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A Study of High-Temperature and High-Pressure Experiment of Correlativity between Deformational System of Au-Bearing Rocks and Element Adjustment 被引量:2
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作者 DONG Faxian LI Zhongjian +1 位作者 CHEN Bailin WANG Jianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期40-46,共7页
Modelling of migration and accumulation of elements Au and Ag in rocks under temperatures of 350–450°C and a confining pressure of 300 MPa and axial pressure of 100–150 MPa is conducted. It is found that the co... Modelling of migration and accumulation of elements Au and Ag in rocks under temperatures of 350–450°C and a confining pressure of 300 MPa and axial pressure of 100–150 MPa is conducted. It is found that the contents of gold and silver get higher in metallic sulphides such as pyrite, chalcopyrite and sphalerite as well as in quartz and muscovite, and get lower in chlorite, biotite, seriate, albite and calcite, showing that tectono-dynamics is one of the important factors for petrogenesis and metallogenesis. 展开更多
关键词 Au-bearing rocks element adjustments high-temperature and high-pressure experiment tectono-petrogenesis tectono-metallogenesis
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An experimental study of interaction between pure water and alkaline feldspar at high temperatures and pressures 被引量:1
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作者 Tao Li Heping Li Liping Xu 《Acta Geochimica》 EI CAS CSCD 2018年第1期60-67,共8页
Due to the important scientific significance of the interaction between alkaline feldspar and high-temperature and high-pressure fluids. We have conducted a series of autoclave experiments of feldspar dissolution and ... Due to the important scientific significance of the interaction between alkaline feldspar and high-temperature and high-pressure fluids. We have conducted a series of autoclave experiments of feldspar dissolution and secondary mineral precipitation in conditions of 250–500℃, 8-50 MPa, and pH = 3.0 and 5.5. Based on the interaction experiments between alkaline feldspar and fluid of high-temperatures and high-pressures, we get the main results as follows:(1) The law that people have grasped below the critical point about the influence of temperature, pressure, and pH value on the alkaline feldspar dissolution behavior is still held above the critical point.(2) Due to the experimental techniques of autoclave flip 180°—sharp quenching and based on electron microprobe analysis of mineral new formed, theoretical analysis has determined that the new altered minerals distributed on the island dissolution surface of feldspar are products of precipitation on a feldspar surface after saturation of the relative ion concentration in water fluid. 展开更多
关键词 Alkaline feldspar AUTOCLAVE high-temperature and high-pressure experiments
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The Research Status and Major Problems of High Temperature and High Pressure Experiment on Petrogenesis and mineralization
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作者 ZHANG Yan HAN Runsheng +1 位作者 WEI Pingtang ZHOU Gaoming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期296-297,共2页
1 Introduction In contrast,1experimental geochemistry is a young subject,but in recent years,the research on experiment of high temperature and high pressure has become an important branch in the parallel subjects of ... 1 Introduction In contrast,1experimental geochemistry is a young subject,but in recent years,the research on experiment of high temperature and high pressure has become an important branch in the parallel subjects of traditional mineralogy,petrology,geochemistry and geophysics.It is not only an important and essential way and window to understand geological processes in depth and geological 展开更多
关键词 In ZHANG The Research Status and Major Problems of high temperature and high Pressure experiment on Petrogenesis and mineralization high
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Study of corrosion behavior of labeling medium on Fe-36%Ni cold-rolled strip used in LNG carriers in high-temperature and high-humidity environment
