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1.
红外光电隔离避雷器,是利用光电方法,隔离数据传输系统是的电气联系。本文对光电转换及避雷器原理作了较详尽地探讨,也对接地系统降阻剂配制和施工方法进行阐述。  相似文献   

2.
三江平原沼泽地主养鲤鱼塘能量转换效率研究   总被引:1,自引:0,他引:1  
杨富亿 《湖泊科学》1995,7(3):263-270
对1988~1992年三江平原沼泽地泥炭池主养鲤鱼生态系统的能量转换效率进行了研究分析。结果表明,一个生长期浮游植物毛初级生产力对太阳辐射能的转换效率为0.204~0.308%;鲢鳙净产量对浮游植物净产量的转换效率为1.195~4.815%;太阳能转换为鱼类总净产量的生态学效率为0.067~0.123%。总辅助能、总生物能和饲料辅助能转换为鱼类总净产量的效率分别为8.91~14.05%、10.96~17.20%和11.06~17.57%.在2500kg/hm~2、3500kg/hm~2及5000kg/hm~2三个净产量级型池塘中,以5000kg/hm~2产量级的能量转换效率为最佳型。  相似文献   

3.
经济、高效、稳定的通信技术是强震观测和地震工程研究的重要基石,将光纤通信技术应用于数字强震动台网,是对强震仪现有通信方式的改进和完善,它既可以独立成网,也可以接入国际互联网.本文详细研究各种类型强震仪的通信接口,将远程光纤通信分为基于RS-232串口和基于RJ-45以太网口两个方案,其方法是通过不同型号的光电转换设备和光纤将强震仪和计算机连接起来,它具有保证数据可靠性、完整性和避免强震仪通信引雷等诸多优点.  相似文献   

4.
目前,我国地震观测手段有不少观测仪器是利用光点感光照相记录,如磁变仪、倾斜仪、以及其他地震仪器等。其工作程序繁杂、人为误差大,不利于观测系统数字化。随着数字处理现代化和自动传输系统在地震部门的应用和发展,光点感光照像记录的方法,已无法再适应科技发展变革的步伐。从五十年代起就有人提出过这个问题,并进行研究,但因受科技条件的制约,未能取得突破性进展。随着光电技术的发展,为解决光电转换奠定了基础。国家地震局分析预报中心师会等同志,经过一年时间的研制,采用目前国际最新技术(CCD  相似文献   

5.
从能量的角度研究对隔震换能控制系统对建筑结构的减震控制作用,它既能通过转换地震能量来减轻结构的振动,又可以利用转换来的能量作进一步的振动控制.通过研究换能装置的控制力与隔震层刚度比的关系,提出了换能装置控制力的建议公式,并研究了不同换能装置与隔震层设计组合对换能效率和控制效果的影响,给出了隔震换能系统的设计流程,可使隔震换能系统换能效率达到70%左右,振动控制效果达到65%以上.  相似文献   

6.
在定量中子照相散射校正时需要考虑中子转换屏对不同角度入射中子的响应,中子转换屏的角度响应研究在中子照相散射校正中具有很重要的意义。本文在理论上推导中子转换屏的角度响应的解析式,并利用蒙特卡罗程序MCNP5对该解析式进行验证。利用蒙特卡罗方法对中子转换屏角度响应的影响因素进行研究。给出中子转换屏的角度响应与转换屏厚度以及入射中子能量之间的关系,中子转换屏的角度响应随着转换屏的厚度增大而增大,随着入射中子能量的增大而减小,并得到6LiF-ZnS(Ag)转换屏的最佳厚度为0.3mm。   相似文献   

7.
通过1根钢筋混凝土柱和8根不同构造措施下SRC-RC转换柱的低周反复荷载试验,研究SRC-RC转换柱在压、弯、剪共同作用下的抗震性能.分析了试件的主要破坏形态、滞回曲线、骨架曲线和延性,探讨了不同构造措施对SRC-RC转换柱抗震性能的影响,为合理确定SRC-RC转换柱的构造措施提供参考.  相似文献   

8.
地磁观测资料的连续性非常重要,为解决滚筒停转报警问题,本文详细介绍了使用光电转换的地磁光记录滚筒停转报警器的工作原理和制作方法,提供了电原理图,以供参考或制作。  相似文献   

9.
利用安徽省地磁台站2007-2009年数字化观测资料,应用地磁转换函数方法,对华东地区ML4.0以上地震进行对应关系研究,发现不同台站、不同周期的转换函数参量与安徽及邻近地区地震存在一定的对应关系,为今后数据研究提供参考.  相似文献   

