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Full-Text Articles in Engineering

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What’S The Hang Up? The Future Of Voip Regulation And Taxation In New Hampshire, Kate Winstanley Sep 2006

What’S The Hang Up? The Future Of Voip Regulation And Taxation In New Hampshire, Kate Winstanley

The University of New Hampshire Law Review

Alice in Austria wishes to call her friend Bob in Boston, using a Boston area code to avoid charges for an international call. Using VoIP, Alice may initiate her call from any location in Austria where she may find Internet access. Once Alice connects to the Internet, she can transmit her call with the aid of a VoIP service provider, such as Skype. In order to hear and communicate with Bob, Alice can rely on a microphone and a headset that she can plug into her computer. Through VoIP, not only may Alice carry on a telephone conversation, but most …


Research Of Explosion Mechanism Of Lithium-Ion Battery, Yu-Hong Chen, Zhi-Yuan Tang, Yan-Bing He, Qiang Liu Aug 2006

Research Of Explosion Mechanism Of Lithium-Ion Battery, Yu-Hong Chen, Zhi-Yuan Tang, Yan-Bing He, Qiang Liu

Journal of Electrochemistry

The heat character of Lithium-ion battery materials and explosion mechanism of Lithium-ion cells under the overcharge,short-circuit and other abuse behavior are tested by C80 calorimeter, DSC and charge-discharge instrument.SEI reactions, LixC6/electrolyte and LixC6/PVDF reactions take place at the anodes. Electrolyte and solvent reactions happen after 178℃ and Li1-xCo1/3Ni1/3Mn1/3O2 decomposes after 230℃. The batteries explode at 150℃ oven test or 1.5C, 5.5 V overcharge and do not explode at short-circuit.


Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Jun Yuan, Qing-Chun Yu, Yi-Feng Liu, Liang-Liang Ma, Yi-Hua Wu Aug 2006

Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Jun Yuan, Qing-Chun Yu, Yi-Feng Liu, Liang-Liang Ma, Yi-Hua Wu

Journal of Electrochemistry

In this paper,cyclic voltammetry has been used to study the electrochemical performance of the treated and untreated graphite,soft graphite and PAN-carbon cloth in vanadium sulfate solution.The results show that: the reversibility of reaction can be improved on the surface of treated electrode,and the current can also increase;the electrochemical performance of treated electrode is remarkably enhanced;in the process of charge/discharge,the charge current can reach up to 20 mA/cm2,and discharge current up to 15 mA/cm2;surface morphology of the treated and untreated graphite show that the treatment can change the surface structure of electrode and also add the reaction …


Immobilization Of Cytochrome C On The Surface Of Single-Wall Carbon Nanotube And Its Direct Electron Transfer And Electrocatalysis, Ya-Jing Yin, Ya-Fen Lv, Ping Wu, Pan Du, Yan-Mao Shi, Chen-Xin Cai Aug 2006

Immobilization Of Cytochrome C On The Surface Of Single-Wall Carbon Nanotube And Its Direct Electron Transfer And Electrocatalysis, Ya-Jing Yin, Ya-Fen Lv, Ping Wu, Pan Du, Yan-Mao Shi, Chen-Xin Cai

Journal of Electrochemistry

Cytochrome c(Cyto c) was immobilized on the surface of the single-wall carbon nanotube(SWNT) by using the method of adsorption.Infrared spectroscopy indicated that the Cyto c remained in its original structure and did not undergo structural change after its immobilization on the SWNT.The direct electrochemistry of cyto c,which was adsorbed on the surface of the SWNT,was studied by cyclic voltammetry.The voltammetric results demonstrated that the SWNT had promoting effects on the direct electron transfer of Cyto c and also indicated that the immobilized Cyto c retained its bioelectrocatalytic activity to the reduction of H2O2.This modified electrode might …


Investigation Of The Direct Electrochemical Reduction Of Cr2O3 Powder In Molten Cacl2 By A Metallic Cavity Electrode, Guo-Hong Qiu, Di-Hua Wang, Xian-Bo Jin, Xiao-Hong Hu, Zheng Chen Aug 2006

