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Optimal Design of Energy Saving for Filament and Dust Removal System in Cigarette Factory
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作者 HUANGXinliang DUWenhao KONGJian 《外文科技期刊数据库(文摘版)工程技术》 2022年第12期055-059,共5页
In the silk-making workshop of a cigarette factory, dust problems will inevitably occur during the processing of tobacco leaves. Generally, each silk-making dust-removing and package dust-removing outlet has a corresp... In the silk-making workshop of a cigarette factory, dust problems will inevitably occur during the processing of tobacco leaves. Generally, each silk-making dust-removing and package dust-removing outlet has a corresponding air suction port to absorb the dust and then centrally treat it. In the past, due to large-scale centralized production, the correlation between equipment was relatively high, and there was basically no no-load situation. In recent years, due to flexible production and group processing technology, even if a production line is used, there is an uneven production load, and no-load energy consumption. The situation is more prominent. Using hardware equipment such as solenoid valves, cylinders, and wind speed sensors, combined with PLC communication and control technology, energy-saving transformation of the dust removal system is simple, low cost, and effective, and can solve the problem of no-load energy consumption of the dust removal system. 展开更多
关键词 cigarette factory silk-making dust removal system system energy-saving design
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RESEARCH ON PROTECTION OF STEEL PILES OF BAOSHAN GENERAL STEEL FACTORY WHARF BY USING DZ AND DZ-2 TAPES
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作者 戴钟道 倪湘毓 +1 位作者 夏庚美 袁理 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1989年第4期355-359,387,共6页
Steel piles at the tidal zone can be seriously corroded. Common protective methods such as painting or coating with rubber or other protective materials, etc. cannot provide full protection when used as supplementary ... Steel piles at the tidal zone can be seriously corroded. Common protective methods such as painting or coating with rubber or other protective materials, etc. cannot provide full protection when used as supplementary protection because these traditional methods require strict pretreatment and sealing of the metallic surface from the corrosive mediums.and time for the protective coatings to solidify. This is very difficult under the severe action of waves and surges on the sea.With our oil-soluble DZ-2 tape, protection efficiency for hanging steel plates at the tidal and splash zones reaches to 82-99%. The protection efficiency of water soluble DZ tape at the tidal zone reaches to 92.9%. The DZ and DZ-2 tapes can rapidly reduce the original corrosion velocity to ten percent and one percent respectively as fully proved by the 500 hour rapid corrosion testing with indoor salt fog and by the relevant electrochemical parameters of instantaneous corrosion velocity,etc.DZ tape absorbs much OH- to cause a pH 展开更多
关键词 tidal HANGING protective pretreatment painting seriously rubber sealing metallic PILES
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A new technology for harnessing the dye polluted water and dye collection in a chemical factory
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作者 PU Jiang-ping PU Pei-min +3 位作者 HU Chun-hua QIAN Jun-long PU Ju-xing HUA Ji-kang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期198-200,共3页
A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat-electric energy. It ... A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat-electric energy. It consists of four parts: (1) evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2)polluted water circulating system (pumping-spraying-collecting); (3)heating system; (4)workshop with polluted water reservoir-tanks and rainfall prevention roof. The polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind and air temperature energy). In case, when there is no roof for the carrier system, the polluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10-25 mm rainfall also need to be stored in the reservoirs to meet the state standard or discharging wastewater. The dye may be collected at the surface in the reservoir-tanks and the crystallized salt may be collected at the bottom plate. The black-color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non-pollution production of dye may be realized by using this technology with environmental, economical and social benefits. 展开更多
