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All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules
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作者 C.S.Gomes F.E.Jorge A.Canal Neto 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期238-246,共9页
A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA Hamiltonian.This set was augmented with diffuse functions ... A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA Hamiltonian.This set was augmented with diffuse functions to describe electrons farther away from the nuclei adequately.Using the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were calculated.The addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular properties.For atomization energies,a similar observation emerges when considering spin-orbit couplings.With the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental values.Performance evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied. 展开更多
关键词 QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties
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CANDU堆通过冷却剂133Xe浓度趋势查找破损燃料 被引量:3
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作者 胡威 《核科学与工程》 CAS CSCD 北大核心 2020年第2期349-352,共4页
秦山第三核电厂两台CANDU6反应堆通过测量缓发中子查找破损燃料的成功率很低,本文通过在线监测的冷却剂133 Xe浓度变化趋势分析方法查找破损燃料,判断破损燃料棒束的入堆时间,确定破损燃料棒束所在冷却剂环路。通过换料前后的133 Xe浓... 秦山第三核电厂两台CANDU6反应堆通过测量缓发中子查找破损燃料的成功率很低,本文通过在线监测的冷却剂133 Xe浓度变化趋势分析方法查找破损燃料,判断破损燃料棒束的入堆时间,确定破损燃料棒束所在冷却剂环路。通过换料前后的133 Xe浓度趋势,可以确定换料通道内是否存在破损棒束,以及破损燃料棒束是否卸出堆芯。该方法在实际应用中取得了良好的效果,近年来成功定位了5个破损燃料通道。 展开更多
关键词 CandU-6重水堆 破损燃料查找 133Xe浓度趋势 冷却剂 换料
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Kr and Xe isotopic compositions of Fe-Mn crusts from the western and central Pacific Ocean and implications for their genesis 被引量:2
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作者 BU Wenrui SHI Xuefa +3 位作者 LI Li ZHANG Mingjie G.P.Glasby LIU Jihua 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第8期26-33,共8页
Kr and Xe nuclide abundance and isotopic ratios of the uppermost layer of Fe-Mn Crusts from the western and central Pacific Ocean have been determined. The results indicate that the Kr and Xe isotopic composi-tions, l... Kr and Xe nuclide abundance and isotopic ratios of the uppermost layer of Fe-Mn Crusts from the western and central Pacific Ocean have been determined. The results indicate that the Kr and Xe isotopic composi-tions, like that of He, Ne and Ar, can be classified into two types: low3He/4He type and high3He/4He type. The low3He/4He type crusts have low84Kr and132Xe abundance, while the high3He/4He type crusts have high84Kr and132Xe abundance. The82Kr/84Kr ratios of the low3He/4He type crusts are lower than that of the air, while the83Kr/84Kr and86Kr/84Kr ratios are higher than those of the air. The Kr isotopic ratios of the high-er3He/4He type crusts are quite similar to those of the air. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the low3He/4He type sample are distinctly lower than those of the air, whereas the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are higher than those of the air. The low3He/4He type samples have the diagnostic characteristics of the MORB, with excess129, 131, 132, 134, 136Xe relative to130Xe compared with the solar wind. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the high3He/4He type samples are slightly higher than those of the air, and the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are qiute similar to those of the air. The noble gases in the Fe-Mn crusts are derived from the lower mantle, and they are a mixture of lower mantle primitive component, radiogenic component and subduction recycled component. The helium isotopic ra-tios of the low mantle reservoir are predominantly controlled by primitive He (3He) and U and Th radiogenic decayed He (4He), but the isotopic ratios of the heavier noble gases, such as Ar, Kr and Xe, are controlled to different extent by recycling of subduction components. The difference of the noble isotopic compositions of the two type crusts is the result of the difference of the noble isotopic composition of the mantle source reservoir underneath the seamounts the crusts occurred, the noble gases of the high3He/4He type crusts are derived mainly from EM-type lower mantle reservoir, and the noble gases in the low3He/4He type crusts are derived mainly from HIMU-type lower mantle reservoir. 展开更多
