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我国氦气资源现状及首个特大型富氦储量的发现:和田河气田
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作者 陶小晚 李建忠 +7 位作者 赵力彬 李立武 朱文平 邢蓝田 苏法卿 单秀琴 郑红菊 张立平 《地球科学》 EI CAS CSCD 北大核心 2019年第3期1024-1041,共18页
氦气是一种重要的战略稀有资源,关系国家安全和高新技术产业发展.但我国贫氦且绝大部分依赖进口,资源安全形势十分严峻,因此开展氦气资源调查非常迫切.通过全国七大含油气盆地及其他地区氦气资源及成因系统调研,明确我国中西部含油气盆... 氦气是一种重要的战略稀有资源,关系国家安全和高新技术产业发展.但我国贫氦且绝大部分依赖进口,资源安全形势十分严峻,因此开展氦气资源调查非常迫切.通过全国七大含油气盆地及其他地区氦气资源及成因系统调研,明确我国中西部含油气盆地天然气中氦气基本为壳源放射成因,其富集受富含U、Th的酸性岩或基底的分布、背斜圈闭及断裂共同控制.东部郯庐断裂带两侧含油气盆地中氦气为壳源和幔源混合成因,其富集受断裂控制明显.地热或温泉的水溶气中,含量较高的氦气主要为壳源.优选了氦气显示良好、但存在不确定性的塔里木盆地和田河气田及周缘开展氦气资源系统勘查.通过对和田河气田及周缘11口井天然气样品精细取样、分析,首次发现和田河气田为富氦气田,氦气体积含量为0.30%~0.37%(平均0.32%),为壳源成因,折算氦气探明储量1.959 1×10~8 m~3,是我国发现的首个特大型富氦氦气田.因此建议:(1)加快建设和田河气田氦气分离、液化装置,实现气田开发整体效益最大化;(2)尽快论证建设'塔里木盆地氦气战略储备基地'的可行性,开展全国主要含油气盆地氦气资源系统调查;(3)加强氦气成藏理论研究,指导氦气资源勘探. 展开更多
关键词 氦气 和田河气田 威远气田 安岳气田 塔里木盆地 四川盆地 郯庐断裂带 地球化学
Helium Isotopic Composition of the Songduo Eclogites in the Lhasa Terrane, Tibet: Information from the Deep Mantle
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作者 Zhaoli Li Jingsui Yang +1 位作者 Tianfu Li Songyong Chen 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第3期563-570,共8页
Helium isotopic compositions are considered to be ideal tracers to identify whether mantle materials have been added to crustal rocks or fluids.In this paper,we present the helium isotopic compositions of the Songduo ... Helium isotopic compositions are considered to be ideal tracers to identify whether mantle materials have been added to crustal rocks or fluids.In this paper,we present the helium isotopic compositions of the Songduo eclogites in the Lhasa terrane,Tibet.We found that garnet and omphacite in the eclogites have different helium retention characteristics.The 4He content of most omphacite grains are about 10–20 times of that of garnet,suggesting that omphacite has a higher ability to capture 4He than garnet.Similarly,there is about 10–20 times difference in 3He content between omphacite and garnet in the same eclogite samples.The 3He/4He ratios of garnet and omphacite in these rocks range from 0.27 to 0.60 Ra(relative to the modern air 3He/4He ratio,1.4×10^-6).These ratios are within the range of both mantle-and crust-derived helium,suggesting mixed sources.The Songduo eclogites have much higher3He/4He ratios than those observed in the Dabie eclogites of eastern China.Such high ratios are typically thought to be associated with deep mantle sources.We cautiously conclude that deep mantle materials might have been involved during the formation of the Songduo eclogites. 展开更多
关键词 ECLOGITE HELIUM isotopic composition HP/UHP metamorphic belt LHASA TERRANE Qinghai-Tibet Plateau
Positron Spectroscopy of Free Volume in Poly(vinylidene fluoride) after Helium Ions Irradiation
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作者 Jin-Zhe Lyu Roman Laptev Natalya Dubrova 《高分子科学:英文版》 SCIE CAS CSCD 2019年第5期527-534,共8页
