Seminar Series

Speaker: Tim Salditt

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Cytoarchitecture in Brilliant Light

Understanding of biological matter in physiological and pathological states requires quantification of structures, shapes and networks over a wide range of scales. High brilliance synchrotron radiation makes it possible to map large tissue volumes at cellular and sub-cellular resolution [1]. This enables a shift from cell culture to tissues, organisms and organoids. Here we use multi-scale phase-contrast imaging, exploiting coherent wavefield propagation and advanced phase retrieval [2,3].  This enables a new form of fully digital 3D virtual histology [4]. To this end, we discuss optics, phase retrieval, and reconstruction in view of resolution, dose, throughput, and how to find the ‘needle in the haystack’?  How to best exploit the opportunities of 4th generation synchrotron sources. We give examples for applications in three-dimensional virtual histology and patho-histology, offering new insights into the cytoarchitecture of human organs [4-6], from lung and heart to brain, and the respective pathological alterations. And finally we discuss: how to exploit all this data?  

[1] T. Salditt, A. Egner and R. D. Luke (Eds.), Nanoscale Photonic Imaging, Springer Nat, TAP, 134 (2020).  

[2] J. Soltau, M. Vassholz, M. Osterhoff and T. Salditt, “In-line holography with hard x-rays at sub-15 nm resolution”, Optica  8, 818-823 (2021). 

[3] L. M. Lohse, A.-L. Robisch, M. Töpperwien, S. Maretzke, M. Krenkel, J. Hagemann and T. Salditt, A phase-retrieval toolbox for X-ray holography and tomography. J. Synchr. Rad. (2020), 27, 3 

[4] M. Eckermann, B. Schmitzer, F. van der Meer, J. Franz, O. Hansen, C. Stadelmann and T. Salditt, Three-dimensional virtual histology of the human hippocampus based on phase-contrast computed tomography Proc. Natl. Acad. Sci. (2021), 118, 48, e2113835118 

[5] M. Reichardt, P.M. Jensen, V.A. Dahl, A.B. Dahl, M. Ackermann, H. Shah, F. Länger, C. Werlein, M.P. Kuehnel, D. Jonigk and T. Salditt , 3D virtual histopathology of cardiac tissue from Covid-19 patients based on phase-contrast X-ray tomography, eLife (2021), 10:e71359 

[6]J Reichmann et al.,  Human lung virtual histology by multi-scale x-ray phase-contrast computed tomography, Physics in Medicine & Biology 68, 115014 (2023), J. Reichmann et al., unpublished.  

Speaker: Julian Avila, UNESP – São Paulo State University

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: The use of in-situ X-ray diffraction on conventional and additive manufactured steels

In-situ X-ray diffraction using a synchrotron source is not just a theoretical concept but a practical tool that is paramount to developing new thermomechanical treatments of structural materials through the study of phase transformation. This versatile characterization technique provides an excellent opportunity to explore science and materials engineering, and more importantly, it offers real-world applications. In this presentation, we aim to provide examples of these applications in different steels to track the austenite reversion, i.e., during tempering in high-carbon, high-silicon bearing, and maraging steels, inspiring hope for the future of our field.

Speaker: Frank de Groot, Utrecht University

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Resonant inelastic X-ray scattering of transition metal oxides

In 2p3d resonant inelastic x-ray scattering (RIXS) one scans through the 2p X-ray absorption edge and measures the low energy excitations, including phonons, magnons, plasmons and orbitons. The present experimental resolution of 20 meV allows the detailed observation of the electronic and magnetic structure. One can distinguish different types of RIXS experiments:

• Energy-resolved RIXS to determine the energy positions of the (multi)-magnons, phonons and orbitons. The 2p3d RIXS spectra of NiO [1,2], Cr impurities in alumina (Ruby) [3], magnons and phonons in Fe₂O₃ and LaFeO₃ [4]
• Momentum-resolved RIXS to determine the k-resolved magnons, phonons and orbitons, for example the k-resolved electron-hole pair band structure of LaCoO₃ [5,6].

[1] F. de Groot et al, Phys. Rev. B. 57, 14584 (1998)
[2] A. Nag et al. Phys. Rev. Lett. 124, 067202 (2020)
[3] M. Hunault et al. J. Phys. Chem. A. 122, 4399 (2018)
[4] H. Elnaggar et al. Nature Comm. 14 2749 (2023)
[5] R. Wang et al. Phys. Rev. B. 98, 035149 (2018)
[6] A. Hariki et al., Phys. Rev. B. 101, 245162 (2020)

Speaker: Francisco Gil Coury – Federal University of São Carlos (UFSCar)

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Understanding the Bioelectrocatalytic Mechanisms of Metalloenzymes by using Synchrotron Light

High entropy alloys (HEAs) have garnered significant interest due to the unique combination of properties some compositions can display including high strength, thermal stability, and good resistance to corrosion and/or wear. Understanding the phase evolution and microstructural changes in HEAs under various conditions is crucial for optimizing their performance. In-situ synchrotron X-ray diffraction (XRD) provides a powerful technique to investigate these changes in real-time with high precision. This study utilizes in-situ synchrotron XRD to examine the behavior of HEAs during thermal cycling and mechanical deformation. The results reveal detailed insights into phase transformations, strain distributions, and crystallographic texture evolution. Key findings include the identification of stable and metastable phases and the correlation between microstructural features and mechanical properties. The high resolution and rapid data acquisition capabilities of synchrotron XRD enable the observation of transient phenomena and contribute to a deeper understanding of the mechanisms governing the behavior of HEAs. This research advances the knowledge on HEAs and highlights the potential of in-situ synchrotron XRD as a valuable tool for the development of advanced materials with tailored properties.

Speaker: Miguel A.G. Aranda (Unversidad de Malaga, Spain)

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title:  Advanced diffraction and multilength scale imaging of cement hydration

Portland cements are environmentally contentious, accounting for ≈7% of anthropogenic CO₂ emissions. If cement production is considered a country, it would be the third emitter after China and USA. Thus, developing concretes with lower embodied carbon contents is central to maintaining our well-being. The main drawback of the most ambitious proposals for sustainable low-carbon cements is their slow hydration kinetics in the first three days. This is the focus of several hundreds of researchers and mine.

