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941.
四磺化酞菁钴在微乳液、醇-水体系中的二聚现象研究   总被引:2,自引:0,他引:2  
采用分光光度法研究了四磺化酞菁钴(CoTSPc),在微乳液(TritonX-100-壬烷-正戊醇-水)、醇-水(甲醇、乙醇、丙醇)体系中的二聚现象,计算了CoTSPc的二聚常数KD。结果表明,CoTSPc的二聚常数KD值随着微乳液中表面活性的浓度及醇-水溶液的介电常数的增加而减小。  相似文献   
942.
Anionic clay, ZnCuCoAlNO3 and its polyoxometalate intercalates were synthesized, and were characterized by XRD, IR, 31PMAS NMR, DTA and elemental analysis. The pillared products are found to be effective catalysts for oxidation of cyclohexene with molecular oxygen under mild reaction conditions  相似文献   
943.
研究二维光学薄膜SnO2:TiO2在乙醇、丙酮、氨蒸汽中的气敏反射光谱,发现它与厚膜(膜厚20μm)的气敏反射光谱有明显的差异,它的反射光强在气体浓度较低时随气体浓度增加而增强,气体浓度较高时则现象相反,并且它的反射峰会发生位移。利用不同气体的反射峰的气敏特性,可制成有气体选择性的气敏光纤传感器。  相似文献   
944.
急性脑血管病患者血清元素的测定   总被引:3,自引:1,他引:3  
采用高频等离子体发射光谱法测定了34例脑梗塞、33例脑出血和对照组27人血清锌、铜、锰、铬、镁、钼、锶、铁、钛、钡、镉和钙共12种元素的含量。结果显示脑梗塞和脑出血组血清锌和锌/铜比值显著高于对照组;锰和钼含量仅在脑梗塞组明显增高,锶仅在脑出血组显著增高,而其它几种元素疾病组与对照组无显著性差异。伴有高血糖、高血脂和高血压的病人,其血铬含量显著降低,表明锌、锌/铜比值、锰、钼、锶、铬元素与急性脑血  相似文献   
945.
医药品冰片有天然品与合成品之分,天然品有:由龙脑香科(Dipterocarpaceae)植物龙脑香(Dryobalanops aromatica G aertn,f.)制得的结晶,称龙脑香冰片;白菊科(Compositae)植物艾纳香(Blumea balsamifera DC.)所得的结晶,名艾片。艾片因其晶形似梅花片,又有梅片之称,根据梅花片状又分为大梅片,二梅片,三梅片,天然品化学成分为龙脑(Borneol,Ⅰ),合成冰片(又名合成龙脑),除含龙脑外尚含较大量的异龙脑(ISO-borneol,Ⅱ)  相似文献   
946.
Recent advances In the theory of ∑ relationships lead to the Investigation of moments needed to derive the relavant joint probability densities. These together with the linear theory of relationships, make possible the calcualtion of therelationships from ∑1 to ∑2 one by one. The superior performance ofour new ∑4 and ∑r relationships, for example, with respect to the older ∑1 and ∑3 formulas strongly suggests a deeper study of the pertinent moments. In this paper a new concept, the cosine moment, is introduced which, together with a certain integral theorem, permits the derivation of the relevant joint probability densities. These lead in turn to the derivation of all ∑ relationships valid for all the space groups.  相似文献   
947.
We have generated one possible active site structure of Oxyhemocyanin (Oxy-Hc) and two possible active site structures of Oxytyrosinase (Oxy-Ty) using the EHMO method. Oxy-Hc active site has a plane configuration, while Oxy-Ty has boat configuration. When there exist water molecules, two water molecules are connected with the Oxy-Ty active site weakly. Calculations for the reactions of Oxy-Hc and Oxy-Ty (the water-off) with phenol demonstrate that the former reaction is thermodynamically forbidden, while the latter Is realizable.  相似文献   
948.
New coordination number models for square-well (SW) fluids are incorporated with the generalized van der Waals partition function to develop equations of state for both pure and mixture SW fluids. The equations of state have been extensively tested with the Monte Carlo simulation data, of which three sets (18 data points) for the pure SW fluids are produced in this work. The results show that, without any parameters, our model reasonably describes not only the PVT behaviors but also the second and third virial coefficients of the model fluids. In addition, a comprehensive comparison has been made between our models and the other equations of state derived from the Lee-Chao and Lee-Sandler coordination number correlations.  相似文献   
949.
Ag colloidal nanoparticles coated with Eu(TTA)3 · 2H2O complexes were prepared, and it was found that Eu(TTA)3 · 2H2O complexes J-aggregate was formed on the surface of Ag nanoparticles according to a red shift (18.2 nm) in UV–Vis spectra. However, there had similar excitation wavelength, which was attributed to existence of Ag nanoparticles. Highly luminescent properties of Ag colloidal nanoparticles were observed, and it was believed to result from low energy transfer between Eu(III) complexes and Ag and the large electromagnetic field arising from the excitation of surface plasmon polariton of Ag nanoparticles.  相似文献   
950.
Three new metal complexes, Cu(4-Hcba)2(4-cba)2(Py)2 (4-Hcba=4-cyanobenzoic acid) 1 and M[H(4-cba)2]2(Py)2 (M=Ni 2, Co 3), have been prepared by the treatment of 4-Hcba with the respective metal nitrate M(NO3)2 (M=Cu, Ni, Co) in the presence of pyridine (Py). Single-crystal X-ray diffraction analyses (3 is isostructural to 2) show that the obtained complexes are of isolated mononuclear and the metal atoms have distorted octahedral coordination environment. Two different types of intramolecular hydrogen bonds exist: asymmetrical O–HO for 1 and symmetrical OHO for 2 and 3. The crystal packing between the molecular complexes is controlled mainly by T-shaped C–Hπ interactions between pyridine and phenyl rings. Preliminary discussions on IR, UV–VIS and fluorescent spectra have also been carried out.  相似文献   
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