2022 AfLS, AfPS Conference

14 Nov 2022, 08:00 → 18 Nov 2022, 23:30 Africa/Johannesburg

Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

The time zone is controlled by you as an Indico Setting (top right). The session times will therefore be shifted if you are not set to Central Africa Time (CAT) = GMT+2.

 

To register for our 2023 conference, please go here

 

Welcome to the 2022 joint virtual meeting of the African Light Source (AfLS), the African Physical Society (AfPS), and co-convened with several other Pan African professional science societies, all hosted by  .  We hope that you will join us as we communicate and celebrate Big Science and Big Goals for Africa!

Participating Organisations

As advanced light sources support multiple disciplines, the AfLS conference formally includes participation by the following Pan African scientific societies, which we are proud to count as supporters and partners in our vision to establish an advanced light source on the African continent.

Programme Outline

The meeting program will cover a broad range of topics in four different tracks.

Track 1 : AfLS :	14h00 - 19:00 CAT/GMT+2
Track 2 : AfPS :	09h00 - 17:00 CAT/GMT+2
Track 3 : Co-Convenors :	09h00 - 19:00 CAT/GMT+2

 

 

 

The format of this exciting virtual meeting will allow attendees to take full advantage of the overlap between the different participating organizations. All registrants will be able to attend sessions in any track with a single registration.

Contributed oral presentations and posters are welcome. Please identify the track of your participation at the registration and abstract submission phases. 

Registrants will be sent the Zoom room links shortly before the conference. Each track will have its own Room within the same Zoom Session. All sessions will be lived streamed to YouTube.

The programme details, as they are updated, are available in the Timetable link on the left-hand menu.

Students and Early Career Scientists Welcome

There is a limited amount of financial support for students and early-career professionals for online data packages for the conference.  Applicants must first fully register and then apply using the link in the left panel.

Participation

The Joint Organizing Committee of this meeting observes the basic policy of non-discrimination and affirms the right and freedom of scientists to associate in international scientific activity without regard to factors such as ethnic origin, religion, citizenship, language, political stance, gender, sex or age, in accordance with the Statutes of the International Council for Science.

No barriers, which would prevent the participation of bona fide scientists, will exist at this meeting.

Abstract_template.docx

Monday, 14 November

09:30 → 12:00 Partner: African Physical Society

10:00 Compatibility of Transformer Insulating Paper (Kraft paper) with Nanofluid prepared from Neem Oil Ester

Samson Okikiola Oparanti1, Andrew Adewunmi Adekunle2, Abdulsalam Ismaila Galadima2, Abdelghaffar Amoka Abdelmalik2
1. Université du Québec à Chicoutimi, 555, boulevard de l'Université, Saguenay, Quebec, G7H 2B1
2. Ahmadu Bello University Zaria Samaru Campus, Community Market, 810211, Zaria, Nigeria
Corresponding author e-mail address: samson-okikiola.oparanti1@uqac.ca
1. Introduction
Sustainable, reliable, and environmentally friendly source of energy is currently a major focus of humanity. This is captured among the sustainable development goals. Electrical power generation has been a critical endeavour toward achieving such goal. Among the important pieces of equipment used in power generation is a transformer which uses oil for its cooling and insulation. The commonly used insulating oil is mineral oil but it is not biodegradable. Current investigations show that oil from plants has the potential to completely replace mineral oil when further chemical modification and the addition of an additive to the oil are considered 1. The addition of nanoparticles to plant-based oil shows improvement in both physicochemical and dielectric properties 2 However, little attention was placed on the compatibility of the prepared nanofluid with the paper.

In this work, the compatibility of nanofluid prepared from neem oil methyl ester and kraft insulating paper is considered. The nanofluids were prepared by adding 0.1 wt.% to 0.5 wt.% of nanoparticles in step of 0.1 to the base oil. The addition of SiO2 nanoparticles (18 nm) to the base oil increases the dielectric constant and reduces the dielectric loss of the base fluid. At 30 oC and 60 Hz, the dielectric constant of the base fluid increases from 3.38 to 5.5 when 0.5 wt.% of nanoparticles were added to the base. Also, the dielectric loss of the oil decreases from 0.06 to 0.0023 when 0.5 wt.% nanoparticles were added to the base fluid. The dielectric loss and breakdown voltage of nanofluid-impregnated paper were determined, and the result is similar to the mineral oil-impregnated paper. The average breakdown voltage of mineral oil-impregnated paper is 16 kV and 15 kV for nanofluid-impregnated paper. The result indicated that nanofluid from methyl ester of neem oil has no negative effect on the performance of kraft paper. This nanofluid is a promising alternative to insulating oil in high-voltage equipment since it has good compatibility with solid insulating material.

1. Results
   The graph in Figures 1 and 2 shows the dielectric loss of impregnated kraft paper and the breakdown strength respectively. This result is similar to the one reported by Ref 2.
   
   The sample codes are as follows; DP is dry paper, (MOP) mineral oil and paper, 0.1paper (nanofluid with 0.1wt.% nanoparticle and paper), EFP (methyl ester with paper), NFP (nanofluid with paper).

1 Abdelmalik, A. A. "Chemically modified palm kernel oil ester: A possible sustainable alternative insulating fluid." Sustainable Materials and Technologies 1 (2014): 42-51.
2 S. O. Oparanti, A. A. Khaleed, A. A. Abdelmalik and N. M. Chalashkanov, "Dielectric characterization of palm kernel oil ester-based insulating nanofluid," 2020 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP), 2020, pp. 211-214, doi: 10.1109/CEIDP49254.2020.9437477.

Speaker: Mr SAMSON OKIKIOLA Oparanti (Université du Québec à Chicoutimi, 555, boulevard de l'Université, Saguenay, Quebec, G7H 2B1)

10:30 (2+1)D Graphene in a magnetic field in Non-Commutative Space

In this work, we study the (2+1)D graphene in a magnetic field in non-commutative space. We solve the system in a direct method in order to obtain the energy eigenvalues and the corresponding wave function of the system.To conclude in the end that the studied system has been affected by the deformation of the space.

Speaker: Mr LAKHDAR SEK (University of Biskra-Algeria)

Graphene in noncommutative space.docx

11:00 Simulation of X-ray tubes using Geant4 Monte Carlo toolkit

This paper is linked to the research and development in the field of Monte Carlo simulation and its application in the simulation of X-ray sources. In this work, the Geant4 toolkit was used to simulate X-ray spectra produced by the interaction of an electron beam with a dense target of Tungsten in an X-ray tube. Additionally, We simulated the Half-Value Layer (HVL) and spatial distribution of x-rays (anode heel effect). Finally, the obtained results were compared and validated against existing data in the literature. This comparison shows a good agreement between Geant4 results and other data.

Speaker: Abdelghani Idrissi (ERSN, FS, Abdelmalek Essaadi University, Tetouan, Morocco.)

11:30 Ferrimagnetic mixed Ising spin (7/2, 1/2) system: by Mean Field Theory, Exact Recursion Relations and Monte Carlo method

Based on Mean Field Theory, Exact Recursion Relations, and Monte Carlo Simulations, we have studied phase diagrams and magnetic properties of the mixed system of Ising spin-7/2 and spin-1/2 coupled ferrimagnetically. The system consists of two interpenetrating face-centered cubic sublattices of each spin type. A comparative analysis of the obtained results by these methods has been developed. Our calculations have shown a qualitatively good agreement between these three methods' results. However, quantitatively, the produced output quantities values by them show a non-negligible difference. The reasons for that quantitative disagreement have been pointed out in the approximations applied in these different methods. These methods remain nevertheless powerful tools for studying such kinds of systems.

Keywords: Mean Field Theory, Exact Recursion Relations, Monte Carlo Simulations,
magnetic properties, Ising spins, power tools.

Speaker: Dr G. Dimitri NGANTSO (Groupe de Simulations numériques en Magnétisme et Catalyse (GSMC), Faculté des Sciences et Techniques, P.O. Box 69, Université Marien Ngouabi de Brazzaville, Congo.)

14:00 → 14:30 Opening

Convener: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

14:00 Opening

Official Opening

Speaker: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

14:05 AfLS Welcome Address

Speaker: Simon Connell (University of Johannesburg)

AfLS4-2022-Calling Stick.pdf

AfLS4-2022-Calling Stick.pptx

14:10 AfPS Welcome Address

Speaker: Ahmadou Wague (African Physical; Society)

14:15 BIUST Welcome Address

14:30 → 15:00 Plenary

Plenary

Convener: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

14:30 Bio/chemo-inspired electronic oscillators and their use in commanding/modulating optoelectronic and microelectromechanical systems

Bio-inspiration has its way on technology since many years. Its present and future impact impact in medicine, security and defense issues is of special interest. This presentation reports on the design of electronic and microcontroller simulators of biological and chemical oscillators. Then we indicate how those bio/chemo oscillators can be used to monitor and command microelectromechanical systems, semiconductor lasers and optoelectronic oscillators for the generation of special actuation and special optical waves.

Speaker: Prof. Paul Woafo (University of Yaounde I)

15:00 → 16:00 AfLS Contribution: AfLS-Contribution

AfLS Contribution

Convener: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

15:00 How the characterization of cement-based materials by beamline techniques can boost sustainable development in Africa

The African continent is the one with the highest rate of urbanisation and it is expected that the local demand of building materials, such as cement, will drastically increase to support demographic, urban and economic growth. Most African countries are net cement importers and this, combined with the need of cutting CO2 emissions associated with Portland cement production and transport, may stimulate the development of a local cement industry, which may lead the global transition towards sustainability. Indeed, raw materials for the production of alternative cements, such as kaolinitic clays, are abundant across Africa, and a sustainable exploitation of these resources can contribute to both reducing the African dependence on cement import and favouring the creation of new jobs.
The design of sustainable binders, alternative to Portland cement, necessitates a bottom-up, knowledge-based approach, by which the understanding of small-scale chemical processes represents a fundamental step towards the engineering of materials with tailored macroscopic properties.
This contribution illustrates how fundamental knowledge of the processes occurring at the solid-liquid interface in cement systems can be acquired by different beamline techniques, relying on both synchrotron light and neutron sources. Specifically, advanced methods based on XRD-microtomography, near-field ptychographic and holographic nano-tomography, and neutron dark field imaging were implemented to assess the details of microstructural evolution in cement-based materials, and how the kinetics of this process can be modified to control the material’s engineering properties.

Speaker: Prof. Luca Valentini (University of Padua)

valentini.pptx

15:30 XAFS studies at Photon Factory, KEK, and a faculty and student team visit

Photon Factory (PF) is a synchrotron radiation facility in KEK Tsukuba campus. We have two rings, PF and PF-AR (Advanced Ring). PF is operated with the beam energy of 2.5 GeV, and PF-AR 6.5 GeV, which provides higher energy regions. There are ~50 end stations including 6 x-ray absorption fine structure (XAFS) beamlines: 9A, 9C, 12C, 15A1, NW2A and NW10A.