Investigation Of The Direct Electrochemical Reduction Of Cr2O3 Powder In Molten Cacl2 By A Metallic Cavity Electrode, Guo-Hong Qiu, Di-Hua Wang, Xian-Bo Jin, Xiao-Hong Hu, Zheng Chen

Journal of Electrochemistry

A metallic cavity electrode is used for further investigation of the electrochemical behaviour of Cr2O3 powder in molten CaCl2(Na: ~0.02% by mass,Mg: < 0.005% by mass) at 900 ℃.The Cr2O3 powder reduction mechanism was confirmed in line with EDX and SEM analysis of the potentiostatic electrolysis products.The correlations between the particle size of metallised product and the electrolysis potential,or electrolysis time were analysed.


Studies On Synthesis And Electrochemical Performance Of LiXNi1/3Mn1/3Co1/3O2 As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang Aug 2006

Studies On Synthesis And Electrochemical Performance Of LiXNi1/3Mn1/3Co1/3O2 As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang

Journal of Electrochemistry

A series of LiNi1/3Mn1/3Co1/3O2 were synthesized by a combined hydroxides coprecipitation and calcination method.Effects of synthesizing temperature of coprecipitations and the Li∶M ratios on structure and electrochemical performance of the materials were studied.The results showed that materials synthesized with coprecipitation at room temperature(~20 ~(o)C) delivered the best electrochemical performance.Another series of cathode materials LiXNi1/3Mn1/3Co1/3O2 with different Li∶M ratios were synthesized with this method.The results showed that sintering at high temperature could cause loss of LiOH,thus more LiOH should be added.It is demonstrated that Li …


Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo2, Hong-Lan Qi, Cheng-Xiao Zhang Aug 2006

Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo2, Hong-Lan Qi, Cheng-Xiao Zhang

Journal of Electrochemistry

A pre-oxidative amperometric glucose biosensor incorporated with carbon nanotube,ferrocenemonocarboxylic acid and PbO2 was designed.The interferences coming from reduced substances,such as ascoribic acid and urine acid were eliminated by PbO2.The oxidative current is linear at the potential of +0.40 V(vs.SCE) to the concentration of glucose in the range from 0.50 to 20 mmol·L-1,and the detection limit of glucose is 0.1 mol L-1.The relative standard deviation is 3.3% for seven successive assays at 5.0 mmol·L-1glucose.This biosensors have been applied to determination of the glucose in serum with satisfying results.


The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang, Feng-Ping Wang, Yong-Chun Zhu Aug 2006

The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang, Feng-Ping Wang, Yong-Chun Zhu

Journal of Electrochemistry

The self-assembled monolayers of sodium stearate surfactant on oil/water interface was investigated by CV with copper ion as probe.The self-assembling process includes four stages,and forms a stable assembly.The electrochemical oxidation of copper ion at assembled surface is a combine controlled process both surface and diffusion with regression equation as ip = 9.214-3.889 v1/2 +0.5809v,r=0.9978,compared with the oil covered bared electrode,it is a complete surface controlled.


Investigations On Electrochemical Characteristics Of Liv3O8 Electrode In Lithium Sulfate-Water-Ethanol Electrolytes, An-Bao Yuan, Wei-Xiang Song Aug 2006

Investigations On Electrochemical Characteristics Of Liv3O8 Electrode In Lithium Sulfate-Water-Ethanol Electrolytes, An-Bao Yuan, Wei-Xiang Song

Journal of Electrochemistry

The active material of LiV3O8 prepared using low-temperature pre-reaction in solution followed by intermediate-temperature calcination at 450 ℃.The product was characterized by X-ray diffraction analysis and scanning electron microscope observation.The performance of LiV3O8  electrode in neutral lithium sulfate-water-ethanol electrolytes was investigated using electrochemical methods.Galvanostatic charge/discharge results indicated that the specific capacity of LiV3O8  electrode decreases with ethanol content increasing in electrolyte.The most appropriate water/ethanol volumetric ratio is 4 ∶1 in terms of conductivity of the electrolyte and stability of the electrode.AC impedance measurements demonstrated that the ohmic resistance of the electrolyte …


