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Acta Metallurgica Sinica(English letters) 1998年第6期11卷 477-484页

作者： Q.Gao Y.x.Zhao l.x.cai Southwest Jiaotong Univ Chengdu China

Based on the test results obtained from the single-step test and the incremental-step test at room temperature and 240℃, a probabilistic assessment of temperature effects on the cyclic stress-strum response and the fatigue life of 1Cr18Ni9Ti steel weld metal is performed. In orber to assess the temperature effect on cyclic stress amplitude where there is a scatter of the material cyclic constitution, a probabilistic assessment approach on the basis of probabilistic modified Ramberg-Osgood relations is *** investigation shows that the cyclic stress amplitude and the scatter of cyclic stress amplitude data are decreased at 240℃. Similarly, from the consideration of the fatigue life scatter a probabilistic assessment of temperature effect on the fatigue life is suggested on the basis of probabilistic langer S-N relations. The investigation shows that the crack initiation life is increased and the scatter of crack initiation life data is decreased at 240℃.

关键词： 1Cr_(18)Ni_9Ti stainless steel weld metal low cycle fatigue temperature effect probabilistic assessment

Estimation of J—R Curves for Small-Sized COEC Specimens and Its Application Considering Crack-Tip Cons tr aints

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Acta Mechanica Solida Sinica 2019年第3期32卷 261-276页

作者： G.W.He C.Bao l.x.cai Y.J.Wu Applied Mechanics and Structure Safety Key laboratory of Sichuan Province School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The normalization method has been employed to estimate the J-resistance (J—R) curves for C-shaped outside edge-notched compression (COEC) specimens of SA-508 steel. The COEC specimens present the lowest J—R curves in comparison with other three types of specimens. Based on the J—Q—M met hod, the constraint parame ter Q determined at the mid-plane in the through-thickness direction of the specimen is used to approximately quantify the threedimensional crack-tip constraint for COEC specimens. Combining with the previous experiments on J—R curves, the constraint-coirected J—R curves for SA-508 steel specimens are given, which may be used to predict the fracture toughness of actual cracked components in structural integrity assessment.

关键词： Ductile fracture toughness COEC specimen Dimensionless load separation principle Normalization method Crack-tip constraint J-Q-M method

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： Chaofeng lü Chao Sun Shengqiang cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar

Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.liu l.Deng Q.Wang x.Zhang F.Q.Meng Y.P.Wang Y.Q.Gao H.B.cai S.P.Zhu Graduate School China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Shanghai Institute of laser Plasma Shanghai 201800China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China School of Physics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex-merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BSRS evolution driven by broadband lasers.

关键词： scattering kinetic simplified

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al Neutron Absorbing Materials

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Acta Metallurgica Sinica(English letters) 2024年第8期37卷 1411-1420页

作者： J.x.cai B.M.Shi N.li Y.liu Z.G.Zhang Y.N.Zan Q.Z.Wang B.l.xiao Z.Y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

Optimized silicon fertilization regime weakens cadmium translocation and increases its biotransformation in rice tissues

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The Crop Journal 2024年第4期12卷 1041-1053页

作者： Bogui Pan Yixia cai Kunzheng cai Jihui Tian Wei Wang College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Provincial Key laboratory of Eco-Circular Agriculture Guangzhou 510642GuangdongChina Key laboratory of Tropical Agricultural Environment in South China Ministry of Agriculture and Rural AffairsGuangzhou 510642GuangdongChina College of Agriculture South China Agricultural UniversityGuangzhou 510642GuangdongChina

In acidic paddy fields of South China,rice(Oryza sativa l.)faces the dual challenges of cadmium(Cd)toxicity and silicon(Si)*** previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice,the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain *** study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes:Si(T)(all Si added before transplanting),Si(J)(all Si added at jointing),and Si(TJ)(half Si added both before transplanting and at jointing).The findings revealed that the regime of Si(TJ)was more beneficial to rice health and grain safety than Si(T)and Si(J).The osmotic regulators such as proline,soluble sugars,and soluble proteins were significantly boosted by Si(TJ)compared to other Si treatments,and which enhanced membrane integrity,balanced intracellular pH,and increased Cd tolerance of ***,Si(TJ)was more effective than Si(T)and Si(J)on the Cd sequestration in the cell wall,Cd bio-passivation,and the down-regulated expression of the Cd transport *** concentrations of Cd in the xylem and phloem treated with Si(TJ)were reduced ***,Si(TJ)facilitated much more Cd bound with the outer layer proteins of grains,and promoted Cd chelation and complexation by phytic acid,phenolics,and ***,Si(TJ)outperformed Si(T)and Si(J)in harmonizing the phycological processes,inhibiting Cd translocation,and enhancing Cd detoxification in rice *** the split Si application strategy offers potential for reducing Cd toxicity in rice grain.