XAFS is one of the most popular methods at synchrotrons and is applied to study a wide variety of fields such as catalysts, batteries, functional oxides, minerals and environmental samples. XAFS is divided into two regions, x-ray absorption near edge structure (XANES) and extended x-ray absorption fine structure (EXAFS). XANES is the region of the spectrum from just below the absorption edge to ~50 eV above the edge. EXAFS is the other higher energy region above XANES and analysed to determine local structures of elements of interest. A couple of XAFS studies performed at PF are shared.

In the latter part of my talk, I would like to share my story on the AfLS project. I have been involved in the AfLS project since 2015. In 2015, the first AfLS conference was held at ESRF. Grenoble, France. Dr. Francesco Sette, Director General of ESRF, gave impressive words in his welcome speech, “Science is Peace”, and I made many friends. In 2017, we welcomed a faculty and student team from the Botswana International University of Science & Technology (BIUST). They stayed for a month and performed XRD experiments. We are happy if another team will visit us to perform synchrotron experiments, in particular, XAFS experiments.

Speaker: Hitoshi Abe (Photon Factory (PF), Institute of Materials Structure Science (IMSS), High Energy Accelerator Research Organization (KEK))

15:00 → 16:00 Partner: Partner - Contribution

15:00 The cosmology of changing 'constants'

This talk presents a brief overview of the cosmological implications of evolving the cosmological and gravitational 'constants' with time. We will show that such considerations might alleviate the so-called cosmological constant and coincidence problems and open potential avenues for the resolution of the dark energy dilemma.

Speaker: Amare Abebe (North-West University)

15:15 Production of a Higgs boson in association with a pair of fermions in the presence of a circularly polarized laser field

In the centre of mass frame, we have investigated the process of Higgs-strahlung production in association with a pair of fermions, $e^{+}e^{-}\rightarrow f\bar{f} H$, at the leading order in the presence of an intense electromagnetic field with circular polarization. Our analytical calculations are based on the Narrow Width Approximation (NWA), which is valid in the leading order as $\Gamma_{Z}/M_{Z}=2\%$. We have considered only the initial particles inside the laser field as a first step. In the second part, we have embedded both initial and final particles in the laser field. We have analyzed the angular distribution of the produced Higgs boson as a function of the laser parameters in both cases. We have found that, the order of magnitude of the differential cross-section of both processes $e^{+}e^{-}\rightarrow\mu^{+}\mu^{-}H$ and $e^{+}e^{-}\rightarrow b\bar{b} H$ is reduced more significantly in the case where both initial and final particles are embedded in the laser field.

Speakers: Moha OUALI (Recherche Laboratory in Physics and Engineering Sciences, Team of Modern and Applied Physics, FPBM, USMS, Morocco) , Moha OUALI (Recherche Laboratory in Physics and Engineering Sciences, Team of Modern and Applied Physics, FPBM, USMS, Morocco.)

15:30 Thermodynamics of Non-linear magnetic-charged AdS black hole surrounded by quintessence, in the background of perfect fluid dark matter

In this work, we study the thermodynamic features of a non-linear magnetic-charged AdS black hole surrounded by quintessence, in the background of perfect fluid dark matter(PFDM). After having constructed the corresponding metric, we put out the mass and the temperature of the black hole, in order to get its entropy. Subsequently, we find the expression of the pressure which leads us to get the table of critical values and the isothermal diagram. Especially, we find that the critical values of the temperature and the pressure increase as the dark matter parameter increases. Also, analysing the isothermal diagram, we observe a van der Waals-like behaviour remarked by the presence of a first-order phase transition when we cross the critical temperature. Additionally, we compute and plot the heat capacity of the black hole and find that a second-order phase transition occurs, leading the black hole to move from stable phase to unstable one. Furthermore, it comes out that this phase transition point is shifted towards higher values of the horizon radius, as we decrease the dark matter density and increase the quintessence density.

Speaker: Ragil Ndongmo (University of Yaoundé 1)

15:45 Induced neutrino charge in a magnetized medium

In standard model of electroweak interaction, neutrino charge in vacuum vanishes and this follows from the requirement of anomaly cancelation $(SU(2)_{L} \times U(1)_{Y})$.
In a thermal medium in presence of an external electro-magnetic field,
neutrino can interact with photon, mediated by the corresponding charged
leptons (real or virtual). Thus it acquires an effective charge. In this theory, this comes from the vector type and axial vector type vertex of
weak interaction. In absence of magnetic field only the vector type vertex contributes [1-2]. On the other hand in a magnetized plasma, the
axial vector part also start contributing to the effective charge
of neutrino. This contribution is dominant to order $\frac{eB}{m_{e}^2}$ for $eB < m_{e}^2$,
when $B$ is the magnetic field. The size of the contribution is: $ e^{\nu_{a}}_{eff} \sim -(3.036 \times 10^{-12})\left[g_{A}e\left(\frac{{ B}}{B_{c}}\right) \frac{1}{\pi^{3/2}}\right] \left(\sqrt{\frac{m_{e}}{T}} \right) e^{-m_{e}/T}\cosh(\mu/T)(1-\lambda)\cos\theta.$
In this equation, for electron neutrinos, $g_{\rm A} = (-1 + 1/2)$ and for mu and tau neutrinos
$g_{\rm A} = (1 - 1/2)$, $B_{c} \sim \frac{m_{e}^{2}}{e}$, $m_{e}$ is the electron mass, $e$ is electron charge, $T$ is temperature, $\mu$ is the chemical potential, $\lambda$ happens to be the helicity of the (Majorana type) neutrino and $\theta$ is the angle between the neutrino momentum and the magnetic field.
In an earlier paper we had obtained this result[3].
In this paper we estimate the contribution
to neutrino effective charge from the vector type (coupling constant $g_{V}$) vertex $e^{\nu_{V}}_{eff}$ coming from the polarization tensor $\Pi_{\mu\nu}$ in a magnetized medium. For electron type neutrinos $g_{\rm V} = 1 - (1 - 4 \sin^2 \theta_{\rm W})/2$,
and for tau and mu type neutrino $g_{\rm V} = -(1 - 4 \sin^2 \theta_{\rm W})/2 $.
We note that keeping PCT symmetry in view, the leading powers of $B$ and $\mu$
that appears in the expression of $e^{\nu_{V}}_{eff}$ is of order $(eB)^{2}$ and $\mu^{2}$. We further elucidate on the direction dependence of this charge thats a manifestation of loss of isotropy due to the presence of an external field. The expression of the induced charge from the vector type vertex happen to be:
\begin{eqnarray}
e^{\nu_{V}}{eff} &=& \frac{G{F}g_{V}}{\sqrt{2}e} \left(\frac{e^{2} m_{e}^{2}}{ 1.68\pi^{\frac{3}{2}}} e^{-\frac{\sqrt{2}m_{e}}{T}}{\cal F}(\theta)\right)
\left(1- \frac{\lambda|k|}{\omega}\right)\left[\left(\frac{T}{m_{e}}\right)^{\frac{1}{2}} + \left(\frac{m_{e}}{T}\right)^{\frac{3}{2}} \left(\frac{eB}{m_{e}^{2}}\right)^{2}\right].
\end{eqnarray}
In the ultra-relativistic limit the neutrinos with $\lambda = -1$ acquire the charge, the other helicity state remains charge neutral. We conclude this work by inferring on astrophysical and cosmological consequences of the same.

[1] J. F. Nieves and P. B. Pal, Phys. Rev. D 49, 1398 (1994), R. N. Mohapatra and P. B. Pal. Massive neutrinos in Physics and Astrophysics, (World Scientific, 2nd Ed. 1998).

[2] V. N. Oraevsky, V. B. Semikoz and Ya. A. Smorodinsky, JETP Lett. 43, 709 (1986).

[3] Avijit K. Ganguly, Venktesh Singh, Damini Singh, Ankur Chaubey, MDPI Galaxies 9,2(2021).

Speaker: Ankur Chaubey

16:00 → 16:15 Tea

Tea

16:15 → 17:15 Plenary

Plenary

Convener: Sekazi Mtingwa (Massachusetts Institute of Technology &amp; Brookhaven National Laboratory&amp; African Laser Centre)

16:15 A Centre of Excellence in Planetary Space Science and Technology in Africa

Planetary and Space Science and Technology (PSST) has been identified as a key area of investment in Africa as it provides graduates and young scientists with both the necessary soft and practical skills to face 21 st Century challenges, such as digital innovation. PSST for Africa means not only blue-sky research and skilled graduates in STEM disciplines but is intricately linked to socio-economic development. Many countries have already seen the benefits arising from PSST technology and industry for agricultural projects (SDG 2-Zero Hunger), earth observation, communication networks, monitoring/prevention of disaster and geohazards (SDG 13-Climate Action), space defence and telemedicine amongst others. It has been demonstrated that developments in PSST help the scientific community to address trans-boundary issues related to developmental and environmental problems, such as water management, and can consolidate international relationships, promote collaborations and optimize the use of limited funds. Research teams in PSST are often at the forefront of the application of cutting edge technologies for the solution of complex scientific problems such as the habitability of extraterrestrial worlds.

PSST is bound to create in Africa highly skilled jobs that are needed for socio-economic development on a continent that is rapidly embracing the 4 th industrial revolution.

Here I will present ongoing pan-African actions aiming at: i) increase the accessibility to STEM in African HE; ii) modernize existing PSST programmes in collaboration with industry and policy makers; iii) foster the internationalization of PSST teams and institutes; iv) promote standardization of PSST in Africa to support the mobility of students.

To achieve these ambitious goals we are working at the creation of a Centre of Excellence in PSST (CESST) which will host a virtual platform to increase accessibility to education and training materials whilst also coordinating collaborative actions.

Moreover, PSST has the potential to inspire young Africans and attract them towards STEM higher education programmes. PSST can excite the imagination of the public and stimulate the interest of young and old alike, especially when combining cutting edge discoveries with traditional knowledge.

Speaker: Prof. Fulvio Franchi (BIUST)

16:45 A Synchrotron as Accelerator of Science Development in Central America and the Caribbean

We want to identify possible ambitious projects that, through a strong regional collaboration, may accelerate the process of filling the scientific gap between Central America and the Caribbean (CAC) and the rest of Latin America.

We analyze the actual mechanisms used in the past for the above purpose, in order to identify the bottlenecks at the origin of the problem, and analyze possible experiences in other regions that have fulfilled analogous results.

The main bottlenecks are the scarcity of public research centers and little or no research in
private universities. This requires that the "Central American Science and Technology Fund" proposed
by the government of Guatemala, and pending of a decision by the Summit of Central American Heads
of State be approved, and focus on objectives capable of attracting the attention of the non-academic
sector, first and foremost policy makers, but also civil society in general. This requires ambitious
projects, and the successful experience of SESAME ("Synchrotron Light for Experimental Science and
Applications in Middle East ") offers an interesting basis for reflection, as it allows scientific research
and short-term practical and social applications. Such an objective may attract the attention of the non-
academic sector, first and foremost policy makers, but also civil society in general. The understanding
of the value of the initiative by these sectors is crucial to create the conditions for the necessary financing
by the governments of the region, possibly in collaboration with the regional and international
development banks. The foreseen outputs will be both of academic and social impact. Beside the direct
use of the synchrotron, one can expect advantages for doctoral training and the prevention of brain
drain. More generally, as David Gross uses to remind: Science drives Technology, Technology drives
Innovation, and this eventually leads to the upgrade of the welfare.

