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901.
Two novel dithienylethenes with ferrocene units were synthesized by Wittig reaction. The structure of 2a has been established by X‐ray diffraction studies. They could reversibly interconvert between two thermally stable forms, an open and a closed one, using light of different wavelengths as triggers. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
902.
The magnetic and magnetoelastic parameters of Fe64Co21B15 and Fe81.5B13.5Si3C2 amorphous ferromagnetic alloys treated by direct electric current in air are studied as functions of the applied magnetic field and current density. The samples of the alloy have the form of narrow strips with different lengths. It is found that the magnetoelastic parameters of the dc-treated alloys depend on the magnetic field in a qualitatively different way. From the behavior of the magnetic and magnetoelastic parameters of the alloys in the magnetic field a model of magnetization nonuniform distribution in amorphous ferromagnetic alloys subjected to dc treatment is proposed.  相似文献   
903.
A direct (without sample pretreatment) atomic-absorption method of V and Ni determination in oil with electrothermal atomization and Zeeman correction of background was developed.  相似文献   
904.
The possibility of raising the static exchange capacity of strongly acidic ion-exchange materials produced by grafting of styrene onto polypropylene fibers, with the subsequent sulfonation of the products synthesized, was analyzed. The chemical and osmotic stabilities of the sulfonic cation exchangers obtained and their frost resistance in freeze-thaw cycles were studied.  相似文献   
905.
Conformationally heterogeneous 2-substituted 1,3-dithiacyclohept-5-enes (R = Ph, Me, t-Bu), which exist in solution as chair and boat conformers, react with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate with high exo-diastereoselectivity: only the chair conformer is involved. The steric structure of 4-methyl-3,5-dithia-9,10-diazabicyclo[5.4.0]undeca-7,10-diene was determined by X-ray analysis. Its crystal packing and supramolecular structure were also analyzed.  相似文献   
906.
Dioxirane generated in situ by reaction of chiral 1,2:4,5-di-O-isopropylidene-D-erythro-hexo-2,4-diulo-2,6-pyranose with Oxone oxidizes prochiral sulfides to the corresponding sulfoxides with an enantiomeric excess of 2 to 25%.  相似文献   
907.
The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements.  相似文献   
908.
Retraction: The following article from Biomedical Chromatography, “Determination of scutellarin isomer, a predominant metabolite of scutellarin, in human plasma by HPLC/tandem mass spectrometry and its application to the pharmacokinetic study in Chinese healthy volunteers” by Chun‐hua Xia, Yu‐qing Xiong, and Guang‐ji Wang, published online on 21 June 2007 in Wiley Interscience (www.interscience.wiley.com/journal/bmc), has been retracted at the authors' request.  相似文献   
909.
910.
横向光泵获得S_2紫外激光   总被引:1,自引:1,他引:0  
用XeCl准分于激光器(308.1nm)横向泵浦S2激光器,又成功地实现了S2B-X态近UV波段的激光振荡。在波长330.9~390.0nm范围内观测到6条近UV激光输出。测量了有关的激光参数。  相似文献   
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