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Molecular dynamics simulations of helium transport through inorganic mineral nanopores
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作者 Dandan SONG Ping GUAN +1 位作者 Chi ZHANG Jiahao REN 《Science China Earth Sciences》 2025年第1期237-252,共16页
Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration.To elucidate helium's transport dynamics within nanopores,we employed equilibrium and non-equilibr... Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration.To elucidate helium's transport dynamics within nanopores,we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores.We also introduced water and various gases,including hydrogen,methane,ethane,nitrogen,and carbon dioxide,into the nanopores to assess their influence on helium transport.Our findings indicate minimal helium adsorption on quartz pore surfaces.Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa,environmental factors markedly influence helium diffusion.Large pore sizes,high temperatures,and low gas pressures enhance helium desorption and facilitate faster diffusion.We observed a positive correlation between helium flow velocity and factors such as pore size,pressure gradient,and surface smoothness of the pores.Notably,the presence of pore water and carrier gases in quartz nanopores,which diffuse more slowly than helium,tends to reduce helium surface adsorption and slow its diffusion.Among the carrier gases studied,nitrogen showed similar adsorption capacity,diffusivity,and stability to helium,while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate,markedly differing from helium.Based on the simulation results,we concluded that water and carrier gases primarily function as transport mediums in helium migration,moving together with helium.Nitrogen,which shares similar properties with helium,effectively assists in this co-migration process.Conversely,carbon dioxide,due to its high adsorption capacity and slow diffusion,tends to be lost during co-migration.As a result,gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations.Additionally,the smaller pore sizes and higher gas pressures in caprocks can impede helium's diffusion,favoring its preservation in reservoirs.Moreover,the presence of water and carrier gases significantly obstructs these pores,further hindering helium's escape. 展开更多
关键词 helium transport Slit nanopores Molecular dynamics simulations DIFFUSION Flow carriers
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Co-doped BaFe_(2)As_(2) Josephson junction fabricated with a focused helium ion beam 被引量:1
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作者 陈紫雯 张焱 +6 位作者 马平 徐中堂 李宇龙 王越 路建明 马衍伟 甘子钊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期181-186,共6页
Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation ... Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation of high-quality iron pnictide Josephson junctions is of great importance.In this work,we have successfully fabricated Josephson junctions from Co-doped BaFe_(2)As_(2)thin films using a direct junction fabrication technique which utilizes high energy focused helium ion beam(FHIB).The electrical transport properties were investigated for junctions fabricated with various He^(+)irradiation doses.The junctions show sharp superconducting transition around 24 K with a narrow transition width of 2.5 K,and a dose correlated foot-structure resistance which corresponds to the effective tuning of junction properties by He^(+)irradiation.Significant J_c suppression by more than two orders of magnitude can be achieved by increasing the He^(+)irradiation dose,which is advantageous for the realization of low noise ion pnictide thin film devices.Clear Shapiro steps are observed under 10 GHz microwave irradiation.The above results demonstrate the successful fabrication of high quality and controllable Co-doped BaFe_(2)As_(2)Josephson junction with high reproducibility using the FHIB technique,laying the foundation for future investigating the mechanism of iron-based superconductors,and also the further implementation in various superconducting electronic devices. 展开更多
