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They found that the polymer molecule weight was a bit larger with a relative narrower distribution, in addition, there are researches on the fluid dynamics [6,7], materials science [8] and analytical chemistry [9] under acoustic levitation.
The wavelength range was 250~410nm; The single-axis acoustic levitation device was prepared by Laboratory of Space Materials Science, Northwestern Polytechnical University, China.
Proceedings of the Symposium on Materials Processing in the Reduced Gravity Environment of Space.
Polymerization of N-Isopropylacrylamide under magnetic levitation, Journal of Physics: Conference Series.51(2006)458-461
Compact acoustic levitation device for studies in fluid dynamics and material science in the laboratory and microgravity, Rev Sci Instrum. 56(1985) 2059-2065

In addition, you can optimize material flow, resource utilization and logistics for all levels of plant planning from global production facilities, through local plants, to specific lines. 3 Problem description Facility layout problem is a typical quadratic assignment problem.Put n facilities into n positions,each position can put only one facility,then there are n!
results at all.It is known that the amount of material handling between each two facilities is Wij,and the distance between each two positions is Dij.The problem is how to place these facilities can let the amount of material handling be minimum, namely, . 4 The analysis of examples A computer manufacturing company need 8 departments（D1, D2, D3, D4, D5, D6, D7, D8）to complete production process.There are 8 positions（A, B, C, D, E, F, G, H）in the company to place these departments.The amount of material handling between each two departments is given by the table 1,and the distance between each two positions is given by the table 2.How to place these departments can let the amount of material handling be minimum?
Table 1 The amount of material handling between each two departments D1 D2 D3 D4 D5 D6 D7 D8 D1 92 88 37 43 68 74 55 D2 40 56 55 70 58 98 D3 70 28 36 80 36 D4 64 88 82 38 D5 28 46 62 D6 26 55 D7 80 D8 Table 2 The distance between each two positions A B C D E F G H A 2 3 4 4 5 6 7 B 3 3 5 4 5 6 C 3 4 4 5 5 D 2 3 4 5 E 2 3 4 F 3 4 G 3 H 5 The modeling and simulation Use the combination of a Buffer and a SingleProc to represent one department,then the department D1 can be represent as figure 1.Use a TableFile to record department discharge order.We suppose that row 1 to row 8 represent A to H,then from figure 2 we can see D1 to D8 was placed into A to H respectively.Use a Source to generate MU which represent the material handling between each two department.So that we can establish a simulation model to calculate the total amount of material handling.
In this model,we use GASequence module and GAwizard module to solve the problem.From figure 3 and figure 4 we can see the best solution is (6,3,4,1,2,7,8,5) and the amount of material handling is 6140.
References [1] YU Jun, FAN Liuqun, MA Yumin:Research on Pulling Production Simulation Based on eM-Plant，Computer Simulation [2]Peng Wangming, Zhang Xiaochuan:Application of Em-plant in Simulation to Material Flow Operation, Journal of Wuhan University of Technology(Transportation Science &Engineering) [3]Wang Yiqiong, Mi Zhiwei:The application combined with SLP and genetic algorithm in workshop equipment layout, computer engineering and applications [4]YAO Haifeng, FENG Xunsheng, GUO Ding-jun:Simulation Study on Balancing Technology of Automobile Spare Parts Production Line Using eM -plant,Logistics Technology [5]Wei Qiyong, Xu Kelin, Jiang Bo:Research on Decision Model of Buffer Area Used by the Manufacturer of Automotive Parts,Diesel Engine

Research shows that the performance and abrasion mechanism of valve seat with different forming and surface treatment is different [4-5], therefore, the material and forming technology of valve seat is very important to it’s use effect and life.
Eutectic carbide fracture process as follows: in forging process, materials tensile deformation first, also make biggest deformation of the eutectic carbide near the flow direction under tensile stress, large eutectic carbide broken into small carbide, and was wrapped under the plastic flow and arranged along the metal flow direction, improved the continuity of matrix and enhanced toughness greatly.
Table 1 Hardness and strength of valve seat alloy states tensile strengthσb/Mpa elongation percentageδ/% hardness/HRC forging 1063.8 25.9 58.1 Strength value of forging iron had relatively substantially improve than that of the centrifugal casting [8]high chromium cast iron, this may be due to the two kinds of stress state condition is different in sample internal. there are certain stress in the centrifugal casting [8] high chromium cast iron, promoted the crackle generation, however forging iron in forging process, carbide broken, reduce the stress concentration, the fine cracks reduce, thereby improving the strength of materials.
Vol.14, (2006), p. 355 [4] S.Selvi,S.P.Sankaran and R.Srivatsavan: Journal of Materials Processing Technology.Vol. 207 (2008), p. 356 [5] K.J.Chun, J.
Lin, X.Y.Zheng: Hot Working Technology .Vol. 36 (2007), p. 46 (In Chinese) [7] X.H.Zhi, J.D.Xing, Y.M.Gao, H.G.Fu, J.Y.Peng and B.Xiao:Materials Science and Engineering: A.

