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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 710-721页

作者： L.A.Santa-cruz G.Machado A.A.Vicente T.f.c.Hermenegildo T.f.A.Santos Department of Mechanical Engineering Universidade Federal de PernambucoAv.da Arquiteturas/n50740-550RecifePEBrazil center of Nanotechnology Centro de Tecnologias Estratégicas do NordesteCETENERecifePEBrazil Department of chemical Engineering Universidade de Sao PauloSao PauloSPBrazil

The conditions used for friction stir welding of duplex stainless steels determine the resulting mechanical and corrosion performance of the *** study investigates the corrosion resistance of UNS S32750 and S32760 superduplex stainless steels(SDSSs)joined by friction stir welding,employing cyclic polarization,Mott–Schottky,and microscopy techniques for *** microscopy images indicated the presence of a deleterious intermetallic phase after electrolytic etching of S32760,as well as decreased corrosion *** presence of molybdenum in the steels promoted better passive behavior at low *** Mott–Schottky curves revealed p-n heterojunction behavior of the passive *** acquired after the polarization test by scanning electron microscopy showed higher passivation propensity with increases of temperature and pH.

关键词： superduplex stainless steel friction stir welding corrosion resistance cyclic polarization Mott–Schottky

colon cancer and the immune system:The role of tumor invading T cells

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World Journal of Gastroenterology 2006年第45期12卷 7233-7238页

作者： Maximilian Waldner carl c Schimanski Markus f Neurath I. Department of Medicine University of Mainz Mainz Germany

colon cancer is still one of the leading causes of cancer death worldwide. Although the host immune system has been shown to react against tumor cells, mainly through tumor infi ltrating lymphocytes and NK cells, tumor cells may utilize different ways to escape anti-tumor immune response. Tumor infi ltration of cD8+ and cD4+ (T-bet+) effector T cells has been attributed to a beneficial outcome, and the enhancement of T cell activation through T cell receptor stimulation and co-stimulatory signals provides promising strategies for immunotherapy of colon cancer. Growing evidence supports a role for the fas/fasL system in tumor immunology, although the mechanisms and consequences of fasL activation in colon cancer are not completely understood. In animal models, depletion of regulatory T cells (cD4+ cD25+ T cells) can enhance the anti-tumor immune response under certain conditions. Taken together, recent insights in the immune reaction against colon carcinoma have provided new approaches to immunotherapy, although much remains to be learned about the exact mechanisms.

关键词： cD4-positive T-lymphocytes cD8-positive T-lymphocytes Immunology colonic neoplasms therapy colorectal neoplasms Humans Lymphocytes Tumor-infiltrating Tumor escape

Hack's law of debris-flow basins

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International Journal of Sediment Research 2009年第1期24卷 74-87页

作者： LEE c. f BEIGHLEY R. E Department of civil Engineering The University of Hong Kong Pokfulam Road 2. Director Soil Erosion Research Laboratory Department of civil Construction and Environmental Engineering San Diego State University

Hack’s law was originally derived from basin statistics for varied spatial scales and regions. The exponent value of the law has been shown to vary between 0.47 and 0.70,causing uncertainty in its application. This paper focuses on the emergence of Hack’s law from debris-flow basins in china. Over 5,000 debris-flow basins in different regions of china with drainage areas less than 100km2 are included in this study. Basins in the different regions are found to present similar distributions. Hack’s law is derived from maximum probability and conditional distributions,suggesting that the law should describe some critical state of basin evolution. Results suggest the exponent value is approximately 0.5. further analysis indicates that Hack’s law is related to other scaling laws underlying the evolution of a basin and that the exponent is not dependent on basin shape but rather on the evolutionary stage. A case study of a well known debris-flow basin further confirms Hack’s law and its implications in basin evolution.

关键词： Debris-flow basins Hack’s law Scaling laws Basin evolution

Nanocrystalline Ti49.2Ni50.8 shape memory alloy as orthopaedic implant material with better performance

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Journal of Materials Science & Technology 2019年第10期35卷 2156-2162页

作者： H.f.Li f.L.Nie Y.f.Zheng Y.cheng S.c.Wei R.Z.Valiev Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 700877China center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Department of Oral and Maxillofacial Surgery School of StomatologyPeking UniversityBeijing 100081China Institute of Physics of Advanced Materials Ufa State Aviation Technical UniversityUfaRussia Saint Petersburg State University Universitetskiy prospekt 28PeterhofSt.Petersburg198504Russia

Ti Ni alloys, with their unique shape memory effects and super elastic properties, occupy an indispensable place in the family of metallic biomaterials. In the past years, surface treatment is the main technique to improve the bioinert nature of microcrystalline Ti Ni alloys and inhibit on the release of toxic nickel ions to obtain excellent osteogenesis and osseointegration function. In the present study, nanocrystalline Ti49.2Ni50.8 alloy has been fabricated via equal channel angular pressing(EcAP), and the in vitro and in vivo studies revealed that it had enhanced cell viability, adhesion, proliferation, ALP(Alkaline phosphatase)activity and mineralization, and increased periphery thickness of new bone, in comparison to the commercial coarse-grained counterpart. These findings indicate that the reduction of grain size is beneficial to increasing the biocompatibility of Ti49.2Ni50.8 shape memory alloy.