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作者 WANG Xueting LV Jiansheng TIAN Yuxin 《Baosteel Technical Research》 CAS 2020年第1期39-43,共5页
To fulfill the high-quality surface requirements of the Fe-36% Ni cold-rolled strip used in liquid natural gas carriers,corrosion tests were conducted on alloy surfaces using ink media with different composition in hi... To fulfill the high-quality surface requirements of the Fe-36% Ni cold-rolled strip used in liquid natural gas carriers,corrosion tests were conducted on alloy surfaces using ink media with different composition in hightemperature and high-humidity conditions.The results show that the Cl^-content in ink is the main cause of surface corrosion of Fe-36%Ni alloy at 95%RH and 50℃ Cl^- penetrates the passivation film,causing pitting on the surface.This corrosive material primarily comprises elements Fe and O.After 120 h of high temperature and high humidity,pitting had occurred on the surface,which was characterized by irregularly distributed areas of bright red filamentous corrosion.With time,the corrosion gradually deepened and expanded to nearby areas.However,when the ink medium contained no Cl^-,no corrosion was found on the alloy surface.As such,during the production of Fe-36%Ni material and its application in LNG shipbuilding,care must be taken in the selection of the marker or medium that will come into contact with the strip surface to ensure that it contains no corrosive ions like Cl^-. 展开更多
关键词 corrosion Cl^- Fe-36%Ni high temperature and high humidity LNG
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Experimental study on liquid immiscibility of lamprophyre-sulfide melt at high temperature and high pressure and its geological significance
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作者 LI Bo HUANG Zhilong ZHU Chengming 《Chinese Journal Of Geochemistry》 EI CAS 2009年第2期198-203,共6页
With lamprophyre and pyrite from the Laowangzhai gold deposit, Yunnan Province, China, as starting materials, and at pressures from 1.5 to 3.0 GPa and temperatures from 1160 to 1560℃ , an experimental study was carri... With lamprophyre and pyrite from the Laowangzhai gold deposit, Yunnan Province, China, as starting materials, and at pressures from 1.5 to 3.0 GPa and temperatures from 1160 to 1560℃ , an experimental study was carried out on the liquid immiscibility of lamprophyre-sulfide melt at high temperature and ultra-high pressure in the DS-29A cubic 3600T/6-type high pressure apparatus. Results showed that the liquid immiscibility of lampro-pyre-sulfide melt in the magmatic system would happen during the early magmatic evolution (high temperature and high pressure conditions) and was controlled by temperature and pressure. The sulfide melt which was separated from the lamprophyric melt would make directional movement in the temperature and pressure field and assemble in the low-temperature and low-pressure region. Because the density of SM is higher than that of the lamprophyric melt, the former would gather together at the bottom of the magma chamber and there would exist a striking boundary between the two melts. On the other hand, the results also suggested that there would be little possibility for lampro-phyric magma to carry massive gold, and lamprophyres can't provide many of oreforming materials (Au) in the processes of gold mineralization. 展开更多
关键词 液态不混溶 高温高压 硫化物 煌斑岩 地质意义 熔体 液体 试验
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Experimental analysis of high temperature capacitance variance of MLCC
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作者 王锋 赵河明 《Journal of Measurement Science and Instrumentation》 CAS 2014年第1期29-31,共3页
High temperature capacitance variance of multi-layer ceramic capacitor (MLCC) is researched.Combined with the characteristics of MLCC,the application of MLCC in fuze is proposed,and the temperature stability of MLCC... High temperature capacitance variance of multi-layer ceramic capacitor (MLCC) is researched.Combined with the characteristics of MLCC,the application of MLCC in fuze is proposed,and the temperature stability of MLCC is also discussed.The experimental results indicate that the capacitance of low frequency MLCC is largely affected by temperature. 展开更多