关键词 focused helium ion beam Co doped BaFe_(2)As_(2) Josephson junction
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BASIC REGULARITY OF PETROGENESIS AND METALLOGENESIS OF NANLING CRUST-DERIVED TYPE GRANITOIDS
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作者 LIU Jiayuan WANG Rongrong WU Guoquan(Guilin College of Technology, Guilin, Guangxi, China) 《Geotectonica et Metallogenia》 1997年第Z1期27-42,共16页
In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-... In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type granites.Tectonically,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history. 展开更多
关键词 source strata for magmatism endogenic metal crust-derived TYPE granite
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Evolution of helium bubbles in FeCoNiCr-based high-entropy alloys containing γ′ nanoprecipitates
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作者 冯婷 蒋胜明 +4 位作者 胡潇天 张子骏 黄子敬 董士刚 张建 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期491-500,共10页
A series of high-entropy alloys(HEAs) containing nanoprecipitates of varying sizes is successfully prepared by a non-consuming vacuum arc melting method.In order to study the irradiation evolution of helium bubbles in... A series of high-entropy alloys(HEAs) containing nanoprecipitates of varying sizes is successfully prepared by a non-consuming vacuum arc melting method.In order to study the irradiation evolution of helium bubbles in the FeCoNiCrbased HE As with γ' precipitates,these samples are irradiated by 100-keV helium ions with a fluence of 5 × 10^(20) ions/m^(2) at 293 K and 673 K,respectively.And the samples irradiated at room temperature are annealed at different temperatures to examine the diffusion behavior of helium bubbles.Transmission electron microscope(TEM) is employed to characterize the structural morphology of precipitated nanoparticles and the evolution of helium bubbles.Experimental results reveal that nanosized,spherical,dispersed,coherent,and ordered L1_(2)-type Ni_(3)Ti γ' precipitations are introduced into FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs by means of ageing treatments at temperatures between 1073 K and 1123 K.Under the ageing treatment conditions adopted in this work,γ' nanoparticles are precipitated in FeCoNiCr(Ni_(3)Ti)_(0.1) HE As,with average diameters of 15.80 nm,37.09 nm,and 62.50 nm,respectively.The average sizes of helium bubbles observed in samples after 673-K irradiation are 1.46 nm,1.65 nm,and 1.58 nm,respectively.The improvement in the irradiation resistance of FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs is evidenced by the diminution in bubbles size.Furthermore,the FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs containing γ' precipitates of 15.8 nm exhibits the minimum size and density of helium bubbles,which can be ascribed to the considerable helium trapping effects of heterogeneous coherent phase boundaries.Subsequently,annealing experiments conducted after 293-K irradiation indicate that HEAs containing precipitated phases exhibits smaller apparent activation energy(E_(a)) for helium bubbles,resulting in larger helium bubble size.This study provides guidance for improving the irradiation resistance of L1_(2)-strengthened high-entropy alloy. 展开更多
关键词 high-entropy alloys irradiation resistance coherent precipitates helium bubbles
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Genetic source,migration and accumulation of helium under deep thermal fluid activities:A case study of Ledong diapir area in Yinggehai Basin,South China Sea
