检索结果-南通市图书馆

Science China Earth Sciences 2014年第2期57卷 323-336页

作者： SHANG YanJun PARK Hyeong-Dong YANG ZhiFa CHEN SiGuang LIN DaMing Key Laboratory of Engineering Geomechancis Institute of Geology and GeophysicsChinese Academy of Sciences Department of Energy Systems Engineering Seoul National University Institute of Cultural Relics Preservation of Yinxian County

This paper is to present an efficient approach to enriching the quantification model of human-riverine interactions and its anthropogenic impact by a retrospective study on one of the four most famous historical hydraulic projects in China,the Tuoshan *** was constructed in 833 AD and had trajectories of natural resilience and hydraulic engineering maturity more than thousand *** historical data and maturation procedure of the hydraulic system were used judiciously to examine the spatial patterns of the long-term water conservancy system with agriculture,urbanization and civilization of Ningbo City in Zhejiang Province,Southeast *** framework is assessed from historical perspective and the deposition rate(DR)is calculated by analyzing the continuous increase of the Tuoshan Weir *** results show that the declining DR during the 1180 years guaranteed the beneficial role the Tuoshan Weir played in spite of some negative river responses caused by the increase of sediment deposition and decrease of fresh water-retention *** following up revamped workings and well matured hydraulic system around the Tuoshan Weir also contribute a lot to the designed mission of the *** conclude that hydraulic system maturation is very important for the proper function and life span of huge hydraulic projects.

关键词： Tuoshan Weir flooding saline water intrusion deposition rate historical hydraulic engineering system

Investigation on the deposition rate and the dilution ratio of plasma surface welding

在线全文

学校读者我要写书评

暂无评论

China Welding 2002年第1期11卷 55-58页

作者：王红英赵昆程志国杨世彦董祖珏 Shenzhen Polytechnic Shenzhen 518055 Harbin Research Institute of Welding Harbin 150080 Harbin Institute of Technology Harbin 150001

A new kind of plasma technology with both high deposition rate and low dilution ratio was developed under the calculation and analysis of the arc flame characteristics of plasma arc,the kinematics behavior of powder and powder's heating in the arc. Compared with normal plasma surfacing method, the idea using constricting nozzle with small orifice diameter, long plasma arc and increasing the distance from meeting point of the two beams of powder to workpiece, to achieve the goals of high deposition rate and low dilution ratio, was put forward here. In order to prove this idea, a set of experimental system was built up and obtained satisfied results including high deposition rate(more than 25 kg/h )and low dilution ratio(less than 5%). The success of this study offers a promising prospect for developing the powder plasma surface welding in China and may open a way to improve this technology further in efficiency and quality.

关键词： plasma surface welding deposition rate dilution ratio

Influence of deposition rate on the structural, optical and electrical properties of electron beam evaporated SnO_2 thin films for transparent conducting electrode applications

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2018年第8期39卷 20-26页

作者： Nitin Kumar Bhawana Joshi K.Asokan Department of Applied Physics Gautam Buddha University Materials Science Division Inter University Accelerator Centre

The role of deposition rate in the structural, optical and electrical properties of SnOthin films deposited by electron beam evaporation method is investigated by varying the deposition powers viz. 50, 75, and 100 *** structural characterization of the films is done by X-ray diffraction(XRD) technique. The surface morphology of the films is studied by scanning electron microscopy(SEM). Rutherford back scattering(RBS) measurements revealed the thickness of the films ranging from 200 nm to 400 and also a change in the concentration of oxygen vacancies which is found to be the maximum in the film deposited at the lowest deposition rate. Optical absorption spectrum is recorded using the UV–V is spectroscopy and the films are found to be transparent in nature. A shift in the absorption edge is observed and is attributed to a different level of allowed energy states in conduction band minimum. The Hall effect and electrical measurements show a variation in the carrier concentrations, mobility and resistivity of the films. In order to explore a better compromise in electrical and optical properties for transparent electrode applications, skin depths calculations are also done to find the optimized values of carrier concentration and mobility.

