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An innovative design driven by contact performances for skiving of spur face gear drive with single cutter
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作者 TANG Zhong-wei ZHOU Yuan-sheng +4 位作者 MO Shuai TANG Jin-yuan MA Chi ZHANG Wu-ji HE Hai-yu 《Journal of Central South University》 2026年第1期175-188,共14页
This study develops a contact performance-driven method for skiving face gear drives using a single cutter,eliminating the traditional need for separate cutters to reduce production costs and time.First,the mathematic... This study develops a contact performance-driven method for skiving face gear drives using a single cutter,eliminating the traditional need for separate cutters to reduce production costs and time.First,the mathematical models of the tooth flanks for the face gear drives are established based on the gear skiving processes.Then,load tooth contact analysis(LTCA)model is established to calculate the contact performance data.Next,a two-stage optimization model is employed to determine the optimal parameters of the cutting edge with improved contact performances.The effectiveness of this method is validated through simulations and rolling tests.Compared with the traditional method,the proposed method can machine both the face gear and its mating pinion with a single cutter.Simulation results show that the proposed method avoids tooth surface edge contact,with the maximum tooth surface contact stress reduced by 31.7%,the contact ratio decreases by 21.5%,and the transmission error increases by 22.3%.Rolling tests verify the consistency of tooth surface contact patterns between simulations and experiments.The proposed method provides a reference for the cutting edge design of skiving cutters for face gear pairs. 展开更多
关键词 face gear drives gear skiving load tooth contact analysis contact performances cutter design
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Functionalized Separators Boosting Electrochemical Performances for Lithium Batteries 被引量:4
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作者 Zixin Fan Xiaoyu Chen +5 位作者 Jingjing Shi Hui Nie Xiaoming Zhang Xingping Zhou Xiaolin Xie Zhigang Xue 《Nano-Micro Letters》 2025年第6期55-92,共38页
The growing demands for energy storage systems,electric vehicles,and portable electronics have significantly pushed forward the need for safe and reliable lithium batteries.It is essential to design functional separat... The growing demands for energy storage systems,electric vehicles,and portable electronics have significantly pushed forward the need for safe and reliable lithium batteries.It is essential to design functional separators with improved mechanical and electrochemical characteristics.This review covers the improved mechanical and electrochemical performances as well as the advancements made in the design of separators utilizing a variety of techniques.In terms of electrolyte wettability and adhesion of the coating materials,we provide an overview of the current status of research on coated separators,in situ modified separators,and grafting modified separators,and elaborate additional performance parameters of interest.The characteristics of inorganics coated separators,organic framework coated separators and inorganic-organic coated separators from different fabrication methods are compared.Future directions regarding new modified materials,manufacturing process,quantitative analysis of adhesion and so on are proposed toward next-generation advanced lithium batteries. 展开更多
关键词 SEPARATORS Polymer electrolytes Lithium batteries Electrochemical performances FUNCTIONALIZATION
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Machine learning approaches for predicting impact sensitivity and detonation performances of energetic materials 被引量:3
