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COMPOSITIOn EFFECT On DRy SLIDInG WEAR BEHAVIORS OF Ti-B-n THIn FILMS

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 300-306页

作者： P.Sit y.H.Lu H.Chen Z.F.Zhou y.G.shen K.y.Li DepartmentofPhysicsandMaterialsScience CityUniversityofHongKongKowloonHongKongChina DepartmentofPhysicsandMaterialsScience CityUniversityofHongKongKowloonHongKongChina／／DepartmentofManufacturingEngineeringg：EngineeringManagementCityUniversityofHongKongKowloonHongKongChina DepartmentofManufacturingEngineering＆EngineeringManagement CityUniversityofHongKongKowloonHongKongChina

Friction and sliding wear behaviour of Ti-B-n coatings against AISI440C steel ba ll and WC-6wt%Co ball were studied by using pin-on-disk tribometer along with mi crostructure characterization using optical microscopy (OM), scanning electron m icroscopy (SEM) and X-ray photoelectron spectroscopy (XPS). It is shown that the wear resistance of film depended on the wear mechanism. In the case of AISI440C steel, adhesive wear were pre-dominant and the wear rate increased sharply to a maximum when n content reach ~38at.%. This might be related to the change of fi lm microstructure and phase configuration, so the least adhesive transfer of tri bo-film was observed. If WC-6wt%Co ball was used, less deformation wear debris w as observed, this was responsible for the rise of wear rate. Despite of differen t wear modes, friction coefficients in both cases were found to depend mainly on the formation and the amount of h-Bn phase. Elemental analysis by energy disper sive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) revealed that oxygen participated in the wear behavior by reacting with films to form the deb ris comprised of various types of Ti oxide including TiO, TiO2 and Ti2O3 , which increased wear resistance.

关键词： dry sliding wear friction coefficient oxidation Ti-B-n wear

Effects of Morphological Integrity of Secondary Feather on Their Drag Reduction in Pigeons

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Journal of Bionic Engineering 2022年第5期19卷 1422-1438页

作者： Qian Li Huan shen Qingfei Han Aihong Ji Zhendong Dai Stanislav n.Gorb Institute of Bio-Inspired Structure and Surface Engineering College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016China Department of Functional Morphology and Biomechanics Kiel UniversityAm Botanischen Garten 924118 KielGermany

Flight feathers of birds interact with the air flow during *** the observed low drag and high lift values at wind speeds from 9.0 to 19.8 m/s can be achieved due to the feather aerodynamics remains *** the present paper,we tested and compared morphological changes,drag reduction and flow visualization results of intact,damaged,and artificial feathers at different wind speeds in a wind *** the analysis of the drag force and resultant force angle,we proved that the integrity of feathers,whose barbs are usually closely interconnected,played an important role in the drag,which potentially triggers excellent drag reduction *** wind tunnel tests indicated that intact secondary feathers had a surprisingly high maximum drag reduction property at v?=?9 m/s compared with the feathers,where the integrity of barbs was *** hook cascades facilitated elasticity under pressure and suitable permeability in an intact feather,when the hooks were *** was indicated that the suitable permeability of intact feathers would prevent flow separation and reduce drag force at low wind speed;at high wind speed,elasticity under pressure and suitable permeability in an intact feather would facilitate strong squeezing effect,helping feathers withstand larger aerodynamic forces to which they might be subjected during *** was revealed that the intact secondary feather is a compromise between strong lift generation and drag reduction,which has a great significance for the bird’s flight.

关键词： Morphological integrity Secondary feather Drag reduction Wind tunnel Smoke visualization Bioinspiration

Electrical and Optical Properties of InGan/AlGan Double Heterostructure Blue Light-Emitting Diodes

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Chinese Physics Letters 2001年第2期18卷 283-285页

作者： shen Bo shi Hong-Tao ZHAnG Rong CHEn Zhi-Zhong ZHEnG you-Dou national Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093

Electrical and optical properties of InGan/AlGan double heterostructure blue light-emitting diodes were *** of the forward bias current-voltage behaviour of the device demonstrated a departure from the Shockley model of a p-n diode,and it was observed that the dominant mechanism of carrier transport across the junction is associated with carrier *** experiments indicated that there was a main emission band around 2.80 eV and a relatively weaker peak at 3.2 eV.A significant blueshift of the optical emission band was observed,which was consistent with the tunnelling character of electrical ***,the degradation in I-V characteristics and the low resistance ohmic short of the device were observed.

