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Expert Experience and Data-Driven Based Hybrid Fault Diagnosis for High-SpeedWire Rod Finishing Mills 被引量:1
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作者 Cunsong Wang Ningze Tang +3 位作者 Quanling Zhang Lixin Gao Haichen Yin Hao Peng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1827-1847,共21页
The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault lo... The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault location and real-time monitoring.To solve the above problems,an expert experience and data-driven-based hybrid fault diagnosis method for high-speed wire rod finishing mills is proposed in this paper.First,based on its mechanical structure,time and frequency domain analysis are improved in fault feature extraction.The approach of combining virtual value,peak value with kurtosis value index,is adopted in time domain analysis.Speed adjustment and side frequency analysis are proposed in frequency domain analysis to obtain accurate component characteristic frequency and its corresponding sideband.Then,according to time and frequency domain characteristics,fault location based on expert experience is proposed to get an accurate fault result.Finally,the proposed method is implemented in the equipment intelligent diagnosis system.By taking an equipment fault on site,for example,the effectiveness of the proposed method is illustrated in the system. 展开更多
关键词 High-speed wire rod finishing mills expert experience DATA-DRIVEN fault diagnosis
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Lateral clavicle fracture-plating options and considerations
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作者 Sathish Muthu Saravanan Annamalai Velmurugan Kandasamy 《World Journal of Clinical Cases》 SCIE 2024年第6期1039-1044,共6页
Clavicle fractures are among the most prevalent types of fractures with numerous treatment strategies that have evolved over time.In the realm of lateral-third clavicle fracture management,several surgical methods are... Clavicle fractures are among the most prevalent types of fractures with numerous treatment strategies that have evolved over time.In the realm of lateral-third clavicle fracture management,several surgical methods are available,with plate and screw constructs being one of the most frequently employed options.Within this construct,numerous choices exist for fixing the fracture.This editorial provides an overview of the common plate options utilized in the management of distal third clavicle fractures underscoring the critical considerations and approaches that guide clinicians in selecting the most appropriate fixation techniques,considering the complex landscape of clavicle fractures and their challenging management. 展开更多
关键词 Clavicle fracture Surgical management Distal clavicle plating Superior plating Anterior plating
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Synthesis and Characterization of Nonionic Waterborne Polyurethane and Application to Wool Fabric Finishing
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作者 殷映婷 FENG Mao +1 位作者 姚金波 牛家嵘 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期497-505,共9页
A nonionic waterborne polyurethane(WPU) was synthesized by the self-emulsification method using polyether diol(N220),isophorone diisocyanate(IPDI),trimethylolpropane poly(ethylene glycol monomethyl ether)(N120),1,4-bu... A nonionic waterborne polyurethane(WPU) was synthesized by the self-emulsification method using polyether diol(N220),isophorone diisocyanate(IPDI),trimethylolpropane poly(ethylene glycol monomethyl ether)(N120),1,4-butanediol(BDO) and trimethylolpropane(TMP) as the main materials.The effects of the NCO/OH ratio on the emulsion and film properties of NWPU were explored.The experimental results show that the NWPU prepared at an NCO/OH ratio of 1.1 has good emulsion stability and easy film formation,and the resultant film was elastic,soft,and transparent.The sample was used for wool finishing and the application performance was evaluated.When the NWPU dosage reached 40 g·L^(-1),the fabric area felt shrinkage rate reduced from 8.97% to 4.75%,the pilling rating raised from grade 2-3 to grade 4,and the whiteness value only decreased by 3.87%. 展开更多
关键词 waterborne polyurethane NONIONIC wool finishing ANTI-PILLING anti-shrinking
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The principle and amelioration of lithium plating in fast-charging lithium-ion batteries
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作者 Yi Yang Xia-Lin Zhong +3 位作者 Lei Xu Zhuo-Lin Yang Chong Yan Jia-Qi Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期453-459,I0009,共8页
