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Atom substitution of the solid-state electrolyte Li_(10)GeP_(2)S_(12)for stabilized all-solid-state lithium metal batteries 被引量:1
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作者 Zijing Wan Xiaozhen Chen +3 位作者 Ziqi Zhou Xiaoliang Zhong Xiaobing Luo Dongwei Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期28-38,I0002,共12页
Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical applicati... Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical application.Among all solutions,Ge atom substitution of the solid-state electrolyte LGPS stands out as the most promising solution to this interface problem.A systematic screening framework for Ge atom substitution including ionic conductivity,thermodynamic stability,electronic and mechanical properties is utilized to solve it.For fast screening,an enhanced model Dop Net FC using chemical formulas for the dataset is adopted to predict ionic conductivity.Finally,Li_(10)SrP_(2)S_(12)(LSrPS)is screened out,which has high lithium ion conductivity(12.58 mS cm^(-1)).In addition,an enhanced migration of lithium ion across the LSr PS/Li interface is found.Meanwhile,compared to the LGPS/Li interface,LSrPS/Li interface exhibits a larger Schottky barrier(0.134 eV),smaller electron transfer region(3.103?),and enhanced ability to block additional electrons,all of which contribute to the stabilized interface.The applied theoretical atom substitution screening framework with the aid of machine learning can be extended to rapid determination of modified specific material schemes. 展开更多
关键词 Atom substitution Solid-state electrolyte Machine learning stabilized interface
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Human islet amyloid polypeptide oligomers stabilized and probed by MAS NMR
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作者 Ziwei Chang Zhengfeng Zhang 《Magnetic Resonance Letters》 2024年第1期61-62,共2页
The capture and characterization of oligomers are extremely important in the studies of amyloid aggregation of proteins and peptides.Oligomers are critical intermediates that can impact the structures of amyloid fibri... The capture and characterization of oligomers are extremely important in the studies of amyloid aggregation of proteins and peptides.Oligomers are critical intermediates that can impact the structures of amyloid fibrils.Moreover,it is widely accepted that oligomers are the most toxic species along the aggregation pathway[1e4].The studies of oligomers are believed to shed light on the molecular mechanism of amyloid fibrillation and probably the medical clues for related diseases.In vitro investigations of amyloid oligomers are challenging due to their transient and polymorphic nature[5].This is particularly evident in the case of human type-2 diabetes-associated islet amyloid polypeptide(hIAPP),which tends to rapidly form polymorphic fibrils within minutes[6].Notably,hIAPP demonstrates a higher propensity for rapid aggregation compared to other amyloid proteins such as a-synuclein[7]. 展开更多
关键词 AGGREGATION OLIGOMER stabilized
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Building stabilized Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode enables an outstanding room‐/low‐temperature aqueous Zn‐ion batteries
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作者 Ao Wang Dai‐Huo Liu +9 位作者 Lin Yang Fang Xu Dan Luo Haozhen Dou Mengqin Song Chunyan Xu Beinuo Zhang Jialin Zheng Zhongwei Chen Zhengyu Bai 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期25-35,共11页
Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this ... Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials. 展开更多
关键词 aqueous zinc‐ion batteries Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O oxygen defects room‐/lowtemperature performance stabilized nanostructure
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Mechanical behaviors of warm and ice-rich frozen soil stabilized with sulphoaluminate cement
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作者 WANG Honglei ZHANG Hu +2 位作者 ZHANG Jianming ZHANG Qi YIN Zhenhua 《Journal of Mountain Science》 SCIE CSCD 2024年第1期335-345,共11页