We are working out, in parallel, two original contributions. Firstly, the development of 4D (3D+time) cement hydration nanoimaging within a multiscale framework. The final aim is to understand cement hydration to produce binders with smaller CO₂ footprint(s) but with competitive performances. Full-field laboratory X-ray micro Computer Tomography (µCT) is widely used to study cement hydration but the best spatial resolution is about 2 µm for a Field of View (FoV) of ≈1×2 mm (H×V) with measurements taking hours. Moreover, the contrast between the different components is poor. Full-field propagation-based phase-contrast synchrotron X-ray µCT can study similar FoVs ≈1×2 mm with better spatial resolution, close to 0.50 µm. The measurements are much faster, i.e. 5-10 minutes. Unfortunately, the component contrast is only slightly better. Cement hydration can be studied with much better contrast and spatial resolution by scanning near-field ptychographic nano-computed tomography (nCT). In this case the FoVs are currently ≈200×30 µm with spatial resolution of ≈200 nm, and excellent component contrast. Even air and water can be differentiated. Unfortunately, these nCTs take currently ≈3-4 hours in optimized beamlines at third generation synchrotrons. Example of different imaging modalities for 4D nCT and µCT cement hydration will be discussed. Secondly, synchrotron techniques face competition from state-of-the-art laboratory sister approaches. In this arena, we are developing combined laboratory high energy X-ray powder diffraction (MoKa₁) and µCT. After water mixing, the cement pastes are syringed into 2.0 mm diameter glass capillaries, the ends are sealed with a polymer, and both type of data are sequentially taken. This removes the sample conditioning step which usually alters the microstructures. Selected examples will be discussed.

Speaker: Harry Westfahl Junior (LNLS Director)

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Sirius Progress and Future Directions: Status on Phase 1, and the Plans and Latest Developments for the Beamlines of Phase 2 and the Orion Project.

As we approach the completion of the first phase of the Sirius project, which includes a 3 GeV 250 pm.rad storage ring operating at 100 mA and 14 beamlines, the Brazilian Synchrotron Light Laboratory (LNLS) of CNPEM is gearing up to construct and provide the second set of beamlines to the user community. This will expand the range of energies and techniques available on Sirius and push the limits of synchrotron science in Latin America. The second phase of Sirius will feature ten new beamlines that complement the existing lineup of available techniques, as well as three new x-ray bioimaging beamlines that will be connected to the Biosafety Level 4 laboratories of the Orion project. Moreover, as part of the Sirius Phase 2, there will be a 3.5-fold increase in the electron beam current, directly improving the experiments on all beamlines. In my presentation, I will go over the scope of these projects and discuss the planning and status of these activities.

Speaker: Prof. Elisa Borfecchia (University of Turin, Chemistry Department, Via P. Giuria 7, 10125 Turin, It)

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Understanding local structure and reactivity of Cu ions in zeolite catalysts by X-ray spectroscopy

X-ray absorption (XAS) and emission (XES) spectroscopies have imposed as powerful techniques to investigate structural and chemical dynamics of metal ions hosted in porous materials, such as zeolites, for applications in the field of selective redox catalysis [1]. Analysis of the XANES and EXAFS regions in XAS spectra offers a highly complementary view with respect to diffraction-based methods guaranteeing a unique sensitivity to the local electronic and structural properties of metal centers. These are often disorderly distributed in the crystalline matrix, and occur as dynamic mixtures of different species, responding to the physico-chemical environment while undergoing a rich redox chemistry mediated by host-guest interactions. Continuous instrumental developments at synchrotron sources today enable in situ/operando XAS studies at high time and energy resolution, allowing to monitor such dynamic systems with unprecedented accuracy. In parallel, the combination with XES-based approaches greatly enhances sensitivity to the ligands of the metal centers, allowing discrimination of almost isoelectronic atomic neighbors which is difficulty achieved by XAS. In this contribution, the potential of these methods, empowered by advanced data analysis strategies and synergic integration with multi-technique laboratory characterization and computational modelling, will be exemplified by selected research results.

Presented case studies will focus on Cu-exchanged zeolites for both deNOx applications via NH3-assisted Selective Catalytic Reduction [2] as well as for C-H bond activation in light alkanes [3]. Here, the potential of Multivariate Curve Resolution (MCR) of time-resolved XANES datasets, XAS/XES combination and EXAFS Wavelet Transform analysis will be highlighted, to accurately quantify condition/composition-dependent metal speciation and therein establish robust structure-activity relationships, essential to design improved catalysts.

References

[1] S. Bordiga et al., Chem. Rev. 2013, 113, 1736. C. Garino et al., Coord. Chem. Rev. 2014, 277-278, 130. P. Glatzel et al., Coord. Chem. Rev. 2005, 249,65-95. E. Borfecchia et al., Chem. Soc. Rev. 2018, 47, 8097.

[2] A. Martini et al, Chem. Sci. 2017, 8, 6836., 10367. K. A. Lomachenko et al., J. Am. Chem. Soc. 2016, 138, 12025. C. Negri et al., J. Am. Chem. Soc. 2020, 142, 15884. Martini et al., J. Phys. Chem. Lett. 2022, 13, 6164.

[3] D. K. Pappas et al., J. Am. Chem. Soc. 2018, 140,15270-15278. Martini et al. Phys. Chem. Chem. Phys 2020, 22, 18950-18963. K. Kvande et al., Chem. Sci. 2023, in press, DOI: 10.1039/D3SC01677C.

Speaker: Graziela Cristina Sedenho (Visiting professor. Department of Chemistry. Federal University of São Carlos (UFSCar)

Link: https://us02web.zoom.us/meeting/register/tZclce2tqj4jGNCNo73BY8t8Eja5jLg31S5_

Title: Understanding the Bioelectrocatalytic Mechanisms of Metalloenzymes by using Synchrotron Light

Multicopper oxidases are metalloenzymes containing four copper ions in their catalytic sites. These enzymes have been applied as bioelectrocatalysists on electrochemical energy conversion systems, as biofuel cells, and on water splitting, as they catalyze the oxygen reduction reaction and the water oxidation reaction at very small overpotentials and under mild conditions. Understanding the electron transfer mechanisms of redox proteins has direct impact on their successful practical applications. X-ray absorption spectroscopy (XAS) is a powerful technique for studies on metalloenzymes, as it can provide information on the oxidation state of redox metal co-factors and their chemical environment, without interferences. In addition, XAS can be couple to electrochemical measurements (in situ XAS) to probe mechanisms of redox catalytic reactions under real reaction conditions. Here, aspects of the electron transfer and bioelectrocatalytic mechanisms of bilirubin oxidase (a multicopper oxidase) toward the oxygen reduction reaction and water oxidation reaction by in situ XAS are shown. Through these measurements was able to probe that copper ions act as a 3D redox active electronic bridges for the electron transfer reaction in the enzyme active site. In addition, the driving force and energy balance of the catalytic water oxidation reaction could be experimentally calculated.

Speaker: Harry Westfahl Jr., LNLS’ Director

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: New perspectives for LNLS user community science: recent results and plans of the Sirius project for 2023

LNLS resumed the user program with the first regular call for research proposals open at the end of 2022, starting a new phase of the Sirius project focused on innovative science made by the user community. From the 14 beamlines provided in the project’s first phase, six are open for regular proposal calls, four are under commissioning, and four are under construction phase, allowing diffraction, imaging, and spectroscopy experiments at scales of length from centimeters to angstroms. In this presentation, highlights of results obtained during the scientific commissioning of the first beamlines to come into operation will be presented, and the plans and perspectives of the Laboratory for 2023 will be discussed.

