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Formation of TiAlSi intermetallics during heating Ti-A356 Al mixed powder compact at semisolid temperature

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j.urnal of Materials Science & Technology 2021年第35期94卷 247-263页

作者： M.gao T.j.Chen Z.X.Zhang State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China

Due to the similarity in composition and crystal structure of some Ti Al Si ternary intermetallics,it is quite difficult to accurately confirm their physic characteristics,and thus,to tailor microstructure to improve mechanical properties of metal materials related to the Ti Al Si ***,the formation process of Ti Al Si intermetallics was investigated during heating Ti-A356 mixed powder compact at a A356 alloy semisolid temperature of 595℃.The results indicated that two kinds of intermetallics ofτ1(tetragonal,I41/amd)andτ2(orthorhombic,Cmcm)generated,and both the concentration and supply direction of Ti atoms,which are related to local breakage of oxide films on neighboring Ti and A356 alloy powders,determined the phase and morphology of the intermetallics.τ1 andτ2 crystals all had an intrinsic plate morphology,butτ2 crystals were thinner due to more anisotropic growth resulted from their high density of stacking faults(SFs).τ1 lamellar domains generated during growth ofτ2 crystals,which were accompanied by decrease in density of *** combined effect of size difference and internal energy difference betweenτ1 andτ2 crystals made largeτ1 crystals coarsen at the expense ofτ2 crystals in Ostwald ripening,leading them to finally evolve into an agglomerate of largeτ1 plates.

关键词： Intermetallics Stacking faults Growth Phase transformation

Ecosystem Services of Grazed Grasslands in the Flooding Pampa

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Phyton-International j.urnal of Experimental Botany 2024年第6期93卷 1179-1202页

作者： elizabeth j.j.cobo Adriana M.Rodríguez Facultad de Agronomía Área de AgroecologíaUniversidad de Buenos AiresBuenos Aires1417Argentina Facultad de Agronomía Departamento de Producción AnimalUniversidad de Buenos AiresBuenos Aires1417Argentina

The Flooding Pampa grasslands are the last remnant of the Rio de la Plata grasslands in ***-genic interventions have led to severe degradation and,as a result,the ecosystem services provided by the grass-lands are declining,in terms of provisioning,regulating,and supporting *** synthesized the existing literature on the ecosystem goods and services provided by these grasslands under grazing in different conditions and conservation *** found that plant and animal diversity and primary production are the most studied ecosystem services,while climate regulation,water supply,nutrient cycling,meat production and erosion control,in that order,are less *** services are *** grazing and glyphosate spraying are the main drivers of grassland *** grazing and conservative stocking rates have been shown to reverse degradation and demonstrate that livestock production is compatible with ecosystem conserva-tion by maintaining regulating and provisioning *** these management strategies are poorly integrated,improving their implementation will require important changes in farmers’decisions and the development of policies that create the economic conditions for this to *** is needed to understand the conditions that prevent the knowledge generated from being transferred to producers and translated into practices that would improve the provision of ecosystem services.

关键词： Salado basin sustainability biodiversity rangelands meat production adaptative multi paddock grazing process technologies agroecology

Synthesis, characterization and oxidative activity of heteropolyanion pillared layered compound

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Chinese Science Bulletin 1997年第11期42卷 914-918页

作者： He, QL gao, j.Hu, CW Wang, EB NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

TRANSITION element trisubstituted and Ln bi-（1:11）series heteropolyanion with Keggin struc-ture are excellent catalyst with oxidizing *** they have some shortcomingssuch as poor stability and impossible recycle use when they are used in homogeneous ***（An-）,among hydroxides（LDHS）-like layers,having a general formula[M1-x2+Mx3+-

关键词： heteropolyanion pillared layered compound synthesis oxidative activity.

