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In-situ construction of high-mechanical-strength and fast-ion-conductivity interphase for anode-free Li battery 被引量:1
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作者 Yangfan Lin Juner Chen +1 位作者 han zhang Jianhui Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期207-214,I0006,共9页
The solid electrolyte interphase(SEI)with strong mechanical strength and high ion conductivity is highly desired for Li metal batteries,especially for harsh anode-free batteries.Herein,we report a pragmatic approach t... The solid electrolyte interphase(SEI)with strong mechanical strength and high ion conductivity is highly desired for Li metal batteries,especially for harsh anode-free batteries.Herein,we report a pragmatic approach to the in-situ construction of high-quality SEI by applying synergistic additives of Li NO_(3)and ethylene sulfite(ES)in the electrolyte.The obtained SEI exhibits a high average Young’s modulus(9.02GPa)and exchanging current density(4.59 mA cm^(-2)),which are 3.0 and 1.2 times as large as those using the sole additive of LiNO_(3),respectively.With this improved SEI,Li-dendrite growth and side reactions are effectively suppressed,leading to an ultra-high Coulombic efficiency(CE)of 99.7%for Li plating and stripping.When applying this improved electrolyte in full cells,it achieves a high capacity retention of 89.7%for over 150 cycles in a LiFePO_(4)||Li battery(~12 mg cm^(-2)cathode,50μm Li)and of 44.5%over 100 cycles in a LiFePO_(4)||Cu anode-free battery. 展开更多
关键词 Anode-free Li battery Solid electrolyte interphase ADDITIVE Lithiu mnitrate Ethylene sulfite
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云南个旧锡多金属矿集区电气石地球化学组成和硼同位素特征——对成矿流体性质和演化的约束
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作者 任竑宇 李超 +4 位作者 江小均 杨富成 韩嶂 芦磊 陈耀坤 《地球学报》 CAS CSCD 北大核心 2024年第4期575-590,共16页
个旧锡矿集区发育与晚白垩世高分异花岗岩有关的世界级Sn-Cu多金属矿床,其成矿物质的来源及流体演化过程一直是研究的热点和难点。个旧地区电气石广泛发育于碳酸盐岩、花岗岩及矽卡岩中,但对电气石尚未进行系统研究,电气石与成矿之间的... 个旧锡矿集区发育与晚白垩世高分异花岗岩有关的世界级Sn-Cu多金属矿床,其成矿物质的来源及流体演化过程一直是研究的热点和难点。个旧地区电气石广泛发育于碳酸盐岩、花岗岩及矽卡岩中,但对电气石尚未进行系统研究,电气石与成矿之间的关系尚未明确。本文对不同类型电气石开展了系统的岩相学观察和电子探针(EPMA)、LA-ICP-MS微量元素和硼同位素分析。结果表明,所有电气石都属于碱性电气石,TurⅠ、TurⅡ、TurⅣ为热液成因,TurⅢ为岩浆成因。岩浆电气石相比于热液电气石具有更低的Mg、Ca等元素,TurⅠ电气石高含量的Sr表明受到了围岩的混染。电气石的微量元素变化表明,从似斑状花岗岩到等粒花岗岩,随着岩浆分异程度逐渐增加,Sn在岩浆中逐渐富集,在似斑状花岗岩和接触带矽卡岩中沉淀卸载。个旧不同类型电气石具有均一的δ11B值(−15.2‰~−12.8‰),与花岗岩的组成范围一致,表明成矿物质来源均来源于花岗质岩浆。 展开更多
关键词 电气石 硼同位素 岩浆-热液型锡多金属矿床 个旧锡矿矿集区
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Genetically modified non-human primate models for research on neurodegenerative diseases 被引量:1
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作者 Ming-Tian Pan han zhang +1 位作者 Xiao-Jiang Li Xiang-Yu Guo 《Zoological Research》 SCIE CSCD 2024年第2期263-274,共12页
Neurodegenerative diseases(NDs)are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease(AD),Parkinson's disease(PD),Huntington's disease(... Neurodegenerative diseases(NDs)are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease(AD),Parkinson's disease(PD),Huntington's disease(HD),and amyotrophic lateral sclerosis(ALS).Currently,there are no therapies available that can delay,stop,or reverse the pathological progression of NDs in clinical settings.As the population ages,NDs are imposing a huge burden on public health systems and affected families.Animal models are important tools for preclinical investigations to understand disease pathogenesis and test potential treatments.While numerous rodent models of NDs have been developed to enhance our understanding of disease mechanisms,the limited success of translating findings from animal models to clinical practice suggests that there is still a need to bridge this translation gap.Old World nonhuman primates(NHPs),such as rhesus,cynomolgus,and vervet monkeys,are phylogenetically,physiologically,biochemically,and behaviorally most relevant to humans.This is particularly evident in the similarity of the structure and function of their central nervous systems,rendering such species uniquely valuable for neuroscience research.Recently,the development of several genetically modified NHP models of NDs has successfully recapitulated key pathologies and revealed novel mechanisms.This review focuses on the efficacy of NHPs in modeling NDs and the novel pathological insights gained,as well as the challenges associated with the generation of such models and the complexities involved in their subsequent analysis. 展开更多