Speaker: Prof. João Paulo R. Marques, FZEA-USP

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: The Paradox of Solutions for Biological Sample Preparation  to Synchrotron Beamlines

The ideal sample preparation of biological tissues for Synchrotron Beamlines requires a double point of attention: preserve  the structure and avoid further ion flux among cell compartments and tissues. The sample preservation of plant anatomy and ultrastructural  using chemical fixative  solutions has been well studied for almost one century. On the other hand, synchrotron protocols for soft tissue have been achieved in the XXI century. Until now, there is no chemical fixative solution able to preserve the soft tissue structure and prevent ion mobility. Nowadays, we have developed a simple and fast workflow with cryofixation followed by cryosection and mounting the sections of plant tissue in a specific tape, named SychronTape (Botanichemical Tecnologias) in the plastic sample holder.  Before samples go to the line we verify the integrity under a light microscopy using fluorescence techniques to verify the chlorophyll preservation and then the sample holder is taken to the beamline. Regarding the methods published, the majority efforts are related to animal cells, organs and organisms but preparation of plant tissue seems a great demand to be explored, mainly when we focus on perennial plants that were low explored. So, there is any solution for fixative solutions? In this presentation we will discuss possible alternatives for preserving plant tissue for synchrotron beamline.

Speaker: Prof. Derek Peak, College of Agriculture and Bioresources, U. Saskatchewan, Canada

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: Shining Light on Phosphorus in the Environment

Phosphorus (P) is an essential plant macronutrient, and its agronomic addition via fertilizer is an integral part of the “green revolution”.  From an environmental standpoint, excessive application of P can degrade water quality (such as algal blooms, fish kills, and eutrophication). Both plant availability and environmental risk of P in agricultural systems is strongly linked to solid state P speciation in soils.  Synchrotron-based P K-edge XANES spectroscopy has successfully performed speciation on animal manures, biosolids, and soils. This method is amenable to heterogeneous sample matrices such as soils, has good detection limits, can be quantitative when calibrated, and samples with complex speciation can be deconvoluted to determine the distribution of species present.

However, P K-edge XANES spectroscopy relies upon the fact that many mineral forms of PO4 have unique spectral features or “fingerprints” that arise from a combination of (a) electronic transitions from the excited P 1s into unoccupied molecular orbitals and (b) resonance features arising from the complex scattering of the ejected P1s photoelectron with other atoms in mineral structures. This means that many organic P standards, aqueous PO4, and PO4 adsorbed on soil surfaces all have very similar spectra that cannot always be distinguished from one another.

In this presentation, several approaches for improving the speciation of P in environmental samples will be discussed. These include improving reference libraries to limit uncertainty in bulk XANES fitting, utilization of microprobe measurements to directly measure the spectral components, and using measurements at the P L-edge (130-155 eV) to provide complementary information. X-ray absorption spectroscopy at the P L-edge has some intrinsic benefits that make it well-suited to P speciation in environmental samples. Sensitivity to changes in coordination of organic-phosphate materials is far higher at the L-edge, but because P 2p transitions allow for transitions into both s and d states, the technique maintains good sensitivity to mineral phosphate species. Nonetheless, several analytical challenges (sample detection limits, spectral distortions due to fluorescence in the sample matrix, and difficulty in quantification attributed to self-absorption) have until now made bulk soft x-ray spectroscopy at the P L-edge impractical for soil research.  The recent installation of a Silicon Drift Detector (SDD) at the Canadian Light Source VLS-PGM Beamline presents some exciting opportunities that will be discussed in detail.

Speaker: Prof. Fernanda Gervasoni, Centro de Engenharias da Universidade Federal de Pelotas

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: Characterization of super-deep diamonds inclusions to unravel deep Earth`s geochemical processes

Diamond is the hardest mineral on the planet, composed essentially of inorganic carbon that is organized in tetrahedral coordination. They are refractory and resistant minerals; therefore they are considered time capsules that may preserve other deep mantle minerals inclusions that were trapped in their crystal structure during crystallization. Most diamonds are formed in the lithosphere at depths of about 130-150 km in the Earth’s interior. On the other hand, sublithospheric diamonds, that crystallized at much greater depths, are very rare and there is evidence that these diamonds form at depths of 300 km of up to 1000 km in the deep Earth (Stachel and Luth, 2015). These diamonds are known as super-deep diamonds and are the unique natural samples which enables geoscientists to study the very deep interior of the Earth, making them key tools to unravel the chemical and physical evolution of the Planet. The understanding of redox state of the deeper mantle has important implications for the geochemistry and geophysics of the Earth as a whole. The formation of the so-called super-deep diamonds, for instance, implies that deep Earth is mostly reducing (Frost and McCammon, 2008). However, it may also be possible that the deep mantle rocks become more reduced with depth and may contain metallic Fe (Frost and McCammon, 2008 and references therein). Cooper (Cu), for instance, it is an element usually found in ore deposits related to subduction zones and oxidizing conditions (e.g. Mungal, 2002). On the other hand, Cu is also present in the chemical composition of minerals trapped in super deep diamonds (Anzolini et al., 2018), that required reducing conditions to crystallized. Therefore, the aim of this project is to provide novel data to characterize the mineral inclusions found in super-deep diamonds, with focus on their redox state. The best techniques to analyze such inclusions are with non-destructive methods, such as Raman, XRD and XAFS spectroscopy using synchrotron radiation.

Speaker: Dr. Christian Wittee Lopes, Visiting Researcher, Institute of Chemistry, Universidade Federal do Rio Grande do Sul (UFRGS)

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: XAS Investigation on the evolution of active sites within and from porous materials

Zeolites and metal-organic frameworks are considered as some of the most important porous materials due to the unique characteristics of their channels, cavities, and chemical composition. It is anticipated that materials with diverse pore structures and chemical properties can lead to the development of distinct catalytic sites tailored for specific applications. This seminar will provide several examples illustrating the value of XAS in monitoring the evolution of metallic sites within molecular sieves.

