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101.
Anhua He Gang Zhao Na Xue Jun Wang Bailin Guo Miaoxi Guo Zizhong Fu Institute of Crustal Dynamics China Earthquake Administration Beijing China Earthquake Administration of Tianjin Municipality Tianjin China China Earthquake Networks Center Beijing China 《地震学报(英文版)》2009,(1):101-106
Using Altera's Quartus Ⅱ,Nios Ⅱ IDE and Sopc Builder development tools,the proton precession magne-tometer principle host hardware platform is designed in a cyclone Ⅱ series FPGA chip(EP2C35).The proton precession magnetometer principle host core circuit's single-chip system-logic design is achieved by building and configuring the Nios Ⅱ soft-core processor,developing the IO interface and sensor control circuits,programming some hardware units' VHDL code,for example the equal precision cymometer and the DPL... 相似文献
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为了解WCZ-3S陆地地磁日变观测系统的性能,分别在江苏盐城和海南三亚将WCZ-3S与Sentinel基站磁力仪、WCZ-2磁力仪、WCZ-3磁力仪进行了同步测量,通过比较分析的方法,对WCZ-3S的测量精度、测量曲线的准确性、磁暴识别功能进行了检验。测试结果表明:WCZ-3S的实测精度约为0.3 nT,稍逊于Sentinel基站磁力仪;WCZ-3S与其他几台磁力仪所测曲线的幅值、相位保持一致;WCZ-3S的实时成像功能可帮助台站工作人员对海洋磁力测量期间的磁暴现象进行识别。 相似文献
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K. Shinoda M. Yamakata T. Nanba H. Kimura T. Moriwaki Y. Kondo T. Kawamoto N. Niimi N. Miyoshi N. Aikawa 《Physics and Chemistry of Minerals》2002,29(6):396-402
Infrared absorption spectra of brucite Mg (OH)2 were measured under high pressure and high temperature from 0.1 MPa 25 °C to 16 GPa 360 °C using infrared synchrotron radiation
at BL43IR of Spring-8 and a high-temperature diamond-anvil cell. Brucite originally has an absorption peak at 3700 cm−1, which is due to the OH dipole at ambient pressure. Over 3 GPa, brucite shows a pressure-induced absorption peak at 3650 cm−1. The pressure-induced peak can be assigned to a new OH dipole under pressure. The new peak indicates that brucite has a new
proton site under pressure and undergoes a high-pressure phase transition. From observations of the pressure-induced peak
under various P–T condition, a stable region of the high-pressure phase was determined. The original peak shifts to lower wavenumber at −0.25 cm−1 GPa−1, while the pressure-induced peak shifts at −5.1 cm−1 GPa−1. These negative dependences of original and pressure-induced peak shifts against pressure result from enhanced hydrogen bond
by shortened O–H···O distance, and the two dependences must result from the differences of hydrogen bond types of the original
and pressure-induced peaks, most likely from trifurcated and bent types, respectively. Under high pressure and high temperature,
the pressure-induced peak disappears, but a broad absorption band between 3300 and 3500 cm−1 was observed. The broad absorption band may suggest free proton, and the possibility of proton conduction in brucite under
high pressure and temperature.
Received: 16 July 2001 / Accepted: 25 December 2001 相似文献
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Hailong Lu Tatsuji Kawasaki Toshiyasu Ukita Igor Moudrakovski Tetsuya Fujii Satoshi Noguchi Tadaaki Shimada Masaru Nakamizu John Ripmeester Chris Ratcliffe 《Marine and Petroleum Geology》2011,28(10):1801-1805
Except for those occurring at seafloor, most of natural gas hydrate form in sediments and are subject to the influence of sediment. Among these factors, the particle size effect on hydrate saturation level in sediment have been studied with a series of silica sands with various sizes, and the results obtained clearly indicate that particle size does play an important role in affecting the saturation level of hydrate in sediments. The proton relaxation times of water confined in the same series of silica sands, which were determined with NMR measurement, show logarithmic relationship with particle size. By comprehensive consideration of the results of hydrate saturation and water proton relaxation times, the particle size effect observed is tentatively explained by the water availability for hydrate formation in sediments. 相似文献