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Challenges in Hydrogen Fuel Cell Vehicles Commercialization Yuan Ren, Zhidan Zhong, Zhiwen Zhang School of Mechatronics Engineering, Henan University of Science and Technology Luoyang 471003, Henan Province, China,ryemailcn@163.com Keywords: Hydrogen Fuel Cell Vehicle; Proton Exchange Membrane Fuel Cells (PEMFCs); Material for Catalyst; cost; Commercialization Abstract:Current development in fuel cells and hydrogen fuel cells vehicles are first described in the paper, and then the paper gives up-to-date review of hydrogen fuel cell vehicle technological status and hydrogen infrastructure.
Then the paper analysis barriers in hydrogen fuel cell vehicle commercialization and the cost reduction challenges especially in the material for catalyst and operational condition.
Proper understanding the basic science of fuel cells working principle at the atom level is vital important for us to do.
The second is the membrane fabrication techniques and the third is the coating and plate material of bipolar plates.
For PEMFC, research efforts focused on improving technological performance in the 1980s and 1990s, and then turned towards reducing the cost of PEMFC, particularly in terms of finding a replacement material for the platinum catalyst. 3.1 Catalyst material Long-term durability of catalysts is considered as the most critical issue to commercialize the fuel cell vehicles.

Influences of Reaction Temperature on Structure and Performances of SnO2 Nanocrystals Prepared by Microwave Hydrothermal Method Li-xiong Yina, Fei-fei Wangb,Jian-feng Huang, Dan Wang, Jia-yin Li School of Materials Science and Engineering, Shaanxi University of Science & Technology, Xi' an 710021, Shanxi, China Email: ayinlx@sust.edu.cn，bWangFeifei03@126.com * Corresponding author: Dr.
Hu: Journal of Functional Materials, Vol. 4 (2003) No.34, p.375
Yu: Materials Letters, Vol. 40 (1999)No.1, p.23
Parthibavarman: Materials Letters, Vol. 63 (2009), p.896
Cornet: Materials Science and Engineering C, Vol. 15 (2001), p.203.

China 3 College of Science, Honghe University, Mengzi, Yunnan,661199, P.
After the formation of molten-salt, the raw materials can be directly ignited and then combust themselves.
Experimental Synthetic Materials.
The raw materials after weighing were preheated at 200℃ for 5 min in muffle furnace to achieve the homogeneous raw mixed materials. and then placed in the muffle furnace roasting temperature calcination at 3 h can obtain the target product .The calcination temperature were 400℃, 500℃, 600℃, 700℃ .
[10] Wu Y P, Li Y X, Wan C R: Journal Of Function Materials Vol. 31 (2000),p .18-22 [11] Guo J M, Liu G Y, Wang R, Wang B S, He Y, Chen K X:Journal Of Function Materials Vol. 40 (2009)

Machinability for C/SiC Composite Material by Electrical Discharge Machining Yongfu Zhang1,a, Weiwei Chen2,b,*, Huanwu Cheng3,c and Yuping Zhang4,d Department of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China agyshuishangpiao@163.com, bwwchen@bit.edu.cn, cchenghuanwu@bit.edu.cn dstu_zhangyuping@126.com Keywords: C/SiC composite material; Electrical Discharge Machining; Machinability Abstract.
Therefore, it could not be better if this kind of material is applied in the high temperature structural materials and space structural materials.
So it is proper to machine hard and brittle materials.
Therefore, materials like Cu-W alloy are recommended strongly to process these hard and brittle materials.
[6] Yunzhou Zhu, Zhengren Huang, Shaoming Dong, Ming Yu, Dongliang Jiang, Pressureless preparation and properties of C/SiC composites, Journal of Inorganic Materials. 22 (2007) 685-689

Preparation of polymethyl methacrylate-NaYF4:Yb:Er composite material used for holographic display Li Liu a, Ting Gaob , Jie Zhouc , Xing Huangd Department of Polymer Science, School of Material Science and Engineering , Shanghai University, Chengzhong Road, 20, Jiading District, Shanghai, 201800, People’s Republic of China.
At present, the materials used for holographic display can be divided into two major categories of inorganic materials and polymers.
materials prepared by PMMA-NaYF4:Yb:Er composite (a) stands for the mass fraction of NaYF4:Yb:Er( the mass material.
Hologram display The response diagram of the holographic display materials prepared by PMMA/NaYF4:Yb:Er composite material was shown Fig.6.
[7] Leilei Peng, Yongyue Luo and Yi Dan:Polymer Materials Science and Engineering,Vol. 3(2006), p. 152 “In Chinese“

Ultrasonic assisted turning (UAT) is an efficient cutting technique for difficult-to-cut materials.
Computational Materials Science, 2007, 39:149-154
Journal of Materials Processing Technology, 2008, 201:43-47
Journal of Materials Processing Technology, 2006,174:29-33
Journal of Materials Processing Technology, 2009, 209(9): 4490-4495

Journal of Materials Research.
Advanced Materials Research Vol. 664 (2013) p. 625-631
Series: Natural and engineering sciences.
Materials characterization by instrumented indentation using two different approache.
Materials and Dising.

