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Review:J-integral resistance curve testing and evaluation

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2009年第11期10卷 1541-1560页

作者： xian-kui zhu Battelle Memorial Institute Columbus Ohio 43221 USA

In this paper a critical review is presented of the history.and current state of the art of J-integral resistance curve testing and experimental evaluation methods in conjunction with a discussion of the development of the plane strain fracture toughness test standard ASTM E1820 developed by.American Society.for Testing and Materials (ASTM). Early.research efforts on this topic are reviewed first. These include the J-integral concept, experimental estimates of the J-integral for stationary.cracks, load line displacement (LLD) and crack mouth opening displacement (CMOD) based η factor equations, different formulations of J-integral incremental equations for growing cracks, crack growth corrected J-R curve determination, and experimental test methods. Recent developments in J-R curve testing and evaluation are then described, with emphasis on accurate J-integral incremental equations, a normalization method, a modified basic method, a CMOD direct method with use of incremental equations, relationships of plastic geometry.factors, constraint-dependent J-R curve testing and correction approaches. An overview of the present fracture toughness test standard ASTM E1820-08a is then presented. The review shows that after more than 40 y.ars of investigation and development, the J-integral resistance curve test methods in ASTM E1820 have become simpler, more cost-effective and more accurate.

关键词： J-integral J-R curve Fracture toughness Fracture testing Crack growth

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明代嘉鱼李憭与四邑公堤修筑始末考

湖北科技学院学报 2025年第1期45卷 10-18页

作者：朱志先张霞湖北科技学院人文与传媒学院湖北咸宁437100

从宋代开始,为解决长江水对江夏、嘉鱼、咸宁、蒲圻四地沿江造成的水患,四地主政者不断修筑江堤,各地利害关系不一,所修江堤效果不太理想。明代万历年间,在嘉鱼李憭的呼吁协调下,历时数年,加固老堤,修筑新堤,长达上百里,被誉为四邑公堤... 详细信息

从宋代开始,为解决长江水对江夏、嘉鱼、咸宁、蒲圻四地沿江造成的水患,四地主政者不断修筑江堤,各地利害关系不一,所修江堤效果不太理想。明代万历年间,在嘉鱼李憭的呼吁协调下,历时数年,加固老堤,修筑新堤,长达上百里,被誉为四邑公堤,有效抵制了江水泛滥所造成的危害。其间,李憭在四邑公堤的修筑筹备方面积极倡导和协调,在修筑制度方面采取因地制宜灵活变通的措施,在修筑经费方面据实情合理估算费用,保证四邑公堤顺利完工。

关键词：明代嘉鱼李憭四邑公堤水利

A Model for Predicting Dy.amic Cutting Forces in Sand Mould Milling with Orthogonal Cutting

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 95-105页

作者： Zhong-De Shan Fu-xian zhu State Key.Laboratory.of Advanced Forming Technology.and Equipment China Academy of Machinery Science TechnologyBeijing 100083China Jiangsu University.of Technology Changzhou 213001China

Cutting force is one of the research hotspots in direct sand mould milling because the cutting force directly.a ects the machining quality.and tool wear. Unlike metals, sand mould is a heterogeneous discrete deposition material. There is still a lack of theoretical research on the cutting force. In order to realize the prediction and control of the cut?ting force in the sand mould milling process, an analy.ical model of cutting force is proposed based on the unequal division shear zone model of orthogonal cutting. The deformation velocity.relations of the chip within the orthogonal cutting shear zone are analy.ed first. According to the flow behavior of granular, the unequal division shear zone model of sand mould is presented, in which the governing equations of shear strain rate, strain and velocity.are estab?lished. The constitutive relationship of quasi?solid–liquid transition is introduced to build the 2D constitutive equation and deduce the cutting stress in the mould shear zone. According to the cutting geometric relations of up milling with straight cutting edge and the transformation relationship between cutting stress and cutting force, the dy.amic cutting forces are predicted for di erent milling conditions. Compared with the experimental results, the predicted results show good agreement, indicating that the predictive model of cutting force in milling sand mould is validated. Therefore, the proposed model can provide the theoretical guidance for cutting force control in high e ciency.mill?ing sand mould.

关键词： Green manufacture Cutting force Sand mould milling Orthogonal cutting Quasi?solid–liquid transition

Etching oxide overlay.rs of NiFe phosphide to facilitate surface reconstruction for oxy.en evolution reaction

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Green Energy.& Environment 2022年第3期7卷 365-371页

作者： Tehua Wang xian-zhu Fu Shuangy.n Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen518055China College of Phy.ics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China State Key.Laboratory.of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China

Transition-metal phosphides have been of concern as efficient electrocataly.ts for oxy.en evolution reaction(OER)due to its high conductivity.and earth-abundance ***,oxide overlay.rs formed on their surface by.spontaneously.atmospheric oxidation are usually.neglected,thus confusing the establishment of structure–performance ***,we successfully.etched the oxide overlay.rs of NiFe phosphide(NiFeP)by.a dielectric barrier discharge(DBD)plasma technique,aiming to reveal the influence of the oxide overlay.rs on its electrocataly.ic performance for *** is found that etching the oxide overlay.rs can accelerate the surface reconstruction process of NiFeP and facilitate the formation of metal hy.roxides,which are key.intermediate phases for ***,the etched NiFeP-DBD material shows remarkably.enhanced OER activity.with an overpotential of 265 mV at a current density.of 10 mA cm^(-2).The finding of this work probably.brings a significant impact to understand the structure–performance relationship of metal phosphide in electrooxidation reaction.

