B18-Core EXAFS
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Nivetha
Jeyachandran
,
Wangchao
Yuan
,
Xiang
Li
,
Akshayini
Muthuperiyanayagam
,
Stefania
Gardoni
,
Jiye
Feng
,
Qingsheng
Gao
,
Martin
Wilding
,
Peter
Wells
,
Devis
Di Tommaso
,
Cristina
Giordano
Diamond Proposal Number(s):
[29721]
Open Access
Abstract: The rising levels of CO2 have spurred growing concerns for our environment, and curbing CO2 emissions may not be practically viable with the expanding human population. One attractive strategy is the electrochemical CO2 reduction (CO2RR) into value added chemicals but because of the chemical inertness of the CO2 molecule, the electrochemical reduction requires a suitable catalyst. Cu-based catalysts have been largely investigated for CO2RR, however, the difficulty achieving a high selectivity and faradaic efficiency towards specific products, especially hydrocarbons, is still a challenge, alongside the concern over cost, stability and scarcity of the metal catalyst. The present research focuses on tuning the crystallinity of Cu nanoparticles via a green, cost-friendly, and facile method, called the urea glass route. Remarkably, the incorporation of a selected nitrogen-carbon rich source (namely, 4,5 dicyanoimidazole) at low temperatures allow the formation of an oxidized derived amorphous Cu system, whilst a second thermal treatment enables the transformation to crystalline Cu0. We found that the combination of surface Cu0 and Cu1+ (observed via XPS studies) present in our amorphous and crystalline Cu nanoparticles leads to interesting differences in the final catalytic activity when tested under CO2 reaction conditions. The combination of extended X-ray absorption fine structure (EXAFS) experiments and molecular dynamics simulations provides compelling evidence for the amorphous and metallic nature of Cu nanoparticles.
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Dec 2024
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I11-High Resolution Powder Diffraction
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Diamond Proposal Number(s):
[37697]
Abstract: Polycrystalline [FeL2][BF4]2 (L = 2,6-di(pyrazol-1-yl)isonicotinonitrile) exhibits an abrupt hysteretic spin transition near 240 K, with a shoulder on the warming branch whose appearance depends on the sample history. The freshly isolated material is a ca 60:40 mixture of triclinic (HS1) and tetragonal (HS2) high-spin polymorphs, which are structurally closely related. Both HS1 and HS2 undergo a high→low-spin transition on cooling at 230±10 K. HS1 transforms to a triclinic low-spin phase with a doubled unit cell volume (LS3), while HS2 forms a monoclinic low-spin phase (LS4) with only small changes to its unit cell dimensions. Crystals of LS3 and LS4 both convert to HS1 on rewarming. The low→high-spin transition for LS4 occurs at ca 10 K higher temperature than for LS3, explaining the asymmetric thermal hysteresis. Powder diffraction, calorimetry and magnetic data show that multiple cycling about the spin-transition leads to slow enrichment of the HS1 and LS3 phases at the expense of HS2 and LS4. That is consistent with the HS2/LS4 fraction of the polycrystalline sample undergoing rare, bifurcated HS2→(LS3+LS4) and LS4→(HS1+HS2) phase transitions. The rate of enrichment of HS1/LS3 is sample- and measurement-dependent. Three other salts of this iron(II) complex and the coordination polymer [Ag(μ-L)]BF4 are also briefly described.
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Dec 2024
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B23-Circular Dichroism
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Abstract: In today's world, the fight against counterfeiting is more critical than ever. Counterfeiting affects about 3% of global trade, posing significant risks to the economy and public safety. From fake pharmaceuticals to counterfeit currency, the need for secure and reliable authentication methods is paramount. Authentication labels are commonly used – such as holograms on bank notes and passports – but there is always a need for new unfalsifiable technologies.
This is where new groundbreaking research recently published in Applied Sciences comes into play. Led by a team of scientists from Oxford University, the University of Southampton, and Diamond Light Source, the UK’s national synchrotron, the work focuses on developing a new technology for writing and reading covert information on authentication labels. This technology leverages the unique properties of Ge2Sb2Te5 thin films, which can change their structure when exposed to specific types of laser light. By using circularly or linearly polarised laser light, the researchers can encode hidden information in these thin films. This information can then be revealed using a simple reading device, making the technology both advanced and accessible. The paper is called 'Application of Photo-Induced Chirality in Covert Authentication' and explains how photo-induced chirality in Ge2Sb2Te5 thin films can be exploited to improve authentication.