关键词 NEURODEGENERATION Non-human primate Macaque monkey Animal model Gene modification
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变速抽水蓄能机组调速系统的自适应反步控制
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作者 韩璋 马润 +4 位作者 姜福超 丁号月 赵庆杞 张越 邢作霞 《实验技术与管理》 CAS 北大核心 2024年第5期121-126,共6页
针对变速抽水蓄能机组最优目标转速时常随目标功率的改变而变化的特点,设计了一种带指令滤波的自适应反步控制器。构造了变速机组调速系统的数学模型,根据转速寻优方法建立最优转速模块,并以此为基础设计了对电磁功率进行自适应估计的... 针对变速抽水蓄能机组最优目标转速时常随目标功率的改变而变化的特点,设计了一种带指令滤波的自适应反步控制器。构造了变速机组调速系统的数学模型,根据转速寻优方法建立最优转速模块,并以此为基础设计了对电磁功率进行自适应估计的自适应反步控制器。为了克服反步控制中存在的计算膨胀问题,引入了指令滤波,通过仿真模拟实验来检验反步控制在不同负荷工况下的控制效果。仿真结果表明,在各种负荷工况下,所设计的调速控制器能够使系统实际转速很好地跟踪所需的最优转速,证明了所设计的调速控制器的有效性。学生可通过替换最优转速模块,分析自主设计的控制器的稳定性,更加直观地学习控制理论与调速系统的联系。 展开更多
关键词 变速抽水蓄能 反步法 指令滤波
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The influence of inter-band rock on rib spalling in longwall panel with large mining height
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作者 Jiachen Wang Meng Li +3 位作者 Zhaohui Wang Zheng Li han zhang Shixiong Song 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期427-442,共16页
In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by con... In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by considering the rock layer.A safety factor is defined foy the rib,and it is observed that the safety factor exhibits a positive correlation with the thickness and strength of the inter-band rock.A calculation method for determining critical parameters of the rock layer is presented to ensure the rib stability.It is revealed that incomplete propagation of the fracture at the hard rock constitutes a fundamental prerequisite for ensuring the rib stability.The influence of the position of the inter-band rock in the coal seam on failure mechanism of the rib was thoroughly investigated by developing a series of physical models for the rib at the face area.The best position for the inter-band rock in the coal seam is at a height of 1.5 m away from the roof line,which tends to provide a good stability state for the rib.For different inter-band rock positions,two ways of controlling rib by increasing supports stiffness and flexible grouting reinforcement are proposed. 展开更多
关键词 Rib spalling Inter-band rock Large mining height Limit analysis Physical model experiment Numerical simulation
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High donor-number and low content electrolyte additive for stabilizing zinc metal anode
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作者 Yuxin Gong Ruifan Lin +9 位作者 Bo Wang Huaizheng Ren Lei Wang han zhang Jianxin Wang Deyu Li Yueping Xiong Dianlong Wang Huakun Liu Shixue Dou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期626-635,I0014,共11页
The aqueous zinc ion batteries(AZIBs)are thought as promising competitors for electrochemical energy storage,though their wide application is curbed by the uncontrollable dendrite growth and gas evolution side reactio... The aqueous zinc ion batteries(AZIBs)are thought as promising competitors for electrochemical energy storage,though their wide application is curbed by the uncontrollable dendrite growth and gas evolution side reactions.Herein,to stabilize both zinc anodes and water molecules,we developed a modified electrolyte by adding a trace amount of N,N-diethylformanmide(DEF)into the ZnSO_(4)electrolyte for the first time in zinc ion batteries.The effectiveness of DEF is predicted by the comparison of donor number and its preferential adsorption behavior on the zinc anode is further demonstrated by several spectroscopy characterizations,electrochemical methods,and molecular dynamics simulation.The modified electrolyte with 5%v.t.DEF content can ensure a stable cycling life longer than 3400 h of Zn‖Zn symmetric cells and an ultra-reversible Zn stripping/plating process with a high coulombic efficiency of 99.7%.The Zn‖VO_(2)full cell maintains a capacity retention of 83.5%and a 104 mA h g^(-1)mass capacity after 1000cycles.This work provides insights into the role of interfacial adsorption behavior and the donor number of additive molecules in designing low-content and effective aqueous electrolytes. 展开更多