关键词 dye polluted water harnessing dye collection technology
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Evaluation on the Influencing Factors of Shutdown of ZJ17 Reel Equipment in a Cigarette Factory —— Based on Analytic Hierarchy Process
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作者 LIU Ying GU Junwen ZHENG Mingming 《外文科技期刊数据库(文摘版)工程技术》 2021年第7期147-151,共9页
The application of the analytic hierarchy process (AHP), combined with a ZJ17 cigarette factories wrap workshop equipment management actual volume, respectively, from the personnel factor, equipment factor, material f... The application of the analytic hierarchy process (AHP), combined with a ZJ17 cigarette factories wrap workshop equipment management actual volume, respectively, from the personnel factor, equipment factor, material factor, environmental factors four aspects carries on the analysis, determine the nine main impact indicators, from nine indicators for ZJ17 volume effect the equipment downtime of main influence factors for evaluation. According to the decision goal, the evaluation model is established, the comparative judgment matrix is constructed, the weight coefficient of each index is calculated, the consistency test is carried out, and the evaluation result is finally obtained. Based on the evaluation results, countermeasures and suggestions are put forward: focusing on strengthening the shutdown control system, strengthening equipment spot inspection, and attaching importance to the training of staff work experience. 展开更多
关键词 wrap workshop ZJ17 analytic hierarchy process weight coefficient
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Emei Semiconductor Material Factory
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作者 李本成 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1991年第1期68-69,共2页
Emei Semiconductor Material Factoryincluding Emei Research Institute ofSemiconductor Material is an importantcomplex unit combining factory with insti-tute specialized in production,trial-produc-tion and scientific re... Emei Semiconductor Material Factoryincluding Emei Research Institute ofSemiconductor Material is an importantcomplex unit combining factory with insti-tute specialized in production,trial-produc-tion and scientific research of semiconductormaterials in China.It is not only a key en-terprise in China National Nonferrous Met-als Industry Corporation,but also an im- 展开更多
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Phase-field simulation of the dendrite fragmentation by electromagnetic stirring in AA5754 aluminum alloy laser beam welding
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作者 Chunliang Yang Fan Yang +3 位作者 Xiangmeng Meng Stephen Nugraha Putra Marcel Bachmann Michael Rethmeier 《China Welding》 2026年第1期57-68,共12页
A phase-field model including magnetic field induced dendrite fragmentation was established and applied to the cases with different initial crystal nuclear positions for AA5754 aluminum alloy electromagnetic laser bea... A phase-field model including magnetic field induced dendrite fragmentation was established and applied to the cases with different initial crystal nuclear positions for AA5754 aluminum alloy electromagnetic laser beam welding.Compare the calculated results that include dendrite fragmentation caused by the thermal electromagnetic Lorentz force with the results that consider only the thermal electromagnetic Lorentz force,without fragmentation,at the characteristic time instants.Both in the early and late stages,the small fragmentation at the dendrite tip promotes the number of higher-order branches and their growth,especially in the direction perpendicular to the solidification.The later stage fragmentation has the possibility of breaking one grain into several,which verifies the possibility of grain refinement caused by dendrite fragmentation.The fracture surface caused by fragmentation also makes more solid-liquid interfaces and their growth.In addition,the cases with different initial nuclear positions were compared.The grain growth in the low-temperature zone can be inhibited by the equiaxed grains'fragmentation at the high-temperature area(179.8μm^(2) and 14.7% start at the center,115.4μm^(2) and 9.4% start at the high-temperature corner,134.3μm^(2) and 10.9%start at the low-temperature corner),which is another kind of grain refinement by the dendrite fragmentation.This kind of inhibition effect on grain growth in the low-temperature region will be enhanced with the increasing time interval between the two crystal nuclei’appearance(179.8μm^(2) and 14.7%when virtual grains appear at t=4.3803 s and t=4.3803 s,134.3μm^(2) and 10.9%at t=4.0977 s and t=3.9564 s,and 115.4μm^(2) and 9.4%at t=3.8151 s and t=3.5325 s). 展开更多