The significance of this research lies in its potential applications. Authentication labels are essential in various industries, including pharmaceuticals, electronics, and currency. The ability to encode and read covert information securely can help prevent counterfeiting and ensure the authenticity of products. Moreover, the technology's reliance on existing manufacturing methods makes it a practical solution for widespread use.
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Dec 2024
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I13-2-Diamond Manchester Imaging
I14-Hard X-ray Nanoprobe
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Kamila
Iskhakova
,
Hanna
Cwieka
,
Svenja
Meers
,
Heike
Helmholz
,
Anton
Davydok
,
Malte
Storm
,
Ivo Matteo
Baltruschat
,
Silvia
Galli
,
Daniel
Pröfrock
,
Olga
Will
,
Mirko
Gerle
,
Timo
Damm
,
Sandra
Sefa
,
Weilue
He
,
Keith
Macrenaris
,
Malte
Soujon
,
Felix
Beckmann
,
Julian
Moosmann
,
Thomas
O'Hallaran
,
Roger J.
Guillory
,
D. C. Florian
Wieland
,
Berit
Zeller-Plumhoff
,
Regine
Willumeit-Römer
Diamond Proposal Number(s):
[25078]
Open Access
Abstract: Magnesium (Mg) – based alloys are becoming attractive materials for medical applications as temporary bone implants for support of fracture healing, e.g. as a suture anchor. Due to their mechanical properties and biocompatibility, they may replace titanium or stainless-steel implants, commonly used in orthopedic field. Nevertheless, patient safety has to be assured by finding a long-term balance between metal degradation, osseointegration, bone ultrastructure adaptation and element distribution in organs. In order to determine the implant behavior and its influence on bone and tissues, we investigated two Mg alloys with gadolinium contents of 5 and 10 wt percent in comparison to permanent materials titanium and polyether ether ketone. The implants were present in rat tibia for 10, 20 and 32 weeks before sacrifice of the animal. Synchrotron radiation-based micro computed tomography enables the distinction of features like residual metal, degradation layer and bone structure. Additionally, X-ray diffraction and X-ray fluorescence yield information on parameters describing the bone ultrastructure and elemental composition at the bone-to-implant interface. Finally, with element specific mass spectrometry, the elements and their accumulation in the main organs and tissues are traced. The results show that Mg-xGd implants degrade in vivo under the formation of a stable degradation layer with bone remodeling similar to that of Ti after 10 weeks. No accumulation of Mg and Gd was observed in selected organs, except for the interfacial bone after 8 months of healing. Thus, we confirm that Mg-5Gd and Mg-10Gd are suitable material choices for bone implants.
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Nov 2024
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Valerio
Bellucci
,
Sarlota
Birnsteinova
,
Tokushi
Sato
,
Romain
Letrun
,
Jayanath C. P.
Koliyadu
,
Chan
Kim
,
Gabriele
Giovanetti
,
Carsten
Deiter
,
Liubov
Samoylova
,
Ilia
Petrov
,
Luis
Lopez Morillo
,
Rita
Graceffa
,
Luigi
Adriano
,
Helge
Huelsen
,
Heiko
Kollmann
,
Thu Nhi
Tran Calliste
,
Dusan
Korytar
,
Zdenko
Zaprazny
,
Andrea
Mazzolari
,
Marco
Romagnoni
,
Eleni Myrto
Asimakopoulou
,
Zisheng
Yao
,
Yuhe
Zhang
,
Jozef
Ulicny
,
Alke
Meents
,
Henry N.
