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可编程可集成光电混合液晶编码32比特加法器模块 被引量:1
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作者 余飞鸿 吴平凡 郑国武 《半导体光电》 CAS CSCD 北大核心 1993年第3期269-274,共6页
本文分析了脉动进位全加器进行叠代所需要的总位数和总次数,在此基础上,研究了液晶编码来实现逻辑运算的基本结构,设计了液晶编码光电混合32比特半加器模块及构成全加器所需要的电子学反馈系统,最后给出了实验结果。
关键词 液晶编码 加法器 可编程 可混合
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Capacity of Mixed Traffic Flow Crossing Multi-Major-Lanes 被引量:2
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作者 李文权 王炜 周刚 《Journal of Southeast University(English Edition)》 EI CAS 2000年第2期100-104,共5页
Based on the gap acceptance theory, the mixed traffic flow composed of r representative types of vehicles 1, 2,…, r vehicles is analyzed with probability theory. Capacity model of the minor mixed traffic flow ... Based on the gap acceptance theory, the mixed traffic flow composed of r representative types of vehicles 1, 2,…, r vehicles is analyzed with probability theory. Capacity model of the minor mixed traffic flow crossing m major lanes with M3 distributed headway on the unsignalized intersection is set up, and it is an extension of capacity model for one minor lane vehicle type crossing one major lane traffic flow. 展开更多
关键词 M3 distribution HEADWAY gap acceptance traffic flow capacity
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Separation of inhomogeneous blended seismic data 被引量:2
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作者 刘强 韩立国 +2 位作者 陈竞一 陈雪 张显娜 《Applied Geophysics》 SCIE CSCD 2015年第3期327-333,466,共8页
The frequencies of sources involved m conventional blended acquisition are the same. Each source transmits the full frequency band, and in general, significant effort is required to successfully produce and operate wi... The frequencies of sources involved m conventional blended acquisition are the same. Each source transmits the full frequency band, and in general, significant effort is required to successfully produce and operate wideband sources. To solve this problem, inhomogeneous blended or decentralized blended acquisition is used, in which the dominant frequency and bandwidth of the source units in a blended array are not equal. When the inhomogeneous and conventional blending acquisitions adopt the same geometry and separation methods, the former has low signal-to-blending noise ratio. Therefore, we present a new separation method for such blended acquisition based on the synchrosqueezed wavelet transform. The proposed method offers better separation quality and decreases the computation time to approximately 1/3. 展开更多
关键词 Inhomogeneous blended acquisition synchrosqueezed wavelet transform deblending
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Reliability Analysis of a Mixed Redundant Model in C 3I System 被引量:1
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作者 徐勇 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期324-330,共7页
Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute s... Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute system. The reliability and availability equations of MRM were deduced. Results and Conclusion Compared with several other reliability models, it has obvious effect upon improving the system reliability. The effect? cost rate is very high among these models. The model can be used in reliability design, evaluation and check of C 3I system. Only a little attached cost is needed to improve C 3I system reliability effectively. 展开更多
关键词 C 3I system reliability analysis mixed redundant model
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Solving Navier-Stokes equation by mixed interpolation method 被引量:1
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作者 万水 Mogens Peter Nielsen 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期93-95,共3页
The operator splitting method is used to deal with the Navier-Stokes equation, in which the physical process described by the equation is decomposed into two processes: a diffusion process and a convection process; a... The operator splitting method is used to deal with the Navier-Stokes equation, in which the physical process described by the equation is decomposed into two processes: a diffusion process and a convection process; and the finite element equation is established. The velocity field in the element is described by the shape function of the isoparametric element with nine nodes and the pressure field is described by the interpolation function of the four nodes at the vertex of the isoparametric element with nine nodes. The subroutine of the element and the integrated finite element code are generated by the Finite Element Program Generator (FEPG) successfully. The numerical simulation about the incompressible viscous liquid flowing over a cylinder is carded out. The solution agrees with the experimental results very well. 展开更多
关键词 Navier-Stokes equation finite element method incompressible viscous flow mixed interpolation method
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HYBRID SCHEME FOR COMPRESSIBLE TURBULENT FLOW AROUND CURVED SURFACE BODY
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作者 许常悦 冉倩 孙建红 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第4期315-323,共9页
