二茂铁甲酰丙酮缩氨基硫脲金属配合物研究

将二茂铁甲酰丙酮与硫代氨基脲在水 -乙醇介质中进行缩合反应 ,得金属有机多齿配体C5H5Fe C5H4COCH2 C(CH3 ) =NNHCSNH2 (简记作 Fc TS) ,该配体分别与 d-过渡金属 [Cu( )、Co( )、Ni( )、Mn( ) ]、 B族金属 [Zn( )、Cd( ) ]及主族金属 [Pb( ) ]乙酸盐反应 ,合成了分子式为 (Fc TS) 2 M(CH3 COO) 2 的 7个新型配合物。经元素分析、IR、UV- Vis,1 H HMR、摩尔电导及固体电导的测定对配合物组成、结构、波谱性质和导电性能进行了研究。     

ZnO微晶的水热合成及形貌控制研究

以Zn(NH3)4(Ac)2为前驱体,不加任何模板剂和表面活性剂,低温下通过改变反应条件(如前驱体浓度、反应时间及反应温度),实现了对ZnO微晶形貌和尺度的有效控制.所得花状、蜂窝状、柱状ZnO用X射线衍射仪和扫描电镜进行了鉴定和表征,并初步探讨了不同形貌ZnO微晶的生长机理.     

Cordycedipeptide A, a new cyclodipeptide from the culture liquid of Cordyceps sinensis (Berk.) Sacc

A new cyclodipeptide named as cordycedipeptide A, a new natural compound and two known compound were isolated from the culture liquid of Cordyceps sinensis (BERK.) SACC. Their structures were elucidated as 3-acetamino-6-isobutyl-2,5-dioxopiperazine (1), 3-isopropyl-6-isobutyl-2,5-dioxopiperazine (2) and 3,6-di(4-hydroxy)benzyl-2,5-dioxopiperazine (3) by 1D and 2D-NMR techniques. The cytotoxic assay showed compound 1 had the cytotoxic activities to L-929, A375, and Hela.     

SciFinder-guided rational design of fluorescent carbon dots for ratiometric monitoring intracellular pH fluctuations under heat shock

Intracellular pH plays a significant role in various biological processes, including cell proliferation, apoptosis, metabolism, enzyme activity and homeostasis. In this work, a novel design strategy for the preparation of pH responsive carbon dots (CDs-pH) for ratiometric intracellular imaging was reported. By using SciFinder database, fluorescent CDs-pH with the required pK_a value of 6.84 were rationally designed, which is vital important for precise sensing of intracellular pH. As a result, the synthesized CDs-pH demonstrated robust ability to test pH fluctuations within the physiological range of 5.4-7.4. The CDs-pH was further utilized for fluorescent ratiometric imaging of pH in living HeLa cells, effectively avoided the influence of autofluorescence from native cellular species. Moreover, real-time monitoring of intracellular pH fluctuation under heat shock was successfully realized. This SciFinder-guided design strategy is simple and flexible, which has a great potential to be used for the development of other types of CDs for various applications.     

藉高锰酸钾氧化双乙酰的化学发光反应测定微量锰

研究了高锰酸钾氧化双乙酰的化学发光反应。根据微量Ｍｎ６２＋对上述体系化学发光山峰时间的影响，建立了测定Ｍｎ６２＋的分析方法。该法线性范围为１．０×１０＾－４－８．０×１０＾－６７ｍｏｌ／Ｌ，相对标准偏差为３．５％，检出限为６．０×１０＾－８ｍｏｌ／Ｌ。应用于合金中锰的测定，结果良好。     

5′-鸟苷酸与茜素红S的反应及其在分析化学中的作用

采用UVVis光谱法研究了茜素红S(ARS)与5′鸟苷酸(5′GMP)在pH4.80的弱酸性缓冲溶液中生成络合物的结合反应。与试剂比较,络合物的最大吸收峰红移92nm,测得络合物和表观摩尔吸光系数为ε=1.3×104L·mol-1·cm-1;最大结合数n=10;浓度线性范围0.2～16mg/L;检出限为6.1×10-8mol/L。研究了ARS与5′GMP是分子间作用力的结合反应,并对时间、温度、离子强度对结合反应的影响,以及无机物、生物物质对反应体系的干扰情况进行了初步研究。     

