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排序方式: 共有227条查询结果,搜索用时 15 毫秒
71.
Sarit Maitra Rajkumar Roychoudhury Kalyan Kr. Mondal 《Czechoslovak Journal of Physics》2005,55(8):943-955
The effect of higher-order nonlinearity on dust acoustic solitary waves is studied taking into account the dust-charge variation.
The model of charge fluctuation, taken here, is of the formI
e+I
i=0,I
e andI
i being the electronic and ionic currents. The dust charge is determined self consistently from the current-balance equation.
It is found that the higher-order correction modifies the amplitude and width of the dust acoustic solitary waves. The effect
of dust-charge streaming is also discussed. 相似文献
72.
[structure: see text] A novel cholaphane has been synthesized from a naturally occurring bile acid in just two steps. It has an ability to bind two fluoride ions selectively utilizing the glycolate motif in chloroform. This "inside-out" cyclodextrin analogue encapsulates fluoride through O-H...F(-) and C-H...F(-) interaction. 相似文献
73.
74.
A series of deoxycholic and cholic acid‐derived oligomers were synthesized and their ability to extract hydrophilic dye molecules of different structure, size, and functional groups into nonpolar media was studied. The structure of the dye and “dendritic effect” in the extraction process was examined using absorption spectroscopy and dynamic light scattering (DLS). The efficiency of structurally preorganized oligomers in the aggregation process was evaluated by 1‐anilinonaphthalene‐8‐sulfonic acid (ANS) fluorescence studies. The possible formation of globular structures for higher‐generation molecules was investigated by molecular modeling studies and the results were correlated with the anomaly observed in the extraction process with this molecule. The ability of these molecules for selective extraction of specific dyes from blended colors is also reported. 相似文献
75.
Arpita Ghosh Somenath Chakrabarty 《The European Physical Journal A - Hadrons and Nuclei》2011,47(4):56
We have studied various physical properties of magnetically deformed atoms and the associated matter, replacing the atoms
by the deformed Wigner-Seitz (WS) cells at the crustal region of strongly magnetized neutron stars (magnetars). A relativistic
version of the Thomas-Fermi (TF) model in the presence of a strong magnetic field in cylindrical coordinates is used to study
the properties of such matter. 相似文献
76.
Debromination of vicinal‐dibromides to E‐alkenes is reported using inorganic solid supports (silica gel or acidic alumina) under microwave irradiation. 相似文献
77.
The interaction between styrene-butadiene rubber (SBR) film and the ions from C2S and C3S hydration of Portland cement mortar composites has been evaluated by Fourier Transform Infrared Spectroscopy (FTIR), and the morphology of the composites characterized with scanning electron microscopy (SEM). The specimen used was cured for 28 days. FTIR spectrum supports the interaction of SBR with cement in the composite. Compressive strength, bulk density and water absorption properties of the cured composites were tested. Addition of SBR latex in Portland cement mortar increases the compressive strength and decreases the water absorption. Bulk density study revels interface formation in the composite. The role of the interface in relation to compressive strength of the composite has been discussed. A simple Matrix System model is shown to account composition dependence of bulk density. 相似文献
78.
Two efficient and green methods for synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) without use of any catalyst or solvent have been developed simply by heating (at 120°C) or microwave irradiation (300 W) of intimate mixtures of 3-methyl-l-phenyl-5-pyrazolone and aldehyde in 2:1 mole ratio. 相似文献
79.
Summary A study is presented of the thermoanalytical and gas chromatographic (GC) properties of the copper(II) complexes of twenty four tetradenate Schiff's bases. Variations in thermal stability, volatility and GC retention of the complexes are discussed in terms of stereo-electronic effects of the substituents. Although some complexes decomposed extensively during vaporization above 250°C all, apparently, survive chromatography intact at 200°C. Certain complexes were separated as distinct regio-isomers by GC. Fluorinated ligands still appear to be the most suitable derivatizing reagents for Cu(II). 相似文献
80.
P. K. Das Prasanta Haldar Arpita Chatterjee 《International Journal of Theoretical Physics》2016,55(11):4951-4962
We discuss nonclassicality of a superposition of coherent states in terms of sub-Poissonian photon statistics as well as the negativity of the Wigner function. We derive an analytic expression for the Wigner function from which we find that the function has some negative region in phase space. We obtain a compact form of the Wigner function when decoherence occurs and study the effect of decoherence on the state. We demonstrate the behaviour of the nonclassicality indicator. 相似文献