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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi Mohammad Sabaeian Department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on Laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium atom.To achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge approximation.Our findings corroborate prior observations by Wang et al[Wang and Eberly,Phys.Rev.Lett.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear polarization.As a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported results.Notably,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE

Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton

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Acta Oceanologica Sinica 2024年第2期43卷 23-33页

作者： Zihan Gao Zhi Chen Hongyi He Zhaofei Liu Chang Lu Hanyu Wang Yili Luo Ying Li Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China College of Geosciences China University of Petroleum-BeijingBeijing 102249China School of Earth Science and Resources China University of Geosciences(Beijing)Beijing 100083China

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 hel

关键词： helium Bohai Bay Basin destruction of the North China Craton fault Cenozoic volcanic rocks strong earthquake activity

Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au+ions and a capping agent

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Plasma Science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB José Mauricio A.CAIUT Bruno CAILLIER Laboratoire Diagnostics des Plasmas Hors Equilibre(DPHE) Universitéde ToulouseINU ChampollionAlbi 81000France Department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive species.These species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid solution.In this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit agglomerations.The formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink color.This was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPR)band.An investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold nanoparticles.Dynamic light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRD)was also employed to determine their crystallographic structure.The results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium DBD

On the helium bubble swelling in nano-oxide dispersion-strengthened steels

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Journal of Materials Science & Technology 2022年第10期105卷 172-181页

作者： Vladimir Krsjak Tielong Shen Jarmila Degmova Stanislav Sojak Erik Korpas Pavol Noga Werner Egger Bingsheng Li Vladimir Slugen Frank A.Garner Slovak University of Technology Faculty of Electrical Engineering and Information TechnologyInstitute of Nuclear and Physical EngineeringIlkovicova 3Bratislava 81219Slovakia Chinese Academy of Sciences Institute of Modern PhysicsLanzhou 730000China Slovak University of Technology Faculty of Materials Science and TechnologyAdvanced Technologies Research InstituteJana Bottu 2781/25Trnava 91724Slovakia Universität der Bundeswehr München Institut für Angewandte Physik und Messtechnik LRT2Werner-Heisenberg-Weg 39Neubiberg85577Germany Southwest University of Science and Technology State Key Laboratory for Environment-friendly Energy MaterialsMianyangSichuan 621010China Texas A&M University Nuclear Engineering DepartmentCollege StationTX 77843USA Radiation Effects Consulting LLC Richland WA 99354USA

The development of structural materials resistant to harsh radiation environments requires an in-depth understanding of the early stage of the aging processes.In radiation environments with high transmutation helium production rates such as in fusion and spallation applications,even materials with otherwise acceptable radiation stability may suffer from radiation embrittlement related to helium bubble formation.While theoretical modeling of helium-assisted cavity nucleation in pure metals and simple alloys provides some useful guidelines at the atomic scale level,these,however,do not overlap with the size resolution of available experimental techniques.In this study,we employed slow positron beam spectroscopy to characterize the nucleation and growth of nano-scale helium bubbles in martensitic steels strengthened by thermodynamically stable nano-oxide dispersoids.In combination with transmission electron microscopy,we experimentally characterized the evolution of helium bubbles from small clusters of radiation-induced vacancies to large cavities well resolvable by TEM.Superior radiation resistance of oxide-dispersion strengthened steels dominates only in the early stages of bubble evolution,where positron lifetime measurements provide a missing piece of the microstructural puzzle conventionally constructed by TEM.

关键词： Ion irradiation Bubble swelling helium Positron annihilation spectroscopy Oxide dispersion strengthened steels

Simulation study on thermal performance of two turns helium cryogenic oscillating heat pipe for superconducting accelerator

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Radiation Detection Technology and Methods 2023年第3期7卷 427-434页

作者： Yi Huo Changcheng Ma Jun Zhang Rui Huang Rui Ge University of Chinese Academy of Sciences BeijingChina Institute of High Energy Physics BeijingChina Hefei University of Technology HefeiChina

Purpose In recent years,with the further development of superconducting technology,superconducting devices have been applied in particle accelerators and synchrotron radiation light source devices.As a new type of heat transfer structure,helium cryogenic oscillating heat pipe can be used to balance local hot spots in superconductors and improve heat transfer performance.Methods In this paper,a two-dimensional two-turns helium cryogenic oscillating heat pipe model is established.The flow performance of helium cryogenic oscillating heat pipe was analyzed by CFD simulation.Results and conclusion The results show that the development of flow pattern in the helium cryogenic oscillating heat pipe first forms bubble flow under the heating of the evaporation section,and then gradually forms slug flow and annular flow.The process consists of initial stage,transition stage and running stage.In the running stage,the effective thermal conductivity of COHP oscillates around 15,000 W/(m·K).

关键词： Cryogenic oscillating heat pipe helium CFD simulation Superconducting accelerator

Precision spectroscopy of atomic helium

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National Science Review 2020年第12期7卷 1818-1827页

作者： Yu R.Sun Shui-Ming Hu Hefei National Laboratory for Physical Sciences at Microscale iChem CenterUniversity of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China

helium is a prototype three-body system and has long been a model system for developing quantum mechanics theory and computational methods.The fine-structure splitting in the 2;P state of helium is considered to be the most suitable for determining the fine-structure constant α in atoms.After more than 50 years of efforts by many theorists and experimentalists,we are now working toward a determination ofα with an accuracy of a few parts per billion,which can be compared to the results obtained by entirely different methods to verify the self-consistency of quantum electrodynamics.Moreover,the precision spectroscopy of helium allows determination of the nuclear charge radius,and it is expected to help resolve the ’proton radius puzzle’.In this review,we introduce the latest developments in the precision spectroscopy of the helium atom,especially the discrepancies among theoretical and experimental results,and give an outlook on future progress.