关键词： Nanocrystallines Shape memory alloys Metallic biomaterials Orthopaedic implants TiNi alloys

VARIATION Of PHYSIcO-cHEMIcAL PROPERTIES Of RADIATION cROSSLINKED RUBBER WITH STORAGE TIME

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chinese Journal of Polymer Science 2005年第5期23卷 497-501页

作者： N.c.Dafader M.E.Haque f.Akhtar Nuclear and Radiation chemistry Division

The effect of storage on physico-chemical properties of non-irradiated natural rubber and radiation vulcanized natural rubber （RVNR） were evaluated. The rubber films were stored under two different conditions, namely in open air and sealed polyethylene bags. The antioxidant, tris（nonylated phenyl） phosphite （TNPP） was used for preventing degradation of RVNR films. Gel content, cross-link density, tensile strength at break and 500% elongation of rubber films were measured. The results show that the retention （%） of tensile properties of rubber films with TNPP is higher than that of rubber films without antioxidants. The rubber films stored in polyethylene bags also show better retention of tensile properties than those of rubber films stored in open air.

关键词： Storage Radiation Tensile Properties Antioxidant.

Subaqueous early eruptive phase of the late Aptian Rajmahal volcanism,India:Evidence from volcaniclastic rocks,bentonite,black shales,and oolite

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Geoscience frontiers 2017年第4期8卷 809-822页

作者： Naresh c.Ghose Nilanjan chatterjee Brian f.Windley G/608 Raheja ResidencyKoramangala Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technology Department of Geology The University of Leicester

The late Aptian（118-115 Ma） continental flood basalts of the Rajmahal Volcanic Province（RVP） are part of the Kerguelen Large Igneous Province,and constitute the uppermost part of the Gondwana Supergroup on the eastern Indian shield *** lower one-third of the Rajmahal volcanic succession contains thin layers of plant fossil-rich inter-trappean sedimentary rocks with pyroclasts,bentonite,grey and black shale/mudstone and oolite,whereas the upper two-thirds consist of sub-aerial fine-grained aphyric basalts with no inter-trappean *** the eastern margin and the north-central sector of the RVP,the volcanics in the lower part include rhyolites and dacites overlain by enstatite-bearing basalts and *** pyroclastic rocks are largely felsic in composition,and comprise ignimbrite as well as coarse-grained tuff with lithic clasts,and tuff breccia with bombs,lapilli and ash that indicate explosive eruption of viscous rhyolitic *** rhyolites/dacites（〉68 wt.%） are separated from the andesites（〈 60 wt.%） by a gap in silica content indicating their formation through upper crustal anatexis with only heat supplied by the basaltic *** the other hand,partially melted siltstone xenoliths in enstatite-bearing basalts suggest that the enstatite-andesites originated through mixing of the upper crust with basaltic magma,crystallizing orthopyroxene at a pressure-temperature of ~3 kb/1150℃.In contrast,the northwestern sector of the RVP is devoid of felsic-intermediate rocks,and the volcaniclastic rocks are predominantly mafic（basaltic） in ***,the presence of fine-grained tuffs,tuff breccia containing sideromelane shards and quenched texture,welded tuff breccia,peperite,shale/mudstone and oolite substantiates a subaqueous *** on these observations,we conclude that the early phase of Rajmahal volcanism occurred under predominantly subaqueous *** presence of grey and black shale/mudstone in the lower one-third of

关键词： Rajmahal basalt Andesite Rhyolite Pyroclast Black shale Oolite

STUDY ON THE PROPERTIES Of BLEND Of NATURAL RUBBER LATEX/METHYL METHAcRYLATE GRAfTED RUBBER LATEX BY GAMMA RADIATION

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chinese Journal of Polymer Science 2007年第5期25卷 519-523页

作者： N.c. Dafader M.E. Haque f. Akhtar Nuclear and Radiation chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （MMA） grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from co-60 source at room temperature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. Modulus increases from 6.99 MPa to 9.87 MPa for an increase in proportion of MMA grafted rubber from 40% to 60% in the blend at similar absorbed dose. Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost flat.

关键词： Natural rubber latex MMA grafted rubber latex Blend rubber Irradiation cross-link.