., Hohe Straße 6, 01069 Dresden, Germany 2Technische Universität Dresden, Institute of Materials Science, Helmholtzstraße 7, 01069 Dresden, Germany arichter-emanuel@ipfdd.de, bspickenheuer@ipfdd.de, cgheinrich@ipfdd.de Keywords: curvilinear fibre design, variable-axial, topology optimization Abstract.
Furthermore, the material can be adapted more efficiently to given load conditions.
Different strategies based on topology and material optimization have been investigated at the IPF [1].
Using this embroidery based process fibres can be placed and fixed in arbitrary angles on an in-plane moved base material.
Journal of Reinforced Plastics and Composites, Volume 17: 774-786, 1998

Journal of Vacuum Science Technology A, v. 24 (6), p. 2113- 2116, Nov/Dez 2006. ].
Another type of procedure used for the surface treatment of ferrous and non-ferrous materials is plasma nitriding.
Experimental Details Substrate materials: The material used was AISI 4140 steel.
Influence of ion-beam bombardment on the physical properties of 100Cr6 steel, Materials Chemistry and Physics, in press, 2014. ].
Hardness and residual stresses in TiN-Ni nanocomposite coatings deposited by reactive dual ion beam sputtering, Reviews on Advanced Materials Science, v. 15, p. 111-117, 2007. ].

Microstructure and Stress Variation of Semi-solid Magnesium Alloy during Isothermal compression and Its Relationship to Thixotropy Weiwei Shan1,a , Ju Fu Jiang 1,b and Shoujing Luo 1,c 1 School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, P.R.China a Swwaiww@163.com, bjiangjufu@hit.edu.cn, cluosj@hit.edu.cn Keywords: Magnesium Alloy, Thixotropy, Microstructure, Isothermal Compression Abstract: Thixotropy is the most important characteristic of semi-solid materials, and it is decided by the variation of microstructure during action of handling.
Stress-strain curves during compression can be given directly by the experimental computer, and each of curves show a peak stress in a small strain and then decrease rapidly, which originally because of the thixotropy of semisolid materials.
As the semi-solid material has such characteristics, it can flow fluently when the solid fraction is over 60 percent, and its viscosity decreased when the force is constant [2].
Semi-solid material has an original microstructure, and when force acts on it, such original microstructure can't be changed immediately but need a little more time to form new one.
True stress-true strain curves of ZK60 magnesium alloy during isothermal compression at different conditions all have a peak stress at the initial stage and then rapidly decrease, followed by decrease slowly, meanwhile, the original microstructure is broken, including forming of liquid paths and moving of solid particles, can be considered as the thixotropy of semi-solid materials. 3.

Improve the Mode and Optimize the Content to Improve the Metalworking Practice Teaching Effect JING Qin1,a, WANG Xu-gang2,b 1 Engineering Training Center, Nanjing University of Science and Technology, China 2Energy and Power Engineering Institute, Nanjing University of Science and Technology, China 210094 Nanjing, China ajingqin_w@163.com, bxgwang@yahoo.com.cn Key words: metalworking practice, teaching mold, teaching content Abstract: On the present situation of the metalworking practice, gives some suggestions to the reform of teaching mode and optimize the content, in order to make the metalworking practice play a bigger role for students to improve practical ability, enrich their own knowledge, study subsequent courses and join in work, etc.
Under the guidance of the teacher, the students should consult information, design works, determine the scheme, design parts, draw engineering drawings, select material, choose processing methods, formulate processing, manufacture, assemble parts, etc.
Along with the rapid development of mechanical manufacturing technology, national mechanical drawing standards, processing symbols and processing equipment, etc, are updated constantly, but the textbook, drawings, material, practice content of many engineering training centers cannot keep pace with the development of technology, this is a big obstacle for students understanding new knowledge, new equipment, new technology and production practice after graduation.
For example, in the plastic injection molding teaching, the author teach more basic knowledge of plastic injection mould to mold students, more knowledge of plastic injection molding machine hydraulic system to hydraulic students, more materials knowledge of plastic or mold to materials students, etc.
Journal of Suzhou College, Jan 2007, p112-113, (2007) [4] Dai Shi-ming: Optimize Metal Working Practice Contents to Strengthen Students' Innovative Ability.

Raw material fed into the reactor is fast heated in few seconds to the high temperature (around 580℃), causing immediate decomposition of macromolecules, then yielding pyrolysis steam and solid products, which are separated in next unit.
Corn stalk (components analysis presented in Table1) is selected as the biomass material.
RYIELD is selected to control pyrolysis products rate based on proximate and ultimate analysis of the biomass material, but it couldn’t show variation of reaction grade accompanying with temperature and pressure.
It shows material is balance based on the feeding biomass’ mass flow (2000lb/hr).
Journal of Huazhong University of Science and Technology, (2005), 33(9): 71-74.

Therefore a lot of potential materials to replace CdS barrier layer had been proposed in recent years [5-8].
More atoms can be moved out from the target material under large sputtering power.
Acknowledgements This work was financially supported by the National Science Council of ROC under the contract No.
Islam , S.Ishizuka , A.Yamada, K.Sakurai, S.Niki, T.Sakurai, K.Akimoto , CIGS solar cell with MBE-grown ZnS buffer layer, Solar Energy Materials & Solar Cells, Vol. 93 (2009), p. 970
Keyes, Journal of Physics and Chemistry of Solids Vol. 66 (2005), p.1862.

Although graphite is widely used as a material for making the crucibles and it allows to grow high-quality crystals, nevertheless, it has its own specific disadvantages.
The effect of use of Ta as crucible material on quality of the grown crystals is discussed.
Vodakov , Journal of Crystal Growth 211 (2000) 347-351
Talalaev , Materials Science and Engineering B46 (1997) 340-344
Makarov , Materials Science and Engin.