0 Won Weakens, Trading at More than 1,400 per Dollar By world.kbs.co.kr Published On :: Tue, 12 Nov 2024 16:43:51 +0900 [Economy] : The South Korean won weakened past the psychological threshold of 14-hundred won against the U.S. dollar on Tuesday, after Donald Trump’s victory in the U.S. presidential election last week. The South Korean currency traded at 14-hundred-three-point-five won per dollar as of 3:30 p.m. Tuesday, ...[more...] Full Article Economy
0 KOSPI Slips below 2,500 Threshold for First Time since Black Monday in August By world.kbs.co.kr Published On :: Tue, 12 Nov 2024 17:55:50 +0900 [Economy] : South Korea’s benchmark Korea Composite Stock Price Index(KOSPI) slipped below the two-thousand-500 threshold on Tuesday for the first time since August’s “Black Monday.” The KOSPI dipped 49-point-09 points, or one-point-94 percent, on Tuesday to close at two-thousand-482-point-57. In the ...[more...] Full Article Economy
0 83,000 Jobs Added in October, Slowest Growth in 4 Months By world.kbs.co.kr Published On :: Wed, 13 Nov 2024 08:29:45 +0900 [Economy] : The nation added 83-thousand jobs in October, with job growth falling below 100-thousand for the first time in four months. According to Statistics Korea on Wednesday, the number of employed people stood at 28-point-eight million last month, up 83-thousand from the same month last year. Job growth fell ...[more...] Full Article Economy
0 KOSDAQ Falls below 700 for First Time in 2 Months By world.kbs.co.kr Published On :: Wed, 13 Nov 2024 11:20:48 +0900 [Economy] : South Korea’s tech-laden KOSDAQ fell below the 700 mark during trading for the first time in two months. As of 10:12 a.m. Wednesday, the secondary KOSDAQ market stood at 697-point-94, down 12-point-58 points or one-point-77 percent from the previous day. It marks the first time the KOSDAQ has ...[more...] Full Article Economy
0 BGS receives award at the World Landslide Forum 2023 - British Geological Survey By news.google.com Published On :: Thu, 30 Nov 2023 11:06:19 GMT BGS receives award at the World Landslide Forum 2023 British Geological Survey Full Article
0 BGS releases 10K maps through updated maps portal - British Geological Survey By news.google.com Published On :: Tue, 16 May 2023 07:00:00 GMT BGS releases 10K maps through updated maps portal British Geological Survey Full Article
0 GeoClimate UKCP09 and UKCP18 - British Geological Survey By news.google.com Published On :: Tue, 30 Mar 2021 07:20:45 GMT GeoClimate UKCP09 and UKCP18 British Geological Survey Full Article
0 2024 Mine Water Energy Symposium - British Geological Survey By news.google.com Published On :: Mon, 08 Apr 2024 13:14:44 GMT 2024 Mine Water Energy Symposium British Geological Survey Full Article
0 Will 2024 be the Year of the Aurora? - British Geological Survey By news.google.com Published On :: Fri, 23 Feb 2024 17:56:24 GMT Will 2024 be the Year of the Aurora? British Geological Survey Full Article
0 UK Minerals Yearbook 2023 now available to download - British Geological Survey By news.google.com Published On :: Tue, 04 Jun 2024 11:09:40 GMT UK Minerals Yearbook 2023 now available to download British Geological Survey Full Article
0 2024 BGS summer placements scheme - British Geological Survey By news.google.com Published On :: Mon, 27 May 2024 16:11:34 GMT 2024 BGS summer placements scheme British Geological Survey Full Article
0 BGS Open Day 2024 - British Geological Survey By news.google.com Published On :: Tue, 27 Feb 2024 14:35:15 GMT BGS Open Day 2024 British Geological Survey Full Article
0 World Mineral Production 2018 to 2022 is now available - British Geological Survey By news.google.com Published On :: Tue, 09 Apr 2024 14:26:00 GMT World Mineral Production 2018 to 2022 is now available British Geological Survey Full Article
0 Synthesis and crystal structure of Ba2Y0.87(1)Mn1.71(1)Te5 By journals.iucr.org Published On :: 2024-01-01 We report the structural characterization of a new quaternary telluride, Ba2Y0.87(1)Mn1.71(1)Te5, which was synthesized by the direct reaction of the elements inside a vacuum-sealed fused-silica tube. The quaternary phase is the first member of the Ba–M–Mn–Te system (M = Sc and Y). The composition and structure of the phase were elucidated using SEM–EDX (scanning electron microscopy–energy dispersive X-ray spectrometry) and single-crystal X-ray diffraction (SCXRD) studies. The title phase is nonstoichiometric and crystallizes in the monoclinic system (space group C2/m) having the refined unit-cell parameters a = 15.1466 (8), b = 4.5782 (3), c = 10.6060 (7) Å and β = 116.956 (2)°, with two formula units (Z = 2). The pseudo-two-dimensional crystal structure of Ba2Y0.87(1)Mn1.71(1)Te5 consists of distorted YTe6 octahedra and MnTe4 tetrahedra as the building blocks of the structure. The YTe6 octahedra are arranged to form infinite one-dimensional chains by sharing edges along the [010] direction. These chains are further connected to the MnTe4 tetrahedra along the c axis to create layered two-dimensional polyanionic [Y0.87(1)Mn1.71(1)Te5]4− units. The stuffing of Ba2+ cations in between the layers of [Y0.87(1)Mn1.71(1)Te5]4− anions brings the charge neutrality of the structure. Each Ba atom in the structure sits at the centre of a distorted monocapped trigonal prism-like polyhedron of seven Te atoms. Full Article text
