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Mechanical reliable,NIR light-induced rapid self-healing hydrogel electrolyte towards flexible zinc-ion hybrid supercapacitors with low-temperature adaptability and long service life 被引量:1
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作者 Tengjia Gao Na Li +4 位作者 Yang Yang Jing Li Peng Ji Yunlong Zhou Jianxiong Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期63-73,共11页
Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to dras... Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ZICs.Besides,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible device.Herein,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated Sb_(2)S_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing ability.In addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 S m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 MPa with tensile elongation of 760%,together with fracture energy of 5.14 MJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illumination,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°C.Moreover,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°C.Furthermore,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°C.This contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span. 展开更多
关键词 Flexible zinc ion supercapacitor Hydrogel electrolyte self-healing Anti-freezing
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Mechanically skin-like and water-resistant self-healing bioelastomer for high-tension wound healing
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作者 Jinyi Huang Hongying Chen +7 位作者 Zenghui Jia Xingqi Song Sinan Wang Baoshuai Bai Jian Wang Junfeng Zhang Guangdong Zhou Dong Lei 《Bioactive Materials》 SCIE CSCD 2024年第9期443-455,共13页
The biomedical application of self-healing materials in wet or(under)water environments is quite challenging because the insulation and dissociation effects of water molecules significantly reduce the reconstruction o... The biomedical application of self-healing materials in wet or(under)water environments is quite challenging because the insulation and dissociation effects of water molecules significantly reduce the reconstruction of material–interface interactions.Rapid closure with uniform tension of high-tension wounds is often difficult,leading to further deterioration and scarring.Herein,a new type of thermosetting water-resistant self-healing bioelastomer(WRSHE)was designed by synergistically incorporating a stable polyglycerol sebacate(PGS)covalent crosslinking network and triple hybrid dynamic networks consisting of reversible disulfide metathesis(SS),and dimethylglyoxime urethane(Dou)and hydrogen bonds.And a resveratrol-loaded WRSHE(Res@WRSHE)was developed by a swelling,absorption,and crosslinked network locking strategy.WRSHEs exhibited skin-like mechanical properties in terms of nonlinear modulus behavior,biomimetic softness,high stretchability,and good elasticity,and they also achieved ultrafast and highly efficient self-healing in various liquid environments.For wound-healing applications of high-tension full-thickness skin defects,the convenient surface assembly by self-healing of WRSHEs provides uniform contraction stress to facilitate tight closure.Moreover,Res@WRSHEs gradually release resveratrol,which helps inflammatory response reduction,promotes blood vessel regeneration,and accelerates wound repair. 展开更多
关键词 Underwater self-healing Dynamic bonds BIOELASTOMER High-tension wounds RESVERATROL
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A Self-Healing Optoacoustic Patch with High Damage Threshold and Conversion Efficiency for Biomedical Applications
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作者 Tao Zhang Cheng-Hui Li +7 位作者 Wenbo Li Zhen Wang Zhongya Gu Jiapu Li Junru Yuan Jun Ou-Yang Xiaofei Yang Benpeng Zhu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期31-45,共15页
Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power supply.How... Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power supply.However,current optoacoustic devices remain limited due to a low damage threshold and energy conversion efficiency,which seriously hinder their widespread applications.In this study,using a self-healing polydimethylsiloxane(PDMS,Fe-Hpdca-PDMS)and carbon nanotube composite,a flexible optoacoustic patch is developed,which possesses the self-healing capability at room temperature,and can even recover from damage induced by cutting or laser irradiation.Moreover,this patch can generate high-intensity ultrasound(>25 MPa)without the focusing structure.The laser damage threshold is greater than 183.44 mJ cm^(-2),and the optoacoustic energy conversion efficiency reaches a major achievement at 10.66×10^(-3),compared with other carbon-based nanomaterials and PDMS composites.This patch is also been successfully examined in the application of acoustic flow,thrombolysis,and wireless energy harvesting.All findings in this study provides new insight into designing and fabricating of novel ultrasound devices for biomedical applications. 展开更多
关键词 Optoacoustic self-healing PDMS Acoustic flow THROMBOLYTIC Wireless energy harvesting
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Flexible,thermal processable,self-healing,and fully bio-based starch plastics by constructing dynamic imine network
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作者 Xiaoqian Zhang Haishan Zhang +2 位作者 Guowen Zhou Zhiping Su Xiaohui Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1610-1618,共9页