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作者 FENG Ziqi HAO Fang +7 位作者 HU Lin HU Gaowei ZHANG Yazhen LI Yangming WANG Wei LI Hao XIAO Junjie TIAN Jinqiang 《Petroleum Exploration and Development》 SCIE 2024年第3期753-766,共14页
Based on the geochemical parameters and analytical data,the heat conservation equation,mass balance law,Rayleigh fractionation model and other methods were used to quantify the in-situ yield and external flux of crust... Based on the geochemical parameters and analytical data,the heat conservation equation,mass balance law,Rayleigh fractionation model and other methods were used to quantify the in-situ yield and external flux of crust-derived helium,and the initial He concentration and thermal driving mechanism of mantle-derived helium,in the Ledong Diapir area,the Yinggehai Basin,in order to understand the genetic source,migration and accumulation mechanisms of helium under deep thermal fluid activities.The average content of mantle-derived He is only 0.0014%,the ^(3)He/^(4)He value is(0.002–2.190)×10^(−6),and the R/Ra value ranges from 0.01 to 1.52,indicating the contribution of mantle-derived He is 0.09%–19.84%,while the proportion of crust-derived helium can reach over 80%.Quantitative analysis indicates that the crust-derived helium is dominated by external input,followed by in-situ production,in the Ledong diapir area.The crust-derived helium exhibits an in-situ 4 He yield rate of(7.66–7.95)×10^(−13)cm^(3)/(a·g),an in-situ 4 He yield of(4.10–4.25)×10^(−4)cm^(3)/g,and an external 4 He influx of(5.84–9.06)×10^(−2)cm^(3)/g.These results may be related to atmospheric recharge into formation fluid and deep rock-water interactions.The ratio of initial mole volume of 3 He to enthalpy(W)is(0.004–0.018)×10^(−11) cm^(3)/J,and the heat contribution from the deep mantle(X_(M))accounts for 7.63%–36.18%,indicating that deep hot fluid activities drive the migration of mantle-derived 3 He.The primary helium migration depends on advection,while the secondary migration is controlled by hydrothermal degassing and gas-liquid separation.From deep to shallow layers,the CO_(2/3) He value rises from 1.34×10^(9)to 486×10^(9),indicating large amount of CO_(2)has escaped.Under the influence of deep thermal fluid,helium migration and accumulation mechanisms include:deep heat driven diffusion,advection release,vertical hydrothermal degassing,shallow lateral migration,accumulation in traps far from faults,partial pressure balance and sealing capability. 展开更多
关键词 deep thermal fluid helium genetic source migration and accumulation mechanism Yinggehai Basin
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Atomistic study on the microscopic mechanism of grain boundary embrittlement induced by small dense helium bubbles in iron
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作者 Lei Peng Yong-Jie Sun +3 位作者 Jing-Yi Shi Yi-Fei Liu Shang-Ming Chen Liu-Liu Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期84-95,共12页
The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion reactors.In order to eluc... The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion reactors.In order to elucidate the susceptibility of different grain boundaries(GBs)to helium-induced embrittlement,the tensile fracture processes of 10 types of GBs with and without helium bubbles in body-centered cubic(bcc)iron at the relevant service temperature of 600 K were investigated via molecular dynamics methods.The results indicate that in the absence of helium bubbles,the GBs studied here can be classified into two distinct categories:brittle GBs and ductile GBs.The atomic scale analysis shows that the plastic deformation of ductile GB at high temperatures originates from complex plastic deformation mechanisms,including the