0 GraphT–T (V1.0Beta), a program for embedding and visualizing periodic graphs in 3D Euclidean space By journals.iucr.org Published On :: 2024-04-29 Following the work of Day & Hawthorne [Acta Cryst. (2022), A78, 212–233] and Day et al. [Acta Cryst. (2024), A80, 258–281], the program GraphT–T has been developed to embed graphical representations of observed and hypothetical chains of (SiO4)4− tetrahedra into 2D and 3D Euclidean space. During embedding, the distance between linked vertices (T–T distances) and the distance between unlinked vertices (T⋯T separations) in the resultant unit-distance graph are restrained to the average observed distance between linked Si tetrahedra (3.06±0.15 Å) and the minimum separation between unlinked vertices is restrained to be equal to or greater than the minimum distance between unlinked Si tetrahedra (3.713 Å) in silicate minerals. The notional interactions between vertices are described by a 3D spring-force algorithm in which the attractive forces between linked vertices behave according to Hooke's law and the repulsive forces between unlinked vertices behave according to Coulomb's law. Embedding parameters (i.e. spring coefficient, k, and Coulomb's constant, K) are iteratively refined during embedding to determine if it is possible to embed a given graph to produce a unit-distance graph with T–T distances and T⋯T separations that are compatible with the observed T–T distances and T⋯T separations in crystal structures. The resultant unit-distance graphs are denoted as compatible and may form crystal structures if and only if all distances between linked vertices (T–T distances) agree with the average observed distance between linked Si tetrahedra (3.06±0.15 Å) and the minimum separation between unlinked vertices is equal to or greater than the minimum distance between unlinked Si tetrahedra (3.713 Å) in silicate minerals. If the unit-distance graph does not satisfy these conditions, it is considered incompatible and the corresponding chain of tetrahedra is unlikely to form crystal structures. Using GraphT–T, Day et al. [Acta Cryst. (2024), A80, 258–281] have shown that several topological properties of chain graphs influence the flexibility (and rigidity) of the corresponding chains of Si tetrahedra and may explain why particular compatible chain arrangements (and the minerals in which they occur) are more common than others and/or why incompatible chain arrangements do not occur in crystals despite being topologically possible. Full Article text
0 Structural and biochemical characterization of the M405S variant of Desulfovibrio vulgaris formate dehydrogenase By journals.iucr.org Published On :: 2024-05-01 Molybdenum- or tungsten-dependent formate dehydrogenases have emerged as significant catalysts for the chemical reduction of CO2 to formate, with biotechnological applications envisaged in climate-change mitigation. The role of Met405 in the active site of Desulfovibrio vulgaris formate dehydrogenase AB (DvFdhAB) has remained elusive. However, its proximity to the metal site and the conformational change that it undergoes between the resting and active forms suggests a functional role. In this work, the M405S variant was engineered, which allowed the active-site geometry in the absence of methionine Sδ interactions with the metal site to be revealed and the role of Met405 in catalysis to be probed. This variant displayed reduced activity in both formate oxidation and CO2 reduction, together with an increased sensitivity to oxygen inactivation. Full Article text
0 Ternary structure of Plasmodium vivax N-myristoyltransferase with myristoyl-CoA and inhibitor IMP-0001173 By journals.iucr.org Published On :: 2024-09-18 Plasmodium vivax is a major cause of malaria, which poses an increased health burden on approximately one third of the world's population due to climate change. Primaquine, the preferred treatment for P. vivax malaria, is contraindicated in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, a common genetic cause of hemolytic anemia, that affects ∼2.5% of the world's population and ∼8% of the population in areas of the world where P. vivax malaria is endemic. The Seattle Structural Genomics Center for Infectious Disease (SSGCID) conducted a structure–function analysis of P. vivax N-myristoyltransferase (PvNMT) as part of efforts to develop alternative malaria drugs. PvNMT catalyzes the attachment of myristate to the N-terminal glycine of many proteins, and this critical post-translational modification is required for the survival of P. vivax. The first step is the formation of a PvNMT–myristoyl–CoA binary complex that can bind to peptides. Understanding how inhibitors prevent protein binding will facilitate the development of PvNMT as a viable drug target. NMTs are secreted in all life stages of malarial parasites, making them attractive targets, unlike current antimalarials that are only effective during the plasmodial erythrocytic stages. The 2.3 Å resolution crystal structure of the ternary complex of PvNMT with myristoyl-CoA and a novel inhibitor is reported. One asymmetric unit contains two monomers. The structure reveals notable differences between the PvNMT and human enzymes and similarities to other plasmodial NMTs that can be exploited to develop new antimalarials. Full Article text