The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and ... The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and renewable nature.However,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread application.To overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions.This strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature(T_(g)=20.15℃).Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility(elongation at break=45.2%)and waterproof capability(water contact angle=109.2°).Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical degradability.This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics. 展开更多
关键词 Bioplastic Covalent adaptable networks Schiff base chemistry Thermal processability self-healing
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Multifunctional phase change film with high recyclability, adjustable thermal responsiveness, and intrinsic self-healing ability for thermal energy storage
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作者 Bo Yang Xuelai Zhang +2 位作者 Jun Ji Weisan Hua Miaomiao Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期216-227,I0005,共13页
Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,whic... Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,which does not meet the growing demand for multi-functional materials.In this paper,the flexible material and hydrogen-bonding function are innovatively combined to design and prepare a novel multi-functional flexible phase change film(PPL).The 0.2PPL-2 film exhibits solid-solid phase change behavior with energy storage density of 131.8 J/g at the transition temperature of42.1℃,thermal cycling stability(500 cycles),wide-temperature range flexibility(0-60℃) and selfhealing property.Notably,the PPL film can be recycled up to 98.5% by intrinsic remodeling.Moreover,the PPL film can be tailored to the desired colors and configurations and can be cleverly assembled on several thermal management systems at ambient temperature through its flexibility combined with shape-memory properties.More interestingly,the transmittance of PPL will be altered when the ambient temperature changes(60℃),conveying a clear thermal signal.Finally,the thermal energy storage performance of the PPL film is successfully tested by human thermotherapy and electronic device temperature control experiments.The proposed functional integration strategy provides innovative ideas to design PCMs for multifunctionality,and makes significant contributions in green chemistry,highefficiency thermal management,and energy sustainability. 展开更多
关键词 Phase change film Multifunctional material Energy storage self-healing RECYCLABILITY
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Shear resistance of assembled bentonite interface after confined water saturation and interfacial self-healing capacity
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作者 Xinxin Dong Yonggui Chen +2 位作者 Xiaohua Bao Weimin Ye Qiong Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4742-4753,共12页
The requisite functions of a bentonite buffer in a deep geological repository depend on the sealing/healing of bentonite interfaces,with particular emphasis on the self-healing(automatic healing upon wetting)of assemb... The requisite functions of a bentonite buffer in a deep geological repository depend on the sealing/healing of bentonite interfaces,with particular emphasis on the self-healing(automatic healing upon wetting)of assembled bentonite-bentonite interfaces.This study determined the shear resistance(including the peak shear strength and secant modulus)of densely compacted Gaomiaozi(GMZ)bentonite and its assembled interface after confined water saturation.The effect of bentonite dry density and saturation time on the shear resistance of saturated healed interfaces was elucidated,and the interfacial self-healing capacity was assessed.The results indicate that the shear resistance of the saturated healed interfaces increased with the bentonite dry density but had a non-monotonic correlation with the saturation time.For a given dry density of the bentonite,the saturated healed interface exhibits a lower peak shear strength than the saturated intact bentonite but a higher peak shear strength than the saturated separated interface.The saturated healed and separated interfaces have comparable shear moduli(secant moduli),which are lower than that of the saturated intact bentonite.The saturated healed interfaces display smooth shear failure planes,while the saturated assembled interfaces and intact bentonite exhibit comparable frictional angles.This indicates that interfacial self-healing plays a pivotal role in enhancing interfacial peak shear strength by facilitating microstructural bonding at the assembled interface.Finally,it can be stated that densely compacted GMZ bentonite has a robust interfacial self-healing capacity in terms of shear resistance.These findings contribute to the design of the bentonite buffer and facilitate the evaluation of its safe operation at specified disposal ages. 展开更多
关键词 Compacted bentonite INTERFACE self-healing Peak shear strength Shear modulus
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High performance photodegradation resistant PVA@TiO_(2)/carboxyl-PES self-healing reactive ultrafiltration membrane
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作者 Yu Liang Yuanfang Fan +5 位作者 Zhongmin Su Mingxin Huo Xia Yang Hongliang Huo Chi Wang Zhi Geng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期31-39,共9页
The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Never... The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes. 展开更多
