期刊文献+
共找到527篇文章
< 1 2 27 >
每页显示 20 50 100
Effect of Nb Addition on Tensile and Wear Properties of 18Ni300 Mold Steel Fabricated by LPBF
1
作者 Jian Changhuang Yang Yang +5 位作者 Wang Chengyong Yu Bowen Niu Liuhui Hu Gaofeng Liu Jianye Huang Zhenghua 《稀有金属材料与工程》 北大核心 2026年第1期18-26,共9页
Laser powder bed fusion(LPBF)is highly suitable for forming 18Ni300 mold steel,thanks to its excellent capability in manufacturing complex shapes and outstanding capacity for regulating microstructures.It is widely us... Laser powder bed fusion(LPBF)is highly suitable for forming 18Ni300 mold steel,thanks to its excellent capability in manufacturing complex shapes and outstanding capacity for regulating microstructures.It is widely used in fields such as injection molding,die casting,and stamping dies.Adding reinforcing particles into steel is an effective means to improve its performance.Nb/18Ni300 composites were fabricated by LPBF using two kinds of Nb powders with different particle sizes,and their microstructures and properties were studied.The results show that the unmelted Nb particles are uniformly distributed in the 18Ni300 matrix and the grains are refined,which is particularly pronounced with fine Nb particles.In addition,element diffusion occurs between the particles and the matrix.The main phases of the base alloy are α-Fe and a small amount of γ-Fe.With the addition of Nb,part of the α-Fe is transformed into γ-Fe,and unmelted Nb phases appear.The addition of Nb also enhances the hardness and wear resistance of the composites but slightly reduces their tensile properties.After aging treatment,the molten pools and grain boundaries become blurred,grains are further refined,and the interfaces around the particles are thinned.The aging treatment also promotes the formation of reverted austenite.The hardness,ultimate tensile strength,and volumetric wear rate of the base alloy reach 51.9 HRC,1704 MPa,and 17.8×10^(-6) mm^(3)/(N·m),respectively.In contrast,the sample added with fine Nb particles has the highest hardness(56.1 HRC),ultimate tensile strength(1892 MPa)and yield strength(1842 MPa),and the volume wear rate of the sample added with coarse Nb particles is reduced by 90%to 1.7×10^(-6) mm^(3)/(N·m). 展开更多
关键词 laser powder bed fusion 18Ni300 mold steel Nb addition microstructure mechanical property
原文传递
Effect of Thermoelectric Cooler Arrangements on Thermal Performance and Energy Saving in Electronic Applications:An Experimental Study
2
作者 M.N.Abd-Al Ameer Iman S.Kareem Ali A.Ismaeel 《Energy Engineering》 2026年第1期511-526,共16页
Electrical and electronic devices face significant challenges in heatmanagement due to their compact size and high heat flux,which negatively impact performance and reliability.Conventional coolingmethods,such as forc... Electrical and electronic devices face significant challenges in heatmanagement due to their compact size and high heat flux,which negatively impact performance and reliability.Conventional coolingmethods,such as forced air cooling,often struggle to transfer heat efficiently.In contrast,thermoelectric coolers(TECs)provide an innovative active cooling solution to meet growing thermal management demands.In this research,a refrigerant based on mono ethylene glycol and distilled water was used instead of using gases,in addition to using thermoelectric cooling units instead of using a compressor in traditional refrigeration systems.This study evaluates the performance of a Peltierbased thermalmanagement systemby analyzing the effects of using two,three,and four Peltiermodules on cooling rates,power consumption,temperature reduction,and system efficiency.Experimental results indicate that increasing the number of Peltier modules significantly enhances cooling performance.The four-module system achieved an optimal balance between cooling speed and energy efficiency,reducing the temperature of a liquidmixture(30% mono ethylene glycol+70% distilled water plus laser dyes)to 8℃ in just 17 min.It demonstrated a cooling rate of 0.794℃/min and a high coefficient of performance(COP)of 1.2 while consuming less energy than the two-and three-module systems.Furthermore,the study revealed that increasing the number of modules led to faster air cooling and improved temperature reduction.These findings highlight the importance of selecting the optimal number of Peltier modules to enhance efficiency and cooling speed whileminimizing energy consumption.This makes TEC technology a sustainable and effective solution for applications requiring rapid and reliable thermal management. 展开更多
关键词 Energy consumption mono ethylene glycol Peltier effect performance factor(COP)