0 Human transforming growth factor β type I receptor in complex with kinase inhibitor SB505124 By journals.iucr.org Published On :: 2024-10-23 The crystal structure of the intracellular domain of transforming growth factor β type I receptor (TβR1) in complex with the competitive inhibitor SB505124 is presented. The study provides insights into the structure and function of TβR1 in complex with SB505124, and as such offers molecular-level understanding of the inhibition of this critical signalling pathway. The potential of SB505124 as an avenue for therapy in cancer treatment is discussed on basis of the results. Full Article text
0 AnACor2.0: a GPU-accelerated open-source software package for analytical absorption corrections in X-ray crystallography By journals.iucr.org Published On :: AnACor2.0 significantly accelerates the calculation of analytical absorption corrections in long-wavelength crystallography, achieving up to 175× speed improvements. This enhancement is achieved through innovative sampling techniques, bisection and gridding methods, and optimized CUDA implementations, ensuring efficient and accurate results. Full Article text
0 Crystal structure of 1,10-phenanthrolinium violurate violuric acid pentahydrate By journals.iucr.org Published On :: The crystal structure of the co-crystal salt solvate 1,10-phenanthrolinium violurate violuric acid pentahydrate features a tri-periodic hydrogen-bonded network with the violurate and violuric acid residues each assembled into tapes and the phenanthrolinium cations residing in channels. Full Article text
0 AnACor2.0: a GPU-accelerated open-source software package for analytical absorption corrections in X-ray crystallography By journals.iucr.org Published On :: 2024-11-04 Analytical absorption corrections are employed in scaling diffraction data for highly absorbing samples, such as those used in long-wavelength crystallography, where empirical corrections pose a challenge. AnACor2.0 is an accelerated software package developed to calculate analytical absorption corrections. It accomplishes this by ray-tracing the paths of diffracted X-rays through a voxelized 3D model of the sample. Due to the computationally intensive nature of ray-tracing, the calculation of analytical absorption corrections for a given sample can be time consuming. Three experimental datasets (insulin at λ = 3.10 Å, thermolysin at λ = 3.53 Å and thaumatin at λ = 4.13 Å) were processed to investigate the effectiveness of the accelerated methods in AnACor2.0. These methods demonstrated a maximum reduction in execution time of up to 175× compared with previous methods. As a result, the absorption factor calculation for the insulin dataset can now be completed in less than 10 s. These acceleration methods combine sampling, which evaluates subsets of crystal voxels, with modifications to standard ray-tracing. The bisection method is used to find path lengths, reducing the complexity from O(n) to O(log2 n). The gridding method involves calculating a regular grid of diffraction paths and using interpolation to find an absorption correction for a specific reflection. Additionally, optimized and specifically designed CUDA implementations for NVIDIA GPUs are utilized to enhance performance. Evaluation of these methods using simulated and real datasets demonstrates that systematic sampling of the 3D model provides consistently accurate results with minimal variance across different sampling ratios. The mean difference of absorption factors from the full calculation (without sampling) is at most 2%. Additionally, the anomalous peak heights of sulfur atoms in the Fourier map show a mean difference of only 1% compared with the full calculation. This research refines and accelerates the process of analytical absorption corrections, introducing innovative sampling and computational techniques that significantly enhance efficiency while maintaining accurate results. Full Article text
0 Angle-resolved X-ray emission spectroscopy facility realized by an innovative spectrometer rotation mechanism at SPring-8 BL07LSU By journals.iucr.org Published On :: 2024-02-01 The X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45–135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities. Full Article text
0 A thermal deformation optimization method for cryogenically cooled silicon crystal monochromators under high heat load By journals.iucr.org Published On :: 2024-01-22 A method to optimize the thermal deformation of an indirectly cryo-cooled silicon crystal monochromator exposed to intense X-rays at a low-emittance diffraction-limited synchrotron radiation source is presented. The thermal-induced slope error of the monochromator crystal has been studied as a function of heat transfer efficiency, crystal temperature distribution and beam footprint size. A partial cooling method is proposed, which flattens the crystal surface profile within the beam footprint by modifying the cooling contact area to optimize the crystal peak temperature. The optimal temperature varies with different photon energies, which is investigated, and a proper cooling strategy is obtained to fulfil the thermal distortion requirements over the entire photon energy range. At an absorbed power up to 300 W with a maximum power density of 44.8 W mm−2 normal incidence beam from an in-vacuum undulator, the crystal thermal distortion does not exceed 0.3 µrad at 8.33 keV. This method will provide references for the monochromator design on diffraction-limited synchrotron radiation or free-electron laser light sources. Full Article text