关键词 Fe-Mn crusts Kr and Xe isotopes mantle reservoir Pacific Ocean subduction recycling
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Comparison of Xe single bubble sonoluminescence in water and sulfuric acid 被引量:1
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作者 安宇 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2984-2988,共5页
Using the equations of fluid mechanics with proper boundary conditions and taking account of the gas properties, we can numerically simulate the process of single bubble sonoluminescence, in which electron-neutral ato... Using the equations of fluid mechanics with proper boundary conditions and taking account of the gas properties, we can numerically simulate the process of single bubble sonoluminescence, in which electron-neutral atom bremsstrahlung, electron-ion bremsstrahlung and recombination radiation, and the radiative attachment of electrons to atoms and molecules contribute to the light emission. The calculation can quantitatively or qualitatively interpret the experimental results. We find that the accumulated heat energy inside the compressed gas bubble is mostly consumed by the chemical reaction, therefore, the maximum degree of ionization inside Xe bubble in water is much lower than that in sulfuric acid, of which the vapour pressure is very low. In addition, in sulfuric acid much larger pa and R0 are allowed which makes the bubbles in it much brighter than that in water. 展开更多
关键词 SONOLUMINESCENCE IONIZATION Xe bubble
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Progresses of hyperpolarized ^(129)Xe NMR application in porous materials and catalysis 被引量:3
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作者 Benhan Fan Shutao Xu +1 位作者 Yingxu Wei Zhongmin Liu 《Magnetic Resonance Letters》 2021年第1期11-27,共17页
^(129)Xe NMR has been proven to be a powerful tool to investigate the structure of porousmaterials. Xenon is a monatomic noble gas which could be used as a probe due to theextremely sensitive to its local environment.... ^(129)Xe NMR has been proven to be a powerful tool to investigate the structure of porousmaterials. Xenon is a monatomic noble gas which could be used as a probe due to theextremely sensitive to its local environment. Optical pumping techniques for production ofhyperpolarized (HP) xenon have led to an increase of sensitivity up to orders of magnitudecompared with traditional ^(129)Xe NMR. This review summarizes the application of thistechnique in porous materials and heterogeneous catalysis in recent ten years, involving ofzeolites, metal-organic frameworks (MOFs), catalytic process and kinetics. 展开更多
关键词 Solid-state NMR Hyperpolarized^(129)Xe REVIEW Porous materials CATALYSIS
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Field Observations of the Vulnerable Impressed Tortoise, Manouria impressa, from Southern Laos and Notes on Local Chelonian Trade
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作者 Thomas CALAME Thomas N. E. GRAY +2 位作者 Martha HURLEY Robert J. TIMMINS Khamhou THONGSAMOUTH 《Asian Herpetological Research》 SCIE 2013年第2期151-154,共4页