关键词 Ultrafiltration membrane SELF-CLEANING self-healing Poly(aryl ether sulfone)
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An intrinsically self-healing and anti-freezing molecular chains induced polyacrylamide-based hydrogel electrolytes for zinc manganese dioxide batteries
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作者 Haiyang Liao Wenzhao Zhong +8 位作者 Chen Li Jieling Han Xiao Sun Xinhui Xia Ting Li Abolhassan Noori Mir F.Mousavi Xin Liu Yongqi Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期565-578,I0013,共15页
The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self... The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service conditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84%capacity retention at-20℃)and intrinsic self-healing capabilities(95%capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc||manganese dioxide cell an economically feasible battery for the state-of-the-art applications.The Zn||AF/SH-Hydrogel||MnO_(2)device offers a near-theoretical specific capacity of 285 m A h g^(-1)at 0.1 A g^(-1)(Coulombic efficiency≈100%),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel electrolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices. 展开更多
关键词 Flexible aqueous battery Hydrogel electrolyte ANTI-FREEZING self-healing Dual-dynamic reversible bond
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Feedback linearization and equivalent-disturbance compensation control strategy for piezoelectric stage
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作者 Tao Huang Yingbin Wang +3 位作者 Zhihong Luo Huajun Cao Guibao Tao Mingxiang Ling 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期49-59,共11页
Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used ... Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning fields.However,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric stage.Inspired by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric stage.In particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis nonlinearity.In addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external disturbances.An analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the laboratory.The experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance. 展开更多
关键词 Piezoelectric stage Hysteresis nonlinearity Feedback linearization Equivalent-disturbance compensation
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Effect of drying cracks on swelling and self-healing of bentonite-sand blocks used as engineered barriers for radioactive waste disposal
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作者 Yu Tan Guangping Zhou +2 位作者 Huyuan Zhang Xiaoya Li Ping Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1776-1787,共12页
Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to... Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste repository.Synthetic groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for China's repository.Healing of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried blocks.The results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying cracks.The maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh blocks.The maximum swelling pressure measured in strong(i.e.high ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI water.Nevertheless,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT images.The hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks. 展开更多
关键词 Beishan groundwater chemistry Bentonite buffer Drying cracks High-level radioactive waste(HLW) self-healing SWELLING
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Trajectory compensation for multi-robot coordinated lifting system considering elastic catenary of the rope
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作者 ZHAO Xiangtang ZHAO Zhigang +2 位作者 SU Cheng MENG Jiadong WANG Baoxi 《High Technology Letters》 EI CAS 2024年第3期252-262,共11页
The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the... The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the kinematic and dynamic analysis of the lifting system,the elastic catenary mod-el considering the elasticity and mass of the flexible rope is established,and the effect of the deform-ation of the flexible rope on the position and posture of the suspended object is analyzed.According to the deformation of flexible rope,a real-time trajectory compensation method is proposed based on the compensation principle of position and posture.Under the lifting task of the low-speed move-ment,this is compared with that of the system which neglects the deformation of the flexible rope.The trajectoy of the lifting system considering the deformation of flexible rope.The results show that the mass and elasticity of the flexible rope can not be neglected.Meanwhile,the proposed trajectory compensation method can improve the movement accuracy of the lifting system,which verifies the ef-fectiveness of this compensation method.The research results provide the basis for trajectory plan-ning and coordinated control of the lifting system。 展开更多
关键词 multi-robot lifting system deformation of flexible rope elastic catenary model compensation principle of position and posture trajectory compensation
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Case study on the mechanics of NPR anchor cable compensation for large deformation tunnel in soft rock in the Transverse Mountain area,China
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作者 LI Yong ZHENG Jing +3 位作者 HUO Shu-sen WANG Feng-nian HE Man-chao TAO Zhi-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2054-2069,共16页
