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61.
In this paper, the electronic transport of La(0.7)(Sr,Ca)(0.3)MnO(3) films grown by pulsed laser deposition on a LaAlO(3)(001) substrate with deep parallel structured steps and a 30° symmetric bicrystal SrTiO(3)(001) substrate have been discussed. The electronic transport properties have been related to the well-known extrinsic transport of bulk manganite compounds. The spin-glass-like behavior with a characteristic peak at 20 K and domain formation at the grain boundary is observed. Further, it has been quantified from the resonant tunneling model that mixed magnetic interactions play a significant role in the manganite films deposited on step edges.  相似文献   
62.
The reaction of the palladium nitrate trans-[Pd(NO3)2(H2O)2] with acetylacetone affords mononuclear [Pd(acac)2] (acac = acetylacetonate), mixed-ligand binuclear [Pd2(acac)3NO3] (1) and polynuclear [Pd(acac)NO3]n (2) complexes depending on the Pd:acetylacetone ratio in the reaction mixture. The binuclear 1 and insoluble polynuclear 2 were isolated and studied by single-crystal X-ray diffraction (1) and solid-state 13C MAS NMR (1 and 2). It was found that in both compounds the Pd ions are linked together through bridging acetylacetonate ligands where one metal atom is connected to the usual O,O-donor sites, whereas the other metal atom forms a bond with the γ-carbon center. Based on a topological quantum-chemical method, the Pd-γ-C bond was classified as a strained dative bond.  相似文献   
63.
A procedure was developed for synthesizing nitrogen-and-sulfur-containing pyrimidine derivatives by reactions of 1,3-bis(3-chloro-2-hydroxypropyl)-6-methyluracil with 1-butanethiol and chloroacetyl chloride, followed by treatment of the resulting 1,3-bis[3-chloro-2-(chloroacetoxy)propyl]-6-methyl-1,2,3,4-tetrahydropyrimidine-2,4-dione with 1-butanethiol, morpholine, and piperidine. Oxidation of the sulfur-containing products with NaIO4 gave the corresponding sulfoxides.  相似文献   
64.
A procedure was developed for the quantitative determination of olefin oxide, chlorohydrin, and cyclocarbonate simultaneously present in the reaction mixture of the synthesis of cyclocarbonate from olefin oxide and CO2. To determine olefin oxide, an acetone solution of hydrochloric acid was added to a portion of the reaction mixture, and the excess of hydrochloric acid was titrated with an aqueous solution of potassium hydroxide with visual detection. The concentrations of chlorohydrin and cyclocarbonate were calculated from the data of the potentiometric titration of the same solution to which excess potassium hydroxide was added. Deceased.  相似文献   
65.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.  相似文献   
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Russian Journal of Physical Chemistry A - A catalyst containing chromium oxide particles on the surface of palladium nanoparticles is synthesized for the first time using a redox technique for...  相似文献   
69.
In reaction of trifluormethyl-containing 1,3-diketones with oxalyl chloride 5-substituted 4-(trifluoracetyl)furan-2,3-diones were synthesized, reaction of which with azomethines resulted in 4-substituted 5-hydroxy-5-(trifluormethyl)dihydrofuran-2,3-diones.  相似文献   
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