Observations of wild chelonians in Indochina are uncommon with most records and specimens coming from the commercial wildlife trade. During the surveys of the Xe Sap National Protected Area in southern Laos between Fe... Observations of wild chelonians in Indochina are uncommon with most records and specimens coming from the commercial wildlife trade. During the surveys of the Xe Sap National Protected Area in southern Laos between February and May 2012, four impressed tortoises, Manouria impressa (IUCN Red List: Vulnerable) were found in three separate field locations. There are few published observations of this species in the wild. We also present data on threats and local value of chelonians in the wildlife trade. 展开更多
关键词 Xe Sap National Protected Area Laos Manouria impressa wildlife trade
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基于Android操作系统的电力变压器比率差动保护比率系数检验的软件设计 被引量:2
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作者 徐皇清 谢海发 《电力学报》 2016年第3期236-240,共5页
随着Android操作系统普及和对应的硬件大力发展,对人们的移动办公产生了深远的影响。基于传统的PC机完成的工作被现在可以基于Android平台的移动终端所代替,所以为人们平时工作设计基于Android平台的软件意义十分重大。先介绍了电力变... 随着Android操作系统普及和对应的硬件大力发展,对人们的移动办公产生了深远的影响。基于传统的PC机完成的工作被现在可以基于Android平台的移动终端所代替,所以为人们平时工作设计基于Android平台的软件意义十分重大。先介绍了电力变压器比率差动保护的计算方法,结合现场的工作实际,对于比率差动保护的比率系数计算提出两点法来计算,设计计算的算法,然后根据算法,基于Delphi XE7平台设计了能运行的Android操作系统的.apk安装文件,安装在手机和平板电脑上,并且进行了验证,得到满意的结果,设计的这款软件已经在揭阳供电局推广应用。 展开更多
关键词 andriod操作系统 比率差动保护 比率系数 DELPHI XE7平台
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Energy-Transfer Processes of Xe(6p[1/2]0,6p[3/2]2,and 6p[5/2]2) Atoms under the Condition of Ultrahigh Pumped Power
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作者 Shan He Jun-zhi Chu +9 位作者 Dong Liu Xue-yang Li Jing-wei Guo Jin-bo Liu Shu Hu Hui Li Peng-yuan Wang Ying Chen Feng-ting Sang Yu-qi Jin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第6期741-748,733,共9页
The kinetic processes of Xe(6p[1/2]0, 6p[3/2]2, and 6p[5/2]2) atoms under the focused condition were investigated. The atomic density of the laser prepared state significantly increases. Therefore, the probability of ... The kinetic processes of Xe(6p[1/2]0, 6p[3/2]2, and 6p[5/2]2) atoms under the focused condition were investigated. The atomic density of the laser prepared state significantly increases. Therefore, the probability of the energy-pooling between two high-lying atoms increases. There are three major types of the energy-pooling collisions. The first type is the energy-pooling ionization. Once the excitation laser is focused, the obvious ionization can be observed from the side window whenever the laser prepared state is 6p[1/2]0, 6p[3/2]2, or 6p[5/2]2 state. Ionization of Xe is attributed to the energy-pooling ionization or a Xe* atom reabsorbing another excitation photon. The second type is energy-pooling with big energy difference. When the 6p[1/2]0 state is the laser prepared state, the energy-pooling collision between two 6p[1/2]0 atoms can produce one 5d[3/2]1 atom and one 6s'[1/2]0 atom. The third type is energy-pooling with small energy difference. The intensities of fluorescence lines are much stronger that five secondary 6p states act as the upper states, and the rising edges of these fluorescence lines are much steeper. The primary mechanism of generating the secondary 6p atoms is energy-pooling collision instead of collision relaxation. Based on the collision probability, the rate of energy-pooling between two 6p[1/2]0 atoms is deduced (6.39x10^8s-1). In addition, the 6s atoms also increase under the focused condition. Therefore, all the fluorescence lines are serious trailing by radiation trapping. 展开更多
关键词 Energy-pooling KINETICS XE Ultrahigh pumped power
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A NEW EXX SYSTEM AND ITS APPLICATIONS
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作者 邬显慷 曾宪周 +1 位作者 孙永年 杨福家 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期76-81,共6页