关键词 Aqueous zinc ion batteries Zinc anode Electrolyte additives Donor number Zinc dendrites
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The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function
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作者 Qiao Li Jianying Guo +1 位作者 han zhang Mengxin Zhao 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期267-282,共16页
Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important ro... Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correlation analyses verified that these genera had significantly positive relationships with soil nutrients and enzyme activities.Plant biomass,soil p H,and the contents of organic matter,TN,NO_(3)^(-),TP,AP,TK,and AK were the main factors affecting soil microbial communities.This study showed that the invasion of B.pilosa led to significant alterations in the composition of the soil microbial communities.These changes were closely linked to modifications in plant traits as well as soil physical and chemical properties.Some microbial species related to C,N and P cycling were enriched in the soil invaded by B.pilosa.These findings provide additional support for the hypothesis of soil-microbe feedback in the successful invasion of alien plants.They also offer insights into the ecological mechanism by which soil microbes contribute to the successful invasion of B.pilosa.Overall,our research contributes to a better understanding of the complex interactions between invasive plants,soil microbial communities,and ecosystem dynamics. 展开更多
关键词 plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities
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Loosely coordinating diluted highly concentrated electrolyte toward -60℃ Li metal batteries
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作者 han zhang Ziqi Zeng +5 位作者 Qiang Wu Xinlan Wang Mingsheng Qin Sheng Lei Shijie Cheng Jia Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期380-387,I0009,共9页
Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferio... Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs. 展开更多
关键词 Lithium metal batteries -60℃operation Lithium metal anode compatibility Li^(+) desolvation kinetics
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Reversible Optical Isolators and Quasi-Circulators Using a Magneto-Optical Fabry-Pérot Cavity
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作者 张天天 周文鹏 +7 位作者 李志向 唐宇涛 许帆 吴浩东 张涵 唐江山 阮亚平 夏可宇 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期59-68,共10页
Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonrecip... Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonreciprocal devices rely on a strong magnetic field,which is provided by a permanent magnet.As a result,the isolation direction of such devices is fixed and severely restricts their applications in quantum networks.In this work,we experimentally demonstrate the simultaneous one-way transmission and unidirectional reflection by using a magneto-optical Fabry-Pérot cavity and a magnetic field strength of 50 mT.An optical isolator and a three-port quasi-circulator are realized based on this nonreciprocal cavity system.The isolator achieves an isolation ratio of up to 22 dB and an averaged insertion loss down to 0.97 dB.The quasi-circulator is realized with a fidelity exceeding 99% and an overall survival probability of 89.9%,corresponding to an insertion loss of~0.46 dB.The magnetic field is provided by an electromagnetic coil,thereby allowing for reversing the light circulating path.The reversible quasi-circulator paves the way for building reconfigurable quantum networks. 展开更多
关键词 quantum reciprocal INSERTION
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Debt,sleep deprivation and psychological distress among online ride-hailing drivers:evidence from China
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作者 Wanjie Tang Jingyue Chen +9 位作者 Simiao Wang Xianglan Jiang Yi Lu Siqi Wu Luyu Yang Meng Tian han zhang Yinan zhang Jiuping Xu Zeyuan Sun 《General Psychiatry》 CSCD 2024年第2期319-323,共5页
