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Pulsed octupole magnet for beam instability mitigation in rapid cycling synchrotron
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作者 Liang‑Sheng Huang Shou‑Yan Xu +7 位作者 Yun‑Tao Liu Yi‑Qin Liu Jian‑Liang Chen Chang‑Dong Deng Ming‑Yang Huang Li Rao Han‑Yang Liu Xin Qi 《Nuclear Science and Techniques》 2026年第1期107-118,共12页
The rapid cycling synchrotron(RCS)at the China spallation neutron source operates as a high-intensity proton accelerator.The coupled bunch instability was observed during RCS beam commissioning,which significantly lim... The rapid cycling synchrotron(RCS)at the China spallation neutron source operates as a high-intensity proton accelerator.The coupled bunch instability was observed during RCS beam commissioning,which significantly limited the beam power.To investigate the dynamics of instability under an increased beam power,a pulsed octupole magnet with a gradient of 900 T/m^(3) was developed.The magnet system integrated an octupole magnet with a pulsed power supply.The field was carefully measured to examine the performance before its installation into the tunnel.After the installation of the magnets,beam measurements were performed to confirm the effectiveness of the instability mitigation on an actual proton beam.The measurement results show that the instability can be suppressed using the pulsed octupole magnet,particularly at the highenergy stage in an acceleration cycle,meeting the requirements for stable operation of the accelerator.Additionally,when the instability is completely suppressed through chromaticity optimization,octupole magnets can significantly enhance the RCS transmission efficiency,which is crucial for controlling beam loss.The pulsed octupole magnet offers significant progress in beam stability in the RCS,providing valuable experience for further beam power enhancement. 展开更多
关键词 China spallation neutron source Rapid cycling synchrotron Coupled bunch instability Octupole magnet
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Tailoring anion-dominant solvation environment by steric-hindrance effect and competitive coordination for fast charging and stable cycling lithium metal batteries 被引量:2
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作者 Ruizhe Xu Anjun Hu +7 位作者 Zhen Wang Kai Chen Jingze Chen Wang Xu Gang Wu Fei Li Jian Wang Jianping Long 《Journal of Energy Chemistry》 2025年第6期35-43,I0002,共10页
The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate elect... The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes. 展开更多
关键词 Lithium metal batteries Fast charging Stable cycling Solvation structure
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The disappearance of children's cycling
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作者 秦虞 《疯狂英语(新悦读)》 2025年第10期44-46,78,共4页
1 A few decades ago,it was common to see groups of chil-dren riding bikes down quiet American streets.However,this scene is less likely to be seen today.In the 1990s,an average of 20.5 million children aged 7 to 17 ro... 1 A few decades ago,it was common to see groups of chil-dren riding bikes down quiet American streets.However,this scene is less likely to be seen today.In the 1990s,an average of 20.5 million children aged 7 to 17 rode bikes six or more times a year,according to the National Sporting Goods Association.By 2023,this number had dropped to about 10.9 million,with less than 5%of them riding frequently. 展开更多
关键词 riding CHILDREN DISAPPEARANCE STREETS cycling decades FREQUENCY
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A novel carbon-induced-porosity mechanism for improved cycling stability of magnesium hydride
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作者 Shuaijun Ding Yuqing Qiao +7 位作者 Xuecheng Cai Hongchao Wang Xun Shen Lidong Xu Yixuan Wen Fenglong Jiang Wei Zhou Tongde Shen 《Journal of Magnesium and Alloys》 2025年第3期1341-1352,共12页