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作者 Wei-Hong Liu Qi-Jun Liu +1 位作者 Fu-Sheng Liu Zheng-Tang Liu 《Journal of Energy Chemistry》 2025年第3期161-171,共11页
Excellent detonation performances and low sensitivity are prerequisites for the deployment of energetic materials.Exploring the underlying factors that affect impact sensitivity and detonation performances as well as ... Excellent detonation performances and low sensitivity are prerequisites for the deployment of energetic materials.Exploring the underlying factors that affect impact sensitivity and detonation performances as well as exploring how to obtain materials with desired properties remains a long-term challenge.Machine learning with its ability to solve complex tasks and perform robust data processing can reveal the relationship between performance and descriptive indicators,potentially accelerating the development process of energetic materials.In this background,impact sensitivity,detonation performances,and 28 physicochemical parameters for 222 energetic materials from density functional theory calculations and published literature were sorted out.Four machine learning algorithms were employed to predict various properties of energetic materials,including impact sensitivity,detonation velocity,detonation pressure,and Gurney energy.Analysis of Pearson coefficients and feature importance showed that the heat of explosion,oxygen balance,decomposition products,and HOMO energy levels have a strong correlation with the impact sensitivity of energetic materials.Oxygen balance,decomposition products,and density have a strong correlation with detonation performances.Utilizing impact sensitivity of 2,3,4-trinitrotoluene and the detonation performances of 2,4,6-trinitrobenzene-1,3,5-triamine as the benchmark,the analysis of feature importance rankings and statistical data revealed the optimal range of key features balancing impact sensitivity and detonation performances:oxygen balance values should be between-40%and-30%,density should range from 1.66 to 1.72 g/cm^(3),HOMO energy levels should be between-6.34 and-6.31 eV,and lipophilicity should be between-1.0 and 0.1,4.49 and 5.59.These findings not only offer important insights into the impact sensitivity and detonation performances of energetic materials,but also provide a theoretical guidance paradigm for the design and development of new energetic materials with optimal detonation performances and reduced sensitivity. 展开更多
关键词 Energetic materials Machine learning Impact sensitivity Detonation performances Feature descriptors Balancing strategy
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Properties and performances of high-entropy materials in batteries 被引量:1
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作者 Jiasheng Wang Jianzhong Jiang +1 位作者 Peter KLiaw Yong Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2786-2805,共20页
High-entropy materials(HEMs),an innovative class of materials with complex stoichiometry,have recently garnered consider-able attention in energy storage applications.While their multi-element compositions(five or mor... High-entropy materials(HEMs),an innovative class of materials with complex stoichiometry,have recently garnered consider-able attention in energy storage applications.While their multi-element compositions(five or more principal elements in nearly equiatom-ic proportions)confer unique advantages such as high configurational entropy,lattice distortion,and synergistic cocktail effects,the fun-damental understanding of structure-property relationships in battery systems remains fragmented across existing studies.This review ad-dresses critical research gaps by proposing