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An Analysis of the Air Parcel Trajectories of Long-Range Transport at Shanghai
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作者 邵德民 张维 +3 位作者 沈爱华 陈雪琴 付哲民 何珍珍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期346-350,共5页
1.INTRODUCTION Acid rain observations show that acid cloud water in Shanghai region appears not only
关键词 ACID An Analysis of the Air Parcel Trajectories of long-range transport at Shanghai
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An overview of emissions of SO2 and NOx and the long-range transport of oxidized sulfur and nitrogen pollutants in East Asia 被引量:8
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作者 Yu Qu Junling An +1 位作者 Youjiang He Jun Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第6期13-25,共13页
The long-range transport of oxidized sulfur(sulfur dioxide(SO2) and sulfate) and oxidized nitrogen(nitrogen oxides(NOx ) and nitrate) in East Asia is an area of increasing scientific interest and political con... The long-range transport of oxidized sulfur(sulfur dioxide(SO2) and sulfate) and oxidized nitrogen(nitrogen oxides(NOx ) and nitrate) in East Asia is an area of increasing scientific interest and political concern. This paper reviews various published papers, including ground- and satellite-based observations and numerical simulations. The aim is to assess the status of the anthropogenic emissions of SO2 and NOx and the long-range transport of oxidized S and N pollutants over source and downwind region. China has dominated the emissions of SO2 and NOx in East Asia and urgently needs to strengthen the control of their emissions, especially NOx emissions. Oxidized S and N pollutants emitted from China are transported to Korea and Japan, due to persistent westerly winds, in winter and spring.However, the total contributions of China to S and N pollutants across Korea and Japan were not found to be dominant over longer time scales(e.g., a year). The source–receptor relationships for oxidized S and N pollutants in East Asia varied widely among the different studies. This is because:(1) the nonlinear effects of atmospheric chemistry and deposition processes were not well considered, when calculating the source–receptor relationships;(2) different meteorological and emission data inputs and solution schemes for key physical and chemical processes were used; and(3) different temporal and spatial scales were employed. Therefore, simulations using the same input fields and similar model configurations would be of benefit, to further evaluate the source–receptor relationships of the oxidized S and N pollutants. 展开更多
关键词 long-range transport Sulfate Nitrate East Asia Source–receptor relationships
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COMPARISON OF AEROSOL CHARACTERISTICS OVER MAINLAND OF CHINA AND WESTERN PACIFIC AND ITS LONG-RANGE TRANSPORT
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作者 温玉璞 杨绍晋 +5 位作者 杨亦男 陈冰茹 周明煜 郑月明 张子瑜 于鸿健 《Acta meteorologica Sinica》 SCIE 1991年第2期160-170,共11页
Based on the aerosol data obtained at Shangdianzi regional background monitoring station together with the air trajectory analysis,the chemical constituents of the aerosol from the different sources are discussed and ... Based on the aerosol data obtained at Shangdianzi regional background monitoring station together with the air trajectory analysis,the chemical constituents of the aerosol from the different sources are discussed and compared with the acrosol samples collected over the western Pacific.The results show that the relative mass concentrations of the crustal and pollutant elements in the aerosol collected over the ocean are higher than those being observed at Shangdianzi in particle size above 4.7μm and below 0.65μm in diameter.The variations of the enrichment factors of these elements in marine aerosol with particle size are different from those in shang- dianzi's samples.The former enrichment factors are evidently higher than the latter above 1.1 μm in diameter. On the basis of the comparative research,the long-range transport processes of aerosol particles are discussed. 展开更多
关键词 marine aerosol enrichment factor long-range transport
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Long-range transport of organic aerosol to Cape Hedo,Japan
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作者 Xiaoxiu Lun Akinori Takami +2 位作者 Weifang Ma Akio Shimono Shiro Hatakeyama 《Particuology》 SCIE EI CAS CSCD 2014年第2期35-41,共7页
