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961.
Studies on the Interaction of Beryllon Ⅲ with Proteins by Voltammetric Technique and its Application 总被引:3,自引:0,他引:3
WeiSUN KuiJIAO XueLiangWANG LuDeLU 《中国化学快报》2003,14(12):1275-1277
A new quantitative determination method of proteins using beryllon Ⅲ by voltammetric technique was developed in this paper. In pH 3.5 Britton-Robinson (B-R) buffer solution, beryllon Ⅲ can bind with human serum albumin (HSA) to form an electro-inactive supermolecular complex. Beryllon Ⅲ has a well-defined voltammetric reduction peak at -0.38 V (vs. SCE) and the addition of protein in this solution can cause the decrease of the reductive peak current. Based on the decrease of the reduction peak current, a new electrochemical method for the determination of HSA was established with linear range of 1.0-40.0 mg/L and the detection limit of 1.0 mg/L. This method is further applied to the determination of real sample of healthy human serum. 相似文献
962.
CHEN Shuixia LUO Ying DONG Guohua ZENG Hanmin Materials Science Institute Zhongshan University Guangzhou China 《Chinese Journal of Reactive Polymers》2002,(2)
1. INTRODUCTION Nuclear explosion and thermal fission of U produce many kinds of nuclide. The major products consist of gaseous materials, in particular the noble gases Xe. In some types of nuclear reactor it is necessary to remove 135Xe from the cooling… 相似文献
963.
A peak/ratio in pyrene-fluorescence spectrum was employed to measure the polarity of micro-environment of chitosan adsorb-ing py--rene molecules. The authors have in the first time detect-ed the pyrene-fluorescence spectrum of chitosan with different degrees of deacetylation (D. D. ), and found the relationship between the flocculaflon of bentonite colloid by chitosan and the peak/ratio values of different molecular weight (M. W. ) and D .D. of chitosan. We find that M.W. plays a key role in the flocculatlon, but D.D. has limited effect on it. From micro-en-vironmental structure of view, it can be proved that the inter-particle bridging rather than charge neutralization dominates the flocculatlon with chitosan. 相似文献
964.
土壤中十四种元素的ICP-AES和ISE的碱熔直接测定 总被引:2,自引:0,他引:2
报道了应用直读型电感耦合等离子体发射光谱(ICP-AES)及离子选择电极(Ion-SelectiveElectrode,简称ISE)成功地测定土壤中十四种难测元素的方法及其精度。土壤样品经过NaOH高温熔融、用水定容后,直接在强碱性溶液中用ICP-AES测定通常较难测定的十三种元素;Se、Mo、B、As、Si、S、Pb、P、Ge、Sn、Sb、Cr、K。通过ISE亦能很好地测定F。 相似文献
965.
XiChengMA NingLUN ShuLinWEN 《中国化学快报》2005,16(2):265-268
Carbon nanotubes were initially chemically modified with an H2SO4-HNO3 treatment, and subsequently activated with Pd-Sn catalytic nuclei via a one-step activation approach. These activated nanotubes were used as precursors for obtaining gold nanoparticles-attached nanotubes via simple electroless plating. This approach provides an efficient method for attachment of metal nanostructures to carbon nanotubes. Such novel hybrid nanostructures are attractive for many applications. 相似文献
966.
采用国产的氢型强阳离子交换(磺化苯乙烯-二乙烯基苯共聚物)色谱柱测定了利巴韦林注射液的含量。色谱柱为国产的氢型强阳离子麦科菲色谱柱(MKF-CIS),流动相为水(稀硫酸调至pH=2.5±0.1),检测波长207nm,流速1.0mL/min,温度65℃。结果表明,MKF-CIS色谱柱可以较准确的测定利巴韦林注射剂含量,在12.5μg/mL~500μg/mL浓度范围内,其浓度与峰面积的线性相关性良好(r=0.9999),平均回收率99.8%,RSD=0.558%。由此,国产麦科菲MKF-CIS色谱柱可以简便、准确、重复性好地用于利巴韦林测定,代替传统的C18硅胶柱及进口的同类型色谱柱。 相似文献
967.
IntroductionThetransitionmetalpolypyridylcoordinationcom poundsastheprobeofDNAstructureandconfigurationhavebeenextensivelystudiedinthepastfewyears .TheyinteracteffectivelywithDNAbychangingthetypeofhet eroaromaticligandormetalcenter.Thosewithphen(phenane… 相似文献
968.
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970.
KaiHuaZHANG JingChangZHANG WeiLiangCAO 《中国化学快报》2005,16(5):667-670
The photocatalytic degradation of polyvinyl chloride (PVC) films by tungstophosphoric acid (HPW) was investigated. The main reason for highly enhanced photodegradation of HPW-doped PVC film was studied and discussed. 相似文献