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Effect of Heat Treatment on Delayed Fracture Resistance of High Strength Steel 30CrMnSi2NiNb

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Journal of Iron and Steel Research International 2003年第1期10卷 44-48页

作者： WANG Mao-qiu DONG Han HUI Wei-jun CHEN Si-lian WENG Yu-qing Central Iron and Steel Research Institute chinese society for metals

The steel specimens of nominal composition 0.3C-1.0Cr-1.0Mn-2.0Si-1.0Ni-0.04 Nb were quenched and tempered or isothermally quenched from various *** is found that the steel quenched and tempered with a tensile strength of 1 500-1 600 MPa has a KISCC（critical stress intensity factor） value below 15.0 MPa · m1/*** steel isothermally quenched with a tensile strength of 1 350-1 750 MPa has a KISCC value about 20.0 MPa·m1/*** addition,with increase of isothermal quenching temperature,the tensile strength decreases greatly and KISCC value does not pronouncedly *** microstructure of isothermally quenched specimens is composed of bainite and retained *** delayed fracture resistance is dependent on the stability of austenite,which is in turn related to the retained austenite volume fraction and carbon content in austenite.

关键词： high strength steel heat treatment mixed microstructure delayed fracture

Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao Hou Zhiqiang Yu Shefa Chen Lei Liu Yilin Xiao Key Laboratory of Metallogenic Prediction of Nonferrous metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2),similar to those of titanites in eclogite(14.2-16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry

Integrated biomarker response to assess toxic impacts of iron and manganese on deep-sea mussel Gigantidas platifrons under a deep-sea mining activity scenario

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Journal of Oceanology and Limnology 2024年第2期42卷 522-532页

作者： Li ZHOU Mengna LI Zhaoshan ZHONG Minxiao WANG Hao CHEN Chao LIAN Hao WANG Huan ZHANG Lei CAO Chaolun LI Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of chinese Academy of Sciences Beijing 100049China

Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ***,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its *** this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,*** and iron were chosen for their high levels of occurrence within deep-sea *** accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel *** showed that deep-sea mussel *** exhibited a high capacity to accumulate Mn/*** addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea *** integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than ***,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,*** study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.

关键词： mussel metal deep-sea mining biomarker environmental monitoring

Deep eutectic solvent-driven self-assembly of metal mercaptide complexes with enzyme-mimicking activities for detection of uric acid through one-step cascade catalytic reaction

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Green Chemical Engineering 2024年第1期5卷 75-84页

作者： Jean Claude Munyemana Jia Chen Xin Li Yangxia Han Hao Tang Hongdeng Qiu CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of chinese Academy of Sciences Chinese Academy of SciencesBeijing100039China Department of Pharmacy Gansu Provincial HospitalLanzhou730000China

This work presents a generic strategy to create a series of metal mercaptides complexes via coordination selfassembly between transition metals(Mn,Cu,Co,Fe,and Ni)and cysteine(Cys)by forming the sulfur-metal *** strategy involves dissolving metal chlorides and Cys into deep eutectic solvents(DES),followed by the precipitation of metal mercaptides complexes(such as Cys-Mn)by adding water as an antisolvent,where DES serves as the solvent,shape directing,and capping agent,thereby preventing the formation of other metal ***,the prepared complexes possess both laccase and peroxidase-like properties,allowing the design of a technique for the detection of L-3,4-dihydroxyphenylalanine(L-DOPA)and uric acid,*** prepared Cys-Mn can linearly oxidize L-DOPA with its concentrations from 0.1 to 130μM and the detection limit was calculated to be 75.5 n ***,the Cys-Mn can mimic the activity of peroxidase towards oxidization of o-phenylenediamine at neutral p H,allowing single-step and one-pot cascade reactions for visual and fluorometric measurements of uric acid(UA)that could work in the range of 0.2-500μM UA with a detection limit of 0.06μM and 0.054μМ,*** assay was successful in detecting UA in serum and urine samples with relative standard deviation(RSD)ranging from 7.3%to 10.2%and 3.0%-8.5%respectively,suggesting that it may prove useful in medical diagnostic testing.

关键词： Metal-mercaptides Deep eutectic solvents Self-assembly Peroxidase-mimic catalyst Uric acid detection

类嫦娥五号玄武岩的非克里普贡献年轻月球陨石

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Science Bulletin 2024年第5期69卷 601-605页

作者：许晶瑶李秋立路凯李献华 State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Metallogenic Prediction of Nonferrous metals and Geological Environment Monitoring(Ministry of Education) School of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Lunar basalts offer key insights into the magmatic and thermal evolution of the *** constraints deduced from the Apollo and Luna mission samples,as well as lunar meteorites,had previously suggested that lunar volcanism occurred as early as ca.≥4.37 billion years ago(Ga)[1]and ceased around 2.9-2.8 Ga[2],with two major pulses occurring in 3.95-3.58 and 3.38-3.08 Ga[3].But analysis of lunar basaltic samples recently returned by the Chang’e-5 mission reveals 2-billion-year-old volcanism on the Moon,representing the youngest lunar basalts reported to date[4,5].One of the most popular hypotheses for the cause of longlived volcanism on the Moon is that the source region for young lunar volcanism was enriched in radioactive heat-producing elements[2,6].Lunar samples from 3.5 to 3.0 Ga exhibit a gradual increase in the potassium,rare-earth elements,and phosphorus(KREEP)-like component contribution[3],consistent with the radioactive heat-producing elements ***,the demonstrably non-KREEP origin for the 2-billion-year-old Chang’e-5 basalts implies a possible transition in lunar volcanism away from a KREEP-like component contribution occurred between 3.0 and 2.03 Ga[7].Therefore,studying the characteristics and origin of magmatic activity during the period from 3.0 to2.03 Ga is essential to address the timing of the possible transition and to thus extend our understanding of sustaining long-lived volcanism on the ***,this goal is currently hampered by limited available lunar materials.