关键词 temperature characteristics research high temperature failure high temperature experiment multi-layer ceramic capacitor (MLCC)
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An Experimental Study on the Drag Property of High-Temperature Particles Falling into Cold Liquid Pool 被引量:1
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作者 李小燕 匡波 +1 位作者 杨燕华 徐济鋆 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期58-62,共5页
This experiment is to study the special resistant induced by the high-speed evaporation surrounding themoving high-temperature particles. An observable equipment was designed, in which the first 11 experiments wereper... This experiment is to study the special resistant induced by the high-speed evaporation surrounding themoving high-temperature particles. An observable equipment was designed, in which the first 11 experiments wereperformed by pouring one or several Zirconia spheres with various high-temperature and a diameter of 3~ 10 mminto a water pool. The particles falling-down speeds were recorded by high-speed photographic instrumentation,and pressures and water temperatures were measured. A comparison between the experiments with cold and hotspheres respectively, employing three different sphere types each, was presented. The experimental data, com-pared with the theory of the evaporation drag model, are nearly identical. 展开更多
关键词 vapor explosion high temperature particles contact with low temperature liquid evaporation drag model observable experiment equipment
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Impact of Relative Humidity of Supply Gas on Temperature Distributions in Single Cell of Polymer Electrolyte Fuel Cell When Operated at High Temperature 被引量:2
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作者 Akira Nishimura Masato Yoshimura +2 位作者 Satoru Kamiya Masafumi Hirota Eric Hu 《Journal of Energy and Power Engineering》 2017年第11期706-718,共13页
For improving the performance of stationary PEFC (polymer electrolyte fuel cell) system, the cell operating temperature up to 90℃ will be preferred in Japan during the period from 2020 to 2030. To understand the op... For improving the performance of stationary PEFC (polymer electrolyte fuel cell) system, the cell operating temperature up to 90℃ will be preferred in Japan during the period from 2020 to 2030. To understand the operation of the PEFC system under relatively high temperature conditions, detail heat and mass transfer analysis is required. The purpose of this study is to analyze the impact of relative humidity of supply gas on temperature distribution on the backside of separator in single ceil of PEFC using Nation membrane at higher temperature e.g. 90℃. The in-plane temperature distribution when power was being generated was measured using thermograph with various relative humidity of supply gases. It was found that the in-plane temperature distribution at the anode was more even than that at the cathode irrespective of the relative humidity of supply gas at the anode and the cathode. The temperature elevated along gas flow through the gas channel at the cathode irrespective of relative humidity of supply gas at the anode and the cathode. The in-plane temperature distribution at the cathode was narrower with the increase in Tini irrespective of relative humidity of supply gas at the cathode, while it was not observed when changing the relative humidity of supply gas at the anode. When the relative humidity of supply gas at cathode decreased, the in-plane temperature distribution at the anode was wider compared to decreasing the relative humidity of supply gas at the anode. The study concluded that the impact of relative humidity of supply gas at both anode and cathode had little impact on the in-plane temperature distribution at the cathode. 展开更多
关键词 PEFC temperature distribution high temperature operation relative humidity.
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Compressional elastic wave velocities of serpentinized pyroxenite at high pressures and high temperatures and its geological significance
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作者 刘巍 杜建国 +2 位作者 白利平 谢鸿森 郭捷 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第4期456-461,共6页