IXX (or PIXE-induced XRF) technique gains two main advantages over conventional PIXE method. First, it can be used to avoid or significantly reduce background and spectral interferences from major elements in the samp... IXX (or PIXE-induced XRF) technique gains two main advantages over conventional PIXE method. First, it can be used to avoid or significantly reduce background and spectral interferences from major elements in the sample by proper selecting the primary target. Second, target damage is greatly reduced, so that it is more suitable for the analysis of heatsensitive and delicate specimens. A new IXX system with a very tight geometry is described. Some of its performances and preliminary applications are presented. 展开更多
关键词 P1XE XRF IXX MATRIX effect TARGET DAMAGE
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HIGH ENERGY Xe^+ ENHANCED ADHESION OF Al AND Ag FILMS ON OPTICAL GLASS
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作者 张通和 刘伊犁 +1 位作者 孙寅官 尚世铉 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第4期236-239,共4页
The samples consisting of 100nm Al or Ag film on optical glass substrate were irradiated by a beam of Xe 5×10<sup>15</sup> to 2×10<sup>16</sup> cm<sup>-2</sup> with energy... The samples consisting of 100nm Al or Ag film on optical glass substrate were irradiated by a beam of Xe 5×10<sup>15</sup> to 2×10<sup>16</sup> cm<sup>-2</sup> with energy 320 keV. The adhesion of films on substrates was tested by Xe<sup>+</sup> irradiation. Optical character was measured by spectrophotometer. The ion mixing amount was measured by RBS. The results showed that after ion irradiating the adhesion of the film on the glass is enhanced. The adherent strength is greater than 10 kg/cm<sup>2</sup>. The thermal stability of the films is good. The irradiated film is more optically efficient, the surface is smooth and rendered more corrosion resistance. The mechanism of the film adhesion was discussed. 展开更多
关键词 High energy Xe^+ Bombard AL and Ag FILMS Ion beam ENHANCED ADHESION
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Alternating Parity Band in Octupole-Soft ^(140)Xe with Axial Vibrational-Rotational Model and Triaxial Rigid Rotor Model
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作者 Xiao Lu Bin Qi Shou-Yu Wang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第10期9-13,共5页
Energies of the yrast positive-and negative-parity excited states in140 Xe are reproduced by two different models considering quadrupole-octupole deformations, namely the axial vibrational-rotational model and the tri... Energies of the yrast positive-and negative-parity excited states in140 Xe are reproduced by two different models considering quadrupole-octupole deformations, namely the axial vibrational-rotational model and the triaxial rigid rotor model, and compared with the stable octupole-deformed222 Th. The origin of the energy difference between the opposite parity sequences is considered from two different mechanisms, the vibration in axial deformed energy minima and the rotation considering the effective triaxial deformation. The success of reproducing the data in both the models implies that these two mechanisms are equivalent on some level for the octupole-soft nuclei. By investigating the probability distributions for projection of total angular momentum in the triaxial rigid rotor model, it is found that such an energy difference is associated with the difference of orientation of the rotational axis. 展开更多
关键词 Alternating Parity Band in Octupole-Soft Xe with Axial Vibrational-Rotational Model and Triaxial Rigid Rotor Model
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鉴赏级音响系统———“XES”
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作者 小汤 《轿车情报》 1999年第2期36-37,共2页
关键词 汽车 音响 索尼 xes
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Light-Induced Mid-Infrared Emission of Liquid Carbon Tetrachloride and Benzene
