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Osteocyte viability and bone density in cadmium chloride-induced osteoporosis ameliorated with Pilostigma thonningii stem bark-extracted D-3-O-methy-chiroinositol 被引量:2
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作者 Edwin Aihanuwa Uwagie-Ero Clifford Nwabugwu Abiaezute +4 位作者 Chinaka O.Nwaehujor Theophilus Okafor Nnaji Eugene Amienwanlen Odigie Oyetunde Kazeem Ekeolu Ohiemi Benjamin Ocheja 《Animal Models and Experimental Medicine》 CSCD 2019年第1期25-33,共9页
Background : This study examined the ameliorative effect of D-3-O-methylchiroinositol, isolated from the stem bark of Piliostigma thonningii, on cadmium chloride-induced osteoporosis in male Wistar rats. Methods : Thi... Background : This study examined the ameliorative effect of D-3-O-methylchiroinositol, isolated from the stem bark of Piliostigma thonningii, on cadmium chloride-induced osteoporosis in male Wistar rats. Methods : Thirty-six rats were assigned to three treatment groups(n = 12). Group A(2 mL distilled water), group B:(2.5 mg/kg b.w. CdCl_2) and group C:(2.5 mg/kg b.w. CdCl_2 and D-3-O-methyl-chiroinositol 2 mg/kg b.w.). Bone ash, calcium, phosphate, magnesium, and zinc content, as well as bone histological changes were determined at the end of months 1, 2, and 3. Results : There were significant differences( P ≤ 0.05) in the weight of the cervical, tibia, and femoral bones in all groups. The serum concentration of CdCl_2 was significantly different across the three groups with time. There was significant variation( P < 0.005) in the mean bone ash across groups. The concentration of OH-proline was significantly different( P < 0.0001) across groups. There were significant differences( P < 0.0001) in bone calcium, magnesium, zinc, and phosphorus concentrations. Histology revealed high levels of bone mineralisation in the CdCl_2-treated group, indicative of osteoporosis with hypertrophied osteocytes, while the femur of Wistar rats treated with D-3-O-methyl-chiroinositol showed bone trabeculae and viable osteocytes. Conclusion : The study concluded that D-3-O-methyl-chiroinositol extract from Piliostigma thionningii stem bark ameliorated cadmium chloride-induced osteoporosis in male Wistar rats. 展开更多
关键词 cadmium chloride D-3-o-methyl-chiroinositol oSTEoCYTES oSTEoPoRoSIS toxicity AMELIoRATIoN
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Effect of Polyethylene Glycol on the Properties of γ-Al_2O_3 Formation by Polyaluminum Chloride
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作者 赵长伟 王孝年 +2 位作者 何劲松 王园园 栾兆坤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期1034-1038,共5页
A polyaluminium chloride solution with high Al 13 content self-prepared was used as material for preparing the spherical γ-Al 2 O 3 by the sol-gel and oil-drop method. Polyethylene glycol with different molecular mas... A polyaluminium chloride solution with high Al 13 content self-prepared was used as material for preparing the spherical γ-Al 2 O 3 by the sol-gel and oil-drop method. Polyethylene glycol with different molecular mass was used as surfactant to investigate the effect on property of γ-Al 2 O 3 . The physical property was characterized by 27 Al NMR (nuclear magnetic resonance) spectra, X-ray diffraction, FT-IR (Fourier transform infrared spectroscopy) and TG-DTA (thermogravimetric-differential thermal analysis). The results showed that surface area, pore volume and pore size of γ-Al 2 O 3 all increased with the increase of polyethylene glycol molecular mass in the experimental research range, and polyethylene glycol 10000 was the most suitable pore forming additive. γ-Al 2 O 3 with surface area of 339 m 2 ·g 1 , pore volume of 0.59 cm 3 ·g 1 and pore diameter of 6.9 nm were obtained at 450 °C. 展开更多