Bain/Burgers path phase transition and deformation twinning,in which the Bain path phase transition is the most dominant plastic deformation mechanism.However,the presence of helium bubbles severely inhibits the plastic deformation channels of the GBs,resulting in a significant decrease in elongation at fractures.For bubble-decorated GBs,the ultimate tensile strength increases with the increase in the misorientation angle.Interestingly,the coherent twin boundary∑3{112}was found to maintain relatively high fracture strength and maximum failure strain under the influence of helium bubbles. 展开更多
关键词 helium bubble Grain boundary EMBRITTLEMENT Reduced activation ferritic martensitic steel Molecular dynamics Bain path
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Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton
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作者 Zihan Gao Zhi Chen +5 位作者 Hongyi He Zhaofei Liu Chang Lu Hanyu Wang Yili Luo Ying Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期23-33,共11页
At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of... At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of He generation rate and the geochemical characteristics of the produced gas, both the similarities and differences between natural gas and He resources in the Bohai Bay, Ordos and the surrounding Songliao Basin are compared and analyzed, discussing the main controlling factors of helium resources in the three main petroliferous basins of the North China Craton. It is found that the three basins of Bohai Bay, Ordos and Songliao have similar characteristics of source rocks, reservoirs and cap rocks, that's why their methane resource characteristics are essentially the same. The calculated ~4He generation per cubic metamorphic crystalline basement in the three basins is roughly equivalent, which is consistent with the measured He resources, and it is believed that the ~4He of radiogenic from the crust is the main factor controlling the overall He accumulation in the three basins;there is almost no contribution of the mantle-derived CH_4, which suggests that the transport and uplift of mantle-derived ~3He carried by the present-day magmatic activities along the deep-large faults is not the main reason for the mantle-derived ~3He mixing in the basins. Combined with the results of regional volcanic and geophysical studies,it is concluded that under the background of the destruction of North China Craton, magma intrusion carried a large amount of mantle-derived material and formed basic volcanic rocks in the Bohai Bay Basin and Songliao Basin, which replenished mantle-derived ~3He for the interior of the basins, and that strong seismic activities in and around the basins also promoted the upward migration of mantle source ~3He. This study suggests that the tectonic zone with dense volcanic rocks in the Cenozoic era and a high incidence of historical strong earthquakes history may be a potential area for helium resource exploration. 展开更多
关键词 helium Bohai Bay Basin destruction of the North China Craton FAULT Cenozoic volcanic rocks strong earthquake activity
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联产轻烃回收与LNG提氦工艺设计与模拟
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作者 肖荣鸽 李雨泽 +1 位作者 刘亚龙 刘鸿嘉 《现代化工》 CAS 北大核心 2025年第1期239-244,共6页
为了降低单一工艺中提氦的能量消耗及设备成本、使氮气循环膨胀制冷提供的冷量得到更加充分的利用,将自产冷剂制冷+膨胀制冷+冷箱集成换热的直接换热(DHX)轻烃回收工艺与天然气低温提氦工艺相结合,设计出一种可以同时生产C_(3)+、粗氦以... 为了降低单一工艺中提氦的能量消耗及设备成本、使氮气循环膨胀制冷提供的冷量得到更加充分的利用,将自产冷剂制冷+膨胀制冷+冷箱集成换热的直接换热(DHX)轻烃回收工艺与天然气低温提氦工艺相结合,设计出一种可以同时生产C_(3)+、粗氦以及LNG的联产工艺。通过对关键参数影响因素分析,确定了膨胀机出口的压力为1.2 MPa、DHX塔顶回流温度为-70℃、一级提氦塔进料温度为-50℃、压缩泵出口压力为5 MPa、低温分离器进料温度为35℃、制冷剂流量为4000 kmol/h。模拟计算得出,联产工艺C_(3)+回收率为78.95%、粗氦回收率为93.77%、粗氦浓度为60.43%、LNG产量为663.84 kmol/h。联产工艺与单一工艺相比总压缩机能耗降低了12.95%、单位综合能耗降低14.10%。研究表明,联产轻烃回收与LNG提氦工艺在能耗和投资成本方面具有较大优势,具有一定的经济价值。 展开更多