Chapman
,
Richard
Bean
,
Adrian
Mancuso
,
Pablo
Villanueva-Perez
,
Patrik
Vagovic
Open Access
Abstract: X-ray multi-projection imaging (XMPI) is an emerging experimental technique for the acquisition of rotation-free, time-resolved, volumetric information on stochastic processes. The technique is developed for high-brilliance light-source facilities, aiming to address known limitations of state-of-the-art imaging methods in the acquisition of 4D sample information, linked to their need for sample rotation. XMPI relies on a beam-splitting scheme, that illuminates a sample from multiple, angularly spaced viewpoints, and employs fast, indirect, X-ray imaging detectors for the collection of the data. This approach enables studies of previously inaccessible phenomena of industrial and societal relevance such as fractures in solids, propagation of shock waves, laser-based 3D printing, or even fast processes in the biological domain. In this work, we discuss in detail the beam-splitting scheme of XMPI. More specifically, we explore the relevant properties of X-ray splitter optics for their use in XMPI schemes, both at synchrotron insertion devices and XFEL facilities. Furthermore, we describe two distinct XMPI schemes, designed to faciliate large samples and complex sample environments. Finally, we present experimental proof of the feasibility of MHz-rate XMPI at the European XFEL. This detailed overview aims to state the challenges and the potential of XMPI and act as a stepping stone for future development of the technique.
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Nov 2024
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B22-Multimode InfraRed imaging And Microspectroscopy
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Dukula
De Alwis Jayasinghe
,
Yinlin
Chen
,
Jiangnan
Li
,
Justyna M.
Rogacka
,
Meredydd
Kippax-Jones
,
Wanpeng
Lu
,
Sergey
Sapchenko
,
Jinyue
Yang
,
Sarayute
Chansai
,
Tianze
Zhou
,
Lixia
Guo
,
Yujie
Ma
,
Longzhang
Dong
,
Daniil
Polyukhov
,
Lutong
Shan
,
Yu
Han
,
Danielle
Crawshaw
,
Xiangdi
Zeng
,
Zhaodong
Zhu
,
Lewis
Hughes
,
Mark D.
Frogley
,
Pascal
Manuel
,
Svemir
Rudic
,
Yongqiang
Chen
,
Christopher
Hardacre
,
Martin
Schroeder
,
Sihai
Yang
Open Access
Abstract: Ammonia (NH3) production in 2023 reached 150 million tons and is associated with potential concomitant production of up to 500 million tons of CO2 each year. Efforts to produce green NH3 are compromised since it is difficult to separate using conventional condensation chillers, but in situ separation with minimal cooling is challenging. While metal–organic framework materials offer some potential, they are often unstable and decompose in the presence of caustic and corrosive NH3. Here, we address these challenges by developing a pore-expansion strategy utilizing the flexible phosphonate framework, STA-12(Ni), which shows exceptional stability and capture of NH3 at ppm levels at elevated temperatures (100–220 °C) even under humid conditions. A remarkable NH3 uptake of 4.76 mmol g–1 at 100 μbar (equivalent to 100 ppm) is observed, and in situ neutron powder diffraction, inelastic neutron scattering, and infrared microspectroscopy, coupled with modeling, reveal a pore expansion from triclinic to a rhombohedral structure on cooperative binding of NH3 to unsaturated Ni(II) sites and phosphonate groups. STA-12(Ni) can be readily engineered into pellets or monoliths without losing adsorption capacity, underscoring its practical potential.
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Nov 2024
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B16-Test Beamline
Optics
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Diamond Proposal Number(s):
[13307]
Abstract: Near-field X-ray speckle interferometry is a technique for X-ray multi-modal imaging that does not require optics and is very simple to implement. It is capable of producing absorption, phase, and scatter contrast images by utilizing random scattering media like sandpaper. The generation of these images relies on the correlation of near-field speckles, with one pattern recorded in the absence of an object and another with an object present. Our study focuses on comparing and evaluating various sub-sampling methods used in a correlation-based approach in real space. Additionally, we have analyzed the potential benefits and strengths of these sub-sampling methods in the context of X-ray speckle imaging using synchrotron radiation based X-ray source, and shown that cosine and Gaussian approximations provided superior sub-pixel delay estimations.
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Nov 2024
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B18-Core EXAFS
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Jia-Wei
Wang
,
Fengyi
Zhao
,
Lucia
Velasco
,
Maxime
Sauvan
,
Dooshaye
Moonshiram
,
Martina
Salati
,
Zhi-Mei
Luo
,
Sheng
He
,
Tao
Jin
,
Yan-Fei
Mu
,
Mehmed Z.
