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991.
992.
LIU Fan ZHANG Ling-yi QIAN Jun-hong GAO Fang-yuan REN Jun ZHANG Wei-bing 《高等学校化学研究》2013,29(5):828-830
Proteomics is becoming more and more mature,but the detection of low abundance proteins is still a difficult task.Laser-induced fluorescence(LIF) detection is one of the most sensitive detection methods in a capillary electrophoresis(CE)system[1-3].However,most proteins do not exhibit favourable native fluorescence,a derivatization procedure is necessary for LIF detection of proteins.Since the derivatization reaction between protein and fluorescent reagent takes place after the separation of protein,the separation cannot be compromised by multiple derivatization products,the post-column derivatization becomes an attractive method for derivatization in CE-LIF system[4'5].The gap reactor,coaxial reactor and sheath flow cuvette reactor have been widely used for post-column derivatization in CE-LIF system[6].The gap reactor is constructed by aligning separation and reaction capillaries with a small gap[7,8]. 相似文献
993.
Molecular dynamics simulation was used to study the ionic liquid(IL) crystalline film based on 1-ethyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide([emim][Tf2N]) and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate([emim][TfO]) on the graphite surface. Our results show that the cations are parallelly distributed to the surface in the 1/2 monolayer(ML) crystalline film. The [Tf2N]- anions are parallel to the surface with the oxygen atoms at the bottom, whereas the [TfO]- anions are perpendicularly distributed to the surface also with the oxygen atoms at the bottom in the 1/2 ML crystalline film. It has been found that the IL-vapor interface strongly influences the arrangement of ions at the interface. The anions in the top layer with the oxygen atoms outmost turn over to make themselves with the F atoms outmost so as to form C-H···O hydrogen bonds with the cations. The calculated orientational ordering shows that in the outmost layer at the IL-vapor interface, the cation rings present either parallel or perpendicular to the surface at 350 K. 相似文献
994.
In the frame of the quark recombination model, we study the momentum distributions and cor- relations of constituent quarks in jets by analyzing the final state hadrons generated by PYTHIA for the hard parton fragmentation processes in vacuum. Parameterizations for the distributions are tabulated. 相似文献
995.
GU Zhi-Yu QIAN Shang-Wu 《理论物理通讯》2009,51(6):967-972
This paper obtains the knotted pictures of Hadamard gate and CNOT gate in terms of surgical operations described in knot theory. 相似文献
996.
The effect of DziaJoshinski-Moriya (DM) interaction on thermal entanglement of a two-qubit XXZ spin chain in a homogenous magnetic field is investigated. It is found that the DM interaction can enhance thermal entanglement. When D is large enough, the entanglement can exist for larger temperatures and strong magnetic field. 相似文献
997.
An optical readout uncooled infrared detector, employing a substrate-free focal plane array with pitch size 60μm, is established. The reflector deformation induced by the stress mismatching of the bi-layer structure is discussed and, in turn, a universal solution to determine both the optical readout sensitivity and the optimal filter position is found. By applying this solution, the optical readout sensitivity for the ideal plane reflector could theoretically increase by 80% as compared with the conventional operation, and the sensitivity loss caused by the reflector deformation can also be reduced to a reasonable level. 相似文献
998.
999.
单嘧磺隆原药组成的定性和定量分析 总被引:3,自引:0,他引:3
磺酰脲类除草剂作用于乙酰乳酸合成酶(ALS),对温血动物几乎无毒,磺酰脲活性分子必须含有胍桥,在胍桥间位须为双取代,而对位不能有任何取代基,分子中还须有一个杂环系统,前文从室内筛选出发,发现部分单一取代杂环的磺酰脲化合物也具有足够的除草活性, 相似文献
1000.
用 HB 30 0 0型磨样机制取样品 ,Spectro M8型直读光谱仪分析生铁中硅、锰和磷 ,方法可行 ,数据准确 ,取得了理想效果。 相似文献