Sensitivity of the Simulation of Tropical cyclone Size to Microphysics Schemes

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Advances in Atmospheric Sciences 2016年第9期33卷 1024-1035页

作者： Kelvin T.f.cHAN Johnny c.L.cHAN School of Energy and Environment City University of Hong Kong

The sensitivity of the simulation of tropical cyclone （Tc） size to microphysics schemes is studied using the Advanced Hurricane Weather Research and forecasting Model （WRf）. Six Tcs during the 2013 western North Pacific typhoon season and three mainstream microphysics schemes-ferrier （fER）, WRf Single-Moment 5-class （WSM5） and WRf Single-Moment 6-class （WSM6）-are investigated. The results consistently show that the simulated Tc track is not sensitive to the choice of microphysics scheme in the early simulation, especially in the open ocean. However, the sensitivity is much greater for Tc intensity and inner-core size. The Tc intensity and size simulated using the WSM5 and WSM6 schemes are respectively higher and larger than those using the fER scheme in general, which likely results from more diabatic heating being generated outside the eyewall in rainbands. More diabatic heating in rainbands gives higher inflow in the lower troposphere and higher outflow in the upper troposphere, with higher upward motion outside the eyewall. The lower-tropospheric inflow would transport absolute angular momentum inward to spin up tangential wind predominantly near the eyewall, leading to the increment in Tc intensity and size （the inner-core size, especially）. In addition, the inclusion of graupel microphysics processes （as in WSM6） may not have a significant impact on the simulation of Tc track, intensity and size.

关键词： tropical cyclone microphysics size intensity track numerical modelling

The inception of a Paleotethyan magmatic arc in Iberia

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Geoscience frontiers 2015年第2期6卷 297-306页

作者： M.f.Pereira A.castro c.fernández IDL Departamento de Geociências ECT Universidade de évora Departamento de Geología Universidad de Huelva Departamento de Geodinámica y Paleontología Universidad de Huelva

This paper presents a compilation of recent U-Pb （zircon） ages of late carboniferous-early Permian （Lc EP） calc-alkaline batholiths from lberia, together with a petrogenetic interpretation of magma generation based on comparisons with Mesozoic and Tertiary cordilleran batholiths and experimental melts. Zircon U-Pb ages distributed over the range ca. 315-280 Ma, indicate a linkage between calc-alkaline magmatism, Iberian orocline generation and Paleotethys subduction. It is also shown that Iberian Lc-EP calcalkaline batholiths present unequivocal subduction-related features comparable with typical cordilleran batholiths of the Pacific Americas active margin, although geochemical features were partially obscured by local modifications of magmas at the level of emplacement by country rock assimilation. When and how Lc-EP calc-alkaline batholiths formed in Iberia is then discussed, and a new and somewhat controversial interpretation for their sources and tectonic setting （plume-assisted relamination） is suggested. The batholiths are proposed to have formed during the subduction of the Paleotethys oceanic plate （Pangaea self-subduction） and, consequently, they are unrelated to Variscan collision. The origin of the Iberian batholiths is related to the Eurasian active margin and probably represents the inception of a Paleotethvan arc in the core of Pangaea.

关键词： Permo-carboniferous calc-alkaline arc-related batholiths Pangaea Paleotethys subduction Variscan and cimmerian cycles

Experimental Podophyllotoxin (Bajiaolian) Poisoning:——Ⅱ. Effects on the Liver, Intestine, Kidney, Pancreas and Testis

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Biomedical and Environmental Sciences 1992年第4期5卷 293-302页

作者： LOUISW.cHANG c.M.YANG c.f.cHEN J.f.DENG Departments of Pathology Pharmacology and Toxicology University ora rkansas for Medical Sciences Little RockThe Chang-Gung Medical College Kwai-sanNational Research Institute of Chinese MedicineThe Veteran's General Hospital-Taipei AR 72205TaipeiTaipeiTaipei Taiwan China

Young male rats were orally intubated with podophyllotoxin: Group I, control animals, orally fed with vehicle only; Group Ⅱ, fed with an initial dose of 5 ***-1 b.w., followed by a daily dose of 1.67 mg-kg-1 b.w. for 7d. Group III, fed with an initial dose of 15 ***-1 b.w., followed by a daily dose of 5 ***-1 b.w. for 7d. All animals were sacrificed 72 h after the last dosing.Histopathological examination revealed dose-related fatty change of the liver, atrophy andi degenerative changes of the intestinal epithelial linings and testicular seminiferous tubules. Depletion of the pancreatic acinar cell granules was also apparent in the Group III animals. No pathology, however, was observed in the kidneys. The present study demonstrated for the first time degenerative changes in the liver, intestine, testis, and pancreas of animals ingested podophyllotoxin. These pathological changes correlate well with the clinical signs/symptoms of abnormal liver function, abdominal pain and diarrhea, and reduced serum amylase in humans poisonded by podophyllum. Inhibition of protein synthesis and mitosis (disruption of microtubules) are believed to be the underlying mechanisms of these changes observed in the animals intoxicated by. podophyllotoxin.

关键词： Bajiaolian Effects on the Liver Experimental Podophyllotoxin Kidney Poisoning