Fast charging is restricted primarily by the risk of lithium(Li)plating,a side reaction that can lead to the rapid capacity decay and dendrite-induced thermal runaway of lithium-ion batteries(LIBs).Investigation on th... Fast charging is restricted primarily by the risk of lithium(Li)plating,a side reaction that can lead to the rapid capacity decay and dendrite-induced thermal runaway of lithium-ion batteries(LIBs).Investigation on the intrinsic mechanism and the position of Li plating is crucial to improving the fast rechargeability and safety of LIBs.Herein,we investigate the Li plating behavior in porous electrodes under the restricted transport of Li^(+).Based on the theoretical model,it can be concluded that the Li plating on the anodeseparator interface(ASI)is thermodynamically feasible and kinetically advantageous.Meanwhile,the prior deposition of metal Li on the ASI rather than the anode-current collector interface(ACI)is verified experimentally.In order to facilitate the transfer of Li^(+)among the electrode and improve the utilization of active materials without Li plating,a bilayer asymmetric anode composed of graphite and hard carbon(GH)is proposed.Experimental and simulation results suggest that the GH hybrid electrode homogenizes the lithiated-rate throughout the electrode and outperforms the pure graphite electrode in terms of the rate performance and inhibition of Li plating.This work provides new insights into the behavior of Li plating and the rational design of electrode structure. 展开更多
关键词 GRAPHITE Hard carbon Fast charging Lithium plating Lithium-ion batteries
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Textile industry innovations in dyeing and finishing processes:Minimizing environmental impact
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《China Textile》 2024年第4期43-47,共5页
Textiles are one of the oldest industries in the world which has been manufacturing fabrics and materials needed for various purposes.However,the industry has been confronted with some problems regarding its pollution... Textiles are one of the oldest industries in the world which has been manufacturing fabrics and materials needed for various purposes.However,the industry has been confronted with some problems regarding its pollution;specifically the dyeing and finishing processes.As for the given issues,there has been a trend in recent years to come up with more environmentally friendly solutions. 展开更多
关键词 finishing DYEING IMPACT
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High-Performance 3D Li-B-C-Al Alloy Anode and its Twofold Li Electrostripping and Plating Mechanism Revealed by Synchrotron X-Ray Tomography 被引量:1
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作者 Fengcheng Tang Xia Zhang +9 位作者 Markus Osenberg Chao Yang Haifeng Huang Andr Hilger Masyuki Uesugi Kentaro Uesug Akihisa Takeuchi Ingo Manke Fu Sun Libao Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期247-256,共10页
The uncontrollable Li electrostripping and plating process that results in dendritic Li growth and huge volume change of Li anode limits the practicality of Li metal batteries(LMBs).To simultaneously address these iss... The uncontrollable Li electrostripping and plating process that results in dendritic Li growth and huge volume change of Li anode limits the practicality of Li metal batteries(LMBs).To simultaneously address these issues,designing three-dimensional(3D),lithiophilic and mechanically robust electrodes seems to be one of the cost-effective strategies.Herein,a new 3D Li-B-C-Al alloy anode is designed and fabricated.The prepared 3D alloy anode exhibits not only superior lithiophilicity that facilitates uniform Li nucleation and growth but also sufficient mechanical stability that maintains its structural integrity.Superior performance of the prepared 3D alloy is demonstrated through comprehensive electrochemical tests.In addition,non-destructive and 3D synchrotron X-ray computed tomography(SX-CT)technique is employed to investigate the underlying working mechanisms of the prepared alloy anode.A unique twofold Li electrostripping and plating mechanism under different electrochemical cycling conditions is revealed.Lastly,improved performance of the full cells built with the 3D alloy anode and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode corroborate its potential application capability.Overall,the current work not only showcases the superiority of the 3D alloy as potential anode material for LMBs but also provides fundamental insights into its underlying working mechanisms that may further propel its research and development. 展开更多