Speaker: Dr Galileo Viollini

17:15 → 17:30 Tea

Tea

17:30 → 19:00 Discussion: Ministers Forum

Open Forum

Convener: Lawrence Norris (African Physical Society )

Tuesday, 15 November

10:00 → 12:00 Partner: African Physical Society

10:00 NCO and OCN adsorption and decomposition study on the Ag(110) surface

The adsorption of C, N, O, CO, CN, NCO and OCN, as well as CO, CN, NCO and OCN decomposition on Ag(110) surface were studied by using the density functional theory (DFT) combined with the periodic slab model. Preferential site of each adsorbate has been determinated : C, N and O (hollow site), CO and CN (top site), NCO (long bridge site) and OCN (short bridge site). Work function and dipole moment changes allowed us to determine the direction of charge transfer. We evaluated diffusion barrier of all adsorbates and analyzed the interaction between the adsorbate and the surface, in the framework of the local density of states. Thermochemical decomposition of CO,CN, NCO and OCN on Ag(110) surface has been found energetically unfavorable. The CI-NEB calculations of decomposition of CO, CN, NCO and OCN on Ag(110) also shown that, the decomposition reactions CO, CN, NCO and OCN on Ag(110) are endothermics.

Speaker: Cedric Clarfeler Boungou

10:30 Edge detection of lithological structures Using Analytical Signal Technique on gravity data; a case of Gombe arm of Benue Trough

The study was carried out to map out litho-structures in the Gombe arm of Benue trough by interpreting gravity data of the study area using the Analytical signal method. The bouguer and analytic maps were drawn and represented in the work to show the distribution of the anomalies in the study area. The method displays the gravity anomalies of an area through the amplitudes of the directional analytic signals. The study area showed high anomalies in the northeastern part and southern part of the study area i.e. Dukku and Akko, which was attributed to the presence of metamorphic rocks which caused positive anomalies and sedimentary rocks in the areas which caused the negative anomalies.

Key words: Edge detection, Lithological structure, gravity data, Analytical signal.

Speakers: Michael Ohakwere-Eze, Mr Alhassan Ahmad (Federal University of Kashere)

11:00 Shape evolution of even-A {112-124}^Sn isotopes within RHB

The evolution of even–A {112-124}^Sn isotopes is investigated using the relativistic Hartree-Bogoliubov Theory within the explicit Density Dependent Meson-Exchange (DD-ME2) and Density-Dependent Point-Coupling (DD-PC1) models. The binding energies are compared to the predictions of finite range droplet model (FRDM) and to the available experimental data. A reasonable and satisfactory agreement between the theoretical models and experiment is established.

Speaker: Mohamed El Adri (Cadi Ayyad University, FSSM)

11:30 Topological phases of Su-Schrieffer-Heeger alternating ladders

Alternating ladders constructed from unit cells consisting of two rungs with odd number of sites (one or three sites) connected to two rungs with even number of sites (two sites) are investigated using the Su-Schrieffer-Heeger (SSH) model. Rich phase diagrams of topological insulating phases separated by critical lines are identified and compared to phases of regular two and three leg SSH ladders. The topological nature of these phase diagrams depend on the choices between the equivalent unit cells that construct the alternating ladders.

Speaker: Dr Anas Abdelwahab (Leibniz University Hannover)

14:00 → 15:30 Plenary

Plenary

Convener: Lawrence Norris (National Society of Black Physicists)

14:00 The European XFEL Facility

The European X-Ray Free-Electron Laser Facility (European XFEL) is an X-ray research laser facility commissioned during 2017. The first laser pulses were produced in May 2017[2][3] and the facility started user operation in September 2017.[4] The international project with twelve participating countries; nine shareholders at the time of commissioning (Denmark, France, Germany, Hungary, Poland, Russia, Slovakia, Sweden and Switzerland), later joined by three other partners (Italy, Spain and the United Kingdom),[5][6] is located in the German federal states of Hamburg and Schleswig-Holstein.[7] A free-electron laser generates high-intensity electromagnetic radiation by accelerating electrons to relativistic speeds and directing them through special magnetic structures. The European XFEL is constructed such that the electrons produce X-ray light in synchronisation, resulting in high-intensity X-ray pulses with the properties of laser light and at intensities much brighter than those produced by conventional synchrotron light sources.

The 3.4 km long European XFEL generates extremely intense X-ray flashes used by researchers from all over the world. The flashes are produced in underground tunnels and allow scientists to map atomic details of viruses, film chemical reactions, and study processes in the interior of planets.

Speaker: Dr Robert Fiedenhasl (European XFEL)

14:30 The Compact XFEL Project

Arizona State University (ASU) is pursuing a concept for
a compact x-ray FEL (CXFEL) that uses nanopatterning
of the electron beam via electron diffraction and emittance
exchange to enable fully coherent x-ray output from electron
beams with an energy of a few tens of MeV. This low energy
is enabled by nanobunching and use of a short pulse laser
field as an undulator, resulting in an XFEL with 10 m total
length and modest cost. The method of electron bunching is
deterministic and flexible, rather than dependent on SASE
amplification, so that the x-ray output is coherent in time and
frequency. The phase of the x-ray pulse can be controlled
and manipulated so that new opportunities for ultrafast x-ray
science are enabled using attosecond pulses, very narrow line
widths, or extremely precise timing among multiple pulses
with different colors. These properties may be transferred
to large XFELs through seeding with the CXFEL beam.
Construction of the CXFEL accelerator and laboratory are
underway, along with initial experiments to demonstrate
nanopatterning via electron diffraction. An overview of the
methods and project are presented.

Speaker: Prof. William Graves (Arizona State University)

15:00 A report on the LAAAMP FA-ST team visit to the ESRF

Speaker: Gideon Chinamatira (University of the Witwatersrand)

15:30 → 15:45 Tea

Tea

15:45 → 17:15 Plenary

Plenary

Convener: Marcus Newton (University of Southampton)

15:45 Serial Femto Second Crystallography

Serial femtosecond crystallography (SFX) usually involves a liquid jet of many (approximately 108) small crystals injected into the interaction point of an X-ray free-electron laser (XFEL). The high-flux, femtosecond pulses available at XFELs enable a ‘diffract before destruction’ approach, yielding Bragg reflections in single-shot frames from individual submicrometre crystals. The femtosecond duration of data collection eliminates the role of beam damage26. The data collection occurs at room temperature using a liquid jet of suspended crystals, preserving the integrity of samples that may be sensitive to freezing or desolvation. Sample preparation involves loading a sample suspended in solvent into a pump syringe that is attached to a jet delivery system.

Speaker: Prof. Henry Chapman (DESY)

16:15 Ultra fast atomic pair distribution function (PDF) analysis: a new chapter in the goal of atomic movies

Abstract: It has long been a goal to obtain "atomic movies", where frames are captured showing how atoms rearrange during after excitation. To do this, we need a camera that can "see" atoms, with a shutter speed and a frame-rate on the femtosecond time-scales, the time-scale of atomic motions. It has long been realized that diffraction is a way to see atoms, and XFELs allow us to do diffraction in a stroboscopic mode on femtosecond timescales. If you have a well defined crystal, you can use crystallographic methods to solve with high quantitative accuracy the average position of atoms in the crystal, and from the early dates of ultra fast x-ray studies there have been crysatllographic measurements that sought to follow atomic trajectories. However, if your target material is not a crystal but a molecule or a cluster of atoms or a nanoparticle, crystallography is no longer a good starting point for analyzing your diffraction data. The atomic pair distribution function (PDF) analysis of powder or single-crystal diffraction data is now highly developed for this purpose and has become widlely used in the chemical and materials science communities. The PDF function directly measures the relative positions of atoms in real-space and so, in principle, is a great option for making molecular movies. The measurements require wide ranges of diffraction/reciprocal space to measured with good precision using short-wavelength probe particles. All of these aspects present challenges for first generation XFELs. However, currently emerging are XFELs that can provide good flux of hard x-rays (~30 keV energy for example) making in principle ufPDF a very real possibility. The short wavelength of electrons also suggests that ultrafast electron diffraction could be a explored for PDF analysis too. In this talk I will describe the PDF method and our intital attempts to measure and make corrections to data from LCLS to obtain quantitatively reliable PDFs on picosecond timescales. The experiment is to study the response of electronic dimers (a form of charge density wave) in a strongly correlated electron system, CuIr2S4. Initial results are very promising, suggesting that ufPDF could emerge as a highly promising, fully quantitative method for studying small clusters and molecules, opening the door to molecular movies of non-crystals

Speaker: Simon Billinge (Columbia University)

16:45 In vivo crystallization of protein targets for African Sleeping Sickness (Trypanosoma brucei) Therapeutics

Spontaneous protein crystallization within living cells has been observed several times in nature, e.g. for storage proteins in seeds. In vivo crystal growth can also occur during gene over-expression, as particularly discovered in baculovirus-infected insect cells [1]. We have recently shown that these in vivo crystals represent valuable targets for structural biology after isolation from the cell. Applying serial crystallography techniques at an X-ray free-electron laser (XFEL) as well as using a highly brilliant synchrotron source, single crystal diffraction pattern were collected and combined to yield high-resolution structural information of the associated fully glycosylated protein

Speaker: Prof. Lars Redeke (Universität zu Lübeck Institut für Biochemie)

17:15 → 17:30 Tea

Tea

17:30 → 19:00 AfLS Contribution: IMA

AfLS Contribution

Convener: Michele Zema (International Union of Crystallography)

17:30 Application of Synchrotron Radiation to High Pressure Mineral Physics of Earth’s Core

Synchrotron Radiation is a useful tool to clarify the Earth’s deep interior. Here I would like to present the applications of synchrotron radiation to high pressure mineral physics. We apply this intense X-ray to study the properties and phase and melting relations of the Earth’s materials which can be applied to the Earth’s deep interior. We use various techniques such as X-ray diffraction and spectroscopy. Here I show examples of the use of the synchrotron radiation such as inelastic X-ray scattering at high pressure to determine the sound velocity of the iron alloys, candidate materials of the Earth’s inner core, and X-ray diffraction study at high pressure and temperature to clarify the phase and melting relations of iron-alloys of the Earth’s core. We conducted the sound velocity measurements of hcp-iron and hcp and B2 (bcc) Fe-Ni-Si alloys by using the inelastic x-ray scattering at high pressure. We achieved the sound velocity measurements to the pressure of the Earth’s inner core exceeding 300 GPa. We also studied of the phase relations of the Fe-Ni-Si system to the core pressures, indicating the coexistence of hcp and B2 (bcc) phases at high temperature near the melting point suggesting a possible coexistence of a two-phase mixture in the Earth’s inner core. CPM (Commission of Physics of Minerals) of IMA is encouraging the use of synchrotron radiation. These studies are such examples and clearly show that the synchrotron radiation is a powerful tool for the study of the center of the Earth.
References:
Ikuta et al. (2021). Two-phase mixture of iron–nickel–silicon alloys in the Earth’s inner core, Communications Earth and Environment, https://doi.org/10.1038/s43247-021-00298-1
Dominijanni et al. (2021). Sound Velocity Measurements of B2-Fe-Ni-Si Alloy Under High Pressure by Inelastic X-Ray Scattering: Implications for the Composition of Earth's Core. Geophysical Research Letters, 49, e2021GL096405. https://doi.org/10.1029/2021GL096405

Speaker: Eiji Ohtani (Tohoku University)

18:00 The effect of water on the elasticity of minerals

Hydrous minerals play an important role in the transport of water from the Earth’s surface deep into the Earth’s mantle. At the same time, water incorporated into the minerals, mainly as OH hydroxyl group, influences their physical properties giving rise to possible seismic anomalies. In the present study, two different minerals, namely stishovite, SiO2, with 5mol% of AlOOH substitution, and Al-phase D, (Al,Fe3+)2SiO6H2, have been studied at high pressure by means of single-crystal X-ray diffraction in a diamond anvil cell using synchrotron radiation at the Extreme Conditions Beamline P02.2 of PETRA III (DESY, Hamburg, Germany).