An online ride-hailing driver(ORHD)refers to a driver who takes orders and provides rental car services to passengers via an online service platform.1 ORHD plays a significant role in the urban transport system worldw... An online ride-hailing driver(ORHD)refers to a driver who takes orders and provides rental car services to passengers via an online service platform.1 ORHD plays a significant role in the urban transport system worldwide,operating through many platforms.According to official data from the Chinese Ministry of Transport,a total of 1.6 million vehicle transport permits were issued by the end of March 2022. 展开更多
关键词 services service OFFICIAL
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Effect of Trace Addition of Ceramic on Microstructure Development and Mechanical Properties of Selective Laser Melted AlSi10Mg Alloy 被引量:7
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作者 Yuxin Li Dongdong Gu +1 位作者 han zhang Lixia Xi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第2期56-68,共13页
Selective laser melting(SLM)is an emerging additive manufacturing technology for fabricating aluminum alloys and aluminum matrix composites.Nevertheless,it remains unclear how to improve the properties of laser manufa... Selective laser melting(SLM)is an emerging additive manufacturing technology for fabricating aluminum alloys and aluminum matrix composites.Nevertheless,it remains unclear how to improve the properties of laser manufactured aluminum alloy by adding ceramic reinforcing particles.Here the effect of trace addition of TiB2 ceramic(1%weight fraction)on microstructural and mechanical properties of SLM-produced AlSi10Mg composite parts was investigated.The densification level increased with increasing laser power and decreasing scan speed.A near fully dense composite part(99.37%)with smooth surface morphology and elevated inter-layer bonding was successfully obtained.A decrease of lattice plane distance was identified by X-ray diffraction with the laser scan speed decreased,which implied that the crystal lattices were distorted due to the dissolution of Si and TiB2 particles.A homogeneous composite microstructure with the distribution of surface-smoothened TiB2 particles was present,and a small amount of Si particles precipitated at the interface between reinforcing particles and matrix.In contrast to the AlSi10Mg alloy,the composites showed a stabilized microhardness distribution.A higher ultimate tensile strength of 380.0 MPa,yield strength of 250.4 MPa and elongation of 3.43%were obtained even with a trace amount of ceramic addition.The improvement of tensile properties can be attributed to multiple mechanisms including solid solution strengthening,load-bearing strengthening and dispersion strengthening.This research provides a theoretical basis for ceramic reinforced aluminum matrix composites by additive manufacturing. 展开更多
关键词 Selective laser melting TIB2 Aluminum matrix composites Mechanical properties Strengthening mechanism
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Role of laser scan strategies in defect control,microstructural evolution and mechanical properties of steel matrix composites prepared by laser additive manufacturing 被引量:4
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作者 Hong-yu Chen Dong-dong Gu +5 位作者 Qing Ge Xin-yu Shi Hong-mei zhang Rui Wang han zhang Konrad Kosiba 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第3期462-474,共13页
Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,... Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,microstructural evolution,and mechanical properties of SMCs was established.The laser scan strategies can be manipulated to deliberately alter the thermal history of SMC during SLM processing.Particularly,the involved thermal cycling,which encompassed multiple layers,strongly affected the processing quality of SMCs.Sshaped scan sequence combined with interlayer offset and orthogonal stagger mode can effectively eliminate the metallurgical defects and retained austenite within the produced SMCs.However,due to large thermal stress,microcracks that were perpendicular to the building direction formed within the SMCs.By employing the checkerboard filling(CBF)hatching mode,the thermal stress arising during SLM can be significantly reduced,thus preventing the evolution of interlayer microcracks.The compressive properties of fabricated SMCs can be tailored at a high compressive strength(~3031.5 MPa)and fracture strain(~24.8%)by adopting the CBF hatching mode combined with the optimized scan sequence and stagger mode.This study demonstrates great feasibility in tuning the mechanical properties of SLM-fabricated SMCs without varying the set energy input,e.g.,laser power and scanning speed. 展开更多
