江西省黎川县上水桥金、萤石矿区控矿断裂形成的时效性及脉岩对成矿的屏蔽作用

上水桥金、萤石矿区断裂活动和热液活动均具有多期次特点。成为控矿构造的断裂 ,其活动时间与成矿热液活动时间有较高的统一性 ,在有效时间内活动的断裂控制了金、萤石矿化及矿体。在成矿前脉岩贯入岩体围岩断裂、裂隙 ,防止了热液逸散 ,对成矿起到良好的屏蔽作用。     

基于闪电定位系统的雷击建筑物绕击率分析与区划

通过对重庆地区1999-2008年闪电定位系统监测地闪资料进行数理统计,重点对采用IEEE和DL/T620提供的公式获取的雷击建筑物绕击率进行对比分析,并对重庆全市进行雷击建筑物绕击率区划.结果表明:雷击建筑物绕击率随着滚球半径增大而增加;对于相同滚球半径,IEEE方法获取的雷击建筑物绕击率略高于实际,而低于GB/T21714提供的绕击率;在滚球半径小于120 m时,IEEE方法得到绕击率明显低于DL/T620方法,反之则高于DL/T620方法;采用IEEE公式获取的雷击建筑物绕击率与实际较为吻合,在此基础上获得了能客观反映重庆地区雷击建筑物绕击率表达式,并对不同防雷类别建筑物雷击绕击率进行了区划,为雷电灾害风险评估和防雷设计提供了可靠理论依据.     

通信基站建设诱发雷电灾害事故分析

针对大足县城南中学附近建设移动通信基站后频遭雷击的状况,结合2006—2009年重庆地区ADTD闪电定位系统监测资料,重点分析该校频遭雷击事故原因。结果表明:移动通信基站建设(增加了遭受直击雷和雷击电磁脉冲影响概率)是城南中学频遭雷击的诱因;该校未安装防雷装置,且部分教学楼处于铁塔保护范围外,而位于雷击铁塔的散击区内,是频遭雷击的直接原因。     

探讨计算机房防雷屏蔽的检测方法

简述了电磁场强度的计算方法以及信息系统电子设备对电磁场强度的要求,着重对防雷屏蔽的检测方法进行了探讨,供广大防雷检测人员借鉴。     

Macroscale and mesoscale analysis of concrete as a multiphase material for biological shields against nuclear radiation

The overall thermo‐hygro‐mechanical behavior of concrete is to be investigated, because its bearing capacity is required together with its shielding properties, specifically when concrete structures are exposed to high‐energy neutron fluxes, which represent the next generation facilities designed for the production of high energy radioactive ion beams in physics research. Irradiation in the form of either fast and thermal neutrons, primary gamma rays or gamma rays produced as a result of neutron capture, are learnt to affect concrete as well as neutron fluences of the order of 10¹⁹ n/cm² and gamma radiation doses of 10¹⁰ rad seem to become critical for concrete strength. The collection of data on concrete samples, variously exposed to neutron radiation, has allowed for defining a law for radiation damage within the FEM research code NEWCON3D, assessing the 3D coupled thermo‐hygro‐mechanical behavior of concrete, modeled as a multiphase porous medium, both at the macroscale and the mesoscale level. The required damage law is thought to be a function of the neutron flux impinging the concrete shielding wall, and a good estimate of this quantity has been provided by means of a Monte Carlo code developed by CERN and the National Institute of Nuclear Physics of Milan, Italy; this code handles radiation transport calculations and represents at this day one of the most reliable procedures for dealing with the interaction of radiation and matter. The suggested procedure for the radiation damage evaluation has allowed for discussing on differences between mesolevel and macrolevel approaches. Stochastic contour maps of the expected radiation field, properly interfaced with the numerical FE code, have allowed for obtaining a more precise evaluation of the radiation damage front as well as its evolution in time. Copyright © 2013 John Wiley & Sons, Ltd.     

通信高塔对临近建筑物防雷安全的影响

本文为客观地评述高塔对临近区域的建筑物在防雷方面的现实影响,以某移动基站的通讯塔对其临近的养鸽场造成的雷电影响分析为例,从引雷效应、落雷几率两方面的分析论述了高塔的存在对雷击环境的改变;从空间电磁辐射、静电感应、电磁感应和瞬间电位的抬高四个方面分析了高塔对二次雷击干扰的影响;并就如何消解通信高塔对临近建筑物带来的雷电威胁,提出了在雷电防护手段上应加强的几个关键方面,得出通信高塔影响临近建筑物的防雷安全,但可以采取措施消解这种安全影响的结论。     

提高屏蔽环承压能力实验研究

屏蔽暂堵技术在较短时间内形成的高强度屏蔽环既能有效保护地层又能有效防漏堵漏,屏蔽环强度的高低直接决定地层的承压能力。本文利用屏蔽暂堵原理,在实验室内利用普通钻井液进行改良,通过人工造缝的岩芯进行室内实验,通过对比分析两组实验的不同结果,得出具有实际意义的结论,指导现场的实际工作。     

On new limits of the coefficient of gravitation shielding

New limits of the shielding coefficients in the supposed phenomenon of gravitation shielding have recently become available. The new values are briefly reviewed and discussed in order to update the state of art since some new limits for gravitation shielding are not necessarily the lowest ones which, instead, are those of interest when planning new experimental research or studying theoretically the possible effects of gravitation shielding.     

旅游屏蔽理论定量研究——基于景区系统种群竞争模型

在国内旅游地形象屏蔽理论的研究基础上,提出景区系统种群概念并辨析了其引用的科学性。以游客接待量为衡量标准,利用生态种群竞争模型,建立了景区系统种群的数学模型。在合理假设条件下解析竞争趋向并进行了实证研究,认为景区在不同发展阶段的相对吸引力以及自身学习调节能力是3种不同类型屏蔽产生的主要原因且决定了其发展趋向,据此提出相应的发展策略。     

福山油田保护油气层钻井完井液技术研究

福山油田为典型凝析油气藏,储层孔隙度10%～20%,平均渗透率35?10-3 μm2,属于中孔低渗储层,部分为低孔特低渗储层,且水敏、易塌。通过试验选用了以XZD-Ⅱ为暂堵剂的屏蔽暂堵钻井完井液实施油气层保护,取得了较好的保护效果。