Ertem
,
Tianquan
Lian
,
Antoni
Llobet
Diamond Proposal Number(s):
[33134]
Open Access
Abstract: The selective photoreduction of CO2 in aqueous media based on earth-abundant elements only, is today a challenging topic. Here we present the anchoring of discrete molecular catalysts on organic polymeric semiconductors via covalent bonding, generating molecular hybrid materials with well-defined active sites for CO2 photoreduction, exclusively to CO in purely aqueous media. The molecular catalysts are based on aryl substituted Co phthalocyanines that can be coordinated by dangling pyridyl attached to a polymeric covalent triazine framework that acts as a light absorber. This generates a molecular hybrid material that efficiently and selectively achieves the photoreduction of CO2 to CO in KHCO3 aqueous buffer, giving high yields in the range of 22 mmol g−1 (458 μmol g−1 h−1) and turnover numbers above 550 in 48 h, with no deactivation and no detectable H2. The electron transfer mechanism for the activation of the catalyst is proposed based on the combined results from time-resolved fluorescence spectroscopy, in situ spectroscopies and quantum chemical calculations.
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Nov 2024
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B21-High Throughput SAXS
I03-Macromolecular Crystallography
I04-1-Macromolecular Crystallography (fixed wavelength)
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Zhihan
Bo
,
Thomas
Rowntree
,
Steven
Johnson
,
Hilman
Nurmahdi
,
Richard J.
Suckling
,
Johan
Hill
,
Boguslawa
Korona
,
Philip C.
Weisshuhn
,
Devon
Sheppard
,
Yao
Meng
,
Shaoyan
Liang
,
Edward D.
Lowe
,
Susan M.
Lea
,
Christina
Redfield
,
Penny A.
Handford
Diamond Proposal Number(s):
[31353, 7495, 12346]
Open Access
Abstract: The Notch receptor is activated by the Delta/Serrate/Lag-2 (DSL) family of ligands. The organization of the extracellular signaling complex is unknown, although structures of Notch/ligand complexes comprising the ligand-binding region (LBR), and negative regulatory region (NRR) region, have been solved. Here, we investigate the human Notch-1 epidermal growth factor-like (EGF) 20-27 region, located between the LBR and NRR, and incorporating the Abruptex (Ax) region, associated with distinctive Drosophila phenotypes. Our analyses, using crystallography, NMR and small angle X-ray scattering (SAXS), support a rigid, elongated organization for EGF20-27 with the EGF20-21 linkage showing Ca2+-dependent flexibility. In functional assays, Notch-1 variants containing Ax substitutions result in reduced ligand-dependent trans-activation. When cis-JAG1 was expressed, Notch activity differences between WT and Ca2+-binding Ax variants were less marked than seen in the trans-activation assays alone, consistent with disruption of cis-inhibition. These data indicate the importance of Ca2+-stabilized structure and suggest the balance of cis- and trans-interactions explains the effects of Drosophila Ax mutations.
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Nov 2024
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I18-Microfocus Spectroscopy
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Veronica
Clavijo Jordan
,
André F.
Martins
,
Erica
Dao
,
Kalotina
Geraki
,
Sara
Chirayil
,
Xiaodong
Wen
,
Pooyan
Khalighinejad
,
Daniel
Parrott
,
Xiaojing
Wang
,
Patricia
Gonzalez Pagan
,
Neil
Rofsky
,
Michael
Farquharson
,
A. Dean
Sherry
Open Access
Abstract: Previous studies have shown that the zinc-responsive MRI probe, GdL1, can distinguish healthy versus malignant prostate tissues based upon differences in zinc content and secretion. In this study, mice were fed chow containing low, normal, or high zinc content for 3 weeks before imaging glucose stimulated zinc secretion (GSZS) by MRI. The distribution of zinc in prostate tissue in these three groups was imaged by synchrotron radiation X-ray fluorescence (SR-XRF). A zinc deficiency caused systemic and organ-level dysregulation, weight loss, and altered zinc bioavailability. Zinc efflux from the prostate increased in parallel to dietary zinc in healthy mice but not in TRAMP mice, consistent with a lowered capacity to store dietary zinc in malignant cells. This differential zinc efflux suggests that a dietary supplement of zinc prior to a GSZS study may enhance image contrast between healthy and malignant prostate tissue, thereby improving the accuracy of prostate cancer detection in man.
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Nov 2024
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