0 Submillisecond in situ X-ray diffraction measurement system with changing temperature and pressure using diamond anvil cells at BL10XU/SPring-8 By journals.iucr.org Published On :: 2024-02-19 Recently, there has been a high demand for elucidating kinetics and visualizing reaction processes under extreme dynamic conditions, such as chemical reactions under meteorite impact conditions, structural changes under nonequilibrium conditions, and in situ observations of dynamic changes. To accelerate material science studies and Earth science fields under dynamic conditions, a submillisecond in situ X-ray diffraction measurement system has been developed using a diamond anvil cell to observe reaction processes under rapidly changing pressure and temperature conditions replicating extreme dynamic conditions. The development and measurements were performed at the high-pressure beamline BL10XU/SPring-8 by synchronizing a high-speed hybrid pixel array detector, laser heating and temperature measurement system, and gas-pressure control system that enables remote and rapid pressure changes using the diamond anvil cell. The synchronized system enabled momentary heating and rapid cooling experiments up to 5000 K via laser heating as well as the visualization of structural changes in high-pressure samples under extreme dynamic conditions during high-speed pressure changes. Full Article text
0 Enhancing electrospray ionization efficiency for particle transmission through an aerodynamic lens stack By journals.iucr.org Published On :: 2024-02-02 This work investigates the performance of the electrospray aerosol generator at the European X-ray Free Electron Laser (EuXFEL). This generator is, together with an aerodynamic lens stack that transports the particles into the X-ray interaction vacuum chamber, the method of choice to deliver particles for single-particle coherent diffractive imaging (SPI) experiments at the EuXFEL. For these experiments to be successful, it is necessary to achieve high transmission of particles from solution into the vacuum interaction region. Particle transmission is highly dependent on efficient neutralization of the charged aerosol generated by the electrospray mechanism as well as the geometry in the vicinity of the Taylor cone. We report absolute particle transmission values for different neutralizers and geometries while keeping the conditions suitable for SPI experiments. Our findings reveal that a vacuum ultraviolet ionizer demonstrates a transmission efficiency approximately seven times greater than the soft X-ray ionizer used previously. Combined with an optimized orifice size on the counter electrode, we achieve >40% particle transmission from solution into the X-ray interaction region. These findings offer valuable insights for optimizing electrospray aerosol generator configurations and data rates for SPI experiments. Full Article text
0 Sub-micrometre focusing of intense 100 keV X-rays with multilayer reflective optics By journals.iucr.org Published On :: 2024-02-22 A high-flux sub-micrometre focusing system was constructed using multilayer focusing mirrors in Kirkpatrick–Baez geometry for 100 keV X-rays. The focusing mirror system had a wide bandwidth of 5% and a high peak reflectivity of 74%. Performance was evaluated at the undulator beamline BL05XU of SPring-8, which produced an intense 100 keV X-ray beam with a bandwidth of 1%. When the light source was focused directly in both vertical and horizontal directions, the beam size was measured to be 0.32 µm (V) × 5.3 µm (H) with a flux of 1 × 1012 photons s−1. However, when a limited horizontal slit was used to form a secondary source, the focusing beam size decreased to 0.25 µm (V) × 0.26 µm (H) with a flux of 6 × 1010 photons s−1. The 200 nm line and space patterns of a Siemens star chart made of tantalum were clearly resolved by the absorption contrast of the focused beam. This 100 keV focusing system is applicable to various fields of nondestructive analyses with sub-micrometre resolutions. Full Article text
0 Development of the multiplex imaging chamber at PAL-XFEL By journals.iucr.org Published On :: 2024-03-22 Various X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens. Full Article text
0 VerSoX B07-B: a high-throughput XPS and ambient pressure NEXAFS beamline at Diamond Light Source By journals.iucr.org Published On :: 2024-03-26 The beamline optics and endstations at branch B of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source are described. B07-B provides medium-flux X-rays in the range 45–2200 eV from a bending magnet source, giving access to local electronic structure for atoms of all elements from Li to Y. It has an endstation for high-throughput X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) measurements under ultrahigh-vacuum (UHV) conditions. B07-B has a second endstation dedicated to NEXAFS at pressures from UHV to ambient pressure (1 atm). The combination of these endstations permits studies of a wide range of interfaces and materials. The beamline and endstation designs are discussed in detail, as well as their performance and the commissioning process. Full Article text