A hybrid central-upwind scheme is proposed. Two sub-schemes, the central difference scheme and the Roets flux difference splitting scheme, are hybridized by means of a binary sensor function. In order to examine the c... A hybrid central-upwind scheme is proposed. Two sub-schemes, the central difference scheme and the Roets flux difference splitting scheme, are hybridized by means of a binary sensor function. In order to examine the capability of the proposed hybrid scheme in computing compressible turbulent flow around a curved surface body, especially the flow involving shock wave, three typical eases are investigated by using detached-eddy simulation technique. Numerical results show good agreements with the experimental measurements. The present hybrid scheme can be applied to simulating the compressible flow around a curved surface body involving shock wave and turbulence. 展开更多
关键词 detached-eddy simulation shock wave compressible turbulence hybrid scheme
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Precise Calculation System of Total Mix Ration for Lactating Cow 被引量:1
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作者 杨亮 熊本海 +1 位作者 罗清尧 杨琴 《Agricultural Science & Technology》 CAS 2012年第12期2569-2576,共8页
[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and pr... [Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and protein system (CNCPS) with integrating dynamic prediction models on main nutrient requirements of dairy cattle recommended by NRC (2001) and the CNCPS parameter database accumu- lated by Chinese feed database, the ration nutrient requirement dynamic calculation and total mixed ration (TMR) formula optimizing system for Holstein dairy cow was developed using FOXPRO database system and parametric linear programming algo- rithm. [Result] By optimizing a specific cow ration and analyzing its completed nutri- ents, the results showed that this system could entirely consider a lots of nutrient balances, such as concentrate fraction and forage fraction balance, rumen degrad- able protein and rumen undergradable protein balance, crude protein and lactation net energy balance, fibrous substances (ADF, NDF) and non-fiber carbohydrates (NFC) balance, calcium and phosphate balance, electrolytes balance and trace ele- ment balance etc., and could also calculate intestinal amino acid flow in terms of different models. [Conclusion] By using dynamic mathematical equations and comput- erized program, it can be realized for the ration formula design of lactating cow with all-round interoperable but mutual-constraining each other among ration nutrients. 展开更多
关键词 Holstein dairy cattle Total mixed diet Formula model Metabolic protein Linear programming
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Explosion limits for combustible gases 被引量:10
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作者 TONG Min-ming WU Guo-qing HAO Ji-fei DAI Xin-lian 《Mining Science and Technology》 EI CAS 2009年第2期182-184,共3页
Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that... Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that these limits are related to the concentrations of different components in the mixture. With an increase of C4H10 and C6H14, the Lower ExplosionLimit (LEL) and Upper Explosion-Limit (UEL) of a combustible gas mixture will decrease clearly. For every 0.1% increase in C4H10 and C6H14, the LEL decreases by about 0.19% and the UEL by about 0.3%. The results also prove that, by increasing the amount of H2, the UEL of a combustible gas mixture will increase considerably. If the level of HE increases by 0.1%, the UEL will increase by about 0.3%. However, H2 has only a small effect on the LEL of the combustible gas mixture. Our study provides a theoretical foundation for judging the explosion risk of an explosive gas mixture in mines. 展开更多
关键词 coal mine GAS explosive gases explosion limits
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Reliability analysis of earth slopes using hybrid chaotic particle swarm optimization 被引量:7
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作者 M.Khajehzadeh M.R.Taha A.El-Shafie 《Journal of Central South University》 SCIE EI CAS 2011年第5期1626-1637,共12页
A numerical procedure for reliability analysis of earth slope based on advanced first-order second-moment method is presented,while soil properties and pore water pressure may be considered as random variables.The fac... A numerical procedure for reliability analysis of earth slope based on advanced first-order second-moment method is presented,while soil properties and pore water pressure may be considered as random variables.The factor of safety and performance function is formulated utilizing a new approach of the Morgenstern and Price method.To evaluate the minimum reliability index defined by Hasofer and Lind and corresponding critical probabilistic slip surface,a hybrid algorithm combining chaotic particle swarm optimization and harmony search algorithm called CPSOHS is presented.The comparison of the results of the presented method,standard particle swarm optimization,and selected other methods employed in previous studies demonstrates the superior successful functioning of the new method by evaluating lower values of reliability index and factor of safety.Moreover,the presented procedure is applied for sensitivity analysis and the obtained results show the influence of soil strength parameters and probability distribution types of random variables on the reliability index of slopes. 展开更多