关键词： SnO_2 oxygen vacancies carrier concentration deposition rate electron beam evaporation

Effect of frequency and pulse-on time of high power impulse magnetron sputtering on deposition rate and morphology of titanium nitride using response surface methodology

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2019年第12期29卷 2577-2590页

作者： Saeed GHASEMI Ali Reza FARHADIZADEH Hamid GHOMI Laser and Plasma Research Institute Shahid Beheshti University

Titanium nitride thin films were deposited on silicon by high power impulse magnetron sputtering(HiPIMS)method at different frequencies(162-637 Hz)and pulse-on time(60-322μs).Response surface methodology(RSM)was employed to study the simultaneous effect of frequency and pulse-on time on the current waveforms and the crystallographic orientation,microstructure,and in particular,the deposition rate of titanium nitride at constant time and average power equal to 250 *** crystallographic structure and morphology of deposited films were analyzed using XRD and FESEM,*** is found that the deposition rate of HiPIMS samples is tremendously dependent on pulse-on time and frequency of pulses where the deposition rate changes from 4.5 to 14.5 nm/*** regression equations and analyses of variance(ANOVA)reveal that the maximum deposition rate(equal to(17±0.8)nm/min)occurs when the frequency is 537 Hz and pulse-on time is 212μ*** experimental measurement of the deposition rate under this condition gives rise to the deposition rate of 16.7 nm/min that is in good agreement with the predicted value.

关键词： high powder impulse magnetron sputtering(HiPIMS) titanium nitride response surface methodology(RSM) deposition rate analyses of variance(ANOVA)

Online evaluation of electroless deposition rate by electrochemical noise method

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2019年第8期29卷 1753-1762页

作者： Z.RAJABALIZADEH D.SEIFZADEH A.HABIBI-YANGJEH Applied Chemistry Department Faculty of Basic Science University of Mohaghegh Ardabili

Continuous noise resistance calculation(CNRC)technique was used for online determination of the electroless nickel deposition rate on zirconium pretreated magnesium *** this purpose,the noise resistance(R_n) variation with time was calculated for the pretreated alloy surface in the electroless plating *** CNRC results were described by energy dispersive X-ray spectroscopy(EDS)and scanning electron microscopy(SEM)***,potentiodynamic polarization and gravimetric measurements were used for determination of the electroless deposition rate at the same time period and the results were compared with the CNRC *** Rn variation with plating time shows that the electroless plating consists of different stages with various deposition *** results of the CNRC and polarization methods were not in acceptable agreement due to the limitations of the polarization method for online monitoring of the deposition ***,the results of the gravimetric measurements were in complete agreement with the CNRC technique and so,the CNRC can be considered as suitable tool for online evaluation of the electroless deposition rate.

关键词： magnesium alloy electroless plating deposition rate electrochemical noise SEM EDS

Effect of deposition rate on microstructure and mechanical properties of wire arc additive manufacturing of Ti-6Al-4V components

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2021年第4期28卷 1100-1110页

作者： ZHANG Pei-lei JIA Zhi-yuan YAN Hua YU Zhi-shui WU Di SHI Hai-chuan WANG Fu-xin TIAN Ying-tao MA Song-yun LEI Wei-sheng School of Materials Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Collaborative Innovation Center of Laser Advanced Manufacturing Technology Shanghai 201620China Fraunhofer Institute for Laser Technology ILT Aachen 52074Germany Department of Engineering Lancaster UniversityLancaster LA14YWUnited Kingdom Institute of General Mechanics RWTH Aachen UniversityAachen 52062Germany

Wire arc additive manufacturing(WAAM)is a novel manufacturing technique by which high strength metal components can be fabricated layer by layer using an electric arc as the heat source and metal wire as feedstock,and offers the potential to produce large dimensional structures at much higher build rate and minimum waste of raw *** the present work,a cold metal transfer(CMT)based additive manufacturing was carried out and the effect of deposition rate on the microstructure and mechanical properties of WAAM Ti-6Al-4V components was *** microstructure of WAAM components showed similar microstructural morphology in all deposition *** the deposition rate increased from 1.63 to 2.23 kg/h,the ultimate tensile strength(UTS)decreased from 984.6 MPa to 899.2 MPa and the micro-hardness showed a scattered but clear decline trend.

关键词： wire and arc additive manufacturing titanium alloys cold metal transfer deposition rate

deposition rate and interaction of human-riverine from height increase and permanent function of an 1180 years weir in Southeast China

在线全文

学校读者我要写书评

暂无评论

Deposition rate and interaction of human-riverine from heigh...

