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Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-feng Yang Hai-feng song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

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Phase Transformation and Carbide Precipitation of Functional Gradient Semi-solid 9Cr18 Steel

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 823-830页

作者： Yong-Jin Wang Ren-Bo song Ren-feng song School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Institute of Industrial Science The University of TokyoKomaba 4-6-1MeguroTokyo 153-8505Japan Ansteel Mining Engineering Corporation Anshan 114004China

The unique phase transformation and carbide evolution in 9Cr18 steel were investigated during semi-solid forming and subsequent heat treatment. The functional gradient thixoforging 9Cr18 component was divided into inner area and edge area. Microstructure evolution was different at each area. After semi-solid cooling, the solid particles in the inner area were retained as meta-austenite. During annealing, M_（23）C_6 carbide began to precipitate when temperature reached 700 °*** transformation occurred when temperature reached 800 °C. The occurrence of M_（23）C_6 carbide and martensite structure would be harmful to the mechanical properties of inner area. In the edge area, the liquid underwent eutectic transformation to form bar-shape M_7C_3 carbide and secondary austenite after semi-solid cooling. The width of bar-shape carbide would decrease during annealing. By controlling the carbide evolution, we could tailor the functional gradient material with required property.

关键词： Semi-solid forming Solid/liquid phase Annealing Carbide precipitation

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Dominance property based tabu search for single machine scheduling problems with family setups

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1233-1238页

作者： Jin feng song Shiji Wu Cheng Dept. of Automation Tsinghua Univ. Beijing 100084 P. R. China

The problem of minimizing the maximum lateness on a single machine with family setups is *** solve the problem, dominance property is studied and then introduced into the tabu search（TS） *** the dominance property, most unpromising neighbors can be excluded from the neighborhood, which makes the search process always focus on the most promising areas of the solution *** proposed algorithms are tested both on the randomly generated problems and on the real-life *** results show that the proposed TS algorithm outperforms the best existing algorithm and can solve the real-life problems in about 1.3 on average.

关键词： single machine family setups tabu search dominance property.

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Erosion corrosion of low-alloy wear-resistant steels in alkaline slurry

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Journal of Iron and Steel Research International 2017年第10期24卷 1065-1072页

作者： feng-ming song Lin-xiu Du State Key Laboratory of Rolling Technology and Automation Northeastern UniversityShenyang 110004LiaoningChina

Erosion corrosion causes significant problems in various industrial environments through a synergistic effect which results in much greater weight loss than the sum of the weight losses in the individual *** erosion-corrosion behavior of three low-alloy steels was investigated in a simulated concrete slurry using the rotation *** key influencing factors and mechanism of material degradation were *** experimental results indicate that the weight loss increases with the linear velocity according to a nearly exponential relationship（W =KV^n）,where nis *** weight loss is mainly caused by erosion in the alkaline slurry,and steels with higher tensile strengths show higher erosion-corrosion *** formation of many platelets and ring cracks and their removal from the sample surface during erosion corrosion in the slurry are thought to constitute the mechanism responsible for this weight *** platelets and ring cracks are formed by solid particles striking the sample *** are initially produced and subsequently disappear as they grow and come in contact with each *** craters were observed on the surfaces of samples that exhibited higher weight *** surface of the material became work-hardened because of the effect of the particles striking and scratching,and a deformed layer was produced on the surface for steels of lower strengths,leading to deeper and more abundant gouges.

关键词： Erosion Corrosion Slurry Synergy Steel

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Theoretical calculation and experimental study on the interaction mechanism between TKX-50 and AP

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Defence Technology（防务技术） 2020年第4期16卷 825-833页

作者： Jun Tao Xiao-feng Wang Kun Zhang Xue-song feng The Second Department Xi'an Modern Chemistry Research InstituteXi'an 710065China