关键词 Laser beam welding ELECTROMAGNETIC Aluminum alloys Phase field method Equiaxed grain Dendrite fragmentation
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Structural Reliability Analysis Based on Differential Evolution Algorithm and Hypersphere Integration
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作者 CHEN Zhenzhong HAN Zhuo +4 位作者 WANG Peiyu PAN Qianghua LI Xiaoke GAN Xuehui CHEN Ge 《Journal of Donghua University(English Edition)》 2026年第1期118-130,共13页
In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order relia... In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision. 展开更多
关键词 reliability analysis design point positioning differential evolution algorithm hypersphere integration
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Effects of modulation layer thickness on microstructures and mechanical behavior of VN/TiN−Ni nano-multilayered films
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作者 Wen-jie CHENG Ping LIU +4 位作者 Xin-fa ZHU Yi MENG Hong-mei LU Peter K.LIAW Wei LI 《Transactions of Nonferrous Metals Society of China》 2026年第2期586-599,共14页
The dependence of interface structure and mechanical properties on the modulation layer thickness of VN/TiN−Ni nano-multilayered films deposited on Si substrates using a reactive magnetron sputtering technique was sys... The dependence of interface structure and mechanical properties on the modulation layer thickness of VN/TiN−Ni nano-multilayered films deposited on Si substrates using a reactive magnetron sputtering technique was systematically investigated. The films were characterized using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, and nanoindentation. The results show that the TiN−Ni layer grows epitaxially on the VN layer, forming a coherent interface between the two sublayers. When the deposition time ratio of the two sublayers (TTiN−Ni꞉TVN) is 10꞉12, the films exhibit remarkable mechanical properties, with hardness, elastic modulus, and fracture toughness values of 25.9 GPa, 317 GPa, and 1.88 MPa·m^(1/2), respectively. Meanwhile, fracture toughness is improved by approximately 50% compared to the VN monolithic film. This enhancement is attributed to the coherent interface between the sublayers and the phase separation in the TiN−Ni layer. 展开更多
关键词 nano-multilayered film modulation-layer thickness phase separation strengthening fracture toughness
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Low-polarity solvent-mediated lithium metal stabilization for improved performance in lithium–sulfur batteries
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作者 Seung-Yeon Jung Yao-Peng Chen +4 位作者 Yun-Jeong Lee So Hee Kim Jong-Seong Bae Xiang Chen Seung-Ho Yu 《Journal of Energy Chemistry》 2026年第3期737-749,共13页
Rechargeable lithium–sulfur(Li–S)batteries are considered promising next-generation energy storage systems owing to their high theoretical energy density,but their application is hindered by the shuttle effect arisi... Rechargeable lithium–sulfur(Li–S)batteries are considered promising next-generation energy storage systems owing to their high theoretical energy density,but their application is hindered by the shuttle effect arising from dissolved lithium polysulfides(LiPSs).Herein,we design an optimized electrolyte to achieve long-term stability by employing an appropriate low-polarity solvent.A combination of diethyl ether(DEE)and 1,2-dimethoxyethane(DME)was selected to improve Li metal stability even in the presence of LiPSs.The DEE/DME electrolyte not only suppresses parasitic reactions between Li and LiPSs but also promotes uniform Li deposition.Moreover,operando optical microscopy was employed to directly visualize electrolyte stability and dendrite evolution in real time,while quantitative analysis was conducted via normalized hue index and contour image mapping.The enhanced anode stability of the DEE/DME electrolyte enabled excellent cycling performance,retaining 80.14%of its initial capacity after300 cycles at 3 C,while maintaining superior performance under practical conditions with high sulfur loading and a low E/S ratio.These findings highlight that solvent properties critically influence Li metal stabilization in Li–S batteries and underscore the significance of solvent engineering in electrolyte design. 展开更多