Stishovite, a rutile-structured polymorph of SiO2, is a main component of subducted basaltic lithologies in the lower mantle. At mid lower-mantle depths, a second-order ferroelastic transition to orthorhombic CaCl2-type (post-stishovite) structure occurs, causing extensive elastic shear softening. Previous studies showed that Al incorporation can decrease the transition pressure, while it is still debated whether H substitution has a similar effect. Here we show that the AlOOH substitution not only reduce the transition pressure of the tetragonal to orthorhombic transition, but also has a major influence on the mechanism of the transition, likely because of the occurrence of symmetric hydrogen bonds at high-pressure. By modelling the individual effect of Al and H on the pressure-temperature conditions at which elastic softening of silica phases is expected, we suggest that this softening may be related to some seismic anomalies observed in the topmost part of Earth’s lower mantle, in the proximity of subducted oceanic plates.

Al-phase D, the (Al,Fe3+)2SiO6H2 member of the dense hydrous magnesium silicate (DHMS) phase D, may survive along hot subduction geotherms or even at ambient mantle temperatures in the Earth’s transition zone and lower mantle, playing therefore a major role as water reservoir and carrier in the Earth’s interior. The evolution of the unit-cell volume of Fe-bearing Al-phase D between room pressure and 38 GPa, determined by means of synchrotron X-ray diffraction in a diamond anvil cell, is well described by a 3rd-order Birch-Murnaghan equation of state. Above 38 GPa, a change in the compression behavior is observed, likely related to the high-to-low spin crossover of octahedrally coordinated Fe3+. Contrary to what observed for A,H-bearing stishovite, the strength of H-bonds and likely their symmetrisation do not greatly affect the elastic properties of phase D solid solutions, independently of their compositions, however change in volumes may be associated with spin crossover transitions for Fe-rich compositions.

Speakers: Tiziana Boffa Ballaran (University of bayreuth) , Tiziana Boffa Ballaran (University of Bayreuth)

18:15 How the synchrotron light can prove planetological knowledge: the case of icy planetary bodies

Finding signs of ancient and present life, in the solar system and beyond, is and has been one of the most intriguing challenges in scientific research. Water is one of the essential components for life and interest in 'ocean worlds', such as Jupiter's Europa or Saturn's Enceladus, is particularly vibrant. The recent decision by ESA and NASA to push ahead with plans for a new mission to Europa offers strong incentives to learn more about the surface composition through analysis of current spacecraft data.
Recent satellite inferences about the non-ice component of the world's oceanic crust imply the presence of Na sulphates, other salt hydrates and trapped gases, which could imply that, for example, Europa's ocean should probably contain sulphates, Mg, Na and Cl as major solutes and promising candidate minerals for deep icy mantle rock formation.
Knowledge of the behaviour of sulphate hydrates at pressures and temperatures similar to those of planetary bodies is particularly important to answer questions such as the thickness of the ice shell, its rheology and the radial density of these bodies. In addition, relevant information could be obtained on the potential for geological activity and material exchange between the different layers.

Today, the diamond anvil cell with integrated cryostats and heaters can sample most of the P-T range expected for the interior of the Earth and other planetary bodies. The high brightness and high collimation of the synchrotron radiation (SR) allow X-ray beams to be focused down to micrometre-sized spots to probe minute samples under extreme conditions.
This makes it possible to precisely study the mineral physics of planetary materials.

Results of recent studies using synchrotron data to analyse the behaviour and stability of sulphate mineral groups, particularly phase transitions and transformations, as well as dehydration reactions occurring under non-environmental conditions, and implications for planetary models will be presented.

The Commission on Mineral Physics of the International Mineralogical Association (CMP-IMA) encourages the use of synchrotron radiation because, as the case studies presented show, it offers unique potential for studying the interior and dynamics of planetary bodies.

Speaker: paola comodi

18:30 Synchrotron radiation study of a 200 year-old Gaylussite (Na2Ca(CO3)2·5H2O) specimen from Lagunillas-Mérida, Venezuela, and comparison with a specimen from Lake Magadi, Kenya.

1. Introduction

The mineral gaylussite, Na2Ca(CO3)2·5H2O, was first identified from samples obtained in 1823 during an expedition to Colombia and Venezuela by the French chemist Jean-Baptiste Boussingault and the Peruvian mining engineer and chemist Mariano de Rivero [1]. The mineral samples were collected from Laguna de Urao, a salt lake in Lagunillas, Mérida state, Venezuela, from which some minerals had been previously studied by the German naturalist A. von Humboldt and the Venezuelan patriot, naturalist, and diplomat Manuel Palacio Fajardo. The new mineral, the first discovered in Venezuelan territory, was name by Boussingault gaylussite, in honor of the eminent French chemist. The thermal and hydration/dehydration behavior of gaylussite has been the subject of different studies, aimed at understanding the chemical and crystallographic relationship with other naturally occurring carbonates. Besides the fascinating historical context of the discovery of gaylussite, conflicting reports on the formation of the intermediate hydrate pirssonite, Na2Ca(CO3)2·2H2O, the low temperature (orthorhombic) and high temperature (hexagonal) anhydrates nyerereite, Na2Ca(CO3)2, carried out mostly on synthetic samples, sparked our interest in studying natural gaylussite. Preliminary results are reported here.

1. Results

The gaylussite specimen ENSMP 37496 (collected in 1823 by Boussingault) was an irregular cylinder-like grey fragment of 1.5x0.5 mm approximately. A white, powdery material easily disintegrated from the fragment upon handling. It was gently ground in an agate mortar and used to fill a 1.0 mm borosilicate capillary. High resolution X-ray powder diffraction patterns were collected at the ID22 beamline of ESRF. A Search/Match analysis using the PDF-4+ database [2] and a subsequent Rietveld analysis with TOPAS-Academic [3] indicated the presence of aragonite (29.2%), calcite (2.6%) and, surprisingly, sodium acetate trihydrate (67.9%). A small amount of quartz (0.3%) was also identified. These results prompted the examination of an inner section of the specimen which was carefully scrapped to eliminate material deposited on the surface. The analysis of this sample indicated a 46.5% of aragonite, 42.3% of Na(CH3COO)·3H2O, 0.3% of quartz, and 10.9% of gaylussite. It must be noted that calcium acetate efflorescence (as Ca(CH3COO)2·H2O or Ca(CH3COO)2·1/2H2O) has been extensively reported in calcareous museum objects stored for long periods of time [4,5] due to emission of acetic and formic acid from wood (particularly oak) cabinets [6]. However, Na(CH3COO)·3H2O efflorescence has been reported mainly for glass objects. Upon heating at 650 °C, the Mérida sample shows decomposition to the high temperature phase of nyerereite, Na2Ca(CO3)2, which is hexagonal. Upon cooling to ambient temperature, the low temperature orthorhombic form of nyerereite is obtained. For comparison, a study of specimen ENSMP 53763 from Lake Magadi (Kenya) indicated that this sample is almost pure gaylussite. No sodium or calcium acetate efflorescence is observed. The thermal decomposition was followed in situ by registering powder diffraction patterns every 10 °C from 20 to 650 °C. Pirssonite (Na2Ca(CO3)2·2H2O) forms at approximately 120 °C, low-temperature nyerereite forms at 300 °C, and high-temperature nyerereite starts to form at around 430 °C. Above 450 °C only HT-nyerereite is present and, upon cooling, LT-nyerereite forms and remains at ambient temperature.

1. References

[1] J. B. Boussingault. Ann. Chim. Phys. 31 (1826) 270-276.
[2] S. Gates-Rector and T. N. Blanton. Powder Diffr. 34 (2019) 352-360.
[3] A. A. Coelho. TOPAS-Academic version 6. Coelho Software, Brisbane, Australia, 2016.
[4] L. F. G. Byne, J. Conchol., 9 (1899) 172–178.
[5] N. H. Tennent and T. Baird, Stud. Conserv., 30 (1985) 73–85.
[6] L. T. Gibson and C. M. Watt, Corros. Sci., 52 (2010) 172–178

Acknowledgements: We are grateful for the support of LAAAMP through a FAST Team award and to the STREAMLINE Insight Programme at ESRF. We also thank Dr. E. Gaillou and Musée de Minéralogie MINES Paris for providing the gaylussite specimens ENSMP 37496 (Venezuela) and ENSMP 53763 (Kenya) for this study.

Speakers: Analio Dugarte-Dugarte (Laboratorio de Cristalografía-LNDRX, Facultad de Ciencias, Universidad de Los Andes, Mérida, Venezuela) , Andrew Fitch (ESRF) , Catherine Dejoie (ESRF) , Graciela Diaz de Delgado (Universidad de Los Andes) , José Miguel Delgado (Universidad de Los Andes)

17:30 → 19:15 Partner

17:30 Environmental and human health risks assessment of potentially toxic elements content in soils of a prospective phosphate mining area in Hinda district, Republic of Congo

The present study aims to assess environmental pollution and human health hazard due to potentially toxic elements content in the soils of a prospective phosphate mining area in Hinda district. 24 soil samples were collected in a study area. Samples were analyzed using ICP-MS. Results obtained shown mean concentration of potentially toxic elements above the upper continental crust (UCC) and decreased in the following order: Cr > Pb > Zn > Cu > As > Cd > Hg. Environmental and ecological pollution were evaluated by the calculation of contamination factor (CF) and degree of contamination (Cdeg), geo-accumulation factor (Igeo), and pollution load index (PLI). Results obtained shown the whole study area polluted by potentially toxic elements (PLI > 1). However, carcinogenic health risk was evaluated for children and adults. Results found shown cancer risk levels greater than 1 x 10-4 for both children and adults, also indicating that children are more susceptible to carcinogenic health effects due to potentially toxic elements, leading to an alarming contribution of potentially toxic elements to the cancer. Environmental pathways of potentially toxic elements were described, showing different scenarios of contamination through ingestion and dermal contact by children and adults in the study area. Principal component analysis (PCA) was applied to identify and group the potentially toxic elements in different sampling localities. The present paper will serve as a baseline data for environmental scientists around the world regarding environmental, ecological and human health risks due to potentially toxic elements.