MgH_(2) has been extensively studied as one of the most ideal solid hydrogen storage materials.Nevertheless,rapid capacity decay and sluggish hydrogen storage kinetics hamper its practical application.Herein,a Ni/C na... MgH_(2) has been extensively studied as one of the most ideal solid hydrogen storage materials.Nevertheless,rapid capacity decay and sluggish hydrogen storage kinetics hamper its practical application.Herein,a Ni/C nano-catalyst doped MgH_(2)(MgH_(2)–Ni/C)shows an improved hydrogen absorption kinetics with largely reduced activation energy.Particularly,the MgH_(2)–Ni/C displays remarkable cycling stability,which maintains a high capacity of 6.01 wt.%(98.8%of initial capacity)even after 50 full hydrogen ab/desorption cycles,while the undoped MgH_(2) counterpart retains only 85.2%of its initial capacity.Detailed microstructure characterizations clearly reveal that particle sintering/growth accounts primarily for the deterioration of cycling performance of undoped MgH_(2).By comparison,MgH_(2)–Ni/C can maintain a stable particle size with a growing porous structure during long-term cycling,which effectively increases the specific surface of the particles.A novel carbon-induced-porosity stabilization mechanism is proposed,which can stabilize the proportion of rapid hydrogen absorption process,thus dominating the excellent cycling performance of MgH_(2)–Ni/C.This study provides new insights into the cycling stability mechanism of carbon-containing Mg-based hydrogen storage materials,thus promoting their practical applications. 展开更多
关键词 Hydrogen storage materials Magnesium hydride cycling properties Particle stability Carbon-induced-porosity
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Anisotropy of V_(3)O_(7) nanobelts enables ultralong cycling life of magnesium ion battery
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作者 Xiu-Fen Ma Hong-Yi Li +7 位作者 Jing Tan Jinan Wang Jiang Diao Jili Yue Shuangshuang Tan Guangsheng Huang Jingfeng Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第4期1592-1601,共10页
Magnesium ion batteries(MIBs)are a promising alternative to lithium-ion batteries,which suffer from the short cycling life and sluggish Mg^(2+)diffusion kinetics of cathodes.Nano morphologies are used to shorten Mg^(2... Magnesium ion batteries(MIBs)are a promising alternative to lithium-ion batteries,which suffer from the short cycling life and sluggish Mg^(2+)diffusion kinetics of cathodes.Nano morphologies are used to shorten Mg^(2+)diffusion path for diffusion kinetics acceleration,but the cycling life is still unsatisfactory.Herein,the anisotropy of layered V_(3)O_(7)·1.9H_(2)O nanobelts is utilized to stabilize their structure during discharging/charging.The V_(3)O_(7)·1.9H_(2)O nanobelts grow along the preponderant migration direction of Mg^(2+),and the resulted axial migration of Mg^(2+)enables the stress caused by Mg^(2+)insertion to be decentralized in large zone,thus improving the cycling stability of V_(3)O_(7)·1.9H_(2)O nanobelts.The inserted Mg^(2+)cations bond with O atoms in adjacent V3O8 layers of V_(3)O_(7)·1.9H_(2)O,further stablizing the layered structure.Meanwhile,the axial migration of Mg^(2+)significantly reduces the charge transfer resistance at electrode/electrolyte interface,which accelerates the Mg^(2+)diffusion kinetics.Thus,the symmetric RMB assembled from V_(3)O_(7)·1.9H_(2)O nanobelts exhibits an ultralong cycling life of 11,000 cycles at 4 A g^(-1),alongside a high specific capacity of 137 mAh g^(-1)at 0.05 A g^(-1).According to our knowledge,this ultralong cycling life surpasses those of reported full RMBs.This strategy provides insight into the design of cathode materials with improved cycling lives. 展开更多
关键词 ANISOTROPY NANOBELTS cycling life Vanadium oxide Aqueous magnesium ion batteries
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Nitrogen-based redox couple regulated anionic redox to long-term cycling stability of Li and Mn-rich layered oxide cathode for Li-ion batteries
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作者 Zhijun Wu Chenchen Li +9 位作者 Panyu Gao Xin Zhang Yue Lin Xuebin Yu Yongfeng Liu Wenping Sun Yinzhu Jiang Mingxia Gao Hongge Pan Yaxiong Yang 《Journal of Materials Science & Technology》 2025年第12期157-166,共10页
Lithium and manganese-rich layered oxides(LMROs)have attracted extensive attention and are promising cathode materials for next-generation lithium ion batteries due to their high capacities and high energy densities.H... Lithium and manganese-rich layered oxides(LMROs)have attracted extensive attention and are promising cathode materials for next-generation lithium ion batteries due to their high capacities and high energy densities.However,LMRO cathode suffers from severe capacity and voltage fading originating from irreversible surface oxygen evolution.Herein,we propose a facile redox couple strategy by introducing nitroxyl radicals species to regulate the surface anionic redox reaction of LMRO cathode.Differential electrochemical mass spectroscopy,X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses demonstrate that during charge process,the peroxide ion O_(2)^(2−)on the surface generated from the oxidation of lattice O^(2-)could be reduced back to stable O^(2-)by redox couple in time,thus avoiding oxygen evolution and structure degradation,as well as enhancing bulk oxygen redox activity.The enhanced LMRO electrode delivers a high capacity of 220.3 mAh g^(−1)at 1 C.An excellent cycling stability with a capacity retention of 94.4%is achieved after 500 cycles,as well as a suppressed voltage decay with only 1.12 mV per cycle. 展开更多