An investigation at Cape Hedo, Japan, from 2005 to 2006, focused on the long-range transport of organic aerosol (OA) from the Asian continent. An Aerodyne aerosol mass spectrometer was used to investigate the OA dat... An investigation at Cape Hedo, Japan, from 2005 to 2006, focused on the long-range transport of organic aerosol (OA) from the Asian continent. An Aerodyne aerosol mass spectrometer was used to investigate the OA data collected over the study. OA concentrations were low from July to September and peaked during March and April. Based on air mass origins, four OA source regions were identified: northern China, southern China, Japan, and Korea. OA concentrations measured at Cape Hedo from the four sources did not exhibit large differences. Conversely, the frequencies of the air masses reaching Cape Hedo from the different regions varied considerably. Northern China was identified as the primary source of organic aerosols at Cape Hedo. Examination of variations in the ratio of m/z 44 to OA concentrations with transport time showed that OAs were partially oxidized during transport 展开更多
关键词 long-range transportOrganic aerosolSource contributionOkinawa
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Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production 被引量:2
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作者 Man Yang Jing Mei +3 位作者 Yujing Ren Jie Cui Shuhua Liang Shaodong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期502-509,I0011,共9页
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He... The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts. 展开更多
关键词 Bimetallic single-atom catalyst long-range electron synergy Charge separation/transfer Carbon nitride Hydrogen production
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Generalized uncertainty principle from long-range kernel effects:The case of the Hawking black hole temperature
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作者 Rami Ahmad El-Nabulsi Waranont Anukool 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期153-156,共4页
We prove the existence of an analogy between spatial long-range interactions,which are of the convolution-type introduced in non-relativistic quantum mechanics,and the generalized uncertainty principle predicted from ... We prove the existence of an analogy between spatial long-range interactions,which are of the convolution-type introduced in non-relativistic quantum mechanics,and the generalized uncertainty principle predicted from quantum gravity theories.As an illustration,black hole temperature effects are discussed.It is observed that for specific choices of the moment's kernels,cold black holes may emerge in the theory. 展开更多
关键词 long-range kernel effects generalized uncertainty principle
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Topological properties of tetratomic Su-Schrieffer-Heeger chains with hierarchical long-range hopping
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作者 李冠强 王博涵 +2 位作者 唐劲羽 彭娉 董亮伟 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期469-476,共8页
We propose a new generalized Su–Schrieffer–Heeger model with hierarchical long-range hopping based on a onedimensional tetratomic chain. The properties of the topological states and phase transition, which depend on... We propose a new generalized Su–Schrieffer–Heeger model with hierarchical long-range hopping based on a onedimensional tetratomic chain. The properties of the topological states and phase transition, which depend on the cointeraction of the intracell and intercell hoppings, are investigated using the phase diagram of the winding number. It is shown that topological states with large positive/negative winding numbers can readily be generated in this system. The properties of the topological states can be verified by the ring-type structures in the trajectory diagram of the complex plane. The topological phase transition is strongly related to the opening(closure) of an energy bandgap at the center(boundaries) of the Brillouin zone. Finally, the non-zero-energy edge states at the ends of the finite system are revealed and matched with the bulk–boundary correspondence. 展开更多
关键词 generalized Su-Schrieffer-Heeger model tight-binding approximation topological phase transition long-range hopping winding number edge state
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Identification of the lysine and histidine transporter family in Camellia sinensis and the characterizations in nitrogen utilization 被引量:1
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作者 Wei Huang Danni Ma +9 位作者 Fawad Zaman Xulei Hao Li Xia E Zhang Pu Wang Mingle Wang Fei Guo Yu Wang Dejiang Ni Hua Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期273-287,共15页
