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971.
本文报道了一种以2,3,9,10-四甲基-1,4,8,11-四氮杂环十四-1,3,8,10-四烯镍(Ⅱ)配合物[Ni(ㄔIM)]^2+为催化剂、NaBrO3为氧化剂、丙酮酸为有机废物、稀硫酸为介质的振荡化学反应新体系。对该体系的振荡特性进行了描述。研究了Ag^+、Hg^2+、还原性物质、自由基抑制剂、四氯化碳以及温度对振荡的影响。  相似文献   
972.
Pentacoordinate complex cations of the general formula [(C6F5)2SbL3]3+ stabilized as solid salts in combination with tetraphenylborate (BPh4), tetrafluorobroate (BF4) anions, where L=DMSO, Ph3AsO, PyO, DMF, α-, β- and γ-picoline have been isolated. The newly formed complexes were characterized by elemental analysis, molar conductance measurements, solid-state IR and and NMR. From these results, a five-fold coordination around antimony was required.  相似文献   
973.
As a second-generation pyridoxal model compound for cystathionine β-synthase, we designed a novel model compound having an ionophore function and an imidazole function, application of which to the β-replacement reaction with various thiols smoothly took place to give S-substituted cysteines. Peptides having a serine-O-carbonate residue at the N-terminal position were also converted to the corresponding peptides having an S-substituted cysteine residue under the catalytic conditions of the novel pyridoxal model compound.  相似文献   
974.
The UV photolysis of 2′-chloro-4-R-benzanilides in acetonitrile solution under nitrogen atmosphere leads to the formation of intramolecular photocyclization products (9-R-phenanthridin-6(5)-one, 20–30%), along with the minor photoreduction, photo-Fries, and intramolecular photosubstitution products. The photoreaction of 2′-chloro-4-R-benzanilide in acetonitrile solution containing 10% of water or aqueous sodium hydroxide however gives 2-(4-R-phenyl)-1,3-benzoxazole as a major product (30%) along with the photoreduction, photo-Fries and intramolecular photocyclization products.  相似文献   
975.
Lead(II) 2,2'-bipyridine hexachloroplumba tetetrahydrate was synthesized and investigated by DTA, TG and DTG. IR spectroscopy and other methods enabled the identification of some of the decomposition products. Comparative studies on the corresponding chlorides: [Pb(bipy)]Cl2 and [Pb(bipy)3]Cl2, which can be considered as precursors of the hexachloroplumbate, were also undertaken. X-ray measurements enabled the tentative determination of the crystal structure of [Pb(bipy)]Cl2. Hexachloroplumbate decomposes with the liberation of chlorine, water and organic ligands, and the process is accompanied by the simultaneous transition of Pb(IV)→Pb(II). Chlorides release only ligands upon heating. Residues comprised always PbCl2. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
976.
DFT/B3LYP calculations of the ground-state conformation of eight cyclic and acyclic acetals are presented and compared with experimental data. Results of single-point GIAO/DFT calculations at five different levels of theory show that isotropic shieldings need to be empirically scaled to achieve agreement with experimental chemical shifts. Statistical evaluation of data indicates that the most accurate prediction of 13C chemical shifts is achieved at the MPW1PW91/6-311G** level of theory. An empirical equation describing the relationship between delta values and shielding constants is postulated. This equation has been applied to the non-chair ground-state conformation of the six-membered acetonide and to the conformationally flexible benzodioxonine derivative. The agreement observed between the experimental and predicted chemical shifts shows that calculations at the MPW1PW91/6-311G** level of theory are adequate for addressing questions of conformation.  相似文献   
977.
A novel series of the formula NdSrNi1−xCuxO4−δ were synthesized for various values of x ranging from 0 to 1 in 1 atm of O2 gas flow using conventional solid-state methods and were characterized by powder X-ray diffraction and electrical resistivity measurements. The compounds have been shown to adopt the K2NiF4-type structure. The oxygen stoichiometry of the compounds was determined from thermo-gravimetric analysis (TGA). An analysis of the micro-structure of the neodymium strontium nickel copper oxide is described. All the samples were semi-conducting from room temperature down to 77 K. The effect of Cu2+ incorporation on the structural and electrical properties of NdSrNi1−xCuxO4−δ, 0?x?1, are discussed in terms of Jahn-Teller distortion of the (Ni/Cu)O6 octahedra and mixed valence character of copper.  相似文献   
978.
二茂铁甲酰丙酮缩氨基硫脲金属配合物研究   总被引:4,自引:0,他引:4  
将二茂铁甲酰丙酮与硫代氨基脲在水 -乙醇介质中进行缩合反应 ,得金属有机多齿配体C5H5Fe C5H4COCH2 C(CH3 ) =NNHCSNH2 (简记作 Fc TS) ,该配体分别与 d-过渡金属 [Cu( )、Co( )、Ni( )、Mn( ) ]、 B族金属 [Zn( )、Cd( ) ]及主族金属 [Pb( ) ]乙酸盐反应 ,合成了分子式为 (Fc TS) 2 M(CH3 COO) 2 的 7个新型配合物。经元素分析、IR、UV- Vis,1 H HMR、摩尔电导及固体电导的测定对配合物组成、结构、波谱性质和导电性能进行了研究。  相似文献   
979.
苯乙烯在蚕丝丝胶上接枝共聚的研究   总被引:5,自引:0,他引:5  
<正> 蚕丝丝胶(Silk Sercin简写SS)是由十八种氨基酸缩合而成的天然旦白,占蚕茧重量的20—30%,由于它溶于水,在缫丝过程中随废水而流失。我们曾对丝胶-金属络合物的制备及其对DL和L-3,4二羟基苯丙氨酸氧化催化活性进行了研究。本文研究了苯乙烯(St)在丝胶上接枝共聚的机理及规律,用红外光谱、差示扫描量热法、热重  相似文献   
980.
A novel oligothiophene derivative containing the triphenylamine moiety with high glass transition temperature (Tg; 135 °C), 5,5′‐{bis[4‐di(4‐thiophenyl)amino]phenyl}‐2,2′‐bithiophene (TTPA‐dimer) was synthesized by the dimerization of tris[4‐(2‐thienyl)phenyl]amine (TTPA) with a palladium catalysis. Some types of electroluminescent (EL) devices that use the amorphous material for a hole‐ and an electron‐transporting with an emitting layer were fabricated. These devices emitted a bright green‐yellowish light (λemi; around 510 nm) with a small full width at half maximum (FWHM) rather than that of Alq3. The single layer EL device showed a maximum luminance of 221 cd/m2 at 8 V (0.06 lm/W at 100 cd/m2). On the other hand, the double layer (TTPA‐dimer/Alq3) EL device that used Alq3 as the electron transport material was increased up to 10830 cd/m2 at 12 V (0.89 lm/W at 300 cd/m2) and with a lower turn‐on voltage (3.2 V at 0.1 cd/m2) than other types of EL devices. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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