关键词： Cadmium Silicon Growth stages Translocation and accumulation Rice Safe production

Iron–doped bismuth oxybromides as visible-light-responsive Fenton catalysts for the degradation of atrazine in aqueous phases

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Journal of Environmental Sciences 2024年第3期137卷 321-332页

作者： Yong-li cai Yu-Hang xu Ji-Zun xiang Zhi-Qiang Zhang Qiu-xiang He Ya-Feng li Jian lü Fujian Provincial Key laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Pesticides and its degradation products,being well–known residues in soil,have recently been detected in many water bodies as pollutants of emerging concerns,and thus there is a contemporary demand to develop viable and cost–effective techniques for the removal of related organic pollutants in aqueous ***,a visible-light-responsive Fenton system was constructed with iron–doped bismuth oxybromides(Fe–BiOBr)as the *** the advantage of sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion and optimized H_(2)O_(2)utilization,the optimal Fe–BiOBr–2 catalyst showed an excellent atrazine removal efficiency of 97.61%in 120 min,which is superior than the traditional homogeneous Fenton and the majority of heterogeneous processes documented in the *** this photo–Fenton system,hydroxyl(·OH)and superoxide(·O_(2)^(-))radicals were dominant active species contributed to the oxidative degradation of *** to the production of various active radicals,five degradation pathways were proposed based on the identification of intermediates and degradation ***,this work not only demonstrates a fundamental insight into creating highly efficient and atom economic photo-Fenton systems,but also provides a complementary strategy for the treatment of organic pollutants in water.

关键词： Bismuth oxybromide Photo–Fenton Atrazine Catalytic degradation

Effects of zeolite imidazole frameworks on rice seedlings (Oryza sativa l.): Phytotoxicity, transformation, and bioaccumulation

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Journal of Environmental Sciences 2024年第10期144卷 15-25页

作者： Chaofa Chen Yongqi Yao Chenghua xing Yunyu Guo luyi cai Jianfang Yan xi-lin Wu Miaozhen cai College of Geography and Environmental Science Zhejiang Normal UniversityJinhuaZhejiang 321004China College of Agriculture Jinhua PolytechnicJinhuaZhejiang 321007China

Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental ***,their environmental fate and potential ecological impact on plants remain ***,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa l.)under hydroponic ***-8 and ZIF-67 in the concentration of 50 mg/l decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,*** scanning electron microscopy(SEM)imaging combined with x-ray diffraction(xRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation *** fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in *** results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and *** so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control *** findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of *** study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.

关键词： Zeolitic imidazolate frameworks (ZIFs) Rice(Oryza sativa l.) Phytotoxicity Transformed ZIFs ZIFs bioaccumulation

A COUPlED METHOD COMBINING CROUZEIx-RAVIART NONCONFORMING AND NODE CONFORMING FINITE ElEMENT SPACES FOR BOIT CONSOlIDATION MODEl

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Journal of Computational Mathematics 2024年第4期42卷 911-931页

作者： Yuping Zeng Mingchao cai liuqiang Zhong School of Mathematics Jiaying UniversityMeizhou 514015China Department of Mathematics Morgan State University1700 E Cold Spring LnBaltimoreMD 21251USA School of Mathematical Science South China Normal UniversityGuangzhou 520631China

A mixed finite element method is presented for the Biot consolidation problem in *** precisely,the displacement is approximated by using the Crouzeix-Raviart nonconforming finite elements,while the fuid pressure is approximated by using the node conforming finite *** well-posedness of the fully discrete scheme is established,and a corresponding priori error estimate with optimal order in the energy norm is also *** experiments are provided to validate the theoretical results.

关键词： Poroelasticity Nonconforming finite element Inf-sup condition A priori error estimate

Heterometallic Mg-Ni-Mg Complex Promoted Hydrosilylation of Alkenes: Catalytic Performance and Intermediates Characterization

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Chinese Journal of Chemistry 2024年第18期42卷 2133-2139页

作者： Yanping cai Shengjie Jiang xin xu Key laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochowUniversitySuzhouJiangsu215123China

Background and Originality Content The catalytic hydrosilylation of unsaturated hydrocarbons,facilitated by transition metal(TM),is widely recognized as a proficient technique for the synthesis of high-value organosilicon compounds'ti-4l over the past few decades,the most dominant *** in hydrosilylation processes have been constituted by pre-Ccious metar complexesroceinerecent vears omore sustainabile earth-abundant metal catalysts have received increased attentionj2-14l The classcal mechanism of transition metal-catalyzed hydrosilylation is generally accomplished through a series of fundamental processes(Scheme 1a),including(i)coordination and oxidative addition of Si-H bond to a low-valent metal center to form e.g.,o-complex or silyl metal hydride;(ii)insertion of.C-C multipe bonds intometal-hdridelsior metal-silicon bond;jiol and(ii)reductive elimination that forwards the hydrosilylated product with Markovnikov or anti-Markovnikov selectivity.

关键词： Heterometallic complex Cooperative effect Hydrosilylation Magnesium Nickel hydride