Speaker: Prof. Felipe Klein Ricachenevsky, Instituto de Biociências – UFRGS

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title:  Molecular Biology, Plant Nutrition, and Synchrotron-Based Methods: a rare, yet powerful combination

Plants are primary producers, and therefore essential to multicellular organisms such as animals, including humans. Despite their role in introducing energy in the biosphere, plants are also key to the entrance of nutrients and trace elements that are essential to us in our diets. On the other hand, accumulation of harmful elements can also pose risks to our health. From the plant standpoint, balanced nutrition is also central for proper growth and productivity, as well as for defense against pathogens. Therefore, the understanding of how plants regulate uptake, distribution, and accumulation of elements in their tissues can improve rational fertilizer usage, increase productivity, and provide more nutritious foods for humans. In this talk, we will discuss current approaches to plant nutrition in our lab, including studies to understand how uptake of one nutrient affect concentrations of others, and how these interactions affect deficiency symptoms and responses; how we are using genetics to identify new genes involved in nutrient accumulation; and how synchrotron-based methods can help our research answer questions at a detailed levels that is not feasible without it. The three expertises cited in the title are often used separately, but can be quite powerful in solving problems that impact directly the field, and we should be taking advantage of the opportunities available in Brazil.

Speaker: Dr. Dimitry Doronkin – Institute for Catalysis Research and Technology (IKFT)

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: Operando XAS and XES in energy-related and environmental catalysis

Removal of nitrogen oxides via selective catalytic reduction (SCR) of NOx with NH3 still presents an important challenge in catalytic air pollution control. I will discuss application of operando hard X-ray spectroscopic techniques, in particular high energy resolved X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES), to uncover mechanisms of selective catalytic reduction of NOx over all industrially used catalyst types: Fe- and Cu-exchanged zeolites, and VOx-containing mixed oxides. Time-resolved XAS allowed monitoring oxidation state dynamics of Fe / Cu sites during transient NH3 concentration experiments and during simulation of the driving cycles. Finally, valence-to-core XES allowed identification of structure of NOx and NH3 species adsorbed on active metal sites and provided evidence for different reaction pathways over Fe-, Cu-, and VOx-based catalysts.
Correlation of time-resolved XAS data with density functional theory (DFT) allowed assignment of spectral signatures to different metal species in the zeolites and, thus, producing in situ reference data. The obtained reference datasets were finally used to map distribution of Cu (I) and Cu(II) species coordinated to different ligands in 3D in the volume of a working structured automotive catalyst with help of operando X-ray spectrotomography.

Speaker: Dr. Ann-Christin Dippel, Deutsches Elektronen-Synchrotron

Link: https://us02web.zoom.us/meeting/register/tZAtcu2rqTIiE9T4IDMyGpBWaO-eImWnEswA

Title: High-Energy X-Ray Diffraction for Physics and Chemistry at PETRA III

Abstract: DESY’s high brilliance light source PETRA III in Hamburg hosts several high-energy beamlines that provide photon energies > 50 keV. Among these, the High-Energy Diffraction Beamlines for Physics and Chemistry P07-EH2 and P21.1 focus on the study of structural disorder in materials under in situ and operando conditions. We offer a variety of core techniques incl. scattering and diffraction on single crystals as well as surfaces, interfaces and thin films, total scattering and powder diffraction, and x-ray diffraction computed tomography (XRD-CT). Besides studies in complex sample environments and at high time resolution, a common theme at the beamlines is the analysis of the diffuse scattering which contains information on the local atomic order of the sample and to represent it in terms of the atomic pair distribution function (PDF) in real space. PDF analysis reveals deviations from the periodic structure and the atomic arrangements in materials that exhibit only short-range ordering. Beamlines P21.1 and P07-EH2 specialize in total scattering methods for PDF analysis on single crystals (3D-ΔPDF) and thin films by providing dedicated instrumentation and data processing tools beyond the capabilities for traditional PDF approaches on bulk samples, e.g. powders, nanoparticle ensembles, and glasses. This presentation gives an overview of the experimental opportunities at the two beamlines and showcases a cross section of their contributions to various scientific fields ranging from correlated electron materials and fundamental chemistry to battery research, catalysis and information technology.

Speaker: Hélio C. N. Tolentino – Head of the Heterogeneous and Hierarchical Matter Division of LNLS

Link: https://us02web.zoom.us/meeting/register/tZcqc-2gqz4qG9RbSL9cskI1QCF1CAYTPtvY

Title: COMMISSIONING, FIRST EXPERIMENTS, AND OPPORTUNITIES AT THE CARNAÚBA BEAMLINE

Abstract: The X-ray nanoprobe beamline CARNAÚBA [1-4] at Sirius/LNLS has been operating for technical commissioning since November 2020 and for scientific commissioning since October 2021. The beamline design is for high-resolution multi-analytical and coherent X-ray imaging techniques over the energy domain of 2.05 to 15 keV. An all-achromatic mirror-based optics provides the nano-focused beam [5]. The beamline can operate in pink (high flux) or monochromatic (high energy resolution) mode. A 4-bounce Si(111) crystal monochromator (4CM) [6] provides the latter mode, with a resolving power of 10000 over the entire energy range. The first nanoprobe station, named TARUMÃ, provides a diversity of sample environments for in situ, operando, cryogenic, and in vivo experiments for research areas in chemistry, physics, geophysics, biology, agriculture, environment, and energy, to name a few. The sample (or sample environment) is raster-scanned through the nanoprobe to generate fast two-dimensional maps of simultaneous contrasts, which can then be combined with a rotation for computed tomography. The second nanoprobe station, which is under UHV and cryogenic, is under construction.

On behalf of the LNLS team, I will present in this lecture a few aspects of technical commissioning and the first relevant scientific cases studied. The current beamline performance is getting to the main specifications, with the predicted photon flux and a focus size close to 160×140 nm2, measured in fluorescence and transmission modes. Using X-ray ptychography, both with pink and monochromatic beam, improves the resolution down to 20 nm, as demonstrated by preliminary analysis. As far as the first experiments are concerned, I will show results in agriculture, geophysics, solar energy, along with innovative instrumentation solutions for sample environments.

[1] Tolentino, H. C. N., et al., “CARNAÚBA: The Coherent X-Ray Nanoprobe Beamline for the Brazilian Synchrotron SIRIUS/LNLS”, Journal of Physics: Conf. Series 849 (2017) 012057.

[2] Tolentino, H. C. N., et al., “TARUMÃ station for the CARNAÚBA beamline at SIRIUS/LNLS.” X-Ray Nanoimaging: Instruments and Methods IV. Vol. 11112. International Society for Optics and Photonics, 2019.

[3] Geraldes, R. R., et al., “Design and Commissioning of the TARUMÃ Station at the CARNAÚBA Beamline at SIRIUS/LNLS”, Proc. MEDSI 2020, 2021.

[4] Tolentino, H. C. N., et al., “X-ray microscopy developments at Sirius-LNLS: first commissioning experiments at the Carnauba beamline.” X-Ray Nanoimaging: Instruments and Methods V. Vol. 11839. International Society for Optics and Photonics, 2021.

[5] Moreno, G. B. Z. L., et al., “Exactly-constrained KB Mirrors for Sirius/LNLS Beamlines: Design and Commissioning of the TARUMÃ Station Nanofocusing Optics at CARNAÚBA Beamline”, Proc. MEDSI 2020, 2021.

