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The Wavelet Property of the Geomagnetic Anomaly Signal

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 244-248页

作者： Jiangfa L IN &Gang WANG&Saizhen ZHANG&Yaosong CHEN (Dept. of Mech.,Peking Univ.,Bei Jing 1 0 0 871 ,P.R.China) Department of Mechanics and Engineering Science Peking University Beijing 100871 China

In this study,wavelet analysis is utilized to analyze the geomagnetic signals for oil- gas exploration,in order to show the relation between the wavelet property of the geomagnetic signals and the underground treasure. At first,the global geomagnetic anomaly signal in the oil exploration is ***,with the wavelet theory the geomagnetic signals of an oil- gas field is *** preliminary wavelet analysis shows thatthe underground oil- gas location can be determined with the help of its regional high frequency signal distributions.

关键词： wavelet analysis geomagnetic anomaly high frequency

Liquid metal as energy transportation medium or coolant under harsh environment with temperature below zero centigrade

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Frontiers in Energy 2014年第1期8卷 49-61页

作者： Yunxia GA0 Lei WANG Haiyan LI Jing LIU Key Lab of Cryogenics and Beijing Key Lab of CryoBiomedicalEngineering Technical Institute of Physics and Chemistry ChineseAcademy of Sciences Beijing 100190 China Department of Biomedical Engineering School of Medicine TsinghuaUniversity Beijing 100084 China

The current highly integrated electronics and energy systems are raising a growing demand for more sophisticated thermal management in harsh environments such as in space or some other cryogenic environment. Recently, it was found that room temperature liquid metals （RTLM） such as gallium or its alloys could significantly reduce the electronics temperature compared with the conventional coolant, like water, oil or more organic fluid. However, most of the works were focused on RTLM which may subject to freeze under low temperature. So far, a systematic interpretation on the preparation and thermal properties of liquid metals under low temperature （here defined as lower than O^C） has not yet been available and related applications in cryogenic field have been scarce. In this paper, to promote the research along this important direction and to overcome the deficiency of RTLM, a comprehensive evaluation was proposed on the concept of liquid metal with a low melting point below zero centigrade, such as mercury, alkali metal and more additional alloy candidates. With many unique virtues, such liquid metal coolants are expected to open a new technical frontier for heat transfer enhancement, especially in low temperature engineering. Some innovative ways for making low melting temperature liquid metal were outlined to provide a clear theoretical guideline and perform further experiments to discover new materials. Further, a few promising applied situations where low melting temperature liquid metals could play irreplaceableroles were detailed. Finally, some main factors for optimization of low temperature coolant were summarized. Overall, with their evident merits to meet various critical requirements in modem advanced energy and power industries, liquid metals with a low melting temperature below zero centigrade are expected to be the next- generation high-performance heat transfer medium in thermal managements, especially in harsh environment in space.

关键词： liquid metal cryogenics low melting point,thermal management aircraft liquid cooling spaceexploration

Localized Electrochemical Impedance Spectroscopy Study on the Corrosion Behavior of Fe-Cr Alloy in the Solution with Cl^- and SO_4^(2-)

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 27-32页

作者： XIAO Kui ZHANG Xin D0NG Chaofang WEI Dan WANG Chen LI Xiaogang Advanced Material and Technology Institute University of Science&Technology BeijingBeijing 100083China Society Service Center China Association for Science and TechnologyBeijing 100081China Faculty of Metallurgical and Energy Engineering Kunmming University of Science and TechnologyKunming 650093China

The corrosion behaviors of Fe-Cr alloy under three different pH values solutions with C1- and SO42- were investigated by localized electrochemical impedance spectroscopy （LEIS） measurements and the corrosion products were analyzed by laser Raman spectrometry. The results show that the high corrosion resistance of Fe-Cr Alloy is attributed to a passive film which is formed more easily when the alloy contains a large quantity of Cr element. However, its corrosion resistance varies in the solutions with different pH values, especially in the initial corrosion. The average impedance values in neutral and alkaline solution are much higher than that in acidic solution because the passive film is more likely to dissolve in the acidic condition. Moreover, the destructive effect of C1- and SO42 ions on the passive film is also demonstrated in corrosion process through the change of the impedance value with the steeping time.

关键词： Fe-Cr Alloy localized electrochemical impedance spectroscopy (LEIS) corrosionproducts Raman spectroscopy

Responses of CO_2 in surface water in subtropical West Pacific to El Nio event

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Acta Oceanologica Sinica 2001年第1期20卷 39-50页

作者： Xing Runan 1, Ma Liming 2, Qiao Ran 2,Wang Zhanggui 21 .TrainingCenterofChineseMeteorologicalAdministration ,Beijing 10 0 0 81,China2 .NationalResearchCenterforMarineEnvironmentalForecasts ,StateOceanicAdministration ,Beijing 10 0 0 81,China

In order to investigate the relationships between the change of T CO 2 , Δ P CO 2 and SST, current, upwelling and biological activities during El Nio event in the subtropical Pacific, the responses of T CO 2 and Δ P CO 2 in surface water in the subtropical Pacific during El Nio and La Nina have been simulated using a three dimension carbon cycle model with biota pump. The results of numerical simulations show that T CO 2 in sea water increases with reducing of SST during mature phase of El Nio in the subtropical West Pacific . At the same period ,the Kuroshio in this region was weakened ,the zonal currents were divergence , the upwelling carried the water with high concentrations of CO 2 to the sea surface , so both of T CO 2 and Δ P CO 2 in surface water were increased . But T CO 2 and Δ P CO 2 were decreased during La Nina period. These simulated results confirmed the observations in 1982/1983 , 1986/1987 , 1991/1995 and 1997/1998 El Nio events .