关键词 reliability analysis stability assessment earth slopes particle swarm optimization harmony search
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Flow pattern visualization and nonlinear analysis of gas-liquid mixing process with top-blowing gas stirring 被引量:4
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作者 YANG Kai WANG Shi-bo +2 位作者 ZHU Xiu-le XU Jian-xin WANG Hua 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2029-2040,共12页
The evaluation of the mixing effect of gas-liquid two-phase flow during the top-blown gas agitation mixing is one of the difficulties in the testing field, especially in the process of using the model method to study ... The evaluation of the mixing effect of gas-liquid two-phase flow during the top-blown gas agitation mixing is one of the difficulties in the testing field, especially in the process of using the model method to study the metallurgical top-blowing process. In order to evaluate the effect of gas-liquid two-phase flow mixing, a gas chromatography simulation based on capacitance tomography was used to visualize the flow pattern and analyze the mixed characteristics. A gas top-blown agitation test rig was set up, the gas phase was air-selected, and the liquid phase was selected from synthetic heat-conducting oil. The top-blown stirring test process was measured and imaged by electrical capacitance tomography (ECT) equipment from ECT Instruments Ltd (UK). The MATLAB program was used to identify the mixing areas of the images to obtain the distribution of gas-liquid two-phase. The flow pattern of the gas-liquid mixing region was obtained. The chaotic detection of the gas-liquid mixing process was performed by the three-state test method;the images were processed by the counting box dimension-corrosion method to obtain the mixing uniformity time of gas-liquid flow. Results show that it is feasible to use the capacitance tomography technique to visualize the gas-liquid two-phase distribution. The uniformity time quantification of the gas-liquid mixing process is also achieved. 展开更多
关键词 TOP-BLOWING electrical capacitance tomography gas-liquid mixing VISUALIZATION three-state test mixing uniformity time
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Ultra-High Strength Concrete Mixtures Using Local Materials 被引量:6
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作者 Srinivas Allena Craig M. Newtson 《Journal of Civil Engineering and Architecture》 2011年第4期322-330,共9页
This paper presents the development of ultra high strength concrete (UHSC) using local materials. UHSC mixture proportions were developed using local materials so that UHSC may be made more affordable to a wider var... This paper presents the development of ultra high strength concrete (UHSC) using local materials. UHSC mixture proportions were developed using local materials so that UHSC may be made more affordable to a wider variety of applications. Specifically, local sand with a top size of 600 um, and locally available Type I/II cement and silica fume were used in this research. Each of these material selections is seen as an improvement in sustainability for UHSC. Two mixtures (one with and one without fibers) were recommended as the UHSC mixtures. The greatest compressive strengths obtained in this study were 165.6 MPa for UHSC with steel fibers and 161.9 MPa for UHSC without fibers. The compressive and flexural strengths obtained from the UHSC mixtures developed in this work are comparable to UHSC strengths presented in the literature. Producing this innovative material with local materials reduces the cost of the material, improves sustainability, and produces mechanical performance similar to prepackaged, commercially available products. 展开更多
关键词 Compressive strength local materials modulus of rupture SUSTAINABILITY ultra-high strength
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Hybrid reliability model for fatigue reliability analysis of steel bridges 被引量:1
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作者 曹珊珊 雷俊卿 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期449-460,共12页
A kind of hybrid reliability model is presented to solve the fatigue reliability problems of steel bridges. The cumulative damage model is one kind of the models used in fatigue reliability analysis. The parameter cha... A kind of hybrid reliability model is presented to solve the fatigue reliability problems of steel bridges. The cumulative damage model is one kind of the models used in fatigue reliability analysis. The parameter characteristics of the model can be described as probabilistic and interval. The two-stage hybrid reliability model is given with a theoretical foundation and a solving algorithm to solve the hybrid reliability problems. The theoretical foundation is established by the consistency relationships of interval reliability model and probability reliability model with normally distributed variables in theory. The solving process is combined with the definition of interval reliability index and the probabilistic algorithm. With the consideration of the parameter characteristics of the S-N curve, the cumulative damage model with hybrid variables is given based on the standards from different countries. Lastly, a case of steel structure in the Neville Island Bridge is analyzed to verify the applicability of the hybrid reliability model in fatigue reliability analysis based on the AASHTO. 展开更多