关键词 Nitroxyl radicals Redox couple 2 2 6 6-tetramethylpiperidinooxy cycling stability Li and Mn-rich layered oxides
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Impact of broadleaf tree introduction on rhizosphere fungal communities and root phosphorus-cycling genes in conifers of near-natural transformed plantations
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作者 Zhanpeng Ye Chen Ning +4 位作者 Ting Liu Meirong Yan Wenyan Cai Jiyang Xiao Wende Yan 《Forest Ecosystems》 2025年第6期1236-1248,共13页
Phosphorus(P)is crucial for plant growth.However,its low availability in subtropical soils necessitates that trees rely on microorganisms for effective P acquisition.The introduction of broadleaf trees has been shown ... Phosphorus(P)is crucial for plant growth.However,its low availability in subtropical soils necessitates that trees rely on microorganisms for effective P acquisition.The introduction of broadleaf trees has been shown to facilitate P acquisition in coniferous plantations by altering the rhizosphere fungal communities.Despite this,functional shifts in these communities and the expression of root phosphorus cycling genes(PCGs)remain inadequately understood.This study investigated coniferous Pinus massoniana and Cunninghamia lanceolata plantations interplanted with broadleaf species associated with arbuscular mycorrhizal(AM)or ectomycorrhizal(ECM)fungi.Rhizosphere soil and fine roots from the conifers were analyzed to examine soil bioavailable P fractions,root mycorrhizal colonization,rhizosphere fungal community composition,enzyme function predictions,and root PCGs expression.We found that citric-P in rhizospheric soil of P.massoniana increased with the introduction of Quercus gilva(an ECM-associated tree species),whereas Bray-P content in the rhizosphere of C.lanceolata decreased upon the introduction of either Q.gilva or Phoebe zhennan(an ECM-associated tree species).Moreover,the relative abundance of saprophytic fungi(e.g.,Mortierella)increased following the introduction of broadleaf trees.Specifically,the introduction of Q.gilva was associated with elevated levels of organic P mineralization genes(e.g.,phoA)and enzymes(e.g.,phytases and acid phosphatase(ACP))in conifers.In contrast,the introduction of P.zhennan increased the expression of inorganic P solubilization genes(such as qppC in P.massoniana roots and ppa in C.lanceolata roots).Key contributors to P absorption in conifer roots included Cenococcum,Rhizopogon,and Glomus.This study advances our understanding of P cycling in coniferous rhizospheres and the dynamics of coexisting mycorrhizal tree systems,yielding valuable insights into sustainable management of plantation ecosystems. 展开更多
关键词 Near-natural transformed plantations Rhizosphere fungal community Phosphorus cycling genes Arbuscular mycorrhizal fungi Ectomycorrhizal fungi
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Microstructures and Properties of Modified Magnesium Phosphate Cement Mortar Prepared at Low Temperatures and Subjected to Freeze-Thaw Cycling at Early Ages
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作者 YUAN Jie ZHANG Zipeng +1 位作者 CHEN Xin HUANG Xin 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期427-438,共12页
Microstructures and properties of mortar using ammonium phosphate and potassium phosphate were tested and compared in this case.Moreover,two cementitious additions and two lightweight aggregates,including fly ash,redi... Microstructures and properties of mortar using ammonium phosphate and potassium phosphate were tested and compared in this case.Moreover,two cementitious additions and two lightweight aggregates,including fly ash,redispersible latex powder,ceramsite sand,and rubber powder,were respectively tried to be applied in magnesium ammonium phosphate cement mortar in order to modify the microstructures and properties.The experimental results show that potassium phosphate is not suitable for magnesium phosphate cement mortar for cold region construction purpose.Although fly ash can bring positive modification in the condition of normal temperature curing,it brings negative effects in the condition of sub-zero temperature curing.Either redispersible latex powder or ceramsite sand can improve the freeze-thaw cycling resistance of magnesium phosphate cement mortar in the conditions of low temperature coupled with freeze-thaw cycling,but only the ceramsite sand can improve both mechanical properties and freeze-thaw cycling resistance.The modification caused by ceramsite sand is mainly due to the exceptional bonding strength between hardened cement paste and the porous surface of ceramsite and the porous structure of ceramsite for the release of frost heave stress. 展开更多