In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen wit... In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen with a relatively high level of amino acids.However,systematic identification and molecular characterization of the LHT gene family has rarely been reported in tea plants.In this study,22 CsLHTs were identified from the‘Shuchazao’genome and classified into two groups.The modeled three-dimensional structure and the conserved domains presented a high similarity among the LHTs proteins.Moreover,it was predicted that a few genes were conserved through the analysis of the physiochemical characters,structures and cis-elements in promoters.The expression patterns in tea plants revealed that CsLHT7 was mainly expressed in the roots,and CsLHT4 and CsLHT11 exhibited relatively high expression in both the roots and leaves.Moreover,the expression of all three genes could be induced by organic nitrogen.Additionally,heterogeneous expression of CsLHT4,CsLHT7 and CsLHT11 in Arabidopsis thaliana decreased the aerial parts biomass compared with that in WT plants while significantly increased the rosette biomass only for CsLHT11transgenic plants versus WT plants.Overall,our results provide fundamental information about CsLHTs and potential genes in N utilization for further analysis in tea plants. 展开更多
关键词 Camellia sinensis Nitrogen Lysine and histidine transporter(LHT)family
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Inward particle transport driven by biased endplate in a cylindrical magnetized plasma
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作者 盖跃 徐田超 +6 位作者 肖池阶 郭志彬 王晓钢 何任川 杨肖易 张祖煜 袁瑞鑫 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期126-130,共5页
The inward particle transport is associated with the formation of peaked density profiles,which contributes to improve the fusion rate and the realization of steady-state discharge.The active control of inward particl... The inward particle transport is associated with the formation of peaked density profiles,which contributes to improve the fusion rate and the realization of steady-state discharge.The active control of inward particle transport is considered as one of the most critical issues of magnetic confinement fusion.Recently,it is realized preliminarily by adding a biased endplate in the Peking University Plasma Test(PPT)device.The results reveal that the inward particle flux increases with the bias voltage of the endplate.It is also found that the profile of radial electric field(Er)shear is flattened by the increased bias voltage.Radial velocity fluctuations affect the inward particle more than density fluctuations,and the frequency of the dominant mode driving inward particle flux increases with the biased voltage applied to the endplate.The experimental results in the PPT device provide a method to actively control the inward particle flux using a biased endplate and enrich the understanding of the relationship between E_(r)×B shear and turbulence transport. 展开更多
关键词 inward particle transport biased endplate turbulent transport
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Impact of T_(i)/T_(e )ratio on ion transport based on EAST H-mode plasmas
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作者 刘建文 臧庆 +14 位作者 梁云峰 陈佳乐 邬潇河 Alexander KNIEPS 扈嘉辉 金仡飞 张斌 储宇奇 刘海庆 吕波 段艳敏 李妙辉 陈颖杰 龚先祖 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期68-78,共11页
At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heati... At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated H-mode plasmas. Nevertheless, recently it was found that the T_(i)/T_(e)ratio can increase further with the fraction of the neutral beam injection(NBI) power, which leads to a higher core ion temperature(Ti0). In NBI heating-dominant H-mode plasmas, the ion temperature gradient-driven modes become the most unstable modes.Furthermore, a strong and broad internal transport barrier(ITB) can form at the plasma core in high-power NBI-heated H-mode plasmas when the T_(i)/T_(e)ratio approaches ~1, which results in steep core Teand Tiprofiles, as well as a peaked neprofile. Power balance analysis shows a weaker Teprofile stiffness after the formation of ITBs in the core plasma region, where Ticlamping is broken,and the core Tican increase further above 2 keV, which is 80% higher than the value of Ticlamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of Ticlamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating. 展开更多
关键词 ion temperature clamping transport neutral beam injection STIFFNESS internal transport barrier
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A new review of single-ion conducting polymer electrolytes in the light of ion transport mechanisms
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作者 Yuqi Luo Lu Gao Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期543-556,I0012,共15页