关键词： magmatic origin basalt

Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to Ag)

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Rare metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng Chao-Nan Cui Zhi-Xun Luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Enhancing multifunctional photocatalysis with acetate-assisted cesium doping and unlocking the potential of Z-scheme solar water splitting

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Carbon Energy 2024年第3期6卷 178-195页

作者： Mengmeng Ma Jingzhen Li Xiaogang Zhu Kong Liu Kaige Huang Guodong Yuan Shizhong Yue Zhijie Wang Shengchun Qu Key Laboratory of Semiconductor Materials Science Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Department of Physics College of Physical Science and TechnologyXiamen UniversityXiamenChina State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijingChina

Graphitic carbon nitride(g-C_(3)N_(4))has been extensively doped with alkali metals to enlarge photocatalytic output,in which cesium(Cs)doping is predicted to be the most ***,the sluggish diffusion and doping kinetics of precursors with high melting points,along with imprecise regulation,have raised the debate on whether Cs doping could make *** this matter,we attempt to confirm the positive effects of Cs doping on multifunctional photocatalysis by first using cesium acetate with the character of easy *** optimized Csdoped g-C_(3)N_(4)(CCN)shows a 41.6-fold increase in visible-light-driven hydrogen evolution reaction(HER)compared to pure g-C_(3)N_(4) and impressive degradation capability,especially with 77%refractory tetracycline and almost 100%rhodamine B degradedwithin an *** penetration ofCs+is demonstrated to be a mode of interlayer doping,and Cs–N bonds(especially with sp^(2) pyridine N in C═N–C),along with robust chemical interaction and electron exchange,are *** atomic configuration triggers the broadened spectral response,the improved charge migration,and the activated photocatalytic ***,we evaluate the CCN/cadmium sulfide hybrid as a Z-scheme configuration,promoting the visible HER yield to 9.02 mmol g^(−1) h^(−1),which is the highest ever reported among all CCN *** work adds to the rapidly expanding field of manipulation strategies and supports further development of mediating served for photocatalysis.

关键词： acetate-assisted cesium doping multifunctional photocatalysis Z-scheme

Dynamic Risk Spillovers in Non-Ferrous Metal Future Markets During COVID-19:A Frequency Domain Analysis

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Journal of Systems Science and Information 2024年第1期12卷 47-63页

作者： Guang YANG Xiaoyu LIU Dingxuan ZHANG Yunjie WEI School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Center for Research on Intelligent Perception and Computing Institute of AutomationChinese Academy of SciencesBeijing 100190China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

During the COVID-19 pandemic,the international financial markets experienced severe *** the background of“Made in China 2025”,substantial entity enterprises have a large demand for non-ferrous *** the enhancement of financial attributes of non-ferrous metals,it is vital to prevent financial systemic risk contagion in the non-ferrous metal *** this article,the ensemble empirical mode decomposition method is used to decompose the prices of eight important non-ferrous metals futures,and then the dynamic DY risk spillover index model is established from the perspectives of long-term and *** risk spillover between non-ferrous metals during the COVID-19 is quantitatively analyzed from different frequency *** study finds that in the long run,the risk spillover relationship between non-ferrous metals remained basically stable,and the change of it after the epidemic is *** the short run,the risk spillover relationship has different degrees of structural changes after the outbreak of the COVID-19 *** ensemble empirical mode decomposition method can distinguish the risk spillovers in different cycles,and help to formulate policies for preventing systemic risks in the non-ferrous metal markets according to the different length of terms.

关键词： COVID-19 non-ferrous metals ensemble empirical mode decomposition risk spillover index

Current-Induced Magnetization Switching Behavior in Perpendicular Magnetized L1_(0)-MnAl/B2-CoGa Bilayer

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chinese Physics Letters 2024年第5期41卷 138-143页

作者：孙宏利韩荣坤秦红蕊赵旭鹏谢志成魏大海赵建华 State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China International School of Microelectronics Dongguan University of TechnologyDongguan 523808China

Rare-earth-free Mn-based binary alloy L1_(0)-MnAl with bulk perpendicular magnetic anisotropy(PMA) holds promise for high-performance magnetic random access memory(MRAM) devices driven by spin-orbit torque(SOT). However, the lattice-mismatch issue makes it challenging to place conventional spin current sources, such as heavy metals, between L1_(0)-MnAl layers and substrates. In this work, we propose a solution by using the B2-CoGa alloy as the spin current source. The lattice-matching enables high-quality epitaxial growth of 2-nm-thick L1_(0)-MnAl on B2-CoGa, and the L1_(0)-MnAl exhibits a large PMA constant of 1.04 × 10^(6)J/m^(3). Subsequently, the considerable spin Hall effect in B2-CoGa enables the achievement of SOT-induced deterministic magnetization switching. Moreover, we quantitatively determine the SOT efficiency in the bilayer. Furthermore, we design an L1_(0)-MnAl/B2-CoGa/Co_(2)MnGa structure to achieve field-free magnetic switching. Our results provide valuable insights for achieving high-performance SOT-MRAM devices based on L1_(0)-MnAl alloy.

关键词： alloy enable holds