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Early Paleogene stratigraphic sequences,mammalian evolution and its response to environmental changes in Erlian Basin,Inner Mongolia,China

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Science China Earth Sciences 2010年第12期53卷 1918-1926页

作者： Christopher K.BEARD daniel l.GEBO Section of Vertebrate Paleontology Carnegie Museum of Natural History4400 Forbes AvenuePittsburghPA 15213USA Department of Anthropology Northern Illinois UniversityDeKalbIL 60115USA

Paleogene strata in the Huheboerhe area,Erlian Basin,Inner Mongolia,China have been subdivided into three lithological units:the Nomogen Formation,the Arshanto Formation,and the Irdin Manha *** least 12 mammal-bearing horizons have been recognized in these formations,of which 4 in the Nomogen Formation,6 in the Arshanto Formation,and 2 in the Irdin Manha *** investigation proved that the "Houldjin Formation" recognized in this area by the Central Asiatic Expeditions(CAE) of the American Museum Natural History in the 1920s is actually the Irdin Manha Formation,while the "Irdin Manha Formation" of CAE is the Arshanto Formation.A recent paleomagnetic study suggests that the upper part of the Nomogen Formation is early Eocene in age and the Arshanto Formation is mainly early Eocene rather than middle Eocene as previously *** Gashatan,Bumbanian,and Arshantan land mammal ages are correlated respectively to the Thanetian,the early Ypresian,and the middle Ypresian through earliest lutetian of the Geological Time *** land mammal ages are also correlated with the late Tiffanian through Clarkforkian,the early Wasatchian,and the middle-late Wasatchian and most of the Bridgerian of the North American land Mammal *** the early Paleogene,the mammalian history of the Erlian Basin was dominated by the appearance of new mammalian families and the replacement of a variety of genera and species,corresponding to the gradual climatic changes during this time *** abrupt emergence of several modern mammalian orders at the beginning of the Eocene is probably related to extreme climatic warming in relation to the Paleocene-Eocene Thermal Maximum.

关键词： Erlian Basin Paleogene mammal faunal turnover biochronology environmental response

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Dispersion and Damage of Carbon Nanotubes in Carbon Nanotube/7055Al Composites During High-Energy Ball Milling Process

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Acta Metallurgica Sinica(English letters) 2021年第2期34卷 196-204页

作者： S.Bi B.l.Xiao z.H.Ji B.S.liu z.Y.liu z.Y.Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Material Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China AVIC Manufacturing Technology Institute Beijing 100024China

High-energy ball milling(HEBM)combined with powder metallurgy route was used to fabricate carbon nanotube(CNT)reinforced 7055 Al *** powder morphology evolution processes(HEBM-1 and HEBM-2)were designed to investigate the dispersion and damage of CNTs during HEBM ***-1 evolution process involved powder fl attening,cold-welding and fracture,while HEBM-2 evolution process consisted of powder fl attening and *** HEBM-1,the repetitive fracture and cold-welding process was effective for dispersing ***,the powder fl attening process in HEBM-2 was unsuccessful in dispersing CNTs due to two reasons:(1)the thickness of fl aky Al powders exceeded the critical value,and(2)the clustered CNTs embedded in fl aky Al powders could not be *** of the broadening of D band and the appearance of a new defect-related D’band,product of I D/I G and full width half maximum of D band,rather than I D/I G,was used to evaluate the actual damage of *** indicates that the damage of CNTs was severe in powder fl attening and fracture stages,while the damage of CNTs was small in powder cold-welding stage.

关键词： Metal matrix composites Carbon nanotubes Powder evolution Dispersion and damage Powder metallurgy

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人表皮生长因子受体2(HER2)低表达和HER2过表达乳腺癌的鉴别：4种MRI扩散模型的比较研究

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国际医学放射学杂志 2024年第3期 379-380页

作者： C.Mao l.Hu W.Jiang Y.Qiu z.Yang Y.liu 余芸菲

摘要目的确定传统扩散加权成像（DWI）、连续时间随机游走（CTRW）、分数阶微积分（FROC）和拉伸指数模型（SEM）在识别乳腺癌的人表皮生长因子受体2(HER2)表达

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Surface deformation-dependent mechanical properties of bending nanowires:an ab initio core-shell model

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 219-232页

作者： Ye XIAO J.SHANG l.z.KOU Chun lI School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China MIIT Key laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an710072China School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbaneQLD4000Australia

An ab initio core-shell model is proposed to evaluate the surface effect in bending nanowires,in which the elastic modulus depends on the surface relaxation and deformation induced by external *** using first-principles calculations based on the density functional theory(DFT),the surface and bulk properties are calculated for Ag,Pb,and Si *** obtained theoretical predictions of the effective Young’s modulus of nanowires agree well with the experimental data,which shows that the fixed-fixed nanowire is stiffened and the cantilevered nanowire is softened as the characteristic size of the cross section ***,the contrastive analysis on the two kinds of nanowires demonstrates that increasing the nanowire aspect ratio would enhance the surface *** present results could be helpful for understanding the size effect in nanowires and designing nanobeam-based devices in nanoelectromechanical systems(NEMSs).