关键词 γ-Al 2 o 3 polyaluminum chloride PREPARATIoN polyethylene glycol
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Synthesis of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode material by chloride co-precipitation method 被引量:5
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作者 李灵均 李新海 +3 位作者 王志兴 伍凌 郑俊超 李金辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第S1期279-282,共4页
LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical me... LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical measurements.Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750℃with 105%lithium content has fine particle sizes around 200 nm and homogenous sizes distribution.The initial discharge capacity for the powder is 184 mA·h/g between 2.7 and 4.3 V at 0.1C and room temperature. 展开更多
关键词 lithium ion battery LiNi0.8Co0.1Mn0.1o2 chloride co-precipitation Rietveld refinement
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Preparation and Characterization of γ-Al2O3 by Polyaluminum Chloride with High Al13 Content 被引量:1
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作者 赵长伟 王孝年 +3 位作者 何劲松 栾兆坤 彭先佳 贾智萍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期333-336,共4页
In this paper a polyaluminum chloride solution with high Al13 content was prepared and used as raw material for preparation ofγ-Al2O3.The texture and crystalline phase of the prepared alumina samples were characteriz... In this paper a polyaluminum chloride solution with high Al13 content was prepared and used as raw material for preparation ofγ-Al2O3.The texture and crystalline phase of the prepared alumina samples were characterized by energy dispersive X-ray spectroscopy(EDX) ,X-ray diffraction,transmission electron microscope(TEM) and nuclear magnetic resonance(NMR) analyses.The effects of alkaline solution and calcination temperature were investigated.The results showed that alkaline solution including NH3·H2O and NaOH had little effect on the alumina sample formation.The impurities of NH4Cl and NaCl in solution can be removed through repeated washing by EDX analysis.Calcination temperature had a significant effect on alumina crystal phase.The alumina sample can transform completely toγ-Al2O3 in the subsequent heating from 600°C to 800°C.It is very interesting that Al13 can be existed inγ-Al2O3 phase even after calcinations.The results indicate that polyaluminum chloride with high Al13 content is an effective material to prepareγ-Al2O3. 展开更多
关键词 Γ-AL2o3 polyaluminum chloride PREPARATIoN AL13
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Effect of Silyl Moiety on the Reaction of O,O'-Phenylenephosphoryl Chloride with N-Silylvaline Silyl Ester
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作者 Qian WANG Hai Yan LU Yu Fen ZHAO (Bioorganic Phosphorus Chemistry Laboratory, Department of Chemistry Tsinghua University, Beijing 100084) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
