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排序方式: 共有6013条查询结果,搜索用时 16 毫秒
991.
Matthias Meier Dr. Julia Kennedy‐Darling Se Hoon Choi Eric M. Norstrom Dr. Sangram S. Sisodia Prof. Dr. Rustem F. Ismagilov Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(8):1487-1489
Small with control : For miniaturization of protein aggregation experiments the interfacial chemistry must be controlled to avoid protein aggregation caused by interfacial adsorption. Plug‐based microfluidics with defined surface chemistry (see schematic picture) can then be used to perform hundreds of aggregation experiments with volume‐limited samples, such as cerebrospinal fluid from mice.
992.
993.
Choi JH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2000,56(8):1653-1660
The emission and excitation spectra of cis-[Cr(cyclam)(N3)2](N3) (cyclam = 1,4,8,11-tetraazacyclotetradecane) taken at 77 K are reported. The infrared and visible spectra at room temperature are also measured. The vibrational intervals due to the electronic ground state are extracted from the far-infrared and emission spectra. The ten electronic bands due to spin-allowed and spin-forbidden transitions are assigned. Using the observed transitions, a ligand field analysis has been performed to determine the bonding property of azido group in the chromium(III) complex. It is found that azide ligand has weak sigma- and pi-donor properties toward chromium(III) ion. The zero-phonon line in the excitation spectrum splits into two components by 249 cm(-1), and the large 2Eg splitting can be reproduced by the ligand field theory. 相似文献
994.
By Ailín Ruiz de Zárate Daniel G. Alfaro Vigo ré Nachbin Wooyoung Choi 《Studies in Applied Mathematics》2009,122(3):275-294
A higher-order strongly nonlinear model is derived to describe the evolution of large amplitude internal waves over arbitrary bathymetric variations in a two-layer system where the upper layer is shallow while the lower layer is comparable to the characteristic wavelength. The new system of nonlinear evolution equations with variable coefficients is a generalization of the deep configuration model proposed by Choi and Camassa [ 1 ] and accounts for both a higher-order approximation to pressure coupling between the two layers and the effects of rapidly varying bottom variation. Motivated by the work of Rosales and Papanicolaou [ 2 ], an averaging technique is applied to the system for weakly nonlinear long internal waves propagating over periodic bottom topography. It is shown that the system reduces to an effective Intermediate Long Wave (ILW) equation, in contrast to the Korteweg-de Vries (KdV) equation derived for the surface wave case. 相似文献
995.
In this paper we show that the Bishop–Phelps–Bollobás theorem fails for bilinear forms on l1×l1, while it holds for linear operators from l1 to l∞. 相似文献
996.
We continue the investigation of notions of approximate amenability that were introduced in work of the second and third authors together with R.J. Loy. It is shown that every boundedly approximately contractible Banach algebra has a bounded approximate identity, and that the Fourier algebra of the free group on two generators is not operator approximately amenable. Further examples are obtained of ?1-semigroup algebras which are approximately amenable but not amenable; using these, we show that bounded approximate contractibility need not imply sequential approximate amenability. Results are also given for Segal algebras on locally compact groups, and algebras of p-pseudo-functions on discrete groups. 相似文献
997.
Yutae Lee Tai Suk Kim Ho-Shin Cho Dan Keun Sung Bong Dae Choi 《Mathematical and Computer Modelling》2009,49(3-4):423-431
We model and analyze an elevator system during up-peak. We study the round-trip time, whose distribution depends strongly on the number of passengers waiting at the lobby, as well as the number of stops and the highest reversal floor. The distribution functions of the passenger queue length in the lobby, the round-trip time, the waiting time, the ride time and the journey time are derived. 相似文献
998.
Highly sensitive single-walled carbon nanotube-field effect transistor (SWNT-FET) devices, which detect protein adsorptions and specific protein-protein interactions at 1 pM concentrations, have been achieved. The detection limit has been improved 104-fold compared to the devices fabricated by photolithography. The substantially increased sensitivity is mainly due to the increased Schottky contact area which accommodates relatively more numbers of proteins even at very low concentration. The augmented number of proteins adsorbed on a device induces instant modulation of the work function of metal contact electrodes, which eventually changes the conductance of the device. Such devices have been attained by addressing metal electrodes on network-type SWNTs using a shadow mask on a tilted angle sample stage. The shadow mask allows metals to penetrate underneath the mask efficiently, therefore forming a thin and wide Schottky contact area on SWNT channels. 相似文献
999.
Yi HB Diefenbach M Choi YC Lee EC Lee HM Hong BH Kim KS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(18):4885-4892
To understand the self-assembly process of the transition metal (TM) nanoclusters and nanowires self-synthesized by hydroquinone (HQ) and calix[4]hydroquinone (CHQ) by electrochemical redox processes, we have investigated the binding sites of HQ for the transition-metal cations TM(n+)=Ag(+), Au(+), Pd(2+), Pt(2+), and Hg(2+) and those of quinone (Q) for the reduced neutral metals TM(0), using ab initio calculations. For comparison, TM(0)-HQ and TM(n+)-Q interactions, as well as the cases for Na(+) and Cu(+) (which do not take part in self-synthesis by CHQ) are also included. In general, TM-ligand coordination is controlled by symmetry constraints imposed on the respective orbital interactions. Calculations predict that, due to synergetic interactions, silver and gold are very efficient metals for one-dimensional (1D) nanowire formation in the self-assembly process, platinum and mercury favor both nanowire/nanorod and thin film formation, while palladium favors two-dimensional (2D) thin film formation. 相似文献
1000.
Yoon SH Moon JH Choi KM Kim MS 《Rapid communications in mass spectrometry : RCM》2006,20(14):2201-2208
A deflection system consisting of four deflectors was designed and used to reduce the interference from post-source decay (PSD) product ions in photodissociation (PD) tandem time-of-flight (TOF) mass spectrometry. For simple protonated peptides generated by matrix-assisted laser desorption/ionization, the presence of PSD product ions at the laser irradiation spot was found to noticeably alter the minor peaks in the PD spectra even though the major ones were hardly affected. Other benefits from the use of the deflection system such as the improvement in the resolving power in PSD tandem mass spectra are discussed. 相似文献