关键词 Li alloy Li metal anode Li metal battery Li-B-C-Al plating
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不同入路内固定在老年SandersⅢ型跟骨骨折中的应用及对骨折复位、疼痛介质的影响
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作者 张云峰 时晓雨 +1 位作者 王广吉 王欣 《实用手外科杂志》 2024年第2期227-230,共4页
目的对比不同入路内固定在老年SandersⅢ型跟骨骨折中的应用及对患者骨折复位、疼痛介质的影响。方法选取2019年3月-2022年9月确诊的老年SandersⅢ型跟骨骨折患者80例,依据随机数字表法分成跗骨窦组、传统组,各40例。其中传统组行L形切... 目的对比不同入路内固定在老年SandersⅢ型跟骨骨折中的应用及对患者骨折复位、疼痛介质的影响。方法选取2019年3月-2022年9月确诊的老年SandersⅢ型跟骨骨折患者80例,依据随机数字表法分成跗骨窦组、传统组,各40例。其中传统组行L形切口入路钢板内固定,跗骨窦组行跗骨窦“八”字切口入路钢板内固定。对比两组围术期指标、并发症状况、跟骨恢复效果以及围术期疼痛介质[P物质(SP)、前列腺素E2(PGE2)、5-羟色胺(5-HT)]、骨折复位状况(跟骨高度、Bohler角、Gissane角)。结果跗骨窦组住院时间与术中出血量均少于传统组(P<0.05);术后6个月,跗骨窦组、传统组跟骨恢复效果对比,差异无统计学意义(P>0.05);两组术后3个月、6个月跟骨高度、Bohler角、Gissane角均高于术前(P<0.05);跗骨窦组术后24 h、72 h血清SP、PGE2、5-HT水平均低于传统组(P<0.05);跗骨窦组并发症发生率明显低于传统组(P<0.05)。结论跗骨窦“八”字切口入路钢板内固定治疗老年SandersⅢ型跟骨骨折,可促进跟骨功能恢复,缓解术后疼痛,减少并发症发生。 展开更多
关键词 L形切口入路 跗骨窦“八”字切口入路 钢板内固定 跟骨骨折
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Optimization of Finishing Process and Energy Savings in Denim Textile Facility
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作者 Md. Enamul Haque Kaisul Kabir +5 位作者 Md. Asib Khan Mohammad Abu Syed Nizami Rajib Kabiraj Mohammed Fakhruddin Md. Golam Arif Md. Abu Hanif 《Journal of Textile Science and Technology》 2023年第3期151-164,共14页
Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing ope... Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing operations. So, several treatment processes, including enzymatic, bleaching, singeing, heat set, and ozone finish, are used, which made this processing more energy consumption and time-consuming. Therefore, it is significant to investigate how changing the chemicals and raw ingredients could improve the finishing process, which is environmentally and economically beneficial for sustainable production practices in the denim finishing process. This study’s research design comprises an experimental investigation in a denim plant in Bangladesh. Two different fabrics were chosen to analyze, determining the potential savings of finishing on the denim fabrics’ performance characteristics. By deducting singeing and heat-set processes, the researchers ran an experimental process by maintaining the same length of fabric. Then, the impacts of finishing process optimization on the mechanical, thermal, and comfort parameters of drape, stiffness, and tear strength were examined. The study’s findings demonstrated that this experiment increased productivity and reduced the finishing unit’s energy consumption without compromising the denim fabrics’ quality. This study significantly impacts environmental sustainability by preserving limited energy resources and manufacturing denim finishing processes. 展开更多
关键词 finishing Process Energy Savings Denim Fabrics Potential Savings Process Optimization Cotton-Elastane Fabric
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空心钉联合跗骨窦入路钢板固定在SandersⅡ、Ⅲ型跟骨骨折患者中的应用
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作者 刘波 《反射疗法与康复医学》 2024年第11期95-98,共4页
目的探讨空心钉联合跗骨窦入路钢板固定在SandersⅡ、Ⅲ型跟骨骨折患者中的应用。方法选取2021年1月—2023年10月新疆生产建设兵团第三师医院收治的100例SandersⅡ、Ⅲ型跟骨骨折患者为研究对象,按随机数字表法将其分为对照组和观察组,... 目的探讨空心钉联合跗骨窦入路钢板固定在SandersⅡ、Ⅲ型跟骨骨折患者中的应用。方法选取2021年1月—2023年10月新疆生产建设兵团第三师医院收治的100例SandersⅡ、Ⅲ型跟骨骨折患者为研究对象,按随机数字表法将其分为对照组和观察组,每组50例。对照组采用外侧L形入路钢板固定治疗,观察组采用空心钉联合跗骨窦入路钢板固定治疗。对比两组患者的手术情况、影像学指标、足踝功能、日常生活能力、疼痛程度、生活质量及并发症发生情况。结果观察组手术、住院时间均短于对照组,术中出血量、术后引流量均少于对照组,组间差异有统计学意义(P<0.05)。术后,观察组美国足与踝关节协会踝与后足功能评分系统评分、Barthel指数评定量表评分、世界卫生组织生活质量测定量表简表评分均高于对照组,疼痛视觉模拟评分低于对照组,组间差异有统计学意义(P<0.05)。观察组并发症发生率为4.00%,低于对照组的16.00%,差异有统计学意义(P<0.05)。两组术前、术后影像学指标对比,组间差异无统计学意义(P>0.05)。结论空心钉联合跗骨窦入路钢板固定治疗跟骨骨折的效果更佳,可减轻手术创伤,加快足踝功能恢复,减少术后并发症的发生。 展开更多
关键词 跟骨骨折 空心钉 跗骨窦入路 钢板固定 足踝功能
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Three decades and beyond:Breeding,biotech breakthroughs and future of China's GM insect-resistant cotton
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作者 Chengzhen Liang Shuangxia Jin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3243-3249,共7页
Cotton(Gossypium spp.)is a pivotal crop in the global textile industry,providing essential natural fibers.Additionally,cottonseed offers significant value as a source of oil and as feed for livestock(Huang et al.2021;... Cotton(Gossypium spp.)is a pivotal crop in the global textile industry,providing essential natural fibers.Additionally,cottonseed offers significant value as a source of oil and as feed for livestock(Huang et al.2021;Wen et al.2023).The sector,dependent on cotton,features a comprehensive value chain extending from the processing of fibers to the production of finished textiles,and it employs tens of millions of individuals(Dorward et al.1970). 展开更多