The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures an... The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures and foundations in permafrost regions. In this study, a novel approach for stabilizing the warm and ice-rich frozen soil with sulphoaluminate cement was proposed based on chemical stabilization. The mechanical behaviors of the stabilized soil, such as strength and stress-strain relationship, were investigated through a series of triaxial compression tests conducted at -1.0℃, and the mechanism of strength variations of the stabilized soil was also explained based on scanning electron microscope test. The investigations indicated that the strength of stabilized soil to resist failure has been improved, and the linear Mohr-Coulomb criteria can accurately reflect the shear strength of stabilized soil under various applied confining pressure. The increase in both curing age and cement mixing ratio were favorable to the growth of cohesion and internal friction angle. More importantly, the strength improvement mechanism of the stabilized soil is attributed to the formation of structural skeleton and the generation of cementitious hydration products within itself. Therefore, the investigations conducted in this study provide valuable references for chemical stabilization of warm and ice-rich frozen ground, thereby providing a basis for in-situ ground improvement for reinforcing warm and ice-rich permafrost foundations by soil-cement column installation. 展开更多
关键词 Permafrost regions Frozen soil Mechanical behavior Chemical stabilization Ground improvement Ground modification
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Surface-to-bulk engineering with high-valence W^(6+) enabling stabilized single-crystal LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cathode
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作者 Jun-Ke Liu Xue-Rui Yang +6 位作者 Chuan-Wei Wang Zu-Wei Yin Yi-Yang Hu Li Deng Zhen Wang Yao Zhou Jun-Tao Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期67-76,共10页
Single-crystal Nickel-rich layered oxides has been recognized as one of the promising cathodes for nextgeneration lithium batteries on account of their high capacity,while its practical application was hindered by str... Single-crystal Nickel-rich layered oxides has been recognized as one of the promising cathodes for nextgeneration lithium batteries on account of their high capacity,while its practical application was hindered by structural instability and slow Li^(+) transfer kinetics.Herein,a surface-to-bulk engineered single-crystal LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)(Ni90) cathode,which features W-doped bulk and Li_(2)WO_(4) surface layer,was successfully achieved by a one-step high-valence W^(6+) modification.The as-obtained W-modified Ni90 delivers excellent cycling stability(89.8% capacity retention after 300 cycles at 0.5 C)and rate capability.The enhanced electrochemical performance was ascribed to the doped-W induced stabilized lattice oxygen,reduced Li^(+)/Ni^(2+) mixing and inhibited H2-H3 phase transition in the bulk,and Li_(2)WO_(4) layer generated stabilized cathode/electrolyte interface.In addition,the thinner LiF-rich cathode electrolyte interphase(CEI) on surface and smaller grain size for W-modified Ni90 benefit to its Li^(+) diffusion dynamics.The effect of high-valence W^(6+)on single-crystal Ni-rich cathode was firstly revealed in detail,which deepens the understanding of electrochemical behavior of Ni-rich cathode with high-valence cations modification,and provides clues for design of high-performance layered cathodes. 展开更多
关键词 Single-crystal Ni-rich cathode Surface-to-bulk engineering High-valence cations Structural stability Interfacial side reaction
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Effect of CO_(2)exposure on the mechanical strength of geopolymerstabilized sandy soils
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作者 Hamid Reza Razeghi Armin Geranghadr +2 位作者 Fatemeh Safaee Pooria Ghadir Akbar A.Javadi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期670-681,共12页
In recent years,there has been growing interest in developing methods for mitigating greenhouse effect,as greenhouse gas emissions continue to contribute to global temperature rise.On the other hand,investigating geop... In recent years,there has been growing interest in developing methods for mitigating greenhouse effect,as greenhouse gas emissions continue to contribute to global temperature rise.On the other hand,investigating geopolymers as environmentally friendly binders to mitigate the greenhouse effect using soil stabilization has been widely conducted.However,the effect of CO_(2)exposure on the mechanical properties of geopolymer-stabilized soils is rarely reported.In this context,the effect of CO_(2)exposure on the mechanical and microstructural features of sandy soil stabilized with volcanic ash-based geopolymer was investigated.Several factors were concerned,for example the binder content,relative density,CO_(2)pressure,curing condition,curing time,and carbonate content.The results showed that the compressive strength of the stabilized sandy soil specimens with 20%volcanic ash increased from 3 MPa to 11 MPa.It was also observed that 100 kPa CO_(2)pressure was the optimal pressure for strength development among the other pressures.The mechanical strength showed a direct relationship with binder content and carbonate content.Additionally,in the ambient curing(AC)condition,the mechanical strength and carbonate content increased with the curing time.However,the required water for carbonation evaporated after 7 d of oven curing(OC)condition and as a result,the 14-d cured samples showed lower mechanical strength and carbonate content in comparison with 7-d cured samples.Moreover,the rate of strength development was higher in OC cured samples than AC cured samples until 7 d due to higher geopolymerization and carbonation rate. 展开更多