在线阅读 下载PDF
Environmental Sustainability through Waste-to-Wealth Automotive Oil Usage in a Thermal Storage System Integrated with Circulating-Air Solar Air Heater
3
作者 Shaymaa Husham Abdulmalek Ali Ahmed Gitan +2 位作者 Israa Sami Farhan Oras Fadhil Khalaf Sayf Waleed Albayati 《Energy Engineering》 2026年第3期117-131,共15页
The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heat... The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heater(SAH)integrated with an internal thermal storage unit using Waste Automotive Oil(WAO).The SAH was designed based on the circulation of confined air around the internal thermal storage unit due to the updraft effects of hot air.Two SAHs were tested to compare the performance of WAO and water,with the results being compared to previous work that utilised phase change material.Results showed that WAO responds faster in the early stage,while water has slightly higher daytime efficiency,with a maximum temperature of 60℃,while WAO reached a maximum temperature of 76℃.During the discharge cycle,WAO achieved an efficiency of 65.7%,while the water’s efficiency 73.2% within the same period.The highest outlet air temperatures recorded were 43℃ for WAO and 33.8℃ for water.These findings support that water is suitable for applications requiring rapid thermal charging,while WAO offers extended thermal stability.The study highlights the feasibility of using low-cost materials,such as WAO and water,to enhance the performance of solar energy systems,thereby making them more viable for industrial applications like drying and heating. 展开更多
关键词 Solar air heater phase change materials(PCM) thermal performance thermal storage waste oil
在线阅读 下载PDF
A Comparative Review of the Experimental Mitigation Methods of the S-Shaped Diffusers in the Aeroengine Intakes
4
作者 Hussain H.Al-Kayiem Safaa M.Ali +1 位作者 Sundus S.Al-Azawiey Raed A.Jessam 《Energy Engineering》 2026年第2期68-103,共36页
Gas Turbines are among the most important energy systems for aviation and thermal-based power generation.The performance of gas turbine intakes with S-shaped diffusers is vulnerable to flow separation,reversal flow,an... Gas Turbines are among the most important energy systems for aviation and thermal-based power generation.The performance of gas turbine intakes with S-shaped diffusers is vulnerable to flow separation,reversal flow,and pressure distortion,mainly in aggressive S-shaped diffusers.Severalmethods,including vortex generators and energy promoters,have been proposed and investigated both experimentally and numerically.This paper compiles a review of experimental investigations that have been performed and reported to mitigate flow separation and restore system performance.The operational principles,classifications,design geometries,and performance parameters of Sshaped diffusers are presented to facilitate the analysis and understanding of the influence of each mitigation method on flowenhancement in S-shaped diffusers.Theinfluencing design parameters on the performance of the S-shaped diffuser and the findings achieved by various experimental investigations are discussed and compared.The review concludes that reducing the intake length reduces the size and weight of the gas turbine,leading to a higher power-to-weight ratio.However,the main challenge in shortening the S-shaped diffusers is the flow separation in the high-curvature section,which must be prevented to maintain high performance.Prevention can be achieved through flow control methods,which are categorized into passive and aggressive methods.The static pressure recovery coefficient,total pressure loss coefficient,ideal static pressure coefficient,distortion coefficient,and skin friction coefficient are the primary performance evaluation and comparison parameters between the experimentally investigated mitigation methods.The new trend in S-shaped diffuser studies includes the integration of computational and data-driven methods. 展开更多
关键词 Active flow control AEROENGINE air intake distortion coefficient gas turbine passive flow control pressure recovery S-shaped diffuser
在线阅读 下载PDF
Analysis of Geometrical Arrangement and Packing Material on Heat Generation in Lithium-Ion Battery Banks
5
作者 Seenaa Khudhayer Salman Shaymaa Husham Abdulmalek +2 位作者 Ali Ahmed Gitan Thamer Khalif Salem Raaid Rashad Jassem Al-Doury 《Energy Engineering》 2026年第2期578-601,共24页