Keywords: Potentially toxic elements, soil contamination, risk assessment, human health risk, prospective phosphate mining area, Republic of Congo.

Speaker: Russel Rolphe Caroll MOUBAKOU DIAHOU (Institut National de Recherche en Sciences Exactes et Naturelles (IRSEN))

17:45 Major, minor and trace element concentrations in leaves of Lavandula stoechas collected from Senhaja Srair region (North of morocco) by INAA and ICP-MS.

1. Introduction (section 1) 10 pt Bold
   This study aimed at analyzing the concentrations of macro and trace elements in Lavandula stoechas medicinal plant from Lamaceae family grown in Senhaja Srair region in the Moroccan Central High Rif.
   To estimate and evaluate the concentration of Na, K, Mg, Mn, Cl, Ca , heavy metals and rare earth elements two analytical techniques are used such as k0-standardisation method of neutron activation analysis (K0-INAA) and inductively coupled plasma-mass spectrometry (ICP-MS) at CNESTEN-Morocco.
   For K0-NAA, Irradiations for 5 hours have been carried out using neutrons of the Triga Mark II research reactor and the induced activity was counted using High Purity Germanium (HPGe) detectors.
   For ICP-MS, 0.300 g of sample was digested in acid (HNO3 supra-pure 65%, and of H2O2 supra-pure 30%) at high pressure and temperature by a microwave speedweve.
   The standard reference material (peach leaves NIST 1547) has been used to check the accuracy and precision of the measurement methods. A good agreement between the experimental results and certified values was observed for K0-NAA and ICP-MS both.
2. Results

Results obtained in this study confirmed the presence of more than 20 elements in lavandula stocheas sample. The elements detected were classified into essential elements (Ca, Cl, Co, Cr, Fe, K, Mg, Mn, Na, and Zn), high and low toxicity elements (Al, As, Br, Cs, Sb, V, Hf, Th, Sc), and rare earth elements (La, Ce, Nd, Sm, Eu Tb, Yb).
Ca, Cl, K, Mg, Na, Fe, Mn, and Al are reflected in the high mineral content of the lavandula stocheas sample, while Cr, Co, Cs, and rare earth and other elements are present in lower concentrations. Figure 1 shows the comparison of determined concentration in this study and the result obtained by Embarech & al [1] of each of principal macro elements.

1. References

[1] K. Embarch1, M. El Mzibri1, K. Lalaoui1, M. Bounakhla, A. Gaudry, S. Ayrault, M. Moskura, M. Hmamouchi. Determination Of Trace- And Macro-Elements In Moroccan Medicinal Plants By The Ko- Neutron Activation Analysis Method. Phys. Chem. News .(2009) 45, 09-16.

Speakers: EL Mahjoub CHAKIR (Laboratory of materials physics and subatomic, Faculty of Sciences, Ibn Tofail University, Kenitra,) , Mr Hamid Bounouira (CNESTEN)

18:00 AUTOMOBILE BATTERY MONITORING SYSTEM USING ARDUINO UNO R3 MICROCONTROLLER BOARD

1.Introduction

A battery is an electrochemical device which converts chemical energy in its active materials to electrical energy via electrochemical reactions (Jung et al., 2016). The temperature, current, and voltage of the battery need to be monitored and used to determine the state of charge and state of health of the battery used in the car in real time. The car starter motor usually draws a high current of over 500A, for generating enough torque for the flywheel to run the engine (Gilles, 2012). A battery monitoring system for determining the state of charge and state of health of the battery can be fabricated using an Arduino Uno microcontroller and installed in the car.

1. Results and Discussion

Figure 1: Unistar battery in Isuzu truck Figure 2: Land Rover Varta battery in Pajero

In Figure 1, the Unistar battery’s state of health was very low on many occasions during which it couldn’t crank the engine of the Isuzu truck. Figure 2 represents the data from a new Land Rover Varta battery installed in a 3000cc Pajero in which its state of charge and state of health coincided and remained at 100% throughout the testing period.

1. Conclusion
   When a battery is brand new and has no defects, its state of charge and state of health will be 100% and it will crank the engine successfully within 0.3 seconds. As the battery ages, deterioration of the active materials takes place and causes it to lose its capacity thereby leading to its failure. The resistance of the battery also keeps increasing with its usage, consequently lowering the current density in the battery. The degradation of the battery usually takes place in the background and may not be easily detected by visual inspection. Installing a BMS into the car can provide a more detailed analysis of the status of the battery and thus save the motorist time and money.

2. References
   [1] Gilles, T. (2012). Automotive Service: Inspection, Maintenance, Repair. Cengage Learning, MA 02451 USA, 8,367.
   [2] Jung, J., Lei, Z. and Jiujun, Z. (2016). Lead-Acid Battery Technologies: Fundamentals, Materials, and Applications. CRC Press, Boca Raton Florida USA, 2-3.

Speaker: Mr Ignatius Barasa (University of Nairobi)

18:15 Development of Networks of Low-Cost Air Quality Monitors in African Cities

As Africa develops, more Africans are living in populated areas, where atmospheric pollution reaches high levels and put their lives at risk. Exposure to air pollution can lead to a wide range of diseases, which includes headaches, stroke, lung cancers, chronic obstructive pulmonary disease, dementia, asthma, type 2 diabetes, and respiratory infections. More generally, chronic exposure can affect every organ in the body. Particulate matter, in particular PM2.5, has been recognized as a leading cause of cancer. The World Health Organization announced in 2018, in one of its reports that more than 90% of children in the world breathe polluted air that put their development and health at risk. It also revealed that pregnant women exposed to polluted air, were more likely to give birth prematurely. More recently, PM were found in foetuses. Atmospheric pollution not only impacts health, neurodevelopment and cognitive ability, but has a high economic cost. Around 1% of GDP is being lost by African countries each year due to poor air quality. Data on atmospheric pollution are scarce in Africa due to lack of monitors in almost all African cities, and that’s why Africa does not show up in any air quality map. Governments which have been too slow to react are increasingly aware of the situation but lack information and financial resources to take adequate measures. One of the big obstacles has been the high upfront cost of high-grade monitors. However, low-cost sensors-based monitors are bringing hope owing to their features. They are easy to deploy and maintain, flexible and cheap. In 2022, a consortium made up of four partners: AfriqAir (Rwanda), Alioune Diop University (Senegal), Makerere University (Uganda) and the University of Douala (Cameroun) was awarded a seed grant for a one-year project by the CAMS-Net to install few networks of low-cost sensors in Senegal and Cameroon. The project aims to determine PM concentrations in few African cities, enhance collaboration between partners and organize seminars. Investigation methods will include sites selection and sensors calibration, deployment and monitoring. Here are reported the activities of the first six months of the project. This period was dedicated to surveys on low-cost sensors; design, manufacturing and delivery of monitors and selection of reference monitoring systems.

Speaker: Dr Bertrand TCHANCHE (Université Alioune Diop de Bambey)

18:30 ULTRASONIC BASED RADAR MAPPING SYSTEM USING MATLAB

We present an ultrasonic-based radar mapping system using MATLAB by Sending sound waves generated from a piezoelectric transducer, ultrasonic transmitters measure the time taken for the reflected wave to return to the transducer to determine the distance of the object. As the technology shift toward autonomous driving, there is some concern about the safety of the technology being used, but with the integration of different sensor systems, the safety of these autonomous systems increases. With the use of an Arduino board and MATLAB software and mounting an ultrasonic sensor vertically, on a stand connected to the servo motor. The ultrasonic sensor produces a set of polar coordinated(r,ϕ,φ), with distance r, measured by the ultrasonic sensor of the objects, the angle, ϕ swept by the servo motor, and the height covered by the ultrasonic sensor z thus can be represented by cylindrical coordinates (r,ϕ,z). The polar coordinates plot 2D plots of the environment and a 3D plot for the cylindrical coordinates. 3D displays of the environment have more potential applications as they provide accurate and detailed information about the object in the environment in particular the location. This provides a cheaper and more efficient way of a 3D mapping system using an ultrasonic sensor and is used in various fields like anti-collision warning systems, AI input systems interacting with the environment, and robotics. Different sensor fusion in Autonomous vehicles to create more reliable and accurate detection systems is growing exponentially, therefore, a need for these systems. Ultrasonic sensor mapping is still a low-cost and reliable method even with the increasing innovation of other mapping systems.

Keywords: Ultrasonic technology, 3D plots of the environment, Arduino board, and MATLAB software.

Speaker: Mr Rodgers Mutugi Gichuru (Maasai Mara University)

Wednesday, 16 November

10:00 → 12:00 Partner: African Physical Society

10:00 FABRICATION OF SURFACE-ENHANCED RAMAN SPECTROSCOPY SUBSTRATES USING SILVER NANOPARTICLES PRODUCED BY LASER ABLATION IN LIQUIDS

Surface-enhanced Raman spectroscopy (SERS) is a Raman variant technique that uses the plasmonic characteristics of metallic nanostructures to intensify Raman signals. The most widely utilized metallic nanoparticles are silver, gold, and copper nanoparticles. Silver nanoparticles (AgNPs) are the most sensitive, with distinctive optical, physical, catalytic, and chemical properties. Physical and chemical approaches are among the ways used to make them. Alternatives to well-known chemical processes include laser ablation of solids in liquids. This technique has a relatively simple experimental setup and produces AgNPs of high purity. The generation of SERS Substrates from AgNPs created by laser ablation of silver granules in clean water is the subject of this research. Here, the optimal parameters were identified by determining the laser energy, pulse repetition frequency, and ablation duration effects on the Surface Plasmon Resonance peak of AgNPs solutions that was centered around 404 nm. The generated AgNPs solutions were taken for Raman measurements. The prominent bands were centered around 196, 640, 824, 1060, and 1538 cm-1 which were assigned to O=Ag2/Ag-N, C-S-C, C-H, C–CO_2^-, C-N, and C=O vibration respectively. Then, the chemical stability of colloidal AgNPs produced was investigated and noted to be stable over the first 8 days. Finally, SERS substrates were applied to the blood. It is worth noting that these substrates enhanced the weak Raman signals of blood.

Speaker: Ms Annah Ondieki (University of Nairobi)

10:30 Transition probability and oscillator strength determination in Os4+ by means of semi-empirical HFR+CPOL and ab initio MCDHF-RCI

Saturnin Enzonga Yoca1,2, Exaucé Bokamba Motoumba1, Pascal Quinet2, Patrick Palmeri2

1 Faculty of Sciences and Techniques, Marien Ngouabi University, BP 69, Brazzaville, Congo
2 African and Malagasy Council for Higher Education - CAMES, O1 BP 134 Ouagadougou 01, Burkina Faso
3 Atomic Physics and Astrophysics, University of Mons - UMONS, B-7000 Mons, Belgium
4 IPNAS, Liège University, B-4000 Liège, Belgium

Corresponding author e-mail address: saturnin.enzongayoca@umng.cg

1. Introduction

Fusion is the process that powers stars like our sun, and promises an inherently safe, near-limitless clean electricity source for the long term, using small amounts of fuel that can be sourced worldwide from inexpensive materials. The fusion process brings together atoms of light elements like hydrogen (the optimal reaction implies deuterium and tritium) at high temperatures to form helium and release tremendous energy as heat, which can then be converted into electricity. But realizing this process in earth is a very challenging task.