关键词 Li–S batteries Electrolyte engineering Solvent polarity Solvent effects Anode stabilization Operando optical microscopy
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Revealing the mechanisms behind transient whisker suppression by LiNO_(3) in anode-free lithium metal batteries
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作者 Seokho Nahm Hyunbin Kim +14 位作者 Mihyun Kim Kwanyoung Oh Haena Yim Somi Lee Jinseok Hong Minki Kim Jeongmin Kim Yoon Kyung Seo Yun Chang Park Jong Min Yuk Chong-Seung Yoon Ji-Won Choi Nuri Oh Seung-Ho Yu Seung-Yong Lee 《Journal of Energy Chemistry》 2026年第3期485-495,共11页
The electrolyte additive,lithium nitrate(LiNO_(3)),is widely recognized for suppressing dendritic lithium growth in anode-free lithium metal batteries,yet its stabilizing effect is transient,and the mechanistic origin... The electrolyte additive,lithium nitrate(LiNO_(3)),is widely recognized for suppressing dendritic lithium growth in anode-free lithium metal batteries,yet its stabilizing effect is transient,and the mechanistic origin of this limitation has remained unresolved.Here,we uncover the origin of this behavior through a comprehensive analysis driven by artifact/damage-free direct cryogenic transmission electron microscopy,which enabled one of the most chemically specific and morphologically intuitive visualizations to date of intact solid-electrolyte interphases(SEIs)and lithium growth.Contrary to conventional interpretations centered on nitrogen-rich or single-component SEIs,we reveal that LiNO_(3) rapidly generates lithium hydroxide(LiOH)and lithium oxide(Li_(2)O)rich interphases,whose complementary functions—ionic transport through LiOH and mechanical robustness from Li_(2)O—synergistically suppress whisker nucleation and favor compact,particle-like growth.Over the extended plating,however,depletion of these species in combination with crystallographically favored orientations drives the particle-towhisker transition,explaining why the effectiveness of LiNO_(3) is inherently limited.This direct mechanistic visualization resolves a long-standing ambiguity regarding the transient efficacy of LiNO_(3) and reframes its function from a nitrogen-driven mechanism to a synergistic dual oxygen-interphase framework.Beyond mechanistic clarification,these findings establish that continuous regeneration of LiOH and Li_(2)O is essential for stable lithium deposition,offering a design principle for the development of durable electrolytes in high-performance anode-free lithium metal batteries. 展开更多
关键词 Anode-free lithium metal battery LiNO_(3)electrolyte additive Lithium whisker suppression Air-free cryo-TEM LiOH/Li_(2)O SEI
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Microstructure characteristics and corrosion behavior of metal inert gas welded dissimilar joints of 6005A modified by Sc and 5083 alloys 被引量:3
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作者 Guo-fu XU Liang LIU +7 位作者 Ying DENG Yu ZENG Jun-chang CAO Lei TANG Xiao-yan PENG Jia-qi DUAN Mei-chan LIANG Qing-lin PAN 《Transactions of Nonferrous Metals Society of China》 2025年第1期60-76,共17页
The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion... The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion tests and microscopy techniques.Results show that the dissimilar joints exhibit strong stress corrosion cracking(SCC)resistance,maintaining substantial strength during slow strain rate tensile tests.Notably,the heat-affected zone(HAZ)and base metal(BM)on the 6005A+Sc side show superior performance in terms of inter-granular corrosion(IGC)and exfoliation corrosion(EXCO)compared to the corresponding zones on the 5083 side.The lower corrosion resistance of the 5083-BM and the 5083-HAZ can be attributed to the presence of numerous Al_(2)Mg_(3)phases and micro-scaled Al_(6)(Mn,Fe)intermetallics,mainly distributed along the rolling direction.Conversely,the enhanced corrosion resistance of the 6005A+Sc-BM and the 6005A+Sc-HAZ can be attributed to the discontinuously distributed grain boundary precipitates(β-Mg_(2)Si),the smaller grain size,and the reduced corrosive current density. 展开更多
关键词 metal inert gas welding dissimilar joint aluminum alloy corrosion microstructure
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Experimental Acoustic Analysis of Cavitation in a Centrifugal Pump
