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Production of helical polymer microfibers by electrospinning Cheng-Chun Tanga, Yun-Ze Longb* and Jun-Chi Chenc,* College of Physics Science, Qingdao University, Qingdao, 266071, China a tang.chengchun@163.com, b yunze.long@163.com, c,* chen-physics@163.com Key words: electrospinning; helical microfibers; tip collector; buckling.
By now, a great many dissolved or melt materials have been electrospun into nanofibers that may be used in fields such as sensors, optoelectronics, catalysis, textiles, filters, tissue engineering, drug delivery, and wound healing [1,3].
All the materials were weighed by a precise electronic balance (Hang Pin, FA1004N).
Acknowledgement This work was financially supported by the Program for New Century Excellent Talents in University of China (Grand No.: NCET-07-0472) and the National Natural Science Foundation of China (Grant Nos.: 11074138 and 10910101081).
Chang: Polymer Journal Vol. 41 (2009), p. 252 [10] M.K.

For spring grassland vegetation coverage rate is lowly, wind speed is large, characteristics of sand is belong to rich material, which should we to retain sand material through the appropriate protective measures to reduce wind erosion.
Results 2.1 wind conditions Data from husbandry institute section water conservation science experiment base UGT monitoring system for automatic meteorological station 2 m high 30 min average wind speed and direction of observation records (2011-2013), according to the statistics in each of the 16 direction in every wind speed frequency (table 1, in 2013, for example).
Acknowledgements This work was financially supported by the china institute of water resources and hydropower research Science Foundation (MK2013J03) and the ministry of water resources "948" project - soil erosion element migration analysis technology (201402).
[2] Rui-qiang ZHANG, Tian-ming GAO,Tie-jun LIU. pratacultural science,2010,3,27(3):21-25.
[5]Bullard J E..Journal of sedimentology Research,1997,67:499-501

Introduction Composite fabrication by using waste materials has gained much attention in recent years.
Waste materials originating from natural fibres such as sago, sisal, short silk fibre, oil palm empty fruit bunch, rice husk ash, jute fibre, rubber wood powder, jute, hemp, sisal, cotton stalk, kenaf, sugarcane banana fibers and other cellulosic fibres are used widely as reinforcement materials in various waste polymeric materials[1-2].
Polypropylene based materials are known to attract attention due to their good ability in balancing properties when mixed with soft rubbery materials [9].
Materials and preparation of composite The materials used in this study were PP homopolymer, NBR recycled product from mechanically ground used surgical gloves and RHP were grounded to 130-300 µm prior to usage.
[13] Santiagoo, R., Ismail, H., Hussin, K.The Effect of Polypropylene Maleic Anhydride (PPMAH) on Properties of Polypropylene (PP)/Recycled Acrylonitrile Butadiene Rubber (NBR r)/Rice Husk Powder (RHP) CompositesPertanika Journal of Science and Technology, 2010: 18 (2), 427-432

Table 2 Mechanical Property of Seal Ring Materials Seal materials Density [] Modulus of elasticity [] Heat expansion coefficient a [] Tensile strength [] Heat conductivity [] Temperature limit [] tungsten carbide (cobalt-based) 15 600 4 1400 100 400 hard carbon graphite 1.8 25 5 50 10 300 The structure of seal ring and load condition is of axial symmetry.
When spring specific pressure increases, the highest temperature value of static ring exceeds the material temperature limit, and the zone exceeding the material temperature limit is bigger and bigger.
Therefore, some improvement measures are put forward regarding the surface materials sealing structure and environment temperature for corrugated pipe and seal. 3.1 Improvement of seal face material As for the static ring material, some high temperature limit sealing material is recommend such as fine graphite and silicon carbide materials to improve its performance and ensure the long-term good operation of machine seals. 3.2 Improvement of the environment temperature A cooling system can be designed in the ring inside to reduce the temperature of the friction surface.
Journal of Liaoning Engineering Technology University (Natural Science), 2008 (27): 239-240 [3] Chen Kuangmin, Dong Zongyu, Chen Wenmei etc.
Chengdu: Chengdu University of Science and Technology Press, 1990 [4] Xiong Jia, Lei Yuyong, Yang Zhifeng etc.

0.25 0.25 0.26 0.26 0.23 0.25 Transport, Storage,Postal and Telecommunication Services 0.72 0.58 0.53 0.51 0.44 0.46 Commerce,Catering Services, Material Supply and Marketing 0.20 0.20 0.21 0.21 0.17 0.15 Other Services 0.17 0.18 0.18 0.17 0.18 0.17 Mean 1.17 1.15 1.11 1.04 0.98 0.93 Analysis on influence factors of change of industrial carbon emissions The total industrial carbon emissions are mostly affected by value-added industries and carbon emissions per unit added value in different industries.
Acknowledgements The paper was partly supported by National Social Science Foundation of China in 2011(11BJY020).
Science & Technology and Economy, 2012,25(1):101-105
An Empirical Study on the Relationship of Industry Structure Upgrade and Carbon Emissions in China[J].Journal of Hubei University of Economics,2010,8(5):77-81
Chemical Engineering Science, 2010,65(23):6155–6168

Semiconductor devices made of silicon, germanium, gallium arsenide and other materials, can be used as amplifier, rectifier, oscillator.
In this paper, a certain type of semiconductor FET with a massive accurate test data developed and produced by the 13th Research Institute of China Electronics Technology Group Corporation are used to research the distribution of device parameters, given its normal distribution of irrationality. 1 GaAs metal - semiconductor field effect transistor structure In order to make the results of data analysis are representative, the paper selected Metal Semiconductor Field Effect Transistor, a GaAs material, which is widely used in semiconductor devices as an object of study.
Journal of Jiangxi University of Science and Technology, 2008, 29(4): 5-8
Nonparametric Statistics with Applications to Science and Engineering[M].
Computer Science and Automation Engineering, Valdosta, USA, 2011: 542-545