Impact of source tissue and ex vivo expansion on the characterization of goat mesenchymal stem cells

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j.urnal of Animal Science and Biotechnology 2015年第2期6卷 230-251页

作者： Nuradilla Mohamad-Fauzi Pablo j.Ross elizabeth A Maga j.mes D Murray Department of Animal Science University of California Institute of Ocean and Earth Sciences University of Malaya Department of Population Health and Reproduction University of California

Background： There is considerable interest in using goats as models for genetically engineering dairy animals and also for using stem cells as therapeutics for bone and cartilage repair. Mesenchymal stem cells （MSCs） have been isolated and characterized from various species, but are poorly characterized in goats. Results： Goat MSCs isolated from bone marrow （BM-MSCs） and adipose tissue （ASCs） have the ability to undergo osteogenic, adipogenic and chondrogenic differentiation. Cytochemical staining and gene expression analysis show that ASCs have a greater capacity for adipogenic differentiation compared to BM-MSCs and fibroblasts. Different methods of inducing adipogenesis also affect the extent and profile of adipogenic differentiation in MSCs. Goat fibroblasts were not capable of osteogenesis, hence distinguishing them from the MSCs. Goat MSCs and fibroblasts express CD90, CD105, CD73 but not CD45, and exhibit cytoplasmic localization of OCT4 protein. Goat MSCs can be stably transfected by Nucleofection, but, as evidenced by colony-forming efficiency （CFE）, yield significantly different levels of progenitor cells that are robust enough to proliferate into colonies of integrants following G418 selection. BM-MSCs expanded over increasing passages in vitro maintained karyotypic stability up to 20 passages in culture, exhibited an increase in adipogenic differentiation and CFE, but showed altered morphology and amenability to genetic modification by selection. Conclusions： Our findings provide characterization information on goat MSCs, and show that there can be significant differences between MSCs isolated from different tissues and from within the same tissue. Fibroblasts do not exhibit trilineage differentiation potential at the same capacity as MSCs, making it a more reliable method for distinguishing MSCs from fibroblasts, compared to cell surface marker expression.

关键词： Adipose Bone marrow Characterization Differentiation Goat Mesenchymal stem cells

Sex　Health　Education　in　University

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China Population Today 1997年第2期14卷 17-18页

作者： M j.gao

Nearly 100 students from the Capital Normal University began a course on sex health inform ation six months *** is the first sub-sidiary course in China to specialize in sex health education.

关键词： University Sex Education Health

Oximes： Unrecognized Chameleons in Genera and Specialized Plant Metabolism

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Molecular Plant 2018年第1期11卷 95-117页

作者： Mette S rensen elizabeth H.j. Neilson Birger Lindberg Moiler Plant Biochemistry Laboratory Department of Plant and Environmental Sciences University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark VILLUM Center for Plant Plasticity University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark Center for Synthetic Biology University of Copenhagen Thorvaldsensvej 40 Frederiksberg C Copenhagen Denmark

Oximes （R1R2C=NOH） are nitrogen-containing chemical constituents that are formed in species representing all kingdoms of life. In plants, oximes are positioned at important metabolic bifurcation points between general and specialized metabolism. The maj.rity of plant oximes are amino acid-derived metabolites formed by the action of a cytochrome P450 from the CYP79 family. Auxin, cyanogenic glucosides, glucosinolates, and a number of other bioactive specialized metabolites including volatiles are produced from oximes. Oximes with the E configuration have high biological activity compared with Z-oximes. Oximes or their derivatives have been demonstrated or proposed to play roles in growth regulation, plant defense, pollinator attraction, and plant communication with the surrounding environment. In addition, oxime-derived products may serve as quenchers of reactive oxygen species and storage compounds for reduced nitrogen that may be released on demand by the activation of endogenous turnover pathways. As highly bioactive molecules, chemically synthesized oximes have found versatile uses in many sectors of society, especially in the agro- and medical sectors. This review provides an update on the structural diversity, occurrence, and biosynthesis of oximes in plants and discusses their role as key players in plant general and specialized metabolism.

关键词： structural diversity CYP79 auxin cyanogenic glucosides volatile organic compounds E-oxime Z-oxime

老年人群骨关节疾病流行特征及其影响因素研究

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中国全科医学 2025年第3期28卷 280-284,298页

作者：高焱杨淑显范雷常亮高莉张寒雪李卉康锴河南省疾病预防控制中心慢性非传染性疾病防治研究所河南省郑州市450016

背景骨关节疾病是老年人群常见、多发的慢性疾病,其与更高的死亡率、更多的致残率、功能状态的下降和较低的生命质量显著相关,产生巨大的疾病负担。目前尚无河南省该病流行情况及其影响因素的研究。目的了解河南省老年人群骨关节疾病流... 详细信息

