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Forensic isoscapes based on intra-individual temporal variation of δ^(18)O and ^(206)Pb/^(207)Pb in human teeth

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Forensic Sciences Research 2021年第1期6卷 42-52页

作者： Laura A.Regan Nathan w.Bower Samuel J.Brown Craig C.Lundstrom Gideon Bartov Matthew D.Cooney Office of Net Assessment Department of DefenseWashingtonDCUSA Chemistry and Biochemistry Department Colorado CollegeColorado SpringsCOUSA Geology Department University of IllinoisUrbanaILUSA Information Technology Services Colorado CollegeColorado SpringsCOUSA

Isotopic signatures used in the georeferencing of human remains are largely fixed by spatially distinct geologic and environmental ***,location-dependent temporal changes in these isotope ratios should also be considered when determining an individual’s provenance and/or *** of the relevant isotopes can be impacted by predictable external factors such as climate change,delocalisation of food and water sources and changes in sources and uses of *** Multi-Collector Inductively-Coupled Plasma Mass Spectrometer(MC-ICP-MS)analyses of ^(206)Pb/^(207)Pb in tooth enamel and dentin from a population of 21±1-year-old individuals born circa 1984 and isotope ratio mass spectrometry(IRMS)of δ^(18)O in their enamel,we examined the expected influence of some of these *** resulting adjustments to the geographic distribution of isotope ratios(isoscapes)found in tooth enamel and dentin may contain additional useful information for forensic identification,but the shifts in values can also impact the uncertainty and usefulness of identifications if they are not taken into account.

关键词： Forensic sciences dentin enamel environmental geolocation isoscape radiogenic and stable isotopes

碳纤维复合材料电火花加工(EDM)机理究研

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航空学报 1991年第12期12卷 B651-B654页

作者：王珉 w.S.Lau 南京航空学院香港理工学院

应用于航空航天技术的碳纤维复合材料具有相当高的比强度、高弹性模量、重量轻、热膨胀小、以及具有导电性、对酸、碱有机溶剂有很大的耐蚀性等诸多的优点。但由于材料本身为纤维织物的层压浸渍结构,使其在切削加工时难于达到较高的光... 详细信息

应用于航空航天技术的碳纤维复合材料具有相当高的比强度、高弹性模量、重量轻、热膨胀小、以及具有导电性、对酸、碱有机溶剂有很大的耐蚀性等诸多的优点。但由于材料本身为纤维织物的层压浸渍结构,使其在切削加工时难于达到较高的光洁度与精度,

关键词：碳纤维复合材料电火花加工

Static Softening Behaviour of Hot-worked Austenite in Microalloyed Structural Steel StE460

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 35-43页

作者： Fuming wang Li Tang J -J. Esser w Bleck (Applied Science School, University of Science and Technology Beliing, Beliing 100083, China)(Paashihua Steelworks, Sichuan 617000, China)(Aachen University of Technology, Germany Applied Science School University of Science and Technology Beijing Beijing 100083 China Panzhihua Steelworks Sichuan 617000 China Aachen University of Technology Germany

Double-hit compression tests were performed on StE460 steel containing microalloying elements niobium and vanadium over a range of temperatures and strain rates penment to hot rolling. The fractional softening was evaluated by use of the offset method, which was confirmed to be a very reasonable method. Appropriate expressions are given for the static recrystallization kinetics as a function of temperature and strain rate. Particular attention is paid to the effect of strain rate on static recrystallization. It can be shown that the static softening is apparently accelerated by strain rate. Recrystallization in low temperature austenitic region is stopped due to precipitation of carbonitrides of microalloying elements, which is reflected in the form of a plateau in the curves of static softening.

关键词： microalloying elements precipitation of carbonitrides static softening

Net primary production in three bioenergy crop systems following land conversion

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Journal of Plant Ecology 2014年第5期7卷 451-460页

作者： Michael w.Deal Jianye Xu Ranjeet John Terenzio Zenone Jiquan Chen Housen Chu Poonam Jasrotia Kevin Kahmark Jonathan Bossenbroek Christine Mayer Department of Environmental Sciences University of Toledo2801 West Bancroft StreetMail Stop 604ToledoOH 43606USA Great Lakes Bioenergy Research Center Michigan State University164 Food Safety and Toxicology BuildingEast LansingMI 48824USA w.K.Kellogg Biological Station Michigan State University3700 East Gull Lake DriveHickory CornersMI 49060USA

