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Litao Zhao Fanghong Luo Anting Wang Jing Zhang Yuanhang Wang Liangtao Zhao Zhaoyan Wang Qiaosheng Pu 《Electrophoresis》2020,41(15):1273-1279
Mutations in the potassium channel genes may be linked to the development of epilepsy and affect the blood potassium levels. Therefore, accurate determination of potassium in the blood will be critical to diagnose the cause of epilepsy. CE is a competent technique for the fast detection of multiple ions, but complicated matrices of a blood sample may cause significant variation of migration times and the peak shape. In this work, a procedure for rapid stabilization of the capillary inner surface through preflushing of a blood sample was employed. The process takes only 40 min for a capillary and then it can be used for more than 2 weeks. No pretreatment of the blood sample or other surface modification of the capillary is needed for the analysis. The RSDs of the migration time and peak area were reduced to 1.5 and 5.1% from 12.6 and 14.5%, respectively. The proposed method has been successfully applied to the determination of the potassium contents in the blood sample of patients with epilepsy at different stages. The recoveries of potassium ions in these blood samples are in a range from 86.5 to 104.5%. 相似文献
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富碳炸药在爆轰过程中可产生团簇分子,而现有的实验手段不能直接观测团簇分子的形成过程.本文采用ReaxFF/lg力场对梯恩梯(TNT)在不同温度下的热分解过程进行了模拟.研究发现:团簇分子在反应初始阶段形成缓慢,大约一次增加一个TNT相对分子质量.随着反应进行,团簇分子迅速增大,最大团簇分子相对分子质量可达8000~10000,约占体系质量的18%.分析团簇分子的结构发现,团簇分子中一部分苯环被破坏,形成五元环和夹杂N、O原子的六元环,在3500 K条件下还形成了更为复杂的七元环等结构.通过体积膨胀和直接降温的方法,研究了团簇分子的稳定性:体积膨胀使得团簇分子迅速分解;而直接降温,团簇分子又聚合成更大的团簇.分析类石墨结构的产生过程,发现先膨胀然后降温是必不可少的步骤.比较团簇分子和TNT分子中各原子质量所占比,团簇分子中C原子质量比始终在增加. 相似文献
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Bin Qi Min Hu Zhongming Chen Kesheng Shao Yuanhang Zhang Xiaoyan Tang 《中国科学:化学(英文版)》2001,44(1):74-79
HPLC along with FT-IR technique was used to study the formation of organic peroxides in the Cl2-ethane-air photoreaction system. Ethyl hydroperoxide (CH3CH21OOH, EHP) and peroxyacetic acid ( CH3C(O)OOH, PAA) were conformed to be the peroxide product in the reaction system. In addition, methyl hydroperoxide (CH3OOH, hydroxymethyl hydroperoxide (HOCH2OOH, HMHP) and two unidentified organic peroxides were detected for the first time. EHP and were the dominant peroxide products. The identification of HMHP showed that Criegee biradical CH2OO may be formed as an intermediate in the oxidation of ethane. Simulation results showed that photooxidation of ethane may make substantial contribution to source of organic peroxides in the atmosphere. 相似文献
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Luo Laichun Wang Qiang Xiang Yuanhang Peng Xiaozhi Hu Chunling 《Chemistry of Heterocyclic Compounds》2021,57(12):1220-1229
Chemistry of Heterocyclic Compounds - A series of novel thiazolo[4,5-d]pyrimidin-7(6H)-ones were designed, synthesized, and evaluated as anticancer agents. Among them, two compounds demonstrated... 相似文献
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Aseries of Ni catalysts supported on alumina with different Ce contents(1.0%-6.0%, mass fraction) was prepared by the impregnation method and used for dry reforming of methane(DRM) at a relatively low temperature of 650 oC. The promotion effect of Ce with different loading amounts on the physicochemical properties of the catalysts was systematically characterized by transmission electron microscopy(TEM), X-ray diffraction(XRD), N2 adsorption-desorption, thermo elemental IRIS Intrepid inductively coupled plasma atomic emission spectrometer (ICP-AES), UV-visible diffuse reflectance spectroscopy(UV-Vis DRS), Fourier transformation infrared(FTIR) spectra, H2-temperature programmed reduction(H2-TPR) analysis, H2-temperature programmed desorption(H2-TPD), and the X-ray photoelectron spectroscopy(XPS) techniques. The results indicate that all the catalysts mainly exist in the NiAl2O4 phase after being calcined at 750 oC with small Ni particle sizes due to the strong metal-support interaction derived from the reduction of the NiAl2O4 phase. The Ce-promoted catalysts show better catalytic performance as well as the resistance against sintering of Ni particles and deposition of carbon compared to the Ni/Al2O3 catalyst. The Ni-6Ce/Al2O3 exhibits the best catalytic stability and coke resistance among the four catalysts studied, which is due to its small Ni nanoparticles sizes, excellent reducibility as well as high amount of active oxygen species. In a 400 h stability test for DRM reaction at 650 oC, Ni-6Ce/Al2O3 exhibits less coke deposition and small growth of Ni nanoparticles. This work provides a simple way to preparing the Ni-Ce/Al2O3 catalyst with enhanced catalytic performance in DRM. The Ni-6Ce/Al2O3 catalyst has great potential for industrial application due to its anti-sintering ability and resistance to carbon deposition. 相似文献
