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521.
银在浸出黄铜矿中的催化作用 总被引:2,自引:0,他引:2
本文研究了用Fe_2(SO_4)_3、MnO_2、FeCl_3、CuCl_2等浸出黄铜矿时Ag~ 的作用。Ag~ 在氯化物溶液中不起催化作用。但在酸性Fe_2(SO_4)_3及MnO_2溶液中可使反应速率常数提高200倍,文中导出了在Ag~ 催化作用下硫酸高铁浸出黄铜矿的动力学方程。确定了速率控制步骤是离子通过产物硫层的扩散过程,活化能为35.7kJ/mol。探讨了银催化浸出黄铜矿的反应机理。 相似文献
522.
523.
Introduction As developing high-energy, low toxicity and envi-ronment friendly primary explosive has been becoming a new and important investigation field, much attention has been paid to nitrogen-rich potassium coordination compounds for the sake of their low toxicity and little pollutions.1-11 In order to make good use of potassium compounds, the reaction of 2,4-dinitrophenol (DNP) and potassium hydroxide was designed, and the title compound potassium 2,4-dinitrophenate (KDNP) was obtained… 相似文献
524.
Chengdu Liang Hui Peng Lihua Nie Shouzhuo Yao 《Analytical and bioanalytical chemistry》2000,367(6):551-555
A novel molecularly imprinted polymer (MIP) coated bulk acoustic wave (BAW) sensor was fabricated for liquid phases. It can be used as a sensitive portable implement for the assay of 2,4-dichlorophenoxyacetic acid. A logarithmic response relationship between 2.0 × 10–7 M and 5.0 × 10–4 M was found. The detection limit was 1.0 × 10–7 M. Recoveries were 93.2–108.7%. Influencing factors were investigated in detail and optimized. 相似文献
525.
Yi ZHOU Guo Lin ZHANG* Bo Gang LI Yao Zu CHEN Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Chemistry Department Zhejiang University Hangzhou National Key Laboratory of Applied Organic Chemistry Lanzhou 《中国化学快报》2001,(4)
Melanosciadum pimpinelloideum H. Boiss (Umbelliferae), an indigenous plant,is the unique representative of species Melanosciadum1. Anomalin and 3(-angeloyl-4(-hydroxy-trans-khellactone were isolated from this plant2. In this investigation, from the whole plants two new compounds, melanochromone 1 and 2-ethoxyl-2-(4-hydroxyphenyl)ethanol 2 were isolated with known compounds 1-(4-hydroxyphenyl)-1,2-ethanediol 33, tymine (5-methyluracil) 44, cimifugin 55, umtatin 65, bergenin 76, daucosterol 87… 相似文献
526.
ZHU Jun ZHU Bo QU JianYing GOU QingQuan & CHEN Fang College of Physical Science Technology Sichuan University Chengdu China Southwest Jiaotong University-Emei Campus Emei 《中国科学G辑(英文版)》2009,52(7):1039-1042
The elastic and thermodynamic properties of Zirconium carbide (ZrC) are investigated by ab initio plane-wave pseudopotential density function theory method. The obtained lattice constant, elastic constant and bulk modulus
B are consistent with the experimental and theoretical data. Through the quasi-harmonic Debye model, the dependences of the
normalized volume V/V
0 and the bulk modulus B on pressure P, as well as the specific heat C
V
on the temperature T are obtained successfully. The relationships of the thermal expansion α with temperature and pressure are also investigated, which indicate the temperature hardly has any effect on the thermal
expansion α at high pressure.
Supported by the National Natural Science Foundation of China (Grant No. 10776022) 相似文献
527.
Shui Hua TANG Bao Chun LIU Qi LIANG Li Zhen GAO Liang Fu ZHANG Zuo Long YU* Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 《中国化学快报》2001,(1)
It is well known that NO is one of the most predominant pollutants. It is the main source of acid rain and has strong carcinogenicity. Therefore, removal of NO is one of the key environmental subjects in the world nowadays. With the discovery of carbon nanotubes and their large-scale synthesis1-2, attention is now being focused on their potential application in various fields of materials research. In the field of heterogeneous catalysis, numerous carbon materials have been used to disperse … 相似文献
528.
考虑带调和势的超临界非线性Schrdinger方程,解决了该方程整体解和爆破解存在所依赖的初始条件的最佳分界门槛.通过构造两类强制变分问题和建立局部不变半流,运用势井方法和凹方法,获得了该方程在两个不同的空间中的整体解和爆破解的最佳门槛条件. 相似文献
529.
PAN Min HUANG Zheng MA HuanFeng QIANG WeiRong WEI LianFu WANG Long & ZHAO Yong Key Laboratory of Magnetic Levitation Technologies Maglev Trains Superconductivity R&D Center Southwest Jiaotong University Chengdu China School of Physical Science Technology Superconductivity Research Group School of Materials Science Engineering University of New South Wale Sydney ... 《中国科学G辑(英文版)》2009,(7)
The lattice parameters, band structure, density of state and elastic constant of RE-doped CeO2 (RE=Sm, Gd, Dy), the buffer material for coated HTS conductors, are calculated using the plane-wave method with pseudopotentials based on the density functional theory (DFT) of first-principle. The rule and mechanism of the effect of rare earth impurity on the critical thickness of the CeO2 buffer layer are investigated. It is found that, in the range of the calculation, the changes of the lattice volume V and ela... 相似文献
530.
本文讨论了连续Domain D的极大点Max(D)的紧子集Com(Max(D))与凸幂Domain CD的极大点Max(CD)一一对应的条件以及Max(CD)上拓扑的性质, 证明了当X为局部紧Hausdorff空间时,X的上空间UX的凸幂Domain C(UX)的极大点Max(C(UX))与Com(Max(UX))(即X的紧子集)一一对应.X的上空间UX上的Lawson拓扑与X紧子集上的Vietoris拓扑相同,并且与Max(C(UX))带有C(UX)上的相对Scott拓扑同胚. 相似文献