The combination of 5,5'-bistetrazole-1,1'-diolate(TKX-50) and ammonium perchlorate(AP) can make greater use of the chemical energy of TKX-50 based energetic *** research on the interaction mechanism between TKX-50 and AP is very important for designing TKX-50-AP compounds and judging the formation feasibility of composite particles,which can lay a theoretical foundation for the preparation of TKX-50-AP mixed crystals and the application of TKX-50 in propellant,propellant and ***,in order to research the interaction mechanism between TKX-50 and AP,density-functional theory calculation was applied to optimize three configurations of TKX-50-AP *** geometry structure,electrostatic potential and binding energy of the compounds were predicted,and the electronic density topological analysis was also carried *** TKX-50-AP mixed crystals structures were constructed,and the radial distribution function of H-O and H-N in mixed crystals was ***,solvent/non-solvent method was applied to prepare TKX-50-AP composites,and the infrared spectro scopy and the non-isothermal decomposition perfo rmance of the composites were *** show that the superposition of positive charges in TKX-50 molecule and negative charges in AP makes the electrostatic potential distributions of TKX-50-AP compounds different from that of TKX-50 and *** interaction energies of TKX-50-AP 1,TKX-50-AP 2 and TKX-50-AP 3 are 39.743 kJ/mol,61.206 kJ/mol and 27.702 kJ/mol,*** interaction between TKX-50 molecules and AP molecules in TKX-50-AP mixed crystals both depends on hydrogen bonds and van der Waals force,and the number and strength of hydrogen bonds are significantly greater than that of van der Waals *** composition of AP and TKX-50 makes the absorption peak of the five-membered rings and NH_3 OH^+ of TKX-50 shift to low wavenumber in the infrared *** general,TKX-50 interacts with AP via hydrogen bonds and va

关键词： 5,5'-bistetrazole-1,1'-diolate Ammonium perchlorate Density-functional theory Molecular dynamics Hydrogen bond

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Origin of the spatial consistency of summer precipitation variability between the Mongolian Plateau and the mid-latitude East Asian summer monsoon region

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Science China Earth Sciences 2020年第8期63卷 1199-1208页

作者： Jie CHEN Wei HUANG Qiong ZHANG song feng Key Laboratory of Western China s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Department of Physical Geography and Bolin Centre for Climate Research Stockholm UniversityStockholm 10691Sweden Department of Geosciences University of ArkansasFayetteville 72701USA

The Mongolian Plateau(MP) is located in the eastern part of arid Central Asia(ACA). Climatically, much of the MP is dominated by the westerly circulation and has an arid and semi-arid climate;however, the eastern part of the MP is also influenced by the East Asian summer monsoon(EASM) and has a humid and semi-humid climate. Several studies have shown that precipitation variability in the MP differs from that in western ACA but is consistent with that in the EASM region. Here we use monthly precipitation data for 1979–2016 to characterize and determine the origin of the summer precipitation variability of the MP and the EASM region. The results show that the MP and the mid-latitude EASM region exhibit a consistent pattern of precipitation variability on interannual and decadal timescales;specifically, the consistent regions are the MP and North and Northeast China. We further investigated the physical mechanisms responsible for the consistent interdecadal precipitation variability between the MP and the mid-latitude EASM region, and found that the mid-latitude wave train over Eurasia, with positive(negative) geopotential height anomalies over the North Atlantic and ACA and negative(positive) geopotential height anomalies over Europe and the MP, is the key factor responsible for the consistency of precipitation variability in the MP and the mid-latitude EASM region. The positive anomalies over the North Atlantic and ACA and negative anomalies over Europe and the MP would enhance the transport of westerly and monsoon moisture to the MP and North and Northeast China. They could also strengthen the Northeast Asian low, enhance the EASM, and trigger the anomalous ascending motion over the MP which promotes precipitation in the MP and in the mid-latitude EASM region. Overall, our results help explain the spatial variations of paleo-precipitation/humidity reconstructions in East Asia and clarify the reasons for the consistency of the regional climate.

关键词： Mongolian Plateau Mid-latitude EASM region Summer precipitation Decadal Consistent variability

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Refill Friction Stir Spot Welding of Similar and Dissimilar Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 30-42页

作者： Xiao-song feng song-Bin Li Li-Na Tang Hui-Min Wang Shanghai Aerospace Equipments Manufacturer Co. LtdShanghai 200245China National Center for Materials Service Safety University of Science and TechnologyBeijingBeijing 100083China

Refi ll friction stir spot welding,also known as friction spot welding(FSpW),is a solid-state welding process suitable for spot joining of lightweight *** the eff orts of improving joint quality for similar and dissimilar materials,for example,aluminum and magnesium,this joining technology is well *** joining mechanism and process characteristics of FSpW have been widely ***,the application of FSpW in industry has not been entirely *** this review article,the research of similar and dissimilar material joints,such as,Al/Cu,Al/Ti,Al/Mg and Al/Steel,is *** microstructural features and mechanical properties of the joints,welding tool and the application development are discussed in detail.