0 A sub-100 nm thickness flat jet for extreme ultraviolet to soft X-ray absorption spectroscopy By journals.iucr.org Published On :: 2024-04-09 Experimental characterization of the structural, electronic and dynamic properties of dilute systems in aqueous solvents, such as nanoparticles, molecules and proteins, are nowadays an open challenge. X-ray absorption spectroscopy (XAS) is probably one of the most established approaches to this aim as it is element-specific. However, typical dilute systems of interest are often composed of light elements that require extreme-ultraviolet to soft X-ray photons. In this spectral regime, water and other solvents are rather opaque, thus demanding radical reduction of the solvent volume and removal of the liquid to minimize background absorption. Here, we present an experimental endstation designed to operate a liquid flat jet of sub-micrometre thickness in a vacuum environment compatible with extreme ultraviolet/soft XAS measurements in transmission geometry. The apparatus developed can be easily connected to synchrotron and free-electron-laser user-facility beamlines dedicated to XAS experiments. The conditions for stable generation and control of the liquid flat jet are analyzed and discussed. Preliminary soft XAS measurements on some test solutions are shown. Full Article text
0 Scattered high-energy synchrotron radiation at the KARA visible-light diagnostic beamline By journals.iucr.org Published On :: 2024-03-26 To characterize an electron beam, visible synchrotron light is often used and dedicated beamlines at synchrotron sources are becoming a more common feature as instruments and methods for the diagnostics are, along with the accelerators, further developed. At KARA (Karlsruhe Research Accelerator), such a beamline exists and is based on a typical infrared/visible-light configuration. From experience at such beamlines no significant radiation was expected (dose rates larger than 0.5 µSv h−1). This was found not to be the case and a higher dose was measured which fortunately could be shielded to an acceptable level with 0.3 mm of aluminium foil or 2.0 mm of Pyrex glass. The presence of this radiation led to further investigation by both experiment and calculation. A custom setup using a silicon drift detector for energy-dispersive spectroscopy (Ketek GmbH) and attenuation experiments showed the radiation to be predominantly copper K-shell fluorescence and is confirmed by calculation. The measurement of secondary radiation from scattering of synchrotron and other radiation, and its calculation, is important for radiation protection, and, although a lot of experience exists and methods for radiation protection are well established, changes in machine, beamlines and experiments mean a constant appraisal is needed. Full Article text
0 The concept for hard X-ray beamline optics at SLS 2.0 By journals.iucr.org Published On :: 2024-05-31 In the scope of the latest upgrade of the Swiss Light Source, five hard X-ray beamlines will be constructed or rebuilt. To use synergies between these beamline projects, a concept is developed here for hard X-ray beamlines that is tailored to the new storage ring. Herein, this concept is described from the source, via the front end, to the beamline optics. The latter will be outlined in detail, including a new and modular concept for hard X-ray monochromators, focusing optics and heat-load management. With a simple, easy-to-operate and robust beamline design, the new beamlines will greatly profit from the increased brilliance of the new storage ring. The performance increase is up to four orders of magnitude, while the beamline concept allows for the broad application of experimental techniques, from propagation-based methods, such as phase-contrast tomography, to imaging techniques with nanometre resolution. At the same time, spectroscopy experiments are possible as well as high-performance serial X-ray crystallography. Full Article text
0 Hard X-ray operation of X-ray gas monitors at the European XFEL By journals.iucr.org Published On :: 2024-06-05 X-ray gas monitors (XGMs) are operated at the European XFEL for non-invasive single-shot pulse energy measurements and average beam-position monitoring. The underlying measurement principle is the photo-ionization of rare gas atoms at low gas pressures and the detection of the photo-ions and photo-electrons created. These are essential for tuning and sustaining self-amplified spontaneous emission (SASE) operation, machine radiation safety, and sorting single-shot experimental data according to pulse energy. In this paper, the first results from XGM operation at photon energies up to 30 keV are presented, which are far beyond the original specification of this device. Here, the Huge Aperture MultiPlier (HAMP) is used for single-shot pulse energy measurements since the standard X-ray gas monitor detectors (XGMDs) do not provide a sufficient signal-to-noise ratio, even at the highest operating gas pressures. A single-shot correlation coefficient of 0.98 is measured between consecutive XGMs operated with HAMP, which is as good as measuring with the standard XGMD detectors. An intra-train non-linearity of the HAMP signal is discovered, and operation parameters to mitigate this effect are studied. The upper repetition rate limit of HAMP operation at 2.25 MHz is also determined. Finally, the possibilities and limits for future XGM operation at photon energies up to 50 keV are discussed. Full Article text