Operating Lithium-ion batteries at their temperature limits is a challenging design task due to explosion risk at high temperatures and rapid degradation at low temperatures.Depending on the battery package design,tho... Operating Lithium-ion batteries at their temperature limits is a challenging design task due to explosion risk at high temperatures and rapid degradation at low temperatures.Depending on the battery package design,those risks can be solved with passive solutions,which require no active cooling or heating.Thecurrentwork aims to optimize the pack design and materials of the type-NCR18650B battery based on a wide range of operation temperature.The lower limit was denoted by cold case while the maximum limit was expressed by hot case.A combined analyticalnumerical approach was developed to model the heat generation inside the battery.A thermal resistance analysis was used to determine the boundary conditions of the numerical model.The governing differential equations for the 1-D heat generation model were solved analytically.The numerical analysis was considered to determine the best battery pack design based on material parameters,number of batteries,and geometrical arrangement.The analytical results revealedthat the cold case canbe selectedas theworst case and thebestmodel wasobtainedusing thehexagonal-shaped 10-battery pack that was covered with Delrin of 1.8 mm in thickness.The numerical results showed that the best model was the hexagonal-shaped 10-battery pack with Delrin of 2 mm in thickness that achieved the largest temperature of−20.6℃ in the cold case. 展开更多
关键词 Analytical analysis battery package battery package configuration battery packing safety lithium-ion battery thermal performance
在线阅读 下载PDF
Ultrahigh Electromagnetic Interference Shielding and Integrated Thermal Sensing-encryption Enabled by a Honeycomb-inspired Multifunctional Foam
6
作者 Shao-Peng Yu Ya Liu +4 位作者 Ming-Yu Hao Xin Zhang Xu Zhang Yi-Cheng Yuan Zhen-Xiu Zhang 《Chinese Journal of Polymer Science》 2026年第2期513-524,I0016,共13页
With the rapid development of intelligent electronic and military equipment,multifunctional flexible materials that integrat electromagnetic interference(EMI)shielding,temperature sensing,and information encryption ar... With the rapid development of intelligent electronic and military equipment,multifunctional flexible materials that integrat electromagnetic interference(EMI)shielding,temperature sensing,and information encryption are urgently required.This study presents a bio-inspired hierarchical composite foam fabricated using supercritical nitrogen foaming technology.This material exhibits a honeycomb structure,with pore cell sizes controllable within a range of 30–92μm by regulating the filler.The carbon fiber felt(CFf)provides efficient reflection of electromagnetic waves,while the chloroprene rubber/carbon fiber/carbon black foam facilitates both wave absorption and temperature monitoring through its optimized conductive network.This synergistic mechanism results in an EMI shielding effectiveness(SE)of 60.06 d B with excellent temperature sensing performance(The temperature coefficient of resistance(TCR)is-2.642%/℃)in the 24–70℃ range.Notably,the material has a thermal conductivity of up to 0.159 W/(m·K),and the bio-inspired layered design enables information encryption,demonstrating the material's potential for secure communication applications.The foam also has tensile properties of up to 5.13 MPa and a tear strength of 33.02 N/mm.This biomimetic design overcomes the traditional limitations of flexible materials and provides a transformative solution for next-generation applications such as flexible electronics,aerospace systems and military equipment,which urgently need integrated electromagnetic protection,thermal management and information security. 展开更多
关键词 FLEXIBILITY Cellular structures Electromagnetic interference shielding Temperature sensor Message encryption
原文传递
A Bio-inspired Bubble Artificial Muscles and TacTip Perception-driven Tri-legged Robot for Obstacle Avoidance
7
作者 Chaoqun Xiang Zhengwei Zhong +3 位作者 Wenqiang Wu Xiaocong Chen Yisheng Guan Tao Zou 《Journal of Bionic Engineering》 2026年第1期175-191,共17页
