速灭威与牛血清白蛋白作用的研究

在pH=7.4的生理条件下,应用荧光光谱法研究了速灭威与牛血清白蛋白间相互作用。结果表明:速灭威对牛血清白蛋白的荧光有较强的猝灭作用,测定不同温度下的猝灭常数,证实了速灭威对牛血清白蛋白的荧光猝灭过程机理为静态猝灭。根据猝灭结果计算了不同温度下的结合位点数、结合常数。应用同步荧光光谱法探讨了速灭威对牛血清白蛋白构象的影响。依据f ster非辐射能量转移理论确定受体间的结合距离和能量转移效率。     

复方氯丙那林质量检控的近红外光谱快速分析

基于近红外光纤漫反射技术,利用偏最小二乘法分别建立了复方氯丙那林胶囊的三种药效成分盐酸氯丙那林、盐酸溴己新和盐酸去氯羟嗪的快速同时测定方法。所建立的盐酸氯丙那林、盐酸溴己新和盐酸去氯羟嗪的定量分析多元校正模型的相关系数分别为99.7%、99.4%和99.0%,校正集的均方根残差分别为0.028、0.145和0.250,预测均方根误差分别为0.055、0.120和0.210。由于该方法是在不经任何预处理的情况下的光纤快速同时分析,因此可用于复方氯丙那林的过程质量控制。     

槲皮素类似物关键中间体的合成研究

槲皮素(Quercetin,3,5,7,3',4'-pentahydroxy flavanone)是一种具有多种生理活性的黄酮类化合物,广泛分布于食用和药用植物如洋葱、茶叶、银杏等中[1].槲皮素具有许多重要的生理活性,如心血管保护、抗癌、抗炎、抗过敏、抑制神经功能衰退等[2],多年来学者对它的研究大多局限在槲皮素(图1)羟基上的修饰[3-5].     

保留指数结合准确质量测定对鱼腥草挥发性成分的定性分析

采用顶空-气相色谱-四极质谱法和顶空-气相色谱-飞行时间质谱法对鱼腥草挥发性成分进行检测,运用保留指数结合准确质量测定,分别从鱼腥草茎和叶中鉴定出49、39种挥发性组分,并采用峰面积归一化法测定各组分的相对含量。鱼腥草茎和叶中的挥发性成分差别较大。鱼腥草茎以α-蒎烯(12.24%)、β-蒎烯(22.42%)、月桂烯(11.98%)、乙酸冰片酯(10.97%)、甲基正壬酮(10.83%)为主要成分,而鱼腥草叶则以月桂烯(39.48%)、(Z)-β-罗勒烯(26.52%)、癸醛(10.35%)、桧烯(4.43%)、甲基正壬酮(2.44%)为主。结合保留指数和准确质量测定能显著提高质谱定性的准确性,有利于解决质谱检索时定性不确定的问题。     

合成双醋瑞因的新方法

以芦荟素为原料,经脱苷、氧化反应得到大黄酸(4);4经三氟甲磺酸锌催化的乙酰化反应合成了双醋瑞因,总收率86.2%,其结构经1H NMR,IR和MS确证。     

4-Amino-l,2,4-triazole Resin-supported Palladium Complex as Phosphine-free Catalyst for Suzuki Reaction in Aqueous Phase

1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymme-trical biaryls from arylboronic acids and aryl halides in a single step~([1-3]).However,the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand,which sometimes creates practical problems because organophosphines tend to be expensive,poisonous,and air sensitive.Recently,phosphine-free ligands,such as nitrogen or sulfur-containing ligands~([4-6]) and N-heterocyclic car-benes~([7-12]) have been applied in Suzuki reaction effectively.     

Evolution of Gold Species in an Au/CeO2 Catalyst and Its Impact on Activity for CO Oxidation

An Au/ceria(0.44%, mass fraction) catalyst containing gold ions was prepared by a modified deposition precipitation method, and the evolution of gold ions in the catalyst and its influence on the catalysis of CO oxidation were investigated. It was found that the as-prepared catalyst containing gold ions with high valence could fully oxidize CO at –10 °C initially but was deactivated gradually at low temperatures during the reaction with CO or treatment by unpurified air. The deactivation of the catalyst during CO oxidation or treatment of it by unpurified air was independent and progressive at low temperatures while the activity of the catalyst at relatively high temperatures was maintained well. During the reaction with CO or treatment by unpurified air, the XPS results indicate that gold species evolved from high valence to low valence and the diffuse reflectance UV-Vis spectra show that high valence gold was reduced to charged gold clusters, gold clusters grew to small gold crystals and small gold crystals grew to large gold particles. Accordingly, the high valence gold corresponded to the activity at low temperatures and the metallic gold was active and relatively stable at high temperatures. The turnover frequencies(TOF) of the catalysts treated by different methods at 273 K decreased with the evolution of gold species from high valence to low valence, no maximum of TOF was observed although gold particles in the catalyst attained to about 2―3 nm during the treatment. An Au/ceria catalyst with a gold load of 0.87% (mass fraction) maintained a good activity for CO oxidation within 18 h at room temperature. The catalysts were characterized via transmitted electronic microscopy(TEM), inductively coupled plasma optical emission spectrometry(ICP-OES), X-ray diffraction(XRD) and BET specific surface area and UV-Vis DRS as well.     

应用手持式XRF分析仪快速测定白铜中的Cu、Ni、Co含量

采用国产手持式XRF分析仪快速分析了白铜合金主元素的含量,探讨了白铜合金基体效应对测量结果的影响,采用经验系数法中多元回归分析建立数学模型,较好地校正基体效应,分析白铜合金中铜、镍、钴的平均相对误差分别为0.39%、1.83%、1.59%。     

溶剂萃取法提锂的研究进展

总结了采用溶剂萃取法在盐湖卤水中提取锂资源的三类萃取剂:酸性萃取剂、中性络合萃取剂和碱性萃取剂,分析了三类不同萃取剂在萃取锂工艺过程的优缺点,指出了溶剂萃取法从高镁锂比的盐湖卤水中萃取提锂尚待攻克的技术难题。     

三元钴配合物[Co(NCS)_2(ql)_2](ql=喹啉)的合成及其晶体结构和荧光性质

合成了含异硫氰酸根和喹啉(ql)混合配体的钴配合物[Co(NCS)2(ql)2];利用红外光谱、紫外光谱和X射线单晶衍射等手段对其结构进行了表征;研究了配合物在室温下的荧光发射光谱特性.单晶结构解析结果表明,标题化合物属于单斜晶系,P21/c空间群,晶胞参数为:a=1.486 33(5)nm,b=0.844 44(3)nm,c=1.541 16(5)nm,β=92.093(2),V=1.933 0(2)nm3,Z=4,Dc=1.489 g/cm3,μ=1.116 mm-1,F(000)=884,R1=0.032 2,wR2=0.078 6.配合物中钴离子采用四配位的四面体配位构型,晶体堆积中通过π-π作用形成一维超分子结构.