检索结果-南通市图书馆

spatial and seasonal Variations of Mass and Chemical Composition for PM10 in xi'an,China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spatial and Seasonal Variations of Mass and Chemical Composi...

Analysis of Charge Exchange spectrum During Lower Hybrid Current Drive on HT-7 Tokamak

十一届全国气溶胶会议暨第十届海峡两岸气溶胶技术研讨会

作者： T.Zhang J.J.Cao s.x.liu s.x.Yang sKLLQG Institute of Earth EnvironmentChinese Academy of Sciences Institute of Global Environmental Change Xi’an Jiaotong University

PM10 samples were simultaneously collected in six sampling sites during spring, summer, autumn and winter in 2010, and then their chemical composition, including elements of Ti, Mn, Fe, Zn, As and Pb, water-soluble inorganic ions of Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, and sO42-, organic carbon(OC), and element carbon(EC), were determined to evaluate the PM10 levels and their chemical characteristics in xi’an. The annual mean value of PM10 mass concentration was 302.6 μg m-3 at shengzhengfu site(north)、293.1 μg m-3 at Weidianji site(western)、266.3 μg m-3 at Dihuansuo site(south)、223.7 μg m-3 at Chanba site(eastern) and 254.9 μg m-3 at Gaolin site(upwind zone)、211.1 μg m-3 at Heihe site(downwind zone). The CD values calculated for the urban and background stations were 0.25, 0.20, 0.17 and 0.22 during spring, summer, autumn, and winter, respectively. Low CD values reflect the similarities in the composition of the aerosol between sites. The PMF results revealed that construction dust(22.7%) contributed significantly to the detected PM10 mass, followed by secondary aerosol(22.3%), motor vehicle(18.3%), coal combustion(17.8%), soil dust(13.1%) and biomass burning(5.8%) at the urban site.

关键词： PM10 chemical composition mass balance

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中国核科技报告 1999年第S4期 363-364页

作者： s.x.liu B.N.Wan G.L.Kuang x.Gao L.Q.Hu A.L.Yao P.J.Qin x.Z.Gong L.Chen Y.J.shi J.G.Li Institute of Plasma Physics Hefei Anhui 230031 P.R.China Academia sinica

This paper presents the experimental results by charge-exchange fast neutral particle measurements with neutral particle energy analyzer (NPA) in lower hybrid current drive (LHCD) experiments, which firstly show ion heating of LHCD on HT-7 superconducting tokamak. The LHCD experiments on HT-7 tokamak were carried out with the following paramenters: B=1.8 T, I=110～150 kA, n=(0.8～2)×10cm. The lower hybrid wave (LHW) had a pulse duration of 360ms and power of about 300 kW with an peak of parallel refractive index of N=2.9.

关键词： LHCD Analysis of Charge Exchange spectrum During Lower Hybrid Current Drive on HT-7 Tokamak HT

Edge supercurrent in Josephson junctions based on topological materials

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 1-12页

作者： Junjie Qi Chui-Zhen Chen Juntao song Jie liu Ke He Qing-Feng sun x.C.xie Beijing Academy of Quantum Information sciences Beijing 100193China school of Physical science and Technology Soochow UniversitySuzhou 215006China Institute for Advanced study Soochow UniversitySuzhou 215006China College of Physics and Hebei Advanced Thin Films Laboratory Hebei Normal UniversityShijiazhuang 050024China school of Physics Xi’an Jiaotong UniversityMinistry of Education Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed MatterXi’an 710049China state Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Frontier science Center for Quantum Information Beijing 100084China Hefei National Laboratory Hefei 230088China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Interdisciplinary Center for Theoretical Physics and Information sciences Fudan UniversityShanghai 200433China

The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum *** Josephson effect serves as a useful probe for edge superconductivity in these hybrid topological *** Josephson junctions based on topological materials,supercurrents exhibit unique quantum interference patterns,including the conventional Fraunhofer oscillations,theΦ_(0)-periodic oscillation,and the 2Φ_(0)-periodic oscillation in response to the external magnetic field(Φ_(0)=h/2e is the flux quantum,h the Planck constant,and e the electron charge).These interference patterns stem from varied Andreev reflection mechanisms and the associated current density *** review seeks to comprehensively examine the theoretical and experimental advancements in understanding the quantum interference patterns of edge supercurrents in Josephson junctions based on quantum spin Hall,quantum Hall,and quantum anomalous Hall systems.