关键词 BREAKTHROUGH COTTON finished
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A Dynamic Coupling of Ocean and Plate Motion
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作者 Yongfeng Yang 《International Journal of Geosciences》 CAS 2024年第9期737-763,共27页
Plate motion representing a remarkable Earth process is widely attributed to several primary forces such as ridge push and slab pull. Recently, we have presented that the ocean water pressure against the wall of conti... Plate motion representing a remarkable Earth process is widely attributed to several primary forces such as ridge push and slab pull. Recently, we have presented that the ocean water pressure against the wall of continents may generate enormous force on continents. Continents are physically fixed on the top of the lithosphere that has been already broken into individual plates, this attachment enables the force to be laterally transferred to the lithospheric plates. In this study, we combine the force and the existing plate driving forces (i.e., ridge push, slab pull, collisional, and shearing) to account for plate motion. We show that the modelled movements for the South American, African, North American, Eurasian, Australian, Pacific plates are well agreement with the observed movements in both speed and azimuth, with a Root Mean Square Error (RMSE) of the modelled speed against the observed speed of 0.91, 3.76, 2.77, 2.31, 7.43, and 1.95 mm/yr, respectively. 展开更多
关键词 Ocean Water Pressure Force Ocean-Continent Interaction Plate Driving Force Lithospheric Plate Plate Motion
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Imaging plate scanners calibration and the attenuation behavior of imaging plate signals
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作者 薄楠 王乃彦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期38-44,共7页
Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner mode... Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner models. This method was applied to calibrate the sensitivity of a GE Typhoon FLA 7000 scanner. Additionally, we performed a calibration of the spontaneous signal attenuation behavior for BAS-MS, BAS-SR, and BAS-TR type IPs under the 20±1℃ environmental conditions, and observed significant signal carrier diffusion behavior in BAS-MS IP. The calibration results lay a foundation for further research on the interaction between ultra-short, ultra-intense lasers and matter. 展开更多
关键词 image plate SCANNER ultra-short ultra-intense lasers
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Modeling Geometrically Nonlinear FG Plates: A Fast and Accurate Alternative to IGA Method Based on Deep Learning
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作者 Se Li Tiantang Yu Tinh Quoc Bui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2793-2808,共16页
Isogeometric analysis (IGA) is known to showadvanced features compared to traditional finite element approaches.Using IGA one may accurately obtain the geometrically nonlinear bending behavior of plates with functiona... Isogeometric analysis (IGA) is known to showadvanced features compared to traditional finite element approaches.Using IGA one may accurately obtain the geometrically nonlinear bending behavior of plates with functionalgrading (FG). However, the procedure is usually complex and often is time-consuming. We thus put forward adeep learning method to model the geometrically nonlinear bending behavior of FG plates, bypassing the complexIGA simulation process. A long bidirectional short-term memory (BLSTM) recurrent neural network is trainedusing the load and gradient index as inputs and the displacement responses as outputs. The nonlinear relationshipbetween the outputs and the inputs is constructed usingmachine learning so that the displacements can be directlyestimated by the deep learning network. To provide enough training data, we use S-FSDT Von-Karman IGA andobtain the displacement responses for different loads and gradient indexes. Results show that the recognition erroris low, and demonstrate the feasibility of deep learning technique as a fast and accurate alternative to IGA formodeling the geometrically nonlinear bending behavior of FG plates. 展开更多
关键词 FG plates geometric nonlinearity deep learning BLSTM IGA S-FSDT
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A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures
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作者 Wei WEI Feng GUAN Xin FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1171-1188,共18页
A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave insulation.It consists ... A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave insulation.It consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and narrow.The bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are clarified.As experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency. 展开更多
关键词 metamaterial and metastructure vibration isolation bandgap wave insulation PLATE
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The interaction between a shaped charge jet and a single moving plate
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作者 Andreas Helte Jonas Lundgren Jonas Candle 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期1-13,共13页
Reactive armour is a very efficient add-on armour against shaped charge threats.Explosive reactive armour consists of one or several plates that are accelerated by an explosive.Similar but less violent acceleration of... Reactive armour is a very efficient add-on armour against shaped charge threats.Explosive reactive armour consists of one or several plates that are accelerated by an explosive.Similar but less violent acceleration of plates can also be achieved in a completely inert reactive armour.To be efficient against elongated jets,the motion of the plates needs to be inclined against the jet such that a sliding contact between the jet and the plates is established.This sliding contact causes a deflection and thinning of the jet.Under certain circumstances,the contact will become unstable,leading to severe disturbances on the jet.These disturbances will drastically reduce the jet penetration performance and it is therefore of interest to study the conditions that leads to an unstable contact.Previous studies on the interaction between shaped charge jets and flyer plates have shown that it is mainly the forward moving plate in an explosive reactive armour that is effective in disturbing the jet.This is usually attributed to the higher plate-to-jet mass flux ratio involved in the collision of the forward moving plate compared to the backward moving plate.For slow moving plates,as occurs in inert reactive armour,the difference in mass flux for the forward and backward moving plate is much lesser,and it is therefore of interest to study if other factors than the mass flux influences on the protection capability.In this work,experiments have been performed where a plate is accelerated along its length,interacting with a shaped charge jet that is fired at an oblique angle to the plate’s normal,either against or along the plate’s velocity.The arrangement corresponds to a jet interacting with a flyer plate from a reactive armour,with the exception that the collision velocity is the same for both types of obliquities in these experiments.The experiments show that disturbances on the jet are different in the two cases even though the collision velocities are the same.Numerical simulations of the interaction support the observation.The difference is attributed to the character of the contact pressure in the interaction region.For a backward moving plate,the maximum contact pressure is obtained at the beginning of the interaction zone and the contact pressure is therefore higher upstream than downstream of the jet while the opposite is true for a forward moving plate.A negative interface pressure gradient with respect to the jet motion results in a more stable flow than a positive,which means that the jet-plate contact is more stable for a backward moving plate than for a forward moving plate.A forward moving plate is thus more effective in disturbing the jet than a backward moving plate,not only because of the higher jet to plate mass flux ratio but also because of the character of the contact with the jet. 展开更多
关键词 Reactive armour Flyer plate Shaped charge jet
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PVDF-assisted pyrolysis strategy for corrugated plate oxygen electrocatalysis nanoreactor:Simultaneously realizing efficient active sites and rapid mass transfer
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作者 Chenxi Xu Liang Chen +6 位作者 Haihui Zhou Shifeng Qin Zhaohui Hou Yangyang Chen Jiale Sun Junwei Xu Zhongyuan Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期612-621,I0013,共11页