关键词 hybrid reliability model (HRM) consistency relationships linear and bilinear S-N curve fatigue reliability normal distribution
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Novel hybrid FRP tubular columns for sustainable mining infrastructure:Recent research at University of Wollongong 被引量:1
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作者 Yu Tao Remennikov Alex M. 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期311-316,共6页
This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer(FRP) tube and an annular concrete infill betwee... This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer(FRP) tube and an annular concrete infill between them. The two tubes may be concentrically placed to produce a section form more suitable for columns, or eccentrically placed to produce a section form more suitable for beams. The FRP is combined with steel and concrete in these hybrid structural members in such a way that the advantages of FRP are appropriately exploited while its disadvantages are minimized. As a result, these hybrid members possess excellent corrosion resistance as well as excellent ductility and seismic resistance. This paper summarizes existing research on this new form of structural members, and discusses their potential applications in mining infrastructure before presenting a summary of the recent and current studies at University of Wollongong(UOW) on their structural behaviour and design. 展开更多
关键词 Hybrid column Tubular column Fibre reinforced polymer Sustainable mining infrastructure
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Generation of 3D random meso-structure of soil-rock mixture and its meso-structural mechanics based on numerical tests 被引量:2
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作者 徐文杰 张海洋 +1 位作者 介玉新 于玉贞 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期619-630,共12页
The mesoscopic failure mechanism and the macro-mechanical characteristics of soil-rock mixture(S-RM) under external load are largely controlled by S-RM's meso-structural features. The objective of this work is to ... The mesoscopic failure mechanism and the macro-mechanical characteristics of soil-rock mixture(S-RM) under external load are largely controlled by S-RM's meso-structural features. The objective of this work is to improve the three-dimensional technology for the generation of the random meso-structural models of S-RM, for randomly generating irregular rock blocks in S-RM with different shapes, sizes, and distributions according to the characteristics of the rock blocks' size distribution. Based on the new improved technology, a software system named as R-SRM3 D for generation and visualization of S-RM is developed. Using R-SRM3 D, a three-dimensional meso-structural model of S-RM is generated and used to study the meso-mechanical behavior through a series of true-triaxial numerical tests. From the numerical tests, the following conclusions are obtained. The meso-stress field of S-RM is influenced by the distribution of the internal rock blocks, and the macro-mechanical characteristics of S-RM are anisotropic in 3D; the intermediate principal stress and the soil-rock interface properties have significant influence on the macro strength of S-RM. 展开更多
关键词 soil-rock mixture(S-RM) three dimensional meso-structure meso-structural mechanics(M-SM) true-triaxial numerical test random simulation
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Experimental Study on Aqueous Phase Entrainment in a Mixer-settler with Double Stirring Mode 被引量:6
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作者 Wang Shuchan Zhang Tingan +2 位作者 Zhao Qiuyue Liu Yan Wu Qiuyang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第2期59-62,共4页
The mixer-settler is a core device of solvent extraction for separating rare earth elements. There are some adverse effects like high rare earth accumulation and poor production efficiency during industrial production... The mixer-settler is a core device of solvent extraction for separating rare earth elements. There are some adverse effects like high rare earth accumulation and poor production efficiency during industrial production. Current researches usually focus on changing the structure of the mixer-settler without making a breakthrough towards gravity clarification. In this paper, in order to improve the efficiency of clarification, a mixer-settler with double stirring mode was designed and manufactured by adding a stirring device in the settler after reducing the volume of the settler. The