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作者 Sofya Terpugova Olga Degtyareva +1 位作者 Valery Savransky Evgeni Terpugov 《American Journal of Analytical Chemistry》 2015年第9期731-745,共15页
Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spect... Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spectrometer is more advantageous for studying any samples, including biological samples without any damage. This technique permits obtaining unique information on the molecule structure via vibrational excitation fundamental frequencies, overtones, and combination modes. It also enables a direct observation of vibrational radiation transitions in vibrationally excited molecules as well as the channels of vibration energy redistribution, which is not allowed with any other method. In this work, the LIRES is being tested as a technique for studying of vibrationally-excited molecules of carbon tetrachloride and benzene in the liquid phase. On the other hand, using transparent liquids, we had tried to understand some of the physical phenomena that can drive emission in mid-IR. The characteristics of the infrared emission of both liquid species produced by different wavelength radiation from various types of light systems (100 - watt Xe-lamp and Nd:YAG laser;lambda = 1064 nm (8 mW) and lambda = 532 nm (4 mW)) are presented. We demonstrated that the IR-signal, as well as spectral properties of carbon tetrachloride and benzene, was dependent on the wavelength and power of excitation beam. Results obtained with different light sources show that the visible light produces a nonlinear IR-emission signal in transparent liquids. We believe that the visible light is the source of the nonlinear response and is producing the vibration excitation as well as photostimulated transformations of the molecules possessing the high activity for the nonlinear response. 展开更多
关键词 FT-IR EMISSION Spectroscopy LIGHT-INDUCED MID-INFRARED EMISSION Carbon TETRACHLORIDE BENZENE Xe-Lamp Nd:YAG Laser
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X and γ-rays emission probabilities of ^(131)I and ^(133)Xe
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作者 Pasa Yalcin Arif Bastug 《Natural Science》 2011年第7期617-621,共5页
Radioactive nuclides as 131I and 133Xe are increasingly used for both clinical diagnosis and therapeutic treatment of the patient. For example, 131I is used for the treatment of thyroid gland cancer. Otherwise, 133Xe ... Radioactive nuclides as 131I and 133Xe are increasingly used for both clinical diagnosis and therapeutic treatment of the patient. For example, 131I is used for the treatment of thyroid gland cancer. Otherwise, 133Xe is used in ventilation studies to assess and evaluate pulmonary function and to provide images of the lungs in both cardiac and pulmonary diseases, such as asthma, pulmonary emphysema, bronchiectasis, carcinoma of the lung, and pulmonary embolism [1,2]. Furthermore, cerebral blood flow is measured using 133Xe inhalation. In this study, the X and γ-rays emission probabilities in the decay of 131I and 133Xe were precisely measured with a calibrated Si(Li) detector. Results of this study were compared using available results in the literature. Good agreement was observed between our results and available results in the literature. 展开更多
关键词 ^(131)I ^(133)Xe X-rays Emission Probabilities γ-rays Emission Probabilities
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裂变谱中子诱发^(235)U裂变产物核Xe的产额评价
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作者 曹超维 李畅 +4 位作者 舒能川 刘玲 宿阳 陈永静 刘丽乐 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第11期2269-2277,共9页
裂变产额是核工程应用和核物理科研中最重要的基础核数据之一,特别是裂变气体产物核,对核装置的设计、运行有不可忽视的影响,因此对中子诱发裂变的气体产物核裂变产额进行评价,得到可靠的产额对核工程的应用和基础研究核技术的发展具有... 裂变产额是核工程应用和核物理科研中最重要的基础核数据之一,特别是裂变气体产物核,对核装置的设计、运行有不可忽视的影响,因此对中子诱发裂变的气体产物核裂变产额进行评价,得到可靠的产额对核工程的应用和基础研究核技术的发展具有重要意义。本工作针对裂变谱能区中子诱发^(235)U裂变的Xe气体产物核,在EXFOR实验数据基础上,采用基于Zp模型的裂变统一评价方法,对其所在质量链的裂变产物的独立产额、累积产额进行了统一拟合评价,并与现有评价库中Xe的产额进行了比较,对存在分歧的产额进行了进一步分析,给出了合理的解释。与传统方法比较,统一评价方法给出的产额具有更好的可靠性和合理性,同时解决了传统方法独立产额、累积产额不自洽的问题。 展开更多