关键词： surface oxide evolution

Progress on Regulation of NLRP3 Inflammasome by.Chinese Medicine in Treatment of Ulcerative Colitis

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Chinese Journal of Integrative Medicine 2023年第8期29卷 750-760页

作者： SUN Hao-xian zhu y.ng Department of Gastroenterology the First Affiliated Hospital of Hunan University of Chinese MedicineChangsha(410007)China Hunan University.of Chinese Medicine Changsha(410208)China

Ulcerative colitis(UC)is a chronic,non-specific intestinal disease that not only.affects the quality.of life of patients and their families but also increases the risk of colorectal *** nucleotide-binding oligomerization domain-like receptor family.py.in domain-containing protein 3(NLRP3)inflammasome is an important component of inflammatory.response sy.tem,and its activation induces an inflammatory.cascade response that is involved in the development and progression of UC by.releasing inflammatory.cy.okines,damaging intestinal epithelial cells,and disrupting the intestinal mucosal *** medicine(CM)play. a vital role in the prevention and treatment of UC and is able to regulate NLRP3 *** experimental studies on the regulation of NLRP3 inflammasome mediated by.CM have been carried out,demonstrating that CM formulae with main effects of clearing heat,detoxify.ng toxicity.dry.ng dampness,and activating blood *** and pheny.propanoids can effectively.regulate NLRP3 *** active components of CM can interfere with the process of NLRP3 inflammasome assembly.and activation,leading to a reduction in inflammation and UC ***,the reports are relatively.scattered and lack sy.tematic *** paper reviews the latest findings regarding the NLRP3 inflammasome activation-related pathway. associated with UC and the potential of CM in treating UC through modulation of NLRP3 *** purpose of this review is to explore the possible pathological mechanisms of UC and suggest new directions for development of therapeutic tools.

关键词： NLRP3 inflammasome ulcerative colitis Chinese medicine mechanism of action review

Breeding cotton with superior fiber quality.identification and utilization of multiple elite loci and exotic genetic resources

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Science China(Life Sciences) 2021年第7期64卷 1197-1198页

作者： Gai Huang y.-xian zhu State Key.Laboratory.of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Institute for Advanced Studies Wuhan UniversityWuhan 430072China

In the last decade,cotton genomics had great progress in genome assembling(Li et al.,2015;Huang et al.,2020)and agriculturally.important locus identification(Du et al.,2018;Ma et al.,2018;Li et al.,2021).Upland cotton(Gossy.ium hirsutum)is one of the most important cash crops cultivated *** fiber quality.of cotton directly.determines its economic value,and therefore enhancing fiber quality.is alway. the primary.task in cotton breeding practices(Xia et al.,2019;Huang et al.,2021).

关键词： fiber elite cotton

Nonparametric M-estimation for Functional Stationary.Ergodic Data

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 491-512页

作者： xian-zhu XIONG Zheng-y.n LIN College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China Department of Mathematics Zhejiang UniversityHangzhou 310027China

This paper considers a nonparametric M-estimator of a regression function for functional stationary.ergodic *** precisely.in the ergodic data setting,we consider the regression of a real random variable y.over an explanatory.random variable X taking values in some semi-metric abstract *** some mild conditions,the weak consistency.and the asy.ptotic normality.of the M-estimator are ***,a simulated example is provided to examine the finite sample performance of the M-estimator.

关键词： nonparametric M-estimator functional stationary ergodic data weak consistency asy.ptotic normality

Evaluation of transmission risk of respiratory.particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： Liangy. zhu xian Li Bujin Feng Fan Liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory.infection because the elevator cabin is crowded and has poor *** exhaled particles may.be inhaled by.the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively.reduce the transmission risk of respiratory.particles remains *** this study.the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by.proven computational fluid dy.amics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent lay.ut and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly.reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy.should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dy.amics(CFD)

Neurons-sy.tem-like structured SnS_(2)/CNTs composite for high-performance sodium-ion battery.anode

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Rare Metals 2021年第6期40卷 1383-1390页

作者： Ling zhu Xue-xian y.ng y.n-Hong xiang Peng Kong xian-Wen Wu School of Phy.ics and Electromechanical Engineering Jishou UniversityJishou 416000China School of Chemistry.and Chemical Engineering Jishou UniversityJishou 416000China

Sodium-ion batteries(SIBs)have attracted significant attention with respect to renewable energy.power generation sy.tems because of the abundant reserves of sodium on ***,anode materials are presently.limited by.low energy.density.poor rate performance and inferior cy.ling *** recent y.ars,tin disulfide(SnS_(2))with a particular lay.red structure has been considered as a promising anode material for SIBs due to its high theoretical capacity.and low ***,a nervoussy.tem-like structured SnS_(2)/CNTs composite was successfully.sy.thesized via a hy.rothermal *** SnS_(2)sheets were strung with carbon nanotubes(CNTs)to form a hierarchical porous structure,which is effective for electroly.e diffusion and electronic *** large distance of the(001)plane(0.5899 nm)of SnS_(2)favors Na+insertion-extraction *** from these structural characteristics,SnS_(2)/CNTs electrodes exhibit high specific capacity.excellent rate performance and superior cy.ling stability.A high charge capacity.of 642 mAh·g^(-1)was released at 0.2 A·g^(-1),and then,a high reversible capacity.of 427 mAh·g^(-1)was retained after 100 *** charged at 2 A·g^(-1),the SnS_(2)/CNTS electrode maintained a capacity.of 282 mAh·g^(-1).The nervous-sy.tem-like structure of the SnS_(2)/CNTs composite provides a novel strategy.for the development of SIBs with high electrochemical performance.

关键词： SnS_(2)/CNTs Sodium-ion batteries Anode Composite Rate capability