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231.
Dawson结构钼钒磷杂多化合物对苯酚过氧化氢羟化作用的研究 总被引:14,自引:0,他引:14
Dawson结构钼钒磷杂多化合物对苯酚过氧化氢羟化作用的研究于剑锋,杨宇,吴通好,孙家锺(吉林大学化学系理论化学研究所,长春,130023)关键词Dawson结构钼钒磷杂多化合物,苯酚羟化,过氧化氢苯二酚(DBH)是重要的化工原料.由芳香化合物羟化制... 相似文献
232.
对合肥市16671名1-12个月幼儿的发锌,钙含量进行了测定,并对测定值进行了统计分析。结果表明,锌,钙的含量随着月龄的增加呈直线递减。并给出了发锌,钙含量的趋势线方程,丰富了目前文献给出的发锌,钙的标准值,为及时准确判断周岁内幼儿微量元素锌,钙缺乏程度提出依据。 相似文献
233.
The ESR signals of bilirubin-IXα were studied including the samples treated with free radical generating and inhibiting systems, i.e.X-X0., Fe/EDTA, SOD, mannitol/ascorbate, DTPA, KCN et al.These stable signals all comprise those originated from a semiquinone radical(g=2.0012)and superoxide radical(g11=2.041, g⊥=2.0040).The latter is shown to be bound with metal ionsespecially iron, chelated by bilirubin.The iron probably comes from bilirubin precursor---hemootobin.Active oxygen free radical scavengers may destroy these radicals.Kinetic curves of regeneration of the bilirubin radicals have been determined.Bilirubin is discussed as"active oxygen trap"in mammatians. 相似文献
234.
235.
Cyanobenzaldehydes (m-,o-,p-) were synthesized by oxidation of corresponding tolunitriles with molecular oxygen,catalyzed by cobalt acetate and sodium bromide. 相似文献
236.
237.
Discharge performance of K2FeO4 electrode under different conditions was studied by the constant electric current discharge method. The electrochemical characteristics of K2FeO4 electrode were investigated for the first time by means of cyclic voltammetry. The results show that the K2FeO4 electrode made at moderate pressure (20MPa) and discharged at lower current has better discharge performance. It is also found that K2FeO4 electrode is significantly rechargeable. 相似文献
238.
A Triton X-100-4.0G-D (4.0G-D refers to a 4.0-generation dendrimer) was brought forward as a new phosphorescence labeling reagent. Two types of specific affinity adsorption (AA) reactions (direct method and sandwich method) were carried out between the labeling product of Triton X-100-4:0G-D-Wheat germ agglutinin (WGA) and alkaline phosphatase (ALP), the product of AA reaction preserved the good characteristics of room temperature phosphorescence (RTP) of 4.0G-D and △Ip of the product was proportional to the content of ALP. According to the fact stated above, a new method for the determination of trace ALP by affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) was established on the basis of WGA labeled with the Triton X-100-4.0G-D. The detection limits were 0.20 ag·spot^-1 (corresponding concentration: 5.0×10^-16 g·mL^-1, namely 5.0×10^-18 mol·L^-1) for a direct method and 0.14 ag·spot^-1 (corresponding concentration: 3.5×10^-16 g·mL^-1, namely 3.5×10^-18 mol·L^-1) for a sandwich method, respectively. For their high sensitivity, good repeatability and high accuracy, the direct method and sandwich method have been successfully appfied to determine the content of ALP in human serum, and the results were coincided with the clinical detection results of the enzyme-linked immunosorbent assay method by the Zhangzhou Hospital of Traditional Chinese Medicine. Meanwhile, the mechanism for the determination of trace ALP by AA-SS-RTP was discussed. 相似文献
239.
Pt3Co核-Pt壳型纳米粒子的制备及磁性 总被引:1,自引:1,他引:1
Pt3Co alloy nanoparticles were prepared by the reduction of H2PtCl6 and Co(OOCCH3)2 using NaBH4 as a reducing agent. The Pt3Co core-Pt shell nanoparticles (Pt3Co@Pt) were synthesized using hydrogen absorption reduction and characterized by plasma-atomic emission spectrometry (ICP), transmission electron microscopy (TEM), X-ray diffraction (XRD) and SQUID magnetometer. The results show that average size of Pt3Co@Pt nanoparticles is 3.6 nm with a standard deviation of 0.9 nm. Heating Pt3Co nanoparticles in air at 700 ℃ for 1 h, Co in Pt3Co nanoparticles was oxidized to Co3O4 and CoO; while no oxidation tendency was detected for Pt3Co@Pt nanoparticles. The crystallize structure of Pt3Co@Pt changed from the face centered cube (fcc) to the face centered tetragonal (fct) after the heating treatment. The coercivity of the heated Pt3Co@Pt reached to 276 Oe at room temperature. 相似文献
240.
高效液相色谱法测定橡胶促进剂TBBS 总被引:3,自引:0,他引:3
采用反相高效液相色谱法(HPLC)测定了橡胶促进剂N-叔丁基-2-苯并噻唑次磺酰胺(TBBS)的纯度,标准偏差小于0.3。 相似文献