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941.
Zou RQ  Bu XH  Zhang RH 《Inorganic chemistry》2004,43(17):5382-5386
Five new eclipsed two-dimensional (2D) coordination polymers, [[Cd(2)(TPT)(2)L(2)](GM(1))(3/2)(H(2)O)](infinity) (1) (TPT = terephthalate, L = 3-(2-pyridyl)pyrazole, GM(1) = terephthalic acid), [[Cd(TPT)L](GM(2))(H(2)O)(2)]( infinity) (2) (GM(2) = L = 3-(2-pyridyl)pyrazole), [[Cd(TPT)L](GM(3))(1/2)(H(2)O)](infinity) (3) (GM(3) = mesitylene), [[Cd(4)(TPT)(4)L(4)](GM(4))(7/2)](infinity) (4) (GM(4) = tetramethylbenzene), and [[Cd(TPT)L](GM(5))(1/2)](infinity) (5) (GM(5) = naphthalene), have been synthesized and characterized by X-ray diffraction. All the five complexes take the similar eclipsed 2D open-channel framework with different guest molecules included in the cavities of their channels. TGA analysis indicates that the eclipsed open-channel frameworks are thermally stable up to 300 degrees C. The porous property of the 2D framework of 5 was also investigated by the XRPD technique, which indicated that the guest molecules included in the open-channel frameworks are removable and the framework is maintained after the removal of the guest molecules. Moreover, complexes 1-5 also display strong blue emission in the solid state.  相似文献   
942.
显微共焦拉曼光谱研究电化学合成聚苯胺膜   总被引:3,自引:0,他引:3  
显微共焦拉曼技术被用来研究电化学合成的聚苯胺(PANI)膜. 研究结果表明:在不同的激发光聚焦深度,聚苯胺膜的拉曼光谱有明显变化.从而反映出聚苯胺膜的掺杂程度在膜生长过程中随膜厚度的增长而增加. 并由X射线电子能谱(XPS)和紫外吸收光谱(UV)分析证实.  相似文献   
943.
Liu TF  Sun HL  Gao S  Zhang SW  Lau TC 《Inorganic chemistry》2003,42(16):4792-4794
Two three-dimensional (3D) malonate bridged networks, [Cu(mal)(DMF)](n) (1) and [[Cu(mal)(0.5pyz)].H(2)O](n) (2), have been synthesized in H(2)O-DMF solution. Compound 1 exhibits ferromagnetic ordering below 2.6 K (T(c)), and 2 displays a metamagnetic behavior below 3.2 K (T(N)).  相似文献   
944.
Splenectomy has been reported to improve liver fibrosis in patients with cirrhosis and hypersplenism. However, the mechanisms remain unclear. Tumor necrosis factor superfamily 14 (TNFSF14; also known as LIGHT) is highly expressed in the context of fibrosis and promotes disease progression in patients with fibrotic diseases such as pulmonary and skin fibrosis. Here, we determined whether splenectomy controls the production of LIGHT to improve liver fibrosis. Splenectomy reduced serum LIGHT levels in cirrhotic patients with hypersplenism and a ConA-induced liver fibrosis mouse model. Blocking LIGHT resulted in the downregulation of TGF-β1 in RAW264.7 cells. LIGHT treatment of RAW264.7 and JS1 cells in coculture regulated transforming growth factor-β1 (TGF-β1) expression through the activation of JNK signaling. Small interfering RNA-mediated silencing of lymphotoxin β receptor (LTβR) in macrophages resulted in pronounced decreases in the levels of fibrosis and αSMA in JS1 cells. These results indicated that LIGHT bound to LTβR and drove liver fibrosis in vitro. Blocking TGF-β1 abolished the effect of LIGHT in vitro. Furthermore, the administration of recombinant murine LIGHT protein-induced liver fibrosis with splenectomy, while blocking LIGHT without splenectomy improved liver fibrosis in vivo, revealing that the decrease in fibrosis following splenectomy was directly related to reduced levels of LIGHT. Thus, high levels of LIGHT derived from the spleen and hepatic macrophages activate JNK signaling and lead to increased TGF-β1 production in hepatic macrophages. Splenectomy attenuates liver fibrosis by decreasing the expression of LIGHT.Subject terms: Tumour-necrosis factors, Liver fibrosis, Hepatic stellate cells, Liver cirrhosis, Experimental models of disease  相似文献   
945.