Free volume is an extremely important intrinsic defect in polymers. Structurally, free volume is the randomly distributed holes in the polymer molecular chain segments. In proton exchange membrane fuel cells, free vol... Free volume is an extremely important intrinsic defect in polymers. Structurally, free volume is the randomly distributed holes in the polymer molecular chain segments. In proton exchange membrane fuel cells, free volume is also the space needed for the directional conduction of protons. Irradiation by α particles to grafting sulfonated poly(vinylidene fluoride)(PVDF) is one of the methods to produce proton exchange membrane with good proton channel rate. Positron annihilation lifetime spectroscopy was used to study the free volume size at different absorbed dose levels from 0.13 MGy to 0.65 MGy. Measurement method of positron annihilation lifetime spectroscopy for PVDF based on 44 Ti positron source was developed. For low dose irradiation at 0.26 MGy, a decrease in free volume and practically unchanged crystallinity were observed. Further increase of absorbed dose range from 0.26 MGy to 0.39 MGy led to an increasing crystallinity with the same free volume level. For the absorbed dose from 0.39 MGy to 0.65 MGy, crystallinity was decreased but free volume remained almost constant. 展开更多
关键词 POSITRON ANNIHILATION Free volume XRD Poly(vinylidene fluoride) HELIUM ions Connection Degradation
氦原子在超短中红外脉冲和极紫外光场作用下的双电离
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作者 许亮 吴婉阳 何峰 《中国激光》 EI CAS CSCD 北大核心 2019年第5期251-257,共7页
利用数值求解含时薛定谔方程的方法研究了氦原子在超短红外激光脉冲和极紫外激光场作用下的双电离过程。在此过程中,一个电子首先被极紫外激光场电离,然后氦离子既可以被接下来的红光激光场直接隧穿电离,也可以被红外激光场驱动下的电... 利用数值求解含时薛定谔方程的方法研究了氦原子在超短红外激光脉冲和极紫外激光场作用下的双电离过程。在此过程中,一个电子首先被极紫外激光场电离,然后氦离子既可以被接下来的红光激光场直接隧穿电离,也可以被红外激光场驱动下的电子再散射而发生非次序双电离。这两种双电离通道的干涉可以产生新颖的电子关联动量谱分布。当驱动红外激光脉冲为周期量级时,再散射导致的双电离的两个电子的运动方向可以相同,也可以相反。 展开更多
关键词 超快光学 双电离 动量谱 氦原子
氙气预处理对心肌缺血再灌注损伤大鼠心肌细胞保护作用研究 预览
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作者 朱婧 郭建丽 《陕西医学杂志》 CAS 2019年第1期3-5,31共4页
目的:通过观察氙气预处理对心肌缺血再灌注损伤(MIRI)大鼠心肌梗死范围、心肌细胞凋亡指数、心肌组织酶类及氧化应激反应水平的影响,探讨氙气预处理对MIRI大鼠心肌细胞的保护作用及机制。方法:随机抽签方式将64只雄性SD大鼠均分为四组... 目的:通过观察氙气预处理对心肌缺血再灌注损伤(MIRI)大鼠心肌梗死范围、心肌细胞凋亡指数、心肌组织酶类及氧化应激反应水平的影响,探讨氙气预处理对MIRI大鼠心肌细胞的保护作用及机制。方法:随机抽签方式将64只雄性SD大鼠均分为四组。假手术组(S组)仅做穿线但不结扎;MIRI组(模型组)阻断左冠状动脉前降支,使大鼠缺血30min,恢复灌注120min;0.5MAC疝气预处理+心肌I/R组(0.5XR组)和1MAC疝气预处理+心肌I/R组(1XR组)分别采用0.5MAC氙气和1MAC氙气预处理大鼠心脏后,缺血30min,恢复灌注120min。灌注120min后,测定各组大鼠心肌梗死范围、心肌细胞凋亡指数、丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)含量及血清中血清肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、一氧化氮合酶(eNOS)活性。结果:与S组相比,模型组心肌梗死范围明显增大,心肌细胞凋亡指数显著升高,心肌组织中SOD、GSH-PX和血清eNOS活性显著下降,MDA含量显著增加,血清CK、CK-MB活性显著增强(P<0.01);与模型组比,0.5XR组和1XR组大鼠心肌梗死范围显著缩小,心肌细胞凋亡指数显著下降,心肌组织中SOD、GSH-PX和血清eNOS活性显著增强,MDA含量显著下降,血清CK、CK-MB活性显著减小(P<0.05)。但0.5XR组和1XR组大鼠上述各指标间比较差异无统计学意义(P>0.05)。结论:氙气预处理对MIRI大鼠心肌组织及细胞具有保护作用,其作用机制可能与抑制机体心肌组织氧化应激反应有关。 展开更多
关键词 心肌缺血再灌注 心肌损伤 麻醉预处理 氙气 细胞凋亡 氧化应激
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Analysis of drying and saturating natural gypsum samples for mechanical testing 预览
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作者 Mohammadhossein Sadeghiamirshahidi Stanley J.Vitton 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第2期219-227,共9页