关键词 Soil stabilization CO_(2)effect GEOPOLYMER
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A universal multifunctional dual cation doping strategy towards stabilized ultra-high nickel cobalt-free lithium layered oxide cathode
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作者 Yabin Shen Dongming Yin +2 位作者 Limin Wang Gang Huang Yong Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期296-305,I0007,共11页
Ultra-high nickel cobalt-free lithium layered oxides are promising cathode material for lithium-ion batteries(LIBs)because of their relatively high capacity and low cost.Nevertheless,the high nickel content would indu... Ultra-high nickel cobalt-free lithium layered oxides are promising cathode material for lithium-ion batteries(LIBs)because of their relatively high capacity and low cost.Nevertheless,the high nickel content would induce bulk structure degradation and interfacial environment deterioration,and the absence of Co element reduces the lithium diffusion kinetics,severely limiting the performance liberation of this kind of cathodes.Herein,a multifunctional Ti/Zr dual cation co-doping strategy has been employed to improve the lithium storage performance of LiNi_(0.9)Mn_(0.1)O_(2)(NM91)cathode.On the one hand,the Ti/Zr co-doping weakens the Li^(+)/Ni^(2+)mixing through magnetic interactions due to the inexistence of unpaired electrons for Ti^(4+)and Zr^(4+),increasing the lithium diffusion rate and suppressing the harmful coexistence of H1 and H2 phases.On the other hand,they enhance the lattice oxygen stability because of the strong Ti-O and Zr-O bonds,inhibiting the undesired H3 phase transition and lattice oxygen loss,improving the bulk structure and cathode-electrolyte interface stability.As a result,the Ti/Zr co-doped NM91(NMTZ)exhibits a 91.2%capacity retention rate after 100 cycles,while that of NM91 is only82.9%.Also,the NMTZ displays better rate performance than NM91 with output capacities of 115 and93 mA h g^(-1)at a high current density of 5 C,respectively.Moreover,the designed NMTZ could enable the full battery to deliver an energy density up to 263 W h kg^(-1),making the ultra-high nickel cobaltfree lithium layered oxide cathode closer to practical applications. 展开更多
关键词 Lithium-ion battery Ultra-high nickel cobalt-free cathode Ti/Zr co-doping Li^(+)/Ni^(2+)mixing Lattice oxygen stability
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Effect of Aerodynamically Stabilized Seeker Dynamics on System Analysis 被引量:3
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作者 夏群力 祁载康 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期437-442,共6页
Aim To study the effect of aerodynamically stabilized seeker dynamics on guided bomb system analysis. Methods A thorough analysis of aerodynamically stabilized seeker dynamics was made to show that because of the mu... Aim To study the effect of aerodynamically stabilized seeker dynamics on guided bomb system analysis. Methods A thorough analysis of aerodynamically stabilized seeker dynamics was made to show that because of the much smaller time constant, its dynamic model can be greatly simplified. Results and Conclusion In guided bomb guidance/control digital simulation, with the use of the simplified seeker model, simulation time can be reduced without the loss of simulation accuracy. 展开更多
关键词 guided bomb aerodynamically stabilized seeker local air dislocation angle
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Effect of Friedel's salt on strength enhancement of stabilized chloride saline soil 被引量:6
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作者 CHENG Yin LI Zhan-guo +1 位作者 HUANG Xin BAI Xiao-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期937-946,共10页
In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fi... In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement(PC) and PC with Ca(OH)_2(CH) with different contents. A series of unconfined compressive strength(UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry(XRD), scanning electronic microscopy(SEM), and energy-dispersive X-ray analysis(EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel's salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel's salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils. 展开更多
关键词 CHLORIDE SALINE SOIL stabilized SOIL Friedel’s SALT strength enhancement EFFECT