关键词 laser additive manufacturing selective laser melting scan strategy defect control mechanical property
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Conformance control by a microgel in a multi-layered heterogeneous reservoir during CO_(2) enhanced oil recovery process 被引量:2
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作者 Zheyu Liu Jian zhang +6 位作者 Xianjie Li Chunming Xu Xin Chen Bo zhang Guang Zhao han zhang Yiqiang Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期324-334,共11页
Injecting CO_(2)into the underground for oil displacement and shortage is an important technique for carbon capture,utilization and storage(CCUS).One of the main problems during the CO_(2)injection is the channeling p... Injecting CO_(2)into the underground for oil displacement and shortage is an important technique for carbon capture,utilization and storage(CCUS).One of the main problems during the CO_(2)injection is the channeling plugging.Finding an effective method for the gas channeling plugging is a critical issue in the CO_(2)EOR process.In this work,an acid-resistance microgel named dispersed particle gel(DPG)was characterized and its stability was tested in the CO_(2)environment.The microgel size selection strategies for the homogeneous and heterogeneous reservoirs were respectively investigated using the single core flooding and three parallel core flooding experiments.Moreover,the comparison of microgel alternate CO_(2)(MAC)injection and water alternate CO_(2)(WAC)injection in the dual core flooding experiments were presented for the investigation of the role of microgel on the conformance control in CO_(2)flooding process.The results have shown that the microgel featured with ANH and CAN groups can keep its morphology after aging 7 days in the CO_(2)environment.Where,the small microgel with unobstructed migration and large microgel with good plugging efficiency for the high permeability zone were respectively featured with the higher recovery factor in homogeneous and heterogeneous conditions,which indicate they are preferred used for the oil displacement and conformance control.Compared to WAC injection,MAC injection had a higher incremental recovery factor of 12.4%.It suggests the acid-resistance microgel would be a good candidate for the conformance control during CO_(2)flooding process. 展开更多
关键词 Carbon dioxide Microgels Enhanced oil recovery Conformance control Porous media
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Effects of dissolved oxygen and nutrients from the Kuroshio on hypoxia off the Changjiang River estuary 被引量:1
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作者 Di TIAN Feng ZHOU +3 位作者 Wenyan zhang han zhang Xiao MA Xinyu GUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第2期515-529,共15页
The intrusion of the Kuroshio into the East China Sea(ECS)aff ects the development of hypoxia off the Changjiang(Yangtze)River estuary;however,quantitative analysis of its impacts is lacking.In this study,the Regional... The intrusion of the Kuroshio into the East China Sea(ECS)aff ects the development of hypoxia off the Changjiang(Yangtze)River estuary;however,quantitative analysis of its impacts is lacking.In this study,the Regional Ocean Modeling Systems(ROMS)model coupled with the Carbon,Silicate and Nitrogen Ecosystem(CoSiNE)model was used to investigate the relative importance of dissolved oxygen(DO)and diff erent nutrients(silicate,nitrate,and phosphate)in the Kuroshio on hypoxia in the ECS.Results show that changes in DO concentrations in the Kuroshio modify the distribution and intensity of hypoxia through direct onshore transport by hydrodynamic processes.An increase in Kuroshio DO concentration by 25%or 50%would result in a decrease of the maximum hypoxia extent(MHE)in the ECS by 76%or 86%,respectively,while a 25%decrease in Kuroshio DO would increase the MHE by up to 219%.The contribution of DO in the Taiwan Strait is almost negligible.In contrast to Kuroshio DO,nutrients aff ect hypoxia in the ECS through onshore transport by hydrodynamic and biochemical processes.Changes in phosphate and nitrate concentrations by 25%in the Kuroshio would change the MHE by up to 30%and 18%,respectively,accompanied by apparent changes in surface chlorophyll-a concentrations.The eff ect of silicate on hypoxia is negligible because a 25%change in silicate concentrations in the Kuroshio would result in less than 1%change in the MHE.Our results reveal a hierarchical rank of importance for environmental variables in the Kuroshio(i.e.,DO>phosphate>nitrate>silicate)in modifying the development of hypoxia in the ECS. 展开更多