With the depletion of fossil fuels and the demand for high-performance energy storage devices,solidstate lithium metal batteries have received widespread attention due to their high energy density and safety advantage... With the depletion of fossil fuels and the demand for high-performance energy storage devices,solidstate lithium metal batteries have received widespread attention due to their high energy density and safety advantages.Among them,the earliest developed organic solid-state polymer electrolyte has a promising future due to its advantages such as good mechanical flexibility,but its poor ion transport performance dramatically limits its performance improvement.Therefore,single-ion conducting polymer electrolytes(SICPEs)with high lithium-ion transport number,capable of improving the concentration polarization and inhibiting the growth of lithium dendrites,have been proposed,which provide a new direction for the further development of high-performance organic polymer electrolytes.In view of this,lithium ions transport mechanisms and design principles in SICPEs are summarized and discussed in this paper.The modification principles currently used can be categorized into the following three types:enhancement of lithium salt anion-polymer interactions,weakening of lithium salt anion-cation interactions,and modulation of lithium ion-polymer interactions.In addition,the advances in single-ion conductors of conventional and novel polymer electrolytes are summarized,and several typical highperformance single-ion conductors are enumerated and analyzed in what way they improve ionic conductivity,lithium ions mobility,and the ability to inhibit lithium dendrites.Finally,the advantages and design methodology of SICPEs are summarized again and the future directions are outlined. 展开更多
关键词 Lithium metal batteries Single-ion conductor Polymer electrolytes Ion transport mechanism Li-ion transport number
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Long radial coherence of electron temperature fluctuations in non-local transport in HL-2A plasmas
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作者 石中兵 方凯锐 +14 位作者 李景春 邹晓岚 卢兆旸 闻杰 王占辉 丁玄同 陈伟 杨曾辰 蒋敏 季小全 佟瑞海 李永高 施陪万 钟武律 许敏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期413-420,共8页
The dynamics of long-wavelength(kθ<1.4 cm^(-1)),broadband(20 kHz–200 kHz)electron temperature fluctuations(Te/Te)of plasmas in gas-puff experiments are observed for the first time in HL-2A tokamak.In a relatively... The dynamics of long-wavelength(kθ<1.4 cm^(-1)),broadband(20 kHz–200 kHz)electron temperature fluctuations(Te/Te)of plasmas in gas-puff experiments are observed for the first time in HL-2A tokamak.In a relatively low density(ne(0)■0.91×10^(19)m^(-3)–1.20×10^(19)m^(-3))scenario,after gas-puffing the core temperature increases and the edge temperature drops.On the contrary,temperature fluctuation drops at the core and increases at the edge.Analyses show the non-local emergence is accompanied with a long radial coherent length of turbulent fluctuations.While in a higher density(ne(0)?1.83×10^(19)m^(-3)–2.02×10^(19)m^(-3))scenario,the phenomena are not observed.Furthermore,compelling evidence indicates that E×B shear serves as a substantial contributor to this extensive radial interaction.This finding offers a direct explanatory link to the intriguing core-heating phenomenon witnessed within the realm of non-local transport. 展开更多
关键词 nuclear fusion non-local transport TOKAMAK gas-puffing
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Transport properties of Hall-type quantum states in disordered bismuthene
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作者 周娇娇 余江应 +1 位作者 成淑光 江华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期16-23,共8页
Bismuthene,an inherently hexagonal structure characterized by a huge bulk gap,offers a versatile platform for investigating the electronic transport of various topological quantum states.Using nonequilibrium Green'... Bismuthene,an inherently hexagonal structure characterized by a huge bulk gap,offers a versatile platform for investigating the electronic transport of various topological quantum states.Using nonequilibrium Green's function method and Landauer-Büttiker formula,we thoroughly investigate the transport properties of various Hall-type quantum states,including quantum spin Hall(QSH)edge states,quantum valley Hall kink(QVHK)states,and quantum spin-valley Hall kink(QSVHK)states,in the presence of various disorders.Based on the exotic transport features,a spin-valley filter,capable of generating a highly spin-and valley-polarized current,is proposed.The valley index and the spin index of the filtered QSVHK state are determined by the staggered potential and the intrinsic spin-orbit coupling,respectively.The efficiency of the spin-valley filter is supported by the spacial current distribution,the valley-resolved conductance,and the spin-resolved conductance.Compared with a sandwich structure for QSVHK,our proposed spin-valley filter can work with a much smaller size and is more accessible in the experiment. 展开更多
关键词 electronic transport bismuthene spin-valley filter
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Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt
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作者 Amira Samy Mustafa Eissa +2 位作者 Seham Shahen Moustafa M.Said Rabab M.Abou-shahaba 《Acta Geochimica》 EI CAS CSCD 2024年第1期16-39,共24页
The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 8... The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI < 1). The isotopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems. 展开更多
关键词 Groundwater geochemistry Seawater intrusion Solute transport SEAWAT
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Impact of Long-range Desert Dust Transport on Hydrometeor Formation over Coastal East Asia
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作者 Zhenxi ZHANG Wen ZHOU +1 位作者 Mark WENIG Liangui YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第1期101-115,共15页
Model simulations and hydrological reanalysis data for 2007 are applied to investigate the impact of long-range desert dust transport on hydrometeor formation over coastal East Asia. Results are analyzed from Hong Kon... Model simulations and hydrological reanalysis data for 2007 are applied to investigate the impact of long-range desert dust transport on hydrometeor formation over coastal East Asia. Results are analyzed from Hong Kong and Shanghai, which are two representative coastal cities of East Asia. Long-range desert dust transport impacts mainly spring and summer clouds and precipitation over coastal East Asia. In spring, clouds and precipitation come mainly from large-scale condensation and are impacted mainly by dust from the Gobi, Sahara, and Thar deserts. These desert dusts can participate in the precipitation within and below the clouds. At lower latitudes, the dust particles act mainly as water nuclei. At higher latitudes, they act as both water nuclei and ice nuclei. The effect of Gobi, Sahara, and Thar dust on large-scale clouds and precipitation becomes stronger at higher latitudes. In summer, clouds and precipitation over coastal East Asia come mainly from convection and are impacted mainly by dust from the Taklamakan, Arabian, and Karakum-Kavir deserts. Most Taklamakan dust particles can participate in precipitation within convective clouds as ice nuclei, while Arabian and Karakum-Kavir dust particles participate only as water nuclei in precipitation below the clouds. The effect of Taklamakan dust on convective clouds and precipitation becomes stronger at lower latitudes. Of all the desert dusts, that from the Gobi and Taklamakan deserts has the relatively largest impact. Gobi dust impacts climate change in coastal East Asia by affecting spring water clouds at higher latitudes. 展开更多
关键词 DUST transport condensation nuclei hydrometeor East Asia
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Controlled thermally-driven mass transport in carbon nanotubes using carbon hoops
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作者 李耀隆 李松远 +1 位作者 王美芬 张任良 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期66-69,共4页
Controlling mass transportation using intrinsic mechanisms is a challenging topic in nanotechnology.Herein,we employ molecular dynamics simulations to investigate the mass transport inside carbon nanotubes(CNT)with te... Controlling mass transportation using intrinsic mechanisms is a challenging topic in nanotechnology.Herein,we employ molecular dynamics simulations to investigate the mass transport inside carbon nanotubes(CNT)with temperature gradients,specifically the effects of adding a static carbon hoop to the outside of a CNT on the transport of a nanomotor inside the CNT.We reveal that the underlying mechanism is the uneven potential energy created by the hoops,i.e.,the hoop outside the CNT forms potential energy barriers or wells that affect mass transport inside the CNT.This fundamental control of directional mass transportation may lead to promising routes for nanoscale actuation and energy conversion. 展开更多
关键词 molecular dynamics thermal drive nanotube hoop mass transport
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Nonreciprocal transport in the superconducting state of the chiral crystal NbGe_(2)
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作者 刘永来 许锡童 +6 位作者 何苗 赵海天 曾庆祺 杨星宇 邹优鸣 杜海峰 屈哲 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期161-165,共5页
Due to the lack of inversion,mirror or other roto-inversion symmetries,chiral crystals possess a well-defined handedness which,when combined with time-reversal symmetry breaking from the application of magnetic fields... Due to the lack of inversion,mirror or other roto-inversion symmetries,chiral crystals possess a well-defined handedness which,when combined with time-reversal symmetry breaking from the application of magnetic fields,can give rise to directional dichroism of the electrical transport phenomena via the magnetochiral anisotropy.In this study,we investigate the nonreciprocal magneto-transport in microdevices of NbGe_(2),a superconductor with structural chirality.A giant nonreciprocal signal from vortex motions is observed during the superconducting transition,with the ratio of nonreciprocal resistance to the normal resistanceγreaching 6×10^(5)T^(-1)·A^(-1).Interestingly,the intensity can be adjusted and even sign-reversed by varying the current,the temperature,and the crystalline orientation.Our findings illustrate intricate vortex dynamics and offer ways of manipulation on the rectification effect in superconductors with structural chirality. 展开更多