10.
218Po快速测氡仪的研制   总被引:2,自引:1,他引:1  
^218Po快速测氡仪是通过收集、测量氡子体中的一个短寿命子体^218Po核素衰变时辐射出α射线的强度来显示氡气场的分布规律.仪器采用高效接收、光电转换、多极倍增、放大方法实现了对α射线的采集.通过后期处理、计算,间接测量和了解氡的存在与分布情况。  相似文献   

11.
探测器是辐射成像系统中的关键器件之一,探测器的性能优劣和成像系统的最终指标关系密切,因此在做成像系统设计时关于探测器的物理计算足非常关键的内容.本文利用MCNP模拟了3种闪烁体材料的性能指标(粒子探测效率,能量沉积率,有效沉积因子)是设计高能辐射成像系统的基础工作之一,具有借鉴意义.  相似文献   

12.
The resonance transition 2P-2S of the atomic hydrogen (Lyman-alpha emission) is the strongest and most conspicuous feature in the solar EUV spectrum. The Lyman-alpha radiation transfer depends on the resonance scattering from the hydrogen atoms in the atmosphere and on the O2 absorption. Since the Lyman-alpha extinction in the atmosphere is a measure for the column density of the oxygen molecules, the atmospheric O2 density and temperature profiles can be calculated thereof. A detector of solar Lyman-alpha radiation was manufactured in the Stara Zagora Department of the Solar-Terrestrial Influences Laboratory (STIL). Its basic part is an ionization camera, filled in with NO. A 60 V power supply is applied to the chamber. The produced photoelectric current from the sensor is fed to a two-channel amplifier, providing analog signal. The characteristics of the Lyman-alpha detector were studied. It passed successfully all tests and the results showed that the so-designed instrument could be used in rocket experiments to measure the Lymanalpha flux. From the measurements of the detector, the Lyman-alpha vertical profile can be obtained. Programs are created to compute the O2 density, atmospheric power and temperature profiles based on Lymanalpha data. The detector design appertained to ASLAF project (Attenuation of the Solar Lyman-Alpha Flux), a scientific cooperation between STIL—Bul.Acad.Sci., Stara Zagora Department and the Atmospheric Physics Group at the Department of Meteorology (MISU), Stockholm University, Sweden. The joint project was part of the rocket experiment HotPay I, in the ALOMAR eARI Project, EU’s 6th Framework Programme, Andøya Rocket Range, Andenes, Norway. The project is partly financed by the Bulgarian Ministry of Science and Education.  相似文献   

13.
针对目前地震水氡模拟观测操作繁琐、干扰因素多等现状,引入新型水氡观测仪进行检测并与FD-125测氡仪开展对比试验研究。两款水氡观测仪在地震监测氡观测仪检测平台标准氡室校准,并依托九江地震台相同水样和环境下开展对比测量表明,在静置时间为1 h前提下,新型水氡观测仪重复性、相对误差、相对固有误差、固有本底符合技术要求,与FD-125测氡仪对比测量数据的一致性较好,但灵敏度指标有待提升。该仪器整体设计基本满足地震模拟水氡测量发展需求,可减少人工操作带来的测量误差,提升测量效率和数据质量。  相似文献   

14.
The geophysical mechanism behind astronomical time–latitude residuals (ATLR) are discussed. The photoelectric astrolabe at Yunnan Observatory (YO) observed apparent synchronous anomalous ATLR before the Wenchuan M8.0 earthquake (EQ) in May 12, 2008 and the Lushan M7.0 EQ n April 20, 2013. We compared the ATLR from the YO photoelectric astrolabe and EQ data since 1976. Anomalous ATLR was observed before several strong EQs in the Yunnan Province. We believe the photoelectric astrolabe can be used to predict strong EQs and the anomalous ATLR are a potential EQ precursor.  相似文献   

15.
本文利用Geant4模拟了FD3013数字γ辐射仪探测器探测晶体,对137Cs(0.661MeV)的γ射线的探测效率,和TH-PPLCT教学仪防护铅罐对137Cs源的防护效果,并建立了简易人体模型,仿真计算了人体吸收剂量,结果显示防护铅罐屏蔽后的辐射剂量在可接受的水平内。  相似文献   

16.
Volcanic aerosol emissions have been studied for the first time by in situ photoelectric charging. Explorative studies on Mt Etna reveal large concentrations of particles below 1000 nm with the spectrum peaking in the size range of 100–1000 nm diameter. Although a large fraction of the particles is already charged upon emission, the net electrical charge carried by the aerosol turned out to be close to zero.Particles with high photoelectric yield vary greatly in their relative abundance and seem to occur mainly at active points of the volcano.  相似文献   

