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The crystal structure of the metal-organic frame Ca(C5H9O5)2·CH3OH·2H2O(1) has been synthesized and characterized.Complex 1 belongs to a tetragonal P43212 space group.In complex 1,the sugar moiety shows a beta-L configuration of pyranose form.The calcium(Ⅱ) is eight-coordinated,binding to four such sugar moieties,via O(1),O(2) of two molecules and O(3),O(4) of the other two,with the 4-hydroxy group being deprotonated.The water and methanol molecules are not coordinated to the calcium ion. 相似文献
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Inside Back Cover: On the Resolution Limit of Femtosecond Stimulated Raman Spectroscopy: Modelling Fifth‐Order Signals with Overlapping Pulses (ChemPhysChem 16/2015) 下载免费PDF全文
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Triphenylphosphine-mediated metal-free trifluoromethylthiolation and difluoromethylthiolation of thiols by CF3SO2Cl and CHF2SO2Cl to synthesize trifluoromethyl disulfides and difluoromethyl disulfides, respectively, was achieved at room temperature. Iodine generated in situ from iodide facilitated this reaction via the formation of iodotriphenylphosphonium iodide which could serve as a reducing agent in this transformation. Readily available reagents and mild reaction conditions without transition-metals allow this protocol to be more practical than traditional methods. 相似文献
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Transition Metal Chemistry - A Cu(II) coordination polymer, [Cu2(pztrz)2(μ-CH3COO)(CH3COO)]·3H2O (1), derived from mono-substituted 1,2,4-triazole derivative 3-(pyrazinyl)-1,2,4-triazole... 相似文献
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We consider the integral functional
under non-standard growth assumptions that we call p(x) type: namely, we assume that
a relevant model case being the functional
Under sharp assumptions on the continuous function p(x)>1 we prove regularity of minimizers. Energies exhibiting this growth appear in several models from mathematical physics.
Accepted July 13, 2000?Published online January 22, 2001 相似文献
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OBJECTIVES: To inform on Teratology Information Services (TIS) in Europe, their history, function and activity in preventing congenital malformations. CONCLUSIONS: Clinical teratology tries to identify human teratogens. TIS play an important role in public health by providing counsel on known reproductive risks and conducting specific research. This has led to a reduction in unnecessary fears of pregnant women and pregnancy terminations, as well as to better, more appropriate drug selection to treat acute or chronic disease. In addition, TIS units also conduct prospective studies and inform the public and physicians of the possible effects of environmental agents on the developing embryo and fetus. 相似文献