Osnium (Z=76) is an element which could be a candidate in plasma-facing materials in thermonuclear fusion devices (Tokamaks, ITER) [1]. As a result, its sputtering may generate ionic impurities of all possible charge states in the duterium-tritium plasma that could contribute to radiation losses in these devices. In this context, the radiative properties (transition probabilities, oscillator strengths, …) of these ion have therefore potential important applications in this domain.

Up to now, the spectrum of four times ionized osmium (OS V) has been much less investigated. Azarov et al. [1] have classified the Os V (5d4 + 5d36s) - 5d36p transitions in spectra recorded of Os in the wavelength range 22.5-210 nm on a 3 m normal incidence spectrograph using a triggered spark light source, and then they have established 57 even levels and 86 odd ones. These authors have also given transition probability values (gA) calculated using orthogonal operators.

As an extension of our previous work on Lu IV, Hf V and Ta VI that belong to the isoelectronic sequence of Er I [3], in view of no radiative rate measurements available in the literature, we have adopted two independent theoretical methods, i.e. the semi-empirical Hartree-Fock with relativistic corrections method (HFR), including core-polarization effects (HFR+CPOL) [4,5], and the ab initio multiconfiguration Dirac-Hartree-Fock with subsequent relativistic configuration interaction method (MCDHF-RCI) [6] in order to determine the transitions probabilities of allowed transitions (E1) in Os4+ and estimate their accuracy.

1. Results

The radiative properties (transition probabilities and oscillator strengths) have been computed employing HFR/HFR+CPOL for the 2677 E1 transitions falling in the UV range 46.37-77.85 nm between all the experimental energy levels published by Azarov et al. [3]. MCDHF-RCI calculations are in progress, and our preliminary results will be presented in details during this conference.

1. References

[1] C. Linsmeier et al. Nucl. Fusion 57 (2017) 092007.
[2] V. I. Azarov, A. J. J. Raassen, Y.N . Joshi, P. H. M. Uylings and A. N. Ryabtsev. Phys. Scr. 56 (1997) 325.
[3] E. Bokamba Motoumba, S. Enzonga Yoca, P. Quinet and P. Palmeri. ADNDT. 133-134 (2020) 101340.
[4] R. D. Cowan.. The Theory of Atomic Structure and Spectra (University of California Press-Berkeley, 1981).
[5] P. Quinet et al.P. Palmeri, É. Biémont, M. M. McCurdy, G. Rieger, E. H. Pinnington, J. E. Lawler and M. E. Wickliffe. MNRAS 307 (1999) 934.
[6] C. Froese Fischer, G. Gaigalas, P. Jonsson, J. Bieron and I. P. Grant. Comput. Phys. Commun. 237 (2019) 184

Speaker: Dr Saturnin Enzonga Yoca (Faculty of Sciences and Techniques Marien Ngouabi University)

11:00 Fuel burnup calculations for current LEU fuel and converted HEU fuel for the Nigerian Research Reactor-1 (NIRR-1) using the WIMS-ANL computer code

The fuel depletion analysis of the NIRR-1 core was performed, and the results were consistent with the literature for the HEU core for similar calculations using different methods, indicating that WIMS-ANL AND REBUS-ANL can be considered a reliable tool for estimating the fuel burnup of a potential LEU core. According to the provided actinide inventory, approximately 1% of the initial U^235 loading of the HEU core has been depleted, and the percentage burnup of the HEU core was higher than the LEU core for the same period of reactor operation. As a result, the LEU core will continue in service for a longer period of time before being replaced. The accumulation of fissile 〖Pu〗^239 and 〖Pu〗^241is insufficient to compensate for the loss in reactivity caused by U^235 depletion, and the concentration of 〖Pu〗^239in spent fuel is insufficient to raise concerns about nuclear weapon design and production.

Speaker: Dr DENNIS SOLOMON BALAMI (UNIVERSITY OF ,MAIDUGURI, BORNO STATE NIGERIA)

11:30 Numerical Modeling and Optimization of CaZrS3 chalcogenide Perovskite Solar Cell by Using SCAPS-1D with theoretical efficiency approaching 20%

1. Introduction

Chalcogenide perovskites ABX3 (A=Alkaline earth metals; B=Transition metals; X=S or Se) have recently been studied, but they still need to be rigorously tested under various conditions. Several experimental studies on these materials have been conducted [1] [2]. Zr-based chalcogenide perovskites (AZrS3, where A is an alkaline earth metal such as Ca, Sr, or Ba) have a d-orbital character, whereas the 4d states are less localized than the 3d states, resulting in a high absorption coefficient and a low effective mass of the charge carriers in these compounds [3].

In this study, a device simulation of CaZrS3 material is reported for the first time, which makes this new study interesting, using the one-dimensional solar cell capacitance simulator SCAPS-1D. Therefore, we tried to propose low cost Electron Transport Materials ETMs (TiO2, ZnO, and SnO2). The influence of thickness, doping concentration (NA), and the working temperature on the device performance were studied.

1. Results

As a result, we have found that for CaZrS3 the most preferment structure is found to be: Au/NiOx/CaZrS3 (Absorber)/ZnO/FTO with a maximum PCE of 19.36%, V_OC of 1.79 V, 〖 J〗_SC of 16.13 mA/cm2 and FF of 89.85%.

1. References

[1] Shaili H 2021 Synthesis of the Sn-based CaSnS3 chalcogenide perovskite thin film as a highly stable photoabsorber for optoelectronic applications J. Alloys Compd. 9
[2] Zitouni H, Tahiri N, El Bounagui O and Ez-Zahraouy H 2020 Electronic, optical and transport properties of perovskite BaZrS3 compound doped with Se for photovoltaic applications Chem. Phys. 538 110923
[3] Kumar M, Singh A, Gill D and Bhattacharya S 2021 Optoelectronic Properties of Chalcogenide Perovskites by Many-Body Perturbation Theory J. Phys. Chem. Lett. 12 5301–7

Speaker: Najwa Chawki

14:00 → 15:30 Plenary

Plenary

Convener: Dr Prosper Ngabonziza (Max Planck Institute for Solid State Research)

14:00 African Light Source + CDR Focus

Speaker: Sekazi Mtingwa (Massachusetts Institute of Technology &amp; Brookhaven National Laboratory&amp; African Laser Centre)

14:30 Dark Field X-ray Microscopy: A Synchrotron-based Rock'n Roll Imaging

Speaker: Dr Can Yildirim (ESRF)

15:00 Quantitative and chemical nanoimaging of heterogeneous materials by 3D X-ray ptychography

Speaker: Dr Julio Cesar da Silva (Institute Neel CNRS and ESRF)

15:30 → 15:45 Tea

Tea

15:45 → 16:15 AfLS Contribution

AfLS Contribution

15:45 A versatile and multi-disciplinary electron microscopy facility at the tip of Africa

The Electron Microscope Unit (EMU), provides a central microscopy service to all departments of the University of Cape Town, as well as to other universities, research institutions and private companies. Staff at the Unit are able to advise users on many aspects of electron microscopy, light microscopy and digital imaging and can take on joint research. The Unit offers a versatile, high quality range of instruments and techniques serving the needs of Engineering (Material and Chemical), Biological Science, Physical Science, Geoscience, Agricultural Science, Biotechnology and Medical Sciences.

The Electron Microscope Unit and the African BioImaging Consortium, both based at UCT, have been awarded grants by the Chan Zuckerberg Initiative (CZI) to expand access to and expertise in bioimaging and microscopy throughout Africa.

Speaker: Prof. Robert Knutsen (University of Cape Town)

EMU (UCT) presentation 16 Nov 2022.pptx

16:15 → 17:15 Plenary

Plenary

Convener: Gihan Kamel (SESAME Light Source)

16:15 SESAME - Highlights and Africa

Speaker: Andrea Lausi (SESAME)

16:45 SESAME - SR-based XAFS/XRF techniques and applications

Speaker: Messaoud Harfouche (SESAME)

17:15 → 17:30 Tea

Tea

17:30 → 19:30 Plenary

Plenary

Convener: Gihan Kamel (SESAME Light Source)

17:30 SESAME - IR Beamline: an oasis of multidisciplinary scientific domains

Speaker: Gihan Kamel (SESAME Light Source)

18:00 SESAME - X-ray diffraction research opportunities at SESAME Materials Science beamline

Speaker: Mahmoud Abdellatief (SESAME synchrotron)

18:30 SESAME - HESEB: the first soft x-ray beamline at SESAME and the research opportunities it brought

Speaker: Prof. Mustafa Genisel (SESAME)

19:00 SESAME - Updates from BEATS, the BEAmline for Tomography at SESAME

Speaker: Dr Gianluca Iori (SESAME)

Thursday, 17 November

10:00 → 12:00 Partner: African Physical Society

10:00 Optimized RbGeI3 based perovskite solar cell with efficiency exceeding 29%

Recent achievements based on lead halide (Pb) perovskites have prompted extensive research on low cost photovoltaics to avoid the main challenges in this regard: Stability and toxicity. In this study, the modeling of the lead-free (Pb) perovskite solar cell device was carried out by considering (RbGeI3) as the absorbing layer of the perovskite. The objective of this work, is to study and optimize the electrical characteristics of the solar cell based on RbGeI3 perovskite materials for AM1.5 illumination.
Method/Analysis: The analysis of the architecture of the solar cell is carried out using the Solar Cell Capacitance Simulator (SCAPS). This is a computer software tool well suited for the analysis of homo- and heterojunctions, multijunctions and Schottky barrier photovoltaic devices. This software tool works and simulates based on the Poisson equation and continuity of electrons and holes. For this model, it is used to optimize the different parameters such as the thickness of (FTO,TiO2,RbGeI3,Spiro-ometad,CuSCN), the defect density of the absorbing layer and their doping (NA), the doping concentrations (ND and NA) of the electron transport material (ETM) and the hole transport materials (HTM),
Improvements: With the proposed simulated model, the efficiency of the perovskite solar cell reaches 30%, which is an improvement of 5-6% over previous models, with the optimization of some material parameters. Therefore, this simulation work will provide practical information for the fabrication of perovskite solar cells to reasonably choose the material parameters and achieve high efficiency.

Speaker: Mr Mohamed Alla (Mohammed V University , Rabat, Morocco.)