Influence of Density on the Thermal Conductivity of Fiberglass Felt Yong Yang1,a,Xueyu Cheng2,b, Zhaofeng Chen1,c,Renli Fu1,d,Zhou Chen1,e, Jinglian Qiu1,f,Dan Su1,g 1College of Material Science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R.China 2Suzhou V.I.P.New Material Co., Ltd., Hong Da Fang Yuan Group, Suzhou 215000, P.R.China *Corresponding author.E-mail:zhaofeng_chen@163.com Keywords: Thermal conductivity, Density, Fiberglass felt, Heat-transfer mechanism.
Introduction Fiberglass felt are used widely as insulations and building sections in commercial and industrial applications[1].Coefficient of thermal conductivity for the Fiberglass felt is an important index,which could evaluate the thermal insulation performance of the fiberglass felt.In general,thermal insulations are classified into the following two types of materials:isotropic materials with a uniform thermal conductivity and anisotropic materials with a nonuniform thermal conductivity[2].Fiberglass felt are the isotropic materials.The thermal conductivity of the material is defined as the amount of heat crossing a unit area of the material per unit time per unit temperature gradient[3].In porous materials heat is propagated by three processes:thermal conductance through the solid and both radiation and convection through the pores[3].
In this paper,using this heat-transfer mechanism of the porous materials explains the relationship between thermal conductivity and density of the fiberglass felt.
Generally speaking,thermal properties of a fibrous material depend on:thermal properties of each phase(fiber and air),fiber volume fraction,and fiber size, orientation and mass distribution[4].The value of the thermal conductivity of heat-insulating materials,among which are fibrous materials,is affected by their density and kind,the size and location of pores,the chemical composition and molecular structure of hard constituents,the emissivity of surfaces bounding the pores,and the kind and pressure of the gas filling the pores[5].Main aim of this paper is to describe the relationship between thermal conductivity and density.According to the aim,we study the effect of density of fiberglass felt and analysis the reason.
References [1] N.E.WIJEYSUNDERA and M.N.A.HAWLADER: Effects of condensation and liquid transport on the thermal performance of fibrous insulations, Heal Mass Transfer.Vol.35,No.l0, pp.2605-2616,1992 [2]T.Ohmura1,2, M.Tsuboi1 and T.Tomimura3:Estimation of the Mean Thermal Conductivity of Anisotropic Materials.International Journal of Thermophysics, Vol.23,No.3,May 2002(©2002) [3] ARTHURL.LOEB: Thermal Conductivity: VIII, A Theory of Thermal Conductivity of Porous Materials, Journal of the American Ceramic Society-Loeb, Vol.37, No.2.p.96 [4] Moran Wang, Jihuan He, Jianyong Yu, Ning Pan: Lattice Boltzmann modeling of the effective thermal conductivity for fibrous materials, International Journal of Thermal Sciences 46(2007)848–855 [5] M.G.Kaganer, Heat Insulation in Low-Temperature Technology [in Russian], Mashinostroenie, Moscow(1966)

Nondestructive Evaluation in Materials Using Time-Frequency Analysis Methods Ki Woo Nam 1,a, Seok Hwan Ahn 1,b and Jin Wook Kim 2,c 1 Pukyong National University, Busan, Korea 2 Korea Institute of Machinery and Materials, Changwon, Korea a namkw@pknu.ac.kr, bshahn@mail1.pknu.ac.kr, Cjwkim@kmail.kimm.re.kr Keywords: Degraded Material, Velocity, Attenuation, NDE, Joint-Time Frequency Analysis Abstract.
WVD was found to be more effective for analyzing the attenuation and frequency characteristics of degraded materials through ultrasonic.
These materials are used in nuclear power plants pipes and reactors.
Nam: Journal of Testing and Evaluation Vol. 31 (2003), p. 347 [9] K.W.
Moon: J. of Applied Polymer Science Vol. 88 Issue 7 (2003), p. 1659

Experimental Materials.
Chemistry of Materials. 20(22) (2008) 7157-7163
International Journal of Cosmetic Science. 6(5) (2010) 249-260
International Journal of Food Science & Technology. 23(1) (2010) 57-63
Journal of Colloid and Interface Science. 415 (2014) 18-25.