0 The laser pump X-ray probe system at LISA P08 PETRA III By journals.iucr.org Published On :: 2024-06-06 Understanding and controlling the structure and function of liquid interfaces is a constant challenge in biology, nanoscience and nanotechnology, with applications ranging from molecular electronics to controlled drug release. X-ray reflectivity and grazing incidence diffraction provide invaluable probes for studying the atomic scale structure at liquid–air interfaces. The new time-resolved laser system at the LISA liquid diffractometer situated at beamline P08 at the PETRA III synchrotron radiation source in Hamburg provides a laser pump with X-ray probe. The femtosecond laser combined with the LISA diffractometer allows unique opportunities to investigate photo-induced structural changes at liquid interfaces on the pico- and nanosecond time scales with pump–probe techniques. A time resolution of 38 ps has been achieved and verified with Bi. First experiments include laser-induced effects on salt solutions and liquid mercury surfaces with static and varied time scales measurements showing the proof of concept for investigations at liquid surfaces. Full Article text
0 The soft X-ray spectromicroscopy beamline BL08U1A upgrade at SSRF By journals.iucr.org Published On :: 2024-08-22 Beamline BL08U1A is a soft X-ray spectromicroscopy beamline at Shanghai Synchrotron Radiation Facility (SSRF) that exhibits the capabilities of high spatial resolution (30 nm) and high energy resolving power (over 104). As a first-generation beamline of SSRF, owing to its continuous operation over the last ten years, an urgent upgrade of the equipment including the monochromator was deemed necessary. The upgrade work included the overall construction of the monochromator and replacement of the mirrors upstream and downstream of the monochromator. Based on its original skeleton, two elliptically cylinder mirrors were designed to focus the beam horizontally, which can increase the flux density by about three times on the exit slits. Meanwhile, the application of variable-line-space gratings in the monochromator demonstrates the dual functions of dispersing and focusing on the exit slits which can decrease abberations dramatically. After the upgrade of the main components of the beamline, the energy range is 180–2000 eV, the energy resolving power reaches 16333 @ 244 eV and 12730 @ 401 eV, and the photon flux measured in the experimental station is over 2.45 × 109 photons s−1 (E/ΔE = 6440 @ 244 eV). Full Article text
0 Prediction of the treatment effect of FLASH radiotherapy with synchrotron radiation from the Circular Electron–Positron Collider (CEPC) By journals.iucr.org Published On :: 2024-08-22 The Circular Electron–Positron Collider (CEPC) in China can also work as an excellent powerful synchrotron light source, which can generate high-quality synchrotron radiation. This synchrotron radiation has potential advantages in the medical field as it has a broad spectrum, with energies ranging from visible light to X-rays used in conventional radiotherapy, up to several megaelectronvolts. FLASH radiotherapy is one of the most advanced radiotherapy modalities. It is a radiotherapy method that uses ultra-high dose rate irradiation to achieve the treatment dose in an instant; the ultra-high dose rate used is generally greater than 40 Gy s−1, and this type of radiotherapy can protect normal tissues well. In this paper, the treatment effect of CEPC synchrotron radiation for FLASH radiotherapy was evaluated by simulation. First, a Geant4 simulation was used to build a synchrotron radiation radiotherapy beamline station, and then the dose rate that the CEPC can produce was calculated. A physicochemical model of radiotherapy response kinetics was then established, and a large number of radiotherapy experimental data were comprehensively used to fit and determine the functional relationship between the treatment effect, dose rate and dose. Finally, the macroscopic treatment effect of FLASH radiotherapy was predicted using CEPC synchrotron radiation through the dose rate and the above-mentioned functional relationship. The results show that the synchrotron radiation beam from the CEPC is one of the best beams for FLASH radiotherapy. Full Article text
0 Crystal structure of AlFe0.95 By journals.iucr.org Published On :: 2023-12-14 Three B2-type intermetallic AlFe1 – δ phases (0.18 < δ < 0.05) in the Al–Fe binary system were synthesized by smelting and high temperature sintering methods. The exact crystal structure for δ = 0.05 was refined by single-crystal X-ray diffraction. The amount of vacancy defects at the Fe atom sites was obtained by refining the corresponding site occupancy factor, converging to the chemical formula AlFe0.95, with a structure identical to that of ideal AlFe models inferred from powder X-ray or neutron diffraction patterns. Full Article text
0 meso-α,α-5,15-Bis(o-nicotinamidophenyl)-10,20-diphenylporphyrin n-hexane monosolvate By journals.iucr.org Published On :: 2023-12-22 The structure of the title solvated porphyrin, C56H38N8O2·C6H14, is reported. Two porphyrin molecules, one ordered and one disordered n-hexane solvate molecules are present in its asymmetric unit. The porphyrin macrocycle shows a characteristic saddle-shaped distortion, and the maximum deviation from the mean plane for non-hydrogen atoms is 0.48 Å. N—H⋯N, N—H⋯O, and C—H⋯O hydrogen bonds, as well as π–π interactions, are observed in the crystal structure. Full Article text
