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511.
p-HPcZn-SiO_2纳米粒的制备与表征 总被引:1,自引:0,他引:1
运用微乳液法制备出β-四(羧基苯氧基)锌酞菁-二氧化硅纳米粒,初步的研究结果表明其在水溶液中纳米粒粒径比较均一,且具有良好的分散性和稳定性.与未包裹酞菁的在水溶液中相比,该纳米粒的单线态氧量子产率得到了明显提高. 相似文献
512.
An Yan GuoHui Ding ZhenFeng Zhou Hui Dong YaKun Zhang Lei Zhu YunGang He GuoQing Zhang YiXue Li Bing Sun Zhong Huang Ke Lan Li Jin HongYan Wang XiaoNing Wang Zhong Yang Yang Zhong JianXin Dai YaJun Guo Hao Wang XiaoYan Che Fan Wu ZhenGan Yuan Xi Zhang ZhiWei Cao XiaoNong Zhou JiaHai Zhou ZhiYong Ma GuangZhi Tong GuoPing Zhao WeiRong Jin Hui Xiong 《科学通报(英文版)》2009,54(13):2164-2167
The outbreak of a novel influenza A (H1N1) virus across the globe poses a threat to human health. It is of paramount importance to develop a rapid, reliable and inexpensive diagnostic procedure. Based on the bioinformatic information from public database, primers specific for influenza A virus surface protein haemagglutinin (HA) of several subtypes (including H1, H2, H3, H5, H7 and H9) were designed. Primer-specific PCR products were subiected to sequencing for accurately distinguishing H1 and H3 subtypes from others. This sequencing-based detection method will not only be applied to rapid detection and simultaneous subtype identification of new influenza A virus H1N1, but also provide the strategies to monitor other new types of influenza virus with explosive potential. 相似文献
513.
超声提取绿茶茶多酚研究 总被引:5,自引:0,他引:5
在单因素基础上,通过正交实验,研究超声提取法对绿茶茶多酚提取率的影响,并优选出提取工艺的最佳条件.结果表明,超声波作用15 min提取率为10.710%,而水提浸作用1 h的提取率仅为10.638%,表明超声提取缩短了时间.正交实验的结果给出超声提取的最佳提取工艺为料液比1:45,时间为15 min,功率为480 W. 相似文献
514.
The main span of Sutong Bridge is a double-pylon, double-plane cable-stayed bridge with steel box girder, which has the world' s longest central span of 1 088 m within cable-stayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, wind-resistance, seismic-resistance, structural nonlinear response and structural static stability were presented individually in this paper. 相似文献
515.
本论文通过人口老龄化对科学、文化、教育发展提出的机遇和挑战;人口老龄化对教育的影响;人口老龄化促进老年文化的发展;三个方面的论述,阐述了当今世界在老年人数快速增加及现代化的时代,正确认识和处理人口老龄化与科学、文化、教育发展的关系是十分重要的。 相似文献
516.
The microstructure and crack behaviour of twinning induced plasticity (TWIP) steel during tensile deformation was investigated with in-situ scanning electron microscopy (SEM). The results show that there are two modes of plastic deformation during tensile test in the Fe-Mn-C TWIP steel: dislocation gliding and deformation twins. During the process of tensile deformation, secondary deformed twins are found. Inclusions have played a role in the course of ductile fracture, and microcracks initiate from inclusions and twin-twin intersections. 相似文献
517.
A multi-burner-port annular flameless ceramic burner (MAFCB) of the shaftless stove for blast furnaces was designed. The characteristics of pressure drop, homogeneousness of the flows at burner ports, and distribution of the flows in the chambers and joint were studied by cold model experiments. This type of ceramic burner was successfully applied in 6# blast furnace at Liuzhou Iron & Steel Co. Ltd. (LISC) and this practice proved that it could be used in the hot blast stove and other stoves with a higher efficiency and a higher steadiness of hot blast temperature at 1200℃. With the combustion of blast furnace gas alone, the thermal efficiency was up to 78.95%, saving energy remarkably. 相似文献
518.
当今社会信息技术的进步对社会的发展产生极其巨大的影响,人在社会发展中的主体地位得到了确定。人在一生中不断学习,发展自己的潜能,不断选择未来被认为是人的基本权利。终生学习的重要性更加凸现,终生学习的观念已被普遍认同。由于信息技术突破时空限制,为教育大众化的同时更加个别化和个性化提供了日益先进的技术支撑。发展远程教育,成为构建终生学习体系中的一项重要内容。在上述背景下,文章讨论了终生学习的特征、实现终生学习的条件,远程教育在终生学习中的作用等问题。 相似文献
519.
Guanqing Jia Bo Li Dengfeng Zhang Tifu Zhang Zhiyong Li Jingrui Dai Shoucai Wang 《自然科学进展(英文版)》2009,19(9):1089-1096
520.
Production of human lysozyme-transgenic cloned porcine embryos by somatic nuclear transfer 总被引:1,自引:0,他引:1
Qiuyan Li Hengxi Wei Ying Guo Yan Li Rui Zhao Yufang Ma Zhengquan Yu Bo Tang Lei Zhang Yunping Dai Ning Li 《自然科学进展(英文版)》2009,19(6):699-704
Due to their physiology and organ size, pigs have significant potential as human disease models and as organ transplantation donors. Genetic modification of pigs could provide benefits for both agriculture and human medicine. In this study, five fetal pig fibroblast cell lines from two species (Wuzhishan and Landrace pigs) were transfected using double-marked human lysozyme (HLY) plasmids (pBC1-HLY-GFP-NEO) by a liposome-mediated method. The ratio of green fluorescent protein (GFP)-expressing cells was >95% in sw7, sw8, slw3 and slw6 cell lines, but only 49.3% in slw9 cells. Cells from the four highly transgenic lines were used as nuclear donors to construct embryos, which were then cultured after fusion and activation by electric stimulation. The rate of cleavage was 76.7%, 48 h after activation. After 7 days, 18.5% of cleaved eggs had developed to the blastocyst stage and 93.3% of blastocysts were GFP-positive. These results indicate that transgenic fetal pig fibroblast cell lines could be obtained by a liposome-mediated method, though the transfection efficiency varied between cell lines. Reconstructed embryos derived from transgenic cells could successfully develop into blastocysts, most of which were GFP-positive. 相似文献