a multidimensional design paradigm that systematically integrates synergistic mechanisms spanning cathodes,anodes,electrolytes,and electrocatalysts.We provide an in-depth analysis of HEMs’thermodynamic/kinetic stabiliza-tion principles and structure-regulated electrochemical properties,integrating and establishing quantitative correlations between entropy-driven phase stability and charge transport dynamics.By summarizing the performance benchmarking results of lithium/sodium/potassi-um-ion battery components,we reveal how entropy-mediated structural tailoring enhances cycle stability and ionic conductivity.Notably,we pioneer the systematic association of high-entropy effects to electrochemical interfaces,demonstrating their unique potential in stabil-izing solid-electrolyte interphases and suppressing transition metal dissolution.Emerging opportunities in machine learning-driven com-position screening and sustainable manufacturing are discussed alongside critical challenges,including performance variability metrics and cost-benefit analysis for industrial implementation.This work provides both fundamental insights and practical guidelines for advan-cing HEMs toward next-generation battery technologies. 展开更多
关键词 high-entropy materials energy storage battery performance electrochemical properties battery systems
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Workability and Mechanical Performances of Cement Paste with Nano-TiO_(2)
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作者 WANG Zigeng SHEN Yonghao +1 位作者 LI Yue DU Huan 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1286-1296,共11页
This article investigated the factors and mechanisms that affected the workability and mechanical properties of cement paste incorporating nano-TiO_(2).The findings indicated that,for nano-TiO_(2)aqueous solution conc... This article investigated the factors and mechanisms that affected the workability and mechanical properties of cement paste incorporating nano-TiO_(2).The findings indicated that,for nano-TiO_(2)aqueous solution concentrations of 3%,6%,9%,and 12%,the optimal dispersion effect was achieved with an ultrasonic dispersion time of 20 minutes.Specifically,at a 6%nano-TiO_(2)content,both the workability and mechanical performance of the cement paste were enhanced.Furthermore,while nano-TiO_(2)did not alter the types of hydration products present in the cement paste,it did increase the amount of C-S-H gels.This enhancement was attributed to a higher number of nucleation sites for hydration products,which promoted hydration and reduced the porosity of the cement paste. 展开更多
关键词 cement paste nano-TiO_(2) workability performance mechanical performance microscopic analysis
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Synthesis of Nano-CuF_(2) with Superior Electrochemical Performances via a Mixed Solvent Coprecipitation Method
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作者 DU Suni YU Zhiyong +5 位作者 JI Erte XU Hanchen ZHAO Yichun LIU Hanxing LAI Caiting YUAN Zhongzhi 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1206-1212,共7页
Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced eff... Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced effect on both the particle size and the extent of agglomeration.With the increase in methanol content,the particle size and agglomeration of CuF_(2) decreased first and then increased.When the volume ratio of methanol to deionized water was 1:1,the CuF_(2) particles exhibited the smallest size and the lowest degree of agglomeration.CuF_(2) synthesized with 50%methanol exhibited superior electrochemical performances with a voltage plateau above 3 V and a 1st discharge capacity of 525.8 mAh·g^(-1) at 0.01 C due to the synergistic influence of the particle size and dispersion.The analysis results using electrochemical impedance spectroscopy(EIS)and constant current intermittent titration technique(GITT)affirmed the addition of methanol was beneficial for promoting Li+diffusion and accelerating electrochemical reaction kinetics of CuF_(2). 展开更多