innovation of this research involves adopting the ultraviolet-visible spectrophotometer to investigate the quantity of aqueous phase entrainment at the settler outlet in order to measure the clarification degree. Experimental results show that the clarification effect with stirring is better than that without stirring. The clarification effect is ameliorated as the stirring speed increases. Generally, the clarification effect shows a best condition when the offset distance is 12.5 cm, making the phase entrainment reduced to less than 0.1%. When the clearance over the tank bottom is 7 cm and 10 cm, respectively, the quantity of aqueous phase entrainment is better than the case with a clearance of 4 cm. The results show that the stirring paddle close to the mixed phase zone can better promote the two-phase separation. 展开更多
关键词 MIXER-SETTLER aqueous phase entrainment stirring speed clearance over the tank bottom offset distance
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Reliability of flip-chip bonded RFID die using anisotropic conductive paste hybrid material 被引量:1
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作者 Jun-Sik LEE Jun-Ki KIM +2 位作者 Mok-Soon KIM Namhyun KANG Jong-Hyun LEE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期175-181,共7页
A reliability of flip-chip bonded die as a function of anisotropic conductive paste (ACP) hybrid materials, bonding conditions, and antenna pattern materials was investigated during the assembly of radio frequency ide... A reliability of flip-chip bonded die as a function of anisotropic conductive paste (ACP) hybrid materials, bonding conditions, and antenna pattern materials was investigated during the assembly of radio frequency identification(RFID) inlay. The optimization condition for flip-chip bonding was determined from the behavior of bonding strength. Under the optimized condition, the shear strength for the antenna printed with paste-type Ag ink was larger than that for Cu antenna. Furthermore, an identification distance was varied from the antenna materials. Comparing with the Ag antenna pattern, the as-bonded die on Cu antenna showed a larger distance of identification. However, the long-term reliability of inlay using the Cu antenna was decreased significantly as a function of aging time at room temperature because of the bended shape of Cu antenna formed during the flip-chip bonding process. 展开更多
关键词 RFID inlay ACP flip-chip bonding process RELIABILITY
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Formation mechanisms of water inrush and mud burst in a migmatite tunnel:a case study in China 被引量:5
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作者 WU Guo-jun CHEN Wei-zhong +2 位作者 YUAN Jing-qiang YANG Dian-sen BIAN Han-bian 《Journal of Mountain Science》 SCIE CSCD 2017年第1期188-195,共8页
This paper presents a case study of water inrush and mud burst occurring in a migmatite tunnel to study its formation mechanisms. The geological investigation and mineralogical analysis showed that water inrush and mu... This paper presents a case study of water inrush and mud burst occurring in a migmatite tunnel to study its formation mechanisms. The geological investigation and mineralogical analysis showed that water inrush and mud burst in the migmatite was closely related to the component of the host rock. High content of soluble minerals,e.g.,calcite and dolomite,would make the migmatite rock prone to be fragmentized,isintegrated and eventually form different sorts of connected or semi-connected veins. The field exploration revealed most cavities in the magmatite tunnel were eroded by groundwater and formed large interconnected networks. The two faults and the dike in the magmatite tunnel became the preferred paths and provided great convenience for plenty of precipitation and mud slurry. Due to high water pressure and blast disturbance,the cavities can soon connect each other as well as all sorts of veins,forming a complex ground channel for water inrush and mud burst. To estimate the potential occurrenceof water inrush and mud burst,the water bursting coefficient was employed. The results showed the water bursting coefficient of the magmatite tunnel was much bigger than the threshold values and it can be used to explain the accident of water inrush and mud burst occurring in the magmatite tunnel. 展开更多
关键词 Water inrush Mud burst Migmatite Formation mechanism Tunnel
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Analytical Algorithms for the Blend Ratios by Fibre-bundle Tensile Curves Part Ⅲ: The Definition Method and the Relationships between the Blend Ratio and Tensile Parameters Calculated from Different Ways
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作者 于伟东 Ron Postle 严灏景 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期1-7,共7页