关键词： quantum Hall effect quantum spin Hall effect quantum anomalous Hall effect Josephson junction edge supercurrent Andreev reflection

Characteristics of elemental carbon and organic carbon in PM2.5 during winter in rural area of Guanzhong Plain

在线全文

学校读者我要写书评

暂无评论

Characteristics of elemental carbon and organic carbon in PM...

Anomalous open orbits in Hofstadter spectrum of Chern insulator

第五届海峡两岸气溶胶技术研讨会

作者： C.s.Zhu~(1,3) J.J.Cao~(1,2*) Z.x.shen~2 s.x.liu~(1,3) (~1 state Key Laboratory of Loess &(?)ternary Geology,Institute of Earth Environment,Chinese Academy of sciences,xi’an,China) (~2 Department of Environmental science &(?)echnology,xi’an Jiaotong University,xi’an,China ~3 Graduate school,Chinese Academy of sciences,Beijing,China)

Three rural sites (LT、WN and Hx) located in Guanzhong Plain were selected with a view to characterize both indoor and outdoor concentrations of organic carbon (OC) and elemental carbon (EC) using a thermal optical reflectance (TOR) *** OC and EC concentrations and their contributions to PM mass,as well as correlation between OC and EC,were investigated in *** PM,the average 24-hr outdoor mass concentration was 267μg/m,whilst those of which for OC and EC were 58.6μg/m and 6.6μg/m respectively,accounting for 22% and 2.5% of the outdoor PM *** average 24-hr PM indoor mass concentration was 237μg/m,and the concentrations of which indoor OC and EC were 61μg/m and 6.2μg/m account for 26% and 2.6% *** average ratio of indoor to outdoor concentrations (I/O ratio) of PM2.5 was *** average I/O ratios of OC and EC were 1.04 and 0.94 respectively. Indoor PM levels tended to be the highest at WN,and outdoor levels to be the highest at *** OC level seemed to be the highest at Hx for both indoors and *** LT and Hx,EC was higher outdoors than *** the contrary,EC was lower than OC at *** could be due to the influence of indoor and outdoor sources and air exchange rates.

关键词： Elemental carbon Organic carbon Guanzhong Plain

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah F.Q.Yuan Hua Jiang Haiwen liu x.C.xie Center for Advanced Quantum studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematics UC Berkeley Institute for Nanoelectronic Devices and Quantum Computing Fudan University International Center for Quantum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of Chern insulator can enrich the content of its Hofstadter butterfly spectra, which is closely related to recent experiments in twisted bilayer graphene and cold atom systems. We investigate the Hofstadter spectrum for various models of Chern insulators under a rational flux φ0/q, here φ0=h/e and q being an integer. We find the number of splitting subbands is |q-C| with C denoting the Chern number of parent band. Importantly, anomalous open-orbital subbands with Chern numbers q-1 and-q-1 emerge unexpectedly, which are beyond the parameter window（-q/2, q/2） of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum, identifying as a new type of topological phase transition. These novel findings not only pinpoint the peculiar Hofstadter spectrum of Chern insulator, but also provide routes to study exotic characteristics beyond the Landau level physics.

