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四川冶勒红豆杉迁地保护调查与设计研究
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作者 严贤春 周材权 胥晓 《西南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第4期522-525,529,共5页
四川冶勒自然保护区有国家一级保护植物红豆杉,因建立水电站,水库淹没区的红豆杉需进行迁地保护。为此,对水库淹没区的红豆杉资源进行了调查研究,并对红豆杉迁移地和原生地的生活及生态环境进行了比较研究,由此做出了红豆杉迁地保护分... 四川冶勒自然保护区有国家一级保护植物红豆杉,因建立水电站,水库淹没区的红豆杉需进行迁地保护。为此,对水库淹没区的红豆杉资源进行了调查研究,并对红豆杉迁移地和原生地的生活及生态环境进行了比较研究,由此做出了红豆杉迁地保护分析论证和风险分析。 展开更多
关键词 红豆杉 地保护 资源调查 地比
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汉代廷尉考述 被引量:5
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作者 沈刚 《史学集刊》 CSSCI 北大核心 2004年第1期15-20,共6页
廷尉是汉代掌管刑狱的最高职官。其主要职掌有决狱 ,包括行政和军政系统中二千石以上的官吏 ,宗室犯罪 ,及谋反等重罪 ;部分法令的制订 ;决天下疑狱等。但在皇权至上的政治格局下 ,廷尉的权力受到其他职官的制衡。作为司法官员 ,廷尉需... 廷尉是汉代掌管刑狱的最高职官。其主要职掌有决狱 ,包括行政和军政系统中二千石以上的官吏 ,宗室犯罪 ,及谋反等重罪 ;部分法令的制订 ;决天下疑狱等。但在皇权至上的政治格局下 ,廷尉的权力受到其他职官的制衡。作为司法官员 ,廷尉需要具备一定的专业法律素质 ,西汉武帝之后 ,这一职官也要有相应的经学修养 ,这同汉代政治文化背景的变迁有着密切关系。另外 ,廷尉还以众多的僚属为支撑 ,使其能正常行使职能。 展开更多
关键词 廷尉 决狱 制令 迁选 僚属
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Rovibrational State-Selectivity in Photoassociation through Multi-photon Transitions
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作者 王荣 邱明辉 修俊玲 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期497-502,I0003,共7页
The rovibrational state-selectivity in photoassociation (PA) is investigated for the ground electronic state of OH radical. The calculated results show that population can be transferred from continuum state to the ... The rovibrational state-selectivity in photoassociation (PA) is investigated for the ground electronic state of OH radical. The calculated results show that population can be transferred from continuum state to the target states through three-, four-, and nine-photon transitions by choosing suitable pulse parameters and initial collision energy. To control population transfer to a lower rovibrational state, a shorter pulse frequency has to be chosen and the photon number transferred to target state should be increased. In PA process, some associated OH radicals can be dissociated via intermediate and background states, which decreases the nal population of the target state. 展开更多
关键词 PHOTOASSOCIATION Multi-photon transition State-selectivity Intermediate state
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Effect of atomic structure on migration characteristic and solute segregation of ordered domain interfaces formed in Ni_(75)Al_xV_(25-x) 被引量:1
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作者 张明义 陈铮 +3 位作者 王永欣 马光 卢艳丽 范晓丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期604-611,共8页
Based on the microscopic phase-field model, ordered domain interfaces formed between D022 (Ni3V) phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migrati... Based on the microscopic phase-field model, ordered domain interfaces formed between D022 (Ni3V) phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migration characteristic and solute segregation of interfaces were studied. It is found that the migration ability is related to the atomic structure of interfaces, and three kinds of interfaces can migrate except the interface (001)//(002) which has the characteristic of L12 (Ni3Al) structure. V atoms jump to the nearest neighbor site and substitute for Ni, and vice versa. Because of the site selectivity behaviors of jumping atoms, the number of jumping atoms during the migration is the least and the jumping distance of atoms is the shortest among all possible modes, and the atomic structures of interfaces are unchanged before and after the migration. The preferences and degree of segregation or depletion of alloy elements are also related to the atomic structure of interface. 展开更多
关键词 atomic migration characteristic solute segregation site selectivity microscopic phase-field ordered domain interface
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Screening, identification and desilication of a silicate bacterium 被引量:5
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作者 周洪波 曾晓希 +2 位作者 刘飞飞 邱冠周 胡岳华 《Journal of Central South University of Technology》 EI 2006年第4期337-341,共5页
The strain Lv(1- z) isolated from the Henan bauxite was characterized by morphological observation, biochemical and physiological identification, and 16S rDNA sequence analysis. The influences of temperature, initia... The strain Lv(1- z) isolated from the Henan bauxite was characterized by morphological observation, biochemical and physiological identification, and 16S rDNA sequence analysis. The influences of temperature, initial pH value, the volume of medium, shaking speed and illite concentration on the desilicating ability of the strain Lv(1- z) were investigated. The results show that the bacterium is a Gram-negative rod-shaped bacterium with oval endspores and thick capsule, but without flagellum. The biochemical and physiological tests indicate that the strain Lv(1- z) is similar to Bacillus rnucilaginosus. In GenBank the 16S rDNA sequence similarity of the strain Lv(1- z) and the B. rnucilaginosus YNUCC0001(AY571332) is more than 99%. Based on the above results, the strain Lv(1- z) is identified as B. rnucilaginosus. The optimum conditions for the strain L(1- z) to remove silicon from illite are as follows., temperature is 30℃ ;initial pH value is 7.5; medium volume in 200 mL bottle is 60 mL; shaking speed of rotary shaker is 220 r/m ; illite concentration is 1%. 展开更多
关键词 SCREENING IDENTIFICATION Bacillus rnucilaginosus silicon removal
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Measurement Induced Enhancement of Squeezing in Nondegenerate Two-Photon Jaynes-Cummings Model 被引量:4