Legged robots have considerable potential for traversing unstructured situations;nonetheless,their inflexible frameworks often constrain adaptability and obstacle negotiation.The study article presents a revolutionary... Legged robots have considerable potential for traversing unstructured situations;nonetheless,their inflexible frameworks often constrain adaptability and obstacle negotiation.The study article presents a revolutionary Soft Tri-Legged Robot(STLR)that improves movement and obstacle-avoidance skills by using a bio-inspired pneumatic artificial muscle(Bubble Artificial Muscles)and a bio-inspired tactile sensor(TacTip).The STLR is activated by BAMs,which are flexible,pneu-matic-driven actuators that provide fine control over forward,backward,and steering movements.Obstacle identification and avoidance are facilitated by the TacTip sensor,which delivers tactile input for traversing unstructured terrains.We delineate the mechanical features of the BAMs,assess the functionality of the robot's legs,and elaborate on the incorpora-tion of the tactile sensing system.Experimental results demonstrate that the STLR can effectively achieve multi-directional flexible movement and obstacle avoidance through a cross-modal perception-actuation mechanism.This study highlights the promise of soft robotics for search and rescue,medical aid,and autonomous exploration,while delineating difficulties and opportunities for future improvements in functionality and efficiency. 展开更多
关键词 Legged robot Bio-inspired bubble artificial muscles Bio-inspired TacTip sensor Foot tactile perception Obstacle avoidance
在线阅读 下载PDF
Corrosion engineering boosting bulk Fe_(50)Mn_(30)Co_(10)Cr_(10)high-entropy alloy as high-efficient alkaline oxygen evolution reaction electrocatalyst 被引量:8
8
作者 Pengfei Zhou Dong Liu +7 位作者 Yuyun Chen Mingpeng Chen Yunxiao Liu Shi Chen Chi Tat Kwok Yuxin Tang Shuangpeng Wang Hui Pan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第14期267-275,共9页
Oxygen evolution reaction(OER)is a critical process in electrocatalytic water splitting.However,the development of low-cost,highly efficient OER electrocatalysts by a simple method that can be used for industrial appl... Oxygen evolution reaction(OER)is a critical process in electrocatalytic water splitting.However,the development of low-cost,highly efficient OER electrocatalysts by a simple method that can be used for industrial application on a large scale is still a huge challenge.Recently,high entropy alloy(HEA)has acquired extensive attention,which may provide answers to the current dilemma.Here,we report bulk Fe_(50)Mn_(30)Co_(10)Cr_(10),which is prepared by 3D printing on a large scale,as electrocatalyst for OER with high catalytic performance.Especially,an easy approach,corrosion engineering,is adopted for the first time to build an active layer of honeycomb nanostructures on its surface,leading to ultrahigh OER performance with an overpotential of 247 mV to achieve a current density of 10 mA cm^(-2),a low Tafel slope of 63 mV dec^(-1),and excellent stability up to 60 h at 100 mA cm^(-2)in 1 M KOH.The excellent catalytic activity mainly originates from:(1)the binder-free self-supported honeycomb nanostructures and multi-component hydroxides,which improve intrinsic catalytic activity,provide rich active sites,and reduce interfacial resistance;and(2)the diverse valence states for multiple active sites to enhance the OER kinetics.Our findings show that corrosion engineering is a novel strategy to improve the bulk HEA catalytic performance.We expect that this work would open up a new avenue to fabricate large-scale HEA electrocatalysts by 3D printing and corrosion engineering for industrial applications. 展开更多
关键词 ELECTROCATALYSIS High entropy alloy Corrosion engineering SELF-SUPPORTING Oxygen evolution reaction
原文传递
Reliability evaluation method and algorithm for electromechanical product 被引量:2
9
作者 刘勇军 范晋伟 李云 《Journal of Central South University》 SCIE EI CAS 2014年第10期3753-3761,共9页
The reliability of electromechanical product is usually determined by the fault number and working time traditionally. The shortcoming of this method is that the product must be in service. To design and enhance the r... The reliability of electromechanical product is usually determined by the fault number and working time traditionally. The shortcoming of this method is that the product must be in service. To design and enhance the reliability of the electromechanical product, the reliability evaluation method must be feasible and correct. Reliability evaluation method and algorithm were proposed. The reliability of product can be calculated by the reliability of subsystems which can be gained by experiment or historical data. The reliability of the machining center was evaluated by the method and algorithm as one example. The calculation result shows that the solution accuracy of mean time between failures is 97.4% calculated by the method proposed in this article compared by the traditional method. The method and algorithm can be used to evaluate the reliability of electromechanical product before it is in service. 展开更多
关键词 reliability evaluation mean time between failures probability density function electromechanical product
在线阅读 下载PDF