The algorithms of the strength, work, modulus and percentage methods have been introduced and discussed in Part Ⅰ and Part Ⅱ of the series papers. As the following, the percentage-function calculation and the freque... The algorithms of the strength, work, modulus and percentage methods have been introduced and discussed in Part Ⅰ and Part Ⅱ of the series papers. As the following, the percentage-function calculation and the frequency-function calculation of the definition method are defined and developed in detail. Meanwhile, the procedures to find the tensile parameters are analysed experimentally and involve “ED” being the average values of the corresponding tensile parameters of each bundle tensile curve measured; “EC” being the tensile parameters obtained from the averaged experimental tensile curve; and “TC” being the parameters of the theoretical tensile curve according to the corresponding nominal blend ratio. The theoretical and experimental results indicate that the blend ratio estimated by the definition method from wool/polyester blended fibre bundles has a high correlation with the actual blend ratio though the variables to be known in this method are the most of all the methods and there exist the difficulty to solve fibre bundle tensile behaviour without fibre broken in accuracy and that there are high correlations between the EC and TC data and the tensile parameters should be calculated using the EC method rather than the ED method with the exception of the bundle initial modulus. The relationships between blend ratios and the tensile properties of blended fibre bundles can be used to select the optimum blend ratio of blended tops or yarns. 展开更多
关键词 fibre bundle blend ratio tensile curve WOOL polyester fibre
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Edible Films of Blended Cassava Starch and Rice Flour with Sorbital and Their Mechanical Properties 被引量:1
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作者 Pomchai Rachtanapun Dararat Pankan Darin Srisawat 《Journal of Agricultural Science and Technology(A)》 2012年第2期252-258,共7页
In this study, the mechanical properties (tensile strength, elongation at break and folding resistance) of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions wi... In this study, the mechanical properties (tensile strength, elongation at break and folding resistance) of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions with sorbital used as a plasticizer. A suitable ratio of cassava starch and rice flour to water at 10% w/v was used to form a film solution. The addition of a plasticizer agent up to 30% w/w of blending compositions improved the mechanical properties of the generated films. The mechanical properties of the edible blended films with 30% plasticizer were strongly dependent on the blending compositions. Our results pointed out that the cassava starch and rice flour films at a ratio of 70:30 with sorbitol 30% (w/w) had the highest tensile strength which related to folding endurance of the films. 展开更多
关键词 BIOPOLYMER cassava starch mechanical properties rice flour sorbital.
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Dependence of Mixed Aerosol Light Scattering Extinction on Relative Humidity in Beijing and Hong Kong 被引量:4
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作者 LI Cheng-Cai HE Xiu +2 位作者 DENG Zhao-Ze Alexis Kai-Hon LAU LI Ying 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期117-121,共5页
The hygroscopic properties of mixed aerosol particles are crucial for the application of remote sensing products of aerosol optical parameters in the study of air quality and climate at multiple scales. In this study,... The hygroscopic properties of mixed aerosol particles are crucial for the application of remote sensing products of aerosol optical parameters in the study of air quality and climate at multiple scales. In this study, the authors investigated aerosol optical properties as a func tion of relative humidity (RH) for two representative me tropolises: Beijing and Hong Kong. In addition to the RH data, mass concentrations of PM10 (particulate matter up to 10 utm in diameter) and aerosol scattering extinction coefficient (aext) data were used. The relationship between the mass scattering extinction efficiency (MEE, defined as O'ext/PMl0) and RH can be expressed by regression func tions asf= 1.52x + 0.29 (re= 0.77),f= 1.42x + 1.53 (re= 0.58),f= 1.19x + 0.65 (re= 0.59), andf= 1.58x + 1.30 (re = 0.61) for spring, summer, autumn, and winter, respec tively, in Beijing. Here, f represents MEE, x represents I/(1-RH), and the coefficients of determination are pre sented in parentheses. Conversely, in Hong Kong, the corresponding functions are f= 1.98x- 1.40 (r^2= 0.55),f = 1.32x - 0.36 (r^2 = 0.26),f= 1.87x - 0.65 (r^2 = 0.64), and f= 2.39x - 1.47 (r^2 = 0.72), respectively. The MEE values for Hong Kong at high RHs (RH 〉 70%) are higher than those for Beijing, except in summer; this suggests that aerosols in Hong Kong are more hygroscopic than those in Beijing for the other three seasons, but the aerosol hy groscopicity is similarly high in summer over both cities. This study describes the effects of moisture on aerosol scattering extinction coefficients and provides a potential method of studying atmospheric visibility and ground level air quality using some of the optical remote sensing products of satellites. 展开更多
关键词 mass extinction efficiency hygroscopicityJBeijing Hong Kong /
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