[6] Saveri Silva, M., et al., “Four-Bounce Crystal Monochromators for the Sirius/LNLS Beamlines”, in Proc. MEDSI 2020, 2021.

Speaker: Luis Carlos Colocho Hurtarte – Post-doc Beamline ID21 European Synchrotron Radiation Facility (ESRF)

Link: https://us02web.zoom.us/meeting/register/tZYtd-GhrDgiE9PgjlwliEw8bP95O0ghUznN

Title: Synchrotron based microspectroscopy for the investigation of Carbon and Nutrient cycling in soils

Abstract: The cycling of nutrients and soil organic matter (SOM) is closely intertwined, and it is expected that changes in SOM turnover in terrestrial ecosystems as consequence of climate warming and global change are also changing the nutrient dynamics. These shifts in biogeochemical C and nutrient cycling have an important societal and economic impact on our day to day lives. An important factor to consider in biogeochemical cycling is that, most of the nutrients present in soils have organic forms associated with different SOM fractions. However, due to the lack of appropriate techniques to resolve their speciation and microspatial distribution, much of the information regarding their cycling is still unknown. Synchrotron-based techniques can aid in the understanding of the cycling of these elements, through both analyses at the macro and the microscale. Thus, my presentation aims to build the knowledge and generate discussion around the novel applications of synchrotron based techniques on soil science, and show case successful scientific cases of my own research where its combination with other techniques have yielded novel insights into SOM and nutrient cycling. Regarding the beamline ID21 is worldwide renown for X-ray micro-spectroscopy in the tender X-ray domain. It offers unique capabilities for 2D micro X-ray fluorescence mapping (µXRF, for element identification and localization) and micro X-ray absorption spectroscopy (µXAS, for speciation analysis), in the 2 – 11 keV range. This energy range allows exciting the K-edge of elements such as P, S, Cl as well as 3d transition metals. In addition, the presence and speciation of heavier metals of interest such as Pd, Ag, Sn, Cd, etc. can be probed via their L-lines. This, together with the cryo-stage option make ID21 a perfect beamline for micron scale studies of the interactions between inorganic materials and organic systems (cells, tissues, organisms, plants). Thanks to the new Extremely Brilliant Source (EBS) source and beamline refurbishment, the instrument’s performance will be further boosted offering the possibility to track changes at even lower concentrations, at higher resolution but preserving the field of view. Furthermore, it will allow us to combine the capabilities of 2D µXRF maps with single point µXAS analyses into hyperspectral imaging. Showcase studies will include, (i) the development of new approaches for bulk soil speciation of phosphorus (P), (ii) the application of correlative (cryo) microspectroscopy and nanoSIMS imaging, (iii) the use of microspectroscopy to investigate soil organic C microenvironments. In the first case, I will develop onto the use of conventional XANES spectroscopy for P research, and how alternative approaches can complement and aid in the identification of different forms of P. The second case study focuses on the combination of nano-scale Secondary Ion Mass Spectrometry (nanoSIMS) with synchrotron based µ-XRF and µ-XANES on german rock-soil interfaces and on Amazonian soils to investigate C and P cycling. The third case study will highlight new possibilities combining synchrotron-based techniques applied to soil organic C cycling. As concluding remarks, I will highlight the shortcomings of each presented technique and future possibilities using the EBS.

Speaker: Harry Westfahl Jr., LNLS’ Director

Link: https://us02web.zoom.us/meeting/register/tZclc-CpqjooHNViI6oVL2jFtIX7XeCWZe6h 

Title: The Present and Future of the LNLS User Program on Sirius

Abstract: With the beginning of the scientific commissioning in the first Sirius beamlines, the community of users of the new Brazilian synchrotron light source has had access to unprecedented experimental methods in the country, resulting in an already expressive scientific production for the current phase of the project. Furthermore, as we progress with the technical commissioning of new instruments for the beamlines in operation and the installation of the phase 1 beamlines, we will be able to reestablish the LNLS user program to pre-UVX shutdown levels. More recently, the budget required to complete phase 1 of Sirius was approved by FNDCT (National Fund for Scientific and Technological Development), bringing significant perspectives for the near-term future of the project. By receiving the financial transfers on time for the execution of the project according to our schedule, we envision reaching 2024 operating 14 light beamlines, the associated support laboratories and infrastructure for data processing, and a storage ring working within the design parameters with 350 mA. This seminar will present highlights of the new results from Sirius, the current status of the project, and the short and mid-term plans for our new synchrotron light source.

Harry Westfahl Jr. is the LNLS’ Director since 2020. He also served LNLS as Scientific Director from 2013 to 2019, as deputy scientific director from 2011 to 2012 and, as a researcher since 2001, when he joined the Laboratory after three years of postdoctoral research. Since 2013 he coordinates the project and construction of the beamlines for the new Brazilian synchrotron light source, Sirius. Its main research interests are in the physics of condensed matter systems, in the use of synchrotron radiation for the study of materials, mainly polymers and magnetic materials, and in the development of synchrotron radiation instrumentation.

Speaker: Silvia Russi, beamline scientist at the Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC National Accelerator Laboratory

Link: https://us02web.zoom.us/meeting/register/tZYoceuorzgtGNGZSbFLmd1z2fHYCm_-5ndH

Title: Hybrid Methods and Multi-Techniques at SLAC National Accelerator Laboratory

Abstract: Synchrotrons have evolved from cyclic particle accelerators splitting matter into modern powerhouses to study fundamental natural, physical, technological, and environmental processes. The SLAC National Accelerator Laboratory operated by Stanford University for the US Department of Energy hosting the Stanford Synchrotron Radiation Lightsource (SSRL), the Linac Coherent Light Source (LCLS), and the Stanford-SLAC Cryo-EM Center (S2C2), embodies the entrepreneurial and high technology essence of Silicon Valley. At SSRL, twelve different beamlines are dedicated to macromolecular crystallography, small-angle X-ray scattering, X-ray absorption spectroscopy, and X-ray fluorescence to study protein structure, protein folding, electronic and geometric phenomena, conformational changes and structure/function relationships. The LCLS X-ray free electron laser (XFEL) delivering bursts of photons at the angstrom wavelength for the femtosecond time duration allows to resolve structure and dynamics on the atomic scale. The S2C2 provides access to state-of-the-art instrumentation for specimen vitrification and cryo-EM data collection towards atomic resolution structure determination. Combining expertise across SLAC directorates is custom. The SSRL Structural Macromolecular Biology Group (SMB) and S2C2 scientists implemented combined user administration software and scheduling and developed experimental methods for time-resolved studies and micro-electron diffraction. SSRL’s 12-1 beamline and LCLS’s MFX instrument share equipment and control software (Blu-Ice) and data processing and analysis routines. Further, the new SSRL undulator microfocus 12-1 began operation in May 2020 to develop efficient fixed-target serial femtosecond diffraction experiments at MFX while methods originally developed for MFX endow SSRL new capabilities for ambient temperature and serial data collection. Through fully remote access via SSRL’s Blu-Ice software the researcher runs experiments at cryogenic and elevated temperatures under controlled humidity conditions. SSRL’s SMB team introduced a portable in-situ crystallization plate and a thermal shipping container for at room and elevated temperature experiments at X-ray diffraction and UV-Visible absorption spectroscopy studies. Combining expertise and technologies across-the-boundaries is vital for the challenging and ever more complex needs from academic, non-profit, and industry scientists pushing the frontiers in numerous scientific fields such as physics, chemistry, materials and life sciences.

