检索结果-南通市图书馆

Construction and Research Progress of the chinese Meridian Project in 2022–2023

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

空间科学学报 2024年第4期44卷 704-711页

作者： wang chi CHEN Zhiqing XU Jiyao National Space Science Center Chinese Academy of SciencesBeijing 100190

The chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two *** first phase of the CMP has been operating for more than a solar *** 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between *** construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second *** whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial *** science community is looking forward to the great contribution of the CMP to space weather and space physics research.

关键词： chinese Meridian Project(CMP) Magnetosphere Ionosphere Middle and upper atmosphere

Evidence of guide field magnetic reconnection in flapping current sheets

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第4期8卷 650-658页

作者： yunTian Hou SuPing Duan Lei Dai chi wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Based on current sheet flapping motion on 27 August 2018 in the dusk flank magnetotail,as recorded by instruments aboard Magnetospheric Multiscale(MMS)spacecraft,we present the first study of guide field reconnection observed in the flux rope embedded in kink-like flapping current sheets near the dusk-side flank of the *** more common magnetotail reconnections,which are symmetric,these asymmetric small-scale(λ_(i)~650 km)reconnections were found in the highly twisted current sheet when the direction normal to the sheet changes from the Z direction into the Y *** unique feature of this unusual reconnection is that the reconnection jets are along the Z direction-different from outflow in the X direction,which is the more usual *** vertical reconnection jet is parallel or antiparallel to the up-and-down motion of the tail’s current *** normalized reconnection rate R is estimated to be~*** results indicate that such asymmetric reconnections can significantly enlarge current sheet flapping,with large oscillation *** letter presents direct evidence of guide field reconnection in a highly twisted current sheet,characterized by enlarged current sheet flapping as a consequence of the reconnection outflow.

关键词： magnetic reconnection magnetotail current sheet

Study on surface discharge of nonlinear conductive epoxy resin/SrTiO3 composites in 80–300 K temperature zone

在线全文

学校读者我要写书评

暂无评论

High Voltage 2024年第1期9卷 117-126页

作者： yunqi Xing Bin wang Mingyang wang Jiakai chi Peng Jia Rongjin Huang State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina Key Laboratory of Electormagnetic Field and Electrical Apparatus Reliability of Hebei Province Hebei University of TechnologyTianjinChina Key Laboratory of Special Machine and High Voltage Apparatus(Ministry of Education) Shenyang University of TechnologyShenyangChina State Grid Tianjin High Voltage Company TianjinChina china Energy Engineering Group Tianjin Electric Power Design Institute Co. Ltd.TianjinChina CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryBeijingChina

Bisphenol F epoxy resin(EP)is often used in terminal current lead insulation of superconducting equipment because of its good insulation performance,high mechanical strength,good toughness at cryogenic temperatures,and resistance to cold shock and heat ***,due to the wide temperature range of 80–300 K and the strong electric field,the EP-N_(2)interface is prone to surface flashover,resulting in terminal insulation *** improve the reliability of the current lead insulation,non-linear conductive EP/strontium titanate(SrTiO_(3))composites were prepared by modification with nano *** changes of dielectric,surface discharge,flashover,and trap distribution characteristics of composite materials were studied,and the mechanism of SrTiO_(3)on the surface flashover of composite materials was *** results show that the conductivity of the composite increases with the rise of SrTiO_(3)filling content,and the amplitude of improvement is greater under the strong electric field,showing a more significant *** composite has a lower trap energy level and a greater number of shallow traps compared to pure EP,which accelerates surface charge detrapping and reduces charge accumulation,effectively enhancing the discharge and surface flashover voltage of the composite.