Aims Identifying the amount of production and the partitioning to above-and belowground biomass is generally the first step toward select-ing bioenergy *** are very few existing studies on the dynamics of production following land *** objectives of this study were to(i)determine the differences in aboveground net primary production(ANPP),belowground net primary produc-tion(BNPP),shoot-to-root ratio(S:R)and leaf area index in three bioenergy crop systems and(ii)evaluate the production of these three systems in two different land use *** This investigation included biometric analysis of NPP on three agri-cultural sites converted from conservation reserve program(CRP)management to bioenergy crop production(corn,switchgrass and prairie mix)and three sites converted from traditional agriculture production to bioenergy crop *** findings The site converted from conventional agriculture produced smaller ANPP in corn(19.03±1.90 standard error[SE]Mg ha^(−1) year^(−1))than the site converted from CRP to corn(24.54±1.43 SE Mg ha^(−1) year^(−1)).The two land conversions were similar in terms of ANPP for switchgrass(4.88±0.43 SE for CRP and 2.04±0.23 SE Mg ha^(−1) year^(−1) for agriculture)and ANPP for prairie mix(4.70±0.50 SE for CRP and 3.38±0.33 SE Mg ha^(−1) year^(−1) for agriculture).The BNPP at the end of the growing season in all the bioenergy crop systems was not significantly different(P=0.75,N=8).

关键词： bioenergy crops land use change net primary production aboveground net primary production belowground net primary production

Comparing the Effectiveness of Coatings on Carbide andCermet Cutting Tool Inserts

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Journal of Materials Science & Technology 1995年第4期11卷 269-275页

作者： K.H. w.Seah M.Rahman and C.H.Lee (Dept. of Mech. & Prod. Eng., National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511 T.N.Goh (Dept. of Ind. & Sys. Eng., National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511) National Univ of Singapore Singapore

A series of metal cutting experiments was performed on a CNC lathe to evaluate the performance of various coatings on different tool substrates. The workpiece material was plain medium carbon steel and the cutting tool materials were carbide and cermet inserts coated with various single as well as multilayer coatings. Machining was done under various cutting conditions of speed and feed-rate, and for various durations of Cutting. The output parameters studied were the cutting forces (axial, radial and tangential), the surface roughness of the workpiece, as well as the tool wear (crater and flank wear). From these results, the performances of the various cutting inserts are evaluated and compared. Results show that cutting forces are significantly lower when using coated cermets than when using coated carbides although different coatings on the same substrate also result in different cutting forces. However, there is less difference in the surface roughness of the finished workpiece for the various coatings and substrates.

关键词： Tool Comparing the Effectiveness of Coatings on Carbide andCermet Cutting Tool Inserts

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足趾分节及趾骨骨骺变异

人类学学报 1989年第3期8卷 284-287页

作者：于桂英 w.B.wood 山东医科大学澳大利亚昆士兰大学

足趾分节及趾骨骨骺变异,早在19世纪就被人们注意。欧美及日本对二节趾骨的变异都有过报道(Ellis,1980)。wood(1980)也曾发现巴布亚新几内亚人中第5趾为二节趾骨的变异有区域性特点。对趾骨骨骺的变异,文献较少。Venning(1956,1961a)曾... 详细信息

足趾分节及趾骨骨骺变异,早在19世纪就被人们注意。欧美及日本对二节趾骨的变异都有过报道(Ellis,1980)。wood(1980)也曾发现巴布亚新几内亚人中第5趾为二节趾骨的变异有区域性特点。对趾骨骨骺的变异,文献较少。Venning(1956,1961a)曾提到锥型和非锥型骨骺在趾骨上的分布及其与趾骨长度的关系。lachman(1953)曾对假型骨骺的形状及形成过程进行过分析。为了从形态上进一步探讨趾骨骨骺变异特点及其分布规律,本文进行了以下研究。

关键词：足趾分节趾骨骨骺变异

The transcription factor PU.1 promotes alternative macrophage polarization and asthmatic airway inflammation

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分子细胞生物学报:英文版 2015年第6期7卷 557-567页