关键词： Gan/AlGan Shockley ohmic

Laparoscopic cholecystectomy plus common bile duct exploration for extrahepatic bile duct stones and postoperative recurrenceassociated risk factors

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World Journal of Gastrointestinal Surgery 2024年第11期16卷 3511-3519页

作者： Jia-Hua Liao Ju-shi Li Tie-Long Wang Wen-shen Liu Department of Hepatobiliary Surgery Shaoyang Central HospitalShaoyang 422000Hunan ProvinceChina Department of Organ Transplantation The First Affiliated Hospital of Sun Yatsen UniversityGuangzhou 510080Guangdong ProvinceChina

BACKGROUnD There remain controversies regarding the surgical treatment of extrahepatic bile duct stones(EHBDSs)in clinical *** To explore the curative effect of laparoscopic cholecystectomy(LC)plus common bile duct exploration(CBDE)for the surgical treatment of EHBDSs and to analyze the risk factors that affect postoperative stone *** Eighty-two patients with EHBDSs admitted between March 2017 and March 2023 were *** them,patients treated with open choledocholithotomy plus LC or open cholecystectomy(OC)were set as the control group(n=40),and those treated with LC plus CBDE served as the observation group(n=42).The surgical outcomes of the two groups were compared,the surgical complications and Gas-trointestinal Quality of Life Index(GIQLI)scores were counted,and the one-year prognostic recurrence was *** factors for postoperative re-currence were determined using univariate and multivariate *** The two groups were comparable in the stone residual rate(P>0.05).The ope-ration time(Pntraoperative bleeding(Pnd total complication rate(P=0.005)were lower in the observation group than in the control *** observation group exhibited a marked increase in the GIQLI score,which was higher than the control group(Pne-year recurrence rate was determined in the observation group vs the control group(P=0.027).Sphincter of Oddi dysfunction[odds ratio(OR)=5.712,P=0.007]and the treatment scheme of open choledocholithotomy plus LC or OC(OR=6.771,P=0.008)were the independent risk factors for one-year recurrence in patients after *** LC plus CBDE for patients with EHBDSs can reduce stone residuals,intraoperative bleeding,complications,and postoperative recurrence.

关键词： Laparoscopic cholecystectomy Common bile duct exploration Extrahepatic bile duct stones Stone recurrence

Synthesis and One-dimensional Structure of Cobalt(Ⅱ) Complex [(naOC_2H_5)CoL_2]_n

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Chemical Research in Chinese Universities 2003年第4期19卷 379-382页

作者： LI Ling GU Wen y.n shi-ping CHEnG Peng LIAO Dai-zheng JIAnG Zong-hui shen Pan-wen Department of Chemistry Nankai UniversityTianjin 300071P.R.China

The treatment of bis(2-hydroxybenzyl)-amine(HL) with naOH and Co(Ⅱ)(nO) 2 gives isostructural one-dimensional coordination polymers [(naOC2H5)CoL2]n(1). The cobalt ions have an octahedral geometry and are coordinated by two crystallographically independent ligands which are further linked by μ -O\-\{phenol\} bridged Co and na atoms to give a one-dimentional structure.

关键词： Crystal structure Sodium Cobalt complex One\|dimension Bis(2-hydroxybenzyl)amine

Long-Term Effects of Inorganic and Organic Amendments on Organic Carbon in a Paddy Soil of the Taihu Lake Region,China

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Pedosphere 2011年第2期21卷 186-196页

作者： MA Li y.nG Lin-Zhang XIA Li-Zhong shen Ming-Xing y.n shi-Xue LI y.n-Dong Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Institute of Agricultural Sciences in Taihu Lake Region Jiangsu Academy of Agricultural Science Suzhou 215155 (China) College of Environmental Science and Engineering Yangzhou University Yangzhou 225009 (China)

A long-term experiment set up in 1980 compared the effects of apply.ng manures and chemical fertilizers on a paddy soil in the Taihu Lake region, China. Of the fourteen randomly distributed treatments consisting of different combinations of organic manure, inorganic nitrogen （n）, phosphorus （P）, and potassium （K）, and rice straw, eight were selected for the present study in 2007. Application of organic manure plus straw significantly increased soil organic carbon （SOC） content of the topsoil （0-10 cm） compared to that of chemical fertilizers alone. The content of SOC was relatively stable in the 10-30 cm layer in the chemical fertilizer treatments and in the 20-40 cm layer in the manure treatments. The stable carbon isotope ratio （513C） ranged from -24% to -28% and increased gradually with depth. The content of SOC was significantly （P 〈 0.05） negatively correlated with 513C. In the 0-20 cm layer, the 513C value significantly decreased in the treatments of manure alone （M）, manure and chemical n and P fertilizers （MnP）, manure and chemical n, P, and K fertilizers （MnPK）, manure, rice straw, and chemical n fertilizer （MRn）, and chemical n fertilizer and rice straw （CnR）, as compared with the no-fertilizer control. In the 30-50 cm layer, however, the ratio significantly increased in all the treatments except Treatment CnR. Mineralization of organic C peaked in the first 2-4 d of incubation and gradually leveled off thereafter over the first 3 weeks, being faster in the manure treatments than the chemical fertilizer treatments. The average rate of mineralization varied from 55.36 to 75.46 mL CO2 kg-1 d-1 and that of stable mineralization from 10 to 20 mL CO2 kg-1 d-1. In eight weeks of incubation, cumulative mineralization was always higher in the manure treatments than the chemical fertilizer treatments, being the highest in Treatment MRn. Combined humus in the soil was mainly （over 50%） composed of tightly combined fraction. The loosely combined humus and its ratio o