关键词： Refill friction stir spot welding Dissimilar joints Microstructure Mechanical properties Welding parameters

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SORPTION AND DESORPTION CHARACTERISTICS OF CADMIUM BY FOUR DIFFERENT SOILS IN NORTHEAST CHINA

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Chinese Geographical Science 2005年第4期15卷 343-347页

作者： ZHANG Lei song feng-bin Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 P. R. China The Geograte School of Chinese Academy of Sciences Beijing 100039 P. R. China

Four soils, phaeozem (PM), saline-alkali soil (SA), meadow albic bleached soil (MA) and dark brown forest soil (DB) from Northeast China were used to examine the sorption and desorption characteristics of Cd and pH influence on it. According to sorption experiment without pH control, the order of amount of absorbed Cd by soils was: SA>PM>DB>MA. The results from non-linear fitting method showed that Langmuir and Freundrich models were more adaptable than Temkin model in describing the sorption data. The maximum sorption amounts from Langmuir model were: PM>SA>MA>DB. Exponential equation for PM and SA and quadratic equation for MA and DB were suitable to fit the desorption data. The order of average desorption percentage was: MA>DB>PM>SA. The amounts of sorption by PM, DB and MA reached the maximum in pH 9.0, while sorption by SA was linearly increased in the experimental range of pH 3.3-11.4. In uniform pH, however, Cd sorption by SA was the minimum among four soils, which indicated that the more amounts of Cd absorbed by SA in isotherm sorption were ascribed to the higher soil pH. The higher sorption of Cd in PM resulted from the higher percentage of organic matter and clay components.

关键词： cadmium soil sorption desorption Northeast China

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Genome-wide SNP markers provided insights into the reproductive strategy and genetic diversity of the green tide causative species Ulva prolifera in China

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Journal of Oceanology and Limnology 2024年第2期42卷 533-543页

作者： song SUN Weiwei MA Nan WANG song feng Yan SUN CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China Jiaozhou Bay Marine Ecosystem Research Station Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Ulva prolifera is the causative species of the annually occurring large-scale green tides in China since *** specific biological features on reproductivity strategies,as well as intra-species genetic diversity,are still largely unknown,especially at the genome level,despite their importance in understanding the formation and outbreak of massive green *** the present study,the restriction site-associated DNA genotyping approach(2b-RAD)was adopted to identify the genome-wide single-nucleotide polymorphisms(SNPs)of 54 individual thalli including samples collected from Subei Shoal in 2019 and Qingdao coast from 2019 to *** genotype results revealed that most of the thalli in 2019 and 2020 were haploid gametophytes,while only half of the thalli were gametophytes in 2021,indicating flexibility in the reproductive strategies for the formation of the green tides among different years and the dominance of asexual and vegetative reproductive mode for the floating ***,population analysis was conducted,and it revealed a very low genetic diversity among samples from Subei Shoal and the Qingdao coast in the same year and a higher divergence among samples in different *** results showed the efficiency of 2b-RAD in the exploration of SNPs in *** and provided the first genome-wide scale evidence for the origin of the large-scale green tides on the Qingdao *** study improved our understanding of the reproductive strategy and genetic diversity of the green tide causative species and will help further reveal the biological causes of the green tide in China.

关键词： green tide Ulva prolifera 2b-RAD single-nucleotide polymorphism(SNP) reproductive strategy genetic diversity

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Bioavailability of crops to environmental hormone Pb in soils and its remediation

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Chinese Journal Of Geochemistry 2008年第1期27卷 41-45页

作者： KUANG Shaoping song feng Qingdao University of Science and Technology Qingdao 266042 China

Lead (Pb), as an environmental hormone, acts as an estrogen in animal and human bodies, and its envi- ronmental pollution can result in many procreant anomalies, such as maladjustment of incretion, weakening of pro- creation function and descending of genital immunity. Experiments on pot-growth of paddies and corns in this study indicated that these crops did not show any macro-toxic symptoms in the observed contents of Pb added (0–4000 mg/kg) in soils. However, lead in soils can be easily absorbed by crops and accumulated in the different parts of plants. Statistical analysis showed that Pb contents in the crops are strongly positively correlated to the Pb contents in soils. In the crops, the Pb contents of roots are highest, tens to thousands of times those of straws and seeds. It is suggested that the root is a barrier of Pb absorbed by straws and seeds. Based on this fact, Pb pollution in soils can be gradually reduced by planting crops and subsequently removing the roots from the soil. This biotechnology may be used in environmental remediation, which embraces the quality of sustainable agricultural economy and a healthy environment.

关键词：生物利用度环境系统铅化合物

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