N-Trimethylsilylvaline trimethylsilyl ester IIa, N-triethylsilylvaline triethylsilyl ester IIb and N-tert-butyldimethylsilylvaline tert-butyldimethylester IIc showed evidently different reactivities with O,O'-phen... N-Trimethylsilylvaline trimethylsilyl ester IIa, N-triethylsilylvaline triethylsilyl ester IIb and N-tert-butyldimethylsilylvaline tert-butyldimethylester IIc showed evidently different reactivities with O,O'-phenylenephosphorylchloride The formation speed of the fmal spiro-bicyclic pentacoordinated phosphorus compounds IV depends on the intramolecular transfer ability of the silyl moiety crucially 展开更多
关键词 MHz Phenylenephosphoryl chloride with N-Silylvaline Silyl Ester Effect of Silyl Moiety on the Reaction of o o
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Direct spray pyrolysis of aluminum chloride solution for alumina preparation
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作者 吕国志 张廷安 +3 位作者 王龙 马思达 豆志河 刘燕 《Journal of Central South University》 SCIE EI CAS 2014年第12期4450-4455,共6页
The effects of pyrolysis mode and pyrolysis parameters on Cl content in alumina were investigated, and the alumina products were characterized by XRD, SEM and ASAP. The experimental results indicate that the spray pyr... The effects of pyrolysis mode and pyrolysis parameters on Cl content in alumina were investigated, and the alumina products were characterized by XRD, SEM and ASAP. The experimental results indicate that the spray pyrolysis efficiency is higher than that of static pyrolysis process, and the reaction and evaporation process lead to a multi-plot state of the alumina products by spray pyrolysis. Aluminum phase starts to transform into γ-Al2O3 at spray pyrolysis temperature of 600 °C, which is about 200 °C lower than that of static pyrolysis process. The primary particle size of γ-Al2O3 product is 27.62 nm, and Cl content in alumina products is 0.38% at 800 °C for 20 min. 展开更多
关键词 spray pyrolysis aluminum chloride solution γ-Al2o3 phase transformation
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Electrochemical codeposition of Mg-Li-Gd alloys from LiCl-KCl-MgCl_2-Gd_2O_3 melts 被引量:4
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作者 魏树权 张密林 +3 位作者 韩伟 颜永得 张萌 张斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期825-829,共5页
Mg-Li-Gd alloys were prepared by electrochemical codeposition from LiCl-KCl-MgCl 2 -Gd 2 O 3 melts on molybdenum electrode with constant current density at 823 and 973 K. The microstructure of the Mg-Li-Gd alloys was ... Mg-Li-Gd alloys were prepared by electrochemical codeposition from LiCl-KCl-MgCl 2 -Gd 2 O 3 melts on molybdenum electrode with constant current density at 823 and 973 K. The microstructure of the Mg-Li-Gd alloys was analyzed by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM). The results show that magnesium and gadolinium deposit mainly in the first 30 min, and the alloy obtained contains 96.53% Mg, 0.27% Li and 3.20% Gd (mass fraction). Then, the reduction of lithium ions occurs quickly. The composition of alloy can be adjusted by controlling electrolysis time or Gd 2 O 3 concentration in LiCl-KCl melts. With the addition of Gd into Mg-Li alloys, the corrosion resistance of the alloys is enhanced. XRD results suggest that Mg 3 Gd and Mg 2 Gd can be formed in Mg-Li-Gd alloys. The distribution of Gd element in Mg-Li-Gd alloys indicates that Gd element mainly distributes at the grain boundaries of Mg-Li-Gd alloys. 展开更多
关键词 electrochemical codeposition Mg-Li-Gd alloy chloride melt galvanostatic electrolysis GD2o3