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Theory-orientated discovery of high-temperature superconductors in superhydrides stabilized under high pressure 被引量:7
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作者 Jian Lv Ying Sun +1 位作者 Hanyu Liu Yanming Ma 《Matter and Radiation at Extremes》 SCIE CAS 2020年第6期88-90,共3页
A dream long held by physicists has been to raise the critical temperature(Tc)—the temperature below which the material exhibits no electrical resistance—of a superconductor to room temperature.The most recent excit... A dream long held by physicists has been to raise the critical temperature(Tc)—the temperature below which the material exhibits no electrical resistance—of a superconductor to room temperature.The most recent excitement in that regard has centered on rare-earth superhydrides,of which LaH10 at 190 GPa has a remarkably high Tc of 260 K. 展开更多
关键词 temperature. stabilized SUPERCONDUCTORS
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Simulation of bluff body stabilized flows with hybrid RANS and PDF method 被引量:4
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作者 Minming Zhu Xingsi Han Haiwen Ge Yiliang Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第3期263-273,共11页
The motivation of this study is to investigate the turbulence-chemistry interactions by using probability density function (PDF) method. A consistent hybrid Reynolds Averaged Navier-Stokes (RANS)/PDF method is use... The motivation of this study is to investigate the turbulence-chemistry interactions by using probability density function (PDF) method. A consistent hybrid Reynolds Averaged Navier-Stokes (RANS)/PDF method is used to simulate the turbulent non-reacting and reacting flows. The joint fluctuating velocity-frequency-composition PDF equation coupled with the Reynolds averaged density, momentum and energy equations are solved on unstructured meshes by the Lagrangian Monte Carlo (MC) method combined with the finite volume (FV) method. The simulation of the axisymmetric bluff body stabilized non-reacting flow fields is presented in this paper. The calculated length of the recirculation zone is in good agreement with the experimental data. Moreover, the significant change of the flow pattern with the increase of the jet-to-coflow momentum flux ratio is well predicted. In addition, comparisons are made between the joint PDF model and two different Reynolds stress models. 展开更多
关键词 Hybrid algorithm Unstructured mesh Finite volume method PDF method Bluff body stabilized flow
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Experimental evaluation of mechanically stabilized earth walls with recycled crumb rubbers 被引量:9
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作者 Matin Jalali Moghadam Amirali Zad +1 位作者 Nima Mehrannia Nader Dastaran 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第5期947-957,共11页
Traditional techniques for treatment of waste rubber, such as burning, generate some highly non- degradable synthetic materials that cause unrepairable environmental damages by releasing heavy metals, such as arsenic,... Traditional techniques for treatment of waste rubber, such as burning, generate some highly non- degradable synthetic materials that cause unrepairable environmental damages by releasing heavy metals, such as arsenic, chromium, lead, manganese and nickel. For this, scrap tires are used as light- weight alternative materials in many engineering applications, such as retaining wall backfilling. In the present study, 90 laboratory models were prepared to evaluate the stability of mechanically stabilized earth (MSE) walls with plate anchors. Then, the bearing capacity and horizontal displacements of the retaining walls were monitored by exerting a static loading to investigate the effects of adding different contents (5 wt%, 10 wt%, 15 wt% and 20 wt%) of recycled crumb rubber (RCR) to the fill of a mechanically stabilized retaining wall with plate anchors. To visualize the critical slip surface of the wall, the particle image velocimetry (PIV) technique was employed. Results showed that the circular anchor plates almost continually provided a higher bearing capacity and wall stability than the square plates. Moreover, the backfill with 15 wt% RCR provided the maximum bearing capacity of the wall. Increasing the weight percentage of RCR to 20 wt% resulted in a significant reduction in horizontal displacement of the wall, which occurred due to the decrease in lateral earth pressure against the whole walls. An increase in RCR content resulted in the decrease in the formation of failure wedge and the expansion of the wall slip surface, and the failure wedge did not form in the sand mixtures with 15 wt% and 20 wt% RCRs. 展开更多
关键词 Mechanically stabilized earth (MSE) wall Plate anchor Recycled crumb rubber (RCR) Particle image velocimetry (PIV)
