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81.
We have measured the concentration dependence of the average magnetic moment per Fe atom Fe(x) in microcrystalline and amorphous Fe-P alloys obtained over a wide concentration range using electrochemical deposition. The model of local magnetic moments has been used to described Fe(x). On the basis of this model the effects of phosphorus on the value Fe are explained in terms of the parameters of the local environment of the Fe atom.  相似文献   
82.
83.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 994–996, July, 1992.  相似文献   
84.
Advantage of use residue from thermal cracking and products of its condensation as components of the mixture for manufacturing mechanically rigid (93%) granulated and ground carbon sorbents with extended volume of micropores (up to 0.27 cm3/cm3), showing enhanced sorption activity (E is up to 25.6 kJ mol?1) and high ability of separation various gas mixtures is demonstrated. As a carrier for medicine preparations these adsorbents show higher performance as compared with industrial samples. Solutions of the cracking residue can be used for impregnation of worked out zeolites for petroleum technology and for production of organomineral adsorbents with high adsorption capacity on extraction mercury from sewages.  相似文献   
85.
The capillary pressure in a liquid interlayer between two spherical particles is calculated as a function of their sizes and the wetting properties of the liquid.  相似文献   
86.
The crystallization behavior of miscible syndiotactic polystyrene (sPS) and atactic polystyrene (aPS) blends with different sPS/aPS weight ratios was investigated in supercritical CO2 by using Fourier‐transform infrared spectroscopy, differential scanning calorimetry, and wide‐angle X‐ray diffraction. Supercritical CO2 and aPS exhibited different effects on the conformational change of sPS and competed with each other. Increasing the content of amorphous aPS in the blends made its effect on the conformational change of sPS gradually surpass that of supercritical CO2. Supercritical CO2 favored the formation of the helical conformation of sPS in lower temperature range and the all trans planar conformation in higher temperature range, instead of forming the latter one only in higher temperature range in ambient atmosphere. However, increasing aPS content in the blends pushed the range for forming the helical conformation to lower temperature and made the all trans planar conformation dominant in aPS/sPS 25/75 blend after treating in supercritical CO2 above 60 °C. The all trans planar zigzag conformation was more favorable than the helical conformation after mixing aPS in sPS in supercritical CO2. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1755–1764, 2007  相似文献   
87.
A combination of nitroxide‐mediated radical polymerization and living anionic polymerization was used to synthesize a series of well‐defined graft (co)polymers with “V‐shaped” and “Y‐shaped” branches. The polymer main chain is a copolymer of styrene and p‐chloromethylstyrene (PS‐co‐PCMS) prepared via nitroxide‐mediated radical polymerization. The V‐shaped branches were prepared through coupling reaction of polystyrene macromonomer, carrying 1,1‐diphenylethylene terminus, with polystyryllithium or polyisoprenyllithium. The Y‐shaped branches were prepared throughfurther polymerization initiated by the V‐shaped anions. The obtained branches, carrying a living anion at the middle (V‐shaped) or at the end of the third segment (Y‐shaped), were coupled in situ with pendent benzyl chloride of PS‐co‐PCMS to form the target graft (co)polymers. The purified graft (co)polymers were analyzed by size exclusion chromatography equipped with a multiangle light scattering detector and a viscometer. The result shows that the viscosities and radii of gyration of the branched polymers are remarkably smaller than those of linear polystyrene. In addition, V‐shaped product adopts a more compact conformation in dilute solution than the Y‐shaped analogy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4013–4025, 2007  相似文献   
88.
The absorption and circular dichroism spectra of langasite family crystals are studied. Wide bands in the range of 285–500 nm that are related to the structure lattice defects are found. For all the crystals, these bands are in approximately the same spectral region, have identical structures, and can be attributed to one type of defects formed by cation vacancies and excess oxygen atoms in the optically active positions.  相似文献   
89.
90.
A new co‐ordinate invariant streamwise upwind formulation for convection dominated flows is developed. The eddy diffusivity/viscosity is added directly to the equations in order to remove the oscillations in the solution. The equations then can be solved by any high‐order scheme and the solution retains the accuracy of the high‐order scheme. The accuracy and reduced lateral thickness growth rate are demonstrated with several numerical examples, including pure convective flows and lid‐driven cavity flow. The lateral spreading due to the numerical diffusion is controlled by the anisotropic tensor. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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