个旧超大型锡多金属矿稀土元素地球化学特征

对比研究了个旧不同类型岩(矿)石(蚀变花岗岩、钙质泥岩、大理岩、矽卡岩矿石、层状矿石和脉状矿石)的稀土元素、微量元素地球化学特征,借以示踪不同类型矿床的成矿物质来源。研究表明不同类型矿石中的稀土元素配分曲线较为相似,成矿物质具有同源性,并与本区的花岗岩具有一定的成因联系。由于其成矿方式的不同,不同类型矿石中的稀土元素特征和矿物组合特征略有差异,脉状矿石和层状矿石中稀土含量相对较少且富集轻稀土,而矽卡岩矿石中稀土含量相对较多且轻、重稀土的含量变化较大。     

丽春红G-高碘酸钾催化光度法测定痕量锇

以Os(Ⅳ )催化高碘酸钾氧化丽春红G(PG)的褪色反应为基础 ,在 90℃加热 1 2min和 5 0 0nm波长处采用固定时间法测定丽春红G吸收值的降低 ,建立了测定痕量锇 (Ⅳ )的新方法。锇 (Ⅳ )的质量浓度在 0～ 0 48μg/L范围内呈良好的线性关系 ,检出限为 6 2× 1 0 - 9mg/L。对 0 4μg/L锇 (Ⅳ )测定的相对标准偏差为 0 71 % (n =1 1 )。催化反应对Os(Ⅳ )和丽春红G均为一级反应 ,催化反应的表观活化能为 78 80kJ/mol。所提出的方法在蒸馏分离后已应用于某些岩矿及冶金产品中锇的测定     

Two-dimensional separation system of coupling capillary liquid chromatography to capillary electrophoresis for analysis of Escherichia coli metabolites

A two-dimensional (2-D) separation system of coupling chromatography to electrophoresis was developed for profiling Escherichia coli metabolites. Capillary liquid chromatography (LC) with a monolithic silica-octadecyl silica column (500 x 0.2 mm ID) was used as the first dimension, from which the effluent fractions were further analyzed by capillary electrophoresis (CE) acting as the second dimension. Field-enhanced stacking was selectively employed as a concentration strategy to interface the two dimensions, which proved to be beneficial for the detection of metabolites. An artificial sample containing 118 standards, some of which lack chromophores or have weak UV absorbance, was used to optimize the 2-D separation system. Under the optimum conditions, 63 components in the artificial sample having absorbance at 254 nm could be well resolved and detected. The utility of the system was demonstrated by comprehensive analysis of E. coli metabolites. Comparing with the previous 2-D separation system we published in Anal. Chem. 2004, 76, 1419-1428, using a longer monolithic column in the first dimension improved the separation efficiency and offered the possibility of increasing the injection volume without compromising the separation efficiency. In the second dimension, field-enhanced stacking was used to improve the concentration sensitivity of the metabolites, and more metabolites in E. coli cell extract were detected and identified using the developed 2-D separation system. In addition, preliminary investigation for future CE-mass spectrometry coupling was also made in the study by using volatile buffers in the capillary LC and CE techniques.     

A rapid and accurate method for the determination of strontium-90 in environmental soil

A rapid and accurate method for the determination of⁹⁰Sr in environmental soil has been developed; the procedure includes soil leaching by hydrochloric acid, oxalate precipitation, decontamination from²¹⁰Bi, separation by HDEHP extraction chromatography column, yttrium oxalate precipitation and -counting. The interference of²¹⁰Bi was found and studies have been made for the decontamination of⁹⁰Y from²¹⁰Bi by Bi₂S₃ precipitation giving a decontamination factor of 1.05·10³. The analytical results obtained by the improved rapid method for 12 soil samples were comparable to that obtained by a previous method within a relative error of 20%. Studies of vertical distribution of⁹⁰Sr in an environmental soil profile have shown that 90% of the⁹⁰Sr deposits in the 30 cm surface soil of the earth with a highest concentration of 3.40 Bq/kg. When 50 g soil was analyzed, the yield of yttrium was 73±17% with a detection limit of 0.26 Bq/kg.