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由胰岛素调控pi3激酶引发的果蝇滞育的自然变异

应用昆虫学报 , 2007,
Abstract:
预测的气候变化改变了捕食者在生态系统过程的间接作用

应用昆虫学报 , 2007,
Abstract:
橡胶坝建设对邻近河岸生态系统影响与修复方法探讨
Study of the Impact and Repair Methods of Adjacent Riparian Ecosystem after the Rubber Dam Completion
 [PDF]

段震, ,, 李杰友
Advances in Environmental Protection (AEP) , 2014, DOI: 10.12677/AEP.2014.43012
Abstract:

以泰安市大汶河拦蓄枢纽2号橡胶坝为例,针对橡胶坝建成后上下游河岸水土生态环境变化,采用工程辅助 + 生物两栖植物模式营造河岸、河坡和库湾植被生长的土壤环境;选择适生两栖植物进行造林复绿;打造新的水环境景观系统进行水土生态修复。实践表明,上述方法对营造和维护河岸水土生态系统、保护水资源和水环境具有良好的效果。
The paper took Tai’an Dawen River No.2 rubber dam as an example. According to the changes of soil and water ecological environment after the completion of the rubber dam, soil environment of the river bank, the river slope and the bay for vegetation growth was built by using the engineering aided and biological amphibious plant pattern. The suitable amphibious plant was selected for recovery of green and a new system of water environment landscape was created for water and soil ecological restoration. The practice showed that the above methods have good effects on creating and maintaining riparian water and soil ecosystem.

煤矿“一通三防”存在的问题及解决方法
赵南方,
煤炭工程 , 2009,
Abstract: 通过分析神新公司“一通三防”的现状,从安全投入、通风系统、瓦斯防治、防灭火系统、防尘系统等几方面总结成功经验,指出存在的一些问题,同时提出解决对策。
windows2003中基于web的信息安全通道的构建
, 妍?
河北科技大学学报 , 2006, DOI: 10.7535/hbkd.2006yx01021
Abstract: 介绍了如何在windows2003server上用iis服务器建立基于ssl的信息安全通道的全部过程,其中包括对dns,activedirectory以及ca服务的配置,web服务器端证书和客户端证书的申请、安装以及配置,证书链的获取与安装等内容,简述了基于ssl的信息安全通道的原理及应用,阐明了为什么要使用信息安全通道来传输信息,并且提出了iis服务器上高于128位加密的实验性方案。
荧光偏振关联光谱用于单分子动力学特性的研究
Single Molecule Dynamics Measurement by Using Fluorescence Correlation Spectroscopy
 [PDF]

王铁, , 肖连团, 贾锁堂
Modern Physics (MP) , 2012, DOI: 10.12677/MP.2012.23005
Abstract: 本文以SR单分子作为荧光探针,利用两个正交偏振探测通道的荧光偏振关联函数分别测量聚合体薄膜表面与薄膜内部的动力学特性。分析发现薄膜表面的单分子正交偏振的荧光具有反关联特性,荧光偏振互关联函数反映了聚合体薄膜表面的转动动力学特性,测量了单分子转动再取向的特征时间。相应镶嵌在薄膜内部的荧光分子受到环境的束缚,转动自由度低。

In this paper, the dynamics of polymer surface and its interior are measured by using fluorescence correlation spectroscopy with the SR dye molecules as optical probs. It is found that there are the anti-correlated characteristics to the orthogonal polarization of single molecules fluorescence when the SR molecules are absorbed onto the PMMA surface. It is presented directly that the rotational dynamics of the polymer surface is revealed by the cross-correlation function, and the rotational time is measurement. Accordingly, the molecules embedded inside the polymer film are restricted by the surrounded environment and have low rotational freedom degree.

泥岩盖层压力封闭期及其研究意义
石波,,付广
天然气地球科学 , 1998,
Abstract: 在深入研究泥岩盖层压力封闭形成的地质条件及地质历史基础上,提出了泥岩盖层压务封闭期的概念及确定方法。通过压力封闭期与烃源岩排气高峰期之间匹配关系的研究,阐述了对泥岩盖层压力封闭期研究的意义。以松辽盆地三肇凹陷青山口组泥岩盖层对侏罗系气源岩和自身生成天然气压力封闭有效性为例作了说明。
Analysis of Spatial Accessibility for School Redistricting in Rural China:a Case Study of the Secondary Schools in Gongyi City,Henan Province
农村中小学布局调整之空间可达性分析——以河南省巩义市初级中学为例

