谈谈建筑玻璃幕墙的防雷方法     

胡定 《气象研究与应用》2006,27(3):55-57

对建筑玻璃幕墙的雷电危害及防雷措施进行分析,阐述玻璃幕墙防雷的有关做法。  相似文献   

金属套管井中电磁测井响应的数值计算   总被引：2，自引：1，他引：1       下载免费PDF全文

沈金松  孙文博 《地球物理学进展》2007,22(6):1781-1790

分析了金属套管井中有限尺寸线圈的电磁响应特征,讨论了井眼泥浆参数、套管参数和不同线圈尺寸对电磁测井响应的影响,考察了金属套管中电磁测井对地层电阻率变化的灵敏度.径向非均匀介质的模拟计算表明,在套管井中井眼泥浆对电磁测井的影响较大,必须进行校正.在低频条件下,井间测量响应中金属套管与地层的电磁响应是非耦合的,两者可以分离.在套管参数一定时,套管响应与地层的响应的比值近似一个常数.电磁响应对地层电阻变化的灵敏度分析显示,井间电磁测量在储层研究尺度对地层电阻率变化响应灵敏,套管引起的衰减稳定.在其它参数相同的前提下,线圈直径的增大有助于有效电磁响应信号的增强,给大井间距测量提供了可能.不同磁导率金属套管的电磁响应分析表明,电磁测井中,采用非磁性或弱磁性套管要优于一般的铁磁性套管.  相似文献   

Transport properties of low-sanidine single-crystals, glasses and melts at high temperature     

Maik Pertermann  Alan G. Whittington  Anne M. Hofmeister  Frank J. Spera  John Zayak 《Contributions to Mineralogy and Petrology》2008,155(6):689-702

Thermal diffusivity (D) was measured using laser-flash analysis from oriented single-crystal low-sanidine (K_0.92Na_0.08Al_0.99Fe³⁺ _0.005Si_2.95O₈), and three glasses near KAlSi₃O₈. Viscosity measurements of the three supercooled liquids, in the range 10^6.8 to 10^12.3 Pa s, confirm near-Arrhenian behavior, varying subtly with composition. For crystal and glass, D decreases with T, approaching a constant near 1,000 K: D _sat ∼ 0.65 ± 0.3 mm² s⁻¹ for bulk crystal and ∼0.53 ± 0.03 mm² s⁻¹ for the glass. A rapid decrease near 1,400 K is consistent with crossing the glass transition. Melt behavior is approximated by D = 0.475 ± 0.01 mm² s⁻¹. Thermal conductivity (k _lat) of glass, calculated using previous heat capacity (C _P) and new density data, increases with T because C _P strongly increases with T. For melt, k _lat reaches a plateau near 1.45 W m⁻¹ K⁻¹, and is always below k _lat of the crystal. Melting of potassium feldspars impedes heat transport, providing positive thermal feedback that may promote further melting in continental crust.  相似文献   

玻璃幕墙防护侧击雷的施工方法   总被引：1，自引：1，他引：0  

邵志明 《内蒙古气象》2009,(2):47-48

主要讲述了玻璃幕墙侧击雷防护施工方法、防雷措施及玻璃幕墙防雷接地的几种形式,是在玻璃幕墙防雷施工过程中的一些认识,供参考。  相似文献   

TEM中心回线中—远带响应特征   总被引：1，自引：0，他引：1  

蒋邦远 《物探与化探》2010,34(2)

近20年来,中心回线观测已进入全域时段,然而有关中—远带响应特征的文章极为少见,致使用户困惑,比如晚延时响应值大于早延时响应值(ε-上凸)、在同一测点2种仪器系统观测结果相差太大等。对此笔者做了详细分析。结果表明,中—远带响应特征基本为4种,ε-上凸只是其中之一,导致所测响应出现差别的主要原因是接收线圈延时。因此,若工作于中—远带,必须确切测定线圈延时,合理选择发射回线边长。  相似文献   

浅海底瞬变电磁探测技术研究新进展     

王艳  刘长胜  林君  周逢道  李慧  周国华 《吉林大学学报(地球科学版)》2005,(Z1)