The stability of underground abandoned gypsum mines is dependent on the gypsum pillar’s strength,and most abandoned mines are in a fully saturated condition.Moisture affects the strength of gypsum and is therefore co... The stability of underground abandoned gypsum mines is dependent on the gypsum pillar’s strength,and most abandoned mines are in a fully saturated condition.Moisture affects the strength of gypsum and is therefore commonly measured when testing rock strength.For most rocks,this is a simple task of weighing the rock’s mass before and after oven-heating at a specified temperature and duration.For natural gypsum,however,this is not a straightforward process.Heating natural gypsum can result in dehydration and transformation of gypsum to hemihydrate and anhydrite,thus changing the physical characteristics of the gypsum such as its particle density which in turn affects the moisture content and strength measurements.To prevent transformation when determining the moisture content of gypsum,the American Society for Testing Materials(ASTM)recommends lowering the drying temperature from 110℃to 60℃.To investigate the temperature at which gypsum transforms to hemihydrate,we used a helium pycnometer to measure the particle densities of gypsum,hemihydrate and anhydrite.In this research,we suggest that a higher drying temperature of 80℃can be used for drying gypsum without transforming gypsum to hemihydrate.Further,preparing saturated samples for mechanical testing,which is required in stability analyses of abandoned mines,is challenging due to the dissolution of gypsum when placed in water.To address this problem,we investigated the following methods to saturate gypsum cores taking into account the solubility of gypsum:(1)water immersion,(2)vacuum saturation,and(3)improved vacuum saturation.The research indicates that all the three methods are acceptable but they should be conducted using a saturated gypsum-water solution to minimize dissolution.Further,the research found that the improved vacuum saturation method saturated the test samples within 24 h,while duration of 30 h was required for the other two methods. 展开更多
关键词 Gypsum-hemihydrate-anhydrite transformation DEHYDRATION Rock core SATURATION Moisture content HELIUM PYCNOMETER
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Effects of helium implantation on mechanical properties of (Al0.31Cr0.20Fe0.14Ni0.35) O high entropy oxide films
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作者 杨朝明 张坤 +3 位作者 裘南 张海斌 汪渊 陈坚 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第4期286-292,共7页
It is widely accepted that helium(He) bubbles can prevent dislocations from moving and causing hardening and embrittlement of the material. However, He can affect the mechanical properties of materials in various ways... It is widely accepted that helium(He) bubbles can prevent dislocations from moving and causing hardening and embrittlement of the material. However, He can affect the mechanical properties of materials in various ways. In this work,ultrafine nanocrystal high entropy oxide(HEO) films with He implantation are prepared by using a radio frequency(RF)reactive magnetron sputtering system to investigate the effects of He bubbles located at grain boundary on the mechanical properties of the films. The mechanical properties of the HEO films are investigated systematically via nanoindentation measurements. The results indicate that the grain boundary cavities induced by He implantation can degrade the hardness,the elastic modulus, and the creep resistance of the HEO films. The mechanical properties of the HEO films are sensitive to the interaction between the He bubbles and the dominating defects. 展开更多