,李小建,雪峰
遥感学报 , 2008,
Abstract: As a result of birth rate decreases in China, the total number of pupils has steadily reduced since 1990s. Inevitably, restricting the prmi ary and secondary school is an mi portant issue for local governments. Meanwhile, along with a number of school closures in recent years in rural China, new problems are frequently reported, such as a long distance of traveling to school for some communities, the quota excess of teaching classes in many schools and uneven distribution of teaching resources among schools. For school redistricting planning, both the educational equality and school efficiency is mi portant. The objective of this paper is to assess the educational equality by introducing geographic information systems (GIS) and the conceptof spatial accessibility in school redistricting. Based on the literature review of the planning principles and methods for school redistricting considering the educational need and supply and the service equality and efficiency, the authors attemptto introduce a framework ofschool planning in ruralChina. The key technicalprocedures are enlarginggeographic database such as schools, geodemographics and transportation networks, and calculating the spatialaccessibility ofschoolservices forevery communityusingGIS. The spatial accessibility indices are used to assess the spatial equality of educational service and tomeasure the rationality of school redistricting. The spatial relationshipsbetween population distribution and secondary schools inGongyiCity, Henan Province are evaluated using five accessibility measures, .i e. the ratio mode,l nearest distance mode,l chance accumulationmode,l gravitymodel and mi proved gravitymode.l The case study shows that there are uneven spatial patterns in terms of the per capita educational resources, the distance to nearest schoo,l the chance of school choice and the balance between school supplies and community needs. The locationa advantages or disadvantages identified in the thematicmaps have potentials in future school planning. The authors argue to introduceGIS technology and spatial accessibilitymodels in school redistricting in ruralChina. It is also suggested to explore and verify the spatial patterns of school choice and estmi ate detailed school supplies and community needswith usingHuffmode,l which lays a theoretical foundation for school facility planning.
致密砂岩储层启动压力与微观孔隙结构关系实验研究
Experimental Study on the Relationship between Start-Up Pressure Gradient and Microscopic Pore Structure in Tight Sandstone Reservoirs
 [PDF]

李自远, 肖长剑, 樊华, 鲍俊驰,
Mine Engineering (ME) , 2015, DOI: 10.12677/ME.2015.33021
Abstract:
致密砂岩储层是指储层致密(一般渗透率< 0.1 × 10?3 μm2)、只能经过压裂等改造才能获得经济产量的砂岩储层,它是形成非常规油气藏的主要类型之一。与常规砂岩储层相比,其中流体的流动遵循低速非达西流动规律,即存在大小不一的启动压力梯度。本文通过实验室测得不同地区致密砂岩储层启动压力梯度,结果表明,致密砂岩储层启动压力梯度随渗透率减小而急剧增大,利用扫描电镜和压汞方法进行微观分析发现,致密砂岩孔喉急剧减小,以纳米级孔喉比例为主,说明致密砂岩储层渗流特征受复杂的微观孔隙结构所控制。
The tight sandstone reservoir refers to the reservoir density (generally permeability under 0.1 × 10?3 μm2), which can only get sandstone reservoir of economic output after fracturing modification. It is one of the main types of unconventional reservoir formed. Compared with the conventional sandstone reservoir, the flow of the fluid follows the law of non-Darcy flow at low speed. Based on the existence of different starting pressure gradients, a large number of experiments show that tight sandstone reservoir starting pressure gradient increases sharply with the decrease of the permeability. The microscopic analysis accordingly shows that tight sandstone pore throat reduces sharply. Giving priority to nanometer scale pore throat ratio, it shows that tight sandstone reservoir percolation characteristics are controlled by the complex microscopic pore structure.
基于LabVIEW和激光测振仪的三维振动测量系统
A Three-Dimensional Vibration Measuring System Based on LabVIEW and Laser Doppler Vibrometer
 [PDF]

陈康, 叶岗, 陈士钊,, 深逢
Instrumentation and Equipments (IaE) , 2015, DOI: 10.12677/IaE.2015.33008
Abstract: 基于LabVIEW软件开发工具和激光多普勒测振仪,开发了一套能够测量物体三维振动信息的系统。该系统主要由五台单维激光测振仪组成的硬件系统、数据采集卡以及软件系统组成。软件系统利用硬件系统和数据采集系统提取的五路振动数据,通过算法最终转化成物体空间三维振动信息(X、Y和Z三个方向的时域信息),对时域信息进行分析,最终可以得到物体振动的频谱信息、自功率谱、互功率谱等。该系统采用非接触的方式,可以准确测量出物体在空间中的三维振动信息,通过这些信息,可以准确判断物体的振动状态。
The equipment can measure the vibrator’s three-dimensional vibration information, which has been developed based on the LabVIEW software development tools and Laser Doppler Vibrometer (LDV). It mainly includes hardware system that contains five LDVs, data acquisition system and software system. In the experiment, the hardware system and data acquisition system get the five channel vibration data which are used for converting to the three-dimensional vibration informa-tion (the time-domain data of X axis, Y axis and Z axis) by software system. With these data, we can also get the power spectrum, cross-power spectrum and so on. The equipment can accurately measure the vibration data in a non-contact way, which can be used to analyze the state of the vi-brator.
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