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101.
Zhiyuan Chang Lijun Diao Songsheng Jiang Anli Li Min Zhao 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(1):61-68
Vezetéknév
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
102.
硒对慢性活动性肝炎的影响 总被引:2,自引:0,他引:2
50例慢性活动性肝炎(慢活肝)随机分为治疗组和对照组。25例治疗组接受12周补硒治疗,结果显示,治疗组与对照组比较,血清ALT显著下降,谷胱甘肽过氧化物酶活力明显升高,提示补硒能防治自由基引起的肝损伤,防止慢性肝病的发展。 相似文献
103.
Zhe Jiang Shengbao Diao Ren Li Wei Zhou Jinfeng Sun Yi Zhou 《Natural product research》2018,32(9):1017-1021
A new 1,4-napthoquinone derivative, namely (S)-(-)-3-(8-hydroxy-1,4-dioxo-1,4-dihydro-naphthalen-2-yl)-3-(4-hydroxy-3-methoxyphenyl)-propionic acid methyl ester (1), was isolated from the roots of Juglans mandshurica Maxim. The structure was identified based on HR-ESI-MS, 1D and 2D NMR spectroscopic methods. 相似文献
104.
Metallic nanoparticles bridge the length scale between atoms and crystals, exhibiting mesoscopic properties unique to their size. Thus, they have generated much interest for their potential applications as chemical or biological sensors and particularly as waveguides for light in nanoscale structures. [Y. W. C. Cao, R. C. Jin, and C. A. Mirkin, Science 297, 1536 (2002); H. J. Lezec et al., Science 297, 820 (2002); S. A. Maier, P. G. Kik, and H. A. Atwater, Appl. Phys. Lett. 81, 1714 (2002); J. M. Oliva and S. K. Gray, Chem. Phys. Lett. 379, 325 (2003)]. One important direction of research into the properties of individual metal nanoparticles involves the controlled variation of their geometry, which can yield new and tunable optical properties that simple spherical configurations do not possess. [T. S. Ahmadi, Z. L. Wang, T. C. Green, A. Henglein, and M. A. Ei-Sayed, Science 272, 1924 (1996)]. A prime example of this is the core-shell nanostructure that has a central material surrounded by differing cladding layer. 相似文献
105.
106.
Well-aligned ZnO nanorod arrays were prepared on substrates by hydrothermal growth under different conditions. The effect of preparing conditions on the deposition of ZnO nanorods was systematically studied by scanning electron microscopy, X-ray diffraction and photoluminescence spectroscopy. It is demonstrated that the growth conditions such as pre-treatment of the substrates, growth temperature, deposition time and the concentration of the precursors have great influence on the morphology and the alignment ordering of ZnO nanorod arrays. Pre-treatment of substrates, including dispersion of ZnO nanoparticles and subsequent annealing, not only plays a main role in governing the rod diameter, but also greatly improves the rod orientation. Although the rod diameter and its distribution are mainly determined by pre-coated ZnO nanoparticles, they can also be monitored to some extent by changing the concentration of the precursors. The growth temperature has a little influence on the orientation of nanorods but it has great impact on their aspect ratio and the photoluminescent property. Kinetic studies show that the growth of ZnO nanorods contains two distinct step: a fast steps within the first hour, in which the nanorods tend to be short and wide, and a slow step, in which long rods with high aspect ratio are obtained. 相似文献
107.
高度取向ZnO单晶亚微米棒阵列的制备与表征 总被引:2,自引:0,他引:2
通过低温压热的方法,在经过预先处理长满晶核的SnO2导电玻璃基底上制备出具有高度取向的ZnO亚微米棒阵列.用扫描电子显微镜(SEM)、选区电子衍射(SAED)及X射线粉末衍射(XRD),对制备出的ZnO亚微米棒的结构和形貌进行了表征.SEM测试结果表明,ZnO亚微米棒是六方型的,近乎垂直地长在基底上,棒的直径为400~500 nm,长度约为2 μm. SAED和XRD结果表明,ZnO亚微米棒为单晶,属于六方晶系,并且沿[001]方向择优取向生长. 相似文献
108.
毛细管粘度计动能和残液改正的综合效应 总被引:1,自引:0,他引:1
对玻璃毛细管粘度计驱动静压的动能损耗和器壁粘附液体的残液效应作了统一的处理, 说明两者紧密相关, 不能分离。毛细管粘度计的工作方程具有η/ρt=A~*-B~*/t2-C~*/t4的形式, 其中A~*, B~*、C~*为仪器常数, 均与粘度计的尺寸和残液效应因子有关。理论指出, 在习惯用的Poiseuille-Hagenbach公式动能改正项中引进的数值因子m是由于液体粘附于球泡器壁引起的后果, 相当于m=1+C~*/B~(*t2), 从而解释了数值因子随Reynold数增加而增大的事实。列举了溶液相对粘度的计算公式和仪器常数的订定方法, 并给出了文献和实验的例证。 相似文献
109.
110.
Weihua Xue Xiaoyun Cheng Jian Fan Huajia Diao Chunming Wang Lei Dong Yi Luo Jiangning Chen Junfeng Zhang 《Tetrahedron letters》2007,48(35):6092-6095
A mild and one-pot protocol for the efficient and stereoselective synthesis of 1,2-trans-aldosyl mercaptans is presented. 相似文献