关键词 chiral crystals magnetochiral anisotropy superconducting vortex nonreciprocal transport
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Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining
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作者 LIU Lei LIU Jian-cheng +2 位作者 LI Xin XU Li-xin ZHANG Xiu-zhan 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期42-53,共12页
Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for... Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial applications.In the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle velocity.The hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow velocities.During transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture velocity.The qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were investigated.The local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic gradient.The effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport. 展开更多
关键词 deepsea mining vertical hydraulic transport experiment flow characteristics
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A mutation in the promoter of the yellow stripe-like transporter gene in cucumber results in a yellow cotyledon phenotype
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作者 Jiawei Pan Jia Song +3 位作者 Rahat Sharif Xuewen Xu Shutong Li Xuehao Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期849-862,共14页
Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast development.Herein,we identified a spontaneous mutant,yc412,i... Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast development.Herein,we identified a spontaneous mutant,yc412,in cultivated cucumber that exhibited yellow cotyledons.The yellow-lethal mutant was diagnosed with an abnormal chloroplast ultrastructure,and reduced photosynthetic capacity and pigment content.Through bulked segregant analysis-based whole-genome sequencing and fine genetic mapping,we narrowed the yellow cotyledons (yc) locus to a 96.8 kb interval on chromosome 3.By resequencing and molecular cloning,we showed that Csyc is a potential candidate gene,which encodes a yellow stripe-like (YSL) transporter.The T to C mutation in the promoter region of Csyc caused the yellow cotyledon phenotype in yc412.Compared to YZU027A (WT),the expression of Csyc was significantly downregulated in the cotyledons of yc412.Silencing of Csyc in cucumber via virus-induced gene silencing resulted in chlorotic leaves,mainly by suppressing the chlorophyll content.Furthermore,a comparative transcriptome analysis revealed that chloroplast-related genes and chlorophyll biosynthesis genes were significantly downregulated in yc412 cotyledons.Our results provide new insights into the molecular function of the YSL transporter in plant chloroplast development and chlorophyll synthesis. 展开更多
关键词 CUCUMBER yellow-lethal cotyledons chloroplast development yellow stripe-like transporter
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Valley-dependent transport in a mescoscopic twisted bilayer graphene device
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作者 史文萱 刘翰林 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期61-65,共5页
We study the valley-dependent electron transport in a four-terminal mesoscopic device of the two monolayer graphene nanoribbons vertically stacked together, where the intersection forms a bilayer graphene lattice with... We study the valley-dependent electron transport in a four-terminal mesoscopic device of the two monolayer graphene nanoribbons vertically stacked together, where the intersection forms a bilayer graphene lattice with a controllable twist angle. Using a tight-binding lattice model, we show that the longitudinal and transverse conductances exhibit significant valley polarization in the low energy regime for small twist angles. As the twist angle increases, the valley polarization shifts to the high energy regime. This arises from the regrouping effect of the electron band in the twisted bilayer graphene region. But for relatively large twist angles, no significant valley polarization is observed. These results are consistent with the spectral densities of the twisted bilayer graphene. 展开更多
关键词 twisted bilayer graphene valley-dependent transport graphene nanoribbon CONDUCTANCE
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