关键词： composites composite insulation

A redundant subspace weighting procedure for clock ensemble

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Physics B 2024年第4期33卷 435-442页

作者：徐海陈煜刘默驰王玉琢 National Institute of Metrology Beijing 100029China Key Laboratory of State Administration for Market Regulation Beijing 100029China china National Intellectual Property Administration Beijing 100088China

A redundant-subspace-weighting(RSW)-based approach is proposed to enhance the frequency stability on a time scale of a clock *** this method,multiple overlapping subspaces are constructed in the clock ensemble,and the weight of each clock in this ensemble is defined by using the spatial covariance *** superimposition average of covariances in different subspaces reduces the correlations between clocks in the same laboratory to some *** optimizing the parameters of this weighting procedure,the frequency stabilities of virtual clock ensembles are significantly improved in most cases.

关键词： weighting method redundant subspace clock ensemble time scale

Progress and challenge of functional single-atom catalysts for the catalytic oxidation of volatile organic compounds

在线全文

学校读者我要写书评

暂无评论

chinese Chemical Letters 2024年第9期35卷 83-91页

作者： Zeyu Jiang Yadi wang Changwei Chen chi He Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101408China

The catalytic oxidation of volatile organic compounds(VOCs)is of considerable significance for the sustainable development of the chemical industry;thus,considerable efforts have been devoted to the exploration of efficient catalysts for use in this *** this regard,the development and utilization of single-atom catalysts(SACs)in VOCs decomposition is a rapidly expanding research *** can be employed as potential catalysts for oxidizing VOC molecules due to their optimal utilization efficiency,unique atomic bonding structures,and unsaturated *** has been achieved,while the challenges surrounding precise regulation of the microstructures of SACs for improving their low-temperature efficiency,stability,and product selectivity under practical conditions are ***,elucidating structure-performance relationships and establishing intrinsic modulating mechanisms are urgently required for guiding researchers on how to synthesize effective and stable functional SACs ***,recent advances in the design and synthesis of functional SACs for application in the catalytic oxidation of VOCs are *** experimental and theoretical studies revealing higher efficiency,stability,and selectivity of as-prepared functional SACs are being ***,the future perspectives in terms of promising catalysts with multi-sized composite active sites and the illustration of intrinsic mechanism are *** rapid intelligent screening of applicable SACs and their industrial applications are also discussed.

关键词： Single-atom catalysts VOCs catalytic oxidation Hydrocarbon activation Oxygen species transformation Surface chemistry Intrinsic mechanism

Immersive visualization of 3D subsurface ground model developed from sparse boreholes using virtual reality(VR)

在线全文

学校读者我要写书评

暂无评论

Underground Space 2024年第4期17卷 188-206页

作者： Borui Lyu yu wang Department of Architecture and Civil Engineering City University of Hong KongKowloon 999077Hong KongChina

Analytics and visualization of multi-dimensional and complex geo-data,such as three-dimensional(3D)subsurface ground models,is critical for development of underground space and design and construction of underground structures(e.g.,tunnels,dams,and slopes)in engineering *** complicated 3D subsurface ground models now can be developed from site investigation data(e.g.,boreholes)which is often sparse in practice,it remains a great challenge to visualize a 3D subsurface ground model with sophisticated stratigraphic variations by conventional two-dimensional(2D)geological *** reality(VR)technology,which has an attractive capability of constructing a virtual environment that links to the physical world,has been rapidly developed and applied to visualization in various disciplines *** on the rapid development of VR,this study proposes a framework for immersive visualization of 3D subsurface ground models in geo-applications using VR *** 3D subsurface model is first developed from limited borehole data in a data-driven ***,a VR system is developed using related software and hardware devices currently available in the markets for immersive visualization and interaction with the developed 3D subsurface ground *** results demonstrate that VR visualization of the 3D subsurface ground model in an immersive environment has great potential in revolutionizing the geo-practices from 2D cross-sections to a 3D immersive virtual environment in digital era,particularly for the emerging digital twins.