关键词 裂变产额 Zp模型 ^(235)U中子诱发裂变 XE
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静态法和动态法评价活性炭分离低浓度Xe和Kr的性能
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作者 陈彬 陈莉云 +4 位作者 伍岳 曹天 张文祥 武山 马和平 《核化学与放射化学》 CAS CSCD 北大核心 2024年第3期231-239,I0002,共10页
为获得高比活度的Xe测量源,开展了常温常压下CF-1450活性炭分离低浓度Xe和Kr的研究。利用液氮温度下N2的吸附脱附测试对CF-1450活性炭的孔结构进行了表征。结果表明,CF-1450活性炭的BET比表面积为1680 m^(2)/g,孔径分布以微孔为主。采... 为获得高比活度的Xe测量源,开展了常温常压下CF-1450活性炭分离低浓度Xe和Kr的研究。利用液氮温度下N2的吸附脱附测试对CF-1450活性炭的孔结构进行了表征。结果表明,CF-1450活性炭的BET比表面积为1680 m^(2)/g,孔径分布以微孔为主。采用静态吸附法和混合气体动态吸附-脱附法研究了CF-1450活性炭常温常压下分离低浓度Xe和Kr的性能。在25℃时,CF-1450活性炭的Xe静态吸附容量为3.25 mmol/g,Kr静态吸附容量为1.30 mmol/g;Xe亨利系数为0.21 mmol/(g·kPa),Kr亨利系数为0.02 mmol/(g·kPa),Xe/Kr亨利选择性为10.5。在低压下,利用IAST法计算的Xe/Kr吸附选择性(y(Xe)∶y(Kr)=50∶50,y为混合气体中Xe、Kr的摩尔分数)为10.6。CF-1450活性炭对Xe和Kr的零点等量吸附热分别为35.7 kJ/mol和13.9 kJ/mol。基于CF-1450活性炭动态吸附分离和动态脱附分离低浓度Xe和Kr的研究结果,建立了常温常压下动态吸附-脱附法分离低浓度Xe和Kr的工艺流程,Xe回收率为79%,Kr去污因子为195。 展开更多
关键词 活性炭 低浓度气体 XE KR 吸附 分离
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超极化^(129)Xe MR用于COPD急性加重的肺功能研究
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作者 李连杰 郑瑜 +10 位作者 谢树光 张鸣 李红闯 刘小玲 赵修超 韩叶清 李海东 范丽 萧毅 刘士远 周欣 《波谱学杂志》 CAS 2024年第4期363-372,共10页
慢性阻塞性肺疾病(COPD)急性加重(AECOPD)是COPD自然病程中的重要不良事件,本研究利用超极化^(129)Xe MR技术探究了AECOPD疾病模型的肺泡微结构和气血交换功能变化.结果表明,相比于肺气肿组,急性加重组的肺部微结构变化不大,但气血交换... 慢性阻塞性肺疾病(COPD)急性加重(AECOPD)是COPD自然病程中的重要不良事件,本研究利用超极化^(129)Xe MR技术探究了AECOPD疾病模型的肺泡微结构和气血交换功能变化.结果表明,相比于肺气肿组,急性加重组的肺部微结构变化不大,但气血交换功能显著下降.这些测量结果与组织学以及肺功能检查结果具有较好的相关性,证明了超极化^(129)Xe MR对AECOPD检测的可行性与灵敏性. 展开更多
关键词 超极化^(129)Xe MR 扩散加权成像 化学位移饱和恢复 COPD 肺气肿 急性加重
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2.79μm高速转镜调Q Er,Cr:YSGG纳秒窄脉冲激光器
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作者 朱永斌 马圣洁 +3 位作者 程庭清 王礼 陈月明 江海河 《光学精密工程》 EI CAS CSCD 北大核心 2024年第8期1122-1129,共8页
转镜调Q无插入损耗,是获得窄脉冲、高峰值功率输出激光的直接方式。纳秒脉冲需要使用高速转镜调Q,并精准控制电机转速与氙灯放电延时,以使激光介质上能级粒子数反转最大,获得最大激光能量输出。本文设计了以Arduino mega 2560单片机为... 转镜调Q无插入损耗,是获得窄脉冲、高峰值功率输出激光的直接方式。纳秒脉冲需要使用高速转镜调Q,并精准控制电机转速与氙灯放电延时,以使激光介质上能级粒子数反转最大,获得最大激光能量输出。本文设计了以Arduino mega 2560单片机为核心的高速转镜调Q控制系统,通过精确单片机解析串口屏指令控制激光电源的充放电和高速电机启停,同时通过对转镜脉冲信号整合降频控制氙灯放电时刻,实现对延迟时间的精准控制,实现了灯泵Er,Cr:YSGG激光纳秒窄脉冲调Q输出。在5 Hz重复频率下,转镜转速为650 r/s时,获得的最高单脉冲激光能量为45.7 mJ、脉冲宽度为86.2 ns,相应的峰值功率为530.2 kW。 展开更多
关键词 转镜调Q 固体激光器 ER Cr:YSGG激光 ARDUINO 氙灯泵浦
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基于Rb-Xe体系核磁共振陀螺仪的Xe极化场测量方法
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作者 王柯穆 孙兵锋 +3 位作者 熊志强 邓敏 汪之国 罗晖 《飞控与探测》 2024年第2期88-93,共6页
核磁共振陀螺仪具有小体积、高精度、低功耗等优点,是未来高精度微小型陀螺的主要发展方向之一。原子气室内Xe核自旋的极化是衡量原子气室性能的一个重要参数,直接影响陀螺的角随机游走,因此准确快速地测量极化场有利于研制性能更优的... 核磁共振陀螺仪具有小体积、高精度、低功耗等优点,是未来高精度微小型陀螺的主要发展方向之一。原子气室内Xe核自旋的极化是衡量原子气室性能的一个重要参数,直接影响陀螺的角随机游走,因此准确快速地测量极化场有利于研制性能更优的原子气室。为了实现Rb-Xe体系的核磁共振陀螺仪快速、原位测量Xe的极化场,提出了利用Rb电子顺磁共振频移测量Xe极化场的方法。通过激励磁场翻转Xe极化场,推导了估算Xe极化场的简单公式。实验测量了在典型核磁共振陀螺仪装置中,10nT量级的Xe极化场,结果与理论计算相符。表明这种方法能够快速有效地在核磁共振陀螺仪原位测量Xe的极化场。 展开更多
关键词 Xe极化场 原位测量 电子顺磁共振 核磁共振陀螺仪 极化场旋转
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^(129)Xe通气功能MRI与肺部病灶类型关联研究
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作者 陈琪 李海东 +10 位作者 方媛 沈路阳 刘无己 罗明 李业成 张鸣 赵修超 石磊 周倩 韩叶清 周欣 《波谱学杂志》 CAS 2024年第3期276-285,共10页
本研究旨在探索^(129)Xe通气功能MRI与肺部病灶类型之间的关联.我们对143例患者进行^(129)Xe通气功能MRI和肺部CT扫描,并分析了肺叶水平的通气功能与肺部病灶类型之间的关系.结果显示,大部分肺叶(74.6%)^(129)Xe肺通气功能MRI和CT结果一... 本研究旨在探索^(129)Xe通气功能MRI与肺部病灶类型之间的关联.我们对143例患者进行^(129)Xe通气功能MRI和肺部CT扫描,并分析了肺叶水平的通气功能与肺部病灶类型之间的关系.结果显示,大部分肺叶(74.6%)^(129)Xe肺通气功能MRI和CT结果一致.通气功能损伤与CT病灶类型相关,且混合疾病和肺气肿/肺大疱更易引起肺通气功能障碍.此外,我们的研究显示不同肺部病灶类型会呈现出不同的通气模式.即^(129)Xe通气功能MRI和肺部CT能够提供互补信息.本研究的初步结果将为肺部病灶引起的通气功能损伤评估提供数据支持,为临床影像学诊断提供更多的参考依据,有助于优化肺部疾病的诊断和治疗. 展开更多
关键词 超极化^(129)Xe 肺部通气功能磁共振成像 肺部CT 肺部疾病
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