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An Investigation on the Electrochemical Characteristics of Ta<sub>2</sub>O<sub>5</sub>-IrO<sub>2</sub>Anodes for the Application of Electrolysis Process 被引量:3
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作者 Joo-Yul Lee Dae-Keun Kang +1 位作者 KyuHwan Lee DoYon Chang 《Materials Sciences and Applications》 2011年第4期237-243,共7页
The electrochemical characteristics of Ta2O5-IrO2 electrodes prepared from different chemical compositions and coating methods were observed by using cyclic voltammetry, potentiostatic polarization, galvanostatic pola... The electrochemical characteristics of Ta2O5-IrO2 electrodes prepared from different chemical compositions and coating methods were observed by using cyclic voltammetry, potentiostatic polarization, galvanostatic polarization and scanning electron microscopy. The efficiency for chloride oxidation and oxygen evolution processes was not only influenced by the chemical composition but also by the surface morphology of the oxide electrode which was susceptible to the ratio of the two components and the coating method. Ta2O5(50)-IrO2(50) electrodes revealed the highest catalytic activity for the chloride ion oxidation and oxygen evolution reaction because they had the largest effective surface area. The durability of the oxide electrodes in the accelerated life tests was improved as the thickness of the oxide layer increased and the ratio of [IrO2] to [Ta2O5] approached 80/20. 展开更多
关键词 Ta2o5-Iro2 Anode chloride oxidation oxygen Evolution Accelerated Life Test Corrosion Resistance
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Thermochemical studies on complex of [Sm(o-NBA)_3phen]_2 被引量:2
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作者 肖圣雄 张建军 +3 位作者 李旭 李强国 任宁 李环 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第1期12-15,共4页
A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution e... A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution enthalpies of SmCl3·6H2O(s), o-HNBA(s) and phen·H2O(s) in mixed solvent (VHCl :VDMF :VDMSO=2:2:1) were determined by calorimetry at 298.15 K. The enthalpy change of the reaction was determined to be rHmΔ θ=252.49±1.60 kJ/mol. Using the relevant data in the literature and a thermochemical recycle... 展开更多
关键词 rare earth complex samarium chloride hexahydrate o-nitrobenzoic acid 1 10-PHENANTHRoLINE THERMoCHEMICAL
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Measurements of Enthalpy Change of Reaction of Formation, Molar Heat Capacity and Constant-Volume Combustion Energy of Solid Complex Yb(Et_2dtc)_3(phen) 被引量:2
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作者 宋伟明 胡奇林 +3 位作者 常旋 陈三平 谢钢 高胜利 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期155-162,共8页
A ternary solid complex Yb(Et2dtc)3(phen) was obtained from the reaction of hydrous ytterbium chloride with sodium diethyldithiocarbamate (NaEt2dtc), and 1, 10-phenanthroline (o-phen·H2O) in absolute etha... A ternary solid complex Yb(Et2dtc)3(phen) was obtained from the reaction of hydrous ytterbium chloride with sodium diethyldithiocarbamate (NaEt2dtc), and 1, 10-phenanthroline (o-phen·H2O) in absolute ethanol. The bonding characteristics of the complex were characterized by IR. The result shows Yb3^+ bands with two sulfur atoms in the Na(Et2dtc)3 and two nitrogen atoms in the o-phen. The enthalpy change of liquid-phase reaction of formation of the complex △rHm^θ(Ⅰ), was determined as being (-24.838±0.114) kJ·mol^-1 at 298.15 K, by an RD-496 Ⅲ type heat conduction microcalormeter. The