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861.
I. V. K. Bhagavan Raju 《Crystal Research and Technology》1983,18(5):687-693
Precipitation morphology of NaCl:CdCl2 and NaCl:SrCl2 crystals is investigated by high voltage transmission electron microscopy. The volume fraction of the precipitates and the content of CdCl2 has been evaluated using the theory developed by Hillard. Selected area diffraction patterns of the precipitates and investigations of the misfit dislocations around the precipitates is presented. 相似文献
862.
863.
Spiroketals are widely found as substructures of many naturally occurring compounds from diverse sources including plants, animals as well as microbes. Naturally occurring spiroketals are biologically active and most of them are chiral molecules. This article aims at reviewing the asymmetric synthesis of biologically active spiroketals for last 10 years (1998-2007). 相似文献
864.
A cross-coupling reaction of a variety of aryl, heteroaryl, and benzyl chlorides with ArMgX is catalyzed by 2 mol % of a nickel-phosphine complex prepared in situ from an equimolar amount of Ni(CH(3)CN)(2)Cl(2) and ligand (L2) to yield products in excellent yield in THF at room temperature. This new bidentate ligand (L2) is stable in air and forms a stable complex upon reaction with Ni(CH(3)CN)(2)Cl(2). Structures of the ligand and the complex were confirmed by single-crystal X-ray diffraction. 相似文献
865.
Synthesis of several 5,5‐dimethyl‐2‐oxido‐[1,3,2]‐dioxaphosphorinane‐2‐yl‐amino carboxylates ( 4a–j ) was accomplished through a two‐step process. This involves prior preparation of the intermediate monochloride ( 2 ), 2‐chloro‐5,5‐dimethyl [1,3,2]dioxaphosphorinane‐2‐oxide and its subsequent reaction with various amino acid esters ( 3a–j ) in dry tetrahydrofuran in the presence of triethyl amine at room temperature. They were characterized by elemental analysis, IR, 1H, 13C, 31P NMR, and mass spectral data. Their antifungal and antibacterial activity is also evaluated. Majority of these compounds exhibited moderate antimicrobial activity in the assay. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:256–260, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20426 相似文献
866.
Iso-epitaxial(epilayer)growth of n-octacosane crystals is reported. The morphology of the epilayers is in the form of triangular growth islands with or without truncature. Epilayer growth precedes spiral growth mechanism which occurs at medium and low supersaturations, respectively. The occurrence of triangular and truncated rhombic platelets is found to be a manifestation of growth at medium supersaturations. 相似文献
867.
Modifications in spiral step patterns on n-octosane crystals resulting from stress fields is considered. Stress field seems to impede the propagation of growth fronts across it and leads to the formation of bunched step patterns. Effect of cylindrical stress fields with axes parallel and perpendicular to the direction of step motion is considered in altering the shapes of the bunched steps. Shear modulus of n-octacosane crystals is estimated from the microtopographical features. 相似文献