Liquid film dryout model for predicting critical heat flux in annular two-phase flow

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

This paper is to present an efficient approach to enriching the quantification model of human-rivcrinc interactions and its anthropogenic impact by a retrospective study on one of the four most famous historical hydraulic projects in China,the Tuoshan *** was constructed in 833 AD and had trajectories of natural resilience and hydraulic engineering maturity more than thousand *** historical data and maturation procedure of the hydraulic system were used judiciously to examine the spatial patterns of the long-term water conservancy system with agriculture,urbanization and civilization of Ningbo City m Zhejiang Province,Southeast *** framework is assessed from historical perspective and the deposition rate(DR)is calculated by anatyzing the continuous increase of the Tuoshan Weir *** results show that the declining DR during the 1180 years guaranteed the beneficial role the Tuoshan Weir played in spite of some negative river responses caused by the increase of sediment deposition and decrease of fresh water-retention *** following up revamped workings and well matured hydraulic system around the Tuoshan Weir also contribute a lot to the designed mission of the *** conclude that hydraulic system maturation is very important for the proper function and life span of huge hydraulic projects.

关键词： Tuoshan Weir flooding saline water intrusion deposition rate historical hydraulic engineering system

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 398-417页

作者： Bo JIAO Li-min QIU Jun-liang LU Zhi-hua GAN Institute of Refrigeration and Cryogenic Engineering Zhejiang University Hangzhou 310027 China

Gas-liquid two-phase flow and heat transfer can be encountered in numerous fields, such as chemical engineering, refrigeration, nuclear power reactor, metallurgical industry, spaceflight. Its critical heat flux (CHF) is one of the most important factors for the system security of engineering applications. Since annular flow is the most common flow pattern in gas-liquid two-phase flow, predicting CHF of annular two-phase flow is more significant. Many studies have shown that the liquid film dryout model is successful for that prediction, and determining the following parameters will exert predominant effects on the accuracy of this model: onset of annular flow, inception criterion for droplets entrainment, entrainment fraction, droplets deposition and entrainment rates. The main theoretical results achieved on the above five parameters are reviewed; also, limitations in the existing studies and problems for further research are discussed.

关键词： Annular two-phase flow Critical heat flux (CHF) Liquid film dryout deposition rate Entrainment rate

Electroless copper plating on microcellular polyurethane foam

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2010年第S1期20卷 283-287页

作者：田庆华郭学益 School of Metallurgical Science and Engineering Central South University

In order to obtain substrates with good conductive foam for high porosity foam metal materials used in the metal electrodes,the technique of electroless copper plating on the microcellular polyurethane foam with pore size of 0.3 mm was *** main factors affecting the deposition rate such as the solution composition,temperature,pH value and adding ultrasonic were *** results show that the optimum process conditions are CuSO4 16 g/L,HCHO 5 mL/L,NaKC4H4O6 30 g/L,Na2EDTA 20 g/L,K4Fe(CN)6 25 mg/L,pH value of 12.5-13.0 and temperature of 40-50℃.Under these technical conditions, the process has excellent bath *** ultrasonic on the process can elevate the deposition rate of copper by 20%-30%.The foam metal material with a porosity of 92.2%and a three-dimensional network structure,was fabricated by electro-deposition after the electroless copper plating.

关键词： electroless copper plating microcellular polyurethane foam deposition rate foam metal material

Multiphonon hopping conduction in carbon-nickel composite films at different deposition time

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2018年第2期37卷 143-147页

作者： Vali Dalouji S.Mohammad Elahi Shahoo Valedbagi Department of Physics Malayer University Plasma Physics Research Center Science and Research BranchIslamic Azad University

In this work, the electrical properties of car- bon-nickel composite films deposited at different time （50-600 s） were investigated. The films were grown by radio frequency magnetron sputtering on glass substrates at room temperature. The electrical conductivity of the films was investigated in the temperature range of 15-500 K. The conductivity data in the temperature range of 400-500 K show the extended state conduction mecha- nism, while the multiphonon hopping （MPH） conduction is found to dominate the electrical transport in the tempera- ture range of 150-300 K. The films deposited at 180 s have the maximum conductivity. The conductivity at T 〈 60 K could be described in terms of variable range hopping （VRH） conduction. The localized state density around Fermi level （N（EF）） at low temperature for the films deposited at 180 s has the minimum value of about 4.02 × 10^21 cm^-***^-1. The average hopping distance （Rhop） for the films deposited at 180 s has the maximum value of about 3.51 × 10^-7 cm.

关键词： Carbon-nickel films deposition time deposition rate Electrical conductivity Activation energy Hopping conductivity