关键词： Immersive visualization 3D subsurface model Virtual reality Virtual environment Interaction

Recent progress in all-inorganic tin-based perovskite solar cells:a review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china Chemistry 2024年第4期67卷 1117-1136页

作者： Minghao wang yu Shi School of Electronics and Information Engineering Wuxi UniversityWuxi 214105China Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816China

Recently,power conversion efficiency(PCE)of organic-inorganic hybrid perovskite solar cells(PSCs)has been improved to26.1%.However,the toxicity issue of lead still hinders the large-scale commercial production and application of lead(Pb)-based halide ***,environmentally friendly tin(Sn)-based perovskites have recently shown excellent *** them,the all-inorganic Sn-based perovskites,including CsSnX_(3) and Cs_(2)SnX_(6),have better stability,more suitable bandgap,and higher charge mobility,which have attracted more attention from researchers than organic-inorganic Sn-based hybrid ***,we review recent research progress on all-inorganic Sn-based perovskite materials and corresponding solar cell ***,we also summarize the current challenges and future research directions for this type of PSCs.

关键词： solar cells perovskite all-inorganic CsSnX_(3) Cs_(2)SnX_(6)

Steel-refractory reactions in lanthanum-,cerium-,and ytrium-added steels

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1473-1485页

作者： Jian Kang Hong-po wang yu wang College of Materials Science and Engineering Chongqing UniversityChongqing 400044China The State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

A systematic experimental study was conducted on the similarities and differences in the reactions between commonly used rare earth elements(REEs)and frequently used refractories in the steelmaking *** results indicate that the reaction behaviors of La,Ce,and Y with MgO,Al_(2)O_(3),and MgO·Al_(2)O_(3) crucibles differed *** consumption rates of La,Ce,and Y in the molten steel were in descending order of La>Ce>Y for smelting with all three kinds of *** the REEs reacted with the crucible,the contents of Mg and Al showed a trend of first increasing and then *** laboratory-scale smelting conditions,the reactions related to REEs were dominated by steel-crucible reactions,and the contact area between the unit mass of molten steel and refractory materials mainly determined the consumption rates of ***-and Ce-crucible reactions generated loose and porous reaction interfaces;however,Y-crucible reactions generated a dense Y_(2)O_(3) layer,dramatically suppressing the consumption rate of *** calculation indicated that the reactions between rare earth and different refractory materials were first-order *** crucible materials significantly affected the product type and morphology of the steel-crucible reaction interfaces,thereby influencing the consumption rate of *** reactions between REEs and refractories must be seriously considered,especially for small-scale smelting.

关键词： Rare earth Inclusion Refractory Thermodynamics Dynamics

Evolution Mechanism of Carbon Covalent Bond during Coal Activation Using Mixed Atmosphere of H_(2)O and CO_(2)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第5期33卷 1961-1973页

作者： wang Mingyue ZHANG Siyuan HAN Shaobo ZHANG chi REN Qiangqiang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 100049China State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China

Adequate destruction of the aromatic structure in coal is key to further reducing the emission of *** this research,activation reactions of Shenmu coal powder were carried out in a vertical tube *** study investigated the evolution mechanism of carbon covalent bonds during the activation process by altering the ratio of H_(2)O to CO_(2)in the activation *** theoretical validation was conducted through density functional *** two gas molecules follow different pathways to increase the reactivity of ***_(2)mainly participates in the cross-linking reaction by intensifying branching,while H_(2)O and char have lower adsorption energy barriers and are more likely to generate oxygen-containing functional *** molecules partially compete for active sites in a mixed gas atmosphere,but there is a synergism between the two *** synergism can be attributed to two *** inclusion of H_(2)O mitigates the generation of five-membered rings to a limited extent,while concurrently enhances the development of oxygen-containing functional *** oxygen-containing functional groups can effectively diminish the adsorption energy barrier associated with the interaction between gas molecules and char,consequently leading to a reduction in the energy demand for subsequent bond cleavage.

关键词： activation reaction carbon structure char CO_(2)/H_(2)O atmosphere density functional theory