关键词 magnesium phosphate cement sub-zero temperature freeze-thaw cycling early age
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The sources of subducting sediments at the Middle America Trench and their implications for the material cycling in subduction zone
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作者 Renjie Zhao Quanshu Yan +1 位作者 Haitao Zhang Xuefa Shi 《Acta Oceanologica Sinica》 2025年第5期25-40,共16页
Subducted sediments,as an integral part of subducted slab,can strongly influence the chemistry of volcanic arc lavas,and clarify the relationship between subduction input and arc output,which is the focus of the subdu... Subducted sediments,as an integral part of subducted slab,can strongly influence the chemistry of volcanic arc lavas,and clarify the relationship between subduction input and arc output,which is the focus of the subduction factory theory in the context of plate tectonics.In this study,we analyzed major and trace element compositions of the subducting sediments from two sites[Deep Sea Drilling Program(DSDP)Site 495 and Ocean Drilling Program(ODP)Site 1039]at the different locations along the Middle America Trench.The results showed that the sediments from these two sites are mainly composed of terrigenous material,carbonate components,and biogenic silicate in different proportions.In order to reduce the effects of the variations in subduction topography on the chemical composition of sediments,we recalculated the bulk subducted sediment composition at northern and southern Central America subduction zone,and identified the Nicaragua Fracture Zone as the dividing line for northern and southern subducting sediments at Middle America Trench.Compared to the global trench subducting sediment,both the subducting sediments from northern and southern Central America subduction zone exhibit lower contents of terrigenous material-controlled elements and are more enriched in the biogenic components-controlled elements.We suggested that the variations in both chemical compositions for sediments and subduction angles are responsible for the different contributions of subducting sediments to volcanic arc magmatism in the northern Central America. 展开更多
关键词 subducting sediments geochemistry material cycling northern and southern Central America
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Constriction-susceptible lithium support for fast cycling of solid-state lithium metal battery
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作者 Dong Sui Jiayi Liu 《Chinese Chemical Letters》 2025年第2期8-9,共2页
Recently,lithium metal batteries (LMBs) have been intensively explored owing to its high capacity and low potential of Li as the anode [1].However,challenging problems for LMBs easily occur during cycling process [2],... Recently,lithium metal batteries (LMBs) have been intensively explored owing to its high capacity and low potential of Li as the anode [1].However,challenging problems for LMBs easily occur during cycling process [2],e.g.,the growth of Li dendrites,the formation of unstable electrode-electrolyte interphases and side reactions inside the battery [3].These problems can lead to reduced battery performances and short circuit [4],which are tried to be solved by some strategies including various threedimensional (3D) supports for Li deposition,electrolyte additives and Li alloys.However,it is still difficult to solve the stability of Li cycling effectively.3D supports are demonstrated to be effective for tolerating the volume change during Li deposition. 展开更多
关键词 BATTERY LITHIUM cycling
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Correction to: Enhanced cycling stability of single-crystal LiNi_(0.83)Co_(0.07)Mn_(0.10)O_(2) by Li-reactive coating with H_(3)BO_(3)
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作者 Wen-Hui Hu Ya Yin +4 位作者 Ya Sun Guo-Xue Liu Shun-Yi Yang You-Yuan Huang Bo Wang 《Rare Metals》 2025年第4期2868-2868,共1页
In the original publication,incorrect version of Corresponding authors has been published.You-Yuan Huang and Bo Wang should be corresponding authors.The corrected Correspondingg authors are provided in this correction.
