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排序方式: 共有126条查询结果,搜索用时 140 毫秒
11.
Peter P. Gaspar Bong Hyun Boo Sarangan Chari Ashim K. Ghosh Dewey Holten Christine Kirmaier Stanislaw Konieczny 《Chemical physics letters》1984,105(2):153-157
Two transient absorptions have been detected in the 266 nm laser photolysis of 2-phenylheptamethyltrisilane in cyclohexane solution at room temperature, and their time evolution was recorded in the presence and absence of air and added trapping agents. The shorter-lived 440 nm transient (t1/2 < 20μs) is tentatively assigned to the silylene :SiMePh and the more persistent 380 nm transient to the disilene MePhSiSiMePh. The reactivity of this silylene is much lower than had been expected. 相似文献
12.
13.
H. J. Booβ 《Colloid and polymer science》1959,164(1):22-26
Zusammenfassung Es werden mehrere Prüfverfahren beschrieben, die zur Kennzeichnung technischer Kolloidgraphite verwendet werden k?nnen. Durch
Flockung und Elektrophorese k?nnen Aquadag und Hydrokollag qualitativ unterschieden werden. Durch Chromatographie werden Best?ndigkeit
und Netzf?higkeit beurteilt. Schlie?lich, bieten die Viskosit?tsmessungen die M?glichkeit, die Flie?eigenschaften qualitativ
zu erfassen. 相似文献
14.
15.
Recently Choe et al. have introduced the notion of dual Berezin transforms and used it to obtain new characterizations of the Carleson measures for the weighted Bergman spaces over the unit ball in C n . Continuing our investigation on the Hardy spaces, we obtain new characterizations of the Carleson measures for the Hardy spaces by means of the dual Poisson–Szegö transforms introduced by Koosis. Compared with the results for the weighted Bergman spaces, our results for the Hardy spaces not only show an similarity, but also reveal a new characterization. 相似文献
16.
Kwang Taek Kim Boo Jeon Han Min Kuk Kim Young Ho Kim Byeong Ha Lee Kyung Jae Cho 《Fiber and Integrated Optics》2013,32(4):265-277
Abstract Two types of 4 × 4 plastic optical fiber star couplers incorporated with a polymer waveguide as the optical power distributor are proposed, and their high performances are demonstrated. The characteristics of the proposed star coupler are investigated based on ray optics, and its power distribution performance is evaluated in terms of the flatness of the coupling ratio and the amount of the excess loss. Under the best conditions, the flatness of the coupling ratio and the excess loss of the fabricated device have been obtained as 2.0 dB and 2.5 dB, respectively. 相似文献
17.
Jikun Li Xinxin Feng Wei Zhu Nikita Oskolkov Tianhui Zhou Boo Kyung Kim Noman Baig Prof. Michael T. McMahon Prof. Eric Oldfield 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):264-271
Diamagnetic chemical exchange saturation transfer (CEST) contrast agents offer an alternative to Gd3+‐based contrast agents for MRI. They are characterized by containing protons that can rapidly exchange with water and it is advantageous to have these protons resonate in a spectral window that is far removed from water. Herein, we report the first results of DFT calculations of the 1H nuclear magnetic shieldings in 41 CEST agents, finding that the experimental shifts can be well predicted (R2=0.882). We tested a subset of compounds with the best MRI properties for toxicity and for activity as uncouplers, then obtained mice kidney CEST MRI images for three of the most promising leads finding 16 (2,4‐dihydroxybenzoic acid) to be one of the most promising CEST MRI contrast agents to date. Overall, the results are of interest since they show that 1H NMR shifts for CEST agents—charged species—can be well predicted, and that several leads have low toxicity and yield good in vivo MR images. 相似文献
18.
Many different types of urine proteome studies have been done, but urine glycoprotein studies are insufficient. Therefore, we studied the glycoproteins from rat urine, which could be used to identify biomarkers in an animal model. First, urinary proteins were prepared by using the dialysis and lyophilizing methods from rat urine. Glycoproteins enriched with lectin affinity purification, concanavalin A, jacalin and wheat germ agglutinin from the urinary proteins were separated by means of reverse-phase fast protein LC (FPLC) or 1-D PAGE. Each FPLC fraction and 1-D PAGE gel band were trypsin-digested and analyzed by means of nanoLC-MS/MS. LC-MS/MS analyses were carried out by using linear ion trap MS. A total of 318 rat urinary glycoproteins were identified from the FPLC fractions and gel bands; approximately 90% of identified proteins were confirmed as glycoproteins in Swiss-Prot. Many glycoproteins, known as biomarkers, including C-reactive protein, uromodulin, amyloid beta A4 protein, alpha-1-inhibitor 3, vitamin D-binding protein, kallikrein 3 and fetuin-A were identified in this study. By studying urinary glycoproteins collected from rat, these results may help to assist in identifying urinary biomarkers regarding various types of disease models. 相似文献
19.
Tiegang Liu A. W. Chowdhury & Boo Cheong Khoo 《advances in applied mathematics and mechanics.》2011,3(5):611-632
In this work, the modified ghost fluid method is developed to deal with
2D compressible fluid interacting with elastic solid in an Euler-Lagrange
coupled system. In applying the modified Ghost Fluid Method to treat the
fluid-elastic solid coupling, the Navier equations for elastic solid are
cast into a system similar to the Euler equations but in Lagrangian coordinates.
Furthermore, to take into account the influence of material deformation and
nonlinear wave interaction at the interface, an Euler-Lagrange Riemann problem
is constructed and solved approximately along the normal direction of the
interface to predict the interfacial status and then define the ghost fluid
and ghost solid states. Numerical tests are presented to verify the resultant
method. 相似文献
20.
In this study, the heat transfer performance of a multi-channel volumetric air receiver for a solar power tower was numerically analyzed. The governing equations, including the solar radiation heat flux, conduction, convection and radiation heat transfer for a single channel, were solved on the basis of valid related references and a methodology that can predict the temperature distribution of the receiver wall and the heat transfer fluid for specific dimensions and input conditions. Furthermore, a mathematical model of the effectiveness of the receiver was derived from an analysis of the temperature profiles of the wall and the heat transfer fluid. The receiver effectiveness as an appropriate criterion to assess economic feasibility regarding geometric size was investigated, as it would be applied to the design process of the receiver. The main parameters for the thermal performance simulations described in this paper are the air mass flow rate, receiver length and the influence of these parameters on the heat transfer performance from the viewpoint of receiver efficiency and effectiveness. 相似文献