Controllable oxygen vacancies and morphology engineering:Ultra-high HER/OER activity under base–acid conditions and outstanding antibacterial properties 被引量:4
10
作者 Hongyao Xue Alan Meng +2 位作者 Tongqing Yang Zhenjiang Li Chunjun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期639-651,I0017,共14页
Introducing vacancy defects and unique morphology is an effective strategy to improve the catalytic performance of transition metal compounds.However,precisely controlling the amount of vacancy defects remains challen... Introducing vacancy defects and unique morphology is an effective strategy to improve the catalytic performance of transition metal compounds.However,precisely controlling the amount of vacancy defects remains challenging.Here,we propose a facile and efficient hydrothermal accompanying an annealing method to synthesize a series of Mn-doped CoO nanomaterials with controllable oxygen vacancies and unique morphology.The oxygen vacancies amount can be precisely controlled by adjusting the Mndoping content and is positively correlated with catalytic performance.It was found that the oxygen vacancies amount can reach up to 38.2%over the Mn-doped CoO nanomaterials,resulting in ultra-high hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalytic activity(HER:25.6 and 37 m V at 10 m A cm^(-2);OER:301 and 322 m V at 50 m A cm^(-2))under both basic and acidic conditions,while reaching 10 m A cm^(-2) for an ultra-low cell voltage of only 1.52 V,which exceeds that of Pt/C/RuO_(2) and all reported non-noble metal oxide catalysts.The DFT calculations reveal oxygen vacancies can optimize H*and HOO*intermediates adsorption free energy,thus improving the HER and OER performance.Interestingly,the Mn-doped CoO with rich oxygen vacancies exhibits excellent antibacterial properties in vitro of biomedicine.This work provides new ideas and methods for the rational design and precise control of vacancy defects in transition metal compounds and explores their potential application value in electrochemical water splitting and biomedical fields. 展开更多
关键词 Oxygen vacancies Mn-doping HER OER ANTIBACTERIAL
在线阅读 下载PDF
A Review of Nano/Micro/Milli Needles Fabrications for Biomedical Engineering 被引量:2
11
作者 Bin Liu Xin Yi +6 位作者 Ying Zheng Zhishan Yuan Jingbo Yang Jian Yang Xiao Yu Lelun Jiang Chengyong Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第3期51-79,共29页
Needles,as some of the most widely used medical devices,have been effectively applied in human disease prevention,diagnosis,treatment,and rehabilitation.Thin 1D needle can easily penetrate cells/organs by generating h... Needles,as some of the most widely used medical devices,have been effectively applied in human disease prevention,diagnosis,treatment,and rehabilitation.Thin 1D needle can easily penetrate cells/organs by generating highly localized stress with their sharp tips to achieve bioliquid sampling,biosensing,drug delivery,surgery,and other such applications.In this review,we provide an overview of multiscale needle fabrication techniques and their biomedical applications.Needles are classified as nanoneedles,microneedles and millineedles based on the needle diameter,and their fabrication techniques are highlighted.Nanoneedles bridge the inside and outside of cells,achieving intracellular electrical recording,biochemical sensing,and drug delivery.Microneedles penetrate the stratum corneum layer to detect biomarkers/bioelectricity in interstitial fluid and deliver drugs through the skin into the human circulatory system.Millineedles,including puncture,syringe,acupuncture and suture needles,are presented.Finally,conclusions and future perspectives for next-generation nano/micro/milli needles are discussed. 展开更多
关键词 NANONEEDLES MICRONEEDLES Millineedles Fabrication methods Biomedical Engineering
在线阅读 下载PDF
Fringe Projection Measurement System in Reverse Engineering 被引量:1
12
作者 林朝辉 何海涛 +3 位作者 郭红卫 陈明仪 石璇 俞涛 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期153-158,共6页
Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed,... Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed, developed and made applicable. This paper introduces a three dimensional opt ical measurement method based on digital fringe projection technique in RE to im prove the technique through its application. A practical example is presented an d the result demonstrates the applicability and feasibility of the measurement s ystem as well as the reliability and validity of relevant methods and algorithms . 展开更多
关键词 reverse engineering 3D optical measurement fring e projection multi-aperture overlap-scanning technique (MAOST) surface fitti ng.