关键词： precision spectroscopy helium quantum electrodynamics fine-structure constant nuclear charge radius

helium—Charged Titanium Films Deposited by Pulsed Laser Deposition in an Electron—Cyclotron—Resonance helium Plasma Environment

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Chinese Physics Letters 2003年第3期20卷 386-388页

作者：金钦华凌浩等 LaboratoryofAppliedIonBeamPhysics InstituteofModernPhysicsFudanUniversityShanghai200433 StateKeyLaboratoryforAdvancedPhotonicMaterialsandDevices DepartmentofOpticalScienceand

Titanium thin films incorporated with helium are produced by pulsed laser deposition in an electron cyclotron resonance helium plasma environment. helium is distributed evenly in the film and a relatively high He/Ti atomic ratio (~20%) is obtained from the proton backscattering spectroscopy. This high concentration of helium leads to a surface blistering which is observed by scanning electron microscopy. Laser repetition rate has little influence on film characters. Substrate bias voltage is also changed for the helium incorporating mechanism study, and this is a helium ion implantation process during the film growth. Choosing suitable substrate bias voltage, one can avoid the damage produced by ion implantation, which is always present in general implantation case.

关键词： helium

helium and neon isotopic compositions in the ophiolites from the Yarlung Zangbo River,Southwestern China:The information from deep mantle

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Science China Earth Sciences 2007年第6期50卷 801-812页

作者： YE XianRen TAO MingXin YU ChuanAo ZHANG MingJie Institute of Geology and Geophysics Chinese Academy of SciencesLanzhou 730000China Department of Geology Lanzhou UniversityLanzhou 730000China

The ophiolites from the Yarlung Zangbo River (Tibet),Southwestern China,were analysed for the con-tents of helium and neon and their isotopic compositions by stepwise heating. The serpentinites from Bainang showed a high 3He/4He value of 32.66Ra (Ra is referred to the 3He/4He ratio in the present air) in 700 ℃ fraction. At lower temperature,all of the dolerites displayed as very high 3He/4He ratios as ones investigated for hotspots. It was clear that the high 3He/4He ratio was one of immanent characterics in the magma source formed the dolerites,suggesting that there was a large amount of deep mantle fluids in these rocks. In the three-isotope diagram of neon,the data points from the ophiolites of the Yarlung Zangbo River were arranged along the Loihi Line. This is in agreement with the characteristics of he-lium isotopes,revealing that the high-3He plume from deep mantle had played an important role in the formation of the Neo-Tethyan Ocean. The helium isotopic compositions in the basalts were far higher than atomospheric value but lower than the average value of MORB,although there were various de-grees of alteration. The possible reasons were that basaltic

关键词： Yarlung Zangbo River (Tibet) ophiolite helium neon isotope plume

helium Isotopic Composition of the Songduo Eclogites in the Lhasa Terrane,Tibet: Information from the Deep Mantle

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Journal of Earth Science 2019年第3期30卷 563-570页

作者： Zhaoli Li Jingsui Yang Tianfu Li Songyong Chen Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological Sciences

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.

关键词： eclogite helium isotopic composition HP/UHP metamorphic belt Lhasa terrane Qinghai-Tibet Plateau

An effective method to calculate the electron impact excitation cross sections of helium from ground state to a final channel in the whole energy region

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Chinese Physics B 2023年第11期32卷 194-200页

作者：孙瑞曾德灵金锐韩小英高翔李家明 Key Laboratory for Laser Plasmas Ministry of EducationSchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Institute of Applied Physics and Computational Mathematics Beijing 100088China Institute of Electron&Electronic Measurement Technology Shanghai Institute of Measurement and Testing TechnologyShanghai 201203China Max-Planck-Institut fur Kernphysik Saupfercheckweg 169117 HeidelbergGerman Department of Physics and Center for Atomic and Molecular Nanosciences Tsinghua UniversityBeijing 100084China

The electron impact excitation(EIE) cross sections of an atom/ion in the whole energy region are needed in many research fields, such as astrophysics studies, inertial confinement fusion researches and so on. In the present work, an effective method to calculate the EIE cross sections of an atom/ion in the whole energy region is presented. We use the EIE cross sections of helium as an illustration example. The optical forbidden 1^(1)S–n^(1)S(n = 2–4) and optical allowed 1^(1)S–n^(1)P(n = 2–4) excitation cross sections are calculated in the whole energy region using the scheme that combines the partial wave R-matrix method and the first Born approximation. The calculated cross sections are in good agreement with the available experimental measurements. Based on these accurate cross sections of our calculation, we find that the ratios between the accurate cross sections and Born cross sections are nearly the same for different excitation final states in the same channel. According to this interesting property, a universal correction function is proposed and given to calculate the accurate EIE cross sections with the same computational efforts of the widely used Born cross sections,which should be very useful in the related application fields. The datasets presented in this paper are openly available at https://***/10.57760/sciencedb.j00113.00142.

关键词： the electron impact excitation cross sections correction function helium the partial wave R-matrix plus the first Born approximation method