The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou Aug 2006

The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou

Journal of Electrochemistry

LiFePO4 was synthesized by means of hydrothermal reaction,in which PVA acts as disperser and glucose as carbon source. The samples were characterized by X-ray diffraction, scanning electron microscopy and electrochemical measurement. SEM results show that the sample is homogeneously composed of grains with a particle size of ca.200nm. In the charge/discharge test, the products exhibited a 3.45V discharge voltage plateau and a maximum specific capacity of 140mAh/g. After 40 cycles, its capacity only declined by 2.1%. Besides these, the mechanism for the influence of the particle size and carbon coating on the electrochemical property of LiFePO4 material was …


Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni0.475Mn0.475Co0.05]O2 For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan, Yong-Mei Wang Aug 2006

Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni0.475Mn0.475Co0.05]O2 For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan, Yong-Mei Wang

Journal of Electrochemistry

Layered Li[Ni0.475Mn0.475Co0.05]O2 materials have been prepared by a solid-state pyrolysis method.Experiments of XRD,SEM,cyclic voltammetry and charge/discharge cycling were carried out.It can be learned that when calclined at 800 ℃,the sample showed the highest first discharge capacity of 178.8 mAh·g-1 at a current density of 20 mA/g in the voltage range 2.3~4.6 V


Study On The Microstructure Of Pb-Sn Alloy Obtained From Quasi-Two-Dimensional Electrodeposition, Bin Sun Aug 2006

Study On The Microstructure Of Pb-Sn Alloy Obtained From Quasi-Two-Dimensional Electrodeposition, Bin Sun

Journal of Electrochemistry

A two-layered structure of eutectic-solid sulotion is formed in the microstructure of Pb-Sn alloy obtained from quasi-two-dimensional electrodeposition.It is showed that this unique structure is caused by the variation of the current density on the growth interface.When the interface is located in the front of the whole deposits,the current density is high.So the Pb and Sn can deposit together and the eutectic texture forms.When the interface is in the rear of the whole deposits,the current density is low.At this moment the electrodeposition of Pb is the dominant reaction,and the Pb-based solid solution appears.


Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi Aug 2006

Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi

Journal of Electrochemistry

The resistance to electrochemical oxidation of multi-wall carbon nanotubes(CNT) with various diameters is investigated by applying a fixed potential of 1.2 V(RHE) for 120 h in 0.5 mol L-1 H2SO4.The oxidation current of CNTs decreases with their diameters,but CNTs between 10~20 nm in diameter(D1020) shows the lowest oxidation current.XPS analysis shows that,after oxidation,the increase in surface oxygen for D1020 is the smallest,implying that the oxidation degree for D1020 is the lowest.The conclusion can be reached that CNTs between 10~20 nm in diameter are the most resistant to electrochemical oxidation.The difference in electrochemical stability of CNTs …


Voltammetric Behavior And Its Determination Of Acetaminophen At Poly (Congo Red) Modified Electrode, Hong-Bin Luo, Ya-Feng Zhang, Wei Chen, Xin-Hua Lin, Xiao-Yan Lin Aug 2006

Voltammetric Behavior And Its Determination Of Acetaminophen At Poly (Congo Red) Modified Electrode, Hong-Bin Luo, Ya-Feng Zhang, Wei Chen, Xin-Hua Lin, Xiao-Yan Lin

Journal of Electrochemistry

Cyclic voltammetry was used to prepare poly(Congo Red) film on glassy carbon electrode and to study the electrochemical behavior of acetaminophen on poly(congo red) modified electrode.Experimental resultal shows that the poly(congo red) modified electrode exhibits excellent electrocatalytic effect on the oxidation of acetaminophen.The peak currents of linear sweep voltammogram are linear to the acetaminophen concentrations over the range of 2.0×10-7~2.0×10-6 mol·L-1.The detection limit has been estimated to be 4.0×10-8 mol·L-1.This method can be used for the determination of acetaminophenin real sample.


Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han, Ye Chen, Mi-Lin Zhang, Chang Shu, Chun-Xia Zhang, Peng-Cheng Xu Aug 2006

Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han, Ye Chen, Mi-Lin Zhang, Chang Shu, Chun-Xia Zhang, Peng-Cheng Xu

Journal of Electrochemistry

Yttrium doped Nano-NiO were synthesized by chemical precipitation method.Characterization and performance of the samples were studied by X-ray diffraction,the results showed that the doping Yttrium did not change the crystal structure of NiO,but the size of crystalline grain was reduced.The electrochemical properties of the electrode materials were measured in the three electrode system.Electrochemical properties of NiO were researched by cyclic voltammetry,constant current charge/discharge and AC impedance methods.It could be seen that the chemical doping improved the specific capacitance and the utilization of active materials.When the weight ratio of NiO with Y2O3was 1∶0.1,the composite material had the …


Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu, Guang-Fu Wang, Zheng-Hao Wang Aug 2006

Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu, Guang-Fu Wang, Zheng-Hao Wang

Journal of Electrochemistry

taC∶N films are a good materials for semiconductor electrodes.But further studies are hampered by the ohmic contact problem,which occurs between the silicon and the lead.By studying the influence of heat treatment on the film's property,it is believed that ohmic contact should be made on the silicon first,and then the film be deposited.A set of taC∶N electrodes with various nitrogen content have been prepared.CV study indicates that the cathodic limits move slowly to positive direction.while the anodic limits are unchanged with the increasing of nitrogen content.As a result,the electrochemical windows get narrow either.


Electrochemical Behavior Of Electrolytic Manganese Dioxide In Mgso4 Solution, Dan-Mei Yu, Yu-Jun Si, Chang-Guo Chen, Yu-Ping Liu, Yan Liu Aug 2006

Electrochemical Behavior Of Electrolytic Manganese Dioxide In Mgso4 Solution, Dan-Mei Yu, Yu-Jun Si, Chang-Guo Chen, Yu-Ping Liu, Yan Liu

Journal of Electrochemistry

The rechargeability and crystal structure changing of electrolytic manganese dioxide(EMD) in MgSO4 electrolyte were investigated by cyclic voltammetry,galvanostatic charge/discharge and X-ray diffraction.The results have shown that the EMD has good rechargeability;after several initial cycles,the charge and discharge became stability;after discharge,the γ-MnO2 structure of EMD was changed,the production was reversible and could be recharged to γ-MnO2 structure again which ensured the rechargeability of EMD.


The Property Study Of Libob-Pc/Dec Electrolyte, Ying-Kun Ning, Bi-Tao Yu, Fu-Shen Li, Wei-Hua Qiu Aug 2006

The Property Study Of Libob-Pc/Dec Electrolyte, Ying-Kun Ning, Bi-Tao Yu, Fu-Shen Li, Wei-Hua Qiu

Journal of Electrochemistry

The new electrolyte salt LiBOB for Li-ion battery was synthesized in laboratory,and series of electrolytes of LiBOB and PC/DEC was compounded.The conductivity of the electrolytes was compared by changing the temperature and concentration.The cycling performance of charging-discharging was also compared by the charging-discharging test,the results showed that the varying regularity of conductivities and cycling stability and capacity were not always identical,but there were a suitable electrolyte for Li/ARG cell.The A.C.impedance and CV were used to test the compatibility of the most suitable electrolyte and ARG anode.Conclusion can be drawn that the ARG anode can be protected very well by SEI …


Degradation Of P-Nitrophenol Wastewater By Liquid Phase Catalyzed In Bipolar Liquid Bed Cell, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou, Dan Wu Aug 2006

Degradation Of P-Nitrophenol Wastewater By Liquid Phase Catalyzed In Bipolar Liquid Bed Cell, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou, Dan Wu

Journal of Electrochemistry

This investigation was performed to study the degradation of p-nitrophenol(PNP) in the bipolar liquid bed cell catalyzed by liquid phase.The hydrogen peroxide produced on cathodes with the ferrous generated Fenton's reagent to produce hydroxyl radicals which are very active toward organic compounds to strengthen bipolar liquid bed cell in disposing organic compounds.The effects of cell voltage,ferrous concentration and airflow on the COD and PNP removal efficiency were also studied.When pH=3.0,cell voltage is 30V,ferrous concentration is 500×10-6 and airflow is 0.4 m3/h,higher removal efficiency of the COD and PNP are obtained.