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The Warming of the Tibetan Plateau in Response to Transient and Stabilized 2.0℃/1.5℃Global Warming Targets 被引量:4
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作者 Jintao ZHANG Qinglong YOU +2 位作者 Fangying WU Ziyi CAI Nick PEPIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第7期1198-1206,I0014-I0017,共13页
As "the third pole", the Tibetan Plateau(TP) is sensitive to climate forcing and has experienced rapid warming in recent decades. This study analyzes annual and seasonal near-surface air temperature changes ... As "the third pole", the Tibetan Plateau(TP) is sensitive to climate forcing and has experienced rapid warming in recent decades. This study analyzes annual and seasonal near-surface air temperature changes on the TP in response to transient and stabilized 2.0℃/1.5℃ global warming targets based on simulations of the Community Earth System Model(CESM). Elevation-dependent warming(EDW) with faster warming at higher elevations is predicted. A surface energy budget analysis is adopted to uncover the mechanisms responsible for the temperature changes. Our results indicate a clear amplified warming on the TP with positive EDW in 2.0℃/1.5℃ warmer futures, especially in the cold season. Mean TP warming relative to the reference period(1961–90) is dominated by an enhanced downward longwave radiation flux, while the variations in surface albedo shape the detailed pattern of EDW. For the same global warming level, the temperature changes under transient scenarios are ~0.2℃ higher than those under stabilized scenarios, and the characteristics of EDW are broadly similar for both scenarios. These differences can be primarily attributed to the combined effects of differential downward longwave radiation, cloud radiative forcing, and surface sensible and latent heat fluxes. These findings contribute to a more detailed understanding of regional climate on the TP in response to the long-term climate goals of the Paris Agreement and highlight the differences between transient and stabilized warming scenarios. 展开更多
关键词 elevation-dependent warming(EDW) Paris Agreement Tibetan Plateau transient and stabilized warming temperature
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Mechanism and Optimal Application of Chemical Additives for Accelerating Early Strength of Lime-flyash Stabilized Soils 被引量:3
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作者 姜增国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第3期110-112,共3页
To accelerate the early strength of lime-flyush stabilized soil for extending its further uses in highway and shortening highway constraction time, five kinds of chemical odditives were chosen on the basis of mechanis... To accelerate the early strength of lime-flyush stabilized soil for extending its further uses in highway and shortening highway constraction time, five kinds of chemical odditives were chosen on the basis of mechanism analysis of accelerating early strength in highway as a semi-rigid base materhd, and a series of experiments about the effect of differeat kinds of additives and quantity on the early strength of the stabilized soll were tested. The results show that chemical additives can efftciently improve the early strength of lime-flyush stabilized soil both the 7 d and 28d, and the optimum quantity for above chemical additive is 1.5%-2.5% approximately. Some suggestions for the practical construction were also proposed. 展开更多
关键词 LIME-FLYASH stabilized soil chemical additives early strength
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Collecting aerosol in airflow with a magnetically stabilized fluidized bed 被引量:3
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作者 Gui, KT Zhang, H +1 位作者 Shi, MH Xu, YQ 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期497-501,共5页
A magnetically stabilized fluidized bed (MSB) is a highly efficient filter that takes the advantage of both fluidized beds and fixed beds. This paper presents the research to collect aerosol in airflow with a MSB. The... A magnetically stabilized fluidized bed (MSB) is a highly efficient filter that takes the advantage of both fluidized beds and fixed beds. This paper presents the research to collect aerosol in airflow with a MSB. The filtering model of MSB is established with its parameters including magnetic Geld intensity, gas superficial velocity, average grain-size, and bed height on the collection efficiency of MSB. The model is verified by experiments. 展开更多
关键词 magnetically stabilized fluidized bed filtering model collection efficiency
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Robust control with compensation of adaptive model for dual-stage inertially stabilized platform 被引量:3