0 Dichlorido(4,7-dimethoxy-1,10-phenanthroline-κ2N,N')zinc(II) By journals.iucr.org Published On :: 2024-01-12 In the title complex, [ZnCl2(C14H12N2O2)], the ZnII atom is located on a twofold rotation axis and is fourfold coordinated by two chlorido ligands and a bidentate 4,7-methoxy-1,10-phenanthroline ligand in a distorted tetrahedral environment. Weak π–π stacking interactions between adjacent 4,7-dimethoxy-1,10-phenanthroline rings [centroid-to-centroid distances = 3.5969 (11) and 3.7738 (11) Å] contribute to the alignment of the complexes in layers parallel to (overline{2}01). Full Article text
0 10-Bromo-N,N-diphenylanthracen-9-amine By journals.iucr.org Published On :: 2024-03-12 In the title compound, C26H18BrN, the dihedral angles between the anthracene ring system and the phenyl rings are 89.51 (14) and 74.03 (15)°. In the extended structure, a weak C—H⋯Br interaction occurs, which generates [100] chains, but no significant π–π or C—H⋯π interactions are observed. Full Article text
0 mer-Bis(quinoline-2-carboxaldehyde 4-ethylthiosemicarbazonato)nickel(II) methanol 0.33-solvate 0.67-hydrate By journals.iucr.org Published On :: 2024-04-26 In the title compound, [Ni(C13H13N4S)2]·0.33CH3OH·0.67H2O, the NiII atom is coordinated by two tridentate quinoline-2-carboxaldehyde 4-ethylthiosemicarbazonate ligands in a distorted octahedral shape. At 100 K, the crystal symmetry is monoclinic (space group P21/n). A mixture of water and methanol crystallizes with the title complex, and one of the ethyl groups in the coordinating ligands is disordered over two positions, with an occupancy ratio of 58:42. There is intermolecular hydrogen bonding between the solvent molecules and the amine and thiolate groups in the ligands. No other significant interactions are present in the crystal packing. Full Article text
0 2-(10-Bromoanthracen-9-yl)-N-phenylaniline By journals.iucr.org Published On :: 2024-05-31 In the title compound, C26H18BrN, the central benzene ring makes dihedral angles with its adjacent anthracene ring system and pendant benzene ring of 87.49 (13) and 62.01 (17)°, respectively. The N—H moiety is sterically blocked from forming a hydrogen bond, but weak C—H⋯π interactions occur in the extended structure. Full Article text
0 Chlorido[5,10,15,20-tetrakis(quinoline-7-carboxamido)porphinato]iron(III) By journals.iucr.org Published On :: 2024-06-04 The title compound, [Fe(C84H52N12O4)Cl], crystallizes in space group C2/c. The central FeIII cation (site symmetry 2) is coordinated in a fivefold manner, with four pyrrole N atoms of the porphyrin core in the basal sites and one Cl atom (site symmetry 2) in the apical position, which completes a slightly distorted square-pyramidal environment. The porphyrin macrocycle shows a characteristic ruffled-shape distortion and the iron atom is displaced out of the porphyrin plane by 0.42 Å with the average Fe—N distance being 2.054 (4) Å; the Fe—Cl bond length is 2.2042 (7) Å. Intermolecular C—H⋯N and C—H⋯O hydrogen bonds occur in the crystal structure. Full Article text
0 (2,5-Dimethylimidazole){N,N',N'',N'''-[porphyrin-5,10,15,20-tetrayltetra(2,1-phenylene)]tetrakis(pyridine-3-carboxamide)}manganese(II) chlorobenzene disolvate By journals.iucr.org Published On :: 2024-06-04 In the title compound, [Mn(C68H44N12O4)(C5H8N2)]·2C6H5Cl, the central MnII ion is coordinated by four pyrrole N atoms of the porphyrin core in the basal sites and one N atom of the 2,5-dimethylimidazole ligand in the apical site. Two chlorobenzene solvent molecules are also present in the asymmetric unit. Due to the apical imidazole ligand, the Mn atom is displaced out of the 24-atom porphyrin mean plane by 0.66 Å. The average Mn—Np (p = porphyrin) bond length is 2.143 (8) Å, and the axial Mn—NIm (Im = 2,5-dimethylimidazole) bond length is 2.171 (8) Å. The structure displays intermolecular and intramolecular N—H⋯O, N—H⋯N, C—H⋯O and C—H⋯N hydrogen bonding. The crystal studied was refined as a two-component inversion twin. Full Article text
0 [1-(Anthracen-9-ylmethyl)-1,4,7,10-tetraazacyclododecane]chloridozinc(II) nitrate By journals.iucr.org Published On :: 2024-07-12 In the title salt, [ZnCl(C23H30N4)]NO3, the central ZnII atom of the complex cation is coordinated in a square-pyramidal arrangement by four nitrogen atoms from cyclen (1,4,7,10-tetraazacyclododecane) in the basal plane and one chlorido ligand in the apical position. The anthracene group attached to cyclen contributes to the crystal packing through intermolecular T-shaped π interactions. Additionally, the nitrate anion participates in intermolecular N—H⋯O hydrogen bonds with cyclen. Full Article text
0 Bis[2-(isoquinolin-1-yl)phenyl-κ2N,C1](2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline-κ2N,N')iridium(III) hexafluoridophosphate methanol monosolvate By journals.iucr.org Published On :: 2024-09-06 The title compound, [Ir(C15H10N)2(C19H12N4)]PF6·CH3OH, crystallizes in the C2/c space group with one monocationic iridium complex, one hexafluoridophosphate anion, and one methanol solvent molecule of crystallization in the asymmetric unit, all in general positions. The anion and solvent are linked to the iridium complex cation via hydrogen bonding. All bond lengths and angles fall into expected ranges compared to similar compounds. Full Article text