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作者 Dongwei Wang Wensheng Ma +2 位作者 Weiguo Zhao Rui Cao Youchao Yang 《Fluid Dynamics & Materials Processing》 2025年第4期877-890,共14页
Cavitation is an unavoidable phenomenon in the operation of centrifugal pumps.Prolonged cavitation can cause significant damage to the components of the flow channel,and in severe cases,it may even interfere with the ... Cavitation is an unavoidable phenomenon in the operation of centrifugal pumps.Prolonged cavitation can cause significant damage to the components of the flow channel,and in severe cases,it may even interfere with the normal energy exchange processes within the pump.Therefore,effective monitoring of cavitation in centrifugal pumps is crucial.This article presents a study that approaches the issue from an acoustic perspective,using experimental methods to gather and analyze acoustic data at the inlet and outlet of centrifugal pumps across various flow rates,with hydrophones as the primary measuring instruments.Results show that flow rate significantly affects noise levels in both non-cavitation and mild cavitation stages,with noise increasing as the flow rate rises.As the cavitation margin(NPSHa)decreases,inlet and outlet noise trends diverge:inlet noise drops sharply,while outlet noise initially increases before sharply decreasing.Both exhibit a distinct zone of abrupt change,where NPSHa values offer earlier cavitation detection than traditional methods.The noise at the pump’s inlet and outlet primarily consists of discrete and broadband noise,with most energy concentrated at discrete frequencies—shaft frequency(24 Hz),blade frequency(144 Hz),and their harmonics.As NPSHa decreases,the inlet’s discrete and broadband noise frequencies decline,while they increase at the outlet.Monitoring changes in these spectrum characteristics provides an additional means of predicting cavitation onset. 展开更多
关键词 Centrifugal pump CAVITATION EXPERIMENT cavitation noise frequency spectrum
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Effect of Heat Treatment on Microstructure Evolution and Fracture Mechanism of 30CrMo/316L Multilayered Composites Fabricated by Vacuum Electron Beam Welding and Accumulative Hot Roll Bonding
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作者 Ming-Rong Fan Tian-Yu Wang +3 位作者 Jing-Gang Suo Ming-Kun Wang Ying-Ying Feng Zong-An Luo 《Acta Metallurgica Sinica(English Letters)》 2025年第12期2265-2278,共14页
The effects of accumulative hot rolling followed by solution treatment on the microstructural evolution and fracture behavior of 30CrMo/316L multilayered composites have been investigated.A scanning electron microscop... The effects of accumulative hot rolling followed by solution treatment on the microstructural evolution and fracture behavior of 30CrMo/316L multilayered composites have been investigated.A scanning electron microscope equipped with an electron backscatter diffraction probe,a laser confocal microscope,an electron probe microanalysis,and a universal testing machine were employed to characterize the microstructures and mechanical properties.The results indicate that solution treatment transformed the microstructure of the 30CrMo layer from ferrite to martensite,while the 316L layer remained austenitic but transitioned from the rolled to the recrystallized state.Additionally,solution treatment significantly enhanced the mechanical properties of the composite,leading to an increase in yield strength and ultimate tensile strength to 744 and 1106 MPa,respectively—258 and 276 MPa higher than those of the hot-rolled plate.The enhancement in strength is primarily attributed to the formation of high-strength martensite in the 30CrMo layer.During deformation,the composite interface effectively impeded crack propagation and induced step-like deflection.However,the formation of cross-layer grains facilitated crack nucleation at grain boundaries,leading to rapid crack propagation and instantaneous fracture.Therefore,preventing the formation of cross-layer grains during the heat treatment process is crucial,as their presence weakens the interfacial strengthening effect of the composite plate.This study provides valuable insights for the design and development of multi-layered steels. 展开更多
关键词 30CrMo/316L multilayered composite Accumulative rolling Solution treatment Microstructural evolution Fracture mechanism