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作者 SONG Jiang-peng ZHOU Di +1 位作者 SUN Guang-li QI Zhi-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第11期2615-2625,共11页
To achieve excellent tracking accuracy,a coarse-fine dual-stage control system is chosen for inertially stabilized platform.The coarse stage is a conventional inertially stabilized platform,and the fine stage is a sec... To achieve excellent tracking accuracy,a coarse-fine dual-stage control system is chosen for inertially stabilized platform.The coarse stage is a conventional inertially stabilized platform,and the fine stage is a secondary servo mechanism to control lens motion in the imaging optical path.Firstly,the dual-stage dynamics is mathematically modeled as a coupling multi-input multi-output(MIMO)control system.Then,by incorporating compensation of adaptive model to deal with parameter variations and nonlinearity,a systematic robust H∞control scheme is designed,which can achieve good tracking performance,as well as improve system robustness against model uncertainties.Lyapunov stability analysis confirmed the stability of the overall control system.Finally,simulation and experiment results are provided to demonstrate the feasibility and effectiveness of the proposed control design method. 展开更多
关键词 dual-stage control inertially stabilized platform robust H∞control adaptive model
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A High-Temperature β-Phase NaMnO2 Stabilized by Cu Doping and Its Na Storage Properties 被引量:3
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作者 Li-Wei Jiang Ya-Xiang Lu +5 位作者 Yue-Sheng Wang Li-Lu Liu Xing-Guo Qi Cheng-Long Zhao Li-Quan Chen Yong-Sheng Hu 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第4期132-135,共4页
The high-temperature β-phase NaMnO2 is a promising material for Na-ion batteries(NIBs) due to its high capacity and abundant resources. However, the synthesis of phase-pure -NaMnO2 is burdensome and costineffective... The high-temperature β-phase NaMnO2 is a promising material for Na-ion batteries(NIBs) due to its high capacity and abundant resources. However, the synthesis of phase-pure -NaMnO2 is burdensome and costineffective because it needs to be sintered under oxygen atmosphere at high temperature and followed by a quenching procedure. Here we first report that the pure β phase can be stabilized by Cu-doping and easily synthesized by replacing a proportion of Mn with Cu via a simplified process including sintering in air and cooling to room temperature naturally. Based on the first-principle calculations, the band gap decreases from 0.7 eV to 0.3 eV, which indicates that the electronic conductivity can be improved by Cu-doping. The designed -NaCu(0.1)Mn(0.9)O2 is applied as cathode in NIBs, exhibiting an energy density of 419 Wh/kg and better performance in terms of rate capability and cycling stability than those in the undoped case. 展开更多
关键词 NA A High-Temperature Phase NaMnO2 stabilized by Cu Doping and Its Na Storage Properties Mn Cu
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Effect of Rubber Particles on Cement Stabilized Gravel System 被引量:2
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作者 杨若冲 李凯 +3 位作者 ZHU Jipeng ZHU Tengkuo DONG Zheng WU Dengcheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第5期990-995,共6页
The primary objective of this paper was to study the mechanical properties and durability of the cement stabilized gravel by different compact method. The influence of rubber particle content on mechanical properties ... The primary objective of this paper was to study the mechanical properties and durability of the cement stabilized gravel by different compact method. The influence of rubber particle content on mechanical properties of samples was studied by compaction tests and freezing thawing recycle tests. Pore structure and fractal characteristic of mixture were analyzed quantitatively using mercury intrusion porosimetry (MIP). X-ray diffraction (XRD) was adopted to identify the composition phases. The morphology analysis in micro scale and elemental analysis of samples were carried out by scanning electron microscope (SEM). The optimum compressive strengths of rubber cement stabilized gravel (RCSG) with static compaction method and with vibratory compaction method were obtained by controlling compaction degree and vibration time, respectively. From the compaction tests, the vibratory compaction method is preferred compared with the static compaction method as better compressive strength can be improved by about 340%-360%. Besides, test results also reveal that compressive strength of samples with vibratory compaction method or static compaction method will decrease with the rubber particle bulk content increasing. The freezing thawing recycle tests indicate that freezing thawing resistance has been improved (frozen stability coefficient K has been increased from 0.89 to 0.97) by the addition of rubber particles. MIP tests show that the mean pore diameter and porosity of mixture have been increased from 70 to 250 nm and 9% to 24% respectively, with the rubber particles content increasing. Component analysis shows that the calcium silicate hydrate (CSH) is the predominant hydrate product with or without the addition of rubber particles. 展开更多
