bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of LiFePO4 Synthesized by Sol-Gel Processing
Authors: Lu Jun Biao , Zhang Zhong Tai , Tang Zi Long , Shen Wan Ci
Published: March 2009

LiFePO4 powder was obtained by sol-gel processing and was characterized by SEM, XRD, TEM, and surface area measurement of Quantachrome NOVA Automated Gas Sorption system. The cathode performance was evaluated using cylindrical battery. Cycle at C/10, samples sintered at 850°C with specific surface area of 188.5M2/g deliver capacity of 157.5mAh/g and cycle dozens of times without
obvious capacity fade.
Multilayer ZrO2 Precursor Coated Polystyrene Particles
Authors: Jia Yu , Hotta Yuji , Sato Kimiyasu , Watari Koji , Bergström Lennart
Published: March 2009

Monodispersed ZrO2 (includes 8mol % Y2O3) precursor nanoparticles, which were well dispersed in aqueous solution, were successfully synthesized. The as-synthesized ZrO2 precursor nanoparticles were homogenously coated on the surface of polystyrene particles. Multilayer coating process was successfully implemented by using polyacrylic acid (PAA) to modify the surface charges
of the coated particles, which was characterized by zeta-potential, particles size distribution and scanning electron microscopy (SEM).
New Style Thin Film Cathode Materials of Rare Earth Oxide Sintered by Spark Plasma Sintering (SPS)
Authors: Li H.Y. , Wang Jinshu , Zhou Mei Ling , Bai Xin De
Published: March 2009

The molybdenum powder doped with rare earth oxide was processed by powder metallurgy method and a new style thin film cathode material was firstly processed by Spark Plasma Sintering (SPS) method in this paper. The secondary emission property of such kind of cathode materials were studied, the maxim secondary emission coefficient after the material was activated at 1600°C reached to 3.84 about
double that of traditional cathode materials application in magneto. The microstructure, element analysis and phase constitution of materials before and after the secondary emission property was measured were studied through SEM, EDAX and XRD. The results show that a rare earth layer about 5um thickness was
created after the material was activated at 1600°C. The material grain size is about 1 um or even smaller and the distribution of elements in such materials is even.
The Stability of Porous Alumina Template in Electrolyte and the Formation of Amorphous Alumina Nanowires
Authors: Zong Rui Long , Zhou Ji , Li Long Tu
Published: March 2009

The stability of porous alumina template has been investigated when the template acts as
cathode and reacts in different pH electrolytes. The cathodic reaction can be separated into four stages. In particular, there exists an autocatalyse reaction, which causes the erosion of the porous template for the local high pH solution. Hence, the template is relatively stable in lower pH electrolyte. After electrochemical reaction, long and radial distributed nanowires are got at the surface of cathode for
the etching of the fluid high pH solution.
Combustion Synthesis of Nanosized Y2Hf2O7 and Lu2Hf2O7 Powders
Authors: Liao Yi Kun , Jiang Dan Yu , Ji Ya Ming , Shi Jian Lin
Published: March 2009

Y2Hf2O7 and Lu2Hf2O7 precursor powders are prepared by nitrate solution combustion method with various fuels at 450°C, respectively. Phase evolution of the synthesized powders was determined by X-ray diffraction (XRD) techniques. Single-phase cubic Y2Hf2O7 and Lu2Hf2O7 crystalline powders were obtained by calcining the resultant combustion ash at 800°C for 2h. By controlling the pH of the nitrate solution, the type of fuel and the ratio of fuel/nitrate, nanosized powders can be obtained. The crystallite size of resultant powders is much related to the combustion flame temperature, which can be controlled by controlling the type of fuel and adjusting the fuel-to-oxidizer ratio. The influence of the ratio of reactants and the type of fuel on the properties of the final products was investigated. The crystal size and morphology were analyzed by TEM.
Surface Treatment of the Lithium Boron Oxide Coated LiMn2O4 Cathode Material in Li-Ion Battery
Authors: Chan Hong Wei , Duh Jenq Gong , Sheen Shyang Roeng
Published: March 2009

Surface modification on the electrode has a vital impact on lithium-ion batteries, and it is essential to probe the mechanism of the modified film on the surface of the electrode. In this study, a Li2O-2B2O3 film was coated on the surface of the cathode material by solution method. The cathode powders derived from co-precipitation method were calcined with various weight percent of the surface
modified glass to form fine powder of single spinel phase with different particle size, size distribution and morphology. The thermogravimetry/differential thermal analysis was used to evaluate the appropriate heat treatment temperature. The structure was confirmed by the X-ray diffractometer along with the composition measured by the electron probe microanalyzer. From the field emission scanning electron
microscope image and Laser Scattering measurements, the average particle size was in the range of 7-8µm. The electrochemical behavior of the cathode powder was examined by using two-electrode test cells consisted of a cathode, metallic lithium anode, and an electrolyte of 1M LiPF6. Cyclic charge/discharge testing of the coin cells, fabricated by both coated and un-coated cathode material, provided high discharge capacity. Furthermore, the coated cathode powder showed better cyclability than the un-coated one after the cyclic test. The introduction of the glass-coated cathode material revealed high discharge capacity and appreciably decreased the decay rate after cyclic test.
Synthesis of (1-x) Ca0.4Sm0.4TiO3 – xLi0.5Nd0.5TiO3 Ceramic Powders via Citric Acid Precursor
Authors: Zhou Dong Xiang , Huang Guo Hua , Zheng Zhi Ping , Xu Jian Mei , Gong Shu Ping
Published: March 2009