关键词 bo wang corrected correspondingg authors H BO Li reactive coating enhanced cycling stability single crystal LiNi Co Mn O
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110,000 ultralong cycling lithium-ion battery enabled by highly crystalline 2D covalent organic framework
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作者 Tianyu Zheng Lei Gong +8 位作者 Xiya Yang Tingting Sun Zhixin Liu Qingmei Xu Zhi Wang Yuhui Wang Kang Wang Dongdong Qi Jianzhuang Jiang 《Journal of Energy Chemistry》 2025年第11期434-443,I0011,共11页
Lithium-ion batteries(LIBs)with high energy and power densities are extensively applied in various fields,such as portable electronic devices and electric vehicles.Compared with traditional inorganic electrode materia... Lithium-ion batteries(LIBs)with high energy and power densities are extensively applied in various fields,such as portable electronic devices and electric vehicles.Compared with traditional inorganic electrode materials,which confront the challenges of resource scarcity and restrained energy density,covalent organic frameworks(COFs)are attractive candidates as electrode materials for the next-generation LIBs.Herein,rational Schiff-base condensation of tetraphenyl-pphenylenediamine(TPPDA)and 5,12-bis(4-(5,5-dimethyl-1,3-dioxan-2-yl)phenyl)-5,12-dihydroquinolino[2,3-b]acridine-7,14-dione(QA-PCHO)yields a two-dimensional(2D)QT-COF as the cathode.2D QT-COF features a high crystalline nature with kgm topology and hierarchically micro-/meso-porous structure,which can strengthen the stability of the chemical structure and promote the fast Li^(+)diffusion under large current densities.These merits make the QT-COF cathode exhibit 110,000 ultralong cycling stability with~100%retention at 10,000 mA g^(-1)upon running for 150 days,exceeding all the thus far reported COF-based electrodes.Additionally,the combination of ex situ X-ray photoelectron spectroscopy,in-situ Raman investigation,and theoretical calculation exhaustively unveils the ion storage mechanism and the rationale underlying the exceptional property of QT-COF.The present result offers an advanced COF with enormous potential as organic electrodes for LIBs,hopefully solving the challenges of ultrahigh cycling stability with superb capacity preservation at high current densities. 展开更多
关键词 2D Covalent organic frameworks Highly crystalline Lithium-ion batteries Ultralong cycling stability Bipolar ion storage mechanism
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Amelioration of Mechanical Properties of Rolled Mg-4.5Al-2.5Zn Alloy by Cryogenic Cycling Treatment
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作者 Haoran Pang Liwei Lu +4 位作者 Gongji Yang Xiaojun Wang Wen Wang Hua Zhang Yujuan Wu 《Acta Metallurgica Sinica(English Letters)》 2025年第8期1436-1452,共17页
In this study,cryogenic cycling treatment was used to process the hot-rolled Mg-4.5Al-2.5Zn alloy sheets to research the influence on mechanical properties and microstructure.Optical microscopy,electron back-scatter d... In this study,cryogenic cycling treatment was used to process the hot-rolled Mg-4.5Al-2.5Zn alloy sheets to research the influence on mechanical properties and microstructure.Optical microscopy,electron back-scatter diffraction and transmission electron microscopy were applied to characterize the microstructures and analyze the mechanisms.The consequences indicate that the cryogenic cycling treatment has significantly influence on improving the mechanical properties.With the cycle of cryogenic cycling treatment increasing to 5 cycles,the sample processed by 3 cycles presents the highest ductility(~18.6%),while the 4-cycle one shows the highest strength(~311.8 MPa).The improvement can be attributed to fine grains,introduced high-density dislocation,9.8%-fraction low-angle grain boundaries(LAGBs),the precipitation of Mg17Al12 phase and the texture with the intensity of 17.5.Although the average grain sizes of the samples processed by cryogenic cycling treatment have no obvious difference,internal stress variations induced by cryogenic cycling treatment significantly influence LAGBs,the basal texture evolution,and the prismaticslip,pyramidal<c>slip and pyramidal<c+a>slip activation. 展开更多
关键词 Mg-4.5Al-2.5Zn alloy Cryogenic cycling treatment Microstructure Mechanical properties
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Combining optimized irrigation with reduced N fertilization increases wheat N use efficiency by increasing soil N cycling and plant N uptake
