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排序方式: 共有147条查询结果,搜索用时 15 毫秒
1.
M. Battilotti C. Colapicchioni I. Giannini F. Porcelli L. Campanella M. Cordatore F. Mazzei M. Tomassetti 《Analytica chimica acta》1989
A new type of biosensor based on the coupling of an enzyme to an ion-selective membrane containing a conducting polymer is evaluated. The results obtained with the enzyme field- effect transistor (ENFET) and the ion-selective electrode (ISE) for the determination of creatinine and urea are compared. The presence of the conducting polymer significantly lowers the detection limit for creatinine by one decade to 10?7 and 10?4 M for the ENFET and ISE, respectively. The determination of urea in urine and serum with the ENFET was carried out, and the results correlated well with those obtained by spectrophotometry. 相似文献
2.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
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用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的. 相似文献
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New, rigorous results for the tearing island saturation problem are presented. These results are valid for the realistic case where the magnetic island structure is non-symmetric about the reconnection surface and the electron temperature, on which the electrical resistivity depends, is evolved self-consistently with the island growth. 相似文献
6.
Opper AK Korkmaz E Hutcheon DA Abegg R Davis CA Finlay RW Green PW Greeniaus LG Jordan DV Niskanen JA O'Rielly GV Porcelli TA Reitzner SD Walden PL Yen S 《Physical review letters》2003,91(21):212302
The forward-backward asymmetry in np-->dpi(0), which must be zero in the center-of-mass system if charge symmetry is respected, has been measured to be [17.2+/-8.0(stat)+/-5.5(syst)]x10(-4), at an incident neutron energy of 279.5 MeV. This observable is compared to recent chiral effective field theory calculations, with implications regarding the du quark mass difference. 相似文献
7.
Porcelli TA Adamczak A Bailey JM Beer GA Douglas JL Faifman MP Fujiwara MC Huber TM Kammel P Kim SK Knowles PE Kunselman AR Maier M Markushin VE Marshall GM Mason GR Mulhauser F Olin A Petitjean C Zmeskal J;TRIUMF Muonic Hydrogen Collaboration 《Physical review letters》2001,86(17):3763-3766
Measurements of muon-catalyzed dt fusion ( d(mu)t-->4He + n + mu(-)) in solid HD have been performed. The theory describing the energy dependent resonant molecular formation rate for the reaction (mu)t + HD-->[(d(mu)t)pee](*) is compared to experimental results in a pure solid HD target. Constraints on the rates are inferred through the use of a Monte Carlo model developed specifically for the experiment. From the time-of-flight analysis of fusion events in 16 and 37 microg x cm(-2) targets, an average formation rate consistent with 0.897+/-(0.046)(stat)+/-(0.166)(syst) times the theoretical prediction was obtained. 相似文献
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The nonlinear evolution of a Hamiltonian magnetic field line reconnection in a two-dimensional fluid plasma leads to a macroscopic equilibrium with a finite-size island and fine-scale spatial structures. The latter arise from the phase mixing of the Lagrangian invariant fields. This equilibrium is the analog of the Bernstein-Greene-Kruskal equilibrium solution for electrostatic Langmuir waves. 相似文献
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利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
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