enthalpy change of the solid-phase reaction of formation of the complex △rHm^θ(s), was calculated as being (108.015±0.479) kJ·mol^-1 on the basis of an appropriate thermochemistry cycle. The thermodynamics of liquid-phase reaction of formation of the complex was investigated by changing the temperature during the liquid-phase reaction. Fundamental parameters, the activation enthalpy, △H≠^θ, the activation entropy, △S≠^θ, the activation free energy,△G≠^θ, the apparent reaction rate constant k, the apparent activation energy E, the pre-exponential constant A, and the reaction order n, were obtained by a combination of the reaction thermodynamic and kinetic equations with the data from the thermokinetic expenments. At the same time, the molar heat capacity of the complex cm. p, Was determined to be (86.34± 1.74) J·mol^-1·K^-1 by the same microcalormeter. The constant-volume combus- tion energy of the complex, △cU, was determined to be ( - 17954.08 ± 8.11) kJ·mol^-1 by an RBC-Ⅱ type rotating-bomb calo- rimeter at 298.15 K. Its standard enthalpy of combustion, △cHm^θ, and standard enthalpy of formation, △fHm^θ, were calculated to be (- 17973.29±8.11) kJ·mol^-1 and (-770.36±9.02) kJ·mol^-1, respectively. 展开更多
关键词 hydrous ytterbium chloride sodium dinedithiocarbamate (NaEt2dtc) 1 10-phenanthroline o-phen·H2o THERMoCHEMISTRY rare earths
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Thermochemical properties of Ternary Complex Yb[(C_5H_8NS_2)_3(C_(12)H_8N_2)]
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作者 Shuai Qi Chen Sanping Gao Shengli Meng Xiangxin Yang Xuwu Shi Qizhen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期715-715,共1页
A novel ternary solid complex, Yb (C5H8NS2)3 (C12H8N2), was obtained from treating hydrous ytterbium chloride, ammonium pyrrolidin- edithiocarbamate ( APDC ) and 1, 10-phenanthroline (o-phen· H2O) in abso... A novel ternary solid complex, Yb (C5H8NS2)3 (C12H8N2), was obtained from treating hydrous ytterbium chloride, ammonium pyrrolidin- edithiocarbamate ( APDC ) and 1, 10-phenanthroline (o-phen· H2O) in absolute ethanol, and characterized by elemental analysis. The enthalpies of solution of hydrous ytterbium chloride, APDC, o-phen·H2O, the mixture of APDC with o-phen· H2O in absolute ethanol at 298. 15 K, and the enthalpy changes of liquid- phase reaction of formation for Yb ( C5H8NS2 )3 ( C12H8N2) at different temperatures were measured by using a RD496-Ⅲ microcalorimeter. Fundamental paconduction microcalorimeter, determining the specific heat a calculation model for capacity of solid subrameters, the activation enthalpy (ΔH≠^θ), the activation entropy (ΔS≠^θ), the activation free energy (ΔG≠^θ), the apparent reaction rate constant (k), the apparent activation energy ( E ), the pre-exponential constant (A) and the reaction order (n), were obtained by the combination of the thermochemical data of the reaction and kinetic equations with the data of thermokinetic experiments. The enthalpy change of complex formation from the reaction of the regents in solid phase, ΔrH≠^θ(s), was calculated on the basis of an appropriate thermochemical cycle and other auxiliary thermodynamic data. Based on a RD496-Ⅲ heat stance was developed, and the title complex, c m, were accordingly determined. 展开更多
关键词 hydrous ytterbium chloride ammonium pyrrolidinedithiocarbamate (APDC) 1 10-phenanthroline o-phen· H2o THERMoCHEMISTRY rare earths