Center for Analysis and Prediction, China Seismological Bureau, Beijing 100036, China 2) Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
关键词 high pressures and high temperatures experiment compressional wave velocity dehydration of serpentine rock fabric
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Temperature in High Temperature SHPB Experiments
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作者 邓志方 谢若泽 +2 位作者 颜怡霞 李思忠 黄西成 《Transactions of Tianjin University》 EI CAS 2008年第B10期536-539,共4页
As an experimental technique, it’s desired that the temperature in specimen is uniform in high temperature split Hopkinson pressure bar (SHPB) experiments. However, the temperature in specimen decreases and the tempe... As an experimental technique, it’s desired that the temperature in specimen is uniform in high temperature split Hopkinson pressure bar (SHPB) experiments. However, the temperature in specimen decreases and the temperature of bars increases when specimen starts to contact with bars, which induces the nonuniform temperature distribution in specimen, and may result in inac-curacy of experimental results. In this paper, the temperature distributions of specimen and bars in high temperature SHPB experiments were investigated while the specimen was heated alone. Firstly, the temperature history of specimen was measured at different initial temperatures by ex-periments, then simulation was carried out. Simulation results were consistent with experimental results by adjusting the thermal contact coefficient between specimen and bars. By this way, the thermal contact coefficient and simulation results were validated, and the proper cold contact times of specimen and bars in high temperature SHPB experiments were discussed. Finally, the results were compared with those in references. 展开更多
关键词 high temperature SHPB experiment heat transfer thermal contact coefficient cold contact time
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The Observation of Blood Biochemistry and HSP72 Expression Changing Rules in Peripheral Blood of Flying-saucer-athletes under High Temperature Training
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作者 Jian Shen Feng Xu +1 位作者 Bin Jin Rongquan Zhang 《Journal of Integrative Medicine(双语)》 2020年第2期8-11,共4页
Objective:To study the effect of training under high temperature on blood and heat shock protein 72(HSP72)expression of flying saucer athletes.Methods:The numbers of training group and control group are 30.Twenty-four... Objective:To study the effect of training under high temperature on blood and heat shock protein 72(HSP72)expression of flying saucer athletes.Methods:The numbers of training group and control group are 30.Twenty-four flying saucer athletes in Zhejiang province were selected and randomly divided into training group and control group,15 in each group.Peripheral venous blood of each group was taken before and after the experiment.The HSP72 content of lymphocyte,blood routine and biochemical indexes were measured respectively.Results:There was significant difference in white blood cell in training group count before and after the experiment(P<0.05).The expression of HSP72 and the white blood cell in training group was higher than that control group(P<0.05).Conclusions:Organism could be affected and turned to stress state due to training under high temperature.It is necessary to provide the safeguard for the flying saucer athletes under high temperature in order to prevent the damage. 展开更多
关键词 Flying Saucer Athletes Blood routine experiment Biochemical index Heat shock protein 72 Training under high temperature
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Effects of high temperature and high relative humidity drying on moisture distribution,starch microstructure and cooking characteristics of extruded whole buckwheat noodles
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作者 Linghan Meng Xuyang Sun +1 位作者 Yan Zhang Xiaozhi Tang 《Journal of Future Foods》 2024年第2期159-166,共8页