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作者 Zhenkun Cui Yu Shi +2 位作者 Zhenwen Yu Yongli Zhang Zhen Zhang 《The Crop Journal》 2025年第6期1908-1918,共11页
With the aim of maximizing nitrogen use efficiency(NUE)of wheat in the North China Plain by optimizing irrigation and nitrogen application,a field experiment with a split-plot design was conducted.The main plots were ... With the aim of maximizing nitrogen use efficiency(NUE)of wheat in the North China Plain by optimizing irrigation and nitrogen application,a field experiment with a split-plot design was conducted.The main plots were subjected to three irrigation levels:bringing soil water content in the 0–40 cm profile to 65%(I1),75%(I2)and 85%(I3)of field water capacity.The subplots were subjected to three nitrogen application rates:150(N150),210(N210)and 270(N270)kg N ha−1.Compared with the N270,N210 treatment enhanced grain yield,NUE,and net income by 4.5%,6.2%,and 5.8%,respectively(two-year averages).Additionally,it reduced soil nitrate reductase activity,the abundance of denitrification-related bacteria,and loss rate of fertilizer nitrogen by 12.9%,53.3%,and 16.3%,respectively.Compared with the N150,N210 treatment increased grain yield,grain nitrogen accumulation,and net income by 15.9%,14.2%,and 26.3%.Relative to I1 and I3,I2 treatment increased root length density in the 20–60 cm soil layer,uptake rate of fertilizer nitrogen,grain yield,and net income.Overall,the combination of irrigation to 75%of field capacity with nitrogen application at 210 kg N ha^(−1)increased wheat’s capacity for nitrogen uptake and remobilization and thereby grain nitrogen accumulation,and increased NUE by reducing nitrogen loss rate. 展开更多
关键词 Water and nitrogen management Plant nitrogen uptake Soil nitrogen cycling Nitrogen use efficiency The^(15)N fate
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Geochemical cycling,tectonic drivers and environmental impacts of CH_(4)-rich mud extrusions in subduction zones
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作者 Umair Khan Shiguo Wu +2 位作者 Majid Khan Jinwei Gao Junjin Chen 《Geoscience Frontiers》 2025年第3期165-182,共18页
Subduction zones are critical interfaces for lithospheric volatile fluxes,where complex tectonic and geochemical interactions facilitate the release of gases and fluids from deep-seated reservoirs within the Earth’s ... Subduction zones are critical interfaces for lithospheric volatile fluxes,where complex tectonic and geochemical interactions facilitate the release of gases and fluids from deep-seated reservoirs within the Earth’s crust.Mud volcanism,as a dynamic manifestation of these processes,contributes CH_(4)emissions that influence the global methane budget and impact marine ecosystems.Although∼2000 CH_(4)-rich mud extrusions have been documented in subduction zones globally,the geological origins and subduction-related geochemical and tectonic mechanisms driving these emissions remain poorly understood.This research examines the Makran subduction zone which hosts one of the world’s largest accretionary wedge and extensive CH_(4)-rich mud extrusions,as a model system.Integrated geochemical,geophysical,and geological observations reveal that thermogenic CH_(4)and clay-rich fluidized muds originate from deeply buried Himalayan turbidites(underthrusted sediments),driven by organic-rich sediment maturation and high fluid overpressure.Key tectonic features,including thrust faults,overburden pressure of wedge-top sediments,normal faults,brittle fractures,and seismicity,facilitate CH_(4)-rich mud extrusions into the hydrosphere and atmosphere.The extruded gases are predominantly CH_(4),with minor C_(2)H_(6),C_(3)H_(8),i-C_(4)H_(10),and n-C_(4)H_(10)while the mud breccia exhibits a chemical composition dominated by SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3),enriched with trace elements(Rb,Zr,and V)and clay minerals,quartz,and carbonates.Geochemical indicators suggest intense chemical weathering and mature sediments classifying the mud breccia as litharenite and sub-litharenite,indicative of deep burial and compaction.These findings model the evolution of CH_(4)-rich mud extrusions through three geological stages:(i)Eocene to Early Miocene pre-thermogenic formation of the CH_(4)-rich source,(ii)Middle Miocene to Pliocene syn-thermogenic CH_(4)and fluidized mud generation,and(iii)Pleistocene to Recent post-thermogenic CH_(4)-rich fluidized mud migration.These findings underscore the critical yet often overlooked role of subduction-related geochemical and tectonic processes in CH_(4)generation and emission,with significant implications for the global CH_(4)budget and marine ecosystems. 展开更多