在线阅读 下载PDF
Atomic insights of electronic states engineering of GaN nanowires by Cu cation substitution for highly efficient lithium ion battery 被引量:1
13
作者 Zhenjiang Li Kesheng Gao +10 位作者 Ying Han Shiqi Ding Yanglansen Cui Minmin Hu Jian Zhao Meng Zhang Alan Meng Jimmy Yun Zhiming Liu Da-Wei Wang Changlong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期46-54,共9页
Electronic engineering of gallium nitride(Ga N) is critical for enhancement of its electrode performance.In this work, copper(Cu) cation substituted Ga N(Cu-Ga N) nanowires were fabricated to understand the electronic... Electronic engineering of gallium nitride(Ga N) is critical for enhancement of its electrode performance.In this work, copper(Cu) cation substituted Ga N(Cu-Ga N) nanowires were fabricated to understand the electronically engineered electrochemical performance for Li ion storage. Cu cation substitution was revealed at atomic level by combination of X-ray photoelectron spectroscopy(XPS), X-ray absorption fine structure(XAFS), density functional theory(DFT) simulation, and so forth. The Cu-Ga N electrode delivered high capacity of 813.2 m A h g^(-1) at 0.1 A g^(-1) after 200 cycles, increased by 66% relative to the unsubstituted Ga N electrode. After 2000 cycles at 10 A g^(-1),the reversible capacity was still maintained at326.7 m A h g^(-1). The DFT calculations revealed that Cu substitution introduced the impurity electronic states and efficient interatomic electron migration, which can enhance the charge transfer efficiency and reduce the Li ion adsorption energy on the Cu-Ga N electrode. The ex-situ SEM, TEM, HRTEM, and SAED analyses demonstrated the reversible intercalation Li ion storage mechanism and good structural stability. The concept of atomic-arrangement-assisted electronic engineering strategy is anticipated to open up opportunities for advanced energy storage applications. 展开更多
关键词 Cu cation substitution Electronic states engineering GaN nanowires Lithium-ion batteries DFT
在线阅读 下载PDF
CHARACTERISTICS OF STRENGTH CONTROL OF ADAPTIVE STRUCTURE WITH ELECTROMECHANICAL COUPLING
14
作者 Sui Yunkang Shao jianyi 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第1期49-61,共13页
Based on the programming method, an electromechanical coupling adaptive statically indeterminate truss structure is controlled for increasing its load capacity. Several main parameters during the process of design of ... Based on the programming method, an electromechanical coupling adaptive statically indeterminate truss structure is controlled for increasing its load capacity. Several main parameters during the process of design of the adaptive structure are selected for a study of its characteristic during the control stage. The curves of each parameter for the effect of control results are plotted and corresponding conclusions are drawn. Thus, the theoretical basis is presented for optimal design, manufacture and control of the adaptive structure. 展开更多
关键词 adaptive structure strength control characteristic research electromechanical coupling selection of parameters
在线阅读 下载PDF
Lithiation-induced controllable vacancy engineering for developing highly active Ni_(3)Se_(2) as a high-rate and large-capacity battery-type cathode in hybrid supercapacitors
15
作者 Yinna He Ting Liu +8 位作者 Jiangnan Song Yiwei Wang Yuxiao Zhang Jie Feng Alan Meng Guicun Li Lei Wang Jian Zhao Zhenjiang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期37-46,I0002,共11页
The poor rate capability and low capacity are huge barriers to realize the commercial applications of battery-type transition metal compounds(TMCs) cathode.Herein,numerous Se vacancy defects are introduced into the Ni... The poor rate capability and low capacity are huge barriers to realize the commercial applications of battery-type transition metal compounds(TMCs) cathode.Herein,numerous Se vacancy defects are introduced into the Ni_(3)Se_(2)lamellas by pre-lithiation technique,which can be acted as a novel class of battery-type cathode for hybrid supercapacitors.Appropriately modulating the contents of the preembedded lithium(Li) ions can induce a controllable