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排序方式: 共有210条查询结果,搜索用时 15 毫秒
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Wei SUN Dan Dan WANG Rui Fang GAO Jian SUN Kui JIAO 《中国化学快报》2006,17(12):1589-1591
In recent years the direct electron transfer of redox protein on electrode surface has attracted great attentions1. Different kind of modified electrode and various supporting films for immobilization of proteins had been proposed. But most of them are ba… 相似文献
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An HPLC post column chemical derivatization procedure based on the interaction between an acridinium triflate and amines to form highly colored derivatives on-line is described for the determination of aromatic amines. Benzocaine and butesin, local anesthetic agents that contain the aromatic amine group, were used as model compounds. Reversed-phase HPLC conditions were developed for both the separation of analytes and the reaction between analytes and the acridinium triflate in the system. Three-dimensional knitted teflon shape coils and the internal diameter and length of the coils were important parameters in reducing band broadening and background noise.N-Methyl-9-chloroacridinium triflate was shown to be applicable to the determination of primary aromatic amines, selected secondary aromatic amines, hydrazides, and hydrazines. Application of the on-line chemical derivatization procedure to the analysis of pharmaceutical dosage forms containing procainamide (primary aromatic amine), isoniazid (hydrazide), and hydralazine (hydrazine) is also described. 相似文献
4.
Kyeong‐Ryoon Lee Sung Heum Choi Jin‐Sook Song Hyewon Seo Yoon‐Jee Chae Hwang Eui Cho Jin Hee Ahn Sung‐Hoon Ahn Myung Ae Bae 《Biomedical chromatography : BMC》2013,27(7):846-852
In this study, we developed a method for the determination of PF‐04620110 (2‐{(1r,4r)‐4‐[4‐(4‐amino‐5‐oxo‐7,8‐dihydropyrimido[5,4‐f][1,4]oxazepin‐6(5H)‐yl)phenyl]cyclohexyl}acetic acid), a novel diacylglycerol acyltransferase 1 (DGAT‐1) inhibitor, in rat plasma and validated it using liquid chromatography–tandem mass spectrometry (LC‐MS/MS). Rat plasma samples were processed following a protein precipitation method by using acetonitrile and were then injected into an LC‐MS/MS system for quantification. PF‐04620110 and imipramine (internal standard) were separated using a Hypersil Gold C18 column, with a mixture of acetonitrile and 10 mm ammonium formate (90:10, v/v) as the mobile phase. The ion transitions monitored in positive‐ion mode [M + H]+ of multiple‐reaction monitoring were m/z 397.0 → 260.2 for PF‐04620110 and m/z 280.8 → 86.0 for imipramine. The detector response was specific and linear for PF‐04620110 at concentrations within the range 0.05–50 µg/mL and the signal‐to‐noise ratios for the samples were ≥10. The intra‐ and inter‐day precision and accuracy of the method matched the acceptance criteria for assay validation. PF‐04620110 was stable under various processing and/or handling conditions. PF‐04620110 concentrations in the rat plasma samples could be measured up to 24 h after intravenous or oral administration of PF‐04620110, suggesting that the assay is useful for pharmacokinetic studies in rats. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
5.
Aziza Rezig 《代数通讯》2018,46(3):1344-1352
A group is called (PF)L if the subgroups generated by its elements having same order (finite or infinite) are polycyclic-by-finite. In the present paper we prove that a group is locally graded minimal non-((PF)L∪(𝔓𝔉)𝔄) if, and only if, it is non-perfect minimal non-FC, where (𝔓𝔉)𝔄 denotes the class of (polycyclic-by-finite)-by-abelian groups. We prove also that a group of infinite rank whose proper subgroups of infinite rank are in ((PF)L∪(𝔓𝔉)𝔄) is itself in ((PF)L∪(𝔓𝔉)𝔄) provided that it is locally (soluble-by-finite) without simple homomorphic images of infinite rank. Our last result concerns groups that satisfy the minimal condition on non-((PF)L∪(𝔓𝔉)𝔄)-subgroups. 相似文献
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以1-丁基-3-甲基咪唑六氟磷酸盐离子液体[BMIM]PF6既作为溶剂又作为支持电介质, 通过恒电流、循环伏安等方法制备聚(3-溴噻吩)(PBrT)膜. 采用红外光谱(FT-IR)和扫描电子显微镜(SEM)对PBrT膜的结构和形貌进行表征, 用热重和差热分析法(TG-DTA)研究聚合膜的热稳定性, 并利用紫外-可见光谱(UV-Vis)、计时电流和计时吸收曲线研究该聚合膜电化学和电致变色的特性. 研究结果表明, 与传统方法比较, 在离子液体[BMIM]PF6中制备的PBrT膜更致密、光滑, 具有良好的氧化还原可逆性和充放电能力, 电活性高, 热稳定性好. 以该方法制备的PBrT膜颜色变化明显, 响应时间快(0.5 s), 同时由于离子液体具有电位窗宽、导电率高、可循环利用等优点, 因此在电化学聚合等方面具有良好的应用前景. 相似文献
7.
基于计算流体力学(CFD)理论,研究了不同曲率半径的螺旋导流片的托卡马克真空室内线圈水冷管道接头。利用湍流数值模拟方法,分析了线圈管道接头导流片曲率半径比、冷却水入口流速对线圈管道内流体平均雷诺数分布的影响。结果表明,不同导流片曲率半径比的线圈管道内的流体雷诺数分布曲线相似,平均雷诺数随入口流速的增加而增大,管道接头出口雷诺数随导流片曲率半径比的增大而减小,导流片曲率半径比小的管接头更适用于线圈水冷曲线管的二次流强化。此外,还为导流片曲率半径比为0.2的管接头拟合了管接头出口雷诺数与入口流速的关系式,为进一步研究类似于托卡马克真空室内线圈管道的曲线管接头的二次流强化提供理论基础。 相似文献
8.
YBCO线圈的交流损耗直接关系到YBCO设备的运行成本及稳定性。实现对YBCO线圈交流损耗的快速、准确测量,对于开展YBCO涂层导体的应用研究具有重要的意义。文中采用电测量法,在77K、零场和不同频率条件下,对YBCO线圈通以不同运行电流时产生的交流传输损耗进行测量。构建了YBCO线圈交流损耗的数值计算模型,对YBCO线圈交流损耗进行理论研究,最后将实验数据与理论计算结果进行比较,两者结果基本一致。可以发现,YBCO线圈在频率低于75Hz时,交流传输损耗随频率的增大而减小,当频率从75Hz增加到195Hz时,交流传输损耗随频率的增大而增加。 相似文献
9.
亥姆霍兹线圈磁场的均匀性分析 总被引:20,自引:8,他引:20
引入磁场均匀度的概念,对亥姆霍兹线圈磁场的均匀性进行了定量分析,并通过计算机模拟,得出了同一精度下,形成亥姆霍兹线圈均匀磁场的最佳条件. 相似文献
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