Electrodeposition Of Nano-Sb-Zn Alloy In Acetamide-Urea-Nabr-Kbr Melt, Peng Liu, Xin-Ai Guo, Ye-Xiang Tong, Qi-Qin Yang Aug 2006

Electrodeposition Of Nano-Sb-Zn Alloy In Acetamide-Urea-Nabr-Kbr Melt, Peng Liu, Xin-Ai Guo, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

The electroreduction of Zn(II) and Sb(III) in acetamide-urea-NaBr-KBr(343 K) were studied by cyclic volatmmetry.The reduction of Zn(II) or Sb(III) to the metals is an irreversible process.The transfer coefficient of Zn(II)+2e→Zn and Sb(III) +3e→Sb were calculated to be 0.231 and 0.319,the diffusion coefficient of Zn(II) and Sb(III) in the melt were determined as 1.70*10-6 and 3.21*10-6 cm2· s-1 respectively.The Zn-Sb films with different Zn content from 29.67 at% to 97.34 at% were electrodeposited in acetamide-urea-NaBr-KBr melt at 343 K by controlling the deposition potential and the Zn(II)/Sb(III) molar ratio.The morphology of Zn-Sb film was observed by …


Influence Of Crystallinity On The Kinetics Of Li Ion Insertation And Deinsertation In Spinel Limn2O4, Rong-Hua Zeng, Dong-Sheng Lv, Wei-Shan Li Aug 2006

Influence Of Crystallinity On The Kinetics Of Li Ion Insertation And Deinsertation In Spinel Limn2O4, Rong-Hua Zeng, Dong-Sheng Lv, Wei-Shan Li

Journal of Electrochemistry

Two spinel lithium manganese oxides of different crystallinity were prepared by sol-gel process and were studied by using inducfively coupled plasma,X-ray diffraction,scaning electron micrographs,constant charging and discharging,cyclic voltammetry and electrochemical impedance spectrometry,the results show that the sample treated under 700 ℃ has higher crystallinity than the sample treated under 500 ℃,however,the sample with lower crystallinity has higher discharge capacity and better cyclic performance that due to quicker charge exchange speed and quicker diffusion speed of Li-ion.


Recycling Of The Spent Nickel-Cadmium Batteries Based On Bioleaching Process, Liang-Shu Xia, Shi-Fu Fu, Zhong-Qing Chen Aug 2006

Recycling Of The Spent Nickel-Cadmium Batteries Based On Bioleaching Process, Liang-Shu Xia, Shi-Fu Fu, Zhong-Qing Chen

Journal of Electrochemistry

Less than 1 percent of discarded dry batteries are recovered in china.it is necessary to find an economic,fast and environmentally friendly process to recycle spent dry batteries.Bioleaching is better one of the few technology applied for the recovery of the toxic metals from hazardous spent batteries.In this study,after the acidified sludge made by the inoculated and cultured indigenous sewage sludge was acted as leaching bacteria species,the influence of the different pH values,the different residence time of the sludge in bioreactor(RTB),the leaching time,whether or not adding Fe(iron powder) to the leaching liquid on the leaching rate of Ni,Cd was tested.The results …


Determination Of The Power Law Exponent For Southern Highlands Of Tanzania, H. H. Mwanyika, R. M. Kainkwa Jul 2006

Determination Of The Power Law Exponent For Southern Highlands Of Tanzania, H. H. Mwanyika, R. M. Kainkwa

Tanzania Journal of Science

The 1/7th power law is among the methods that have been used to extrapolate wind speed to the hub heights of wind turbines from the measuring levels. However, it tends to underestimate the actual long-term average wind speeds. In this paper, the power law exponent for Makambako, a site located in the southern highland zone of Tanzania, was established using wind speeds measured at heights Z1=2 m and Z2=7 m. The average power law exponent obtained at the test site was 0.47, a value that is substantially higher than the 1/7th power law exponent. It is low during the dry …


48th Rocky Mountain Conference On Analytical Chemistry Jul 2006

48th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 48th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 23-27, 2006.


