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排序方式: 共有393条查询结果,搜索用时 15 毫秒
81.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu X 《Physical review letters》1986,57(25):3140-3143
82.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu XQ 《Physical review letters》1986,57(20):2500-2503
83.
The luminescence lifetime of TbL2 with a pendant 15-crown-5 increased by 65% to 2.95 ms with an [Na+] concentration of 0.13 M in aqueous solution; the maximum amplification of the luminescence intensity of TbL1 containing aza-15-crown-5 reached a factor of 47 upon addition of the aromatic antenna p-chlorobenzoate 1. 相似文献
84.
Transition metal-catalyzed [m+n+o] carbocyclization reactions provide powerful methods for the construction of complex polycyclic systems that are generally not accessible through classical pericyclic reactions. We have developed the first regio- and enantioselective crossed intermolecular rhodium-catalyzed [2+2+2] carbocyclization of carbon- and heteroatom-tethered 1,6-enynes with unsymmetrical 1,2-disubstituted alkynes. This study clearly delineates the ligand requirements for obtaining excellent regio- and enantioselectivity. Furthermore, the ability to utilize various electron-withdrawing groups, and to introduce quaternary carbon stereogenic centers, provides the level of versatility necessary for its application to target-directed synthesis. Additional studies on the development and application of this novel methodology to the total synthesis of natural products are currently underway. 相似文献
85.
Label-free cell separation and sorting in microfluidic systems 总被引:2,自引:0,他引:2
Daniel R. Gossett Westbrook M. Weaver Albert J. Mach Soojung Claire Hur Henry Tat Kwong Tse Wonhee Lee Hamed Amini Dino Di Carlo 《Analytical and bioanalytical chemistry》2010,397(8):3249-3267
Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently,
there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored
to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic
techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted
to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques,
detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application.
Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics
were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies
and suggest directions which may make them more accessible. 相似文献
86.
87.
Component based software development (CBSD) is well acknowledged as a methodology which establishes reusability of software and reduce development cost effectively. While developing enterprise application using component based software engineering (CBSE) methods, software component selection plays a very important role in the process of component retrieval, adaptation and assembly. However, most of current researches focus on technical aspects from domain engineering and application engineering to improve reusability and system efficiency rather than application of optimization methods in CBSD management, especially application in component selection. Moreover, few existing researches have concerned about the situation where a software developer or enterprise develops multi-applications at the same time. By introducing the concept of reusability and a new formulation of compatibility matrix, an optimization model is proposed to solve component selection problem considering reusability and compatibility simultaneously. The model can be used to assist software developers in selecting software components when multi-applications are undertaken concurrently. Four experiments are conducted with the purpose to provide some insights in management perspective. 相似文献
88.
2,4-Bis(3,5-dimethylpyrazol-1-yl)-6-methoxyl-1,3,5-triazine(bpt) has been synthesized by using a new, simple and general method with high yields. Reactions of bpt with Ni(CIO4)2 · 6H2O and Zn(CIO4)2 · 6H2O in methanol gave mononuclear complex [Ni(bpt)2] · (CIO4)2 · H2O and ternary complex [Zn(mpt)2(dmp)](CIO4)2 respectively, where mpt (2,4-dimethoxy-6-(3,5-dimethyl-pyrazol-1-yl)-1,3,5-triazine) and dmp(3,5-dimethylpyrazole) are the alcoholysis products of bpt in the presence of Zn2+ ion. A possible mechanism for this catalytic reaction was proposed. X-ray crystal structure for ligand bpt, Ni and Zn complexes are reported. The protonated form of the ligand bpt crystallizes as its perchlorate salt including one molecule of water, [Hbpt · H2O · CIO4]. The proton is located on one pyrazole N-atom. [Hbpt ?H2O ?CIO4], in which [Hbpt]+ is in cis-cis conformation, are packed in slipped stacks of approximately parallel layers. The π-π overlap interactions between the non-protonized pyrazoles of the adjace 相似文献
89.
Czechoslovak Mathematical Journal - Let $$T(q) = \sum\limits_{k = 1}^\infty {d(k){q^k},\,\,\,\,\left| q \right| < 1,} $$ where d(k) denotes the number of positive divisors of the natural... 相似文献
90.