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O,O-二乙基硫代磷酰氯的合成研究进展
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作者 刘文 穆海平 +1 位作者 李栋 方泽国 《广州化工》 CAS 2023年第16期16-18,30,共4页
以含磷化合物作为原料,通过硫化、氯代等方法合成高品质的O,O-二乙基硫代磷酰氯。本文将对多篇文献所报道的O,O-二乙基硫代磷酰氯的合成途径及中间产物进行归纳总结,并对比工艺流程的优、缺点,探寻高收率、低污染的优质工业生产方法。... 以含磷化合物作为原料,通过硫化、氯代等方法合成高品质的O,O-二乙基硫代磷酰氯。本文将对多篇文献所报道的O,O-二乙基硫代磷酰氯的合成途径及中间产物进行归纳总结,并对比工艺流程的优、缺点,探寻高收率、低污染的优质工业生产方法。结果表明,目前所采用的生产工艺存在一定的改进空间,使用廉价低毒的原料可进一步降低生产所需的成本及“三废”的排放,为企业提高产品的经济效益提供了参考。 展开更多
关键词 o o-二乙基硫代磷酰氯 合成工艺 低污染
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O,O-二乙基硫代磷酰氯的合成工艺优化 被引量:2
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作者 王相承 李丹 +1 位作者 段圣亮 李健 《化学世界》 CAS CSCD 2016年第10期635-637,共3页
对O,O-二乙基硫代磷酰氯的生产工艺进行了优化。利用第一步五硫化二磷与无水乙醇反应中产生的硫化氢副产物通入到第二步硫代磷酰酯(乙基硫化物)的氯化母液中,以硫化氢替代传统工艺中的硫化碱消除反应母液中的氯化硫,达到精制O,O-二乙基... 对O,O-二乙基硫代磷酰氯的生产工艺进行了优化。利用第一步五硫化二磷与无水乙醇反应中产生的硫化氢副产物通入到第二步硫代磷酰酯(乙基硫化物)的氯化母液中,以硫化氢替代传统工艺中的硫化碱消除反应母液中的氯化硫,达到精制O,O-二乙基硫代磷酰氯的目的。相比传统工艺,该路线不仅缩短了工艺流程,同时废水量大幅减少为0.2t/t产品,且高收率得到了易于回收的疏松颗粒物单质硫,提高了目标化合物O,O-二乙基硫代磷酰氯的含量。 展开更多
关键词 o o-二乙基硫代磷酰氯 o o-二乙基硫代磷酰酯 工艺优化
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季铵化N,O-羧甲基壳聚糖的制备及其合成条件优化 被引量:2
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作者 杨蔚 蔡照胜 《化学世界》 CAS CSCD 北大核心 2008年第11期667-670,679,共5页
以N,O-羧甲基化度为85.6%的羧甲基壳聚糖(CM-CTS)为原料,w=0.40的NaOH水溶液为催化剂,3-氯-2-羟丙基三甲氯化铵(CTA)为接枝改性剂,在异丙醇介质中制备了具有良好水溶性的两性壳聚糖-季铵化N,O-羧甲基壳聚糖;分别以产物对模拟废水中的Cd+... 以N,O-羧甲基化度为85.6%的羧甲基壳聚糖(CM-CTS)为原料,w=0.40的NaOH水溶液为催化剂,3-氯-2-羟丙基三甲氯化铵(CTA)为接枝改性剂,在异丙醇介质中制备了具有良好水溶性的两性壳聚糖-季铵化N,O-羧甲基壳聚糖;分别以产物对模拟废水中的Cd+和Cr(Ⅵ)的絮凝去除率为基准对两性壳聚糖的合成条件进行了优化;用IR和1H NMR对产物的结构进行了表征。研究结果表明产物Cr(Ⅵ)的去除率更适宜作为合成条件的优化基准,且对应的优化条件为:季铵化反应时间为10.0 h,反应温度为60.0℃,mNaOH/mCM-CTS=0.50,mCTA/mCM-CTS=1.5;在此条件下合成产物对Cr(Ⅵ)的最大絮凝去除率为93.16%,对Cd2+的最大絮凝去除率98.52%。 展开更多
关键词 N o-羧甲基壳聚糖 3-氯-2-羟丙基三甲基氯化铵 接枝改性 季铵化N o-羧甲基壳聚糖 正交实验
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微波作用下壳聚糖的O-苄基化反应 被引量:10
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作者 董奇志 郭振楚 谭凤娇 《合成化学》 CAS CSCD 2001年第6期560-562,共3页
以浓 Na OH水溶液作为碱性试剂和载体 ,在相转移催化剂存在和微波辐射下 ,壳聚糖与氯化苄能迅速地发生反应 ,生成相应的 O-苄基化产物 。
关键词 壳聚糖 o-苄基化 相转移催化剂 微波作用 氯化苄 氢氧化钠
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合成中间体O,O-二乙基硫代磷酰氯的工艺改进 被引量:5
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作者 田昌明 张海滨 +1 位作者 张小宏 陆银君 《现代农药》 CAS 2006年第6期14-15,共2页
以五硫化二磷为原料,在催化剂三乙胺存在下,与无水乙醇反应合成乙基硫化物,再与氯气反应,最后经硫化钠和氢氧化钠的混合物精制,得到纯度≥99%的O,O-二乙基硫代硫酰氯,总收率达到89%以上。
关键词 o o-二乙基硫代硫酰氟 五硫化二磷 催化剂 三乙胺
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Effects of Calcium on the GABA<sub>A</sub>-Coupled CI<sup>-</sup>/HCO<sub>3</sub><sup>-</sup>-ATPase from Plasma Membrane of Rat Brain
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作者 Sergey A. Menzikov Marina V. Kalinina 《Advances in Enzyme Research》 2014年第2期82-91,共10页
The work is a study of the influence of Ca2+ (0.01 - 1 mM) on neuronal CI-, HCO3-, -ATPase complex: an enzyme that is a CI--pump which is functionally and structurally coupled to GABAA-receptors. It is found that infl... The work is a study of the influence of Ca2+ (0.01 - 1 mM) on neuronal CI-, HCO3-, -ATPase complex: an enzyme that is a CI--pump which is functionally and structurally coupled to GABAA-receptors. It is found that influence of Ca2+ on the multifunctional complex starts at concentration of 50·M and at concentration of 0.1 mM, it reduces the “basal” one and increases the CI-, HCO3-, -stimulated Mg2+-ATPase activities. GABA (0.1 - 100μM) activates the “basal” Mg2+-ATPase activity in the ab-sence of calcium. The