关键词 HELIUM ACCUMULATION grain boundaries MECHANICAL properties high-entropy OXIDES
Triple oxygen isotope constraints on the origin of ocean island basalts
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作者 Xiaobin Cao Huiming Bao +4 位作者 Caihong Gao Yun Liu Fang Huang Yongbo Peng Yining Zhang 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第3期327-334,共8页
Understanding the origin of ocean island basalts(OIB) has important bearings on Earth’s deep mantle.Although it is widely accepted that subducted oceanic crust, as a consequence of plate tectonics, contributes materi... Understanding the origin of ocean island basalts(OIB) has important bearings on Earth’s deep mantle.Although it is widely accepted that subducted oceanic crust, as a consequence of plate tectonics, contributes material to OIB’s formation, its exact fraction in OIB’s mantle source remains ambiguous largely due to uncertainties associated with existing geochemical proxies. Here we show, through theoretical calculation, that unlike many known proxies, triple oxygen isotope compositions(i.e.△^17 O) in olivine samples are not affected by crystallization and partial melting. This unique feature, therefore, allows olivine △^17 O values to identify subducted oceanic crusts in OIB’s mantle source. Furthermore, the fractions of subducted ocean sediments and hydrothermally altered oceanic crust in OIB’s mantle source can be quantified using their characteristic △^17 O values. Based on published △^17 O data, we estimated the fraction of subducted oceanic crust to be as high as 22.3% in certain OIB, but the affected region in the respective mantle plume is likely to be limited. 展开更多
关键词 TRIPLE oxygen ISOTOPE Helium ISOTOPE Ocean island BASALTS MANTLE PLUME MANTLE heterogeneity Crustal recycling
Considering for the blanket structure scheme of HCCB DEMO 预览
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作者 Zhou Zhao Zaixin Li +2 位作者 Xiaoyu Wang Xueren Wang Kaiming Feng 《力学快报:英文版》 CAS CSCD 2019年第3期188-194,共7页
For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low tempera... For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low temperature limit of neutron multiplier beryllium pebbles. Based on that, preliminary design for the typical blanket module of HCCB DEMO has been carried out and verified by thermal-hydraulic analysis and structural analysis. Furthermore, the specific relationship of maximum temperature depended on the surface heating of blanket key part first wall (FW) is also analyzed. 展开更多
关键词 HELIUM cooled ceramic BREEDER (HCCB) Demonstration fusion power plant (DEMO) BLANKET structure SCHEME Preliminary design and analysis
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石碌铁矿高深溜井堵塞原因分析及处理实践 预览