关键词： CO 2 El Nio the subtropical West Pacific

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五个氨基酸磷光性质的研究

生物化学与生物物理进展 1997年第1期24卷 60-63页

作者：黄如衡军事医学科学院毒物药物研究所北京100850

研究了 5个氨基酸的磷光特性、光谱、寿命和最小检测量 .以色氨酸 (Trp)的磷光最强 ,在λex/λem=2 90 /4 38nm ,最小检测量为 1ng ,酪氨酸 (Tyr)其次 ( 2 84 /390nm)为Trp的 1 /1 0 ,苯丙氨酸 (Phe)在 2 76/386nm ,脯氨酸 (Pro)在 30 8... 详细信息

研究了 5个氨基酸的磷光特性、光谱、寿命和最小检测量 .以色氨酸 (Trp)的磷光最强 ,在λex/λem=2 90 /4 38nm ,最小检测量为 1ng ,酪氨酸 (Tyr)其次 ( 2 84 /390nm)为Trp的 1 /1 0 ,苯丙氨酸 (Phe)在 2 76/386nm ,脯氨酸 (Pro)在 30 8/4 54nm ,组氨酸 (His)在 32 0 /4 66nm ,其磷光只有Trp的 1 % .Phe与Trp磷光寿命最长 ,在 7s左右 ;His最短 ,只有 0 4 9s;Tyr 2 8s,Pro 1 34s.另外研究氨基酸在甲醇 ,乙醇 ,丙醇 ,丁醇中及pH对氨基酸磷光性质的影响 .还计算了Stokes位移能量及激化态 pK a

关键词：氨基酸膦光性质磷光

Clinical Application of Bioprosthesis in China:Current Status and Future

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Current Medical Science 2019年第4期39卷 523-525页

作者： Yin WANG Wei-wei JIANG Nian-guo D0NG Department of Cardiovascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

China is one of the countries which have a high incidence of heart valvular disease,but the use of biological valve is limited in China before because the majority of patients are young patients suffering from rheumatic heart *** biological valve has a good application prospect in *** the one hand,the new generation of biological valves have been significantly improved in the aspects of anti-calcification treatment,anti-metabolism,material quality control,valve frame mechanics design,and leaflet sewing technology,and the application effect is improved;on the other hand,surgeons should adapt to the new concept changes,and correctly understand and rationally apply biological valves,master valve repair,atrial fibrillation ablation and other techniques,combined with interventional,minimally invasive techniques,etc.,according to the specific conditions of the disease and choose the surgery type to ensure the patients5 long-term life quality.

关键词： biological valve valve surgery clinical application China

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细胞质膜微囊与信号转导

生物化学与生物物理进展 1997年第3期24卷 194-198页

作者：黄芬中国科学院生物物理研究所

细胞质膜微囊 (caveolae)为 50～ 1 0 0nm的小囊泡 ,它们以内陷形式连接在细胞质膜上 ,并广泛存在于各种类型的细胞 .早在 4 0多年前用透射电镜曾观察到此微囊结构 .细胞质膜微囊的功能为通过毛细管内皮细胞转运小分子及大分子以及具有... 详细信息

细胞质膜微囊 (caveolae)为 50～ 1 0 0nm的小囊泡 ,它们以内陷形式连接在细胞质膜上 ,并广泛存在于各种类型的细胞 .早在 4 0多年前用透射电镜曾观察到此微囊结构 .细胞质膜微囊的功能为通过毛细管内皮细胞转运小分子及大分子以及具有“液饮”作用 .最近实验表明。

关键词：细胞学细胞质膜微囊微囊蛋白信号转导

A GPA diagnostic system foraeroengine applications

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航空动力学报 2007年第6期22卷 898-908页

作者： Yi-Guang Li(School of Engineering,Cranfield University,Cranfield,Bedford MK43 0AL,England) School of Engineering Cranfield University England

In this research,a GPA(Gas Path Analysis) diagnostic system enhanced with GPA Index is described for gas path sensor and component fault diagnosis.A method of measurement correction is used in order that the measurement data obtained at un-standard ambient and operating conditions can be used for diagnostic *** developed diagnostic system has been implemented into a Cranfield University gas turbine performance and diagnostic analysis software PYTHIA for gas turbine performance degradation *** developed method and software have been applied to a model aero gas turbine engine to test the effectiveness of the *** analysis shows that the developed diagnostic system can diagnose degraded sensor and components effectively using performance deviation measured at un-standard ambient and operational ***,the idea of the diagnostic approach can be applied to different gas turbine engines.

关键词：航空发动机燃气涡轮诊断系统气体分解

A Study of the Lithic Assemblage from Zhoukoudian Locality 15

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人类学学报 2002年第S1期21卷 31-52页

作者： GAOXing (Institute of Vertebrate Paleontologyand Paleoanthropology ,Chinese Academy of Sciences P .O .Box 6 43,Beijing 10 0 0 4 4,P .R .China )

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关键词： 110 A Study of the Lithic Assemblage from Zhoukoudian Locality 15