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2003-2017 全部
为您找到包含“国家自然科学基金”的内容共13763

Jia Yanyan ,Qin Jiachang ,Zhou Changfa

Because of its large species diversity, less characters for classification, smaller body and confused taxonomic systems as well as history, the Baetidae is a very complicated taxon in mayfly taxonomy and phylogeny reconstruction. In recent years, some species from Zijin Hill of Nanjing city (Jiangsu Province, Eastern China) are differentiated and identified upon adult-nymph association by rearing in lab. From prostheca of right mandible (as two spines) and hindwings (having 3 longitudinal veins), the species Baetis yixiani Gui and Lu, 1999 is transferred into the genus Alainites Waltz and McCafferty (1994) hereby. More reports and descriptions on Baetidae from Chinese mainland are preparing and will be published later. Hopefully, series papers on this issue can clarify some problems in mayfly taxonomy of China, or even facilitate and boost more researches as well.

2010-03-18

国家自然科学基金;国家自然科学基金(30300037;30570200

The Key Laboratory of Jiangsu Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China,The Key Laboratory of Jiangsu Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China,The Key Laboratory of Jiangsu Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China

#Biology#

0评论(0 分享(0)

Zhao Zihua ,He Dahan ,Zhao Yingshu ,Hang Jia ,Shi Xiangfeng

Minimum Area of Suitable Habitat (MASH) and Minimun Viable Population (MVP) were two important aspects in Population Viability Analysis (PVA). MASH for a viable population can be estimated in several ways. The density-area method estimated MASH as the smallest area in which population can survival for a long time and variation was below 0.05. We used a variant of density-area method to study MASH for aphids, parasitoids, and hyperparasitoids in Northwest of China, where wheat was a main crop in agriculture. The variant was based on the premise that individuals within populations were likely to occur at usually high densities variation when confined to small areas and it estimated MASH as the smallest area beyond which density plateaus. For all 72 sites, aphids, parasitoids and hyperparasitoids occurred in all sites because wheat fields were highly homogeneous. We found that a consistant inverse density-area relationship was present over smaller areas, but different species had different function, especially in different trophic level. MASH of M. avenae, S. graminum, A. avenae, A. gifuensis, A. sp.1 and P. aphidis estimated from density-area relationship were 260, 240, 510, 490, 950, and 990m2 respectially. Results of inverse proportion function according to which MASH of M. avenae, S. graminum, A. avenae, A. gifuensis, A. sp.1 and P. aphidis were 310, 286, 543, 492, 952, and 1003 m2 respectially were similar to that of density-area relationship. We concluded that a negative density-area relationship may be an inevitable consequence of agricultural intensification and farmland fragmentation. We also concluded that different species may have different MASH requirement in agricultural landscape according to body size, migration, trophic level, and habitat quality, which could interpret the phenomenon that highest percent parasitism was always in 800-1000 m2 wheat fields which exceeded MASH of parasitoids and suppressed activity of hyperparasitoids . Finally, we concluded that the value of any MASH as a pest control tool was compromised in Conservation Biological Control (CBC).

2010-03-29

国家自然科学基金(30760045

国家自然科学基金(30860164

Institute of Grassland Sciences, Ningxia University,Institute of Grassland Sciences, Ningxia University,Institute of Grassland Sciences, Ningxia University,Institute of Grassland Sciences, Ningxia University,Institute of Grassland Sciences, Ningxia University

#Biology#

0评论(0 分享(0)

刘先刚,龚卫国

2010-04-22

针对码书模型因算法复杂度高而难以应用到运动目标实时检测中的问题,提出了一种改进的码书建模方法。首先优化了码书模型的参数和训练策略,然后提出一种信息块快速获取策略,利用该策略对获得的目标信息块和时间轴运动信息块进行融合决策,实现了在检测过程中实时分离背景和训练码书模型。实验结果表明:经优化的码书建模方法处理效率大幅度提高的同时,检测性能与原始码书模型一致,能对多变环境快速适应,有效解决了码书建模的实时运动目标检测问题。