关键词 PAVEMENT rubber cement stabilized gravel mechanical property SEM MIP
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Parameter identification of inertially stabilized platforms using current command design 被引量:2
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作者 黎志强 张智永 +1 位作者 周擎坤 范大鹏 《Journal of Central South University》 SCIE EI CAS 2013年第2期342-353,共12页
Accurate parameter identification is essential when designing controllers for inertially stabilized platforms (lSPs). But traditional identification methods suffer from observation measurement noise and operating re... Accurate parameter identification is essential when designing controllers for inertially stabilized platforms (lSPs). But traditional identification methods suffer from observation measurement noise and operating restrictions of ISPs. To address this issue, a novel identification method based on current command design and multilevel coordinate search (MCS) algorithm without any higher order measurement differentiations was proposed. The designed current commands were adopted to obtain parameter decoupled models with the platform operating under allowable conditions. MCS algorithm was employed to estimate the parameters based on parameter decoupled models. A comparison experiment between the proposed method and non-linear least square method was carried out and most of the relative errors of identified parameters obtained by the proposed method were below 10%. Simulation and experiment based on identified parameters were conducted. A velocity control structure was also developed with disturbance observer (DOB) for application in disturbance compensation control system of an ISR Experimental results show that the control scheme based on the identified parameters with DOB has the best disturbance rejection performance. It reduces the peak to peak value (PPV) of velocity error integral to 0.8 mrad which is much smaller than the value (10 mrad) obtained by the single velocity controller without DOB. Compared with the control scheme based on sweep model with DOB compensation, the proposed control scheme improves the PPV of velocity error integral by 1.625 times. 展开更多
关键词 parameter identification current command design multilevel coordinate search inertially stabilized platforms
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Handily etching nickel foams into catalyst-substrate fusion self‐stabilized electrodes toward industrial‐level water electrolysis 被引量:2
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作者 Zexuan Zhu Xiaotian Yang +2 位作者 Jiao Liu Mingze Zhu Xiaoyong Xu 《Carbon Energy》 SCIE EI CAS CSCD 2023年第10期2-12,共11页
The key challenge of industrial water electrolysis is to design catalytic electrodes that can stabilize high current density with low power consumption(i.e.,overpotential),while industrial harsh conditions make the ba... The key challenge of industrial water electrolysis is to design catalytic electrodes that can stabilize high current density with low power consumption(i.e.,overpotential),while industrial harsh conditions make the balance between electrode activity and stability more difficult.Here,we develop an efficient and durable electrode for water oxidation reaction(WOR),which yields a high current density of 1000 mA cm−2 at an overpotential of only 284 mV in 1M KOH at 25°C and shows robust stability even in 6M KOH strong alkali with an elevated temperature up to 80°C.This electrode is fabricated from a cheap nickel foam(NF)substrate through a simple one-step solution etching method,resulting in the growth of ultrafine phosphorus doped nickel-iron(oxy)hydroxide[P-(Ni,Fe)O_(x)H_(y)]nanoparticles embedded into abundant micropores on the surface,featured as a self-stabilized catalyst–substrate fusion electrode.Such self-stabilizing effect fastens highly active P-(Ni,Fe)O_(x)H_(y)species on conductive NF substrates with significant contribution to catalyst fixation and charge transfer,realizing a win–win tactics for WOR activity and durability at high current densities in harsh environments.This work affords a cost-effective WOR electrode that can well work at large current densities,suggestive of the rational design of catalyst electrodes toward industrial-scale water electrolysis. 展开更多
关键词 alkaline water electrolysis industrially relevant conditions oxygen evolution reaction self‐stabilized electrodes
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