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81.
The interaction of Methylthymol Blue(MTB)-Zinc(Ⅱ) compound and Alizarin Red S(ARS)-Aluminum(Ⅲ) compound with Bovine serum albumin (BSA) was investigated by UV-Vis spectrophotometric method in acidic buffer solution. MTB-Zn(Ⅱ)-BSA was a blue color compound, which possesses maximum absorption at 613 nm with 172 nm, 174 nm and 18 nm of red shift compared to the MTB, MTB-BSA and MTB-Zn(Ⅱ) complexes respectively. Dual wavelength substantial amount ratio method, balance dialysis substantial amount ratio method and unity wavelength substantial amount ratio method were compared. The following results were obtained: the apparent molar absorptivity of MTB-Zn(Ⅱ) with BSA was ε=2.20×104 L·mol-1·cm-1. Conditional proportion were defined, nMTB∶nZn(Ⅱ)∶nBSA=2∶2∶1; condition combination constant, K=2.07×1010. Combination proportion were defined, nARS∶nAl(Ⅲ)∶nBSA=6∶4∶1. Condition equilibrium constant of reaction of ARS-Al(Ⅲ) with BSA was K=8.80×108. The apparent molar absorptivity of ε=2.65×104 L·mol-1·cm-1. It is suggested that combination between BSA and MTB-Zn(Ⅲ) is due to coordination force. That combination between BSA and ARS-Al(Ⅲ) is due to the coordination bond and electrostatic force. 相似文献
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HongBingJI DuGuiHE JunSONG YuQIAN 《中国化学快报》2004,15(10):1241-1244
Clean liquid oxidation of aldehydes can be accomplished using solid catalyst in the presence of molecular oxygen at room temperature, which is a valuable alternative to traditional counterparts. 相似文献
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新型杂多配合物K3H2[GeW8Mo3VO40]·4H2O的合成与晶体结构 总被引:1,自引:0,他引:1
用分步酸化、分步加料法合成出新型杂多配合物K3H2[GeW8Mo3VO40]·4H2O,并用X射线单晶衍射法测定其晶体结构,该晶体属单斜晶系,C2空间群,a=1.894 4(4)nm,b=3.292 0(7)nm,c=1.249 4(2)nm,β=90.25(3)°,V=7.792(4)nm3,Z=6.最终偏差因子R=0.063.RW=0.067. 相似文献
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The alum-borneol nanoemulsion(ABN), which combines the mineral medicine alum and the botanical medicine borneol, has been applied for approximately 40 years in the clinical treatment of burns, scalds, radiation dermatitis and shingles, and has a good curative effect. However, the current formula and dosage form of ABN pose problems of low borneol content and ease of precipitation, which greatly affects the efficacy of the drug. In this study, polyvinylpyrrolidone(PVP) was selected as a carrier mixed with different proportions of alum and borneol to produce alum-borneol-PVP fibers(ABPF) by electrospinning. The results showed that the stable system with good drug dispersion was 2:3(alum:borneol). The dissolution content of borneol from the ABPF was about 80% in 4 h, which was much higher than that of the alum-borneol liquid(ABL) and ABN. The ABPF membrane showed a more significant inhibitory effect on Staphylococcus aureus than the ABL and ABN. The composite fiber markedly increased the drug content of borneol, which was 800 times of that in ABN. The fiber had a higher solubility than the nanoemulsion in vitro, which is of great importance for the de-velopment of new forms for the clinical application of alum and borneol. 相似文献
90.
李萨如图形在检测系统中的应用 总被引:5,自引:0,他引:5
李萨如图形可以检测两个相同频率信号的相位差.主要论述具有惯性质量、弹簧和阻尼器的二阶加速度测量系统,其动态响应特性的分析方法,如何利用李萨如图形来检测力平衡式加速度传感器的动态特性,即幅频特性和相频特性,从而确定传感器的固有频率ω_n和阻尼比ξ,以此来评定传感器的综合特性. 相似文献