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作者 YE Sai-Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6X期1065-1068,共4页
Squeezing properties in the nondegenerate two-photon Jaynes-Cummings model are investigated. The effects of direct selective atomic measurement and the application of the classical field followed by atomic measurement... Squeezing properties in the nondegenerate two-photon Jaynes-Cummings model are investigated. The effects of direct selective atomic measurement and the application of the classical field followed by atomic measurement are analyzed. Different values of the parameters of the classical field are taken into account. It is found that the field squeezing can be enhanced by measurement. 展开更多
关键词 two-mode squeezing two-photon transitions selective atomic measurement
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Influential Factors in Employment Location Selection Based on “Push-Pull” Migration Theory—A Case Study in Three Gorges Reservoir Area in China 被引量:10
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作者 XU Ding-de ZHANG Ji-fei +3 位作者 XIE Fang-ting LIU Shao-quan CAO Meng-tian LIU En-lai 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1562-1581,共20页
In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull"... In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics—in addition to the economic characteristics of the sample counties—multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment(age, years of education and social networks), family structure(the number of laborers, elders, children and students), home village characteristics(location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies. 展开更多
关键词 Off-farm employment Location selection Migrants Push-Pull migration theory Three Gorges Reservoir region China
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Selection rules of electromagnetic transitions for chirality-parity violation in atomic nuclei 被引量:2
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作者 Yuanyuan Wang Xinhui Wu +2 位作者 Shuangquan Zhang Pengwei Zhao Jie Meng 《Science Bulletin》 SCIE EI CSCD 2020年第23期2001-2006,M0004,共7页
The nuclear Chirality-Parity(ChP) violation, a simultaneous breaking of chiral and reflection symmetries in the intrinsic frame, is investigated with a reflection-asymmetric triaxial particle rotor model. A new symmet... The nuclear Chirality-Parity(ChP) violation, a simultaneous breaking of chiral and reflection symmetries in the intrinsic frame, is investigated with a reflection-asymmetric triaxial particle rotor model. A new symmetry for an ideal ChP violation system is found and the corresponding selection rules of the electromagnetic transitions are derived. The fingerprints for the ChP violation including the nearly degenerate quartet bands and the selection rules of the electromagnetic transitions are provided. These fingerprints are examined for ChP quartet bands by taking a two-j shell h11/2 and d5/2 with typical energy spacing for A = 130 nuclei. 展开更多
关键词 Chiture Chiplex Spontaneously symmetry breaking Selection rules of electromagnetic transitions
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In vivo RNAi screen identifies candidate signaling genes required for collective cell migration in Drosophila ovary 被引量:1
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作者 LUO Jun ZUO JunTao +5 位作者 WU Jing WAN Ping KANG Di XIANG Cong ZHU Hong CHEN Jiong 《Science China(Life Sciences)》 SCIE CAS CSCD 2015年第4期379-389,共11页
Collective migration of loosely or closely associated cell groups is prevalent in animal development, physiological events, and cancer metastasis. However, our understanding of the mechanisms of collective cell migrat... Collective migration of loosely or closely associated cell groups is prevalent in animal development, physiological events, and cancer metastasis. However, our understanding of the mechanisms of collective cell migration is incomplete. Drosophila border cells provide a powerful in vivo genetic model to study collective migration and identify essential genes for this process. Using border cell-specific RNAi-silencing in Drosophila, we knocked down 360 conserved signaling transduction genes in adult flies to identify essential pathways and genes for border cell migration. We uncovered a plethora of signaling genes, a large proportion of which had not been reported for border cells, including Rack1 (Receptor of activated C kinase) and brk (brinker), mad (mother against dpp), and sax (saxophone), which encode three components of TGF-β signaling. The RNAi knock down phenotype was validated by clonal analysis of Rack1 mutants. Our data suggest that inhibition of Src activity by Rackl may be important for border cell migration and cluster cohesion maintenance. Lastly, results from our screen not only would shed light on signaling pathways involved in collective migration during embryogenesis and organogenesis in general, but also could help our understanding for the functions of conserved human genes involved in cancer metastasis. 展开更多
关键词 DROSOPHILA border cell migration signaling pathway TGF-β Brk RACK1 Src42A Src64B
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通信枢纽楼能耗运行分析研究 被引量:1
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作者 樊春锋 伍建萍 《电信工程技术与标准化》 2016年第5期89-92,共4页
如何在业务量不断增加,电源容量无法扩容的情况下,更好地解决供电能力紧张、机房装机位不足、机房散热等问题,是本论文的研究意义所在。本文通过对S省通信枢纽楼能耗运行分析,给出以上难点的合理化建议和建设指导原则。
关键词 枢纽楼 变压器 能耗 红色预警
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