国家自然科学基金(CSTC2007AC2018

国家自然科学基金(CSTC2008BB2199

重庆大学光电技术及系统教育部重点实验室,重庆大学光电技术及系统教育部重点实验室

#计算机科学技术#

0评论(1 分享(0)

孙继成,张旭昇,胡雅杰,朱锋 ,魏国孝

2009-10-28

在系统分析研究区地质及水文地质条件的基础上,确定了研究区范围和边界条件,借助GIS技术和FEFLOW建立了研究区地下水系统概念模型和数学模型及相应的地下水系统数值模型。用2004~2005年地下水动态观测井的地下水动态观测资料对数值模型进行了识别和率定,运用识别后的模型对现状水平年(2004年)的地下水系统进行了模拟与分析。结果表明,建立的模型能够较好的反应研究区水文地质空间分布及组合方式,具有一定的代表性,可以用于数值模拟计算。选择2005年为预测初始时间,2015年为终止时间,利用模型对研究区进行预测,在模型运行的10年后,研究区北部区域地下水位上升3~5m,中部区域上升5~10m,南部区域上升10~15m。根据模拟区域地下水上升范围分析,为今后实施排水措施奠定了一定的技术基础,也为排水措施的选址提供了一定的依据。

国家自然科学基金(40421101

国家自然科学基金(10425

兰州大学资源环境学院,兰州大学资源环境学院,兰州大学资源环境学院,四川省清源工程咨询有限公司,兰州大学资源环境学院

#地球科学#

0评论(0 分享(0)

李晓璐,杨光,郑青亮,张耀洲

2009-11-24

钙整合素结合蛋白一般含有4个EF-hand结构域,可与包括血小板αⅡbβ3 integrin 等许多效应蛋白结合并能调节他们的功能。我们从本实验室构建的家蚕蛹cDNA文库中获得一条cDNA序列,通过同源序列比对后发现其为家蚕钙整合素结合蛋白 (Bombyx mori calcium and integrin binding protein,BmCIB)基因, 全长为939 bp,ORF为558 bp,编码165个氨基酸。我们构建了重组表达载体pET28a- BmCIB,在E. coli BL21(DE3)中诱导表达了含有His标签的融合蛋白BmCIB。通过包涵体纯化与亲和层析法进一步纯化融合蛋白并免疫雄性新西兰兔,制备并获得了多克隆抗体。通过实时定量PCR和Western blot分析,我们发现BmCIB 的mRNA和表达的蛋白在五龄家蚕各组织及发育时期广泛分布。其mRNA转录水平以生殖腺和蛹期中最高,蛋白表达在各发育时期均可检测到,各组织中以生殖腺中最多。通过免疫荧光法分析BmCIB蛋白在家蚕Bm5细胞的亚细胞定位,发现其定位于细胞质中。以上工作为进一步研究BmCIB功能奠定了基础。

国家自然科学基金(2007AA021703;2007AA120402

国家自然科学基金(2005CB121006

浙江理工大学生物化学研究所,浙江理工大学生物化学研究所,浙江理工大学生物化学研究所,浙江理工大学生物化学研究所

#生物学#

0评论(0 分享(0)

Li Jinjin,Zhu Kadi

We demonstrate theoretically that it is possible to stop quantum light in vertically coupled InGaAs/GaAs quantum dots systems simply by applying an external voltage. This stopping is based on the form-stable polaritons consisting of quantum light and indirect exciton associated with electromagnetically induced transparency using tunneling instead of pump laser. The indirect exciton dark-state polaritons in the two coupled quantum dots can then be reaccelerated and converted back into a photon pulse via a tunable voltage. The device system has possible applications in quantum information processing by using modern electro-optical technology.

