排序方式： 共有36条查询结果，搜索用时 31 毫秒
1.
随着IT技术的不断发展,出现了越来越多的新设备,操作系统为了保持对这些新设备以及已有老设备的支持,其内核就要加入越来越多的驱动代码,驱动代码的加入使得原本已经复杂的内核更加庞大,且这些代码可能潜伏着许多漏洞,威胁系统安全。而微内核系统将设备驱动独立于用户空间,不再处于内核中,使得设备驱动不会影响到内核的安全,这种设计对于减少系统安全威胁帮助很大。 相似文献
2.
Xin Pan Jian-cheng Qi Ming Long Hao Liang Xiao Chen Han Li Guang-bo Li Hao Zheng 《Journal of Zhejiang University. Science. B》2010,11(10):771-778
The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model
for the study of human infectious diseases. In this study, we describe the development of a large-scale automatic multi-functional
isolation chamber for use with medium-sized laboratory animals carrying infectious diseases. The isolation chamber, including
the transfer chain, disinfection chain, negative air pressure isolation system, animal welfare system, and the automated system,
is designed to meet all biological safety standards. To create an internal chamber environment that is completely isolated
from the exterior, variable frequency drive blowers are used in the air-intake and air-exhaust system, precisely controlling
the filtered air flow and providing an air-barrier protection. A double door transfer port is used to transfer material between
the interior of the isolation chamber and the outside. A peracetic acid sterilizer and its associated pipeline allow for complete
disinfection of the isolation chamber. All of the isolation chamber parameters can be automatically controlled by a programmable
computerized menu, allowing for work with different animals in different-sized cages depending on the research project. The
large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized
laboratory animals in high-level bio-safety laboratories. 相似文献
3.
美国前参议员富布赖特,1959—1974年任参议院外交委员会主席。在此期间,他通过发表演说和举行一系列听证会,为美国对华政策的转变作了大量舆论准备工作,对美国实现从“遏制并孤立”到“遏制但不孤立”对华政策的转变起了重大推动作用。 相似文献
4.
李美幸 《韩山师范学院学报》2001,22(1):52-56
英国“光辉孤立”政策的结束是国际关系史研究领域的一个重要课题。本文全面分析了英国政府放弃“光辉孤立”政策的历史背景,指出英国综合国力的下降;德国推行“世界政策”对英国的威胁;法俄同盟在对英国殖民霸权的 挑战以及美国在西半球对英国的排挤是英国“光辉孤立”政策结束的原因。 相似文献
5.
何晨青 《温州大学学报(社会科学版)》2010,23(1)
英国在19世纪下半叶的外交政策被描述为"光辉孤立",这是英国在强国林立的欧洲保持自身政策灵活性和追求利益最大化的关键.就政治因素来看,"光辉孤立"是均势外交的一种表现,但深究其文化渊源,"光辉孤立"是英国政治传统中的保守主义和功利主义、外交丈化中的制衡观念以及不列颠民族特性和岛国文化的综合结果. 相似文献
6.
Yan Xing Hong-yun Peng Xia Li Meng-xi Zhang Ling-ling Gao Xiao-e Yang 《Journal of Zhejiang University. Science. B》2012,13(10):839-845
The active metabolite in the post-harvested biomass of zinc(Zn) and cadmium(Cd) hyperaccumulator Sedum alfredii Hance from phytoextraction is of great interest in China.The current study demonstrates that a salidroside-type metabolite can be yielded from the Zn/Cd hyperaccumulator S.alfredii biomass by means of sonication/ethanol extraction and macroporous resin column(AB-8 type) isolation.The concentrations of Zn and Cd in the salidroside-type metabolite were below the limitation of the national standards. 相似文献
7.
本文分析了企业网络面临的安全威胁及网络安全隔离技术对网络安全威胁的防范作用,并在分析研究了几种常用的网络安全隔离技术之后,结合企业网络的具体应用需求,提出了3种企业网络应用环境下的网络安全隔离方案。 相似文献
8.
用厌氧培养的方法从酸泡菜中分离出一菌株。经细菌形态学和生理生化特性鉴定为肠膜明串珠菌。再经进一步生理生化特性鉴定为肠膜明串珠菌葡聚糖亚种 相似文献
9.
Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl
chloride. A novel long-chain acyl-derivative of epigallocatechin-3-o-gallate (EGCG) was first isolated from purification of LTP by high-speed countercurrent chromatography (HSCCC) using a solvent
system composed of n-hexane-ethyl acetate-methanol-water (1∶1∶1∶1, v/v). The molecular structure of the acyl-derivative, Epigallocatechin-3-O-gallate-4′-O-hexadecanate, was elucidated by means of elemental analysis, IR,1H-NMR and MS spectra.
Project (No. 200010) supported by Zhejiang Provincial Natural Science Foundation, China 相似文献
10.