Drying is a key step in starch noodle production.The effects of high temperature(60,70,80°C)and high relative humidity(65%,75%,85%)drying(HTHD)on the moisture distribution,starch microstructure and cooking charac... Drying is a key step in starch noodle production.The effects of high temperature(60,70,80°C)and high relative humidity(65%,75%,85%)drying(HTHD)on the moisture distribution,starch microstructure and cooking characteristics of extruded whole buckwheat noodles were investigated.Compared to the conventional hot-air drying(CHAD)at 40°C,the increase in drying temperature(60–80°C)and the decrease in relative humidity(85%–65%)significantly improved drying efficiency of the extruded noodles.By adjusting drying temperature and relative humidity,the rate of moisture migration in noodles and phase transition of starch could be appropriately controlled.The optimum drying parameters(T70H75,70°C drying temperature and 75%relative humidity)showed smooth and dense network structure,resulting in the lowest cooking loss(6.61%),broken rate(0%),highest hardness(1695.17 g)and springiness(0.92).However,the total flavonoid content(TFC)and the total phenolic content(TPC)reduced by 6.81%–28.50%and 7.19%–53.23%in contrast to CHAD,and the color of buckwheat noodles became darker through HTHD.These findings showed the potential of HTHD for increasing drying efficiency and improving buckwheat noodle quality.The appropriate drying parameters could maintain a balanced relationship between moisture migration in noodles and phase transition of starch,which resulted in better cooking quality for extruded whole buckwheat noodles.Such a study is valuable for regulating the process conditions of buckwheat-based foods and promoting its commercial utilization. 展开更多
关键词 Extruded whole buckwheat noodle high temperature and high relative humidity drying Moisture distribution Starch microstructure Cooking characteristics
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Effects of Extreme Air Temperature and Humidity on the Insecticidal Expression Level of Bt Cotton 被引量:12
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作者 CHENYuan WEN Yu-jin +5 位作者 CHEN Yuan John Tom Cothren ZHANG Xiang WANG Yong-hui WilliamA Payne CHEN De-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第11期1836-1844,共9页
The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringie... The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringiensis (Bt) cotton. The unstable resistance of Bt cotton to bollworms has been correlated with the reduced expression of CrylAc δ-endotoxin. The objective of this study was to investigate the effects of combined temperature and relative humidity stresses on the leaf CrylAc insecticidal protein expression during critical developmental stages. The study was undertaken on two transgenic cotton cultivars that share same parental background, Sikang 1 (a conventional cultivar) and Sikang 3 (a hybrid cultivar), during the 2007 and 2008 growing seasons at the Yangzhou University Farm, Yangzhou, China. The study was arranged with two factors that consisted of temperature (two levels) and relative humidity (three levels). The six T/RH treatments were 37℃/95%, 37℃/70%, 37℃/50%, 18℃/95%, 18℃/70%, and 18℃/50%. In 2007, the six treatments were imposed to the plants at peak flowering stage for 24 h; in 2008, the six treatments were applied to the plants at peak square, peak flowering, and peak boll stages for 48 h. The results of the study indicated that the leaf insecticidal protein expression in CrylAc was significantly affected by extreme temperature only at peak flowering stage, and by both extreme temperature and relative humidity during boll filling stage. The greatest reductions were observed when the stresses were applied at peak boll stage. In 2008, after 48 h stress treatment, the leaf Bt endotoxin expression reduced by 25.9-36.7 and 23.6-40.5% at peak boll stage, but only by 14.9-26.5 and 12.8-24.0% at peak flowering stage for Sikang 1 and Sikang 3, respectively. The greatest reduction was found under the low temperature combined with low relative humidity condition for both years. It is believed that the temperature and relative humidity stresses may be attributed to the reduced efficacy of Bt cotton in growing conditions in China, where extreme temperatures often increase up to 35-40℃ and/or decrease down to 15-20℃, and relative humidity may reach to 85-95% and/or reduce to 40-55% during the cotton growing season. 展开更多
