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排序方式: 共有182条查询结果,搜索用时 15 毫秒
61.
Liu Zhong Sun Xiangfu Zhou Xiaohong Lei Xiangguo Jin Hanjuan Guo Yingxiang Pan Qiangyan Zhang Yuhu Chen Xinfeng Luo Yixiao Wen Shuxian Yuan Guanjun Li Guangsheng Yang Chunxiang 《中国物理C(英文版)》1995,19(2):106-109
Excited states of 117Xe were populated via the reaction 92Mo(28Si,2pn)at 115MeV.The emitted promt γ-rays were measured by using in beam γ-ray experimental techniques.Five bands in 117Xe have been identified,two of them are observed for the first time,and the three known bands are extended to higher spins. 相似文献
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本文对传输网路管理(监控)中的传输监控网与电信管理网(TMN)的关系;准同步数字系统(PDH)与同步数字系统(SDH)的监迭管理以及传输监控网与电话管理网的关系进行了分析探讨。 相似文献
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白光干涉测量技术具有精度高和非接触式测量的优点,是超精密加工领域中的一项重要测量手段。针对白光干涉测量技术容易受环境振动影响的问题,提出了一种动态垂直扫描干涉测量方法(DVSI)。该方法将白光干涉光路分为两个成像通道,得到与白光干涉图同步移相的准单色光干涉图。通过相位-倾斜迭代方法(PTI)对准单色光干涉图进行处理得到实际的移相扫描位置,对白光干涉信号进行相干峰位置的定位,并计算出粗糙的形貌分布,之后利用局部最小二乘方法(LLS)计算出精细的相位分布,将粗糙形貌以及精细相位相结合来复原出待测件的三维形貌。本研究通过数值仿真和实验对比对该方法进行了验证,结果表明本方法具有较好的抗振性能。 相似文献
66.
Particle size distribution and characteristics of polycyclic aromatic hydrocarbons during a heavy haze episode in Nanjing,China 总被引:4,自引:0,他引:4
A heavy haze episode caused by agricultural burning occurred in Nanjing from November 7 to November8,2009.PM10 samples were collected on normal and hazy days from November 1 to November 14,2009 at both city and suburban sites of Nanjing.Sixteen PAHs were measured during the day and at night.The results show that the concentrations of the particles were as high as 579.55 and 573.43 μg/m3 during the haze episode at the city and suburban sites,respectively,3-4 times higher than those on a normal day.The proportions of fine particles during the haze episode were also higher than those on a normal day.The changes in the concentrations of PAHs were in accordance with the concentrations of the particles.Highmolecular-weight PAHs composed approximately 80% of the total PAHs on normal days and during the haze episode.The concentration of PAHs in fine fractions significantly increased during the haze episode,and this increase was most obvious at night at the city site.The proportion of total carcinogenic PAHs in fine particles was relatively high during the haze episode at both sampling sites,particularly at night at the city site. 相似文献
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Minliang Liu Yuhu Zhang Xiaohong Zhou Yingxiang Guo Zhong Liu Xiangguo Lei Jianjun He Yong Zheng Wanju Luo Lihua Zhu Shuxian Wen 《中国科学G辑(英文版)》2003,46(3):330-336
High-spin states in141Nd have been studied using in-beam γ-ray spectroscopic techniques via the130Te(16O, 5nγ)141Nd reaction. The level scheme of141Nd has been extended up to an excitation energy of 7614.5 keV including 12 new γ rays deexciting 15 new levels. According
to particle-vibrator coupling and semi-empirical shell model calculations, the level structure of141Nd can be well interpreted by coupling an h11/2 neutron-hole to the respective excited states in142Nd core. 相似文献
69.
解大系统稳定性的积分方程法 总被引:4,自引:0,他引:4
本文通过分解积分方程组,并建立积分方程法比较原理,化大系统为低维系统,进而讨论了带时滞的时变大系统的稳定性,给出了新的结果,这一方法也可以用来讨论其它类型大系统的稳定性问题. 相似文献
70.
Shuxian Wu Juan Li Hong Liang Liping Wang Xian Chen Guixiao Jin Xiaoping Xu Huang-Hao Yang 《中国科学:化学(英文版)》2017,60(5):628-634
Supramolecular vesicles have received great attention in biomedical application due to their inherent features, including simple synthesis and tunable amphiphilicity of the building blocks. Despite tremendous research efforts, developing supramolecular vesicles with targeted recognition and controlled release remains a major challenge. Herein, we constructed a novel aptamer-based self-assembled supramolecular vesicle by host-guest complexation of pyrene, viologen lipid, and cucurbit[8]urils for pH-responsive and targeted drug delivery. The proposed supramolecular vesicles are easy to be assembled and offer simple drug loading. Based on confocal fluorescence microscopy and cytotoxicity experiments, the drug-loaded supramolecular vesicles were shown to possess highly efficient internalization and apparent cytotoxic effect on target cancer cells, but not control cells. Furthermore, through simple aptamer or drug substitution, supramolecular vesicles can be applied to a variety of target cell lines and drugs, making it widely applicable. Taking advantage of the easy preparation, good stability, rapid pH response, and cell targeting ability, the aptamer-based self-assembled supramolecular vesicles hold great promise in controlled-release biomedical applications and targeted cancer therapy. 相似文献