Though Zn-air batteries(ZABs)are one of the most promising system for energy storage and conversion,challenge still persists in its commercial application due to the sluggish kinetics of oxygen reduction/evolution rea... Though Zn-air batteries(ZABs)are one of the most promising system for energy storage and conversion,challenge still persists in its commercial application due to the sluggish kinetics of oxygen reduction/evolution reaction(ORR/OER).Hereby,a polyvinylidene fluoride(PVDF)-assisted pyrolysis strategy is proposed to develop a novel corrugated plate-like bifunctional electrocatalyst using two-dimensional zeolitic imidazolate frameworks(2D ZIF-67)as the precursor.The employed PVDF plays an important role in inheriting the original 2D structure of ZIF-67 and modulating the composition of the final products.As a result,a corrugated plate-like electrocatalyst,high-density Co nanoparticles decorated 2D Co,N,and F tri-doped carbon nanosheets,can be obtained.The acquired electrocatalyst enables efficient active sites and rapid mass transfer simultaneously,thus showing appreciable electrocatalytic performance for rechargeable Zn-air batteries.Undoubtedly,our proposed strategy offers a new perspective to the design of advanced oxygen electrocatalysts. 展开更多
关键词 Active sites Mass transfer Corrugated plate Oxygen electrocatalyst Zn-air batteries
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Analysis and optimization of stamping and forming process of bearing outer ring
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作者 Shichao Zhu Yulu Ding +4 位作者 Bing Long Hun Guo Linhan Ouyang Wengang Chen Zhengyi Jiang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期227-237,共11页
To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators suc... To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in detail.Three-dimensionalmodels of the concave and convex dies were constructed.The effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these parameters.Subsequently,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of experiments.It was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal. 展开更多
关键词 Plate stamping Bearing outer ring Mold design OPTIMIZATION
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Experimental and numerical investigations on acoustic damping of monoclinic crystalline wideband sound absorbing structures
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作者 XIE Su-chao HE Lei +3 位作者 YAN Hong-yu ZHANG Feng-yi HE Guan-di WANG Jia-cheng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1931-1944,共14页
In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the s... In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the shape of monoclinic crystals:uniaxial oblique structure(UOS)and biaxial oblique structure(BOS).Through finite element simulation and experimental research,the theoretical models of UOS and BOS were verified,and their sound absorption mechanisms were revealed.At the same time,the influence of multi-cavity composites on sound absorption performance was analyzed based on the theoretical model,and the influence of structural parameters on sound absorption performance was discussed.The research results show that,in the range of 100-2000 Hz,UOS has three sound absorption peaks and BOS has five sound absorption peaks.The frequency range of the half-absorption bandwidth(α>0.5)of UOS and BOS increases by 242% and 229%,respectively.Compared with traditional microperforated sound-absorbing structures,the series and parallel hybrid methods significantly increase the sound-absorbing bandwidth of the sound-absorbing structure.This research has guiding significance for noise control and has broad application prospects in the fields of transportation,construction,and mechanical design. 展开更多
关键词 monoclinic crystal microperforated plate acoustic metamaterials inclined cavity sound absorption
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Early Triassic Silicic Volcanics of South China:Petrogenesis and Constraints on the Geodynamic Evolution of the Paleo-Tethys Ocean Region
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作者 WANG Yabo LIU Lei +2 位作者 ZHAO Zengxia LIU Xijun HUANG Wenmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期617-629,共13页