关键词 HYPOXIA KUROSHIO Changjiang River estuary East China Sea dissolved oxygen NUTRIENT
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Change and impact of left ventricular global longitudinal strain during transcatheter aortic valve implantation 被引量:1
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作者 han zhang Jin-Jie Xie +5 位作者 Rong-Juan Li Yue-Li Wang Bao-Rong Niu Li Song Jing Li Ya Yang 《World Journal of Clinical Cases》 SCIE 2022年第6期1806-1814,共9页
BACKGROUND Although transcatheter aortic valve implantation(TAVI)is a safe and effective treatment for aortic stenosis,it still carries some risks,such as valve leaks,stroke,and even death.The left ventricular global ... BACKGROUND Although transcatheter aortic valve implantation(TAVI)is a safe and effective treatment for aortic stenosis,it still carries some risks,such as valve leaks,stroke,and even death.The left ventricular global longitudinal strain(LVGLS)measurement may be useful for the prediction of adverse events during this operation.AIM To explore the change of LVGLS during TAVI procedure and the relationship between LVGLS and perioperative adverse events.METHODS In this study,61 patients who had undergone percutaneous transfemoral TAVI were evaluated by transthoracic echocardiography.Before surgery,data on left ventricular ejection fraction(LVEF)and LVGLS were collected separately following balloon expansion and stent implantation.Difference in values of LVGLS and LVEF during preoperative balloon expansion(pre-ex),preoperative stent implantation(pre-im)and balloon expansion-stent implantation(ex-im)were also examined.Adverse events were defined as perioperative death,cardiac rupture,heart arrest,moderate or severe perivalvular leakage,significant mitral regurgitation during TAVI,perioperative moderate or severe mitral regurgitation,perioperative left ventricular outflow tract obstruction,reoperation,and acute heart failure.RESULTS The occurrence of perioperative adverse events was associated with differences in pre-ex LVGLS,but not with difference in pre-ex LVEF.There were significant differences between pre-LVGLS and ex-LVGLS,and between pre-LVGLS and im-LVGLS(P=0.037 and P=0.020,respectively).However,differences in LVEF were not significant(P=0.358,P=0.254);however differences in pre-ex LVGLS were associated with pre-LVGLS(P=0.045).Compared to LVEF,LVGLS is more sensitive as a measure of left heart function during TAVI and the perioperative period.Moreover,the differences in LVGLS were associated with the occurrence of perioperative adverse events,and changes in LVGLS were apparent in patients with undesirable LVGLS before the surgery.Furthermore,LVGLS is useful to predict changes in cardiac function during TAVI.CONCLUSION Greater attention should be paid to the patients who plan to undergo TAVI with normal LVEF but poor LVGLS. 展开更多
关键词 Aortic stenosis Ejection fraction Longitudinal strain Transcatheter aortic valve implantation Left ventricular global longitudinal strain
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High-resolution Simulation of an Extreme Heavy Rainfall Event in Shanghai Using the Weather Research and Forecasting Model: Sensitivity to Planetary Boundary Layer Parameterization 被引量:1
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作者 Rui WANG Yiting ZHU +3 位作者 Fengxue QIAO Xin-Zhong LIANG han zhang Yang DING 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第1期98-115,共18页