关键词 CuF_(2) lithium-ion battery mixed solvent co-precipitation method electrochemical performances
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Full-scale performances of the slab track subgrade filled with basalt fiber-reinforced foamed concrete
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作者 Zhichao Huang Qian Su +3 位作者 Wenhui Zhao Zongyu Zhang Junjie Huang Sakdirat Kaewunruen 《Railway Engineering Science》 2025年第2期238-258,共21页
Foamed concrete has been used to address the issue of differential settlement in high-speed railway subgrades in China.However,to enhance crack resistance,reinforcement is still necessary,and further research is requi... Foamed concrete has been used to address the issue of differential settlement in high-speed railway subgrades in China.However,to enhance crack resistance,reinforcement is still necessary,and further research is required to better understand the performance of foamed concrete in subgrade applications.To this end,a series of tests—including uniaxial compres-sive and dynamic triaxial tests—were conducted to comprehensively examine the effects of basalt fiber reinforcement on the mechanical properties of foamed concrete with densities of 700 and 1000 kg/m3.Additionally,a full-scale model of the foamed concrete subgrade was established,and simulated loading was applied.The diffusion patterns of dynamic stress and dynamic acceleration within the subgrade were explored,leading to the development of experimental formulas to calculate the attenuation coefficients of these two parameters along the depth and width of the subgrade.Furthermore,the dynamic displacement and cumulative settlement were analyzed to evaluate the stability of the subgrade.These findings provide valuable insights for the design and construction of foamed concrete subgrades in high-speed rail systems.The outcomes are currently under consideration for inclusion in the code of practice for high-speed rail restoration. 展开更多
关键词 High-speed railway Slab track subgrade Basalt fiber-reinforced foamed concrete Model testing Dynamic performances
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Evaluation of the Agronomic Performances of Eight Varieties of Orange-Fleshed Sweet Potato in Central Côte d’Ivoire
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作者 Konan Evrard Brice Dibi Niambet Jean-Michel Koffi +5 位作者 Adou Emmanuel Ehounou Brice Sidoine Essis Kouassi Thiègba Kouamé Kinampinan Adelphe Hala Adjo Christiane Koffi Guy Fernand Yao 《American Journal of Plant Sciences》 2025年第2期301-315,共15页
Sweet potato is one of the most important crops in Côte d’Ivoire. However, some constraints related to climate change limit its production. This study evaluated the agronomic and technological performances of ei... Sweet potato is one of the most important crops in Côte d’Ivoire. However, some constraints related to climate change limit its production. This study evaluated the agronomic and technological performances of eight varieties of orange-fleshed of sweet potato (Ipomoea batatas (L.) to identify the most promising ones. The results show three groups of varieties with different agronomic performances. Group 1 composed of Irene and Vita is characterized by low production of small and large tuberous roots, low number of productive plants and low yield. Group 2 consisting mainly of Kabode is characterized by high production and weight of large tuberous roots as well as high