关键词 Bt cotton high temperature low temperature relative humidity CryIAc protein
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Influence Factors of Audible Noise Caused by Corona Discharge on UHVDC Transmission Lines Under High Altitude Condition 被引量:4
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作者 TIAN Feng YU Zhanqing +3 位作者 ZENG Rong LIU Lei LI Min LI Ruihai 《高电压技术》 EI CAS CSCD 北大核心 2012年第12期3125-3132,共8页
关键词 高压直流输电线路 电晕放电 影响因素 噪声 高海拔 高压直流输电工程 绝对湿度 电压升高
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Model Simulation of Artificial Heating of the Daytime High-Latitude F-Region Ionosphere by Powerful High-Frequency Radio Waves 被引量:1
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作者 Galina Mingaleva Victor Mingalev 《International Journal of Geosciences》 2014年第4期363-374,共12页
The large-scale disturbance of the spatial structure of the daytime high-latitude F-region ionosphere, caused by powerful high-frequency radio waves, pumped into the ionosphere by a groundbased ionospheric heater, is ... The large-scale disturbance of the spatial structure of the daytime high-latitude F-region ionosphere, caused by powerful high-frequency radio waves, pumped into the ionosphere by a groundbased ionospheric heater, is studied with the help of the numerical simulation. The mathematical model of the high-latitude ionosphere, developed earlier in the Polar Geophysical Institute, is utilized. The mathematical model takes into account the drift of the ionospheric plasma, strong magnetization of the plasma at F-layer altitudes, geomagnetic field declination, and effect of powerful high-frequency radio waves. The distributions of the ionospheric parameters were calculated on condition that an ionospheric heater, situated at the point with geographic coordinates of the HF heating facility near Tromso, Scandinavia, has been operated, with the ionospheric heater being located on the day side of the Earth. The results of the numerical simulation indicate that artificial heating of the ionosphere by powerful high-frequency waves ought to influence noticeably on the spatial structure of the daytime high-latitude F-region ionosphere in the vicinity of the ionospheric heater. 展开更多
关键词 high-LATITUDE IONOSPHERE Active experiments Modeling and Forecasting Plasma temperature and Density
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Mixing processes and patterns of fluids in alkane-CO_(2)-water systems under high temperature and high pressure——Microscopic visual physical thermal simulations and molecular dynamics simulations
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作者 Guanghui YUAN Shuqi WU +3 位作者 Yingchang CAO Zihao JIN Keyu LIU Yanzhong WANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第7期1622-1646,共25页
Various types of geofluids exist in deep and ultra-deep layers in petroliferous basins.The geofluids are much more active under high-temperature and high-pressure(HTHP)conditions,but their properties are unclear.We si... Various types of geofluids exist in deep and ultra-deep layers in petroliferous basins.The geofluids are much more active under high-temperature and high-pressure(HTHP)conditions,but their properties are unclear.We simulated the mixing of different fluids in CH_(4)/C_(3)H_(8)/C_(6)H_(14)/C_(8)H_(18)-water systems and C_(6)H_(14)/C_(8)H_(18)-CO_(2)-H_(2)O systems at temperatures of 25℃ to 425℃ and pressures of 5 MPa to 105 MPa,using an in-situ micron quartz capillary tube thermal simulation system and molecular dynamics numerical simulation software.The mixing processes,patterns,and mechanisms of various fluids were analyzed at microscale under increasing temperature and pressure conditions.The results show that the miscibility of fluids in the different alkane-H_(2)O and alkane-CO_(2)-H_(2)O systems is not instantaneous,but the miscibility degree between different fluid phases increases as the temperature and pressure rise during the experiments.The physical thermal experiments(PTEs)show that the mixing process can be divided into three stages:initial miscibility,segmented dynamic