vacancy content in the series of as-prepared products,effectively endowing a fast reaction kinetic and high activity for the cathode.Benefiting from the distinct design,the optimized cathode(Li2-Ni_(3)Se_(2)) presents a high specific capacity of 236 mA h g^(-1)at1 A g^(-1),importantly,it can still possess 117 mA h g^(-1)when the current density is increased up to 100A g^(-1),exhibiting relatively high rate capability.It is much superior to other battery-type TMC cathodes reported in previous studies.Moreover,the cathode also shows the excellent cycling stability with 92%capacity retention after 3,000 cycles.In addition,a hybrid supercapacitor(HSC) is assembled with the obtained Li2-Ni_(3)Se_(2)as the cathode and active carbon(AC) as the anode,which delivers a high energy density of 77 W h kg^(-1)at 4 kW kg^(-1)and long-term durability(90% capacitance retention after 10,000 cycles).Therefore,the strategy not only provides an effective way to realize the controllable vacancy content in TMCs for achieving high-perfo rmance cathodes for HSC,but also further promotes their large-scale applications in the energy storage fields. 展开更多
关键词 Pre-lithiation Selenium vacancies High-rate Battery-type cathode Hybrid supercapacitor
在线阅读 下载PDF
Defects and morphology engineering for constructing V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S nanotube heterojunction arrays toward efficient bifunctional electrocatalyst for overall water splitting
16
作者 Wenyuan Sun Alan Meng +4 位作者 Lei Wang Guicun Li Jinfeng Cui Yongkai Sun Zhenjiang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期29-40,共12页
The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great challenge.Herein,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube he... The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great challenge.Herein,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube heterojunction arrays were in-situ grown on copper foam(V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF)for efficient electrocatalytic overall water splitting.With the merits of nanotube arrays and efficient electronic mod-ulation drived by the OD vacancy defect and 2D heterojunction defect,the resultant V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF electrocatalyst exhibits excellent electrocatalytic activity with a low overpotential of 47 mV for the hydrogen evolution reaction(HER)at 10 mA cm^(-2) current density,and 263 mV for the oxygen evolution reaction(OER)at 50 mA cm^(-2) current density,as well as a cell voltage of 1.48 V at 10 mA cm^(-2).Moreover,the nanotube heterojunction arrays endows V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF with outstanding stability in long-term catalytic processes,as confirmed by the continuous chronopotentiom-etry tests at current densities of 10 mA cm^(-2) for 100 h. 展开更多
关键词 Nanotubearrays HETEROJUNCTION VACANCY Bifunctional electrocatalyst Overall water splitting
在线阅读 下载PDF
Electromechanical Aspects of an Experimental Hybrid Vehicle
17
作者 Silvano R. Rossi Roberto J. de la Vega +5 位作者 Roberto C. Leegstra Guillermo A. Santillan Patricia M. Ciancio Marcelo A. Spina Maria H. Peralta Leonel O. Pico 《Journal of Mechanics Engineering and Automation》 2015年第6期355-361,共7页
The design and construction of an experimental solar hybrid vehicle based on the combination of photovoltaic solar energy as the main source of electricity and electric power supplied by a generator activated by the d... The design and construction of an experimental solar hybrid vehicle based on the combination of photovoltaic solar energy as the main source of electricity and electric power supplied by a generator activated by the driver's pedaling is introduced. The vehicle has a battery to store the energy provided by both systems. The development was motivated by a Latin American solar car race through the Atacama Desert in Chile and the initiative to promote the use of clean energy for transport. A general description of the vehicle, its energetic aspects and experimental results are presented. 展开更多
关键词 Clean energy solar energy solar hybrid vehicle zero emission.
