排序方式: 共有76条查询结果,搜索用时 0 毫秒
21.
<正>A new tetrahydrophenanthrene named henryin A(1) was isolated from the leaves of Chloranthus henryi.Its structure was determined to be(S)-4,6,9-trimethyl-5,6,7,8-tetrahydrophenanthrene-1,2-diol on the basis of IR,MS,1D and 2D NMR spectral. 相似文献
22.
Based on the different reactivity of stannyl and bromo groups, (Z)-α-bromovinylstannanes can undergo the cross-coupling reaction with alkynyl Grignard reagents in the presence of tetrakis(triphenylphosphine)palladium(0) catalyst in THF at room temperature to afford stereoselectively 1,3-enynylstannanes in good yields. 相似文献
23.
KOKOT Serge 《中国科学B辑(英文版)》2011,(5)
This paper describes a kinetic spectrophotometric method for simultaneous determination of three cephalosporin antibiotics,cephradine,cefaclor and cefixime,with the aid of chemometrics. The method relies on their oxidation with KMnO4 to produce green manganate with different kinetic rates in alkaline medium. The proposed method was successfully applied to a pharmacokinetic study of three cephalosporin antibiotics in rabbit plasma via intravenous injections. The results indicated that the amount of cephradin... 相似文献
24.
本文比较了一系列对羟基苯衍生物的紫外可见吸收光谱和荧光光谱的差异,以及荧光试剂与其衍生后所得衍生物荧光光谱性质的区别,研究了产生这些差异的可能原因,提出了一些可行的分析此类物质的方法,便于肿瘤患者体液的分析,以期能为确定特征性癌变标志物及早期癌症的检测提供依据。 相似文献
25.
含控制参数的抽象动力方程连值问题之积分算子求解法 总被引:2,自引:0,他引:2
讨论一类抽象Volterra型积分算子,利用此获得含控制参数的抽象动力方程边值问题的解。这种新的求解法我们称为积分算子求解法。 相似文献
26.
温度对红花抗氧化活性的影响 总被引:2,自引:0,他引:2
红花(Carthamus tinctorius L.)在100℃时。加热不同的时间2,6。15,21,30h。测定其红外漫反射光谱。图谱表明。加热可能使红花中某些化学成分的结构发生了变化。进一步比较加热前后红花水提物及乙醇提取物对超氧自由基。DPPH自由基的清除作用。结果进一步表明,加热使红花某些活性成分的结构发生了变化。而使其抗氧化活性受到较大影响。 相似文献
27.
伊红和牛血清白蛋白相互作用 总被引:1,自引:0,他引:1
运用紫外光谱法和荧光光谱法研究了伊红和牛血清白蛋白(以下简称BSA)的相互作用。结果表明,伊红是与BSA中特定部位(弱极性区域)相结合,且符合Scatchard模型。 相似文献
28.
Roger Ruan 《高等学校化学研究》2009,25(3)
The authors dealt with the effects of dynamic high pressure micro-fluidization(untreated and 20―160 MPa treated) on the structure and physico-chemical properties of egg white solutions[6%(mass fraction) or 61.2 mg protein/mL]. Micro-fluidization treatment resulted in a decrease in mean particle size,and little change in solubility. It was found that the residual denaturation enthalpy was decreased with the increase of pressure from 20 to 100 MPa and from 120 to 160 MPa,reaching into the maximum at 160 MPa. ... 相似文献
29.
Yu Lin Feng Bin Xie He Ran Li Qiong Ming Xu Xiao Juan Zhang Yue Sheng Wang Shi Lin Yang 《中国化学快报》2010,21(9):1100-1102
<正>A new sulfated triterpenoid,3β,24-dihydroxyurs-20-ene-24-O-sulphonyl-28-oic acid(fabagoin.1) was isolated from the barks of Zygophyllum fabago L.Its structure was elucidated on the basis of spectroscopic data. 相似文献
30.