miscibility,and complete miscibility.The molecular dynamics numerical simulations(MDNSs)indicate that the mixing process of fluids in the alkane-H_(2)O and alkane CO_(2)-H_(2)O systems can be divided into seven and eight stages,respectively.The carbon number affects the miscibility of alkanes and water,and the temperature and pressure required to reach the same miscibility stage with water increase with the carbon number(C_(3)H_(8),C_(6)H_(14),CH_(4),C_(8)H_(18)).CO_(2) has a critical bridge role in the miscibility of alkanes and water,and its presence significantly reduces the temperatures required to reach the initial,dynamic,and complete miscibility of alkanes and water.The results are of great significance for analyzing and understanding the miscibility of geofluids in deep and ultra-deep HTHP systems. 展开更多
关键词 high temperature high pressure(HTHP) Alkane-H_(2)O-CO_(2)system Mixing of geofluids In-situ visualization thermal experiments Molecular dynamics numerical simulation
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燃氢燃机高温高湿透平耦合传热和冷却特性
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作者 任静 李雪英 +3 位作者 黄新宇 王文萍 孙鹏 李明飞 《动力工程学报》 CAS CSCD 北大核心 2024年第9期1416-1423,共8页
分析了燃氢燃机透平在导热/对流/辐射耦合作用下的流动传热和冷却特性,发展了能够计算高H_(2)O与CO_(2)分压比的灰气体加权和(WSGG)模型。结果表明:燃氢燃机工质中水蒸气含量增大导致金属壁面温度升高;加入辐射的影响后,H_(2)O和CO_(2)... 分析了燃氢燃机透平在导热/对流/辐射耦合作用下的流动传热和冷却特性,发展了能够计算高H_(2)O与CO_(2)分压比的灰气体加权和(WSGG)模型。结果表明:燃氢燃机工质中水蒸气含量增大导致金属壁面温度升高;加入辐射的影响后,H_(2)O和CO_(2)含量对传热的影响呈相反的结果,这主要是由于CO_(2)的对流传热能力强于H_(2)O,而H_(2)O的辐射能力强于CO_(2);在对流、导热、辐射3种传热方式都存在的燃氢透平冷却耦合系统中,气膜冷却的速度场几乎不受影响,而温度场则深受耦合及辐射的影响,所定义的耦合条件下气膜冷却效率能够表征燃氢条件下气膜的冷却性能,因此在燃氢燃机透平冷却的设计中,燃氢导致的热负荷恶化需纳入设计变量中。 展开更多
关键词 燃氢燃气轮机 透平 高温高湿 耦合传热 冷却特性 辐射
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世界典型高温地热田回灌经验及对谷露热田回灌井部署的启示
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作者 张松 郑冉 +7 位作者 郝伟林 胡先才 万汉平 胡志华 高洪雷 张健 吴儒杰 唐伟军 《世界核地质科学》 CAS 2024年第4期745-755,共11页
地热尾水回灌是地热田开发过程中必不可少的环节,对热田开发具有重要意义。对世界上不同类型高温地热田回灌策略进行系统梳理,发现不同类型地热田常采取不同的回灌策略:气相为主的气液两相地热田常进行内场回灌;液相为主的气液两相地热... 地热尾水回灌是地热田开发过程中必不可少的环节,对热田开发具有重要意义。对世界上不同类型高温地热田回灌策略进行系统梳理,发现不同类型地热田常采取不同的回灌策略:气相为主的气液两相地热田常进行内场回灌;液相为主的气液两相地热田和水热型地热田常采用内场回灌与外场回灌相结合的方式。重点分析与谷露地热田相似的美国Brady Hot Spring地热田、Beowawe地热田和中国羊易地热田三个水热型高温地热田在生产过程中的回灌情况,对上述地热田在回灌过程中的回灌距离、回灌深度及回灌后对热田生产的影响进行总结。上述地热田多采用同构造回灌的方式进行回灌;一般无特定的回灌距离,常采用内场回灌与外场回灌相结合的方式进行;回灌目的层常选择渗透性好的断裂构造;回灌深度以大于500 m的深层回灌为主。这些热田在回灌过程中,为了达到良好效果,需要平衡生产区的压力下降和热突破之间的关系。结合谷露地热田实际地质情况,认为谷露地热田应该采取同构造回灌,且采用内场回灌与外场回灌相结合的深层回灌方式。初步在热田生产区1 km以外的位置选择3片回灌区域。其中回灌1区是主要回灌区域,位于热田生产区的北侧约1~1.5 km范围内。为了防止发生热突破,需要在回灌井实施过程中,进行回灌试验,尽早确定回灌井与生产区之间的水力联系。 展开更多
关键词 西藏 高温地热田 回灌经验 谷露地热田 回灌井
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PVA-ECC高温冷却后力学特性与微观损伤机理
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作者 武芳文 何岚清 +3 位作者 段钧淇 王广倩 刘来君 杨飞 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第9期140-149,共10页
为研究工程水泥基复合材料(engineered cementitious composite,ECC)高温后的力学性能和微观特征,对ECC进行了高温后材料力学性能试验和微观特征观测。对常温(25℃)、200℃、300℃、400℃及500℃自然冷却和喷水冷却后的ECC试件开展了抗... 为研究工程水泥基复合材料(engineered cementitious composite,ECC)高温后的力学性能和微观特征,对ECC进行了高温后材料力学性能试验和微观特征观测。对常温(25℃)、200℃、300℃、400℃及500℃自然冷却和喷水冷却后的ECC试件开展了抗压和抗折性能试验,并结合扫描电镜分析了ECC微观结构损伤特征以及探究了ECC高温后损伤机理。实验结果表明:高温后ECC表面未发生剥落,500℃以内未见爆裂现象,随着温度升高,纤维由混凝土表面逐渐向内部熔化,且失水增多,最大烧失率13.9%;力学性能方面,ECC自然冷却后抗压强度随温度升高呈现先降低后升高再降低的现象,而喷水冷却后抗压强度随温度的升高单调降低,且强度降低显著;高温后抗折强度随温度升高逐步下降,自然冷却降低幅度较喷水冷却显著;结合微观结构变化,ECC经历高温时,纤维部分熔化导致纤维与基体的黏结性能减弱;随着温度升高水化产物之间逐渐呈现独立存在的分散体,但喷水冷却后未水化颗粒二次水化现象明显,使ECC抗折强度较自然冷却提升17%。ECC具有良好的热稳定性,且冷却方式影响ECC材料的表观特性、力学性能和微观特征。 展开更多
关键词 桥梁工程 力学特性 高温试验 ECC 微观结构 冷却方式
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高温高湿隧道工人劳动强度和劳动时间研究
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作者 于丽 唐永红 +2 位作者 路明 周振宇 张晨妍 《地下空间与工程学报》 CSCD 北大核心 2024年第5期1665-1675,共11页
当隧道穿越高温热泉断层破碎带时,施工人员将面临高温高湿环境,而钻爆法隧道施工工序复杂,劳动强度大,高湿环境对隧道人员的影响巨大。为保障隧道施工人员的安全健康,本文基于能量代谢率变化规律得到高温高湿环境隧道施工人员劳动强度... 当隧道穿越高温热泉断层破碎带时,施工人员将面临高温高湿环境,而钻爆法隧道施工工序复杂,劳动强度大,高湿环境对隧道人员的影响巨大。为保障隧道施工人员的安全健康,本文基于能量代谢率变化规律得到高温高湿环境隧道施工人员劳动强度修正等级和人体预测热应激修正模型,给出了高温高湿环境下隧道施工人员安全连续劳动时间建议,并在高温隧道进行了现场测试。结果表明:当温度大于30℃,湿度大于70%时,温度每增加4℃,或相对湿度每上升10%,隧道施工人员劳动强度等级约增加一级;当温度超过38℃,相对湿度大于90%或温度超过40℃,相对湿度大于70%时,所施工人员均应停止作业,现场测试结果表明人体热应激修正模型误差小于5%。 展开更多
关键词 高温高湿 隧道施工 劳动强度 劳动时间 施工安全
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