关键词 CH_(4)Mud volcanoes Geochemical cycling Subduction zones
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Nitrogen-cycling processes under long-term compound heavy metal(loids)pressure around a gold mine:Stimulation of nitrite reduction 被引量:1
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作者 Xuesong Hu Xiaoxia Liu +1 位作者 Shuo Zhang Caihong Yu 《Journal of Environmental Sciences》 2025年第1期571-581,共11页
Mining and tailings deposition can cause serious heavy metal(loids)pollution to the surrounding soil environment.Soil microorganisms adapt their metabolism to such conditions,driving alterations in soil function.This ... Mining and tailings deposition can cause serious heavy metal(loids)pollution to the surrounding soil environment.Soil microorganisms adapt their metabolism to such conditions,driving alterations in soil function.This study aims to elucidate the response patterns of nitrogen-cycling microorganisms under long-term heavy metal(loids)exposure.The results showed that the diversity and abundance of nitrogen-cyclingmicroorganisms showed negative feedback to heavy metal(loids)concentrations.Denitrifying microorganisms were shown to be the dominant microorganisms with over 60%of relative abundance and a complex community structure including 27 phyla.Further,the key bacterial species in the denitrification process were calculated using a random forest model,where the top three key species(Pseudomonas stutzei,Sphingobium japonicum and Leifsonia rubra)were found to play a prominent role in nitrite reduction.Functional gene analysis and qPCR revealed that nirK,which is involved in nitrite reduction,significantly accumulated in the most metal-rich soil with the increase of absolute abundance of 63.86%.The experimental results confirmed that the activity of nitrite reductase(Nir)encoded by nirK in the soil was increased at high concentrations of heavy metal(loids).Partial least squares-path model identified three potential modes of nitrite reduction processes being stimulated by heavy metal(loids),the most prominent of which contributed to enhanced nirK abundance and soil Nir activity through positive stimulation of key species.The results provide new insights and preliminary evidence on the stimulation of nitrite reduction processes by heavy metal(loids). 展开更多
关键词 N cycle Nitrite reduction Nitrite reductase METAGENOME Key species
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Effect of vinylene carbonate as electrolyte additive on cycling performance of LiFePO_4/graphite cell at elevated temperature 被引量:4
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作者 宋海申 曹政 +3 位作者 张治安 赖延清 李劼 刘业翔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期723-728,共6页
Effects of film-forming additive on stability of electrode and cycling performance of LiFePO4/graphite cell at elevated temperature were studied. Two 18650 cells with and without VC additive were investigated by galva... Effects of film-forming additive on stability of electrode and cycling performance of LiFePO4/graphite cell at elevated temperature were studied. Two 18650 cells with and without VC additive were investigated by galvanostatic cycling, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and Raman spectroscopy. The results show that in the presence of VC additive, dissolution of Fe from LiFePO4 material is greatly depressed and stability of graphite structure is improved; the additive can not only reduce reaction of electrolyte on surface of LiFePO4 electrode but also suppress reduction of solvent and thickening of the solid electrolyte interface (SEI) layer on graphite surface. Electrolyte with VC is considered to be a good candidate for improving cycling performance of the LiFePOa/graphite cell at elevated temperature. 展开更多
关键词 LiFeP04 vinylene carbonate electrolyte additive cycling performance
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Effect of sintering temperature on cycling performance and rate performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 被引量:2
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作者 李向群 熊训辉 +1 位作者 王志兴 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期4023-4029,共7页