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Yichen Hu Yuanhang Ren Gangfeng Tang Cheng Wang Min Tang Bin Yue Heyong He 《中国化学》2014,32(11):1151-1156
TiO2 nanosheets with dominant {001} facets, coupled with Cs2.5H0.5PW12O40, were successfully synthesized by a one‐step hydrothermal reaction. The photocatalytic activity of nanocatalysts was evaluated by the degradation of Rhodamine B under UV light irradiation. The results showed that both the addition of Cs2.5H0.5PW12O40 and the exposed {001} facets of TiO2 have a positive effect on the photocatalytic activity. The improved photoactivity of nanocomposites in comparison with that of TiO2 nanosheets could be attributed to the synergistic effect between Cs2.5H0.5PW12O40 and TiO2 which facilitates the separation of photo‐induced hole‐electron pairs. 相似文献
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We have calculated the multiphoton absorption cross-sections for three expanded porphyrin derivatives using the sum-over-states-involved tensor approach in combination with the strongly correlated multireference determinant single- and double-configuration interaction method. The calculated results showed that the two- and three-photon energies corresponding to the first peak of the multiphoton absorption spectra showed a decrease (red-shifted) with the number of inserted thiophene groups, whereas the cross sections showed a remarkable increase, particularly for three-photon absorption cross-section. However, the larger twist of the molecular plane for the expanded molecule resulted in an obvious drop in the increasing trend for three-photon absorption cross-section. 相似文献
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Organic-inorganic hybrids assembled by bis(undecatungstophosphate) lanthanates and dinuclear copper(II)-oxalate complexes 总被引:1,自引:0,他引:1
Cao J Liu S Cao R Xie L Ren Y Gao C Xu L 《Dalton transactions (Cambridge, England : 2003)》2008,(1):115-120
A series of organic-inorganic hybrid compounds, K2H7[{Ln(PW11O39)2}{Cu2(bpy)2(mu-ox)}].xH2O (Ln = La, x approximately = 18 (1); Ln = Pr, x approximately = 18(2); Ln = Eu, x approximately = 16(3); Ln = Gd, x approximately 22(4); Ln = Yb, x approximately = 19 (5); bpy = 2,2'-bipyridine and ox = oxalate), have been isolated by the conventional solution method. Single-crystal X-ray diffraction studies reveal that compounds 1-5 are isomorphic and consist of one-dimensional chains, which are constructed by alternating bis(undecatungstophosphate) lanthanates [Ln(PW11O39)2](11-) and dinuclear copper(II)-oxalate complexes [Cu2(bpy)2(mu-ox)]2+.pi-pi interactions of the bpy ligands from adjacent chains lead to their three-dimensional structures. An analogue of potassium K2H9[{K(PW11O39)2}{Cu2(bpy)2(mu-ox)}1].approximately 20.5H2O(6) has also been obtained. The syntheses and structures of these compounds are reported here. Magnetic properties of 1, 2 and 3 are discussed as well. Attempts to crystallize similar compounds containing Co(II) and Ni(II) were unsuccessful. 相似文献
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Two compounds, namely [Cd(HINA)2(µ2‐H2O)(H2O)2]2[SiW12O40]·6H2O ( 1 ) and [Co(HINA)3(H2O)3][Co(HINA)2(H2O)4][SiW12O40]·2H2O ( 2 ), have been synthesized from the aqueous mixture containing H4SiW12O40, isonicotinic acid (HINA), and M(CH3COO)2 (M=Cd and Co). The compounds have been characterized by elemental analysis, IR spectroscopy, TG analysis, and single‐crystal X‐ray diffraction. The dinuclear coordinated cadmium units in compound 1 are linked to form 2D layer parallel to ab plane through π‐π interactions and hydrogen bonds. Compound 2 contains two different types of coordinated metal cations, [Co(HINA)3(H2O)3]2+ and [Co(HINA)2(H2O)4]2+, which construct 2D layer along bc plane through π‐π interactions and hydrogen bonds. In both compounds, the Keggin anions are located inside the channels and cavities formed from stack of the coordinated metal cations, which further achieve the 3D supramolecular structure through hydrogen bonds. The luminescent property of compounds 1 and 2 has been investigated. 相似文献