Dr. Silvia Russi is a beamline scientist at the Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC National Accelerator Laboratory. Earlier in her career, Dr. Russi worked on the X-ray structure determination of bioactive organometallic compounds and inorganic complexes at the Laboratorio de Cristalografia, School of Chemistry, Universidad de la República, in her home country Uruguay. She moved then to the Structural Biology Group at the IBMB in Barcelona, Spain, to work on the structural characterization of bacterial proteins mediating the transfer of genetic material and spread of antibiotic resistance. After earning her PhD, she first joined the Diffraction Instrumentation Team at the EMBL-Grenoble Outstation, France, to conduct research on a new device for controlled crystal dehydration and then she moved to the Structural Biology Group at the ESRF where she studied new phasing strategies that exploited the anisotropy of the anomalous signal. In May 2013, she joined the SSRL, SLAC National Accelerator Laboratory, as Beamline Scientist. She provides scientific and technical support to visiting scholars and users of the macromolecular crystallography beamlines and perform research developing new experimental methods and instrumentation to accelerate protein crystallography experiments such as with the current Stanford Auto-Mounter (SAM) crystal-mounting robot and to implement fully automated, remotely-accessible, room temperature X-ray diffraction experiments.

Speaker: Cristiane B. Rodella (Paineira Group Leader)

Link: https://us02web.zoom.us/meeting/register/tZMuf-qrqjwuG9ak5qTUwrvQCsKEIXjeFkDo

Title: PAINEIRA beamline – Powder X-ray Diffraction beamline at Sirius

Abstract: Paineira beamline will be dedicated to X-ray diffraction experiments of polycrystalline materials (PXRD). It has been designed as a state-of-the-art PXRD beamline combining the benefits of brilliance and low emittance of a fourth-generation synchrotron source with sensitive, high-resolution, and fast detectors for high-quality data collection. Moreover, it will improve the trend of working in high-throughput mode at the synchrotron facility enabling efficient use of beamtime as well as reducing operational costs to provide easy access to the user. Measurements can be performed in high-resolution mode (0.008o FWHM at 15 keV) and/or fast detection (≈1s; 0.05o FWHM at 15 keV). The design optimizes the beamtime via high-throughput operation mode, using an automated system with a magazine of samples, a sample management system, and two robotic cells. Additionally, the sample holders developed will enable measurements in powder form using capillaries or self-supported samples (pellets, films) with variable temperatures during data acquisition (80K to 1273K). Furthermore, Paineira will allow PXRD experiments under in-situ and operando conditions at pressures up to 95 bar using a plug-flow capillary reactor and an automated module to control the gas flow and pressure during measurements.

Speaker: Dean Hesterberg, Soil Science Advisor and Researcher (LNLS-CNPEM)

Link: https://us02web.zoom.us/meeting/register/tZYsf-CspjovGdYn7tudAgNYPhBijkCpwsGV

Title: Multimodal Analyses at Sirius to Improve Soil Phosphorus Management

Abstract: Soils are fundamental to life as a natural resource for producing food and fiber, in addition to protecting water quality and mitigating climate change. More precise micro- to molecular-scale knowledge about the hierarchical assemblages of minerals and non-crystalline inorganic solids, biological residues, organic matter, living organisms, and pore networks that soils comprise is essential for more precise management of agricultural and environmental systems. This seminar will present ongoing research at LNLS and CNPEM that aims to increase the efficiency of plant acquisition of phosphorus. Phosphorus binding into slowly reversible forms, often termed “fixation”, is particularly problematic in highly weathered tropical soils of Brazil and renders this life-essential nutrient less available to plants over time. Our research aims to integrate information from multiple Sirius beamlines to discover how physical, chemical, and biological processes collectively contribute to this fixation, and how to diminish or reverse this process to maintain more sustainable and productive agriculture. Sirius is particularly well-suited, by design, for analyzing static and dynamic processes in soils using complementary scattering, imaging, and spectroscopy capabilities that span length scales from angstroms to centimeters. Specific examples of ongoing research will be presented, including complementary analyses of chemical and physical-structure of soil microaggregates and development of a rhizomicrocosm for in-vivo imaging of nutrient movement to a living plant root.

Dean Hesterberg is a Soil Science Advisor and Researcher at the Brazilian Synchrotron Light Laboratory (LNLS) at the Brazilian Center for Research in Energy and Materials (CNPEM) in Campinas, Brazil. He is also a William Neal Reynolds Distinguished Professor Emeritus of Soil Chemistry in the Department of Crop and Soil Sciences at North Carolina State University in the United States, where he taught and conducted research for 28 years. Dr. Hesterberg earned a B.S. degree in Plant and Soil Science from Southern Illinois University – Carbondale in 1981, an M.S. degree in Agronomy from Purdue University in 1984, and a Ph.D. degree in Soil and Environmental Sciences from the University of California – Riverside in 1988.  Before joining NC State University in 1993, he worked for Chevron Oil Field Research Company and for the Institute for Soil Fertility Research in the Netherlands. His research at LNLS focuses on developing and applying synchrotron imaging and spectroscopy techniques for understanding micro- to molecular- level dynamic processes that control behavior of phosphorus and other soil elements of importance in agricultural and environmental systems.

Speaker: Dr. Eleanor Lawrence Bright, post-doctoral researcher at the Materials Science beamline (ID11) at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France.

Link: https://us02web.zoom.us/meeting/register/tZcvdOytqjgoGNJRHha-LjS38lo4kgdcTNBw

Title:  Beam heating effects on materials science experiments: investigations at a fourth-generation synchrotron source

Abstract: Fourth-generation synchrotron X-ray sources bring increasing levels of flux and coherence, allowing unprecedented levels of resolution for a wide range of techniques, but with increasing risk of radiation damage. The high flux achievable at synchrotrons has been well known to cause damage in biological samples at around 5–20 keV; however, with increasing flux we have found that radiation effects become significant even for metal samples and high-energy X-rays through beam heating, leading to temperature increases of over 400 K with a monochromatic beam. In this seminar, we will look into an investigation of these effects performed at the ID11 beamline at the recently upgraded European Synchrotron Radiation Facility-Extremely Brilliant Source. By using thermal lattice expansion, we were able to perform in situ measurements of beam heating. Results showed significant increases in temperature for metal and ceria samples, with temperature increases as high as 400 K. By building a lumped thermodynamic model with which to compare our results, we are able to provide tool for estimating beam heating effects. These results demonstrate the importance of beam heating and provide information needed to consider, predict, and mitigate these effects.