关键词： Hofstadter spectrum topological phase transition open orbit

同方期刊数据库

Arsenic methylation and microbial communities in paddy soils under alternating anoxic and oxic conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental sciences 2025年第2期148卷 468-475页

作者： Jing liu Rui Pei Runzeng liu Chuanyong Jing Wenjing liu shandong Key Laboratory of Environmental Processes and Health School of Environmental Science and EngineeringShandong UniversityQingdao 266237China state Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Arsenic(As)methylation in soils affects the environmental behavior of As,excessive accumulation of dimethylarsenate(DMA)in rice plants leads to straighthead disease and a serious drop in crop *** the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food ***,soils including unarsenic contaminated(N-As),low-arsenic(L-As),medium-arsenic(M-As),and high-arsenic(H-As)soils were incubated under continuous anoxic,continuous oxic,and consecutive anoxic/oxic treatments respectively,to profile arsenic methylating process and microbial species involved in the As *** anoxic-oxic(A-O)treatment,methylated arsenic was significantly increased once oxygen was introduced into the incubation *** methylated arsenic concentrations were up to 2-24 times higher than those in anoxic(A),oxic(O),and oxic-anoxic(O-A)treatments,under which arsenic was methylated slightly and then decreased in all four As concentration *** fact,the most plentiful arsenite s-adenosylmethionine methyltransferase genes(arsM)contributed to the increase in As ***(40.8%-62.4%),Firmicutes(3.5%-15.7%),and Desulfobacterota(5.3%-13.3%)were the major microorganisms related to this *** microbial increasedmarkedly and played more important roles after oxygen was introduced,indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic(flooding)and oxic(drainage)*** novel findings provided newinsights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.

关键词： Arsenic methylation Anoxic-oxic straighthead disease arsM gene Microbial community

Influence of a non-free field subsurface seismic history on the liquefaction resistance of sandy soils

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2025年第1期24卷 53-68页

作者： liu Liteng Wang xiaolei liu Run liu Libo Cao Zhipeng Zhang Fan College of Civil Engineering Hebei University of EngineeringHandan 056038China Institute of Geotechnical Engineering Tianjin UniversityTianjin 300072China

seismic-induced liquefaction of sandy soils can fail foundations in the vicinity of *** investigate the effect of a non-free field subsurface seismic history on the ability of saturated sandy soils to resist liquefaction,four shaking events with different accelerations were input to the sandy soils in the *** results of the study revealed that:(1)shallow soils that are not free-field undergo acceleration amplification effects after being subjected to seismic loading.(2)Building overburden pressure reduces the sensitivity of the shallow soils directly below in small and moderate earthquakes,which are more prone to rearranging and forming unstable structures under strong seismic *** excess pore pressure response on the load side resembles that of a free site,with the depth range of the liquefaction strength of soils affected by the seismic history,increasing progressively as input seismic intensity increases.(3)After experiencing earthquakes of different intensities,the excess pore pressure directly below the building overburden pressure at 0.1 m and 0.2 m is greater than that at the *** the same time,the side of the building structure is more prone to liquefaction than the soil directly below it.

关键词： non-free site seismic history liquefaction resistance excess pore pressure shaking table test

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： xinyuan Wang Fan Zhang xingyu Zhou Qian Wang Changyu liu Yangyang liu Hui Wang xiaojie liu Key Laboratory of synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127ShaanxiChina

Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory (DFT) and finite element simulations show that incorporating sO_(4)^(2-)into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na_(3)V_(2)(PO_(4))_(1.95)(sO_(4))_(0.05)O_(2)F(VPs-1) is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g^(-1)) and cycling stability (111.0 mAh g^(-1)capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPs-1//sbsn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging sodium-ion battery Fluorophosphate Cathode

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： Hui Wang shuang Chen xuming liu Qin Zhang xin liu Polymeric and soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina Polymeric and soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes,and ***,inherent weaknesses in ionic conductivity,mechanical properties,and water retention of hydrogel electrolytes seriously hinder their *** by the hardness conversion of sea cucumber skin,a conductivity and mechanics dual-tunable salt gel electrolyte is successfully *** salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate(sAT).Meanwhile,the salt gels spontaneously grow a layer of“armor”through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***,this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance:258.6 mF cm^(-2)),and the capacitance retention rate could still reach 86.9%after 3000 cycles at high ***,the salt gel supercapacitor is potentially used in over-heat alarm *** is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics,and flexible robots.

关键词： supercapacitors salt gels Reversible phase transition Post-tuning Conductivity switching