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991.
用光谱学方法研究不同放电等离子体粒子约束 总被引:2,自引:2,他引:0
本文用光谱学方法研究在HL-1装置上LHCD及ECRH等离子体,弹丸注入等离子体,偏压电极与偏压孔栏等离子体粒子约束特性。结果表明:在弹丸注入使用正向偏压电极与偏压孔栏期间,等离子体粒子约束行到改善,较低密度下(^ne<2.0×10^1^3cm^-^3),LHCD脉冲期间粒子约束得到改善;而当密度^-ne大于2.0×10^1^3cm^-^3时,等离子体约束变坏。ECRH脉冲期间粒子约束得不到改善。 相似文献
992.
993.
Gräwert T Span I Bacher A Groll M 《Angewandte Chemie (International ed. in English)》2010,49(47):8802-8809
The biosynthesis of natural products is a treasure trove of unusual reaction mechanisms. This Minireview summarizes recent work on the structure and mechanism of IspH protein, which catalyzes the reductive dehydroxylation of an allyl alcohol in a biosynthetic pathway leading to isoprenoid precursors. 相似文献
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997.
Two open substituted benzodipyrroles were tested as hydrogen-bond-forming anion ionophores for the development of anion-selective electrodes. These compounds were incorporated in plasticized polymeric membranes with different plasticizers, using different membrane compositions to explore their response towards several anions. The electrodes constructed with membranes containing 2-nitrophenyl octyl ether and a 0.5 molar ratio ionic additive/ionophore showed pronounced anti-Hofmeister behaviour, providing a significantly enhanced response towards the divalent anions sulfate, sulfite, thiosulfate and oxalate. The selected electrodes were also evaluated in terms of detection limits and selectivity. 1H NMR experiments were carried out in an attempt to explain some aspects of the behaviour observed. 相似文献
998.
A new disposable multi-walled carbon nanotubes modified single-sided heated screen-printed carbon electrode (MWNT/ss-HSPCE) was fabricated. The electrochemical behavior of silybin was investigated by cyclic voltammetry and the probable electrode reaction mechanism was proposed. A simple and cheap direct current heating supplier was used to heating the electrode for adsorptive accumulation of silybin. The square wave voltammetric stripping peak current of silybin at MWNT/ss-HSPCE with an elevated electrode temperature of 50 °C only during accumulation step was dramatically improved compared with that at bare single-sided heated screen-printed carbon electrode (ss-HSPCE) without heating. This enhancement was mainly contributed to the combination of the advantages of multi-walled carbon nanotubes and electrically heated electrodes. Under optimum conditions, two detection linear ranges of silybin were from 1.0 × 10−9 to 1.0 × 10−7 M and 3.0 × 10−7 to 1.0 × 10−6 M. A detection limit of 5.0 × 10−10 M could be obtained (S/N = 3), which was more than two magnitudes lower than that at bare ss-HSPCE without heating. To the best of our knowledge, this was also at least two magnitudes lower than any others for electrochemical detection of silybin in the literature. Finally, the method was successfully applied to the determination of silybin in pharmaceutical tablets. 相似文献
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1000.
We report the electrochemical Li reactivity of the cubic NiP3 phase, a candidate for anode applications for Li-ion batteries. NiP3 reacts with nine lithium per formula unit leading to a first cycle reversible capacity of 1,475 mAh/g at an average potential
of 0.9 V vs. Li+/Li°. Electrochemical measurements and complementary X-ray diffraction showed that NiP3 presents a conversion process competing with an insertion process. A good cycleability may only be obtained on a limited potential window, excluding the
low-potential region.
This paper was presented at the 11th EuroConference on the Science and Technology of Ionics, Batz-sur-Mer, Sept. 9–15, 2007. 相似文献