Dr. Eleanor Lawrence Bright is a post-doctoral researcher at the Materials Science beamline (ID11) at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Eleanor earned a M.Sci. in physics at the University of Bristol, UK, where she continued to study for a Ph.D. in the Interface Analysis Centre with work focusing on uranium compounds. During this time, Eleanor developed novel samples of uranium compounds using thin films (well suited to x-ray investigations), which she used to perform synchrotron experiments with a wide range of techniques, from imaging to resonant scattering. This sparked her interest in synchrotron research and led her to moving to ID11 at the ESRF. At such a versatile beamline, Eleanor has been involved in projects on x-ray diffraction computed tomography and beamline optimisation, as well as leading her own research on topotactic oxidation and beam heating effects. With the recent upgrade of the ESRF to a fourth-generation source, Eleanor has been investigating the effects of the increased flux on materials science experiments.

Speaker:  Dr. rer. nat. Bernd R. Müller is deputy of division Micro NDE at BAM, Berlim – Germany.

Link: https://us02web.zoom.us/meeting/register/tZYpdu-urTotGdYTV3huc2okve54_IPfnuSk

Title: Microstructure characterization of materials using synchrotron X-ray refraction techniques

Abstract: X-ray refraction is an excellent tool for the characterization of the microstructure of materials. However, there are only a few (synchrotron) laboratories in the world that use this technique for material characterisation. Therefore, the seminar will first explain the basic principles of X-ray refraction and the measurement techniques installed at the hard X-ray beamline BAMline at BESSY II (Berlin, Germany). This is followed by examples of investigations on fibre-reinforced plastic composites (CFRP) as well as ceramic (Cordierite, ZrO2-SiO2) and metallic materials (Ti-6Al-4V, Inconel). Some of the investigations were carried out both ex-situ and in-situ under mechanical and thermal load. The results are correlated with the mechanical properties of the materials.

Dr. rer. nat. Bernd R. Müller studied Physics at Technische Universität Berlin where he presented his thesis in atomic physics in 1990. After several years in basic research at several European synchrotron facilities he joined the X-ray Topography Group at BAM in 1995. At BESSY II (Berlin, Germany), he has constructed the hard X-ray beamline BAMline. His activities focus on the development and application of new techniques in high-energy synchrotron topography and computed tomography. Dr. Müller is deputy of division Micro NDE at BAM. He is lecturer at Technical University Berlin. In 2015, he received the Science Award of the German Society for Non-destructive Testing (DGZfP).

Speaker: Mateus Borba Cardoso (Soft and Biological Matter Division – DMB)

Title: SARS-CoV-2 and nanomedicine: What do they have in common?

Abstract: The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) outbreak has taken the world’s attention due to the unprecedented Coronavirus Disease 2019 (COVID-19) pandemic. Therefore, the scientific community must use this moment to reflect and understand what structural characteristics give the virus such a high targeting and infectious efficiency. One of the main challenges in nanomedicine relies on designing successful targeting strategies. Currently-available nanoparticle formulations undergo non-specific interactions that result on random drug-delivery and cellular internalization profiles. These interactions deviate nanoparticles from their intended path, generate a series of off-target effects and leave them more vulnerable, for example, to phagocyte clearance. Viruses, in turn, are considered as successful examples of targeted nanoparticles that were refined through evolution. Along this talk, I will shed light on the SARS-CoV-2 and propose to look at it as a highly-efficient targeted nanoparticle, establishing an analogy with the current challenges regarding synthetic targeted nanomaterials.

Speaker: Ricardo Donizeth Reis (Extreme condition x-ray Methods of Analysis – EMA beamline group)

Title: Understanding quantum materials by X-ray techniques under extreme conditions.

Abstract: Many of today’s most exciting and potentially useful materials display states of matter that seem to be explicable only by applying quantum mechanical models. This is perhaps unsurprising as these materials can be host to a complex medley of ingredients that include many-body interactions between spins, electrons and phonons. The ground states frequently exhibit cooperative properties, such as superconductivity, charge or spin-order, Kondo effect, or exotic excitations such as Weyl or Majorana fermions. Besides the fundamental interest in understanding such materials, there is also the prospect of controlling their properties and putting them to use. Therefore, deciphering what causes quantum states of matter to form remains one of the most pressing challenges facing modern physics. In this talk, I will highlight how we can shed light on the building blocks of these materials by a combination of synchrotron techniques (x-ray absorption, diffraction, and scattering) with external pressure (hydrostatic and uniaxial), low temperature and high magnetic field in order to enable a continuous, clean and reversible tuning of quantum correlations. Our aim with this work is to drive materials through the critical region where the state of matter changes and inherently quantum effects dominate in order to probe the electronic, magnetic and structural properties as a function of lattice contraction. For that I will focus on materials that are on the verge of a phase instability with distinct crystalline structures and with electronic behavior displaying nontrivial topology.

Link: https://us02web.zoom.us/meeting/register/tZUuceyopz4sGtQL-tBw-x3YMnn5Z_InjWzm

Speaker: Ana Carolina de Mattos Zeri – Manacá (MAcromolecular micro and NAnoCrystAllography) beamline group

Title: Structural Biology at Sirius: MANACA beamline and new developments in macromolecular crystallography

Abstract: MANACÁ (Macromolecular Micro and NAno CrystAllography), first beamline in scientific commissioning at Sirius (LNLS/CNPEM), is dedicated to a range of crystallography techniques, including the most recent, serial crystallography (SX). Originally developed for use in XFELs (Xray Free Electron Lasers), SX takes advantage of micro-sized focal spots and higher flux from new light sources, as Sirius, to acquire data from hundreds of thousands of microcrystals per experiment. Experiments where samples are presented to the beam in microchip-like devices or liquid jets are already being used in other SR sources, and will be implemented at Sirius. The possibility of working with very small crystals, and also studying them at room temperature, opens new avenues for the exploration of biochemical reactions and drug development. Details of the beamline construction and commissioning, as well as first experiments, will be presented.

