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811.
著名女作家严歌苓2008年推出新作《小姨多鹤》,秉承其一贯厚重而轻盈、深沉而灵动的创作风格,又一次轰动了文坛。小说成功地塑造了朱小环、竹内多鹤两个典型的女性形象,将读者的心智又拉入了那个硝烟弥漫的乱世,倾听着大时代下小女人生命的歌哭。作家与她笔下的人物一同吟唱着人性之美和普世之爱。 相似文献
812.
813.
Yunsheng Ma Junfa Zhu Shuxian Zhuang Zhiquan Jiang Weiping Zhou Runsheng Zhai Xinhe Bao 《科学通报(英文版)》2002,47(14):1184-1186
The preparation of SmOx/Rh(100) and CO adsorption on this model surface have been investigated with Auger electron spectroscopy (AES), X-ray photoelectron
spectroscopy (XPS) and temperature programmed desorption spectroscopy (TDS). The oxygen adsorption on the SmRh alloy surface
leads to the aggregation of Sm on the surface. The thermal treatment of this oxidized surface induces the further agglomeration
of SmOx on the Rh(100) surface. Compared with CO TDS on the clean Rh(100) surface, three additional CO desorption peaks can be observed
at 176, 331 and 600 K on the SmOx/Rh(100) surface. The CO desorption peak at 176 K may originate from CO adsorbed on SmOx islands, while the appearance of the CO adsorption peaks at 331 and 600 K, depending on the oxidation state of Sm, is attributed
to CO species located at the interface of SmOx/Rh(100). 相似文献
814.
815.
提出了同时测定稀土——铝合金中La,Ce的分光光度法。采用混合掩蔽剂SSA+EDTA-Zn+EDTA联合掩蔽大量基体及工La,Ce以外的稀土元素。改变掩蔽剂用量调节体系化学平衡,以ASApA显色成功地进行了La,Ce同时测定。此法用于重稀土铝合金样品分析,得到了满意的结果。 相似文献
816.
817.
辅助应急管理系统的设计与实现 总被引:6,自引:0,他引:6
结合辅助应急管理系统(EDMS)研制实例,从系统结构、推理系统、数据库系统、图形系统、集成网络系统等重要方面对实现快速、有效的CEMS作了较深入的探讨,为今后各种具体CEMS的研制提供了科学依据。 相似文献
818.
Maize transformation via pollen tube pathway and the inheritance of transgene in progeny 总被引:2,自引:0,他引:2
The herbicide-resistant gene als was introduced into maize inbred line Qi319 through pollen-tube pathway. The inheritance of transgene was studied up to 33 generation. Transformation was performed by applying plasmid DNA carrying solution on the severed styles after self-pollination, or just prior to selfpoll/nation. After herbicide screening, PCR and Southern blot analysis, seventeen plants were confirmed positive in TO generation, and sixteen of them were self-bred to construct family to 33 progeny. Through PCR analysis and herbicide screening in offspring, four lines were confirmed following a 3 : 1 Mendelian segregation ratio. In other lines the numbers of positive plants were lower than expected. Therefore, it is necessary to select large population in progeny to produce stable inherited lines when transgene was delivered by pollen tube method. 相似文献
819.
Hong-mei Shao Xiao-yi Shen Xue-tian Li Yong Cui Wei Zhang Wen-di Xu Zhong-cai Shao Yu-chun Zhai 《矿物冶金与材料学报》2021,28(4):729-737
Flower-like ZnO microstructures were successfully produced using a hydrothermal method employing ZnSO4/(NH4)2SO4 as a raw material. The effect of the operating parameters of the hydrothermal temperature, OH?/Zn2+ molar ratio, time, and amount of dispersant on the phase structure and micromorphology of the ZnO particles were investigated. The synthesis conditions of the flower-like ZnO microstructures were: hydrothermal temperature of 160°C, OH?/Zn2+ molar ratio of 5:1, reaction time of 4 h, and 4 mL of dispersant. The flower-like ZnO microstructures were comprised of hexagon-shaped ZnO rods arranged in a radiatively. Degradation experiments of Rhodamine B with the flower-like ZnO microstructures demonstrated a degradation efficiency of 97.6% after 4 h of exposure to sunshine, indicating excellent photocatalytic capacity. The growth mechanism of the flower-like ZnO microstructures was presented. 相似文献
820.
Synthesis and characterization of semiconductor zinc sulfide nanotubes by soft-template method 总被引:1,自引:0,他引:1
LǖRuitao CAOChuanbao ZHAIHuazhang ZHUHesun 《科学通报(英文版)》2004,49(10):1005-1008
ZnS nanotubes have been successfully synthe-sized from solutions containing a surfactant, Triton X-100(t-octyl-(OCH2CH2)χOH, χ=9, 10). X-ray diffraction (XRD),transmission electron microscope (TEM) and selected areaelectron diffraction (SAED) are employed to characterize thestructure and morphology of as-synthesized product. XRDand SAED pattern indicate that as-obtained products consist of pure polycrystalline cubic-phase ZnS structures. TEM images reveal that most of the products are tubular struc-tures, with diameters ranging between 37--52 nm andlengths up to 3 μm. The wall thickness of as-obtained ZnSnanotube is around 9 nm. The growth mechanism of ZnSnanotubes has also be proposed. 相似文献