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作者 吴波 张欢 王槐鸥 《现代矿业》 CAS 2019年第7期108-110,114共4页
石碌铁矿主溜井发生堵塞事故,对生产造成重大影响。事故溜井属于高深溜井,堵塞位置高,处理难度大。为能尽快疏通溜井恢复生产,认真分析了造成高深溜井发生堵塞事故的主要原因,研究参考各矿山在处理溜井堵塞事故中的经验和方法,最后选择... 石碌铁矿主溜井发生堵塞事故,对生产造成重大影响。事故溜井属于高深溜井,堵塞位置高,处理难度大。为能尽快疏通溜井恢复生产,认真分析了造成高深溜井发生堵塞事故的主要原因,研究参考各矿山在处理溜井堵塞事故中的经验和方法,最后选择竹竿爆破和气球爆破2种方式进行处理。2个方案在不同处理条件下都进行了实施,并在最后使用氦气球携带炸药爆破成功将主溜井疏通,该溜井的成功疏通为类似高深溜井堵塞处理提供了宝贵实践经验。 展开更多
关键词 主溜井 堵塞 氦气 竹竿
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Diffusion of helium in FCT zircon
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作者 Shun YU Wen CHEN +1 位作者 Jingbo SUN Ze SHEN 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第4期719-732,共14页
To gain a better quantitative understanding of zircon(U-Th)/He ages and evaluate the applicability of zircon(U-Th)/He dating, the diffusion characteristics, He diffusion kinetics, helium partial retention zone(HePRZ),... To gain a better quantitative understanding of zircon(U-Th)/He ages and evaluate the applicability of zircon(U-Th)/He dating, the diffusion characteristics, He diffusion kinetics, helium partial retention zone(HePRZ), closure temperature, and(U-Th)/He ages were investigated using high-precision laboratory step heating experiments based on the thermally activated diffusion process. The ln(D/a^2) in Fish Canyon Tuff(FCT) zircons determined from laboratory step heating experiments was negatively correlated with reciprocal temperature, as expected for thermally activated volume diffusion. The zircon activation energies ranged from 144 to 184 kJ mol^-1 with a mean of 169±12 kJ mol^-1. The closure temperatures ranged from 144 to 216℃(a cooling rate of 10℃ Ma^-1 and an effective grain radius of 38–60 μm) with an average of 176±18℃. The calculated closure temperature increased with increasing cooling rate, yielding an average zircon He closure temperature of ~136℃ at a slow cooling rate of 0.1℃ Ma^-1, whereas the closure value was ~199℃ at a cooling rate of 100℃ Ma^-1. The closure temperature increased with the equivalent spherical radius assuming a constant cooling rate. The He ages from FCT zircons were negligibly affected by grain size because of the rapid cooling. He preserved in the zircon was sensitive to temperature and holding time, and the temperature range for zircon HePRZ gradually decreased with increasing holding time. The(U-Th)/He ages from 26 FCT zircons yielded an algorithmic mean of 28.3±0.3 Ma(S.E.) and a geometric mean of 28.4±0.3 Ma(S.E.), consistent with the ages of 28.4±1.9 Ma reported by other laboratories. The FCT zircons were characterized by rapid cooling, young(U-Th)/He ages with good reproducibility, and low alpha doses. Weak correlations between the He ages and effective uranium(eU) concentrations from the FCT zircons indicated radiation damage did not significantly affect He diffusivity. 展开更多
关键词 ZIRCON HELIUM DIFFUSION (U-Th)/He CLOSURE TEMPERATURE THERMOCHRONOMETRY
Effect of ordered helium bubbles on deformation and fracture behavior of α-Zr
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作者 Si-Mian Liu Shi-Hao Li Wei-Zhong Han 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第7期1466-1472,共7页