10:30 Adsorption of Br2 molecule on the Fe/W(110) substrate: Energetics, electronic and magnetic properties

Using spin-polarized density-functional calculations with generalized gradient approximation (GGA) as the exchange-correlation functional, we report the energetics of adsorption, as well as the electronic and magnetic properties of homonuclear bromine molecule deposited on the Fe/W(110) substrate. The Fe/W(110) substrate consist in Fe monolayer on the topmost W(110) layer such that the Fe atoms are bonded on the bridge adsorption sites of the Wð110Þ surface. Our calculations show that when the Br2 molecule is adsorbed in parallel, oblique or vertical orientation with respect to the surface, the molecule dissociates. However, when the Br2 molecular adsorption is perpendicular to the bridge or top sites, non-dissociative adsorption occurs. We also found that the observed Br2 adsorption properties depend on the interaction between the 4p orbitals of adsorbed bromine specie and the Fe-3d orbitals of Fe atoms of the Fe/W(110) substrate. Furthermore, it is shown that when the bromine atoms are attached on its energetically preferred adsorption sites, the magnetic moments of Fe atoms are reduced while magnetic moment is induced on the bromine atoms. These results are consistent with a previous work on the O2 adsorption.

Speaker: Dr Aubin Lauril LOMANGA OKANA (Marien NGOUABI University)

11:00 The atomic and electronic structure stability of 3C-SiC/SiC interface superstructures: A DFT calculation

We report total energy and electronic structure calculation of SiC/Si interface with unequal atom densities due to apparent lattice matching between them. The result shows several distinctive metastable structures depending on which interface systems are involved. We find that, for a particular interfacial system, the energy differences range between 10-52 meV per Å2 for both Si-C and Si-Si interfaces respectively with 3C-SiC facets having dense surface atoms whilst those of Si being sparse. We find that the interface structures are associated with vacant channels and stabilized by the existence of over-coordinated atoms (floating bonds). We also observed atomic undulation near the Si-C interface pinched at Si substrate to stabilize the interface. We reveal that, the coexistence of floating bonds and dangling bonds (under coordinated atoms) with the transfer of electrons from the dangling bonds to the floating bonds are the microscopic mechanism of the interface stabilization. The calculated interface formation energies indicate that Si-Si is more favorable compared with Si-C. The electronic dispersion structure calculation shows either metallic or semiconducting character due to electron transfer from SiC to Si. The stable structure of SiC(111) on Si(110) shows semi-conducting behaviors while that of the 3C-SiC(111) on Si(111) is metallic and that might be due to the relative electronegativity differences between Si and C atoms.

Speaker: Eric Abavare (KNUST)

11:30 Advances in Materials Characterization and Analysis using the Powder Diffraction File

Crystallographic databases play a vital role in materials research, influencing materials development and providing a reference for materials characterization. Material identification using Powder X-ray diffraction (PXRD) method is the most powerful technique in solid state characterization since the landmark 1936 publication of Hanawalt and Rinn [1]. The International Centre for Diffraction Data (ICDD) Powder Diffraction File (PDF®) [2] is a powerful database for materials characterization that has been used extensively by the scientific community. Starting with 1000 entries on printed cards in 1941, the database has grown to contain over 1 million unique material data sets. The Powder Diffraction File has a wealth of information that a materials scientist can take advantage of for materials identification, characterization, computation and design. The Powder Diffraction File in Relational Database (RDB) format contains extensive chemical, physical, bibliographic and crystallographic data including atomic coordinates enabling characterization and computational analysis.
Proper database structure, data validations and phase-type classifications are crucial in making any database useful and reliable. Various structural and chemical classifications implemented in the database will be presented in detail. These classifications are important in data mining studies and optimizing diffraction pattern search/match methods. While using a database, it is important to know the quality of the crystal structure, diffraction pattern data and any data field of interest found in the database. With the varying quality of published data in the literature, the PDF database editorial review processes require rigorous data evaluation methods to define data based on its quality.

This presentation will focus on exploring recent developments and applications of Powder Diffraction File in various aspects of materials characterization and analysis.

Reference

[1] J.D. Hanawalt and H.W. Rinn Ind. Eng. Chem. Anal. Ed. 8(4) (1936) 244–247.

[2] S. Gates-Rector and T. Blanton. Powd. Diffr. 34(4) (2019) 352-360.

Speaker: Dr Soorya Kabekkodu (ICDD)

14:00 → 15:00 Plenary

Plenary

Convener: Dr Kudakwashe Jakata (European Synchrotron)

14:00 Lightsources for Africa, the Americas, Asia, Middle East and Pacific (LAAAMP)

Speaker: Prof. Michele Zema (International Union of Crystallography)

14:30 The current impact and the bright future of X-ray imaging for palaeontology and evolutionary biology

Speaker: Dr Kathleen Dollman (ESRF)

15:00 → 16:00 AfLS Contribution

AfLS Contribution

Convener: Kudakwashe Jakata (European Synchrotron)

15:00 How synchrotron scanning changed the evolutionary history of sense organs in mammals and their ancestors

It has long been assumed that mammalian ancestors, the "mammal-like reptiles", had primitive sense organs and nervous system, i.e. they had a small brain, simple behaviour, and unrefined sense of smell, sight, touch, hearing and olfaction. In the last 10 years,however,systematic synchrotron and CT scanning of dozens of these "mammal-like reptile" fossil skulls have unraveled a great neurological diversity. We found evidence that whiskers and enhanced olfaction, hearing, and vision likely evolved before the origin of mammals. Neurological and fossil evidence indicate that complex behaviour such as parental care and gregariousness were also commonplace in "mammal-like reptiles". Finally, the brain itself was no smaller in "mammal-like reptiles" than in early mammals.
As dinosaurs and other Mesozoic reptiles were becoming the dominant species in terrestrial ecosystems, "mammal-like reptiles" adapted to a nocturnal way of life, which resulted in a sensory revolution. Enhanced olfaction, audition, and touch compensated for the loss of vision, which altered sensory input to the brain. The whole nervous system thus began evolving towards "mammalness" millions of years before the first mammal appeared.

Speaker: Julien Benoit (Evolutionary Studies Institute, WITS, Johannesburg)

15:30 Elettra SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline

The SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline has been designed by Elettra - Sincrotrone Trieste, in collaboration with the University of Trieste and the INFN, for research in medical diagnostic radiology, material science and life science applications. The use of monochromatic and laminar-shaped beams allows, in principle, an improvement of the clinical quality of images and a reduction of adsorbed dose (because of both monochromaticity and scatter reduction). Moreover, the spatial coherence of the SYRMEP source is used to overcome the poor absorption contrast of many biological samples, by the use of phase-contrast techniques.

A large number of different microimaging and microtomography experiments can be performed in different fields of material science (including geology, volcanology, cultural heritage, palaeontology and agrifood technology) and life science.

Speaker: Dr Franco Zanini (Elettra)

16:00 → 16:15 Tea

Tea

16:15 → 17:15 AfLS Contribution

AfLS Contribution

Convener: Marielle AGBAHOUNGBATA (Semi City)

16:15 Study of multicomponent materials at the BAMline, a multipurpose synchrotron beamline

The BAMline is the multipurpose beamline based at the BESSY II synchrotron facility in Berlin [1]. The beamline covers a broad range of energies from 4 up to 110 keV. Several techniques are available including X-ray absorption and fluorescence spectroscopy as well as computed tomography with various spatial resolution dawn to several m-sized beam. In the current talk we summarize our experience with a combining of several analytical techniques to characterize multicomponent materials. Recent highlights from our beamline include studies of local structure in high-entropy alloys [2], quick homogeneous chemical reactions in water solution [3], as well as the formation of nanoparticles from organic medium [4] using X-ray absorption spectroscopy.

References

[1] H. Riesemeier et al. X-Ray Spectrom. 34 (2005) 160;
[2] I. Martins et al. Chemistry – A European Journal (2022) e202200079;
[3] A. Smekhova et al. Nano Research (2022) https://doi.org/10.1007/s12274-022-5135-3; A. Smekhova et al. J. Alloys Comp. (2022) https://doi.org/10.1016/j.jallcom.2022.165999; A Smekhova et al. Nano Research (2021) https://doi.org/10.1007/s12274-021-3704-5;
[4] K.V. Yusenko et al. ChemNanoMat (2021) https://doi.org/10.1002/cnma.202100281.

Speaker: Kirill Yusenko (Federal Institute for Materials Research and Testing (BAM))

16:45 Tribological and Synchrotron Characterization of sputtered WC-Co thin films

Mild steel offers versatile properties at lower costs. However, due to the severity and complexity of service conditions, several industries are now focusing on structural modification techniques like physical vapor deposition to enhance material performance. Due to the remarkable mechanical characteristics of the material and its potential for use in challenging engineering applications, such as wear resistance, heavy cutting, and excavation sectors, the synthesis of WC-Co thin films by physical vapor deposition technology has garnered significant scientific interest. Control and manipulation of synthesis parameters are of significant concern in order to tailor such material properties and performance. The focus of this work is to, therefore, investigate the effect of Rf magnetron power and deposition temperature on the structure and sliding wear behavior of WC-Co thin film. X-ray photoelectron spectroscopy (XPS) and Grazing Incidence x-ray absorption spectroscopy (GI-XAS) were employed to study the morphology and nature of the thin film. The film-substrate system's wear performance was finally identified and reported.

Speaker: Resego Phiri (BIUST)

17:15 → 17:30 Tea

Tea

17:30 → 18:30 Plenary

Plenary

Convener: Marielle AGBAHOUNGBATA (Semi City)

17:30 XTech Lab - Science and Progress

Speaker: Thierry d'Almeida (CEA)

18:00 NSLS-II Highlights and Africa

Speaker: Qun Shen (Brookhaven National Laboratory)

18:30 → 19:00 AfLS Contribution

AfLS Contribution

Convener: Marielle AGBAHOUNGBATA (Semi City)

18:30 Biomedical Research and Biosciences at NSLS-II

Speaker: Prof. Sean McSweeney (BNL)

18:45 Catalysis and Chemical Sciences at NSLS-II

Speaker: Prof. Ira Waluyo (BNL)

Friday, 18 November

10:00 → 12:00 Partner: African Physical Society

10:00 Identification of waste plastics Using Fourier Transform Infrared Spectroscopy

In this work we present a technique of sorting out waste plastics using FTIR spectroscopy. The IR spectroscopy involves irradiating a sample with light then measurement of absorbance or transmittance is done. This absorption occurs as a result of the vibration and rotation of molecules. Each sample has a unique spectrum, and an analysis of the IR spectra is able to provide the identity of the sample. The past centuries have seen an exponential rise in the production and demand for plastics. Similarly, inappropriate plastic disposal and fragmentation of plastic materials has resulted to an increase in plastic particles and fibers. In order to combat plastic pollution, the issue of plastic recycling has gained importance in recent days. Most plastics are collected without any applied criteria and dumping of these plastics results in the loss of materials that can be reused and leaching of additives which later result to water pollution. Recycling is important as it plays a critical role in the sustainable use of resources. It can also generate revenue if it is turned into a profitable industry. The major key to profitability relies in a technique of identification and classification of plastics that can be efficient and reliable. For economic motivation in the recycling sector then there has to be a balance between capacity, fractional purity and recovery. The first criteria in the process of recycling is sorting and classification of the plastics. Methods that are based on optics have proved efficient in the characterization of plastics and thus pose a greater potential for in situ measurements. This study proved that FTIR can be used in the identification of various plastics and thus fulfil the criteria mentioned above. The method is fast, simple and the results can be reproduced.
Key words: Spectroscopy, FTIR, Absorbance, Spectra and Wavelength

Speaker: Brian Osoro (Maasai Mara University)

2022 African Light Source Conference

10:30 Development of Smartphone-based malaria detection system

To combat malaria, we have developed a diagnostic system using smartphone. Our approach for detecting malaria is based on a smartphone with a 32MP front-facing camera, a 100x phone camera lens, and a custom-written application that makes use of Python's powerful image libraries. The enhanced characteristics of smartphones, such as high-resolution cameras, have made it simple to design a cost-effective malaria detection system. Moreover, a sizable population is already familiar with them and able to buy smartphones. Malaria control in low-resource settings has been difficult because of the high price of malaria-detecting tools. Tools that may be utilized to prevent or reduce Malaria's prevalence are urgently needed. In order to successfully battle Malaria in these far-flung locations and third-world countries, especially in Sub-Saharan Africa, where it is most widespread, we need a low-cost, easier, and quicker technique of malaria identification. Images of the blood sample were captured with the help of the Smartphone and its camera lens and then processed by our software. Based on the final picture, samples were labeled as affirmative or negative. Pictures generated from blood samples positive for Malaria showed ring-shaped structures, whereas images generated from blood samples negative for Malaria showed no structures at all.