Using citric acid (CA) as a chelating agent, (1-x)Ca0.4Sm0.4TiO3 –xLi0.5Nd0.5TiO3 (CSLNT) (x = 0.3) ceramic powders were synthesized by the Pechini method. The CSLNT precursor and derived oxide powders were characterized by differential thermal analysis, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy. Only perovskite CSLNT (x=0.3) phase appeared when the CSLNT precursor was calcined at 1050°C for 3 h. Compared with the conventional solid-state reaction method, microwave dielectric ceramics with better properties could be prepared by the Pechini method at lower sintering temperature.
Synthesis of Well-Crystallized Manganese Oxide from Precipitation: Effect of Introducing Carbonate Anions
Authors: Fang Ting , Duh Jenq Gong
Published: March 2009

Powdery hausmannite (Mn3O4) is of interest in many industrial and technological
applications. It is widely used as reactive catalysts, raw material of humidity sensors, and the cathode oxides of Li-ion secondary batteries. In this study, sub-micron and nano-meter sized Mn3O4 powders are prepared by an efficient method at room temperature. Mn(OH)2 nanocrystalsare commonly precipitated at first and then oxidized in the alkaline solution containing excess OH- anions. However,
conventionally prepared Mn3O4 powders by the above process are ill-crystallized. To enhance the crystallinity of fabricated powders, CO3 2- anions are introduced into the process. The modified autoxidation method is practical to fabricate low-cost and high grade powders of Mn3O4. Advantages of the modified method are confirmed by both the electron micrographs and XRD patterns of synthesized powders. It is revealed that particle size of the products is in the sub-micron meter range, and the particle morphology can be adjusted by altering the precipitation sequence.
Thermal Explosive Deforming Synthesis of SnO2 Nano-Fiber
Authors: Li Jun Shou , Yin Yu Jun , Yan Jun , Xu Bao Cai
Published: March 2009

A new method, named the thermal explosive deforming synthesis (TEDS), for producing SnO2 nano-fibers is reported. The optimal condition for forming SnO2 nano-fibers is also discussed. The resulting SnO2 fibers have diameters in the range of 20 ~ 100 nm and are expected as the matrix materials for gas sensor, humidity sensor and piezoresistive pick-up.
Technology and Equipment on Collide Injection Moulding of Ceramics
Authors: Yang Jin Long , Dai Chun Lei , Su Liang , Huang Yong
Published: March 2009

Colloidal injection moulding of ceramics (CIMC) is a new ceramic forming technique that combines the advantages of gelcasting and injection moulding. It can inject nonplastic slurry into the mould and solidification course of ceramics slurry can be controlled by both temperature and pressure. Quick mixing technique ensures that ceramic slurry will not be solidified before casting. The
equipment of CIMC was designed and developed. High performance ceramic components with complex shape have been manufactured by this equipment.
Gelcasting of BaO-Nd2O3-TiO2 Microwave Ceramics
Authors: Fang C. , Wang Yan Xiang , Su Z.G. , Xiong Zhao Xian
Published: March 2009

Gelcasting is a novel ceramic forming process for fabricating products of complex-shaped ceramics. In this contribution, the gelcasting process is applied to manufacture green body of microwave ceramic components for resonators, oscillators and antennas. Calcined powders, dispersant and organic monomers are mixed together by ball-milling to acquire high solid loading slurry with low
viscosity. After addition of initiator and catalyst, the slurry is cast into a non-pours mold and then polymerized. The slurry is thus solidified in situ and the green bodies with the desired shapes are obtained. The dried body is rather strong and can be machined so as to get more precise or complex-shaped components. Then the green bodies are sintered at high temperature. The microwave properties (εr, Q, τf) and microstructures of the ceramics prepared by gelcasting are compared with
those of die-pressed ones.
Solid Oxide Fuel Cell PEN Structures Fabricated by Tape Casting and Co-Firing Technologies
Authors: Zhou He Ping , Liu Zhi Hui
Published: March 2009

