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排序方式: 共有850条查询结果,搜索用时 46 毫秒
41.
Masahiro Yamashita Daisuke Kawakami Satoshi Matsunaga Yoshio Nakayama Mari Sasaki Shinya Takaishi Fumiyasu Iwahori Hitoshi Miyasaka Ken‐ichi Sugiura Yoshiki Wada Hiroshi Miyamae Hiroyuki Matsuzaki Hiroshi Okamoto Hisaaki Tanaka Kazuhiro Marumoto Shin‐ichi Kuroda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2004,116(36):4867-4871
42.
Mihai Mari 《Journal de Mathématiques Pures et Appliquées》2002,81(12):109-1239
We are interested in the existence of travelling-waves for the nonlinear Schrödinger equation in RN with “ψ3−ψ5”-type nonlinearity. First, we prove an abstract result in critical point theory (a local variant of the classical saddle-point theorem). Using this result, we get the existence of travelling-waves moving with sufficiently small velocity in space dimension N4. 相似文献
43.
We have developed a new sample injection method for capillary electrophoresis (CE) that reduces the required migration time. We demonstrated a pressurization technique that was performed with buffer in the outlet after the electrokinetic sample injection with no buffer in the outlet. To reduce the migration time, the sample injection had to be performed with no buffer in the outlet; water should be pressurized while the buffer is in the outlet. Though the resolution was slightly decreased using this method, the addition of a separation carrier (curdlan) to the run buffer restored the resolution without delaying the migration time. The use of our new sample injection method combined with our high-quality separation carrier will enable us to improve the efficiency of the high-throughput screening (HTS) system for proteome analysis. 相似文献
44.
Watanabe S Sonobe M Arai M Tazume Y Matsuo T Nakamura T Yoshida K 《Chemical communications (Cambridge, England)》2002,(23):2866-2867
A gold nanoparticle surface-modified with amide ligands shows enhanced optical sensing of anions: the detection limit is increased by about three orders of magnitude higher than that originally expected from the anion binding ability of neutral amide ligands. 相似文献
45.
T. Yoshii H. Hara A. Kawamori K. Akabori M. Iwaki S. Itoh 《Applied magnetic resonance》1999,16(4):565-580
Light-induced spin-polarized radical pairs, P700+A1 ? in spinach photosystem (PS) I particles and P680+QA ? in Zn-substituted PS II core complexes, in oriented membranes were studied by pulsed electron paramagnetic resonance (EPR). Based on the determined distance of 25.2 ± 0.2 Å between P700 and A1, the angular dependence of the spin-polarized electron spin echo envelope modulation (ESEEM) spectra on the magnetic field suggests that the angle between $R_{P700 - {\rm A}_1 } $ , the radius-vector connecting P700 and A1, and the membrane normaln was 24 ± 4° in PS I particles. Obtained angle and distance of P700-A1 axis suggested QK side in the molecular geometry of cofactors presented in a recent X-ray crystallography of cyanobacterial PS I reaction center to be an active branch of electron transfer. The distance between P680 and QA was determined to be 27.4 ± 0.3 Å for a nonoriented PS II. The angle between $R_{P680 - Q_{\rm A} } $ , the radius-vector connecting P680 and QA, andn was determined to be 21 ± 5°. The angle of P680-QA axis was close to that of 20° of P870-QA axis reported in X-ray analysis of the purple bacterial reaction center crystal. 相似文献
46.
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48.
This paper describes a novel, sensitive detection system for biomolecules (DNA and proteins etc.) that is integrated in a lab-on-a-chip utilizing optical compact discs (CDs) and bio-nanofibers. The new method comprises a microchannel containing CD grating that confines fragments of unique bacterial cellulose fibrils (BC), which have nanometre scale fibers and holes. A maximum of six times higher sensitivity to detect DNA was obtained with this CD and BC system compared to a conventional method. We also demonstrate an effective light-confining effect for biological application with the new method. 相似文献
49.
Canevali C Mari CM Mattoni M Morazzoni F Nodari L Ruffo R Russo U Scotti R 《The journal of physical chemistry. B》2005,109(15):7195-7202
The mechanism of NO interaction with nanosized Ru(Pd,Pt)-doped SnO(2) was studied by electron paramagnetic resonance, M?ssbauer, and electric resistance measurements. Three steps were proposed for the reaction between the semiconductor oxide and the gaseous component: (i) the formation of bielectronic oxygen vacancies (V(o)) in SnO(2); (ii) their single-ionization (V(o)(*)) with injection of electrons into the SnO(2) conduction band; (iii) the subsequent transfer of electrons from V(o)(*) to [Ru(Pd,Pt)](4+). The last process induces the formation of further oxygen vacancies which reduce the transition metal centers to lower oxidation states; the redox processes is enhanced and the electrical resistance in transition metal-doped SnO(2) is stronger modified with respect to the undoped material. 相似文献
50.
Sugita M Yamaguchi A Yamagiwa N Handa S Matsunaga S Shibasaki M 《Organic letters》2005,7(23):5339-5342
[reaction, structure: see text] Chiral Y{N(SiMe3)2}3/linked-BINOL catalyst generated Y-enolate in situ from various hydroxyketones (R2 = aryl, heteroaryl). Beta-amino-alpha-hydroxy ketones (R1 = aryl, heteroaryl, alkenyl) were obtained syn-selectively (up to 96/4) in high ee (up to 98%) and good yield (up to 98% yield). 相似文献