yield. Group 3, composed of Tacha-2 Ininda, Ejumula Gloria, TIB-440060, CIP-199062-1, Bela bela is characterized by high production of small and large tuberous roots, high number of productive plants and average yield. The TIB-440060 variety has a recovery rate of 100%. The Irene, Kabode, Vita, Kabode varieties were resistant to viral and fungal diseases. In terms of technological quality, the TIB-440060 and CIP-199062-1 varieties have the best organoleptic qualities. Given the agronomic performances of the Kabode, TIB-440060 and CIP-199062-1 varieties, could be selected as the elites varieties and distributed to producers. 展开更多
关键词 Sweet Potato Agronomic and Technological performances Climate Change Côte d’Ivoire
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Comparative Study on Hydrodynamic Performances of Fully Activated and Semi-Activated Oscillating Hydrofoils for Energy Harvesting
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作者 QU Hengliang LI Xueyan +1 位作者 SHI Hongyuan DONG Xiaochen 《Journal of Ocean University of China》 2025年第1期31-39,共9页
The oscillating hydrofoil represents a promising technology for harvesting energy from tidal currents.While previous research has primarily focused on oscillating hydrofoils utilizing a fully activated control strateg... The oscillating hydrofoil represents a promising technology for harvesting energy from tidal currents.While previous research has primarily focused on oscillating hydrofoils utilizing a fully activated control strategy,the industry predominantly employs a semi-activated control strategy in existing tidal current energy converters.It is essential to identify the differences in predicted energy-harvesting performance between these two controlling strategies through experimental modeling or numerical studies.Furthermore,the suitability of the fully activated control strategy in predicting the energy-harvesting capabilities of oscillating hydrofoils is evaluated.The 2D numerical models of hydrofoil based on fully activated and semi-activated control strategies have been developed and validated.The amplitudes of heaving and pitching movements for the fully activated hydrofoil are determined to match those of the semi-activated hydrofoil.The results show that the main difference between the two control strategies lies in the phase shift occurring between the pitching and heaving motions.This phase shift affects the lift force and its coordination with the heaving velocity,which in turn affects the power output.Notably,the maximum relative efficiency difference obtained between the fully activated and semi-activated control strategies can reach 191%. 展开更多
关键词 oscillating hydrofoil controlling strategy comparative study energy-harvesting performance
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Surface segregation-intensified physical vapor deposition of TiO_(2) on polyether sulfone membranes for enhanced antifouling performances
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作者 Hong-Jian Wang Hai-Xia Wang +6 位作者 Yang-Yang Song Ke-Wei Qiu Yu-Zhu Liu Guo-Cheng Yao Wen-Liang Li Ya-Nan Liu Fu-Sheng Pan 《Rare Metals》 2025年第5期3362-3375,共14页
Coating techniques are efficient routes to modify surface property of composite membranes for enhanced membrane separations.However,it remains challenge to deposit continuous inorganic layers on hollow fiber substrate... Coating techniques are efficient routes to modify surface property of composite membranes for enhanced membrane separations.However,it remains challenge to deposit continuous inorganic layers on hollow fiber substrates.This study combines surface segregation with physical vapor deposition(PVD)to construct intensified TiO_(2)layers on polyether sulfone(PES)hollow fiber substrates.During