Link: https://us02web.zoom.us/meeting/register/tZAlcOuhrTgqHtDqKzASJYUd5dQPuB76_7Pe

Speaker: Amelie Claire Rochet – Quati (X-ray Spectroscopy with Temporal Resolution) beamline group

Title: How heterogeneous catalysis will benefit from the new synchrotron source Sirius

Abstract: Synchrotrons have been used to study heterogeneous catalysis for as long as synchrotrons have existed. Due to high penetration of X-rays and non-destructive nature of analysis, X-rays are perfectly suited for studies of catalytic phenomena under in situ/operando conditions. The development of 4^th generation synchrotron radiation facilities, such as SIRIUS [1], with improvement of brilliance and coherence properties, opens new ways towards catalysts characterisation, in particular with emerging imaging methodologies [2]. Moreover, the possibility of working with faster acquisition, better spatial resolution, higher sensitivity to various chemical and physical properties opens new avenues for the exploration of catalytic reactions. In this talk, I will present an overview of techniques that will be available at Sirius for getting a deep understanding of catalytic materials. In particular, I will focus on recent studies of chemical, morphological and structural properties of both model and real catalysts under in situ or operando conditions.

[1] Lin, L., Milas, N., Mukai, A. H. C., Resende, X. R., De Sá, F. H. (2014) J. Sync. Rad. 21 904

[2] Passos, A. R., Rochet, A., Manente, L. M., Suzana, A. F., Harder, R., Cha, W., Meneau, F. (2020) Nat. Comm. 11 4733

Link: https://us02web.zoom.us/meeting/register/tZcocOGprTgtE91zzn5EwDj1A6mpLdTGh3Xf

Speaker: Carlos A. Pérez – Carnaúba (X-Ray Nanoscopy) beamline group

Title: X-ray imaging methods and spatially-resolved X-ray spectroscopy at Sirius: potential applications in agronomy, environmental toxicology, and geochemistry

Abstract: Essential elements or micronutrients in low concentrations (often called trace elements) are required for plant, animal, and human nutrition. Nonessentials metal(loid)s are phytotoxic and/or zootoxic and are widely known as toxic elements. Regarding this, particularly important are those studies related to understanding the relationship between physicochemical properties of these materials and their toxicity that affects the ecosystems due to their extensive transformations. Environmental materials are intrinsically complex consisting of multiple solid phases where pollutants species at low concentration are heterogeneously distributed among different phases. Studies also in-vitro and in-vivo conditions would be preferentially conducted to properly understand their physicochemical properties and thus to assess the impact of these materials in complex systems. Given the complexity and heterogeneity of these microenvironments, analytical techniques capable of having a high spatial resolution, elemental sensitivity while preserving the main features of the volume under investigation, are well-preferred. In my presentation, an overview of synchrotron-based x-ray microscopy and spectromicroscopy techniques such as SR-XRF imaging, XRF tomography, and spatially-resolved XANES analysis, will be illustrated with some examples from the fields of agro-environmental, ecotoxicology, nanotoxicology, and geochemistry. A brief introduction to the Coherence X-Ray Nanofocus (CARNAÚBA) beamline will also be given, highlighting the capability for performing x-ray imaging and spectroscopic measurements on samples coming from those above-mentioned research areas. I will also describe an ongoing challenging project for conducting in-situ as well as in-vivo experiments at the root-soil environment of plants.

Link: https://us02web.zoom.us/meeting/register/tZElde2grDovHNEGnABvFB-_Igtlzzh-H1-q

Speaker: Tulio Costa. Rizuti Rocha – IPÊ (Inelastic scattering and PhotoElectron spectroscopy) beamline group

Title: Probing elementary excitations in solids and molecules with RIXS

Abstract: Atoms in crystals are not standing still, they vibrate around equilibrium positions forming displacement waves that propagate. It is the dynamics of this collective motion that enable sound to propagate through solids. Excited electrons in crystals also have rich dynamics forming a plethora of collective modes and quasiparticles involving their charge, spin, and orbital, like plasmons, excitons, magnons, polarons. A key factor to model the macroscopic properties of solids, like superconductivity, ferroelectricity, thermoelectricity among others is to determine the type of excitations present, their energy and momentum dispersion. The experimental investigation of elementary excitations is based on the inelastic scattering of probe-particles such as electrons, neutrons and photons. In this talk I will explain how the resonant inelastic X-ray scattering (RIXS) technique can be used to measure the spectrum of excitations in solids and molecules, showing examples of my current research in collaboration with LNLS users. I will also highlight the main features and status of the IPE beamline of Sirius and the RIXS endstation.

Link: https://us02web.zoom.us/meeting/register/tZYqcumqqzMiG9IIA2jA3AWjb-eJ9Rk30cQF 

Speaker: Nathaly L. Archilha – MOGNO (X-ray Micro and Nanotomography) beamline group

Title: Time-resolved experiments at Mogno beamline – applications in groundwater remediation and oil recovery

Transport in porous media is related to many fields of research and there are still several open questions, mainly related to pore scale events. The oil and gas industry has developed a lot of knowledge related to non-reactive and multiphase flow in porous media, relating pore scale events to field scale observations, which is known as upscaling. However, the same type of knowledge using a reactive fluid, covering areas such as groundwater remediation, is still very limited. In this talk, I will present results of time-resolved X-ray microtomography experiments in two different areas: enhanced oil recovery using Si nanoparticles and groundwater remediation using zero-valent iron nanoparticles. Both nanoparticles, at the time of the experiment, were well known for promoting or oil recovery or remediating groundwater for a specific family of contaminants. The proposal, in both experiments, was to investigate pore scale events, using an in-house developed flow cell, to bring new information to this field from the pore scale perspective. In addition, I will be commenting on current challenges in these areas and how Mogno’s unique design can help resolve open issues.

Link: https://us02web.zoom.us/meeting/register/tZIqc-yrqDopH9ByKQjAjd-GHINcNCKAhGgz

Speaker: Raul de Oliveira Freitas – IMBUIA (Infrared Multiscale Beamline for Ultra-resolved Imaging Applications) beamline group

Title: Infrared ultramicroscopy as a decisive tool for chemical and optical analysis of multidisciplinar nanomaterials.

Abstract: The use of infrared (IR) radiation from storage rings has brought unprecedented opportunities in label-free chemical analysis of materials. Such breakthrough was intrinsically connected to the higher brightness of the synchrotron IR compared to the classic back body thermal sources. Hence, the era of IR microscopy had started, and synchrotron facilities were meeting points for advanced spatial-spectral chemical imaging. In the last decade, the interest in sub-microscopic properties of the matter became a day-by-day demand and the classical diffraction limit of light prevented IR microscopy to follow those updates. In this presentation, the ultramicroscopy modality named synchrotron IR nanospectroscopy (SINS) is presented as an established analytical technique able to access complex optical and vibrational `properties of multidisciplinary materials at the nanoscale. In special, it will be presented the advances brought by this modality to the IR users’ program at the LNLS. Drug delivery, new energy materials, in-liquid nano-chemistry of biosystems and nano-optics of quantum materials are some of cases to be approached in this talk.

Link: https://us02web.zoom.us/meeting/register/tZcvcemtqz8sGNfZ1EAxwgkbodrajc9HSCFm