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Surface morphology and impurity distribution of electron beam recrystallized silicon films on low cost substrates for solar cell absorber

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Rare Metals 2006年第z1期25卷 195-200页

作者： GROMBAll f MüllER j Department of Mikrosystemtechnik Technische Universitt Hamburg-Harburg Hamburg 21073 Germany

A line shaped electron beam recrystallised polycrystalline silicon film on the low cost substrate was investigated for the use of the solar cell absorber. The applied EB energy density strongly influences the surface morphology of the film system. lower EB energy density results in droplet morphology and the rougher SiO2 capping layer due to the low fluidity. With the energy increasing, the capping layer becomes smooth and continuous and less and small pinholes form in the silicon film. Tungstendisilicide (WSi2) is formed at the interface tungsten/silicon but also at the grain boundaries of the silicon. Because of the fast melting and cooling of the silicon film, the eutectic of silicon and tungstendisilicide mainly forms at the grain boundary of the primary silicon dendrites. The SEM-EDX analysis shows that there are no chlorine and hydrogen in the area surrounding a pinhole after recrystallization because of outgassing during the solidification.

关键词： polycrystalline silicon film solar cell recrystallization energy surface morphology outgassing

Effect of airflow on biodrying of gardening wastes in reactors

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journal of Environmental Sciences 2013年第5期25卷 865-872页

作者： f.j.Colomer-Mendoza l.Herrera-Prats f.Robles-Martínez A.Gallardo-Izquierdo A.B.Pia-Guzmn Department of Mechanical Engineering and Construction (Universidad Jaume I)Jaume 1st University.Ave.Sos Baynat s/nCastellón 12071Spain Biotechnology Multidisciplinary Professional Unit (Instituto Politcnico Nacional)National Politechnic Institute.Ave.Acueduct of Guadalupe s/n Barrio la Laguna TicomnGustavo A.Madero 07340Mxico DF.Mxico

Biodrying consists of reducing moisture by using the heat from aerobic *** parameters that control the process are：aeration,temperature during the process,initial moisture of biowaste,and temperature and relative humidity of the input *** mowing and garden waste from the gardens of the University jaume I,Castellón（Spain）were used as a *** was performed in 10 reactors with known air volumes from 0.88 to 6.42 l/（min·kg dry weight）.To promote aeration,5 of the reactors had 15% of a bulking agent *** experiment lasted 20 *** the experiments it was found that the bulking agent led to greater weight ***,the increased airflow rate was not linearly proportional to the weight loss.

关键词： biodrying biowaste stabilization aerobic fermentation bulking agent

ElECTROCHEMICAl NOISE fEATURES Of PURE AlUMINUM DURING PITTING CORROSION IN NEUTRAl NaCl SOlUTION

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Acta Metallurgica Sinica(English letters) 2003年第1期16卷 20-30页

作者： f.H.Cao Z.Zhang Y.l.Cheng j.f.li j.Q.Zhang j.M.Wang C.N.Cao Department of Chemistry Zhejiang UniversityHangzhou 310027China State Key laboratory for Corrosion and Protection of Metals Institute of Metal ResearchThe Chinese Academy of SciencesShenyang 110016China

Spontaneous electrochemical noise (EN) can be a rich source of information concerning the processes simultaneously occurring at a corroding interface. Potential noise fluctuations during the free corrosion of pure aluminum in different concentration of neutral sodium chloride solution are investigated, and the breakdown and restoration of passive metal's film are studied using potentiodynamic scanning (PDS) measurements and electrochemical impedance spectroscopy (EIS) technique. Two capacitance loops are observed in the Nyquist plots in two kinds of concentration, and the corrosion process is under activation control at first, then become diffusion control within the oxide film and corrosion products of (Al(OH)p-mCl-m) accumulated on the surface of the corroding electrode. It is suggested that the pitting corrosion is much easier to occur for pure aluminum in 7.0wt% than in 2.0wt% NaCl solution, and the high concentration of chloride ion in solution inhibits the repassivation of a metastable pit. The corrosion rate deterministic step does not involve Cl-.

