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91.
Natalie Hell Peter Beiersdorfer Gregory V. Brown Megan E. Eckart Richard L. Kelley Caroline A. Kilbourne Maurice A. Leutenegger Thomas E. Lockard F. Scott Porter Jörn Wilms 《X射线光谱测定》2020,49(1):218-233
X-ray astronomy and ground-based atomic physics have a long history of fruitful collaboration: Sound understanding of the underlying atomic physics is the key to reliable interpretation of the spectra from celestial sources; conversely, astronomical spectra have been used to benchmark and advance atomic physics. This interplay is about to become even more important as we enter a new era of high-resolution X-ray astrophysics with large effective collection area. Although high-resolution observations with the gratings on the Chandra and XMM-Newton observatories continue to drive new science, upcoming planned and proposed missions will open up new discovery space in the near future that is currently challenging to access: high-resolution spectroscopy on extended sources, in the Fe K band, and on short time scales. This review summarizes open questions in these areas and the design parameters for the Hitomi, XRISM, Athena, and Arcus observatories. The expected high quality of spectra taken with these observatories puts new constraints on the accuracy of atomic reference data required to take full advantage of the diagnostic potential of these spectra. 相似文献
92.
Drah A. Tomić N. Z. Kovačević T. Djokić V. Tomić M. Heinemann R. J. Marinković A. 《Mechanics of Composite Materials》2020,56(2):249-260
Mechanics of Composite Materials - Commercial γ ? Al2O3 particles, Al2O3 n, and synthesized Al2O3 doped with iron oxide (Al2O3 Fe) were used as reinforcements to enhance the toughness of... 相似文献
93.
ABSTRACT To understand the practical effects of pressure-transmitting media (PTM) on neutron diffraction using Paris–Edinburgh presses, diffraction patterns of MgO were collected to approximately 20?GPa using PTMs of Pb, AgCl, 4:1 methanol–ethanol (ME) mixture with and without heating, N2, and Ar. Hydrostaticity in the sample chamber estimated from the MgO 220 peak width improves in the order of Pb, AgCl, Ar, ME mixture, N2, and the heated ME mixture. Unlike previous results using diamond anvil cells, the unheated ME mixture is superior to Ar even after freezing, probably due to the cup on the anvil face. Considering these results and the sizable coherent scattering of Ne, which would show good hydrostaticity, we conclude that the ME mixture (preferably the heated one) is the best PTM in neutron experiments up to 20?GPa, while Ar can be substituted when a sample is reactive to alcohols. 相似文献
94.
Meccanica - Traditional winglets are designed as fixed devices attached at the tips of the wings. The primary purpose of the winglets is to reduce the lift-induced drag, therefore improving... 相似文献
95.
Riisager K. Borge M. J. G. Briz J. A. Carmona-Gallardo M. Forstner O. Fraile L. M. Fynbo H. O. U. Camacho A. Garzon Johansen J. G. Jonson B. Lund M. V. Lachner J. Madurga M. Merchel S. Nacher E. Nilsson T. Steier P. Tengblad O. Vedia V. 《The European Physical Journal A - Hadrons and Nuclei》2020,56(3):1-19
The European Physical Journal A - A deterministic treatment of sequential neutron emission, based on recursive equations of the residual temperatures, was applied to numerous fission cases (i.e. 49... 相似文献
96.
Siddiqui Abuzar Abid Chamkha Ali J. 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1345-1360
Journal of Thermal Analysis and Calorimetry - The steady flow of a nanofluid (mixture of titanium dioxide and water) in a rectangular channel under the influence of an inclined magnetic field is... 相似文献
97.
Nonlinear Dynamics - A complex system’s structural–dynamical interplay plays a profound role in determining its collective behavior. Irregular behavior in the form of macroscopic chaos,... 相似文献
98.
