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131.
A novel sensitive method for the determination of nucleic acid (DNA) using the resonance light scattering (RLS) spectra of pentamethoxyl red has been developed. It is based on the effects on the resonance light scattering of Pentamethoxyl Red. The effective factors and the optimum conditions were studied, and the enhanced intensity of RLS is in proportion to the concentration of nucleic acids in the range of 0–2.54 µg mL−1 for ct-DNA, 0–4.54 µg mL−1 for hs-DNA. The limits of detection are 1.1 and 2.1 ng mL−1, respectively. Most foreign substances do not interfere in the determination, and the method has good selectivity and high sensitivity. It has been applied to the determination of DNA in synthetic samples and in real samples with satisfactory results. 相似文献
132.
133.
Kai Yang Xuan Zhang Enqin Fu Jingui Qin Minoru Kinoshita 《Journal of solid state chemistry》2004,177(11):4300-4304
Two new intercalation compounds were prepared by the reactions of Ni(II) cyclopolyamine complex cations with a preintercalate Mn1−xPS3K2x(H2O)y, respectively, through “ion exchange” process. Their structures were characterized by elemental analysis, X-ray powder diffraction and infrared spectroscopy. The lattice spacing increased 0.567 and 1.093 nm with respect to the pristine MnPS3. Ferrimagnetism of the intercalates was confirmed by SQUID experiment with Tc at 40 and 33 K, respectively. 相似文献
134.
A new catalytic kinetic spectrophotometric method has been developed for the determination of trace amount of manganese (II) in nonionic microemulsion medium. The method is based on the catalytic effect of manganese (II) on the oxidation of dahlia violet by potassium periodate with nitrilotriacetic acid as an activitor in the presence of nonionic microemulsion. Under the optimum conditions, the calibration graph is linear in the range of 0.0004-0.0056 μg ml−1 of manganese (II) at 580 nm. The detection limit achieved is 3.75×10−5 μg ml−1. Manganese (II) in foodstuff samples was determined with satisfactory results. 相似文献
135.
A chemically bonded cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phase (CSP) was prepared by a radical polymerization reaction. The prepared CSP was packed into fused-silica capillaries with inner diameter of 75 microm to perform enantiomer separations in CEC. The electrochromatographic behavior of the CSP was investigated. On the prepared CSP, high EOF could be generated under acidic mobile phases, which represented an advantage for the separation of acidic enantiomers. Several neutral, acidic, and basic enantiomers were resolved on the prepared CSP under aqueous mobile phases. The column efficiencies were between 20,000 and 100,000 plates/m, which were much higher than those of HPLC. In addition, it was observed that the separation of some enantiomers benefited from the adoption of THF as mobile phase modifier. 相似文献
136.
A second-order nonlinear optical polyurethane was formed with an X-type multi-dimensional charge-transfer (CT) chromophore (DNPIPDHPI) and 3,3′-dimethoxy-4,4′-diphenyl diisocyanate. Simultaneous poling and polymerization and in situ second harmonic generation (SHG) measurement technique was carried on to evaluate the thermal stability of the poling induced orientation. The SHG signal of the poled polymer film was not decay below 150 °C and remains 90% of relative d33 value at 200 °C, which is better than the results reported in literature. Comparison of thermal stability indicates that the X-type chromophores possess better property in controlling the decay of the SHG activity than classic chromophores. 相似文献
137.
Two (1,3,4)-oxadiazole ligands have been prepared. In one case the oxadiazole ring is flanked by two o-aniline groups, and in the other case it is an extension of the first where the amines are condensed with 2-picolyl groups. A monometallic copper(II) complex of the former has been prepared, and its crystal structure was determined. A number of bimetallic copper(II), cobalt(II), and nickel(II) complexes of the di-deprotonated latter ligand were prepared and isolated. The crystal structure of the cobalt(II) complex bearing two acetate bridges is reported. The work demonstrates that the seldom-employed oxadiazole ring can be used effectively for generating bimetallic complexes. 相似文献
138.
本文提出了一个硫酸中间盐子循环用以代替分解水制氢的KNO_3-I_2混合循环中的电解反应,从而使原混合循环变为一个纯热化学循环。 相似文献
139.
微量热法研究γ-Mo2N催化剂表面氢的微分吸附热 总被引:1,自引:0,他引:1
Differential heats of H 2 adsorption on γ-Mo2N catalysts were studied by using microcalorimetry. Samples with high and medium surface areas (90 and 17 m2•g -1 ) present a homogeneous energetic distribution of surface sites, which corresponds with the preferential orientation of their (200) planes. Molybdenum nitride with low surface area (8 m2•g -1 ) displays a heterogeneous energetic distribution of H 2 adsorption sites. The higher initial differential heat of hydrogen adsorption observed for the low surface Mo nitride was attributed to species adsorbed on surface sites associated with the (111) plane. 相似文献
140.
文中采用机械合金化(MA)和氢化燃烧法(HCS)制备了Mg1.9Al0.1Ni,通过对它们储氢性能的对比研究发现,MA优于HCS.采用MA制得的Mg1.9Al0.1Ni储氢合金具有较高的活性和高储氢量,对PCT结果进行计算,得出温度和氢平衡压的关系式.Mg1.9Al0.1Ni(MA)553K时100s内吸放氢量分别为2.67和2.54 mass%H.用XRD方法进行物相分析,表明添加适量Al没有改变Mg2Ni的物相结构,由于MA能够制备出纳米晶粒,使得Mg1.9Al0.1Ni合金具有更好的储放氢动力学性能. 相似文献