关键词： surface effect density functional theory(DFT) surface relaxation surface stress nanowire

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Production of Carbon Nanotubes over Pre-reduced laCoO_3 Using Fluidized-bed Reactor

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Chinese Chemical letters 2000年第11期11卷 1031-1034页

作者： liu B.C. liang Q. Tang S.H. Gao l.z. zhang B.l. Qu M.z. Yu z.l. Chengdu Inst. of Organic Chemistry Academia Sinica Chengdu 610041 China Nanjing Univ. of Chemical Technology Nanjing 210009 China

Carbon nanotubes were synthesized on a large scale by the catalytic decomposition of hydrocarbons over pre-reduced laCoO3 using a fluidized-bed reactor. Reaction parameters such as reduction temperature, reduction tim... 详细信息

关键词： CNTs Production of Carbon Nanotubes over Pre-reduced laCoO3 Using Fluidized-bed Reactor over

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Snap-through of an elastica under bilateral displacement control at a material point

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Acta Mechanica Sinica 2020年第3期36卷 727-734页

作者： Q.Wang H.l.zou z.C.Deng Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China

Snap-through phenomenon widely occurs for elastic systems,where the systems lose stability at critical *** snapthrough of an elastica under bilateral displacement control at a material point is studied,by regarding the whole elastica as two components,i.e.,pinned-clamped ***,stiffness-curvature curves of two pinned-clamped elasticas are firstly efficiently located based on the second-order mode,which are used to determine the shapes of two *** transformations are used to assemble two components together to form the whole elastica,which reveals four kinds of *** advantage of this way compared with other methods such as the shooting method is that multiple coexisting solutions can be located accurately.O n the load-deflection curves,four branches correspond to four kinds of shapes and first two branches are symmetrical to the last two branches relative to the original *** the bilateral displacement control,the critical points can only appear at saddle-node bifurcations,which is different to that for the unilateral displacement ***,one critical point is found on the first branch and two critical points are found on the secondary *** addition,the snap-through among different branches can be well explained with these critical points.

关键词： Elastica Snap-through Critical points Buckling Displacement control

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Revealing the high-frequency attenuation mechanism of polyurea-matrix composites

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Acta Mechanica Sinica 2020年第1期36卷 130-142页

作者： J.Cheng z.l.liu C.C.luo T.li z.J.li Y.Kang z.zhuang Applied Mechanics laboratory School of Aerospace EngineeringTsinghua UniversityBeijing100084China Key laboratory of Advanced Materials of Ministry of Education Department of Chemical EngineeringTsinghua UniversityBeijing100084China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China

In this paper,a method for analyzing the high-frequency attenuation property of polyurea-matrix composites is developed by combining experimental,computational and theoretical ***,the ultrasonic experimental platform is established by solving the difficulties of high-frequency ultrasonic testing as high-frequency signal distortion,insufficient driving voltage and sampling rate failure,to study the dynamic mechanical properties(1-5 MHz)of pure polyurea and polyurea-matrix ***,the influences of composite parameters including the size and volume fraction of inclusions on wave attenuation performance under different frequencies are obtained and further verified by numerical ***,the contribution of inclusions to the wave attenuation performance is also theoretically *** is found that the increase of inclusion volume fraction and inclusion diameter will increase the attenuation coefficient of the *** the attenuation of composites with the inclusions of a 150-μm diameter and 30%as volume fraction can be 82%higher than pure *** amplifying attenuation effect of inclusions is mainly attributed to the scattering effect,which is verified by comparing numerical and theoretical results.

关键词： Polyurea Viscoelastic Dynamic mechanical properties Ultrasound

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Smoking and prostate cancer survival and recurrence

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Asian Journal of Andrology 2011年第6期13卷 787-788页

作者： Roberto l Muller daniel M Moreira Division of Urologic Surgery Department of Surgery and the Duke Prostate Center Duke University School of Medicine Durham NC 27710 USA Urology Section Veterans Affairs Medical Center Durham NC 27705 USA The Arthur Smith Institute for Urology North Shore Long Island Jewish Health System New Hyde Park NY USA

moking is associated with several major benign and malignant diseases, representing one of the most important modifiable risk factors. Among urothelial neoplasms, smoking is pivotal in tumor carcinogenesis, but its role in prostate cancer is still controversial. Many authors have failed to demonstrate an association between smoking and prostate cancer.

关键词： major enign malignant diseases iagnosis

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CONTROl TECHNIQUES FOR DIGESTION IN BAYER PROCESS

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Acta Metallurgica Sinica(English letters) 2000年第6期13卷 1174-1178页

作者： G.Y.Gan l.z.Wang Pingguo Aluminum Company Pingguo 531400China

The control techniques for indirect heating digestion in Bayer process of alumina production were researched and developed. They include controlling chemical composition of slurry to be digested and controlling digestion status and energy consumption. Very good performances and technical and technical and economical figures for digestion process have been obtained by carefully applying these comprehensive control techniques in Pingguo alumina refinery.

关键词： control technique digestion Bayer process

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A photoluminescence study of plasma reactive ion etching-induced damage in GaN

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Journal of Semiconductors 2014年第11期35卷 16-19页

作者： z.Mouffak A.Bensaoula l.Trombetta ECE Department California State University Physics and ECE Departments University of Houston ECE Department University of Houston

GaN films with reactive ion etching （RIE） induced damage were analyzed using photoluminescence （Pl）. We observed band-edge as well as donor-acceptor peaks with associated phonon replicas, all in agreement with previous studies. While both the control and damaged samples have their band-edge peak location change with temperature following the Varshni formula, its intensity however decreases with damage while the D-A peak increases considerably. Nitrogen post-etch plasma was shown to improve the band edge peak and decrease the D-A peak. This suggests that the N2 plasma has helped reduce the number of trapped carriers that were participating in the D-A transition and made the D°X transition more active, which reaffirms the N2 post-etch plasma treatment as a good technique to heal the GaN surface, most likely by filling the nitrogen vacancies previously created by etch damage.

关键词： GaN etch damage photoluminescence reactive ion etching

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