在线阅读 下载PDF
Hidden Dangers and Solutions in the Installation of Electromechanical Equipment
18
作者 BAO Shihua ZHOU Chunhui 《外文科技期刊数据库(文摘版)工程技术》 2021年第10期407-409,共5页
In the process of mechanical and electrical equipment installation quality will directly affect the mechanical and electrical equipment operation quality and efficiency in the late, so the staff in the process of inst... In the process of mechanical and electrical equipment installation quality will directly affect the mechanical and electrical equipment operation quality and efficiency in the late, so the staff in the process of installation of electromechanical equipment need pay attention to some possible concerns, adopt scientific and effective way to as much as possible to reduce or avoid these hazards, so as to guarantee the quality in the process of mechanical and electrical equipment installation, which improves the efficiency and safety of mechanical and electrical equipment operation. Based on this, with the author's project, home air-conditioning, commercial air conditioning and core components as the research case, in the process of the project electrical and mechanical equipment installation exist some hidden dangers are analyzed and discussed, and puts forward some scientific and effective solution, in order to reduce the hidden dangers in the process of mechanical and electrical equipment installation, so as to improve installation quality and operation efficiency of equipment. 展开更多
关键词 ELECTROMECHANICAL equipment installation hidden dangers and solutions
原文传递
Numerical Evaluation of the Performance Enhancement of S-Shaped Diffuser at the Intake of Gas Turbine by Energy Promoters 被引量:1
19
作者 Hussain H.Al-Kayiem Raed A.Jessam +1 位作者 Sinan S.Hamdi Ali M.Tukkee 《Energy Engineering》 2025年第4期1311-1335,共25页
Size reduction of the gas turbines(GT)by reducing the inlet S-shaped diffuser length increases the powerto-weight ratio.It improves the techno-economic features of the GT by lesser fuel consumption.However,this Length... Size reduction of the gas turbines(GT)by reducing the inlet S-shaped diffuser length increases the powerto-weight ratio.It improves the techno-economic features of the GT by lesser fuel consumption.However,this Length reduction of a bare S-shaped diffuser to an aggressive S-shaped diffuser would risk flow separation and performance reduction of the diffuser and the air intake of the GT.The objective of this research is to propose and assess fitted energy promoters(EPs)to enhance the S-shaped diffuser performance by controlling and modifying the flow in the high bending zone of the diffuser.After experimental assessment,the work has been extended to cover more cases by numerical investigations on bare,bare aggressive,and aggressive with energy promoters S-shaped diffusers.Three types of EPs,namely co-rotating low-profile,co-rotating streamline sheet,and trapezoidal submerged EPs were tested with various combinations over a range of Reynolds numbers from 40,000 to 75,000.The respective S-shaped diffusers were simulated by computational fluid dynamics(CFD)using ANSYS software adopting a steady,3D,standard k-εturbulence model to acquire the details of the flow structure,which cannot be visualized in the experiment.The diffuser performance has been evaluated by the performance indicators of static pressure recovery coefficient,total pressure loss coefficient,and distortion coefficient(DC(45°)).The enhancements in the static pressure recovery of the S-shaped aggressive diffuser with energy promoters are 19.5%,22.2%,and 24.5%with EPs at planes 3,4 and 5,respectively,compared to the aggressive bare diffuser.In addition,the installation of the EPs resulted in a DC(45°)reduction at the outlet plane of the diffuser of about 43%at Re=40,000.The enhancements in the performance parameters confirm that aggravating the internal flow eliminates the flow separation and enhances the GT intake efficiency. 展开更多
关键词 Energy promoters distortion coefficient gas turbine S-shaped diffuser static pressure recovery total pressure loss
在线阅读 下载PDF
Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator
20
作者 Bin Xie Yuanhui Guo +7 位作者 Yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma Xin Chen Chingping Wong 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期378-403,共26页
With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation techno... With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation technology.Triboelectric nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this problem.As the core component of TENG,the choice of electrode materials significantly affects its performance.Traditional metal electrode materials often suffer from problems such as durability,which limits the further application of TENG.Graphene,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical properties.This review systematically summarizes the recent research progress and application prospects of TENGs based on graphene electrodes.Various precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are discussed.In addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs. 展开更多
关键词 Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor
在线阅读 下载PDF
上一页 1 2 27 下一页 到第
使用帮助 返回顶部