17.
This paper describes a method to calibrate a neutron capture sonde equipped with a high resolution γ-ray detector, and analyze log data. The method utilizes the 1460.8-keV passive γ-ray of 40K, the 770.3-keV capture γ-ray of 39K, and a capture γ-ray from a target element. An equation containing the spectral line intensities for the two capture γ-rays, nuclear capture data, and the detector efficiency function expresses the concentration of the target element as a multiple of the 39K concentration. The concentration of 39K is easily deduced from the 40K concentration, which is calculated directly from the line intensity for the 1460.8-keV γ-ray in a passive γ-ray spectrum.The calibration automatically adjusts to changes in the neutron transport properties of the logged medium that may result, for example, from variations in the H density and the concentrations of neutron poisons. Fluctuations in the neutron source output are similarly accommodated. The calibration utilizes U.S. Department of Energy (DOE) passive γ-ray calibration standards that contain well established concentrations of K, U, and Th. The passive γ-rays from K, U, and Th (and the U and Th decay progenies) provide data for the detector efficiency function determination.Data for proof-of-principle demonstrations of the method were acquired by logging boreholes penetrating the shallow subsurface at a DOE waste site with a simple, reliable neutron capture logging system. The system had a 252Cf source and a high purity germanium (HPGe) detector. Time gating could not be used to sort signals originating from capture and activation, but the excellent energy resolution permitted capture γ-ray identifications based solely on the γ-ray energies. Cl, H, and other elements were detected and assessed.A conventional calibration and data analysis method was also employed. The method was specific to Cl and was based on measurements in two Cl-impregnated concrete blocks. Cl concentrations inferred with this method were often consistent with the concentrations determined with the new method. When the two methods produced different Cl concentrations, the discrepancies could be explained by variations in formation parameters.  相似文献   

18.
破坏性地震发生后,埋压人员的快速搜索是地震救援工作成功的重要因素。微波成像生命探测仪作为当前废墟搜索的装备之一,近年来得到了广泛应用。但救援队利用现有综合训练场地进行该类装备的测试方法,在装备针对性测试和深度功能认知方面存在着一定局限性,影响了微波成像生命探测仪的现场使用效率和技术发展。为此,本文在充分调研国内外主流地震模拟废墟训练场地的基础上,提出了相关的改进意见,结合汶川地震废墟三维采集数据和队伍实战经验,给出微波搜索装备综合测试方法,并在国家地震紧急救援训练基地完成了测试平台的搭建,取得较好的装备测试效果,为应急救援装备电子化和标准化测试提供参考。  相似文献   

19.
三探测器密度测井的Monte Carlo模拟   总被引:12,自引:1,他引:11       下载免费PDF全文
为了改善传统岩性密度测井仪的缺陷,本文基于传统的双 源距探测器密度测井仪,提出在负源距范围内增加一个反散射探测器,构成新的三探测器密 度测井仪器. 利用Monte Carlo方法通用程序MCNP(3B),从光子与地层相互作用的机理出发 ,计算得到了反散射探测器、长源距探测器和短源距探测器的光子通量的能谱分布、光子通 量与源距的关系、光子通量与地层密度的关系、源距与探测深度的关系以及计数能窗等. 从 结果看,三探测器密度测井仪的长、短源距探测器对地层的响应关系与双源距密度测井仪的 长、短源距探测器一致,而反散射探测器对地层具有明确的响应关系,其响应关系与长、短 源距探测器近似相反,且其计数率很高. 因此,在负源距范围内增加第三个探测器是可行的 ,这将有利于提高密度测井的测量精度和垂向分辨率. 同时表明了Monte Carlo方法在核测 井仪器早期研制中的有效性,对仪器设计具有指导作用.  相似文献   

20.
Particulate emissions from Mt. Etna in the fine-size range below 100 nm were studied in June and September 1989. The aerosol particles were characterized by size, concentration and photoelectric activity. These quantities are sensitive to the physical and chemical properties of the magma. Concentrations varied from 104 to 107 cm-3. The size distributions peak below 20 nm (radius) and are very narrow. The particles are generated mainly by nucleation and condensation of magmatic volatiles in a strong temperature gradient. The photoelectric activity of these particles can indicate high magma levels and increased exsolution of volatiles. It is therefore related to the observed activity of the respective crater and may be helpful as a prediction tool when used in conjunction with other volcano-monitoring techniques.  相似文献   

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