In this study,an extreme rainfall event that occurred on 25 May 2018 over Shanghai and its nearby area was simulated using the Weather Research and Forecasting model,with a focus on the effects of planetary boundary l... In this study,an extreme rainfall event that occurred on 25 May 2018 over Shanghai and its nearby area was simulated using the Weather Research and Forecasting model,with a focus on the effects of planetary boundary layer(PBL)physics using double nesting with large grid ratios(15:1 and 9:1).The sensitivity of the precipitation forecast was examined through three PBL schemes:the Yonsei University Scheme,the Mellor−Yamada−Nakanishi Niino Level 2.5(MYNN)scheme,and the Mellor−Yamada−Janjic scheme.The PBL effects on boundary layer structures,convective thermodynamic and large-scale forcings were investigated to explain the model differences in extreme rainfall distributions and hourly variations.The results indicated that in single coarser grids(15 km and 9 km),the extreme rainfall amount was largely underestimated with all three PBL schemes.In the inner 1-km grid,the underestimated intensity was improved;however,using the MYNN scheme for the 1-km grid domain with explicitly resolved convection and nested within the 9-km grid using the Kain−Fritsch cumulus scheme,significant advantages over the other PBL schemes are revealed in predicting the extreme rainfall distribution and the time of primary peak rainfall.MYNN,with the weakest vertical mixing,produced the shallowest and most humid inversion layer with the lowest lifting condensation level,but stronger wind fields and upward motions from the top of the boundary layer to upper levels.These factors all facilitate the development of deep convection and moisture transport for intense precipitation,and result in its most realistic prediction of the primary rainfall peak. 展开更多
关键词 PBL parameterization extreme rainfall high resolution
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Small Sample Gear Fault Diagnosis Method Based on Transfer Learning
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作者 han zhang Shihao Liu +1 位作者 Xiyang Wang Junlong zhang 《Open Journal of Applied Sciences》 2023年第12期2461-2479,共19页
Aiming at the problems of lack of fault diagnosis samples and low model generalization ability of cross-working gear based on deep transfer learning, a fault diagnosis method based on improved deep residual network an... Aiming at the problems of lack of fault diagnosis samples and low model generalization ability of cross-working gear based on deep transfer learning, a fault diagnosis method based on improved deep residual network and transfer learning was proposed. Firstly, one-dimensional signal is transformed into two-dimensional time-frequency image by continuous wavelet transform. Then, a deep learning model based on ResNet50 is constructed. Attention mechanism is introduced into the model to make the model pay more attention to the useful features for the current task. The network parameters trained by ResNet50 network on ImageNet dataset were used to initialize the model and applied to the fault diagnosis field. Finally, to solve the problem of gear fault diagnosis under different working conditions, a small sample training set is proposed for fault diagnosis. The method is applied to gearbox fault diagnosis, and the results show that: The proposed deep model achieves 99.7% accuracy of gear fault diagnosis, which is better than the four models such as VGG19 and MobileNetV2. In the cross-working condition fault diagnosis, only 20% target dataset is used as the training set, and the proposed method achieves 93.5% accuracy. 展开更多
关键词 Gear Fault Diagnosis Transfer Learning CWT Deep Residual Network Deep Learning
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Responsive mechanism and coordination mode effect of a bipyridine-based two-photon fluorescent probe for zinc ion
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作者 张瀚 邵哲 赵珂 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期243-249,共7页
The properties of one-photon absorption(OPA),emission and two-photon absorption(TPA)of a bipyridine-based zinc ion probe are investigated employing the density functional theory in combination with response functions.... The properties of one-photon absorption(OPA),emission and two-photon absorption(TPA)of a bipyridine-based zinc ion probe are investigated employing the density functional theory in combination with response functions.The responsive mechanism and coordination mode effect are explored.The structural fluctuation is illustrated by molecular dynamics simulation.The calculated OPA and emission wavelengths of the probe are consistent with the experimental data.It is found that the red-shift of OPA wavelength and the enhancement of TPA intensity are induced by the increased intra-molecular charge transfer mechanism upon metal binding.The structural fluctuation could result in the blue-shift of TPA wavelength and the decrease of the TPA cross section.The TPA properties are quite different among the zinc complexes with different coordination modes.The TPA wavelength of the complexes with two ligands is close to that of the probe,which is in agreement with the experimental observation. 展开更多