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Unveiling anomalous strengthening and deformation mechanism evolution in a Mg-Gd-Y-Zr alloy under rate-temperature coupling effects
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作者 Jingli Li Chen Wen Xiuzhu Han 《Journal of Magnesium and Alloys》 2025年第6期2913-2926,共14页
While the deformation behavior of rare-earth magnesium alloys at high temperatures has been extensively studied,the deformation mechanisms under moderate-to-low temperatures and high strain rates remain insufficiently... While the deformation behavior of rare-earth magnesium alloys at high temperatures has been extensively studied,the deformation mechanisms under moderate-to-low temperatures and high strain rates remain insufficiently understood.To address this gap,hot compression tests were conducted on a Mg-11Gd-3Y-0.5Zr(wt.%)alloy over a temperature range of 150℃–450℃under strain rates of 10^(-3) s^(-1)(low strain rate(LSR))and 10 s^(-1)(high strain rate(HSR))to explore the strain rate-temperature coupling effects during hot deformation.The results revealed an anomalous increase in peak stress at 150℃–250℃as the strain rate decreased,attributed to the combined effects of nano-precipitates,dislocation cell structures,and serrated flow induced by dynamic strain aging.At higher temperatures,strain rate influences softening pathways:under HSR at 450℃,the effect of twinning shifts from strengthening to facilitating dynamic recrystallization(DRX),resulting in substantial grain refinement(-4 μm,81%area fraction at a strain of 0.6).In contrast,at LSR,softening is dominated by dynamic recovery at 350℃,with limited DRX(-4 μm grains,10%area fraction at a strain of 0.6)occurs at 400℃.These findings clarify the dual role of twinning and its interaction with rate-temperature conditions,providing valuable insights into optimizing the hot processing of rare-earth magnesium alloys. 展开更多
关键词 Mg-RE alloys Rate-temperature coupling Anomalous strengthening Hot deformation Softening behavior
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High-quality genome of Firmiana hainanensis provides insights into the evolution of Malvaceae subfamilies and the mechanism of their wood density formation
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作者 Zeyu Dong Shangkun Jin +11 位作者 Rui Fan Pengcheng Sun Lei Shao Ting Zhao Haojie Jiang Zhiyuan Zhang Haihong Shang Xueying Guan Yan Hu Tianzhen Zhang Fuyuan Zhu Lei Fang 《Journal of Genetics and Genomics》 2025年第6期812-825,共14页
The Malvaceae family,the most diverse family in the order Malvales,consists of nine subfamilies.Within the Firmiana genus of the Sterculioideae subfamily,most species are considered globally vulnerable,yet their genom... The Malvaceae family,the most diverse family in the order Malvales,consists of nine subfamilies.Within the Firmiana genus of the Sterculioideae subfamily,most species are considered globally vulnerable,yet their genomes remain unexplored.Here,we present a chromosome-level genome assembly for a representative Firmiana species,F.hainanensis,2n=40,totaling 1536 Mb.Phylogenomic analysis shows that F.hainanensis and Durio zibethinus have the closest evolutionary relationship,with an estimated divergence time of approximately 21 millions of years ago(MYA)and distinct polyploidization events in their histories.Evolutionary trajectory analyses indicate that fissions and fusions may play a crucial role in chromosome number variation(2n=14 to 2n=96).Analysis of repetitive elements among Malvaceae reveals that the Tekay subfamily(belonging to the Gypsy group)contributes to variation in genome size(ranging from 324 Mb to 1620 Mb).Additionally,genes associated with P450,peroxidase,and microtubules,and thereby related to cell wall biosynthesis,are significantly contracted in F.hainanensis,potentially leading to its lower wood density relative to Hopea hainanensis.Overall,our study provides insights into the evolution of chromosome number,genome size,and the genetic basis of cell wall biosynthesis in Malvaceae species. 展开更多
关键词 Malvaceae species Genome evolution Ancestral karyotype Transposable elements Cell wall biosynthesis
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Enhanced Boiling Heat Transfer in Water Pools with Perforated Copper Beads and Sodium Dodecyl Sulfate Surfactant
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作者 Pengcheng Cai Teng Li +4 位作者 Jianxin Xu Xiaobo Li Zhiqiang Li Zhiwen Xu Hua Wang 《Fluid Dynamics & Materials Processing》 2025年第2期325-349,共25页