反相高效液相色谱法测定人血浆中曲尼司特浓度   总被引:1,自引:0,他引:1  
赵飞浪  袁倚盛  谭力  张昕 《色谱》1998,16(1):78-79
 报道了用反相高效液相色谱法测定人血浆中曲尼司特浓度。以甲醇-磷酸二氢钾缓冲液(60∶40,V/V;pH4.2)为流动相,色谱柱采用YWG-C18不锈钢柱,紫外333nm波长检测,血浆样品经甲醇沉淀蛋白后直接进样测定。血浆浓度在0.65~40mg/L范围内线性良好,方法的平均回收率为100.0%±4.1%。血浆最低检测浓度为0.2mg/L。对10名健康志愿者口服200mg曲尼司特后不同时间的血药浓度进行了测定。  相似文献   
946.
二点滴定法研究   总被引:5,自引:0,他引:5  
张大伦  程春华 《分析化学》1998,26(11):1376-1379
就二点滴定法的原理,方法和应用进行了讨论,导出了二点滴定法计算公式。讨论了滴定剂加入量与测定结果准确度的关系。已用本法对标样样液及试样进行了多次测定,测定结果相对误差及相对标准偏差约0.2%。本法简便,快速,准确,且昨达于任何滴定类型的通用方法。  相似文献   
947.
Mechanical properties of BPDA-ODA polyimide fibers   总被引:1,自引:0,他引:1  
An aromatic polyimide was synthesized via a one-step polycondensation reaction between biphenyltetracarboxylic dianhydride (BPDA) and 4,4′-oxydianiline (ODA) in p-chlorophenol. The polyimide (BPDA-ODA) solution dopes were spun into fibers by means of dry-jet wet spinning. The as-spun fibers were drawn and treated in heating tubes for improving the mechanical properties. The thermal treatment on the fibers resulted in a relatively high tensile strength and modulus. Thermal mechanical analysis (TMA) was employed to study the linear coefficient of thermal expansion (CTE). Thermal gravimetry analysis (TGA) spectra showed that the BPDA-ODA fibers possessed an excellent property of thermo-oxidative degradation resistance. The sonic modulus Es of the polyimide fibers was measured.  相似文献   
948.
表面活性剂对纤维素接枝共聚物溶液粘度性质的影响   总被引:1,自引:0,他引:1  
研究了阴离子十二烷基硫酸钠(SDS)、阳离子十六烷基三甲基溴化铵(CTAB)和非离子聚乙二醇辛基苯基醚(OP)等三种不同类型的表面活性剂对疏水化水溶性两性纤维素接枝共聚物(CGAO)溶液粘度性质的影响.结果表明,在SDS和OP的临界胶束浓度(cmc)附近,CGAO溶液粘度最大,SDS引起CGAO粘度的变化大于OP;即使在CTAB的cmc附近,随着CTAB浓度的增加,CGAO的粘度一直呈下降趋势;非疏水改性的纤维素接枝共聚物的溶液粘度随SDS或CTAB浓度的增加而下降,但几乎不随OP浓度的增大而变化.此外,通过凝胶渗透色谱法测得的保留时间证实了SDS、CTAB和OP与CGAO之间的疏水缔合作用.  相似文献   
949.
二-(二苯基膦)甲烷(dppm)是一种易与金属形成多核络合物的有机膦配体。我们用dppm作为配体合成了一系列银的多核络合物,并对其结构进行了研究。本文报导了其中一个双核化合物[Ag_2(dppm)_2(Py)_2(μ-Cl)]ClO_4的合成及晶体结构、分子结构的测定。  相似文献   
950.
A novel non-linear Raman spectroscopic technique, which can be used to characterize the chemical composition of the interface region of volatile aerosol particles, is described. The technique is morphology-dependent stimulated Raman scattering (MDSRS). We discuss the phenomenology behind this new optical probe, and present experimental results which show that this technique can be used as quantitative spectroscopic tool. We outline the potential application of MDSRS to in situ gas—aerosol kinetics and dynamics studies.  相似文献   
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