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1.
Chenglong Yu a b Xin Hao a Hongtao Jiang a Lili Wang a a School of Materials Science Engineering Shaanxi University of Science & Technology Xi’an China b Research Laboratory of Hydrothermal Chemistry Faculty of Science Kochi University Kochi Japan 《中国颗粒学报》2011,9(1)
Fe 3 O 4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl 2 ·4H 2 O with N 2 H 4 ·H 2 O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). Face scanning energy dispersive spectrum (face scanning EDS) and two-dimensional fast Fourier transform (2DFFT) for element distribution were carried out for confirming compos... 相似文献
2.
3.
Xuexi Tie a Junji Cao b a National Center for Atmospheric Research Boulder CO USA b SKLLQG Institute of Earth Environment Chinese Academy of Sciences No. Fenghui South Road High-Tech Zone Xi’an China 《中国颗粒学报》2010,8(1)
PARTICUOLOGY regrets that the above paper was mistakenly classified as a ‘Review’ rather than an ‘Invited paper’ when originally published in volume 7, issue 6, 426–431. 相似文献
4.
W18Cr4V 总被引:2,自引:1,他引:1
The frictionand
wear characteristics of the surfa ce compound layer of W18Cr4V steel by combined treatment
of ion nitrocarburizing-ion sulphurizing were investigated. The friction coefficient of
the compound l ayer against GCr15 steel was determined witha block-ring friction tester.
The wear test was carried out with a reciprocating wear tester. The worn surface was
analyzedby scanning electron microscopy(SEM). The experimental results reveale d that the
friction coefficient was lower for treatedW18Cr4V steel against GCr1 5 steel. The wear
resistance of the compound layer was higher because the nitroc arbonide andthe sulphide in
the compound layer were capable of friction-reduct ion and adhesion-inhibition. 相似文献
5.
基于比较分子力场分析(CoMFA)方法建立21种新型三唑并噻二唑衍生物对蛋白酪氨酸磷酸酯酶1B(PTP1B)的抑制活性(pM_P)的三维定量构效关系(3D-QSAR)。训练集中17个化合物用于建立预测模型,测试集5个化合物作为模型验证。已建立的CoMFA模型的交叉验证系数(R_(cv)~2)、非交叉验证系数(R~2)分别为0. 432、0. 975,说明所建模型具有较强的稳定性和良好的预测能力。该模型中立体场、静电场贡献率依次为59. 2%、40. 8%,表明影响抑制活性(pM_P)的主要因素是取代基的空间位阻及疏水性,其次是取代基的氢键及配位作用。基于此研究结果,设计了3个具有较高抑制活性的新化合物,有待医学实验验证。 相似文献
6.
YANG Jian-Guoa PAN Fu-Youb② SHAO Hongb a 《结构化学》2005,24(11):1286-1289
1 INTRODUCTION Azole derivatives, such as the derivatives of pyra- zole, imidazole, triazole including benzotriazole, te- trazole and indole, have extensive biological activi- ties. They have become the central focus of studies of agricultural chemicals, medicines, plant growth regulating agents and so on[1, 2]. Schiff bases also constitute a good type of biologically active sub- structures. Studies on pyrazole Schiff base-type fun- gicides have been reported[3, 4]. However, some struc- … 相似文献
7.
KAN Zi-Guia b CHENG Wen-Dana? WU Dong-Shenga ZHANG Haoa GONG Ya-Jinga ZHU Jinga TONG Hua-Nana a 《结构化学》2005,24(12):1468-1475
1 INTRODUCTION stand the chemical bonding properties and electronic origins of optical transition for solid In(PO3)3, the During the past decades, many indium phosphates crystal energy band and optical response functions have been reported and researched on their conduc- are also calculated. tivity anisotropy, band structure and optical proper- ties[1, . However, to our current knowledge, the com- 2] 2 EXPERIMENTALAND pounds containing alkaline-earth metals are rarely COMPUTATIO… 相似文献
8.
1 INTRODUCTION There has been increasing interest in the re-search of diode laser-pumped solid-state lasers in re-cent years because of the rapid development of highpower diode lasers. Nd:YAG and Nd:YVO crystalsare commercially available, but limited to low Nd3 (= 1 at.%) doping concentration and to narrow ab-sorption bands near the diode emission wavelengthof 808 nm. Therefore, it is necessary to explore moreefficient crystal materials for diode-pumped solid-state lasers. The alkali … 相似文献
9.
MA Peng-Gaoa ZHANG Ming-Jiea② YANG Qi-Chaob YU Jiu-Gaoa a 《结构化学》2005,24(3):311-314
1 INTRODUCTION Mannich reaction plays an important role in theconstruction of a large variety of nitrogen-containingmolecules, for instance, some pharmaceuticals andnatural products[1, . In practice, phenols and naph- 2]thanols can serve as the substrate of Mannich reac-tion to obtain aminomethylate by the treatment withformaldehyde and amines or nitrogen heterocycliccompounds[3~5]. We report herein the synthesis andcrystal structure of a new nitrogencontaining co… 相似文献
10.
1 INTRODUCTION Since the discovery of carbon nanotubes (CNTs) by S. Iijima[1] in 1991 as a quasi-one-dimensional nano-material, extensive attention has been paid to CNTs due to their special electric conductivity, me- chanical properties and potential applications in molecular device, complex material and so on. The structures of CNTs could be described as graphite sheet with planar hexagonal network structure cur- ling into a tube having the diameter of only several nanometers. In t… 相似文献