A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced duri... A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel construction.To mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio effect.Physical model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables.The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the tunnel.Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 mm.This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas. 展开更多
关键词 soft rock large deformation NPR anchor cable physical model numerical simulation compensation mechanics
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Microstructure and properties of 35 kg large aluminum alloy flywheel housing components formed by squeeze casting with local pressure compensation
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作者 Ju-fu Jiang Jing Yan +4 位作者 Ying-ze Liu Ning Ge Ying Wang Chang-jie Ding De-chao Zou 《China Foundry》 SCIE EI CAS CSCD 2024年第5期563-576,共14页
The squeeze casting method with local pressure compensation was proposed to form a flywheel housing component with a weight of 35 kg.The numerical simulation,microstructure observation and phase characterization were ... The squeeze casting method with local pressure compensation was proposed to form a flywheel housing component with a weight of 35 kg.The numerical simulation,microstructure observation and phase characterization were performed,and the influence of local pressure compensation on feeding of thick-wall position,microstructure and mechanical properties of the formed components were discussed.Results show that the molten metal keeps a good fluidity and the filling is complete during the filling process.Although the solidification at thick-wall positions of the mounting ports is slow,the local pressure compensation effectively realizes the local forced feeding,significantly eliminating the shrinkage cavity defects.In the microstructure of AlSi9Mg alloy,α-Al primarily consists of fragmented dendrites and rosette grains,while eutectic Si predominantly comprises needles and short rods.The impact of local pressure compensation on strength is relatively minimal,yet its influence on elongation is considerable.Following local pressure compensation,the average elongation at the compensated areas is 9.18%,which represents a 44.90%higher than that before compensation.The average tensile strength is 209.1 MPa,and the average yield strength is 100.6 MPa.The local pressure compensation can significantly reduce or even eliminate the internal defects in the 35 kg large-weight components formed by squeeze casting. 展开更多
关键词 squeeze casting local pressure compensation aluminum alloy microstructure mechanical properties large flywheel housing components
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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation
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作者 You-Ming Deng Yong-Bin Leng +2 位作者 Xing-Yi Xu Jian Chen Yi-Mei Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期99-108,共10页
Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal re... Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter measurements.Therefore,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this paper.Compared with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed signal.The basic principles of the method,simulation,and experimental comparison are also introduced.Based on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal oscillation.The results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed. 展开更多
关键词 Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF
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Research on Anti-Fluctuation Control of Winding Tension System Based on Feedforward Compensation
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作者 Yujie Duan Jianguo Liang +4 位作者 Jianglin Liu Haifeng Gao Yinhui Li Jinzhu Zhang Xinyu Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1239-1261,共23页
In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tens... In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations. 展开更多
关键词 Constant tension control anti-fluctuation strategy tension fluctuation observer time-varying parameters fractional-order PID controller feedforward compensate
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Study on thermal decomposition kinetics of azobenzene-4,4′-dicarboxylic acid by using compensation parameter method and nonlinear fitting evaluation
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作者 Shuyi Shen Song Guo +1 位作者 Sining Chen Jinhua Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期269-279,共11页
Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application ... Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained. 展开更多
关键词 Azobenzene-4 4′-dicarboxylic acid Thermal decomposition behavior Kinetic mechanism Thermal hazard evaluation compensation parameter effect
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Excavation compensation and bolt support for a deep mine drift
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作者 Longji Guo Zhigang Tao +1 位作者 Manchao He Massimo Coli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3206-3220,共15页