关键词： pure aluminum pitting corrosion electrochemical noise electrochemical impedance spectroscopy potentiodynamic scanning

EffECTS Of la ON STRUCTURE AND PROPERTIES Of HEAVY RAIl STEEl

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Acta Metallurgica Sinica(English letters) 2005年第6期18卷 701-706页

作者： C.j. liu M.f. jiang Y.S. Wang j.j. Chen C.l. li Northeastern University Shenyang 110004 China Baotou Iron and Steel Group Gorporation Baotou 014010 Ghina

The mechanisms of la in heavy rail steel were studied by means of experimental measurements, microstructure observation and theoretical analysis in the present work. for heavy rail steel, the state and the content of la were measured, and the mechanisms and the effects of la on sulfide inclusions, microstracture and properties of steel were determined. Strip-like sulfides disappear in heavy rail steel with la/（O＋S）〉3.50, which is shown that the metallurgical function of modifying sulfide inclusions has been achieved by la. la can fine the grain size of the austenite in heavy rail steel. Under the experimental condition, the plasticity and the impacting toughness of heavy rail steel with 0.005wt% la can evidently be improved.

关键词： rare earth heavy rail steel microscopic structure sulfide inclusion,property

The relationship of high-intensity cross-training with arterial stiffness

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journal of Sport and Health Science 2019年第4期8卷 370-375页

作者： jamie f.Burr jenny l.Beck john j.Durocher Department of Human Health and Nutritional Sciences University of GuelphGuelphON NIG 2W1Canada Applied Human Sciences University of Prince Edward IslandCharlottetownPE CIA 4P3Canada Department of Biological Sciences Michigan Technological UniversityHoughtonMI 49931USA

Background'.Central arterial stiffness is a cardiovascular risk factor that can be readily affected through engagement in physical exercise training,with resistance and aerobic exercise having disparate *** the growing popularity of high-intensity cross-training(HICT),little is currently known about the effects of this mixed modality exercise stimulus on arterial ***,the purpose of this study was to characterize the arterial stiffness of habitual HICT participants *** active and sedentary controls using a cross-sectional ***'.A total of 30 participants were recruited:10 middle-aged long-term participants of HICT(Crossfit)and 20 age,sex,and height matched controls(10 recreationally active,10 sedentary).Central and peripheral pulse wave velocities were measured for the carotid-femoral and femoral-dorsalis pedis arterial *** fitness(maximal oxygen uptake,VChmax)was measured and typical exercise participation rates were self-reported for each ***'.HICT participants manifested central pulse wave velocity(PWV)(5.3±1.0 m/s,mean±SD)and VChmax(43±6 ml/kg/min)values nearly identical to active *** active groups had significantly better values than sedentary controls(7.1±1.0 m/s,p≤0.001;and 32±7 ml/kg/min,p=0.01).No differences were observed in peripheral PWV between ***'.Habitual participation in HICT exercise was not associated with increased central nor peripheral arterial ***-term HICT participants presented with similar fitness and arterial stiffness as compared with participants who practiced traditional aerobic *** to sedentary living,HICT may offer musculoskeletal and cardiovascular health benefits without negatively impacting arterial stiffness.