作者： Feng Qian Jing Deng Yong Gyu Lee Jimmy Zhu Manjula Karpurapu Sangwoon Chung Jun-Nian Zheng Lei Xiao Gye Young Park John w.Christman School of Pharmacy Engineering Research Center of Cell&Therapeutic AntibodyMinistry of EducationShanghai Jiao Tong UniversityShanghaiChina Department of Internal Medicine Section of PulmonaryAllergyCritical Careand Sleep MedicineThe Ohio State UniversityColumbusUSA Department of Physiology and Biophysics College of MedicineUniversity of Illinois at ChicagoChicagoUSA Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy Cancer InstituteXuzhou Medical CollegeXuzhouChina Department of Medicine Section of PulmonaryCritical Careand Sleep MedicineUniversity of Illinois at ChicagoChicagoUSA

The transcription factor PU.1 is involved in regulation of macrophage differentiation and ***,the role of PU.1 in alternatively activated macrophage(AAM)and asthmatic inflammation has yet been *** we report that PU.1 serves as a critical regulator of AAM polarization and promotes the pathological progress of asthmatic airway *** response to the challenge of DRA(dust mite,ragweed,and Aspergillus)allergens,conditional PU.1-deficient(PU/ER(T)^(+/-))mice displayed attenuated allergic airway inflammation,including decreased alveolar eosinophil infiltration and reduced production of IgE,which were associated with decreased mucous glands and goblet cell *** reduced asthmatic inflammation in PU/ER(T)^(+/-) mice was restored by adoptive transfer of IL-4-induced wild-type(wT)***,after treating PU/ER(T)^(+/-) mice with tamoxifen to rescue PU.1 function,the allergic asthmatic inflammation was significantly *** vitro studies demonstrate that treatment of PU.1-deficient macrophages with IL-4 attenuated the expression of chitinase 3-like 3(Ym-1)and resistin-like molecule alpha 1(Fizz-1),two specific markers of AAM *** addition,PU.1 expression in macrophages was inducible in response to IL-4 challenge,whichwas associated with phosphorylation of signal transducer and activator of transcription 6(STAT6).Furthermore,DRAchallenge in sensitized mice almost abrogated gene expression of Ym-1 and Fizz-1 in lung tissues of PU/ER(T)^(+/-) mice compared with wT *** data,all together,indicate that PU.1 plays a critical role in AAM polarization and asthmatic inflammation.

关键词： PU.1 alternatively activated macrophage asthmatic inflammation Th2 IL-4

EFFECTS OF HIGH-DENSITY CURRENT PULSES ON wORK HARDENING BEHAVIORS OF AUSTENITE STAINLESS STEEL IN wIRE-DRAwING DEFORMATION

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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 341-346页

作者： K.F. Yao, P. Yu, J. wang, w. Fang and M.X. Zheng Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

The influence of high-density pulsing current on the work-hardening behaviour of H0Cr17Ni6Mn3 and 1Cr18Ni9 stainless steels in wire-drawing deformation processes has been studied. It was found that the drawing stress and the work-hardening rate of wires were significantly reduced by applying current pulses in drawing process. The work-hardening behavior of the multi-courses drawing deformation can be well described by Hollomon formula σ=κΕn. with the application of current pulses in drawing deformation, the work-hardening exponents of H0Cr17Ni6Mn3 steel wires and 1Cr18Ni9 stainless steel wires were reduced by 33% and 45%, respectively, and their work-hardening coefficients were reduced by 41% and 47%, respectively. It was also found that the work-hardening coefficient of wires was reduced with the increment of the frequency of current pulses, while the work-hardening exponents of both steels were insensitive to the pulsing frequency.

关键词： Deformation Electric currents Pulsatile flow Strain hardening wire drawing

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南极洲高原介绍

天文学报 2006年第4期47卷 407-409页

作者： J.w.V.Storey School of Physics university of New South Wales Sydney NSW 2052Australia

南极洲高原的天文开发在过去的10年中有了显著的进展．大的天文设施已在南极(South Pole)的Amundsen-Scott站运行,更具威力的望远镜已在计划或正在那儿建设,然而由于一些重要的原因,高原站址冰穹A(Dome A)和冰穹C(Dome C)对多种天文学... 详细信息

南极洲高原的天文开发在过去的10年中有了显著的进展．大的天文设施已在南极(South Pole)的Amundsen-Scott站运行,更具威力的望远镜已在计划或正在那儿建设,然而由于一些重要的原因,高原站址冰穹A(Dome A)和冰穹C(Dome C)对多种天文学科似乎比南极更具有利条件．2005年1月中国对冰穹A的成功考察,加上2005年以整年运行为目的的法/意Concordia站在冰穹C的开启,已为南极洲天文学创造了激动人心的新机遇．

关键词：地球南极洲,选址