关键词 two-photon absorption fluorescent probe zinc ion coordination mode BIPYRIDINE
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Amplified Detection of Iron Ion Based on Plasmon Enhanced Fluorescence and Subsequently Fluorescence Quenching
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作者 Lin Zhou han zhang +2 位作者 Yanping Luan Si Cheng Li-Juan Fan 《Nano-Micro Letters》 SCIE EI CAS 2014年第4期327-334,共8页
A facile and rapid approach for detecting low concentration of iron ion(Fe3+) with improved sensitivity was developed on the basis of plasmon enhanced fluorescence and subsequently amplified fluorescence quenching.Au1... A facile and rapid approach for detecting low concentration of iron ion(Fe3+) with improved sensitivity was developed on the basis of plasmon enhanced fluorescence and subsequently amplified fluorescence quenching.Au1Ag4@Si O2 nanoparticles were synthesized and dispersed into fluorescein isothiocyanate(FITC) solution. The fluorescence of the FITC solution was improved due to plasmon enhanced fluorescence. However, efficient fluorescence quenching of the FITC/Au1Ag4@Si O2 solution was subsequently achieved when Fe3+, with a concentration ranging from17 n M to 3.4 l M, was added into the FITC/Au1Ag4@Si O2 solution, whereas almost no fluorescence quenching was observed for pure FITC solution under the same condition. FITC/Au1Ag4@Si O2 solution shows a better sensitivity for detecting low concentration of Fe3+compared to pure FITC solution. The quantized limit of detection toward Fe3+was improved from 4.6 l M for pure FITC solution to 20 n M for FITC/Au1Ag4@Si O2 solution. 展开更多
关键词 Gold–silver alloy Plasmon enhanced fluorescence Fluorescence quenching Iron ion
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Enhanced Succinic Acid Production from Sake Lees Hydrolysate by Dilute Sulfuric Acid Pretreatment and Biotin Supplementation
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作者 Ke-Quan Chen han zhang +2 位作者 Ye-Lian Miao Min Jiang Jie-Yu Chen 《Journal of Sustainable Bioenergy Systems》 2012年第2期19-25,共7页
Succinic acid is valued as a potential starting point for the production of chemicals of the C4 family or in the prepara-tion of biodegradable polymers. For sustainable development in this era of petroleum shortage, p... Succinic acid is valued as a potential starting point for the production of chemicals of the C4 family or in the prepara-tion of biodegradable polymers. For sustainable development in this era of petroleum shortage, production of succinic acid by microbial fermentation of renewable feedstock has attracted great interest. In this study, pretreatment with sulfuric acid and biotin supplementation were used to enhance succinic acid production by Actinobacillus succinogenes 130Z from sake lees, a byproduct of Japanese rice wine. Pretreatment with sulfuric acid resulted in little change of glucose, total nitrogen and succinic acid content in the sake lees hydrolysate but had a positive effect on succinic acid fermentation, which caused a 25.0% increase in succinic acid yield in batch fermentation. Biotin supplementation was used to further enhance the fermentability of sake lees hydrolysate. As a result, a 30 h batch fermentation of 0.5% sulfuric acid pretreated sake lees hydrolysate with 0.2 mg/L biotin gave a succinic acid yield of 0.59 g/g from 61.6 g/L of glucose, with a productivity of 1.21 g/(L?h). A 22.9% increase in succinic acid yield and a 101.7% increase in succinic acid productivity were obtained compared with untreated sake lees hydrolysate. 展开更多
关键词 Succinic ACID A. Succinogenes Sake LEES HYDROLYSATE PRETREATMENT BIOTIN
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