关键词 轻烃回收 提氦 HYSYS 氮气膨胀 能耗
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负氦离子束产生技术研究
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作者 陈浩南 崔保群 +9 位作者 唐兵 陈立华 马瑞刚 马鹰俊 马燮 张一帆 赵建革 王云峰 杨超 于荣凯 《原子能科学技术》 北大核心 2025年第1期205-212,共8页
串列加速器可产生MeV级的正离子束,其中He离子束可用于离子束分析、离子注入等实验研究和工业应用,是串列加速器不可或缺的一种离子束流。串列加速器要求负离子注入,负氦离子束是串列加速器产生MeV级He离子束的关键。由于基态He原子电... 串列加速器可产生MeV级的正离子束,其中He离子束可用于离子束分析、离子注入等实验研究和工业应用,是串列加速器不可或缺的一种离子束流。串列加速器要求负离子注入,负氦离子束是串列加速器产生MeV级He离子束的关键。由于基态He原子电子亲合能小于0,无法直接在离子源中产生和引出He-离子束,只能通过连续两次的电荷交换产生,所以He^(-)离子束被认为是最难产生的负离子束之一。针对串列加速器He^(-)离子的注入需求,研究设计了一款负氦离子源,使用多峰会切场离子源电离产生He^(+)离子,注入电荷交换器中,通过电荷交换产生He^(-)离子束。模拟了多峰会切场离子源的磁场位形和粒子轨迹,验证了多峰场构型对电子约束的作用,能维持离子源稳定放电。设计了电荷交换器结构,考虑了热平衡状态时的温度分布,确保了金属Cs作为电荷交换介质的长期稳定运行。基于中国原子能科学研究院1.7 MV串列加速器低能束流线平台开展了产生负氦离子束的实验,优化了离子束的聚焦传输参数,测量了电荷交换器工作温度和He^(+)离子注入能量对He^(-)离子产率的影响。实验中测得最大He^(-)离子产率为1.76%±0.03%,调节离子源放电参数得到了最大1.5μA的He^(-)离子束流,基本满足串列加速器的注入需求。后续进一步改进离子源,增强放电强度,提高引出He^(+)离子流强,有望进一步提升He^(-)离子流强。该研究为国产负氦离子源的发展提供了重要技术支持,对实现串列加速器技术的自主可控具有重要意义。 展开更多
关键词 负氦离子束 离子源 电荷交换 负氦离子产率
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低品位含氦天然气氦气提浓工艺的研究
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作者 范瑛琦 李保军 盖丽梅 《现代化工》 北大核心 2025年第2期232-236,共5页
对近年来常见的深冷、膜+深冷、膜分离3种含氦天然气提浓工艺进行了模拟,希望找到更为经济的氦气提浓方式,从而为国内低品位含氦气田的经济利用提供有益的参考。模拟发现,对于氦气体积分数为0.0416%的天然气,膜分离技术可以大幅降低氦... 对近年来常见的深冷、膜+深冷、膜分离3种含氦天然气提浓工艺进行了模拟,希望找到更为经济的氦气提浓方式,从而为国内低品位含氦气田的经济利用提供有益的参考。模拟发现,对于氦气体积分数为0.0416%的天然气,膜分离技术可以大幅降低氦气提浓过程的能耗,3种提浓工艺中,膜分离工艺单耗最低、氦气收率最高。因此,目前对于低品位含氦天然气提浓过程,膜分离工艺是最为适合的提浓工艺。 展开更多
关键词 天然气 氦气 深冷 膜分离
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郯庐断裂带临沂段地热水溶性氦气的分布特征及成因分析
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作者 李兆营 张建太 +7 位作者 李付全 胡彩萍 康鹏宇 肖丙建 胡自远 程龙 周亮宇 路晓平 《地质论评》 北大核心 2025年第1期328-340,共13页
绝大部分氦气矿藏赋存在油气矿藏中,对于地热井、温泉井中水溶性氦气的研究相对较少,郯庐断裂带(郯城—庐江断裂带)作为一条巨型走滑断裂,分布多处含氦气的地热井、温泉,而查明地热水中氦气的来源显得尤为重要。笔者等利用在郯庐断裂带... 绝大部分氦气矿藏赋存在油气矿藏中,对于地热井、温泉井中水溶性氦气的研究相对较少,郯庐断裂带(郯城—庐江断裂带)作为一条巨型走滑断裂,分布多处含氦气的地热井、温泉,而查明地热水中氦气的来源显得尤为重要。笔者等利用在郯庐断裂带临沂段地热井、温泉内氦气的样品分析结果,分析了郯庐断裂带临沂段地热井和温泉地下水中伴生气体氦含量、分布特征,探讨了地热水中氦气来源。结果显示:在郯庐断裂带临沂段地热水中首次发现8处明显氦含量高值点,以15×10^(-6)作为氦含量的背景值,高值点明显高于背景值11.1~1360.0倍,主要分布在郯庐断裂带内及两侧;氦同位素显示氦气主要来源于地壳,少量来源于地幔,幔源氦含量最高为10.75%,这不仅为郯庐断裂带深达地幔提供了证据,而且为地下热水的热源并非直接来源于地幔而是来源于深循环地温加热或放射性生热提供了依据。因此分析认为郯庐断裂带将地壳深部、基底岩体中U、Th等放射性元素衰变产生的大量气与热带到地表,运移过程中同时生成了部分氦气,从而形成了氦气资源、地热资源富集的特征。 展开更多
关键词 氦气 地热 温泉 郯庐断裂带
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Granite is an Effective Helium Source Rock: Insights from the Helium Generation and Release Characteristics in Granites from the North Qinling Orogen, China 被引量:19
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作者 ZHANG Wen LI Yuhong +4 位作者 ZHAO Fenghua ZHOU Zheng HAN Wei ZHOU Junlin ZHANG Qiao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期114-125,共12页
Global helium(He) shortage is a challenging problem;however, the types of helium source rock and the mechanisms of He generation and release therein remain still poorly understood. In this study, in order to evaluate ... Global helium(He) shortage is a challenging problem;however, the types of helium source rock and the mechanisms of He generation and release therein remain still poorly understood. In this study, in order to evaluate the potential of granite as an effective helium source rock, we collected granitic samples from the North Qinling Orogen, Central China, in the south of the helium-rich Weihe Basin. The helium generation and release behaviors in granite were studied through analysis of U and Th concentrations, EMPA images, and He and Ar concentrations and isotopic ratios extracted by crushing and stepwise heating. The results indicate that Ar has a better retention and a lower mobility than He. 3 He/4 He ratios released by crushing and stepwise heating are 0.016–0.056 RA and 0.003–0.572 RA, respectively, where RA is the atmospheric 3 