多组分氧化物Ag－Bi－V－Mo－O催化作用的光电子能谱研究

多组分氧化物Ａｇ－Ｂｉ－Ｖ－Ｍｏ－Ｏ催化作用的光电子能谱研究宋伟，李静，窦伯生（中国科学院长春应用化学研究所长春１３００２２）关键词　钼钒酸铋，助剂Ａｇ，ＸＰＳ，Ａｒ~＋刻蚀，氧化还原对于烃类选择氧化反应中复合氧化物的催化作用，普遍认为是Ｒｅｄｏｘ机...

丙烷氧化反应中多组分氧化物Bi－V－Mo－O催化作用的红外光谱研究

丙烷氧化反应中多组分氧化物Ｂｉ－Ｖ－Ｍｏ－Ｏ催化作用的红外光谱研究李静，宋伟，窦伯生（中国科学院长春应用化学研究所长春１３００２２）关键词钼钒酸铋，丙烷，选择氧化，催化作用机理，红外光谱迄今对于含有钼、铋复合氧化物催化剂的活性中心和作用机理存在不同看...

Synthesis and properties of thermotropic liquid crystalline copolyesters containing bis(4-hydroxyphenyl)methanone(V)

A new series of fully aromatic thermotropic liquid crystalline copolyesters were synthesized by thermal polycondensation of p-hydroxybenzoic acid (PHB), terephthalic acid (TPA), resorcinol (RES) and bis (4-hydroxyphenyl) methanone (BHP). The DSC traces of copolyesters exhibited two or three endotherms, the low temperature endotherm(Tm) of which indicated the transition from solid state to anisotropic phase. Observation under polarizing microscope and WAXD measurements suggested that the LC-phase formed immediately above Tm had a nematic character.

EFFECT OF V, NB, AND TA DOPING ON THE 2223 PHASE-FORMATION AND THE CRYSTAL-STRUCTURE IN THE BISRCACUO SYSTEM

X-ray diffraction and electrical and diamagnetic analyses revealed that the 2223 phase was significantly enhanced by high-valence cation (V5+, Nb5+, Ta5+, etc.) doping in BiSrCaCuO samples. The optimum nominal composition was Bi1.6M0.4Sr2Ca2Cu3 O(y)(M =

THE ISOLATION, CHARACTERIZATION AND OXIDATION REACTION OF ACTIVE INTERMEDIATES OF CYTOCHROME-P-450 MODEL SYSTEM OXOCHROMIUM(V) TETRAPHENYLPORPHYRIN COMPLEXES

Oxochromium (V) tetraphenylporphyrin complexes, O = Cr (V) TPP (Cl) PhI. O = Cr-(V) TPP (N3) PhI and O = Cr (V)TPP (p-CH3OC6H4O)1/2PhI were isolated from the reaction of Cr (III) TPP (Cl). Cr (III) TPP (N3) Py or Cr (III) TPP (p-CH3OC6H4O) THF with iodosy

细胞色素P—450模拟体系的活性中间体-氧配位铬(V)四苯基卟啉配合物的分离、表征和氧化反应

氮气保护下二氯甲烷中铬(Ⅲ)四苯基卟琳衍生物在-40℃与亚碘酰苯反应,分离得氧配位铬(V)四苯基叶啉配合物:O=Cr(V)TPP(CI)PhI,O—Cr(V)TPP(N_3)PhI,O—Cr(V)TPP(p-CH_3O-C_6H_4O)1/2PhI.已经元素分析、可见、红外、顺磁、核磁和质谱法结构表征.这些配合物能氧化苯乙烯,环己醇,环己烯和环己烷,可作为细胞色素P—450模拟体系的活性中间体.

EFFECT OF CODOPING SB AND V TO THE BIPBSRCACUO SYSTEM

With XRD, R- T curves, and a.c chi measurements, the doping and codoping effects of Sb and V to a Cu-deficient Pb-doped Bi system have been studied. A sample singly doped with V possesses a T(c) about 2 K lower than that of a sample singly doped with Sb. This is attributed to the different sites of their substitution. It was observed that for promoting 2223 phase formation, Sb and V works cooperatively, and the codoping of Sb may enhance the 2223 phase formed. With a low doping level of Sb, the optimum doping amount of V is 0.3, i.e., with a nominal composition of Bi1.5Pb0.3Sb0.06Sr2Ca2Cu2.4V0.3Oy. A sample in which the 2223 phase is the dominant phase and which has a zero resistance transition temperature of 105 K has been obtained.

丙烷氨氧化V/Sb系复合氧化物催化剂的研究

考察了不同组成的V-Sb-O系复合氧化物对丙烷氨氧化的催化活性.用XRD研究了催化剂的结构,利用程序升温方法研究了催化剂中氧的活动性和表面酸碱性,讨论了催化剂体相和表面结构与催化性能间的关系.结果表明,VSbO_4和Sb_2O_4间的协同作用是影响催化活性的重要因素.

PREPARATION AND STRUCTURE OF HALF-OPEN VANADOCENE, V[2,4-(CH3)2C5H5](C5H5)CO

The half-open vanadocene, V[2,4-(CH3)2C5H5](C5H5)CO, was obtained by the reaction of V[2,4-(CH3)2C5H5](C5H5)PMe3 with CO in petroleum ether at room temperature. Its crystal structure was determined by X-ray diffraction technique. The crystal was monoclinic with space group P2(1)/n, a = 16.614(3), b = 7.636(1), c = 19.128(6) angstrom, beta = 99.92(2)-degrees, V = 2390.5(9) angstrom3, and Z = 8. The final R value was 0.043. The V(1)-CPD(1) (half) (PD = 2,4-(CH3)2C5H5) bonds were shorter (0.038 angstrom) than the V(1)-CCP(1) (half) (CP = C5H5) bonds, averaging 2.224(4) versus 2.262(4) angstrom, respectively. 4V[2,4-(CH3)2C5H5](C5H5)CO has been characterized by IR and EPR methods.

α-羰基烯酮式环二硫代缩醛化学(V)——β,β-1,3-亚丙二硫基-α,β-不饱和芳酮类化合物的合成

β,β-二烷硫基-α,β-不饱和酮类化合物作为一类具多反应中心的活泼中间体在有机合成中的应用,近20年来已引人注目并进行了深入广泛的研究~[1,2].以往的研究大多是针对β,β-二甲硫基-α,β-不饱和酮类化合物1进行的,而对结构相近的β,β-1,3-亚丙二硫基-α,β-不饱和酮类化合物2的研究较少.对于1类的合成,所用碱的选择至关重要~[1].实验证明叔丁醇钠和叔丁醇钾~[3～5]在1类的合成中效果较好.前文~[6]曾以六甲基二硅氨基锂(LHMDS)为碱高

V、Nb、Ta对促进Bi系超导体中2223相生成作用研究

自发现BiSrCaCuO超导体以来,为了稳定2223高T_C相结构、增加其在超导体中的含量,在该体系中引入掺杂元素Pb被公认是最有效的方法。我们系统研究了V~(5+)、Nb~(5+)、Ta~(5+)高价离子的单独掺入Bi系中对

聚甲基丙烯酸胆甾接枝共聚物的合成、结构与性能研究V.PMACE的结晶形态

本文通过透射电子显微镜,扫描电子显微镜研究了聚甲基丙烯酸胆甾接枝共聚物室温结晶态的微细结构,及胆甾侧链含量对结晶的影响。