We have used the EBIT-I electron beam ion trap at the Lawrence Livermore National Laboratory and a duplicate Orion High Resolution X-ray Spectrometer (OHREX) to measure the relative efficiency of a spherically bent quartz (101̄1) crystal (2d = 6.687 Å) and a spherically bent germanium (111) crystal (2d = 6.532 Å). L-shell X-ray photons from highly charged molybdenum ions generated in EBIT-I were simultaneously focussed and Bragg reflected by each crystal, both housed in a single spectrometer, onto a single CCD X-ray detector. The flux from each crystal was then directly compared. Our results show that the germanium crystal has a reflection efficiency significantly better than the quartz crystal, however, the energy resolution is significantly worse. Moreover, we find that the spatial focussing properties of the germanium crystal are worse than those of the quartz crystal. Details of the experiment are presented, and we discuss the advantages of using either crystal on a streak-camera equipped OHREX spectrometer.
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J Synchrotron Radiat
January 2025
National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.
Anal Chim Acta
January 2025
Institute of Eco-Environmental Forensics, School of Environmental Science and Engineering, Shandong University (Qingdao), No. 72, Binhai Road, Jimo District, Qingdao, Shandong Province, 266237, China.
Background: Hydrogel microspheres with monodisperse and homogeneous dimensions have potential application in the field of three-dimensional (3D) cell culture due to its ability to provide a similar microenvironment. Currently, alginate hydrogel microspheres (AHMs) have received much attention due to the favorable properties of alginate such as biocompatibility, inexpensiveness, nontoxicity, and biodegradability. The fabrication methods of AHMs mainly include extrusion, electrostatic dripping and microfluidic chip techniques.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.
Ca ions play crucial roles in regulating many chemical and biological processes, but their impact on lipid bilayer membranes remains elusive, especially when the impacts on the two leaflets are asymmetrical. Using a recently developed multisite Ca model, we performed molecular dynamics simulations to study the impact of Ca on the properties of membranes composed of POPC and POPS and observed that both the structure and fluidity of the membranes were significantly affected. In particular, we examined the influence of asymmetrically distributed Ca on asymmetric lipid bilayers and found that imbalanced stress in the two leaflets was generated, with the negatively charged leaflet on the Ca-rich side becoming more condensed, which in turn induced membrane curvature that bent the membrane away from the Ca-rich side.
View Article and Find Full Text PDFChemistry
January 2025
Laboratory for Chemistry and Life Science, Institute of Integrated Research, Institute of Science Tokyo, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan.
Photocontrol over host frameworks is an elegant way to manipulate host-guest composites, yet the majority of previous systems suffer from long irradiation time and narrow guest scope, and are restricted to intramolecular photoreactions in organic solvents. Herein we present a photolockable polyaromatic capsule with high guest binding abilities in water. The capsule assembles from bent amphiphiles featuring two 2-subsutituted anthracene panels, which shows high stability against dilution and undergoes intermolecular [4+4] photo-oligomerization upon short light irradiation (<10 min).
View Article and Find Full Text PDFRev Sci Instrum
August 2024
University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA.
A high-fidelity synthetic diagnostic has been developed for the ITER core x-ray crystal spectrometer diagnostic based on x-ray ray tracing. This synthetic diagnostic has been used to model expected performance of the diagnostic, to aid in diagnostic design, and to develop engineering tolerances. The synthetic model is based on x-ray ray tracing using the recently developed xicsrt ray tracing code and includes a fully three-dimensional representation of the diagnostic based on the computer aided design.
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