LiNi0.8Co0.1Mn0.1O2 powder was prepared by mixing LiOH·H2O and co-precipitated Ni0.8Co0.1Mn0.1(OH)2 at a molar ratio of 1:1.05, followed by sintering at different temperatures. The effects of temperature on th... LiNi0.8Co0.1Mn0.1O2 powder was prepared by mixing LiOH·H2O and co-precipitated Ni0.8Co0.1Mn0.1(OH)2 at a molar ratio of 1:1.05, followed by sintering at different temperatures. The effects of temperature on the morphology, structure and electrochemical performance were extensively studied. SEM and XRD results demonstrate that the sintering temperature has large influence on the morphology and structure and suitable temperature is very important to obtain spherical materials and suppresses the ionic distribution. The charge-discharge tests show that the electrochemical performance of LiNi0.8Co0.1Mn0.1O2 powders becomes better with the increase of temperature from 700 ℃ to 750 ℃ and higher temperature will deteriorate the performance. Although both of materials obtained at 750 ℃ and 780 ℃ demonstrate almost identical cyclic stability at 2C rate, which delivers 71.9%retention after 200 cycles, the rate performance of powder calcined at 780 ℃ is much poorer than that at 750 ℃. The XRD results demonstrate that the poor performance is ascribed to more severe ionic distribution caused by higher temperature. 展开更多
关键词 lithium ion battery LiNi0.8CO0.1Mn0.1O2 sintering temperature cycling performance rate performance
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布鲁菌Cycling探针荧光定量PCR检测方法的建立 被引量:2
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作者 许邹亮 南文龙 +4 位作者 陆明哲 周洁 谭鹏飞 陈义平 毛开荣 《中国兽医杂志》 CAS 北大核心 2012年第2期13-16,共4页
根据布鲁菌BCSP31基因序列设计布鲁菌通用检测引物和探针,建立了布鲁菌Cycling探针荧光定量PCR检测方法。以构建的含BCSP31基因的质粒标准品10倍递进稀释为模板检测其敏感性,结果显示,本方法能检测约10个拷贝的阳性质粒,且标准曲线的线... 根据布鲁菌BCSP31基因序列设计布鲁菌通用检测引物和探针,建立了布鲁菌Cycling探针荧光定量PCR检测方法。以构建的含BCSP31基因的质粒标准品10倍递进稀释为模板检测其敏感性,结果显示,本方法能检测约10个拷贝的阳性质粒,且标准曲线的线性关系良好。用本方法检测5株不同种的布鲁菌以及猪大肠杆菌K99、巴氏杆菌C48-1、猪链球菌ST171、绿脓杆菌等4株对照菌。结果显示,5株不同种的布鲁菌均出现典型的"S"型扩增曲线,4株对照菌40个循环内均无CT值出现。用本方法和B4/B5-PCR方法对来自布鲁菌病流行地区3个不同牛场的40份血样、奶样和血清样进行平行检测。结果显示,本方法和B4/B5-PCR方法的结果符合率为80.0%。B4/B5-PCR检测为阳性的27份样品经本方法检测均为阳性;B4/B5-PCR检测为阴性的13份样本,经本方法检测,其中8份呈阳性,5份为阴性。本方法的敏感性明显高于B4/B5-PCR方法。试验表明,所建立的Cycling探针荧光定量PCR方法具有敏感、特异、稳定等特点,可用于布鲁菌感染的快速检测。 展开更多
关键词 布鲁菌 cycling探针荧光定量PCR
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Impact of Duty Cycling HVAC Systems on Thermal Comfort,Energy Consumption,and Operational Costs
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作者 Alya Penta Agharid Indra Permana +2 位作者 Linlan Chang Yi-Han Luo Fujen Wang 《Energy Engineering》 2025年第9期3839-3866,共28页
Air conditioning(AC)is essential for maintaining indoor comfort during Taiwan region’s hot and humid summers but significantly contributes to increased energy consumption.This study evaluates the effects of AC dutycy... Air conditioning(AC)is essential for maintaining indoor comfort during Taiwan region’s hot and humid summers but significantly contributes to increased energy consumption.This study evaluates the effects of AC dutycycling strategies on energy performance,thermal comfort,and operational costs in office environments.Duty-cycling was implemented using a building energy management system(BEMS),which remotely controlled the ON/OFF cycles of AC units.Five duty-cycling modes were tested,with some modes incorporating air circulation during OFF periods.Field measurements of energy consumption,temperature,humidity,and air velocity were conducted and integrated with thermal comfort analysis tools to calculate predictedmean vote(PMV)and percentage of dissatisfied(PPD)values.The objective was to achieve energy savings while maintaining acceptable thermal comfort levels.Results show that Mode A achieved the highest energy savings,reducing monthly consumption by 40.79%;however,it slightly exceeded the PMV threshold(+0.5)and recorded a PPD greater than 10%,indicating reduced occupant comfort.In contrast,Mode C provided a better balance,achieving a 27.61%reduction in energy consumption while maintaining a PMV of+0.28 and a PPD of 7.49%,both within acceptable comfort limits.Despite the energy-saving benefits,not all dutycycling modes ensured satisfactory thermal comfort.Additionally,the cost analysis revealed thatMode A achieved the lowest monthly electricity cost(NTD 8476.18/USD 263.38),whileMode C incurred a higher cost(NTD 10,363.00/USD 322.01),highlighting the trade-off between energy savings,comfort,and economic impact. 展开更多
关键词 Air conditioning duty cycle ENERGY-SAVING thermal comfort field measurement
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