In modern engineering,enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials.This study explores the enhancement of pool... In modern engineering,enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials.This study explores the enhancement of pool boiling heat transfer potentially induced by combining perforated copper particles on a heated surface with a sodium dodecyl sulfate(SDS)surfactant in saturated deionized water.Experiments were conducted at standard atmospheric pressure,with heat flux ranging from 20 to 100 kW/m2.The heating surface,positioned below the layer of freely moving copper beads,allowed the particle layer to shift due to liquid convection and steam nucleation.The study reports on the influence of copper bead diameter(2,3,4,and 5 mm),particle quantity,arrangement,and SDS concentration(20,200,and 500 ppm).It is shown that the combination of 5 mm particles and a 500 ppm SDS concentration can yield a remarkable 139%improvement in heat transfer efficiency.As demonstrated by direct flow visualization,bubble formation occurs primarily in the gaps between the particles and the heated surface,with the presence of SDS reducing bubble size and accelerating bubble detachment. 展开更多
关键词 Pool boiling heat transfer enhancement perforated copper beads SURFACTANT bubble nucleation mechanism flow visualization
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Improved Approach Based on Meander Line Coil Electromagnetic Acoustic Transducers for A0 Wave Enhancement
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作者 LYU Zongmin GUAN Wei +1 位作者 ZHANG Yinghong QIAN Zhenghua 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第6期841-851,共11页
In traditional meander line coil electromagnetic acoustic transducer(MLC-EMAT)structures,the bias magnetic field is usually set to be along the normal direction of plate surface.However,since the particle vibration of... In traditional meander line coil electromagnetic acoustic transducer(MLC-EMAT)structures,the bias magnetic field is usually set to be along the normal direction of plate surface.However,since the particle vibration of the antisymmetric Lamb wave is always dominated by out-of-plane components,using bias magnetic field perpendicular to plate surface is kind of inefficient.In this paper,the performance of both the normal bias magnetic field EMAT(NB-EMAT)and the parallel bias magnetic field EMAT(PB-EMAT)for transmitting and receiving A0 mode Lamb waves are thoroughly studied.The mechanisms of these two structures are elaborated.First,the finite element models of both structures are established.The magnetic fields of these two EMATs are numerically calculated and the results are compared with experiments.Then,the Lorentz force distributions excited by the two EMATs are compared to prove the feasibility of improving the excitation efficiency of MLC-EMAT by selecting the direction of bias magnetic field.Furthermore,the excitation efficiencies of NB-EMAT and PB-EMAT are quantitatively analyzed and compared in simulation software.Results show that the excitation efficiency of PB-EMAT is 108%higher than NB-EMAT.Finally,several groups of comparative experiments are conducted to verify the conclusion obtained through numerical calculation.Experimental results show that by simply replacing the tradition NB-EMAT with PB-EMAT,the excitation efficiency can be greatly increased by more than 50%.If PB-EMATs are used as both the receiver and transmitter,the excitation efficiency can be further increased by 113%. 展开更多
关键词 electromagnetic acoustic transducer meander line coil Lamb wave A0 wave parallel bias magnetic field
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Elucidating oxygen evolution and reduction mechanisms in nitrogen-doped carbon-based photocatalysts
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作者 Yan Wang Jiaqi Zhang +3 位作者 Xiaofeng Wu Sibo Wang Masakazu Anpo Yuanxing Fang 《Chinese Chemical Letters》 2025年第2期196-201,共6页
Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associate... Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associated with important reduction reactions,such as oxygen reduction reaction(ORR),which leads to the production of hydrogen peroxide(H_(2)O_(2)).These transitions are instrumental in the emergence and evolution of life.In this study,transition metals were loaded onto nitrogen-doped carbon(NDC)prepared under the primitive Earth's atmospheric conditions.These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination.The chemical pathways initiated by the pristine and metal-loaded NDC were investigated.This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet. 展开更多