0 Ti4Fe2C0.82O0.18 By journals.iucr.org Published On :: 2024-09-30 The phase with composition Ti4Fe2C0.82O0.18, tetratitanium diiron carbide oxide, was unexpectedly synthesized by high-pressure sintering (HPS) of a stoichiometric mixture with nominal composition Ti2Fe. The Ti4Fe2C0.82O0.18 phase crystallizes in the Fdoverline{3}m space group and can be considered as the Ti2Fe structure filled with C and O atoms co-occupying the same octahedral void [occupancy ratio 0.82 (7):0.18 (7)]. The Ti4Fe2C0.82O0.18 phase is isotypic with Ti4Ni2C and Ti4Fe2O0.407, and is the first example where C and O atoms co-occupy the same site in filled Ti2Fe structures. Full Article text
0 Δ-Bis[(S)-2-(4-isopropyl-4,5-dihydrooxazol-2-yl)phenolato-κ2N,O1](1,10-phenanthroline-κ2N,N')ruthenium(III) hexafluoridophosphate By journals.iucr.org Published On :: 2024-09-17 The title compound, [Ru(C12H14NO2)2(C12H8N2)]PF6 crystallizes in the tetragonal Sohnke space group P41212. The two bidentate chiral salicyloxazoline ligands and the phenanthroline co-ligand coordinate to the central RuIII atom through N,O and N,N atom pairs to form bite angles of 89.76 (15) and 79.0 (2)°, respectively. The octahedral coordination of the bidentate ligands leads to a propeller-like shape, which induces metal-centered chirality onto the complex, with a right-handed (Δ) absolute configuration [the Flack parameter value is −0.003 (14)]. Both the complex cation and the disordered PF6− counter-anion are located on twofold rotation axes. Apart from Coulombic forces, the crystal cohesion is ensured by non-classical C—H⋯O and C—H⋯F interactions. Full Article text
0 meso-5,15-Bis[3-(isopropylidenegalactopyranoxy)phenyl]-10,20-bis(4-methylphenyl)porphyrin By journals.iucr.org Published On :: 2024-10-24 The crystal structure of a glycosylated porphyrin (P_Gal2) system, C70H70N4O12, where two isopropylidene protected galactose moieties are attached to the meso position of a substituted tetraaryl porphyrin is reported. This structure reveals that the parent porphyrin is planar, with the galactose moieties positioned above and below the porphyrin macrocycle. This orientation likely prevents porphyrin–porphyrin H-type aggregation, potentially enhancing its efficiency as a photosensitizer in photodynamic therapy. Notable non-bonding C—H⋯O and C—H⋯π interactions among adjacent P_Gal2 systems are observed in this crystal network. Additionally, the tolyl groups of each porphyrin can engage in π–π interactions with the delocalized π-systems of neighboring porphyrins. Full Article text
0 Coordination structure and intermolecular interactions in copper(II) acetate complexes with 1,10-phenanthroline and 2,2'-bipyridine By journals.iucr.org Published On :: 2024-08-23 The crystal structures of two coordination compounds, (acetato-κO)(2,2'-bipyridine-κ2N,N')(1,10-phenanthroline-κ2N,N')copper(II) acetate hexahydrate, [Cu(C2H3O2)(C10H8N2)(C12H8N2)](C2H3O2)·6H2O or [Cu(bipy)(phen)Ac]Ac·6H2O, and (acetato-κO)bis(2,2'-bipyridine-κ2N,N')copper(II) acetate–acetic acid–water (1/1/3), [Cu(C2H3O2)(C10H8N2)2](C2H3O2)·C2H4O2·3H2O or [Cu(bipy)2Ac]Ac·HAc·3H2O, are reported and compared with the previously published structure of [Cu(phen)2Ac]Ac·7H2O (phen is 1,10-phenanthroline, bipy for 2,2'-bipyridine, ac is acetate and Hac is acetic acid). The geometry around the metal centre is pentacoordinated, but highly distorted in all three cases. The coordination number and the geometric distortion are both discussed in detail, and all complexes belong to the space group Poverline{1}. The analysis of the geometric parameters and the Hirshfeld surface properties dnorm and curvedness provide information about the metal–ligand interactions in these complexes and allow comparison with similar systems. Full Article text
0 Analysis of COF-300 synthesis: probing degradation processes and 3D electron diffraction structure By journals.iucr.org Published On :: 2024-05-10 Although COF-300 is often used as an example to study the synthesis and structure of (3D) covalent organic frameworks (COFs), knowledge of the underlying synthetic processes is still fragmented. Here, an optimized synthetic procedure based on a combination of linker protection and modulation was applied. Using this approach, the influence of time and temperature on the synthesis of COF-300 was studied. Synthesis times that were too short produced materials with limited crystallinity and porosity, lacking the typical pore flexibility associated with COF-300. On the other hand, synthesis times that were too long could be characterized by loss of crystallinity and pore order by degradation of the tetrakis(4-aminophenyl)methane (TAM) linker used. The presence of the degradation product was confirmed by visual inspection, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). As TAM is by far the most popular linker for the synthesis of 3D COFs, this degradation process might be one of the reasons why the development of 3D COFs is still lagging compared with 2D COFs. However, COF crystals obtained via an optimized procedure could be structurally probed using 3D electron diffraction (3DED). The 3DED analysis resulted in a full structure determination of COF-300 at atomic resolution with satisfying data parameters. Comparison of our 3DED-derived structural model with previously reported single-crystal X-ray diffraction data for this material, as well as parameters derived from the Cambridge Structural Database, demonstrates the high accuracy of the 3DED method for structure determination. This validation might accelerate the exploitation of 3DED as a structure determination technique for COFs and other porous materials. Full Article text