effect of GABA on the enzyme in the presence of 0.01 ·M Ca2+ does not change. At the same time, 1 mM Ca2+eliminates the GABA effect on the “basal” Mg2+-ATPase activity. Competitive blocker of GABAA-receptors bicuculline (5 - 20 μM) in the absence of Ca2+ ions elimi-nates the stimulation of the “basal” Mg2+-ATPase by anions. When 0.25 mM Ca2+ is added to the in-cubation medium the inhibitory bicuculline effect on the enzyme does not appear. We found that 0.1 mM o-vanadate (protein tyrosine phosphatase blocker) reduces the GABA-activated ATPase activity. At the same time, 0.1 mM genistein (a protein tyrosine kinase blocker) has no effect on enzyme activity. In the presence of Ca2+ (0.25 mM), the effect of o-vanadate on the “basal” and CI-, HCO3-, -ATPase activities does not appear. It is shown for the first time that high concentrations of Ca2+prevent the action of GABAA-ergic ligands on the study ATPase. It is assumed that there is the involvement of protein kinases and protein phosphatases in the modulation of the enzyme activity by calcium. The observed effect of calcium on the ATPase may play an important role in the study of the mechanisms of epileptogenesis and seizure activity. 展开更多
关键词 Mg2+-ATPase chloride Bicarbonate CALCIUM Rat Brain Plasma Membranes GABAA-Ergic Drugs o-Vanadate Genistein
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非聚醚型O/W稠油破乳剂的合成与性能研究 被引量:5
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作者 郭睿 张菲 +2 位作者 王晓霞 祁文杰 唐宏科 《现代化工》 CAS CSCD 北大核心 2015年第11期95-98,100,共5页
以苯乙烯、甲基丙烯酸丁酯、丙烯酰胺和甲基丙烯酰氧乙基三甲基氯化铵为合成单体,利用氧化还原引发剂过硫酸铵/亚硫酸氢钠并通过乳液聚合法合成了O/W稠油破乳剂,并用红外光谱和核磁共振氢谱对其结构进行了表征。研究了反应温度、反应时... 以苯乙烯、甲基丙烯酸丁酯、丙烯酰胺和甲基丙烯酰氧乙基三甲基氯化铵为合成单体,利用氧化还原引发剂过硫酸铵/亚硫酸氢钠并通过乳液聚合法合成了O/W稠油破乳剂,并用红外光谱和核磁共振氢谱对其结构进行了表征。研究了反应温度、反应时间、乳化剂用量和单体质量分数对产率的影响。通过正交实验确定出最佳反应条件。破乳性能测试表明,在最佳条件下合成的O/W破乳剂的脱水率达到85.2%,水中含油量为53 mg/L,破乳性能优于工业上用的OX-932破乳剂,该O/W破乳剂对胜利油田孤东稠油具有良好的破乳效果。 展开更多
关键词 o/W稠油破乳剂 苯乙烯 甲基丙烯酸丁酯 丙烯酰胺 乳液聚合法 甲基丙烯酰氧乙基三甲基氯化铵
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电聚合o-ImBPTPPMn(Ⅲ)Cl膜修饰玻碳电极同时测定抗坏血酸和多巴胺 被引量:12
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作者 邓雪蓉 王立世 +2 位作者 张水锋 刘笑笑 莫金垣 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第5期637-641,共5页
用循环伏安法在强酸性水溶液中制备出氯化5-邻[4-(1-咪唑基)丁氧基]苯基-10,15,20^-三苯基卟啉锰聚合膜修饰玻碳电极.该电极具有良好的电化学活性,对抗坏血酸(AA)及多巴胺(DA)有明显的催化作用,而且在同一缓冲溶液中用微分脉冲伏... 用循环伏安法在强酸性水溶液中制备出氯化5-邻[4-(1-咪唑基)丁氧基]苯基-10,15,20^-三苯基卟啉锰聚合膜修饰玻碳电极.该电极具有良好的电化学活性,对抗坏血酸(AA)及多巴胺(DA)有明显的催化作用,而且在同一缓冲溶液中用微分脉冲伏安法扫描二者峰电位差达240 mV,此时已达到完全分离.将该电极应用于DA和AA的同时测定,其线性范围分别为2.0×10^-6~1.0×10^-4 mol/L和6.5×10^-7~2.6×10^-5 mol/L;检出限分别为1.0 μmol/L和0.39 μmol/L.二者在微分脉冲伏安法扫描时各有独立的电流响应峰,互不干扰.该电极重现性和稳定性好,在空气中放置3个月以上经处理后电化学活性无下降趋势. 展开更多
关键词 膜修饰电极 o-ImBPTPPMn(Ⅲ)Cl 电聚合 玻碳电极 抗坏血酸 多巴胺
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红霉素A9(O-叔丁基二甲基硅)肟的合成 被引量:3
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作者 孙京国 冯玉玲 《精细化工》 EI CAS CSCD 北大核心 2007年第2期162-165,共4页
以红霉素A与盐酸羟胺反应得到红霉素A肟(EMAO,Ⅰ),再以叔丁基二甲基氯硅烷(TBDMSCl)与Ⅰ进行硅醚化反应制备红霉素A9(O-叔丁基二甲基硅)肟(TBDS—EMAO,Ⅱ)。研究了硅醚化反应的溶剂化作用,有机碱催化作用,Z、E异构体的活... 以红霉素A与盐酸羟胺反应得到红霉素A肟(EMAO,Ⅰ),再以叔丁基二甲基氯硅烷(TBDMSCl)与Ⅰ进行硅醚化反应制备红霉素A9(O-叔丁基二甲基硅)肟(TBDS—EMAO,Ⅱ)。研究了硅醚化反应的溶剂化作用,有机碱催化作用,Z、E异构体的活性。实验结果表明,含孤电子对的极性非质子溶剂及相应的有机碱催化剂有助于在含有多个羟基的Ⅰ中进行肟羟基的选择性硅醚化反应。硅醚化反应以THF为溶剂,室温,反应物浓度c(Ⅰ)=0.27—0.53mol/L,硅醚化试剂用量n(TBDMSCl):n(Ⅰ)=1.4:1,有机碱用量n(Et3N):n(Ⅰ)=2.2:1时,收率可达97%。用HPLC分析了产品及相应的异构体,Z-Ⅱ反应活性较E-Ⅱ高。用IR、1HNMR、13CNMR、EIMS以及元素分析确证了相关物质的结构。 展开更多
关键词 红霉素A9(o-叔丁基二甲基硅)肟 硅醚化 叔丁基二甲基氯硅烷
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