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41.
A ghost interface simulation technique is developed and applied to supersaturated Lennard-Jones liquid-vapor interfaces. It is shown that the surface tension decreases approximately linearly with the supersaturation ratio and that it vanishes at the spinodal. The effect leads to a curvature-dependent surface tension since, it is argued, the local supersaturation of the vapor above a droplet is greater than in the bulk due to slow diffusion in the vapor phase. An analytic approximation is given for the local supersaturation ratio, and an analytic expression for this contribution to Tolman's length is derived. The theory gives a smaller critical radius and reduces the free energy barrier to nucleation compared to classical homogeneous nucleation theory, which have important implications for the kinetics of droplet and bubble formation. 相似文献
42.
A synthesis of a previously unknown indole derivative is presented. The route reported herein allows for the preparation of multihundred gram quantities of material without any chromatographic purification. Conditions are presented for the Pd-catalyzed elaboration of one of the "diversity generating elements" of this important pharmacophore. 相似文献
43.
A simple colorimetric technique is implemented in a polymer microfluidic manifold. The simple chemistry aids an uncomplicated microchannel design, which is fabricated by CO(2) laser ablation. Issues such as bonding of multiple layers, alignment of micro-fabricated structures and integration of optical components are addressed. A demonstration of a stopped flow regime in the microfluidic manifold is also presented. 相似文献
44.
N. S. Kelsall C. E. Svensson S. Fischer D. E. Appelbe R. A. E. Austin D. P. Balamuth G. C. Ball J. A. Cameron M. P. Carpenter R. M. Clark M. Cromaz M. A. Deleplanque R. M. Diamond P. Fallon D. F. Hodgson R. V. F. Janssens D. G. Jenkins G. J. Lane C. J. Lister A. O. Macchiavelli C. D. O’Leary D. G. Sarantities F. S. Stephens D. C. Schmidt D. Seweryniak K. Vetter J. C. Waddington R. Wadsworth D. Ward A. N. Wilson A. V. Afanasjev S. Frauendorf I. Ragnarsson 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):131-132
High-spin states have been studied in 72Kr and 72Br using the 40Ca + 40Ca and 36Ar + 40Ca reactions at 164 and 145 MeV, respectively. The properties and configurations of the high-spin bands observed have been interpreted using unpaired cranked Nilsson-Strutinsky (CNS), and for 72Kr, paired cranked relativistic Hartree-Bogoliubov (CRHB) calculations. In 72Kr a new band has been identified that has the properties expected for the doubly aligned S-band configuration. In 72Br the previously known bands have been extended to higher spin. This has lead to a re-interpretation of the configurations.Received: 31 October 2002, Published online: 24 February 2004PACS:
21.10.Re Collective levels - 23.20.Lv
transitions and level energies - 27.50. + e
相似文献
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A surface plasmon resonance (SPR) sensing system based on the optical cavity enhanced detection tech-nique is experimentally demonstrated. A fiber-optic laser cavity is built with a SPR sensor inside. By measuring the laser output power when the cavity is biased near the threshold point, the sensitivity, defined as the dependence of the output optical intensity on the sample variations, can be increased by about one order of magnitude compared to that of the SPR sensor alone under the intensity interrogation scheme. This could facilitate ultra-high sensitivity SPR biosensing applications. Further system miniaturization is possible by using integrated optical components and waveguide SPR sensors. 相似文献
47.
Solar panels and bio‐optical sensors play a significant and growing role in a number of applications that are of importance to many organizations. Many of these instruments require a high transmission of radiation into the device for it to work properly. A major issue faced is that harsh marine environments often aid in the growth or development of fouling on the coverglass used to protect the instruments. Over a period of time in an ocean environment, some plant or animal may attach itself to the coverglass, ultimately obscuring the glass and rendering the instrument useless. As such, an antifouling mechanism is needed for these instruments that is inexpensive, long‐lasting, and environment friendly. The approach discussed herein involves the use of known antifouling chemicals which have been incorporated into the polymer matrix. Polymethylmethacrylate (PMMA), bisphenol A polycarbonate (Bis A PC), and a co‐polyterephthalate (CPTE) were examined. The plaques are optically transparent and previous work has shown that, for most samples, the materials display a minimal decrease in mechanical behavior upon the addition of the algaecides. This paper will discuss the effects on the materials' optical properties when exposed to both harsh marine conditions as well as high intensity UV light. Specifically, the decrease in transmission of visible light was examined over a 6 month period of time. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The thioether functionalized aminosilanes Me2Si(NH‐C6H4‐2‐SR)2 (R = Ph, Me) were lithiated with nBuLi and subsequently reacted with AgCl in the presence of PMe3 or with [AuCl(PMe3)]. In the case of Me2Si(NH‐C6H4‐2‐SPh)2 the dinuclear complexes [M2{Me2Si(NC6H4‐2‐SPh)2}(PMe3)2] (M = Ag; Au) were isolated. The analogous reactions starting from Me2Si(NH‐C6H4‐SMe)2 afforded the dinuclear gold complex [Au2{Me2Si(NC6H4‐2‐SMe)2}(PMe3)2] and the tetranuclear silver complex [Ag4{Me2Si(NC6H4‐2‐SMe)2}2(PMe3)2]. In the dinuclear compounds of the type [M2{Me2Si(NC6H4‐2‐SR)2}(PMe3)2], each of the silylamide N atoms is connected to a M(PMe3) group to give a nearly linear N–M–P arrangement with Ag–N and Au–N bonds in the range of 212.0(4)–213.3(4) pm and 205.3(3)–208.1(9) pm, respectively. [Ag4{Me2Si(NC6H4‐2‐SMe)2}2(PMe3)2] consists of a central Si2N4Ag2 ring with linearly coordinated Ag atoms (Ag‐N: 223.1(4)–222.1(4) pm) and two peripheral Ag(PMe3) units, which are connected to the amido N atoms in a chelating mode. The relatively short transannular Ag ··· Ag separation (277.6(1) pm) within the Si2N4Ag2 ring hints for argentophilic interactions. The peripheral Ag atoms are three coordinated with Ag–N distances of 233.9(4)–242.8(4) pm. 相似文献