关键词： chemical fertilizer humus mineralization organic manure stable carbon isotope ratio

Satellite-based detection of 16.76 MeV γ-ray from H-bomb D-T fusion

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nuclear Science and Techniques 2008年第1期19卷 53-57页

作者： CHEnG Jinxing WAnG Lan OUy.nG Xiaoping shi Jianfang ZHAnG Anhui shen Chunxia OUy.nG Maojie nAn Qinliang Institute of Chemical Defence PLA Beijing 102205 China northwest Institute of nuclear Technology Xi＇an 710024 China Academy of Chemical Defence PLA Beijing 102205 China

Based on the high energy γ-ray yield from the H-bomb D-T fusion reaction, it brings forward the idea apply.ng the 16.76 MeV γ-ray to judge whether the H-bomb happens or not, and to deduce the explosion TnT equivalent accurately. The Monte Carlo n-Particle was applied to simulate the high energy γ-ray radiation characteristics reaching the geosynchronous orbit satellite, and the CVD diamond detector suit for the requirements was researched. A series of experiments were carried out to testify the capabilities of the diamond detector. It provides a brand-new approach to satellite-based nuclear explosion detection.

关键词：中子物理金刚石炸弹 D-T融合

High strength-superplasticity combination of ultrafine-grained ferritic steel:The significant role of nanoscale carbides

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Journal of Materials Science & Technology 2021年第24期83卷 131-144页

作者： J.W.Liang y.F.shen R.D.K.Misra P.K.Liaw Key Laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang110004China The State Key Lab of Rolling&Automation Northeastern UniversityShenyang110819China Laboratory for Excellence in Advanced Steel Research University of Texas at El PasoTX79968USA Department of Materials Science and Engineering University of TennesseeKnoxvilleTN37996USA

There is currently a gap in our understanding of mechanisms that contribute to high strength and high plasticity in high strength UFG ferritic steel with nano-size Fe3 C carbides in situations that involve combination of various strain rates and high *** this regard,we describe the mechanistic basis of obtaining high strength-high plasticity combination in an ultrafine-grained(UFG)(~500±30 nm)ferritic steel with nano-size carbides,which sustained large plastic deformation,exceeding 100%elongation at a temperature significantly below 0.5 of the absolute melting point(Tm).To address the missing gap in our knowledge,we conducted a series of experiments involving combination of strain rate and temperature effects in conjunction with electron microscopy and atom probe tomography(APT).Strain rate studies were carried out at strain rates in the range of 0.0017-0.17 s^(-1)and at different temperatures from 25℃to 600℃.Dynamic recrystallization occurred at 600℃,resulting in a significant decrease in yield and tensile ***,the UFG ferritic steels had an advantage in tensile strength(UTS)and elongation-to-failure(εf)at 600℃,especially at strain rate of 0.0017 s^(-1),with high UTSof 510 MPa and excellent low temperature(y(εf=110%).These mechanical properties are significantly superior compared to similar type of steels at identical temperature.A mechanistic understanding of mechanical behavior of UFG ferritic steels is presented by combining the effect of strain rate,temperature,and nano-size carbides.

关键词： UFG ferritic steel Strain rate Temperature nano-size precipitate Low temperature superplasticity

Environmental impacts of domestic resource extraction in China

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Ecosystem Health and Sustainability 2019年第1期5卷 67-78,I0013页

作者： shen Zhao He-Ming Wang Wei-Qiang Chen Dong y.ng Jing-Ru Liu Feng shi State Environmental Protection Key Laboratory of Eco-Industry Northeastern UniversityShenyangChina Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of ScienceXiamenFujianChina Xiamen Key Lab of Urban Metabolism XiamenFujianChina SDAS Key Laboratory of Scientific Decision-Making Institute of Science and Technology for Development of ShandongQilu University of Technology(Shandong Academy of Sciences)JinanChina Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijingChina

Introduction:The rapid development of economy has led to extensive raw material consumption and relevant environmental damage in *** analyze environmental impacts and identify materials resulting in these environmental effects via raw material extraction,we combine economy-wide material flow accounting and life-cycle analysis methods to estimate environmental impacts of Chinese domestic extraction(DE)during the period of 1992–*** relationship between these increasing environmental impacts and Chinese GDP was also explored by decoupling ***:Results show that Chinese DE increased by 372%during 1992–*** global warming potential,abiotic depletion potential,and respiratory inorganics of Chinese DE increased by 195%,46%,and 408%,*** terms of specific materials,extraction of iron ores,gravel and sand,and coal induced the most environmental *** relationship between environmental impacts and Chinese GDP/DE was characterized by relative ***:To minimize the environmental impacts of extraction,we recommend that the Chinese government improve its extraction techniques and reduce excess demand for materials with large extraction such as iron ores,gravel and sand,and *** also recommend researching alternative materials for scarce resources like molybdenum,gold,and fluorite.

关键词： Decoupling analysis economy-wide material flow accounting life cycle assessment environmental impact material flows