Materials and methods (1) The pesticides and reagents Pesticides: 100 mg • L-1 beta cypermethrin standard, provided by the Ministry of agriculture in Tianjin Environmental protection.
(3)Material Experiment of vegetable: Lettuce, tomato, celery.
China Agricultural Science Bulletin, 2009,25 (15): 5154 [2] Wang Ping, Wang Qi, Liu Qing, etc..
Analysis of 5 pyrethroid pesticide residues in Ganoderma lucidum, poria[J].Chinese clinical laboratory science, 2007,13 (1): 57 [3] Shi Yajun, Wei Zhaojun, Jia Linfang, etc..Determination of 5 kinds of Pear by high performance liquid chromatography of pyrethroid pesticide multi residues[J].Journal of Beijing University of Agriculture, 2008, 23 (4): 2528 [4] Wei Zhaojun, Shi Y.J, Zhao J.Z, etc..Improvement for analyzing pyrethroids in vegetables by HPLC[J].Chinese Agricultural Science Bulletin, 2009,25 (7): 89.3 [5] Wang Xiang, Song Guoxin, Hu Yaoming.Method for extracting pyrethroid pesticide residues in tea GC/MS study[J].MS Sinica, 2008,29 (2): 97-100 [6] Wu Shengfang, Wang Liping, Liu Yangmang.Accelerated solvent extraction and gas chromatography tandem mass spectrometric determination of 3 pyrethroid pesticide residues in Chrysanthemum[J].Analysis of the test chamber, 2008, 27 (11): 65-67.

Lignin Structure Changes in Different Bleaching Processes Qiang Zhao 1,2, Dezhi Sun *2, Junwen Pu 1, Xiaojuan Jin 1, Mian Xing 1 1.College of material Science and Technology,Beijing Forestry University.China 2.College of environmental Science and Engineering,Beijing Forestry University.China renyann@126.com，*:Corresponding author Keywords: Populus nigra L,Lignin structure, FTIR Abstract: To study the bleaching mechanisms of H2O2 bleaching, H2O2 displacement bleaching and H2O2 /TAED bleaching, three kinds of lignin bleached with above processes were obtained.
Therefore, taking the residual lignin as original material to study the chromophore groups reaction have more practical significance.
Experimental Material The CTMP sample of Nigra poplar was provided by Shandong HuaTai Paper Corp.
Liu Shiji.Chemical kinetics of alkaline peroxide brightening of mechanical pulps[J].Chemical Engineering Science,2003,58:2229. 2.
Anna Wuorimaa,Reija Jokela.Recent developments in the stabilization of hydrogen peroxide bleaching of pulps:An overview[J].Nordic Pulp and Paper Research Journal,2006,21(4):435 4.

The in-plane traveling wave is used to design noncontact USMs [2-4] initially, of which the rotor is driven by air or fluid between stator and rotor without material wear, lead to a high rotating speed with low torque.
Acknowledgements This project is supported by the National Natural Science Foundation of China (No.10874090), NSFC-Guangdong Joint Fund (No.U0934004), and the National Basic Research Program of China (973 Program) (No.2011CB707602).
Zhao: Ultrasonic Motors Technologies and Applications (Science Press, China 2007) [2] J.H.
Zhao: Journal of Wuhan University of Technology.
Materials Science Edition 23 (2008), p. 961-963 [7] Y.X.

Experimental materials and methods Experimental materials and equipments Experimental materials: hydrogen peroxide (industrial product, Guangzhou Jinzhujiang Chemical Co., Ltd.) with the content of 30%; ferrous sulfate heptahydrate (analytical pure, Guangzhou Chemical Reagent Factory) with the content greater than 99%, mixed with distilled water to form a 5% solution for use; magnetic powder (chemical pure, Shanghai Shanhai Gongxuetuan No. 2 Experiment Factory) with the Fe3O4 content greater than 98%, and the particle size mainly between 2 and 10μm, of which 90% between 0 and 11μm; polyacrylamide (France SNF Company) with the average molecular weight between 15 and 20 million, mixed with distilled water to form a 2% solution for use; sodium hydroxide (analytical pure, Tianjin Fulu Chemical Reagent Factory) with the content greater than 96%, mixed with distilled water to form a 5% solution for use; sulfate (analytical pure, Shantou Guanghua Chemical Factory) with the content between 95%
Environmental Sciences, SEPA), JB90-D-type powerful electric mixer (Shanghai Specimen Model Factory), TG328A analytical balance (Shanghai Precision & Scientific Balance Instrument Factory), 202-AQ-type desktop dry box (Shanghai Hunan Scientific Instrument Factory) and a set of self-made high-gradient magnetic separator(Fig.1).
Fig 1 Experimental Magnetic Flocculation-high gradient magnetic separation device and operating principle Experimental materials and equipments The pollutants with magnetism are the basic elements for applying the high-gradient magnetic separation technology in wastewater treatment[5].
Chemical Engineering Science, vol. 55, Jun. 2000, pp. 1101-1113
Guo,L.L and M.Y.Cai,A Study on the Packing in High Gradient Magnetic Separator, Journal of South China University of Technology(Natural Science) vol. 26, Oct. 1998, pp. 34-39(in Chinese).