背景骨关节疾病是老年人群常见、多发的慢性疾病,其与更高的死亡率、更多的致残率、功能状态的下降和较低的生命质量显著相关,产生巨大的疾病负担。目前尚无河南省该病流行情况及其影响因素的研究。目的了解河南省老年人群骨关节疾病流行特征及其影响因素,为其实施精准防控提供科学依据。方法采用多阶段随机整群抽样方法,通过调查问卷、医学体检、实验室检测等方法,获取2018年河南省≥18岁常住居民人口学特征、既往疾病史、身体活动及身体指标等,本研究纳入1055名≥60岁居民为研究对象。运用多因素Logistic回归分析探讨河南省不同特征老年人群骨关节疾病特征及其影响因素。结果2018年河南省老年人群骨关节疾病患病率(加权后)为28.13%(95%CI=28.10%~28.15%)。其中女性、城市、超重或肥胖、中心性肥胖、血脂异常或高脂血症、无吸烟史、有打鼾史、中等强度活动的老年人群骨关节疾病患病率更高(P<0.05)。多因素Logistic回归分析显示,男性(OR=0.717,95%CI=0.550~0.933,P=0.013)是老年人群骨关节疾病的保护因素;超重或肥胖(OR=1.329,95%CI=1.050~1.684,P=0.018)、中心性肥胖(OR=1.305,95%CI=1.047~1.626,P=0.018)是老年人群骨关节疾病的危险因素。结论河南省老年人群骨关节疾病与性别、BMI和中心性肥胖相关,应对老年人群中女性、超重或肥胖和中心性肥胖者开展针对性健康教育及综合干预。

关键词：关节疾病骨关节炎骨关节病老年人人口特征影响因素分析河南

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Balancing Frequencies and Fault Detection in the In-Parameter-Order Algorithm

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j.urnal of Computer Science & Technology 2015年第5期30卷 957-968页

作者：高世伟吕江花杜冰磊 Charles j. Colbourn 马世龙 State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China School of Computing Informaties and Decision Systems Engineering Arizona State University Tempe AZ 85287-8809 U.S.A.

The In-Parameter-Order （IPO） algorithm is a widely used strategy for the construction of software test suites for combinatorial testing （CT） whose goal is to reveal faults triggered by interactions among parameters. Variants of IPO have been shown to produce test suites within reasonable amounts of time that are often not much larger than the smallest test suites known. When an entire test suite is executed, all faults that arise from t-way interactions for some fixed t are surely found. However, when tests are executed one at a time, it is desirable to detect a fault as early as possible so that it can be repaired. The basic IPO strategies of horizontal and vertical growth address test suite size, but not the early detection of faults. In this paper, the growth strategies in IPO are modified to attempt to evenly distribute the values of each parameter across the tests. Together with a reordering strategy that we add, this modification to IPO improves the rate of fault detection dramatically （improved by 31% on average）. Moreover, our modifications always reduce generation time （2 times faster on average） and in some eases also reduce test suite size.

关键词： combinatorial testing IPO test suite generation expected time to fault detection software under test

Insights into properties of activated carbons prepared from different raw precursors by pyrophosphoric acid activation

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j.urnal of Environmental Sciences 2016年第3期28卷 235-243页

作者： Yuan gao Qinyan Yue Baoyu gao Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong University

Low-cost activated carbons（ACs） were prepared from four kinds of solid wastes：petroleum coke,Enteromorpha prolifera,lignin from papermaking black liquid and hair,by pyrophosphoric acid（H_4P_2O_7） ***-gravimetric analysis of the pyrolysis of H_4P_2O_7-precursor mixtures implied that H_4P_2O_7 had different influences on the pyrolysis behavior of the four raw materials.N_2 adsorption/desorption isotherms,scanning electron microscopy,Fourier transform infrared spectroscopy and adsorption capacities for dyes were used to characterize the prepared activated *** derived from *** exhibited the highest surface area（1094 m^2/g） and maximum monolayer adsorption capacity for malachite green（1250 mg/g）.Kinetic studies showed that the experimental data were in agreement with the pseudo-second-order *** adsorption isotherms were well described by the Langmuir isotherm model,indicating the adsorption of dye onto the ACs proceeded by monolayers.

关键词： Solid waste Pyrophosphoric acid Low-cost adsorbent Dye Adsorption