To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 13... To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 130 KN was developed.In the conducted tests,the amount of deformation was 200-2000 mm,the breaking force reached 350 KN,and a high constant-resistance pre-stress was maintained during the deformation process.A stress compensation theory of phosphate rock excavation based on NPR bolts is proposed together with a balance system for bolt compensation of the time-space effect and high NPR pre-stress.Traditional split-set rock bolts are unable to maintain the stability of roadway roofs and pillars.To verify the support effect of the proposed bolt,field tests were conducted using both the proposed NPR bolts and split-set rock bolts as support systems on the same mining face.In addition,the stress compensation mechanism of roadway mining was simulated using the particle flow code in three dimensions(PFC^(3D))-fast Lagrangian analysis of continua(FLAC^(3D))particle-flow coupling numerical model.On-site monitoring and numerical simulations showed that the NPR excavation compensation support scheme effectively improves the stress state of the bolts and reduces the deformation of the surrounding rock.Compared to the original support scheme,the final deformation of the surrounding rock was reduced by approximately 70%.These results significantly contribute to domestic and foreign research on phosphate-rock NPR compensation support technology,theoretical systems,and engineering practices,and further promote technological innovation in the phosphate rock mining industry. 展开更多
关键词 Deep phosphate rock NPR bolt Split-set rock bolt PFC3D-FLAC3D compensation support
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A frequency domain estimation and compensation method for system synchronization parameters of distributed-HFSWR
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作者 WANG Hongyong SUO Ying +3 位作者 DENG Weibo WU Xiaochuan BAI Yang ZHANG Xin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1084-1097,共14页
To analyze the influence of time synchronization error,phase synchronization error,frequency synchronization error,internal delay of the transceiver system,and range error and angle error between the unit radars on th... To analyze the influence of time synchronization error,phase synchronization error,frequency synchronization error,internal delay of the transceiver system,and range error and angle error between the unit radars on the target detection performance,firstly,a spatial detection model of distributed high-frequency surface wave radar(distributed-HFSWR)is established in this paper.In this model,a method for accurate extraction of direct wave spectrum based on curve fitting is proposed to obtain accurate system internal delay and frequency synchronization error under complex electromagnetic environment background and low signal to noise ratio(SNR),and to compensate for the shift of range and Doppler frequency caused by time-frequency synchronization error.The direct wave component is extracted from the spectrum,the range estimation error and Doppler estimation error are reduced by the method of curve fitting,and the fitting accuracy of the parameters is improved.Then,the influence of frequency synchronization error on target range and radial Doppler velocity is quantitatively analyzed.The relationship between frequency synchronization error and radial Doppler velocity shift and range shift is given.Finally,the system synchronization parameters of the trial distributed-HFSWR are obtained by the proposed spectrum extraction method based on curve fitting,the experimental data is compensated to correct the shift of the target,and finally the correct target parameter information is obtained.Simulations and experimental results demonstrate the superiority and correctness of the proposed method,theoretical derivation and detection model proposed in this paper. 展开更多
关键词 distributed high-frequency surface wave radar(distributed-HFSWR) direct wave synchronization error curve fitting system synchronization parameter compensation
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Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC
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作者 Kaixian Ba Yuan Wang +4 位作者 Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期228-246,共19页
Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhi... Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot. 展开更多
关键词 Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)
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The Rights to Claim for Industrial Injury Compensation and Tort Compensation are Applicable to the Law:Taking Fu and Li v.a Passenger Transport Company as an Example
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作者 Li Guo 《Journal of Contemporary Educational Research》 2024年第1期154-158,共5页
In the case of third-party tort,due to the lack of clear and detailed provisions on the treatment of employee’s industrial injury insurance payment and tort damage compensation,the judicial theory and practice have b... In the case of third-party tort,due to the lack of clear and detailed provisions on the treatment of employee’s industrial injury insurance payment and tort damage compensation,the judicial theory and practice have brought many disputes.Through combing the current relevant laws and regulations,it can be found that the application of the two systems will lead to the overlapping of industrial injury compensation.This paper analyzes the problems arising from the concurrence of industrial injury compensation and tort compensation using the case of Fu and Li v.a passenger transport company,and puts forward some ideas and suggestions on how to improve the settlement measures of such cases. 展开更多
关键词 Industrial injury compensation and tort compensation Double indemnity
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