关键词： Circuit training Crossfit Pulse wave velocity Resistance exercise Vascular Weight training

Improvement of Amplitude-Shift-Keying Signal Quality by Employing an Effective Spectrum Equalization Method in a Combined fSK／ASK Modulation Scheme

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Chinese Physics letters 2005年第8期22卷 1948-1950页

作者：忻向军 P.S.André A.l.j.Teixeira 徐重秀 Anaferreira TiagoSilveira P.M.Monteiro f.daRocha j.l.Pinto SchoolofElectronicEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100876//InstituteofTelecommunicationsCampusdeSantiago3810-193AveiroPortugal InstituteofTelecommunications CampusdeSantiago3810-193AveiroPortugal//DepartmentofPhysicsUniversityofAveiroCampusdeSantiago3810-193AveiroPortugal SchoolofElectronicEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100876 InstituteofTelecommunications CampusdeSantiago3810-193AveiroPortugal SiemensSA R.IrmāosSiemensno1Alfragide2720-093AmadoraPortugal InstituteofTelecommunications CampusdeSantiago3810-193AveiroPortugal//DepartmentofElectronicTelecommunicationsUniversityofAveiroCampusdeSantiago3810-193AveiroPortugal

A simple, economical and applicable spectrum equalization method isimplemented by employing a reshaping filter in the combinedfrequency-shift-keying/amplitude-shift-keying modulation scheme to improve the quality ofam... 详细信息

关键词： TRANSMISSION

Sample selection for models to represent ceramic cores fabricated by stereolithography three-dimensional printing

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journal of Materials Science & Technology 2022年第26期121卷 117-123页

作者： X.l.An j.j.liang j.G.li j.W.Chen Y.Z.Zhou X.f.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Space Manufacturing Technology(CAS Key lab) Beijing 100094China

Ceramic cores with good chemical stability and moderate mechanical properties near casting temperatures of 1550℃ for example are used for the manufacturing of internal structures of hollow blades,requiring complex structures and high precision[1–3].However,traditional preparation method based on investment casting is tedious,requiring not only long production cycles but also high cost[4].

关键词： investment printing ceramic

Investigation of Chemical Properties by NMR During the laboratory Aging of Asphalt

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武汉理工大学学报 2010年第17期32卷 43-46页

作者： MA l X WU S P HUANG j f School of Transportation Wuhan University of TechnologyWuhan 430063China Key laboratory of Silicate Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Communications Planning and Design Institute of Hubei Province Wuhan 430051China

In this work,the chemical properties of asphalt were evaluated during the laboratory aging. The rolling thin film oven (RTfO),termed as short-term aging,and pressurized aging vessel (PAV),termed as long-term aging. Tests were used to simulate the laboratory aging of this asphalt. The performance characteristics of asphalt depends the chemical composition of asphalt. NMR spectroscopy enables etailed information about the Carbon-and-hydrogen types of asphalt without separating it into different components. Carbon and proton NMR measurements of asphalt showed that isomerization was the main chemical reactions of hydrocarbon groups following aging. The Corbett fractionation procedure was used to separate fresh and aged asphalts into four generic fractions,namely; asphaltenes,aromatics,resins and saturates were applied to evaluate the chemical changes that occurred during the aging processes.

关键词： asphalt ageing chemical characteristics NMR

INVESTIGATION Of INflUENCE Of HYDROGEN ATTACK ONfATIGUE PROPERTIES Of PRESSURE VESSEl STEElS

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Acta Metallurgica Sinica(English letters) 1998年第2期11卷 141-149页

作者： j.l.li K.f.Wang j.li Z.M.Yao W.Ke fushun Petroleum Inst Fushun China

Influence of hydrogen attack on mechanical and fatigue properties of 1020, 15CrMo and 2.25Cr-1Mo steels has been studied, which were exposed to gaseous hydrogen at pressure of 18MPa and 300-480℃ for up to 480h. The results of fatigue test showed that hydrogen attack (HA) resulted in an obvious change in fatigue properties of 1020 and 15CrMo steels, however, 2.25Cr-1Mo steel showed a lower susceptibility to hydrogen attack due to the addition of Cr and Mo. fatigue crack behaviour for 1020 steel is attributed to hydrogen attack damage and the crack closure induced by the rough cracking surface, which lead to a valley on △Kth～HA% plot. The change in the fatigue behaviour of 15CrMo steel is possibly caused by severe surface decarburization.

关键词： hydrogen attack pressure vessel steel threshold △K value crack closure