Radiation-induced helium bubbles are detrimental to the mechanical properties of metals, usually causing severe hardening and embrittlement. Hexagonal close-packed(HCP) α-Zr alloys are one of the primary structural m... Radiation-induced helium bubbles are detrimental to the mechanical properties of metals, usually causing severe hardening and embrittlement. Hexagonal close-packed(HCP) α-Zr alloys are one of the primary structural materials for nuclear applications, however, the effect of helium bubbles on their deformation and fracture behaviors still remains unexplored. Here, we found that ordered helium bubbles prefer to align along the basal plane in HCP α-Zr. Micro-scale in situ tensile tests revealed that helium bubbles less than 8 nm in size can increase the critical resolved shear stress of the prismatic slip. However, once the helium bubbles are larger than 8 nm, a bubble-softening effect happens due to a decrease in number density of helium bubbles and an increase in porosity. Once the Schmid factor of basal slip is considerably higher than prismatic slip, bubble coalescence along the basal plane becomes the major failure mode in helium-irradiated α-Zr. 展开更多
关键词 α-Zr HELIUM BUBBLES Prismatic SLIP COALESCENCE Fracture
O2、CO2、N2对常压He多电流脉冲放电特性的影响 预览
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作者 钱丹娜 张燕 孙岩洲 《真空与低温》 2019年第1期29-35,共7页
为了研究少量的O2、CO2和N2对常压He多电流脉冲放电的影响,分别对其放电时的电流电压波形、Lissa-jious图形和发射光谱进行了实验研究。结果表明:在外加电压不变的情况下,随着分别混入的O2、CO2和N2流量的增加,每半个周期中电流脉冲的... 为了研究少量的O2、CO2和N2对常压He多电流脉冲放电的影响,分别对其放电时的电流电压波形、Lissa-jious图形和发射光谱进行了实验研究。结果表明:在外加电压不变的情况下,随着分别混入的O2、CO2和N2流量的增加,每半个周期中电流脉冲的个数并没有改变,电流脉冲的峰宽却明显变窄,从μs量级变为ns量级,此时Lis-sajous图形显示辉光放电时第一个电流脉冲所需要的外加电压要比丝状放电时低的多,介质板上的积累电荷明显减少,放电逐渐从辉光放电过渡到丝状放电,其发射光谱表明,这主要是由于放电空间内的亚稳态He(2^3S)原子逐渐减少导致的。 展开更多
关键词 常压多电流脉冲放电 辉光放电 丝状放电 发射光谱 氦气
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CAEP FEL-THz 2K低温系统氦气循环利用研究
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作者 杨林德 王汉斌 +3 位作者 单李军 沈旭明 傅剑 丁先庚 《低温与超导》 CAS 北大核心 2019年第3期8-11,共4页
中国工程物理研究院(CAEP)2K低温系统中,要对低纯度氦气进行回收和除杂。基于高压低温冷凝和吸附的方法,建成了一套氦气回收与纯化循环利用装置,单次回收低纯度氦气量为20Nm^3,低纯度氦气储存能力为1000Nm^3,纯化能力为20Nm^3/h,高纯氦... 中国工程物理研究院(CAEP)2K低温系统中,要对低纯度氦气进行回收和除杂。基于高压低温冷凝和吸附的方法,建成了一套氦气回收与纯化循环利用装置,单次回收低纯度氦气量为20Nm^3,低纯度氦气储存能力为1000Nm^3,纯化能力为20Nm^3/h,高纯氦气储存能力为3000Nm^3,能将粗氦气纯度从98%提升至优于99.9995%。实际运行表明,处理后的氦气纯度满足低温系统要求,较好地实现了氦气循环再利用,降低了系统对外部氦源补充的依赖。 展开更多
关键词 低温系统 氦气 循环利用 回收 纯化
多级氦气压气机设计开发 预览
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作者 廖健鑫 孙奇 +3 位作者 王文武 田瑞青 李冠 张粉 《东方汽轮机》 2019年第1期5-9,共5页
多级氦气压气机是第四代核电钍基熔盐堆岛外闭式循环的重要设备,工质为氦气。由于氦气渗透性较强因此该机组的密封要求较严格。同时由于该机组转速高,转速范围大,设计难度较大。最终通过设计特殊的支撑结构、特殊的转向导叶结构、特殊... 多级氦气压气机是第四代核电钍基熔盐堆岛外闭式循环的重要设备,工质为氦气。由于氦气渗透性较强因此该机组的密封要求较严格。同时由于该机组转速高,转速范围大,设计难度较大。最终通过设计特殊的支撑结构、特殊的转向导叶结构、特殊的排气蜗壳结构、干气密封和梳齿密封的配合使用等方式,来实现机组的结构及功能要求。 展开更多
关键词 氦气 轴流压气机 结构设计 第四代核电 转向导叶 密封
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Effects of Helium Implantation and Subsequent Electron Irradiation on Microstructures of Fe-11 wt.% Cr Model Alloy
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作者 李炳生 王志光 +5 位作者 申铁龙 魏孔芳 盛彦斌 柴山环树 卢喜瑞 熊安利 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第4期71-74,共4页