关键词 Nitrogen-doped carbon Chemical vapor deposition PHOTOCATALYSIS Water oxidation reaction Oxygen reduction reaction
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The growth mechanism and corrosion resistance of laser-assisted plasma electrolytic oxidation(PEO)composite coating on AZ31B magnesium alloy
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作者 Guolong Wu Lin Li +4 位作者 Xianghui Chen Lebin Zhu Ye Wang Chen Wen Jianhua Yao 《Journal of Magnesium and Alloys》 2025年第2期760-776,共17页
In this study,laser-assisted plasma electrolytic oxidation(Laser/PEO)coating was prepared on AZ31B magnesium alloy for corrosion protection,due to insufficient corrosion protection caused by the inherent defects,crack... In this study,laser-assisted plasma electrolytic oxidation(Laser/PEO)coating was prepared on AZ31B magnesium alloy for corrosion protection,due to insufficient corrosion protection caused by the inherent defects,cracks and poor quality of PEO coatings.The plasma discharge evolution,morphological characteristics,elemental composition during coating growth were characterized by high-speed camera,SEM,EDX,XRD and XPS,respectively.Meanwhile,Mott Schottky(M-S)curves,potentiodynamic polarization(PDP)curves and electrochemical impedance spectroscopy(EIS)tests characterized the oxygen vacancy defects and corrosion resistance of the coatings.The results demonstrated that laser-assisted irradiation not only induced plasma discharge on the anode surface,but also limited the plasma discharge size in the post-processing stage,which significantly increased the proportion of corrosion-resistant phase Mg_(2)SiO_(4)(the proportion of Mg_(2)SiO_(4)increased from 23.70%to 39.22%),thickness and density in the coating,and obviously reduced the oxygen vacancy defects and microcracks in the coating.As a result,the corrosion resistance of the Laser/PEO coating(9.29(±0.76)×10^(-7)A·cm^(-2))was further enhanced in comparation with the PEO coating(3.06(±0.19)×10^(-6) A·cm^(-2)). 展开更多
关键词 AZ31B magnesium alloy LASER Plasma electrolytic oxidation Coating growth mechanism Corrosion resistance
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Characteristics of pore-throat structures in volatile oil reservoirs and strategies for optimal development
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作者 Ying Tang Zhao Li +3 位作者 Shuai Yin Ruifei Wang Kai Feng Tao Jiang 《Energy Geoscience》 2025年第3期121-132,共12页
The third member of Shahejie Formation(also referred to as Sha 3 Member)in Dongpu Depression,China,a volatile,low-permeability oil reservoir with complex fluid compositions,is subjected to high temperature and high pr... The third member of Shahejie Formation(also referred to as Sha 3 Member)in Dongpu Depression,China,a volatile,low-permeability oil reservoir with complex fluid compositions,is subjected to high temperature and high pressure(HPHT),which poses significant challenges to conventional water injection.To elucidate flow mechanisms and optimize development strategies,this study integrates constant-rate mercury injection(CRMI),nuclear magnetic resonance(NMR),and HPHT three-phase oil/gas/water relative permeability experiments to analyze pore-throat structures,movable fluid characteristics,and relative permeability.The CRMI results indicate that the reservoir exhibits low porosity and low permeability,with dominant throat radius ranging from 0.6 to 5.0μm,and mean pore-throat radius ratio ranging from 40.303 to 278.320,demonstrating significant microscopic heterogeneity.The NMR results reveal that water-alternating-gas(WAG)injection enhances oil recovery by 16.28%(Sample W1)and 13.52%(Sample W2)compared to conventional water injection,primarily due to the gas phase's low viscosity and high mobility,enabling access to micropores unreachable by water phases.The HPHT three-phase relative permeability tests demonstrate positive correlations between saturation and relative permeability,with oil permeability significantly influenced by three-phase saturation and rock wettability.These findings establish a microscopic seepage model for optimizing enhanced oil recovery(EOR)strategies in volatile reservoirs. 展开更多
关键词 Dongpu Depression Volatile reservoir Pore-throat structure Three-phase relative permeability Development strategy
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