The only occurrence of Lower Triassic silicic volcanic rocks within the South China Block is in the Qinzhou Bay area of Guangxi Province.LA-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba ... The only occurrence of Lower Triassic silicic volcanic rocks within the South China Block is in the Qinzhou Bay area of Guangxi Province.LA-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba formations formed between 248.8±1.6 and 246.5±1.3 Ma,coeval with peraluminous granites of the Qinzhou Bay Granitic Complex.The studied rhyolites and dacites are characterized by high SiO_(2),K_(2)O,and Al_(2)O_(3),and low MgO,CaO,and P_(2)O_(5) contents and are classified as high-K calc-alkaline S-type rocks,with A/CNK=0.98-1.19.The volcanic rocks are depleted in high field strength elements,e.g.,Nb,Ta,Ti,and P,and enriched in large ion lithophile elements,e.g.,Rb,K,Sr,and Ba.Although the analyzed volcanic rocks have extremely enriched zircon Hf isotopic compositions(ε_(Hf)(t)=-29.1 to-6.9),source discrimination indicators and high calculated Ti-in-zircon temperatures(798-835℃)reveal that magma derived from enriched lithospheric mantle not only provided a heat source for anatectic melting of the metasedimentary protoliths but was also an endmember component of the S-type silicic magma.The studied early Triassic volcanics are inferred to have formed immediately before closure of the Paleo-Tethys Ocean in this region,as the associated subduction would have generated an extensional setting in which the mantle-derived upwelling and volcanic activity occurred. 展开更多
关键词 GEOCHEMISTRY silicic volcanic rocks mantle contribution Olenekian-Anisian Paleo-Tethys oceanic plate subduction
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Early Treatment Outcome of Humeral Shaft Fracture Non-Union in Adults: Comparative Study of Plating versus Interlocking Nailing
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作者 Abdullallahi Bello Galadima Lukman Olalekan Ajiboye +1 位作者 Muhammad Nuhu Salihu Isha Nurudeen 《Health》 2024年第4期371-381,共11页
Background: Fractures of humeral shaft in adults are common injuries. Humeral shafts non-union either from late presentation after initial treatment by traditional bone setters or failed non-operative orthodox care is... Background: Fractures of humeral shaft in adults are common injuries. Humeral shafts non-union either from late presentation after initial treatment by traditional bone setters or failed non-operative orthodox care is a major problem in this part of the world. This non-union is a major treatment challenge with increased cost of care and morbidity in this part of the world. Humeral shaft non-union can be treated with locked intra-medullary nailing (LIMN) or dynamic compression plating (DCP). Study on comparison of these methods of fixation in this part of the world is scarce in literature search, hence the reason for this study. Objective: The objectives of this study are: (1) to compare early clinical outcome following fixation of humeral shaft fracture nonunion with DCP versus LIMN;(2) to compare the time of radiologic fracture union of DCP with LIMN;(3) to compare complications following fixation of humeral shaft fracture nonunion with DCP versus LIMN. Patients and Methods: This was a randomized control study done for 2 years in which fifty adult patients with humeral shaft non-union were recruited. The patients were grouped into 2 (P = DCP & N = LIMN). Forty five of the patients completed the follow up periods of the study and then analyzed. The P group had ORIF with DCP while the N group had ORIF with LIMN. Both groups had grafting with cancellous bones. Each patient was followed up for a period of 6 months at the time which radiographic union is expected. Any patient without clinical and/or radiographic evidence of union after six months of surgery was diagnosed as having recurrent non-union. The data generated was analyzed using SPSS Version 23. The results were presented in charts and tables. The paired t-test was used while considering p value Result: Forty five patients completed follow up. There was a male preponderance (4:1), right humerus predominated (3:2). Motor vehicular accidents were the commonest cause of the fractures (62%). Most non-union fractures occurred at the level of the middle 3<sup>rd</sup> of the humeral shaft (60%). Failed TBS treatment was the commonest indication for the osteosynthesis (71%). More patients had plating (53%) compared to 47% who had LIMN. Most patients (93.4%) had union between 3 to 6 months irrespective of fixation type with no significant statistical difference between the union rate of DCP and LIMN (p value 0.06) with similar functional outcome and complication rates irrespective of the type of fixation. Conclusion: This study showed that the success rates in term of fracture union, outcome functional grades and complication rates were not directly dependent on the types of the fixation: plating or locked intra-medullary nailing. 展开更多
关键词 Humeral Shaft NON-UNION Dynamic Compression plating Locked Intra-Medullary Nailing Early Treatment Outcome Early Outcome
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