membrane fabrication,polyethylene-polypropylene glycol(F127)is used as surface segregation agent in casting solution,which enables PES hollow fibers with abundant hydroxy groups,thus improving the compatibility between PES and vaporized TiO_(2).The obtained PES/F127@TiO_(2)membranes exhibit tight TiO_(2)layers with tunable thickness,high mechanical strength,narrowed pore size and enhanced hydrophilicity.Moreover,the optimized PES/F127@TiO_(2)membranes show competitive antifouling performances in water treatment,with a water permeability up to 97 L·m^(-2)·h^(-1)·bar^(-1)and bovine serum albumin(BSA)rejection of~99%.This work is expected to provide a material design idea to deposit functional layers on polymers for fortified performances. 展开更多
关键词 Surface segregation Membrane separation Antifouling performance Physical vapor deposition TiO_(2)coating
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Thermo-Hydraulic Performances of Microchannel Heat Sinks with Different Types of Perforated Rectangular Blocks
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作者 Heng Zhao Honghua Ma +4 位作者 Hui Liu Xiang Yan Huaqing Yu Yongjun Xiao Xiao Xiao 《Fluid Dynamics & Materials Processing》 2025年第1期87-105,共19页
The behavior of single-phase flow and conjugate heat transfer in micro-channel heat sinks(MCHS)subjected to auniform heat flux is investigated by means of numerical simulations.Various geometrical configurations areex... The behavior of single-phase flow and conjugate heat transfer in micro-channel heat sinks(MCHS)subjected to auniform heat flux is investigated by means of numerical simulations.Various geometrical configurations areexamined,particularly,the combinations of rectangular solid and perforated blocks,used to create a disturbancein the flow.The analysis focuses on several key aspects and related metrics,including the temperature distribution,the mean Fanning friction factor,the pressure drop,the Nusselt number,and the overall heat transfer coefficientacross a range of Reynolds numbers(80–870).It is shown that the introduction of such blocks significantlyenhances the heat transfer performances of the MCHS compared to the straight-through flow channel.Specifically,a case is found where the Nusselt number increases by 2.3 times relative to the reference case.The integrationof perforated blocks facilitates the generation of vorticity within the channel,promoting the mixing of coldand hot fluids.Notably,MCHS incorporating perforated rectangular blocks exhibit more pronounced heat transferbenefits at Reynolds numbers smaller than 400. 展开更多
关键词 Micro-channel heat sink(MCHS) perforated rectangular blocks thermal performance convection heat transfer
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地方产业链政策创新能实现企业“经济—环境”双赢吗?——基于产业链“链长制”的准自然实验
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作者 曾辉祥 刘辰雲 +2 位作者 周琼 金友良 龚方圆 《财经研究》 北大核心 2026年第1期36-48,共13页
作为地方政府提升产业链现代化水平的政策创新,产业链“链长制”是推动企业实现“经济—环境”双赢的有效抓手。文章以2013—2020年中国沪深A股上市公司为样本,探讨了产业链“链长制”对企业绩效的影响及作用路径。研究发现,产业链“链... 作为地方政府提升产业链现代化水平的政策创新,产业链“链长制”是推动企业实现“经济—环境”双赢的有效抓手。文章以2013—2020年中国沪深A股上市公司为样本,探讨了产业链“链长制”对企业绩效的影响及作用路径。研究发现,产业链“链长制”可提升企业经济绩效与环境绩效,实现“经济—环境”双赢;尤其是在融资约束程度较低、创新能力较强、非国有企业以及高端制造、生物医药等行业的企业中效果更加显著。进一步分析表明,发挥链主企业的支点效应与提升企业产业链话语权是“链长制”实现“经济—环境”双赢的共有机制;协调政府与市场在产业链运行中的互动作用是“链长制”提升企业经济绩效的特有渠道,促进链上企业协同减排则是“链长制”助力环境绩效跃迁的独特路径。文章的研究结论对优化我国产业政策体系和推进企业高质量发展具有重要的参考价值。 展开更多
关键词 产业链政策 产业链“链长制” 经济绩效 环境绩效
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Studies on Transferrin and Posttremsferr Polymorphism and Their Relationship with Performances in Red Steppe 被引量:6
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作者 张永宏 潘英树 +5 位作者 高妍 马倩 刘同欣 秦莹 赵志辉 张嘉保 《Agricultural Science & Technology》 CAS 2008年第5期109-112,共4页