2009-11-30

国家自然科学基金(10774101

国家自然科学基金(10974133

Department of Physics, Shanghai Jiao Tong University,Department of Physics, Shanghai Jiao Tong University

#Physics#

0评论(0 分享(0)

Li Jinjin ,Zhu Kadi

We theoretically propose a scheme to study coherent population oscillation (CPO) in a system of a quantum dot coupled to nanomechanical resonator. Due to nanomechanical vibrations the CPO in a single quantum dot demonstrates novel features. In analogy with CPO in quantum optics, we refer this effect as mechanically induced coherent population oscillation (MICPO). In this scheme, the vibration of the nanomechanical resonator make a contribution to additional auxiliary energy levels so that the transparency phenomenon could be realized in such system. The optical spectrum shows that the transparency based on MICPO can be controlled simply by the intensity of the optical field, the coupling strength and other relevant parameters. Furthermore, our technique provides a detection in a real experiment to measure the decay rate of nanomechanical resonator.

2009-12-01

国家自然科学基金(10774101

国家自然科学基金(10974133

Department of Physics, Shanghai Jiao Tong University.,Department of Physics, Shanghai Jiao Tong University.

#Physics#

0评论(0 分享(0)

汪洋,程素华

2010-01-12

最初定义的埃达克岩是钠质火成岩,其全岩化学成分相当于英云闪长岩、奥长花岗岩和(富斜长石的)花岗闪长岩(TTG);而富钾的“C型埃达克岩”全岩化学成分相当于(狭义)花岗岩、石英二长岩和(富碱性长石的)花岗闪长岩。目前的实验岩石学结果不支持玄武质源岩部分熔融形成SiO2含量中等(56 ~ 67 %)的“C型埃达克岩”的假设。但中等富钾程度的贫硅(或高Mg#值)玄武质源岩在相对高压低比例部分熔融条件下可以形成酸性(SiO2 > 70%)“C型埃达克岩”。

国家自然科学基金(0

国家自然科学基金(0

1) 中国地质大学地质过程与矿产资源国家重点实验室,北京100083;2) 中国地质大学(北京)岩石矿物教研室,北京100083,1) 中国地质大学地质过程与矿产资源国家重点实验室,北京100083;2) 中国地质大学(北京)岩石矿物教研室,北京100083

#地球科学#

0评论(0 分享(0)

王玉,王贵学,罗向东,邱菊辉

2010-01-12

为了观察基底刚度对表皮细胞增殖、迁移的影响,将表皮细胞接种在三种不同刚度的硅胶基底上。通过细胞生长曲线、MTT法和细胞周期检测表皮细胞的增殖情况;用细胞划痕法进行表皮细胞迁移率的测定。结果发现表皮细胞的增殖速度在高刚度基底上更快,同时在高刚度基底上迁移率远远高于其在低刚度基底上的迁移率。推测可能是基底力学性质的变化引起整合素介导的力学信号发生改变,从而调控表皮细胞的增殖与迁移。

国家自然科学基金(30730093

国家自然科学基金(30970721

生物流变科学与技术教育部重点实验室,重庆大学生物工程学院,生物流变科学与技术教育部重点实验室,重庆大学生物工程学院,第三军医大学创伤、烧伤与复合伤国家重点实验室,生物流变科学与技术教育部重点实验室,重庆大学生物工程学院

#生物学#

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张超,李玥,钟芳

2012-01-13

本文以玉米淀粉为实验材料,分别以不同体积配比的α-淀粉酶和糖化酶,在不同酶用量、pH、反应温度、时间、底物浓度条件下制备玉米多孔淀粉,通过单因素和正交实验优化最佳工艺,并研究了多孔淀粉成孔情况。最佳制备工艺如下:酶用量1.0%,α-淀粉酶与糖化酶体积比1:3,pH 5.4,反应时间20h,反应温度45℃,底物浓度30%,多孔淀粉得率为51.15%,吸油率为79.27%,为原淀粉吸油率的2.9倍。颗粒成孔效果最好,微孔较多且分布均匀,大部分深入颗粒内部,颗粒整体保持完好,并且淀粉粒度减小不大,更加均一化。

国家自然科学基金(30871744

国家自然科学基金(30901000

江南大学食品学院,江苏 无锡 214122,江南大学食品学院,江苏 无锡 214122,江南大学食品学院,江苏 无锡 214122

#食品科学技术#

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