瞬变电磁法应用于浅海底进行资源勘探或工程地质勘查时,需要将仪器系统和观测装置置于海底,以克服海水屏蔽效应。因此,要求能够远程控制仪器进行自动化数据采集;同时,受工作环境影响,需要将观测装置小型化;另外,通过拖曳式测量提高工作效率。总结课题组目前的研究成果,就仪器系统研制、观测装置小型化、拖曳式测量及海水影响等内容的研究进展进行了简要叙述。  相似文献   

Assessment of the geological and hydrogeological environment at a site of government-level conflict in Incheon, Korea     

J. E. Lee  K. K. Lee 《Environmental Geology》1998,35(4):278-286

 The natural environment of an environmental conflict site in Incheon, Korea was assessed with a focus on the hydrogeological environment. Residents had made claims against a company because of health problems, including skin tumors. More specifically, the residents suspected that their drinking groundwater had been contaminated by glass fibers which had caused the health problems. Air, soil, and groundwater samples were analyzed to estimate whether environmental pollution could have caused the problems claimed by the residents. No specific evidence was found from this study to support the groundwater contamination by glass fibers, but groundwater contamination by leaked fuel oils was confirmed in the course of evaluating the glass fiber problem. Received: 16 May 1997 · Accepted: 18 August 1997  相似文献   

玻璃钢夹砂管在顶管工程中的应用     

律文田 《岩土钻凿工程》2008,(1):99-101

近年来,玻璃钢夹砂管在（管工程中的到越来越广泛的应用,以广州市某污水工程顶管施工为例,介绍了玻璃钢夹砂管在流砂地层的应用,以及在顶管施工中所要注意的事项和应对措施,以供工程技术人员和同类工程参考。  相似文献   

Coaxial coil towed EMI sensor array for UXO detection and characterization     

Haoping Huang  Bill SanFilipo  Alex Oren  I.J. Won 《Journal of Applied Geophysics》2007,61(3-4):217-226

A new broadband electromagnetic induction (EMI) array sensor, GEM-5, for detecting and characterizing Unexploded Ordnance (UXO) has been developed in order to provide high production rates for EMI surveys. The sensor consists of a single rectangular loop transmitter around a linear array of seven pairs of coaxial receiver coils, with each coil in a pair located at the same vertical distance above and below the loop transmitter. The coil pairs are wired in an inverted series so that the signal consists of the difference between the voltage induced in the upper and lower coils. This particular configuration provides a high degree of primary field cancellation, dense spatial sampling rate due to simultaneous and continuous operation of all sensors, suppression of motion-induced and environmental noise, and strong source fields at typical UXO burial depths providing deep detection range. Our prototype tests indicate that the array yields a lower static and motion-induced noise over the critical low frequencies than that of existing sensors, and in particular, the signal-to-noise ratio at 90 Hz is 32 dB higher. Environmental noise can be largely removed from the difference measurements. The field test results from UXO test sites show that the prototype sensor has smoother background and appears to detect more seeded targets than the GEM-3 concentric sensor, however some of that gain can be attributed to higher power transmitter electronics.  相似文献   

Development of an online analyzer of atmospheric H₂O₂ and several organic hydroperoxides for field campaigns     

S. Franois  I. Sowka  A. Monod  B. Temime-Roussel  J.M. Laugier  H. Wortham 《Atmospheric Research》2005,74(1-4):525-545

An online automated instrument was developed for atmospheric measurements of hydroperoxides with separation and quantification of H₂O₂ and several organic hydroperoxides. Samples were trapped in aqueous solutions in a scrubbing glass coil. Analyses were performed on an HPLC column followed by para-hydroxyphenylacetic acid (POPHA) acetic acid and peroxidase derivatization and fluorescence detection. Analytical and sampling tests were performed on different parameters to obtain optimum signal-to-noise ratios, high resolution and collection efficiencies higher than 95% for H₂O₂ and organic hydroperoxides. The obtained performances show large improvements compared to previous studies. The sampling and analytical devices can be coupled providing an online analyzer. The device was used during two field campaigns in the Marseilles area in June 2001 (offline analyzer) and in July 2002 (online analyzer) at rural sites at low and high altitudes, respectively, during the ESCOMPTE and BOND campaigns. During the ESCOMPTE campaign, H₂O₂ was detected occasionally, and no organic hydroperoxides was observed. During the BOND campaign, substantial amounts of H₂O₂ and 1−HEHP+MHP were often detected, and two other organic hydroperoxides were occasionally detected. These observations are discussed.  相似文献