Creep Behavior Of Linear Low-Density Polyethylene Films, Y B. Unigovski, A L. Bobovitch, E M. Gutman Jul 2006

Creep Behavior Of Linear Low-Density Polyethylene Films, Y B. Unigovski, A L. Bobovitch, E M. Gutman

Journal of Metals, Materials and Minerals

The Creep of biaxially-orientated linear low-density polyethylene (LLDPE) non-crosslinked and crosslinked with β-irradiation was studied as a function of the draw ratio and irradiation dose. The creep results have shown an increase in the creep strain after the polymer irradiation with a dose below 4 Megarad (MR) in comparison with a non-irradiated film. This increase corresponds to the disorientation in the amorphous phase, which takes place as a result of the film heating during irradiation. This disorientation was demonstrated by differential scanning calorimetry (DSC) and X-ray analysis.


Kinetics Of Carbonisation, Microstructure And Properties Of Al-Al4c3 System Prepared By Mechanical Alloying, M Besterci Jul 2006

Kinetics Of Carbonisation, Microstructure And Properties Of Al-Al4c3 System Prepared By Mechanical Alloying, M Besterci

Journal of Metals, Materials and Minerals

The method of mechanical alloying process is described. Carbon transformation to carbide Al4C3 is characterised within different heat treatment schedules and nine commercial carbon powders are tested. The micromechanism of carbon incorporation into the metallic powder, and the compacting of it are described. The influence of dispersed carbides on mechanical properties is evaluated together with the influence of deformation on microstructure and properties.


Drawing Quality Steel Sheet Under Tension And Bending Condition, M Mihaliková, M Buršák Jul 2006

Drawing Quality Steel Sheet Under Tension And Bending Condition, M Mihaliková, M Buršák

Journal of Metals, Materials and Minerals

The paper analyzes the influence of the loading rate in the interval from 1 to 1000 mm/min on the mechanical properties of drawing quality steel sheet with the gauge of 1 mm, used for the manufacturing of automotive parts, under tension and bending conditions. It describes the aspects of material characteristics under tension and bending conditions, while bending tests were made on notched specimens (a modified impact bending test). The paper presents knowledge that using a modified notch toughness test. It is possible to achieve the pressability (formability) characteristics corresponding to dynamic strain rates even under the static loading.


Properties Of Collagen/Chitosan Scaffolds For Skin Tissue Engineering, C Tangsadthakun, S Kanokpanont, N Sanchavanakit, T Banaprasert, S Damrongsakkul Jul 2006

Properties Of Collagen/Chitosan Scaffolds For Skin Tissue Engineering, C Tangsadthakun, S Kanokpanont, N Sanchavanakit, T Banaprasert, S Damrongsakkul

Journal of Metals, Materials and Minerals

Biopolymer blends between collagen and chitosan have the potential to produce cell scaffolds with biocompatible properties. In this study, porous scaffolds were fabricated by freeze drying the solution of collagen and chitosan and crosslinked by dehydrothermal treatment (DHT). Various types of scaffolds were prepared by varying compositions of collagen and chitosan. The scaffolds were fully characterized by Fourier transform infrared (FT-IR) spectroscopy. The results proved that collagen and chitosan scaffolds in all blending compositions contained only physical but not chemical interaction in molecular level. The compressive modulus from a universal mechanical testing machine decreased with increasing the compositions of chitosan. …


Multilayered Systems Of Nanostructured Tib2 Thin Films And Its Mechanical Properties, N Panich, P Wangyao, S Hannongbua, P Sricharoenchai, S Sun Jul 2006

Multilayered Systems Of Nanostructured Tib2 Thin Films And Its Mechanical Properties, N Panich, P Wangyao, S Hannongbua, P Sricharoenchai, S Sun

Journal of Metals, Materials and Minerals

This study focuses on the development of single and multilayer TiB2 coatings with Ti interlayer with the aim of improving the mechanical integrity of the coating-substrate system. The nanostructured TiB2 thin films and multilayered coatings were deposited on high speed steel substrates by magnetron sputtering. The resultant coating systems were evaluated with respect to microstructure, fractured cross-section and fundamental properties such as cross-sectioned fracture, surface roughness, hardness, modulus and coating adhesion to the substrate. It was found that the adhesion strength of TiB2 coating to HSS substrate could be significantly enhanced in the multilayer system, and by a proper combination …