Gustavo D. Mendes Thais da Silva Pereira Júlio César Rodrigues Elaine Marcílio Santos Mariani Rafaela Souza Rodrigo Alvaro Brandão Lopes-Martins Natalícia de Jesus Antunes Ronilson Agnaldo Moreno Gilberto De Nucci 《Biomedical chromatography : BMC》2020,34(4):e4731
To assess the bioequivalence of two zolpidem hemitartrate formulations in 30 healthy volunteers. Plasma samples were obtained over a 24 h period. Plasma concentrations of zolpidem were analyzed by liquid chromatography coupled to tandem mass spectrometry with positive ion electrospray ionization using multiple reaction monitoring. Values of peak concentration (Cmax), area under curve (AUC), half-life, elimination constant, volume of distribution and clearance showed statistically significant differences when comparing women (604.34 ng h/ml, 127.36 ng/ml, 4.4 h, 0.18 1/h, 50.56 L and 8.55 L/h, respectively) and men (276.1 ng h/ml, 70.9 ng/ml, 3.3 h, 0.26 1/h, 91.42 L and 24.34 L/h, respectively), receiving the same dose (5 mg), respectively. The geometric means with corresponding 90% confidence interval for Test/Reference percentage ratios were 99.73% (CI 93.69–106.16) for Cmax, 97.44% (90% CI = 91.85–103.37%) for area under curve of plasma concentration until the last concentration observed (AUClast) and 98.30% (90% CI = 92.48–104.49) for the area under curve between the first sample (pre-dosage) and infinity (AUC0–inf). Since the 90% CI for AUClast, AUC0–inf and Cmax ratios were within the 80–125% interval proposed by the US Food and Drug Administration, it was concluded that zolpidem hemitartrate formulation (5 mg orodispersible tablet) is bioequivalent to the zolpidem hemitartrate formulation (Patz SL 5 mg sublingual tablet) with regard to both the rate and the extent of absorption. A new formulation of zolpidem 2.5 mg may be useful in women for the same clinical benefits as the 5 mg formulation in men. 相似文献
99.
Veenu Bala Yashpal S. Chhonker Richard L. Sleightholm Ayrianne J. Crawford Michael A. Hollingsworth Daryl J. Murry 《Biomedical chromatography : BMC》2020,34(8):e4859
A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (MS/MS) method was developed and validated for the quantitation of the novel CDK5 inhibitor ‘20–223' in mouse plasma. Separation of analytes was achieved by a reverse-phase ACE Excel C18 column (1.7 μm, 100 × 2.1 mm) with gradient elution using 0.1% formic acid (FA) in methanol and 0.1% FA as the mobile phase. Analytes were monitored by MS/MS with an electrospray ionization source in the positive multiple reaction monitoring mode. The MS/MS response was linear over the concentration range 0.2–500 ng/mL for 20–223. The within- and between-batch precision were within the acceptable limits as per Food and Drug Administration guidelines. The validated method was successfully applied to plasma protein binding and in vitro metabolism studies. Compound 20–223 was highly bound to mouse plasma proteins (>98% bound). Utilizing mouse S9 fractions, in vitro intrinsic clearance (CLint) was 24.68 ± 0.99 μL/min/mg protein. A total of 12 phase I and II metabolites were identified with hydroxylation found to be the major metabolic pathway. The validate method required a low sample volume, was linear from 0.2 to 500 ng/mL, and had acceptable accuracy and precision. 相似文献
100.
Yalda Liaghati Mobarhan Ronald Soong Daniel Lane Andre J. Simpson 《Magnetic resonance in chemistry : MRC》2020,58(5):427-444
Traditionally, due to different hardware requirements, nuclear magnetic resonance (NMR) has developed as two separate fields: one dealing with solids, and one with solutions. Comprehensive multiphase (CMP) NMR combines all electronics and hardware (magic angle spinning [MAS], gradients, high power Radio Frequency (RF) handling, lock, susceptibility matching) into a universal probe that permits a comprehensive study of all phases (i.e., liquid, gel-like, semisolid, and solid), in intact samples. When applied in vivo, it provides unique insight into the wide array of bonds in a living system from the most mobile liquids (blood, fluids) through gels (muscle, tissues) to the most rigid (exoskeleton, shell). In this tutorial, the practical aspects of in vivo CMP NMR are discussed including: handling the organisms, rotor preparation, sample spinning, water suppression, editing experiments, and finishes with a brief look at the potential of other heteronuclei (2H, 15N, 19F, 31P) for in vivo research. The tutorial is aimed as a general resource for researchers interested in developing and applying MAS-based approaches to living organisms. Although the focus here is CMP NMR, many of the approaches can be adapted (or directly applied) using conventional high-resolution magic angle spinning, and in some cases, even standard solid-state NMR probes. 相似文献