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31.
By the example of the lowest resonance state of the H? system, two versions of the stabilization method are considered: with introduction of an external potential into the Hamiltonian and with enlargement of the single-particle function basis. A comparison of the results suggests the possibility of applying these methods to calculating the resonance parameters in many-electron systems.  相似文献   
32.
Journal of Solid State Electrochemistry - Potassium metal anode solid-state cells with a K-beta”-alumina ceramic electrolyte are found to have relatively high critical currents for dendrite...  相似文献   
33.
Replacing the Pro6 in the p6(Gag)-derived 9-mer "P-E-P-T-A-P-P-E-E" with N-substituted glycine (NSG) residues is problematic. However, incorporation of hydrazone amides ("peptoid hydrazones") can be readily achieved in library fashion. Furthermore, reduction of these hydrazones to N-substituted "peptoid hydrazides" affords a facile route to library diversification. This approach is demonstrated by application to Tsg101-binding compounds designed as potential HIV budding antagonists. [reaction: see text]  相似文献   
34.
Functionalized single graphene sheets derived from splitting graphite oxide   总被引:17,自引:0,他引:17  
A process is described to produce single sheets of functionalized graphene through thermal exfoliation of graphite oxide. The process yields a wrinkled sheet structure resulting from reaction sites involved in oxidation and reduction processes. The topological features of single sheets, as measured by atomic force microscopy, closely match predictions of first-principles atomistic modeling. Although graphite oxide is an insulator, functionalized graphene produced by this method is electrically conducting.  相似文献   
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In this article a solvent injection method is described for vesicle formation using poly(butadiene)‐ b‐poly(acrylic acid) diblock copolymers as the amphiphilic molecules. Vesicles composed of polymer bilayers are commonly referred to as polymersomes. Solvent injection is shown to be a rapid method for polymersome formation suitable to make large volumes of polymersome solution. The method can be manipulated to obtain a wide range of vesicle sizes depending on the polymer concentration and preparation conditions. Polymersome solutions in this study are characterized using dynamic light scattering (DLS), fluorescent microscopy, and electron microscopy. Polymersome sizes range from tens of nanometers to several microns. The membrane thickness of smaller polymersomes is found to lie between 14–20 nm. Larger polymersomes are found to have somewhat thicker membranes. The procedure involves the addition of polymers dissolved in an organic solvent to a stirred aqueous solution. The formation of polymersomes by this method is proposed to be governed by the limited mutual solubility of the two solvents and the simultaneous diffusion of solvent and water out of and in to initially formed organic solvent droplets. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
37.
The deoxyfluoro-D-glucopyranoses with the fluorine substituent severally at positions 6, 4, 3 and 2 were converted into the corresponding deoxyfluoro-D-glucitol pentaacetates (I to IV) and their 1-deuterated analogues (V to VIII). The mass spectra of these derivatives were rationalised in terms of the position of the fluorine substituent on the carbon chain.  相似文献   
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Physics Institute, Estonian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 33, No. 8, pp. 970–975, August, 1990.  相似文献   
40.
The diffraction broadening of the high-aperture freely propagating (vector) Bessel and Gaussian beams is considered. The dependences of the degree of transverse concentration of light in such beams on their axial and radial coordinates are obtained. It is shown that if the initial degree of the transverse localization of total power of these beams is the same, the diffraction broadening of a Gaussian beam is smaller than that of a Bessel beam, and the only advantage of the latter is the specific radial distribution of the field amplitude.  相似文献   
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