He/4 He of 1.4×10-6, reflecting a crustal and radiogenic source. Helium concentrations extracted by the two ways are 0.13–0.95 ucm3 STP/g and 7.82–115.62 ucm3 STP/g, respectively, suggesting that matrix-sited He accounts for more than 98% of total helium preserved in granite. In addition, the total generated He amounts in granites are calculated based on the measured U and Th concentrations in granitic samples. Dividing the preserved He quantities by the generated He amounts, it turned out that less than 10% of He produced since the formation of the granite is preserved in the rock over geological time, suggesting that more than 90% generated He can be transferred to the Weihe Basin. Temperature and fracture are the two critical factors controlling He release. Based on the relationship between He diffusivity of granites and temperature and the He closure temperatures of a variety of U-and Th-rich minerals(27–250°C), we estimate that He can be partially released out of granite at the depths <400 m and totally released at the depths >7800 m. Fractures provide effective transfer of free He from deep source rocks to shallow reservoirs. Finally, a model on granite as an effective helium source rock is established. We suggest exploring He resources in hydrocarbon basins with granitic basement(or adjacent to granite bodies), high geothermal field, and young active fractures. 展开更多
关键词 GRANITE helium source rock helium DIFFUSIVITY CRUSHING STEPWISE heating
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市域D型车辆气密性试验方法现状与展望
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作者 贾晓沛 杜文韬 《液压气动与密封》 2025年第1期119-121,共3页
针对市域D型车辆气密性试验标准和试验方法展开讨论,对传统车辆气密性试验方法进行总结并分析其优缺点。提出一种新的车辆气密性试验方法,并对该氦质谱气密性检测法原理及试验应用做了阐述,以及展望了市域D型车辆气密性试验的未来技术。
关键词 市域D型 气密性试验 试验标准 氦质谱检测法
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超临界氦循环泵隔热结构热设计及热沉位置的热分析
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作者 朱迎秋 张子健 +1 位作者 张启勇 成安义 《真空与低温》 2025年第1期74-79,共6页
聚变堆主机关键系统综合研究设施(Comprehensive Research Facility for Fusion Technology,CRAFT)超临界氦阀箱内的超临界氦循环泵为超导磁体提供大流量超临界氦,根据功能要求对超临界氦泵体的隔热区域进行了隔热设计。确定了氦循环泵... 聚变堆主机关键系统综合研究设施(Comprehensive Research Facility for Fusion Technology,CRAFT)超临界氦阀箱内的超临界氦循环泵为超导磁体提供大流量超临界氦,根据功能要求对超临界氦泵体的隔热区域进行了隔热设计。确定了氦循环泵的隔热结构,计算分析了热沉位置范围,对氦循环泵的漏热量进行了核算;采用仿真软件ANSYS,数值分析了氦循环泵的隔热性能和热沉位置对泵体漏热的影响,结果显示热沉位置H为0.064 m时,可保证液氦质量流量,泵体漏热达到最小值8.71 W,满足此值小于10 W的指标要求。 展开更多
关键词 CRAFT超导磁体平台 超临界氦泵 隔热结构 热沉
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Helium Isotope Geochemistry of Ultrahigh-Pressure Metamorphic Eclogites From the Dabie-Sulu Terrane in East China 被引量:13
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作者 LI Yanhe LI Jincheng +1 位作者 SONG Hebin LIU Xiaochun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第1期14-18,共5页
: The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He-4He diagram. The 3He/4He ratios of eclog... : The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He-4He diagram. The 3He/4He ratios of eclogites are obviously correlated with the types of their surrounding rocks. The helium isotope composition of the eclogites from the Bixiling complex possesses characters of mantle-derived rocks with the 3He/4He ratio being 5.6 Ra. The 4He concentration of the eclogites exhibits visible inverse correlation with the δ18O value of the quartz in the eclogites from the Sulu area. The δ18O values of the eclogites change synchronously with those of the country rocks. Those results suggest that protoliths of the eclogites were basic-ultrabasic rock bodies or veins intruding into the continental crust in the early stage; strong exchange and hybridization between the basic-ultrabasic rocks and continental rocks and the atmospheric water during the intrusion led to abrupt increase of the 3He/4He ratios, δ18O values and Nd(0) values of the intrusive bodies or veins, which show characters of continental rocks. This indicates that the eclogites are autochthonous. 展开更多