[Objective] The aim of this study was to investigate the correlation between blood protein polymorphism of red steppe and its performance.[Method]Two blood protein polymorphic loci were detected in transferring(Tf)and... [Objective] The aim of this study was to investigate the correlation between blood protein polymorphism of red steppe and its performance.[Method]Two blood protein polymorphic loci were detected in transferring(Tf)and posttremsferr(Ptf)from thirteen red steppes and eighteen hybrid of limousin and red steppe by polyacrylamide gel electrophoresis.[Result]Tf and Ptf were controlled by three and two alleles respectively.[Conclusion]The variance analysis of blood protein polymorphic loci and its performance indicates that two protein loci have a positive or negative correlation with some traits of red steppe and the improved limousin cattle population. 展开更多
关键词 RED STEPPE Transferring Posttremsferr POLYMORPHISM performance
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合同无效与履约保证金返还——探索超越“全有或全无”的第三条道路
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作者 韩世远 《云南社会科学》 北大核心 2026年第1期107-117,共11页
因合同无效,基于该合同给付的履约保证金依法可以主张返还,相应的返还请求权通常是给付不当得利返还请求权。履约保证金作为给付不当得利请求返还,通常作为“返还财产”即为已足,无须“折价补偿”(价额偿还)。“得利”可以表现为对金钱... 因合同无效,基于该合同给付的履约保证金依法可以主张返还,相应的返还请求权通常是给付不当得利返还请求权。履约保证金作为给付不当得利请求返还,通常作为“返还财产”即为已足,无须“折价补偿”(价额偿还)。“得利”可以表现为对金钱的受领,“返还财产”则须依不当得利法则确定其返还的方法与范围,可能但却并非必然是当初所受领的金钱。在接力给付形成给付链条且两份合同均属无效(双重瑕疵)场合,善意的接力给付人的现存利益可能表现为其对第三人的不当得利请求权,该请求权作为接力给付人所受领履约保证金的代偿物,构成相应的返还客体。这种“双重不当得利请求权”能够精准对应当事人事先对于履约保证金返还风险的分配,因其给予每个人其所应得,故更为公正。 展开更多
关键词 不当得利 履约保证金 返还财产 代偿物 给付链条
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补饲富硒复合营养舔砖对天祝白牦牛生产性能的影响
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作者 郭全奎 王璐菊 +3 位作者 唐德富 王晨阳 苏鹏伟 马林 《饲料工业》 北大核心 2026年第1期81-86,共6页
试验旨在研究富硒复合营养舔砖对天祝白牦牛生长性能、屠宰性能及经济效益的影响。选择30头体型一致、体重为(150.38±15.38) kg的天祝白牦牛公牛,随机分为3组,每组10头。对照组不补饲舔砖,试验Ⅰ组舔饲普通复合营养舔砖(硒含量3 mg... 试验旨在研究富硒复合营养舔砖对天祝白牦牛生长性能、屠宰性能及经济效益的影响。选择30头体型一致、体重为(150.38±15.38) kg的天祝白牦牛公牛,随机分为3组,每组10头。对照组不补饲舔砖,试验Ⅰ组舔饲普通复合营养舔砖(硒含量3 mg/kg),试验Ⅱ组舔饲富硒复合营养舔砖(硒含量20 mg/kg),试验所用基础饲粮均一致。试验分为2个阶段,预试期15 d,正试期105 d。结果显示:两个试验组显著提升了平均日增重和干物质采食量,并降低了料重比(P<0.05);试验Ⅱ组屠宰率、胴体重、净肉重、骨重、肉骨比、剪切力显著高于对照组(P<0.05);试验Ⅱ组超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性显著高于对照组(P<0.05),丙二醛(MDA)含量显著降低(P<0.05);试验Ⅱ组纯收入达784.39元/头,显著高于试验Ⅰ组(551.45元/头)和对照组(255.23元/头)。综上所述,补饲20 mg/kg富硒复合营养舔砖会显著提高天祝白牦牛的生长性能、屠宰性能及经济效益,且对其血清抗氧化指标有显著影响。 展开更多
关键词 富硒复合营养舔砖 天祝白牦牛 生长性能 屠宰性能 抗氧化指标
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基于观测状态修正的微电网储能双向DC-DC变换器自抗扰稳压策略
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作者 周雪松 景亚楠 +3 位作者 马幼捷 王鑫 陶珑 问虎龙 《电力自动化设备》 北大核心 2026年第1期185-193,共9页
在直流微电网中,高比例光伏设备的出力波动需要储能单元进行补偿和调节,但在复杂工况下,储能端口双向DC-DC变换器的稳压性能往往不能得到有效保障。为此,以直流微电网中的储能双向DC-DC变换器为研究对象,提出一种考虑观测偏差高阶修正... 在直流微电网中,高比例光伏设备的出力波动需要储能单元进行补偿和调节,但在复杂工况下,储能端口双向DC-DC变换器的稳压性能往往不能得到有效保障。为此,以直流微电网中的储能双向DC-DC变换器为研究对象,提出一种考虑观测偏差高阶修正的自抗扰稳压策略。将传统自抗扰控制中被忽略的偏差项定义为扰动观测高阶分量,并将其补偿到观测器结构中得到精确的修正变量,实现自抗扰观测偏差的精准和快速收敛;从时域、频域维度分析该策略能够有效改善观测性、抗扰性、鲁棒性的原因,并利用李雅普诺夫理论证明所提控制策略的稳定性。仿真结果表明,所提策略控制下的储能双向DC-DC变换器在多种复杂场景中均表现出较好的抗扰性和鲁棒性。 展开更多
关键词 微电网 自抗扰控制 变换器 状态修正 抗扰性能 鲁棒性能
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骆驼布鲁氏菌病血清学诊断方法效能分析研究
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作者 马晓菁 叶锋 +6 位作者 努尔拜合提·努尔旦 刘丽娅 夏江涛 舍卫俊 王校敏 章健 易新萍 《中国人兽共患病学报》 北大核心 2026年第1期41-45,共5页
目的分析布病虎红平板凝集试验(RBT)、间接酶联免疫吸附试验(iELISA)、竞争酶联免疫吸附试验(cELISA)和高敏荧光层析法(LFICA)4种血清学检测方法对骆驼布病的诊断效能,为骆驼布病防控提供技术支撑。方法分别采用布病RBT、iELISA、cELISA... 目的分析布病虎红平板凝集试验(RBT)、间接酶联免疫吸附试验(iELISA)、竞争酶联免疫吸附试验(cELISA)和高敏荧光层析法(LFICA)4种血清学检测方法对骆驼布病的诊断效能,为骆驼布病防控提供技术支撑。方法分别采用布病RBT、iELISA、cELISA和LFICA方法对40份骆驼布病标准血清和151份不同地区采集骆驼血清进行布病检测,结果经SPSS 27.0软件分析Kappa值并绘制ROC曲线,从灵敏度、特异性指标比较不同方法检测结果一致性。结果4种检测方法中RBT方法与iELISA、cELISA和LFICA方法一致性较差(Kappa值<0.38);iELISA、cELISA和LFICA方法间检测一致性较高(Kappa值>0.85)。ROC曲线效能评价表明iELISA、cELISA、LFICA方法均适合骆驼布病血清学诊断,其中LFICA方法诊断准确率最高(AUC值=0.98),iELISA、cELISA方法诊断准确率的AUC值分别为0.95和0.90。结论LFICA方法以其灵敏性高、特异性强、简单快速等优点更适用于骆驼调运、流行病学调查、乳样现场生物安全监管的布病检测。 展开更多