Speaker: Mr Alphonce Opiyo (Maasai Mara University, Narok)

11:00 Frist-Principles Study of Magnetic Susceptibility and Field-Dependent Magneto-Optics in Antiferromagnetic Materials

1 Introduction

A magnetic field has been popularly exploited in experiments to manipulate the magnetic properties of materials. The material's response under the external magnetic field can be quantified by magnetic susceptibility. In the computational approach, the magnetic susceptibility is evaluated in the limit of atomistic spin dynamics level, preventing studies on field-dependent quantum mechanical properties [1]. Therefore, the demand for the prediction of magnetic susceptibility and field-dependent phenomena from first-principles methods increases.

2 Methodology [2]

In a new approach, we use the tilting behavior of magnetic moments under the external field. The total energy change with moment-tilted states in density functional theory calculations naturally includes complex spin-spin interactions, such as exchange interactions. By adding the Zeeman energy term, we can find the lowest total energy state under a certain magnetic field, allowing us to extract corresponding net magnetization. At last, magnetic susceptibility can be evaluated by a magnetic field and extracted net magnetization. Materials with two magnetic sites require two tilting angle dimensions to evaluate the lowest total energy state under the field.

3 Results [2]

Fig. 1 shows the comparison between calculated and measured magnetic susceptibility of antiferromagnetic materials, showing reasonably good agreement. We found that the calculated magnetic susceptibility of M2As (M = Cr, Mn, Fe) and Mn3Sn present some discrepancy, which turned out that the measured results don’t follow the typical temperature-dependent behavior of magnetic susceptibility in antiferromagnets. This might be caused by off-stoichiometry or paramagnetic defects. One of the benefits of the new approach is the possibility of field-dependent property calculations. Fig. 2 displays the generation of the polar magneto-optical Kerr effect caused by the external magnetic field. The magneto-optical signal increases with the strength of the magnetic field. Therefore, it demonstrates that a new approach might be used to investigate various field-dependent properties.

4 References

[1] O. Erikssson, A. Bergman, L. Bergqvist, J. Hellsvik. Atomistic spin Dynamics (Oxford University Press, 2017)
[2] K. Kang, K. Yang, K. Puthalath, D. G. Cahill, A. Schleife Phys. Rev. B 105, 184404 (2022)

Speaker: Kisung Kang (Fritz-Haber-Institut der Max-Planck-Gesellschaft)

11:30 Salt Tolerance in Glaberrima rice: Mechanism and approach using micro-proton induced x- ray emission techniques

Salt tolerance is an important constrain for Africa rice. Soil salinity is one of the major
constraints affecting rice production worldwide, especially in the northern part of
Senegal. Susceptibility or tolerance of rice plants to high salinity is a coordinated action
of multiple stress responsive genes, which also interacts with other components of
stress signal transduction pathways. Salt tolerant varieties can be produced by using
two different sets of germplasm. One comprised of a diversity panel of 317 accessions
of O. Glaberrima received from Africa Rice Genetic Resources Unit and checks: FL478
(salt tolerance), IR 29 (salt sensitive), Sahel 210 and Sahel 134. The second is comprised
of an indica diversity panel of 330 genotypes received from IRRI. Both sets were
evaluated under control conditions where they were grown under irrigated lowland
conditions using non-saline river water (EC <1 dSm-1) and also under saline conditions
in a concrete-lined field where salinity was maintained at 4 dSm-1. In this review, we
have updated on mechanisms and genes which can help in transferring of the salt
tolerance into high-yielding rice varieties. We have focused on the need for integrating
plant biology into transgenic and breeding approaches to develop high-yielding as
well as salt tolerant rice varieties. PIXE studies have been performed for determination
of different elements in rice plants. The micro beam analytical technique existent at the
iThemba LABS was applied for the 2D image mapping of fresh rice tissues. The
technique will be used to measure the concentration of low atomic mass elements
based on the targeted it in the rice plants with detection limits of typically 1-10μg/g.

Speaker: Alassane TRAORE (Universite Cheikh Anta Diop Dakar)

13:00 → 15:00 Plenary

Plenary

Convener: Gihan Kamel (SESAME Light Source)

13:00 Current status and future plans of BL04B1/SPring-8

BL04B1 is a bending magnet beamline, where energy-dispersive X-ray diffraction measurements and X-ray radiography observations using white X-rays are available. The X-rays emitted from the bending magnet are directly introduced into the experimental hutch, and white X-rays with a wide energy range up to 145 keV are utilized in measurements. The beamline is also equipped with a compact Si(111) double-crystal monochromator, which makes it possible to perform angle-dispersive X-ray diffraction measurements and X-ray radiographic observations using monochromatic X-rays with the photon energy between 30 and 60 keV. These high-energy X-rays allow us to conduct X-ray observations for samples surrounded totally by materials such as high-pressure vessels.
The beamline has two experimental hutches in tandem, and a large-volume press with a maximum load of 1500 tons is installed in each hutch. These large-volume presses make it possible to carry out high-pressure and high-temperature experiments. The “SPEED-1500” Kawai-type high-pressure press (DIA-type press, upstream hutch) and the “SPEED-Mk. II” Kawai-type high-pressure press (D-DIA–type press, downstream hutch) are installed. The “SPEED-Mk.II” has differential rams (D-RAM) inside, which move independently of the main ram, and we can conduct deformation experiments under high-pressure and high-temperature conditions. By utilizing the large-volume presses with high-energy X-rays, one can routinely carry out in situ observations of materials under high pressure and high temperature conditions up to 100 GPa and 2500 K in the beamline. The technologies including viscosity measurement by in-situ falling sphere viscometry, melt structure measurement by CEASAR system, density measurement by X-ray absorption method, sound velocity measurement et al., are all available in our beamline.

Speaker: Yuji Higo (Japan Synchrotron Radiation Research Institute)

13:30 Synchrotron for Neuroscience – an Asia Pacific Strategic Enterprise” (SYNAPSE)

We plan to comprehensively map the neuron network of an entire human brain at sub-cellular level to reveal the connections. This historical target is made possible by the recent performances of synchrotron x-ray microscopy: 0.3 micrometer resolution at 1 mm3/min image taking speed. However, mapping one human brain would take a very long time and generate a huge amount of data. To overcome problems, SYNAPSE adopts a strategy of simultaneous image acquisition by several synchrotrons and coordinated data management. SYNAPSE will also use other advanced imaging techniques besides synchrotron microscopy: infrared spectromicroscopy, super-resolution visible light 3D microscopy and cryo-electron tomography.

Speaker: Prof. SYNAPSE Consortium (SYNAPSE)

14:00 The beamlines XAFS and XRF at Elettra: scientific highlights and opportunities

Speaker: Dr Giuliana Aquilanti

14:30 Munich Compact Light Source (MuCLS)

For some years now it has been possible to generate high-brilliance X-rays using ring-shaped particle accelerators (synchrotron sources) at large facilities. However, such installations are several hundred meters in diameter and cost billions of euros. As an alternative, the world’s first mini synchrotron – the Munich Compact Light Source (MuCLS) - was installed in 2015 at Technical University of Munich (TUM). It can generate high-brilliance X-rays on a footprint measuring just 5 x 3 meters. The new unit will be used chiefly to research biomedical questions relating to cancer, osteoporosis, pulmonary diseases and arteriosclerosis.

MuCLS creates X-rays through the collision of high-energy electrons with low-energy photons from an infrared laser. Like balls in billiard game, the photons collide with the electrons, absorbing some of their energy and thereby reaching the X-ray range. These collisions can be repeated 65 million times per second as the electrons circulate in a storage ring, and the photons revolve in a resonator. The volume of collisions, and thus the size of the X-ray source, is approximately 45-thousandths of a millimeter: about half the width of a human hair.

In addition to being more compact, the new system has other advantages over conventional X-ray tubes. The X-rays it produces are extremely bright and intense. These brilliant X-rays can distinguish materials better, meaning that are able to detect much smaller tumors in tissue in the future. The MuCLS research activities also include measuring bone properties in osteoporosis and determining altered sizes of pulmonary alveoli in diverse lung diseases. The scientists use the instrument mainly for preclinical research, i.e. examining tissue samples from patients. They also combine the new X-ray source with other systems, such as phase contrast.

The Munich Compact Light Source (MuCLS) is presently operated at the MIBE by the Biomedical Physics group (PI Pfeiffer) as part of the new Center for Advanced Laser Applications (CALA), a joint project between TUM and Ludwig-Maximilians-Universität München (LMU).

Speaker: Dr Martin Dierolf ( Technical University of Munich)

15:00 → 15:15 Tea

Tea

15:15 → 17:45 Plenary

Plenary

Convener: Tshepo Ntsoane (Necsa)

15:15 ESRF-EBS Highlights and Africa

Speaker: Dr Michael Krisch (ESRF)

15:45 LNLS - Highlights and Africa

Speaker: Prof. Harry Westfahl (LNLS)

16:15 Diamond - Highlights and Africa

Speaker: Dr Sam Horrell (Diamond Light Source)

16:45 SESAME Director

Speaker: Khaled Toukan (Chairman of Jordan Atomic Energy Commission)

17:15 AfCA - Science and Progress for Africa

17:45 → 18:00 Tea

Tea

18:00 → 18:30 Closing

Convener: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)

18:00 3 Wise Sages

1. AfCA
2. AfPS
3. AfLS

18:15 BIUST Executive Closing

18:25 Thank you and Closing Ceremony

Speaker: Philip Oluseyi Oladijo (Botswana International University of Science and Technology)