关键词 ECLOGITES helium isotope Dabie-Sulu terrane
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Degassing of primordial hydrogen and helium as the major energy source for internal terrestrial processes 被引量:12
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作者 Arie Lev Gilat Alexander Vol 《Geoscience Frontiers》 CAS 2012年第6期911-921,共11页
Examples of the mightiest energy releases by great earthquakes and volcanic eruptions and hypotheses providing explanations for them are analyzed along with the results of some recently pub- lished researches and visu... Examples of the mightiest energy releases by great earthquakes and volcanic eruptions and hypotheses providing explanations for them are analyzed along with the results of some recently pub- lished researches and visualizations. The emerging conclusions are that the mechanism of the strong earthquake is a chemical explosion; that volcanic eruption is a special type of earthquake wherein the hypocenter rises to the earth-surface; and that there is an association between the seismic-volcanic processes and mantle "fluids" and the lack of energy for mantle plumes. A conceptual system of hypoth- eses is put forward to explain the conservation of energy during Earth's accretion, its quasi-stable release by primordial H- and He-degassing and of the crucial role of the energy of degassing-eomprising- reactions in endogenic processes. Specific mechanisms and chemical processes are proposed for the gas-liquid mantle plumes melting through the solid mantle using heat-energy released in reactions of their metamorphic and chemical transformation under gradual decrease of pressure and temperature; volcanic gases are put forward as energy carriers. 3He performance as a unique measuring transformer correlative to the internal heat flow was used for calculation of energy release by degassing; it equals to 5.12 × 1020 J/yr, an amount of energy five-fold greater than the entire energy loss involved in earthquake and volcanic activity. The hypotheses proposed are objectively testable. 展开更多
关键词 EARTHQUAKES VOLCANISM Energy-source HYDROGEN helium DEGASSING
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超大型负压低温换热器的热工特性分析
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作者 任志文 黄桂朝 +3 位作者 刘具龙 王倩 汤建成 王少刚 《真空与低温》 2025年第1期98-103,共6页
基于超大型氦低温系统,建立负压节流级低温换热器仿真模型,对比分析了几种翅片型式在负压、大流量和超流氦温区工况下的热工特性。结果表明,在研究范围内,交错型和波纹型翅片具有良好的强化传热效果,但两种情况阻力特性均有所恶化,且波... 基于超大型氦低温系统,建立负压节流级低温换热器仿真模型,对比分析了几种翅片型式在负压、大流量和超流氦温区工况下的热工特性。结果表明,在研究范围内,交错型和波纹型翅片具有良好的强化传热效果,但两种情况阻力特性均有所恶化,且波纹翅片阻力特性优于交错翅片。采用综合评价指标对几种翅片进行了评价,发现波纹翅片具有更好的综合性能。对波纹翅片的结构参数进行了优化研究,可为工程应用提供一定的参考。 展开更多
关键词 负压换热器 超流氦温区 大流量 交错翅片 波纹翅片 热工特性
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Crustal Composition of China Continent Constrained from Heat Flow Data and Helium Isotope Ratio of Underground Fluid 被引量:10
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作者 WANG Yang SUN Zhiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第1期178-184,共7页
Based on conservation of energy principle and heat flow data in China continent, the upper limit of 1.3 μW/m3 heat production is obtained for continental crust in China. Furthermore, using the data of heat flow and h... Based on conservation of energy principle and heat flow data in China continent, the upper limit of 1.3 μW/m3 heat production is obtained for continental crust in China. Furthermore, using the data of heat flow and helium isotope ratio of underground fluid, the heat productions of different tectonic units in China continent are estimated in range of 0.58-1.12 μW/m3 with a median of 0.85 μW/m3. Accordingly, the contents of U, Th and K20 in China crust are in ranges of 0.83-1.76 μg/g, 3.16-6.69 μg/g, and 1.0%-2.12%, respectively. These