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31.
32.
四核钴羰基簇合物Co4(CO)8(μ-CO)2(μ4-PSR)2的合成和晶体结构 总被引:1,自引:0,他引:1
The title compounds Co4(CO)8(μ-CO)2 (μ4-PSR) [R=-CH3, -C2H5, -C(CH3)3,-(CHa)4CH3] were synthesized by the reaction of Co2(CO)8 with RSPCl2. They were characterized by IR, 1HNMR, elemental analysis. The crystal and molecular structure of Co4(Co)8(μ-CO)2 (μ4-PSC2H5) has been determined by single crystal diffraction method. Crystal data: monoclinic, space group P21 /c, with a=8-445(3), 6=8.562(3), c= 17.125(6)Å, β=104.26 (3)' 9 V=1200.1Å3, Z=2, Dc=1.937gcm-3. Its molecular structure contains an octahedral Co4P2 skeleton which consists of a rectangular four cobalt atoms core and the Co4 core is capped above and below by two quadruply bridging PSR ligands. 相似文献
33.
Kenji Miyatake Mitsutoshi Jikei Junya Katoh Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1994,5(4):216-220
Poly(2,5-dimethylphenylene sulfide) was prepared by oxidative polymerization of sulfur chloride with p-xylene using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) as an oxidizing agent. The reaction proceeded efficiently under atmospheric pressure and at room temperature. The polymer formed had a high melting temperature and linear structure which was confirmed by spectroscopies. The effects of reaction time, solvent, temperature and oxidizing agent on polymerization are also discussed. 相似文献
34.
Semiconductor–semiconductor and molecule (molecular ion)–semiconductor products are formed upon the implantation of Ag+, Cu+, and Cu2+ ions in the CdS surface. Possible mechanisms were examined for their photocatalytic action in the reduction of methylene blue. 相似文献
35.
Synthesis and Crystal Structure of a Novel Hexagonal Modification of Al2S3 with Five-coordinated Aluminum A new hexagonal high temperature modification of Al2S3 could be prepared by chemical vapour transport with iodine (860 → 750°C) or by annealing of α -Al2S3 at 550°C. According to the single crystal X-ray structure determination the novel form of Al2S3 crystallizes in space group P 61 (No. 169) with a = 6.491(1), c = 17.169(4) Å, V = 626.5 Å3, Z = 6; R = 0.0253. In this modification one half of the aluminum atoms are tetrahedrally coordinated [d(Al? S): 2.226–2.267 Å], whereas the other half are in trigonal bipyramidal coordination of five S atoms with bond lengths of 2.272–2.315 Å (equatorial) and 2.495–2.521 Å (axial). Aluminum in AlS5 coordination is observed for the first time in this compound. The crystal structure is isotypic to In2Se3 and AlInS3. In addition, results of a refinement of the α -Al2S3 crystal structure are reported which were obtained on crystals prepared also by chemical vapour transport with iodine. 相似文献
36.
《中国化学快报》2020,31(6):1535-1539
Chlorinated organic pollutants(COPs) have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized the bimetallic iron-nickel sulfide(FeNiS) particles which exhibited excellent catalytic property of COPs removal.FeNiS was chosen as the peroxydisulfate(PDS) activator to removal COPs including 4-chlorophenol(4-CP),1,4-dichlorophenol(1,4-DCP) and 2,4,6-trichlorophenol(2,4,6-TCP).The results show that FeNiS can efficiently activate PDS to produce sulfate radical(SO_4~(·-)) which plays major role in the oxidative dechlorination and degradation due to its strong oxidizing property and the ability of producing hydroxyl radicals(~·OH) in the alkaline condition.Meanwhile,the Cl-abscised from COPs during the dechlorination can turn into the chlorine radicals and enhance the degradation and cause further mineralization of intermediate products.This bimetallic FeNiS catalyst is a promising PDS activator for removal of chlorinated organics. 相似文献
37.
Catherine J. Murphy 《Journal of Cluster Science》1996,7(3):341-350
One of the most exciting frontiers in materials chemistry in recent years is the optoelectronics of quantum-confined semiconductor nanoclusters. These nanoclusters are 10–200 A in diameter, and in this size regime exhibit extra-ordinarily interesting quantum mechanical effects. Cadmium sulfide is a popular semiconductor for these studies, and reviewed here is the synthesis and charac-terization of such CdS nanoclusters, with emphasis on how chemical control of the surface by thiolates influences product formation and properties. Also described are the syntheses and structures of true molecular clusters of CdS capped with thiolate ligands. 相似文献
38.
William H. Donovan 《Structural chemistry》1995,6(4-5):243-254
Ab initio and semiempirical molecular orbital calculations have been applied to study the concerted and stepwise isotopic scrambling mechanisms of 2-chloroethyl methyl sulfide in the gas phase and in aqueous solution. The calculations reveal the structural details of the reactants, transition structures, and intermediates involved in this reaction and provide relative energy estimates. The concerted mechanism is found to be competitive with the stepwise mechanism in the gas phase, but the stepwise mechanism is favored in aqueous solution as no true transition structure for the concerted mechanism could be found using the solvation models. A combined approach of evaluating solvation energies with the generalized-Bom-plus-surface-tensions SM
x
solvation models of Cramer and Truhlar at ab initio optimized geometries is found to deliver the best agreement with experimentally determined reaction barriers. Together with the recent experimental results of McManus and co-workers, the present study provides insights into the controlling factors involved in the elementary reaction steps of sulfur mustards and a solid foundation for investigations into more complex reactions of related compounds. 相似文献
39.
Shin-ichi OhsugiKiyoharu Nishide Keiji OonoKazunori Okuyama Masato FudesakaSumiaki Kodama Manabu Node 《Tetrahedron》2003,59(42):8393-8398
Development of the odorless dodecyl methyl sulfide (Dod-S-Me, 1) as an alternative for dimethyl sulfide (DMS) and new odorless methods for the Corey-Kim and Swern oxidations are described. These reactions have been developed with a view toward green chemistry, utilizing Dod-S-Me (1) and common solvents instead of dichloromethane. 相似文献
40.
The purpose of this research was to select an activated carbon and alkaline solution blend that generated the best H2S adsorption on alkaline-activated carbon. RB2 (activated carbon) impregnated with NaOH solution was shown to have the optimum H2S removal efficiency. The optimum NaOH concentration was 50 mg per gram of carbon. H2S adsorption via RB2-NaOH50 was five times that of a corresponding fresh-activated carbon. The adsorption equivalent of H2S is nearly 1 (mol-H2S/mol-AOH), therefore, H2S + AOH AHS + H2O was the major reaction. The H2S adsorption isotherm corresponded to the Freundlich isotherm. 相似文献