Helium effects on dislocation and cavity formation of Fe-11 wt.% Cr model alloy are investigated. Single-beam(electron) and dual-beam(He~+/e~-) irradiations are performed at 350℃ and 400℃ using an ultra-high voltage... Helium effects on dislocation and cavity formation of Fe-11 wt.% Cr model alloy are investigated. Single-beam(electron) and dual-beam(He~+/e~-) irradiations are performed at 350℃ and 400℃ using an ultra-high voltage electron microscope combined with ion accelerators. In-situ observation shows that the growth rate of dislocation loops is reduced in the helium pre-injected specimen. The mean size of cavities decreased in the helium preinjected specimen. The possible mechanisms are discussed. 展开更多
关键词 HELIUM MICROSTRUCTURES Subsequent
基于AspenAdsorption的氦气/甲烷吸附分离过程模拟优化 预览
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作者 肖永厚 肖红岩 +3 位作者 李本源 秦剑亮 邱爽 贺高红 《化工学报》 EI CAS CSCD 北大核心 2019年第7期2556-2563,共8页
工业氦气主要通过深冷、膜分离和变压吸附(PSA)耦合从天然气提取,其中PSA是获得高纯He的关键。吸附过程模拟可以克服实验局限,有效指导工程设计、优化工艺条件。以体积分数90%的粗He为原料,利用AspenAdsorption软件建立He/CH4单塔PSA模... 工业氦气主要通过深冷、膜分离和变压吸附(PSA)耦合从天然气提取,其中PSA是获得高纯He的关键。吸附过程模拟可以克服实验局限,有效指导工程设计、优化工艺条件。以体积分数90%的粗He为原料,利用AspenAdsorption软件建立He/CH4单塔PSA模型,获得穿透曲线。以此为基础,建立双塔分离流程,分析吸附、顺放、逆放、冲洗、升压步骤中吸附塔内气相组成的变化,五步最佳操作时间分别为60、180、30、60和180s。在三塔流程中,一个循环周期的最佳吸附时间和均压时间分别为135s和90s,产品纯度可达98.42%,回收率达60.45%。在五塔流程中,考虑到各步骤时间的匹配及生产的连续性,需要对一个周期内的循环时间进行优化。循环时间为300~340s时,产品纯度达到99.07%以上。 展开更多
关键词 吸附 氦气 过程模拟 优化
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铂探测器在重水堆核电站二号停堆系统中的应用与维护 预览
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作者 张振超 徐清华 刘铮 《仪器仪表用户》 2019年第3期52-54,共3页
本文介绍了铂探测器的结构和工作原理,探测器组件的结构,二号停堆系统铂探测器测量回路的工作原理,并结合调试及运行期间所积累的经验,对铂探测器的阻抗、电容和氦气环境的测量方法,故障诊断以及铂探测器的更换方法进行介绍和分析。希... 本文介绍了铂探测器的结构和工作原理,探测器组件的结构,二号停堆系统铂探测器测量回路的工作原理,并结合调试及运行期间所积累的经验,对铂探测器的阻抗、电容和氦气环境的测量方法,故障诊断以及铂探测器的更换方法进行介绍和分析。希望通过此文章能对类似的检修工作提供有意义的参考。 展开更多
关键词 铂探测器 探测器组件 阻抗 电容 氦气
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渭河盆地氦气成藏条件分析及资源量预测
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作者 张文 李玉宏 +3 位作者 王利 赵峰华 韩伟 宋昌贵 《天然气地球科学》 CSCD 北大核心 2018年第2期236-244,共9页
渭河盆地氦气资源量在计算原理和参数选取上存在较大争议。据此,统计了渭河盆地101件油气井和地热井样品的气体成分和氦同位素数据,分析了该盆地的氦气成藏条件,并在综合选取和评估各项参数的基础上,估算了渭河盆地氦气资源量。结果表明... 渭河盆地氦气资源量在计算原理和参数选取上存在较大争议。据此,统计了渭河盆地101件油气井和地热井样品的气体成分和氦同位素数据,分析了该盆地的氦气成藏条件,并在综合选取和评估各项参数的基础上,估算了渭河盆地氦气资源量。结果表明,钻孔样品氦气体积分数平均为1.50%,最高达9.23%;氦源岩、地下水系统、载体气和断裂是氦气生成、运移和成藏的控制条件,其中盆地南缘花岗岩体和盆地内部隐伏磁性体是盆地最主要的氦源岩;根据盆地内地热流体储量、气水比、氦气体积分数估算出盆地内氦气资源量为21.30×10^8m^3;根据氦源岩有效面积、水循环深度、岩体密度、铀钍含量估算得出自花岗岩体形成、盆地断陷和储层形成后的生氦量分别为185.21×10^8m^3、37.58×10^8m^3和4.16×10^8m^3。综合认为渭河盆地的氦气资源勘探前景良好。 展开更多
关键词 渭河盆地 氦气 成藏条件 资源量
低温氦气透平膨胀机导向叶栅的数值模拟
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作者 李晓明 李健 李青 《低温与超导》 北大核心 2018年第4期1-5,共5页
低温氦气透平膨胀机是大型低温氦制冷系统的关键部件,其导向叶栅对整个透平膨胀机的效率有着重要影响。采用计算流体动力学(CFD)软件CFX,运用标准k-ε流模型,以低温氦气为工质,对所设计的透平膨胀机导向叶栅进行了全流道数值模拟... 低温氦气透平膨胀机是大型低温氦制冷系统的关键部件,其导向叶栅对整个透平膨胀机的效率有着重要影响。采用计算流体动力学(CFD)软件CFX,运用标准k-ε流模型,以低温氦气为工质,对所设计的透平膨胀机导向叶栅进行了全流道数值模拟。导向叶栅采用TC系列叶型。对不同叶型,不同叶片数下导向叶栅进行数值模拟。经过计算,得到了TC-2P、TC-3P、TC-4P三种叶型在设计工况下的结果,发现采用TC-2P叶型时,导向叶栅具有较好的性能,同时得到了导向叶栅性能随着叶片数的变化规律。 展开更多
关键词 透平膨胀机 导向叶栅 低温系统 氦气 数值计算
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