results indicate that the abundance of radioactive elements in the crust of China continent is much higher than that of Archean crust; and this fact implies China's continental crust is much evolved in chemical composition. Meanwhile, significant lateral variation of crustal composition is also exhibited among different tectonic units in China continent. The crust of eastern China is much enriched in incompatible elements such as U, Th and K than that of western China; and the crust of orogenic belts is more enriched than that of platform regions. It can also be inferred that the crusts of eastern China and orogenic belts are much felsic than those of western China and platform regions, respectively, derived from the positive correlation between the heat production and SiO2 content of bulk crust. This deduction is consistent with the results derived from the crustal seismic velocity data in China. According to the facts of the lower seismic velocity of China than the average value of global crust, and the higher heat production of China continent compared with global crust composition models published by previous studies, it is deduced that the average composition models of global continent crust by Rudnick and Fountain (1995), Rudnick and Gao (2003), Weaver and Tarney (1984), Shaw et al. (1986), and Wedepohl (1995) overestimate the abundance of incompatible elements such as U, Th and K of continental crust. 展开更多
关键词 crustal composition of continent heat flow helium isotope ratio China continent
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Helium Retention and Desorption Behaviour of Reduced Activation Ferritic/Martenstic Steel 被引量:2
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作者 王平怀 信太佑二 +5 位作者 日野友明 山内有二 谌继明 许增裕 李雄伟 刘实 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第2期225-230,共6页
The reduced activation ferritic/martenstic steel CLF-1 prepared by the Southwestern Institute of Physics in China was irradiated by helium ions with an energy of 5 keV at room temperature using an electron cyclotron r... The reduced activation ferritic/martenstic steel CLF-1 prepared by the Southwestern Institute of Physics in China was irradiated by helium ions with an energy of 5 keV at room temperature using an electron cyclotron resonance (ECR) ion irradiation apparatus. After the irradiation, the helium retention and desorption were investigated using a technique of thermal desorption spectroscopy (TDS). The experiment was conducted with both the normal and welded samples. Blisters were observed after the helium ion irradiation, and the surface density of blisters in the welded samples was lower than that in the non-welded samples. Three desorption peaks were observed in both the non-welded and welded samples. These desorption peaks corresponded to those of blister ruptures and the helium release from the inner bubbles and the defects. The amount of helium retained in the welded samples was approximately the same as that in the non- welded samples, which was much less than other reduced activation materials, such as vanadium alloy and SiC/SiC composites. 展开更多
关键词 reduced activation material helium ion irradiation helium retention fusion reactor
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薄壁构件的氦质谱正压-真空检漏试验研究
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作者 庞嘉炜 高建强 +2 位作者 陈光奇 李杰 魏裕隆 《真空》 2025年第1期15-20,共6页
对薄壁部件的内部抽真空会引起构件的周向或径向失稳导致构件报废,这是困扰薄壁部件正压定量检漏的难题。本文提出一种对薄壁构件内部充氦气、外部抽真空的正压-真空氦质谱检漏方法。设计了用正压标准漏孔同步比对的定量检漏工装,可进... 对薄壁部件的内部抽真空会引起构件的周向或径向失稳导致构件报废,这是困扰薄壁部件正压定量检漏的难题。本文提出一种对薄壁构件内部充氦气、外部抽真空的正压-真空氦质谱检漏方法。设计了用正压标准漏孔同步比对的定量检漏工装,可进行表压-0.1~0.1 MPa范围的正压-真空氦质谱定量检漏。经过对壁厚0.4 mm的不锈钢薄壁颈管部件的工况压力-真空氦质谱检漏试验,结果表明该方法检漏速度快、效率高,检漏灵敏度符合最小可检漏率要求,能很好地应用于薄壁部件的生产线批量检漏。 展开更多
关键词 氦质谱 检漏方法 薄壁部件 正压-真空检漏 最小可检漏率
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