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861.
一种新型的计算机温度检测系统 总被引:3,自引:1,他引:3
论述了一种新型的两级总线型电子冷藏箱生产线系统 ,介绍了该系统的技术性能和特点 ,指出了其应用推广的价值 相似文献
862.
Wu Lin Li Hong Chen Shao-feng Qin Yi-min Zong Zhi-ming Wei Xian-yong Zou Guo-lin 《武汉大学学报:自然科学英文版》2002,7(2):227-230
The reaction of acenaphthene with nitrobenzene was investigated in the presence of AlCl3. The results showed that the reaction proceeded via carboncation-electrophilic substitution reaction and free radical substitution
reaction pathway. The products of acenaphthenyl phenylamine and biacenaphthyl could be synthesized by this reaction. The influence
of the amount of AlCl3 and the temperature on the components of products were also studied in this reaction.
Foundation item: Supported by the National Nature Science Foundation of China (No. 29676045)
Biography: Wu Lin (1965-), male, Postdictor, research direction: PAHs catalytic conversion and its biologic toxicity. 相似文献
863.
Construction of multivalent DNA vaccines forMycobacterium tuberculosis and its immunogenicity 总被引:1,自引:0,他引:1
The coding regions of Ag85B MPT-64, and ESAT-6 secreted proteins were cloned initially into the eukaryotic expression vector pJW4303, then transformed to E. coli Top 10 strain for plasmid DNA extraction and further analysis. Plasmids containing the right insertion were sequenced to confirm their identity. COS7 cells were transfected with a mixture containing serially diluted plasmid DNA encoding three secreted proteins and Lipofectin (Gibco). The supernatants and pellets prepared from various cell lines were run on SDS-PAGE gel and the expression of these proteins in COS7 cells were demonstrated by immunoblot using polyclonal or monoclonal antiserum of M.TBH37Rv. 21 days after first vaccination of C57BL-6 mice by all three recombinant eukaryotic expressing vectors, antibody titer for Ag85B reached 1∶3200. 21 days after second vaccination, the antibody titer reached 1∶102400. The highest antibody levels induced by multivalent vaccines after the second injection were equal to or even greater than the highest antibody levels of single DNA vaccine reported in literature after third injections. Antibody titer of MPT-64 was 1∶50 after the first injection and it reached 1∶200 after the second injection. No antigen-specific antibody against ESAT-6 was detected in sera harvested from immunized mice 21 days after both injections. Antigen-specific IFN-g level of Ag85B was 110 pg/mL while no antigen-specific IFN- g level of ESAT-6 and MPT-64 was detected even after third injections. To our knowledge, it is the first time that studies of polyvalent recombinant DNA vaccines against TB were carried out in C57BL-6 mice. Our results indicated that multiple DNA vaccines could be used to enhance protective responses against M.TB. 相似文献
864.
SAR interferometry (InSAR) has a high potential for surface displacement mapping in the range from millimeter to meter. In this paper the potential of ERS-1/2 SAR interferometry for mapping subtle land subsidence has been investigated. A time series of ERS-1/2 SAR data from February 1993 to February 2000 is collected from measurements taken in Suzhou city, Jiangsu Province, China, eight ERS-1/2 SAR images are used to create seven interferograms, and three differential interferograms are produced using the three-pass method, which clearly show the spatial extent of land subsidence. The deformation maps are validated by leveling surveys, the correlation coefficient and standard deviation between them are 0.943 and 0.1706 respectively. Based on seven benchmarks, the subsidence rates are estimated, the overall trends are in close agreement with InSAR results. The results of study show that for the mapping of land subsidence in urban environments InSAR has a strong potential due to its cost-saving, high resolution and accuracy. 相似文献
865.
超氧化物歧化酶 (SOD)作为一种生物活性酶 ,在治疗由氧化应激所导致的疾病方面有着非常广阔的应用前景 .本文综述了国内外近年来有关 SOD的存在和结构、SOD活性的测定及模拟等方面的研究进展 . 相似文献
866.
Abnormal overpressure distribution and natural gas accumulation in foreland basins,Western China 总被引:1,自引:0,他引:1
Shizitan in Jixian County, Shanxi Province, is a site of transitional period from Paleolithic to Neolithic. The dating and the sporopollen analysis show that the middle reaches of the Yellow River where the site is located had been maintaining a steppe environment during 35.1-9.4 kaBP, in which, 35.1-17 kaBP belonged to the last glacial. With cold and dry climate, this period featured a desert steppe environment. In the late of this period, the area had a cold and half-humid steppe environment. The 17.0-11.9 kaBP belonged to the early- and mid-period of the last deglaciation. Mild and half-arid steppe alternates with mild and half-arid steppe, with a small amount of deciduous broadleaf species. During the period of 11.9-10.5 kaBP, cold and dry glacial climate appeared once more, featuring a desert steppe environment. During 10.5-9.4 kaBP, it is mild and half-arid, and later transited toward warm and half-humid. The early phase of this period featured a steppe environment and the later transited into a steppe environment with fairly more deciduous broadleaf species. Microlith, a mark of a transitional period from Paleolithic to Neolithic, was distributed mainly in 17.0-11.9 kaBP. The relatively warm, half-arid and fluctuating steppe environment in the early and medium period of the last deglaciation made a contribution to the appearance and development of Microlithic culture. 相似文献
867.
鸡足山珊瑚菌资源调查 总被引:3,自引:0,他引:3
本报道了作自1997年至1999年间采集于宾川鸡足山的珊瑚菌12种,其中9种是可食的,3种是有毒的,并简要介绍了各种珊瑚菌的形态特征。 相似文献
868.
计算电磁学研究进展 总被引:18,自引:0,他引:18
洪伟 《东南大学学报(自然科学版)》2002,32(3):335-339
介绍了东南大学计算电磁学研究中心近年来在计算电磁学方面的研究进展,包括吸收边界条件、区域分裂法、不变性测试方程法、Green函数、电磁成像、直线法、泛函方法、毫米波无源电路的数值分析等方面的具有代表性的一些研究成果。 相似文献
869.
针对屏蔽同轴圆柱分层介质结构,给出格林函数的一般解析解,这种解以级数的形式来表示,具有形式简单可应用到任意多层介质的特点,公式的推导是通过先给出分层结构中含待定系数无穷级数的格林函数通式,然后利用边界条件与源条件,得到层与层之间的递归关系进而求解这些系数,这样的解为分析屏蔽同轴圆柱分层介质结构提供了一种新的有效工具。 相似文献
870.
基于重复控制的CVCF电源波形控制技术 总被引:4,自引:0,他引:4
对重复控制的理论,特别是模型不精确情况下的控制器设计问题进行了研究,给出了适用于恒压恒频逆变电源的重复控制器,提高了产出版社为电源在非线性负载情况下的输出电压品质。文中分析了重复管制器对谐波的抑制机理;从系统极点分布规律入手,推导出控制器与受控对象之间的最佳关系;基于对消的思想,给出了采用部分对消的重复控制器设计方法,并在控制器中引入了特殊的FIR函数,提高了系统的稳定性。最后,通过实验对新的设计法进行了验证。实验表明,采用新的控制器,逆变电源输出波形的谐波含量降到了0.446%,误差收敛速度也大大提高。 相似文献