关键词 骆驼 布鲁氏菌病 血清学方法 诊断效能
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寒区高黏沥青低温流变及混合料路用性能研究
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作者 马峰 伍赛林 +4 位作者 姜欣野 傅珍 郝宏剑 祝崇鑫 张璟 《功能材料》 北大核心 2026年第2期1-9,共9页
为进一步提升高黏沥青在寒区路面的低温性能及其混合料的路用性能,研究向基质沥青中分别掺入10%、12%、14%和16%的HVA高黏添加剂,制备高黏改性沥青。通过三大指标及布氏黏度试验评估其基本性能,并采用低温蠕变与应力松弛试验研究其低温... 为进一步提升高黏沥青在寒区路面的低温性能及其混合料的路用性能,研究向基质沥青中分别掺入10%、12%、14%和16%的HVA高黏添加剂,制备高黏改性沥青。通过三大指标及布氏黏度试验评估其基本性能,并采用低温蠕变与应力松弛试验研究其低温流变特性。同时结合车辙、小梁弯曲及冻融劈裂试验,对多孔沥青混合料的路用性能进行系统评价。结果表明,HVA的加入可显著提升沥青高温抗剪切能力。随着HVA掺量的增加,沥青蠕变劲度增大,蠕变速率降低,低温抗裂性能得到强化。同时HVA能够降低沥青剪切应力,增强其低温应力松弛能力,但过高掺量会对沥青低温性能不利,HVA最佳掺量为14%。以HVA高黏改性沥青制备的OGFC-13混合料在高温稳定性与水稳定性方面表现优异,且其弯拉强度与弯曲破坏应变均高于SBS改性沥青混合料,显示出更佳的低温抗裂性能。 展开更多
关键词 道路工程 高黏改性沥青 增黏剂 低温性能 路用性能
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Effects of stoichiometric ratio La/Mg on structures and electrochemical performances of as-cast and annealed La-Mg-Ni-based A_2B_7-type electrode alloys 被引量:3
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作者 张羊换 杨泰 +3 位作者 翟亭亭 袁泽明 张国芳 郭世海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1968-1977,共10页
In order to investigate the influences of the stoichiometric ratio of La/Mg (increasing La and decreasing Mg on the same mole ratio) on the structure and electrochemical performances of the La-Mg-Ni-based A2B7-type ... In order to investigate the influences of the stoichiometric ratio of La/Mg (increasing La and decreasing Mg on the same mole ratio) on the structure and electrochemical performances of the La-Mg-Ni-based A2B7-type electrode alloy, the as-cast and the annealed ternary Lao.8+xMgo.2_xNi3.5 (x=0-0.05) electrode alloys were prepared. The characterization of electrode alloys by X-ray diffraction (XRD) and scanning electron microscopy (SEM) shows that all the as-cast and the annealed alloys hold two major phases of (La,Mg)2Ni7 and LaNi5 as well as a residual phase of LaNi3. Moreover, the increase of La/Mg ratio brings on a decline of (La,Mg)2Ni7 phase and a rise of LaNi5 and LaNi3 phases. The variation of La/Mg ratio gives rise to an evident change of the electrochemical performances of the alloys. The discharge capacities of the as-cast and the annealed alloys evidently decrease with growing the La/Mg ratio, while the cycle stabilities of the alloys visibly augment under the same condition. Furthermore, the high rate discharge ability (HRD), the electrochemical impedance spectrum (EIS), the Tafel polarization curves, and the potential step measurements all indicate that the electrochemical kinetic properties of the alloy electrodes increase with the La/Mg ratio rising. 展开更多
关键词 hydrogen storage alloy annealing treatment structure electrochemical performance KINETICS
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基于混合工质的太阳能驱动有机朗肯循环系统性能分析与多目标优化
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作者 柴俊霖 马丕胤 +2 位作者 杨富斌 张红光 杨照 《化工进展》 北大核心 2026年第1期176-186,共11页
太阳能驱动有机朗肯循环系统中有机工质的选择是影响太阳能热电转换效率与效益的重要因素。为此,研究槽式太阳能集热器热源特性,进而构建槽式太阳能集热场驱动有机朗肯循环系统的热经济性模型。本文选择混合工质R245fa/R1233zd和R245fa/... 太阳能驱动有机朗肯循环系统中有机工质的选择是影响太阳能热电转换效率与效益的重要因素。为此,研究槽式太阳能集热器热源特性,进而构建槽式太阳能集热场驱动有机朗肯循环系统的热经济性模型。本文选择混合工质R245fa/R1233zd和R245fa/R245ca,从热力学和经济性的角度对比分析了混合工质的系统性能。选择蒸发压力、过热度、冷凝温度和R245fa质量分数4个运行参数,研究最大化系统净输出功、最大化系统㶲效率和最小化系统单位能量产出成本的多目标优化问题,使用熵权-TOPSIS决策方法获得帕累托前沿最优解并进行对比分析。结果表明,槽式太阳能集热器导热油温度在453.15K附近时,其综合集热性能最佳。在运行参数较大变化范围内,R245fa的系统净输出功和系统单位能量产出成本较优;R1233zd的系统㶲效率较高;其他不同质量分数的混合工质表现出中等的系统性能。通过优化与决策对比分析,R245fa表现出更高的系统净输出功和更低的系统单位能量产出成本,分别为132.95kW、0.0996USD/kWh;0.9R245fa/0.1R1233zd表现出更高的系统㶲效率,为49.82%。 展开更多
关键词 槽式太阳能集热器 有机朗肯循环 混合工质 热力学性能 经济性 多目标优化
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