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101.
采用喷雾干燥-高温固相法制备纳米LiFePO4与LiFePO4/C正极材料,用X-射线衍射,扫描电镜等对合成材料进行了表征,并对以LiFePO4为正极的电池进行了电化学性能测试。结果表明:材料合成最佳煅烧温度为600 ℃;合成过程中由于碳对LiFePO4晶型的生长有一定的抑制作用,相对于纯LiFePO4材料,LiFePO4/C材料粒径更小;并且,在此最佳合成温度下合成的LiF  相似文献   
102.
This paper describes a convenient method for the extraction and detection of eight anti-ulcer drugs simultaneously in horse urine, a relatively complex and viscous matrix, using a single-step liquid-liquid extraction followed by high-performance liquid chromatography – mass spectrometry (LC-MS). Anti-ulcer drugs were isolated from horse urine by salting out and liquid-liquid extraction. Detection of these drugs at concentrations below 1 ng mL?1 could be achieved using LC-MS-MS in the positive atmospheric pressure chemical ionisation (APCI) mode. The above analysis was also extended to elimination studies of horses administered with ranitidine and omeprazole. The urinary elimination data of these two drugs suggest that ranitidine was eliminated from horse urine at a much slower rate than omeprazole. In addition, three ranitidine metabolites and six omeprazole metabolites were identified for the first time in equine urine samples.  相似文献   
103.
Pt对Mo基催化剂还原-硫化过程的影响   总被引:2,自引:0,他引:2  
采用脉冲硫化、连续硫化、程序升温还原、程序升温及程序降温电导及X射线衍射等方法研究了贵金属Pt对MoO3催化剂还原-流化过程的影响及Pt对MOS2配位不饱和活性中心形成的影响.结果表明,Pt担载或在MoO3上可以促进MoO3的还原-硫化,使MoO3的还原-硫化温度大大降低Pt担载在MoSw上可促进MoS2的部分还原形成配位不饱和的钼中心  相似文献   
104.
以[Fe(CN)4(bipy)]2-为建筑块和[Ni(pn)2]2+在水溶液中反应,合成了{[Ni(pn)2][Fe(CN)4(bipy)]}2·3H2O(pn=1,3-丙二胺)。通过X-射线单晶衍射确定了其晶体结构。该配合物属单斜晶系,P21/n空间群,晶胞参数为:a  相似文献   
105.
任飞  李秋小 《催化学报》2007,28(9):829-834
以水合肼和硼氢化钾为共还原剂制备了四元合金催化剂Ni-Cu-Co-La,并将其应用于乙腈催化加氢反应.采用X射线衍射、X射线光电子能谱、透射电镜和H2程序升温脱附对催化剂进行了表征,考察了催化剂组分对乙腈选择性加氢制乙胺催化性能的影响.结果表明,Cu,Co和La的加入均不同程度地提高了催化剂的活性和选择性,在反应压力1.8 MPa,反应温度120℃,反应时间1 h的条件下,乙腈转化率和乙胺选择性分别为100%和98.24%,优于使用Raney Ni、非晶态Ni-B和Co-B合金催化剂时的结果.  相似文献   
106.
利用磁场诱导的微粒运动即磁泳对磁响应性粒子进行精细分离,是近年来发展起来的选择性分离细胞和高分子量核酸的有效技术。本文在阐明磁泳分离原理的基础上,介绍了磁泳分离的分流薄层分级技术、四极磁场流动分离技术和微芯片上的自由流磁泳分离技术的装置构造、工作原理及其在生物分离分析中的应用。  相似文献   
107.
A vacuum ultraviolet photoionization mass spectrometric study of acetone   总被引:1,自引:0,他引:1  
The photoionization and dissociative photoionization of acetone have been studied at the photon energy range of 8-20 eV. Photoionization efficiency spectra for ions CH3COCH3+, CH3+, C2H3+, C3H3+, C3H5+, CH(2-)CO+, CH3CO+, C3H4O+, and CH3COCH2+ have been measured. In addition, the energetics of the dissociative photoionization has been examined by ab initio Gaussian-3 (G3) calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. With the help of G3 results, the dissociation channels for the formation of the fragment ions CH3CO+, CH2CO+, CH3+, C3H3+, and CH3COCH2+ have been established. The G3 results are in fair to excellent agreement with the experimental data.  相似文献   
108.
Structure of thiocyanate adlayers on Rh(111): an in situ STM study   总被引:1,自引:0,他引:1  
In situ scanning tunneling microscopy (STM) was used to examine the structure of thiocyanate adlayers specifically adsorbed on Rh(111) in solutions of potassium hydroxide and perchloric acid, both containing potassium thiocyanate (KSCN). An atomically flat terrace-step structure was consistently observed on Rh(111) surfaces prepared by the flame-annealing-quenching method. The Rh(111)-(1 × 1) atomic structure was discerned on the atomically flat terrace even in the alkaline solution. High-resolution STM images disclosed two different structures of the SCN adlayers, () and (2 × 2), in the alkaline and the acidic media, respectively. In each structure, an individual adsorbed SCN ion appeared as a single spot with a constant corrugation height in STM images, suggesting that SCN ions adsorbed predominantly with their S-ends at particular bonding sites on Rh(111). The difference in the adlayer structure in the two solutions can be attributed to the interaction between adsorbed SCN and coadsorbed K+ in the alkaline solution, and is different from that between adsorbed SCN and H+ in the acidic solution. Received: 26 February 1997 / Accepted: 3 March 1997  相似文献   
109.
A method is proposed to calculate molar conductivity based on mode coupling theory in which the ion transference number is introduced into the theory. The molar conductivities of LiPF6, LiClO4, LiBF4, LiAsF6 in PC (propylene carbonate) are calculated based on this method. The results fit well to the literature data. This presents a potential way to calculate the conductivities of Li-ion battery electrolytes.  相似文献   
110.
INTRODUCTIONAdsorption has been considered to be the best available technology for removing organics from water in the USSafe Drinking Water Act[1]. Due to many drawbacks of activated carbon[2-7], the most widely used adsorbent,hypercrosslinked polymeric adsorbents developed by Tsyurupa and Davankov[8] have been increasingly viewedas an alternative to activated carbon for selective removal of specific organic substances from contaminatedwater[9-12], and series of researches have been do…  相似文献   
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