集化学家与化学教育家于一身的一代化学大师李比希--纪念李比希诞辰200周年

在德国著名化学家李比希诞辰200周年之际，对这位集化学家与化学教育家于一身的一代化学大师对科学和科学教育以及人类社会作出的贡献进行了评述。     

长光路光度法测定中药材中痕量硒

本文研究了用长光路光度法测定痕量硒。在酸性溶液中，Ｓｅ（Ⅳ）催化ＫＣｌＯ３氧化苯肼成偶氮离子，继而与变色酸生成红色偶氮化合物。硒含量在１．０×１０－９～２．０×１０－７ｇ／ｍＬ范围内遵守比尔定律。巯基棉分离后，测定中药材中总硒，获得满意结果。     

8-羟基喹啉对甲基苯酚合锌配合物的合成及光致发光和电致发光性能

有机电致发光 ( EL )技术作为一种有着广阔应用前景的显示技术 ,自 1 987年 [1] 以来已获得了空前迅速的发展 .部分发光器件的亮度、效率和寿命已经达到或接近实用化的程度 .许多有机化合物 [2～ 5] ,包括小分子和聚合物 ,已被用于制备有机 LEDs.应用于有机 EL的化合物很多 ,这为优化和筛选优秀的 EL材料提供了基础 .以 8-羟基喹啉铝为代表的有机金属配合物是一类重要的有机 EL材料 ,这类材料荧光效率高、易于提纯且性质比较稳定 .目前应用于有机 EL金属配合物的发光材料大多配位数均为偶数 ,四配位的 8-羟基喹啉锌配合物 ( Znq2 ) [6…     

聚丙烯酰胺/醋酸铬与聚丙烯酰胺/酚醛胶态分散凝胶的纳米颗粒自组织分形结构

采用原子力显微镜 ,分别对无机交联体系聚丙烯酰胺 Cr3+ 和有机交联体系聚丙烯酰胺 酚醛胶态分散凝胶的微观结构进行了显微图像分析 .发现无论是在有机还是无机交联体系中 ,也无论聚丙烯酰胺和交联剂浓度如何变化 ,在微米尺度上最终形成的都是具有自相似性的树枝状分形图像 ,在更小尺度上则发现单个小树杈分形体都是由纳米级的颗粒紧密堆积而成 .在所研究的胶态分散凝胶体系中 ,树枝状分形结构的形成及其具体的形态取决于聚丙烯酰胺的浓度 ,而交联剂的有无及其多少只对树枝状凝胶分形的几何形态产生一定影响 .实验结果还表明纳米级 (≤ 10 0nm)的胶体颗粒构成的分形结构的凝胶其弹性模量G′比微米级的高出一个数量级 .且粒子尺度越小 ,则凝胶的力学稳定性越强     

Synthesis and Crystal Structure of 3,3′-(Hexane-1,6-diyl)bis(1-acetyl-5,5-dimethylhydantoin),a New Inducer of Differentiation

1 INTRODUCTION Hexamethylenebis[acetamide] (HMBA) is an effective agent in phaseⅡclinical trial[1] that induces differentiation of certain types of tumors to nonmalignant phenotypes. In an attempt to discover more efficient inducers, a number of derivatives of HMBA have been synthesized and evaluated in vitro[2, 3]. The results proved that increasing the number of functional groups could enhance the anticancer activity. In addition, it was evident that compounds with six methylene i…     

卟啉类光敏剂在染料敏化太阳能电池中的应用

染料敏化太阳能电池结合了染料光敏剂和无机半导体的优势，具有较宽的光谱响应范围，制造工艺简单、成本较低，对环境友好，应用前景广阔，因而备受人们的关注。本文以卟啉配合物为主线，介绍光敏太阳能电池的基本构造和光电原理，从改善电池性能的角度，综述了各种卟啉类光敏剂在染料太阳能电池中的应用，讨论了卟啉配合物及其超分子结构对光电转化率的影响机理。     

ORGANIC CHELATING REAGENT ON REDOX ADSORPTION OF ACTIVATED CARBON FIBER TOWARDS Au^3+

Organic chelating reagent influences upon the redox adsorption of activated carbon fibertowards Au3- were systematically investigated. The experimental results indicated that the presenceof organic chelating reagent on activated carbon fiber strongly affects adsorption capacity ofactivated carbon fiber towards Au3+. The reduction-adsorption amount of Au3+ increased three timesby the presence of 8-quinolinol. Furthermore, The reduction-adsorption amount of Au3+ depended onthe pH value of adsorption and temperature.     

Tumor cell detection method using complement-mediated cytolytic reaction and imaging sensor system

A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed for the simple and rapid determination of tumor cells. The present system consists of a CCD image sensor, image memory board, personal computer, and microscope. When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis, a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored before reaction. L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation of the whole system is possible.     

Growth kinetics and phenolics production inGlycine Max cell suspension cultures

Glycine max was used as a model plant cell suspension culture to establish relationships among growth kinetics, phenolics production, elicitor action, and peroxidase activity. Timing of elictor addition through monitoring of peroxidase provided an excellent means of optimizing yields of phenolics and reduced the time span during which phenolics were formed, negating the need for a secondary production medium. We have also determined that calcium and other cellular effectors like polyamines and organic osmolytes, when used in conjunction with elicitors, enhance phenolics production. Calcium directly enhanced elicitation, whereas polyamines and other osmolytes such as glycerol and proline extended cell viability. The study also demonstrated potential for enhancing secondary metabolite production by a combination of elicitation, cell viability stabilizers, and by addition of nutrients at the time of elicitation.     

The recent progress of wide bandgap donor polymers towards non-fullerene organic solar cells

The recent progress of wide bandgap (WBG) donor polymers for non-fullerene polymer solar cells (NF-PSCs) were reviewed in detail, which was classified by D-type and D-A type molecular backbones to discuss the related structure-property correlations and put forward an outlook for future innovations.