Solid oxide fuel cell positive-electrolyte-negative (SOFC PEN) structures were fabricated by complex tape casting and co-firing technologies. La0.8Sr0.2FeO3 (LSF20) powders for cathode and 8 mol% yttria-stabilized zirconia (YSZ) powders for electrolyte were synthesized through glycine-nitrate process
(GNP). The slurries for cathode, electrolyte and anode (NiO-YSZ) were cast in sequence to form green PEN structures. Co-fired at 1200oC for 6 h, there were no delamination, crack or curl occurred in PEN structures. SEM analysis showed that YSZ electrolyte film had been sintered to full dense and the interface combinations were compact. No evident reaction product between YSZ and LSF20 was detected by XRD.
Study on Spark Plasma Sintering of NiAl2O4-Metal Inert Anodes
Authors: Sun Tao , Ning Xiao Shan , Han Yong Sheng , Zhou He Ping
Published: March 2009

NiAl2O4-metal composite material is an effective candidate for anodes used in industrial production of aluminium as a substitute for graphite anodes. NiAl2O4-Cu-Ni anode was prepared by spark plasma sintering in present paper. According to the density and electrical conductivity of the anodes, the optimal process parameters were given and the result showed that sintering temperature had the most significant influence on the properties of the inert anodes. Moreover, NiO was added to the inert anodes. The results showed that adding NiO will highly increase electrical conductivity of the inert anodes. SEM and optical microscope were applied to study the mechanism of the effect of NiO on the inert anodes.
Synthesis and Densification of Nanometer K0.6Sr0.7Zr4P6O24 Powder
Authors: Li Li , Guo Xing Zhong , Hu Xiao Zhen , Ge Man Zhen
Published: March 2009

Nanometer K0.6Sr0.7Zr4P6O24 (KSZP) powders were synthesized from KNO3, Sr(NO3)2, NH4H2PO4 and ZrOCl2·8H2O by a direct co-precipitation method. The as-prepared precipitates and KSZP powders were characterized by thermal analysis, X-ray powder diffraction, granulometer and scanning electron microscope. The crystallization and particle characteristics of the KSZP powder product depend on treatment temperatures and the nanometer KSZP powder can be attained after
heat-treated at 900°C. The effects of the sintering conditions on the densification of nanometer KSZP powder and the properties of KSZP ceramics were studied. Under the sintering temperature of 1380°C and the sintering time of 2h and the additive of Nb2O5 2wt%, the KSZP ceramic from the nanometer powder after heat-treated at 900°C has better comprehensive properties.
Dielectric and Ferroelectric Properties of Ba1-xSrxTiO3 Thin Films Prepared by Pulsed Laser Deposition
Authors: Wang S.Y. , Cheng Bo Lin , Wang Can , Peng Wei , Dai S.Y. , Chen Zhao Hui
Published: March 2009

In this work, BST (x=0.7, 0.5, 0.3) films have been deposited onto Nb-SrTiO3 substrate with pulsed laser deposition. The crystal structure and surface morphology have been characterized by X-ray diffraction (XRD) and atomic force microscopy, respectively. XRD results revealed that in certain elaboration condition the films were aligned along (00l) direction, normal to the substrate
surface. The dielectric loss, relative dielectric permitivity, and polarization of BST films strongly depended on Sr content at room temperature. The tunability of relative dielectric permitivity of BST films exhibited strongly dependence on Sr content, and BST-0.5 shows the maximun K (K = tunability/loss) value.
TiO2 Coating on Optical Fiber with Different Slurry States
Authors: Liu Yi Rong , Liu Jia Chen , Tian Boran , Wei Yan Qiu , Zhao Yu Hong
Published: March 2009

In order to meet a need of application of photocatalyst, a slurry dipping method was
adopted for nano-TiO2 coating on optical fiber. Three slurry states were designed and their effects on coating quality were investigated. Experimental results showed that paste state may lead to surface cracks in coating. Both flocculent and dispersive slurry states can form high quality coatings whose coating microstructures are different, the former resulted in a loose and thicker coating and the later resulted in a dense and thinner coating, which supplied a basis for further study on effect of photocatalytic reaction and design of photocatalyst reactor.
Study on the Macro-Residual Stress of 304 Stainless Steel Coated with TiO2-SiO2 Thin Films by Sol-Gel Process
Authors: Yu Xin Gang , Zuo Yanbin , Ma Hong Wen , Zhao Hui Feng , Luo Wu Wen , Bi Wenrue , Li Wang
Published: March 2009

X-ray diffraction (XRD) method to measure the residual stress in the metal substrate surface layer and the medial oxide layer between thin film and metal substrate was introduced and the sol-gel TiO2-SiO2 thin film was successfully prepared on SUS304 stainless steel substrate by dip-coating process.
The macro residual stress existing in metal substrate was analyzed by XRD. It turns out that the compressive stress existing in the metal substrate surface layer decreases with the raising of heat-treated temperature and that the compressive stress of metal substrate surface layer and the tensile stress of the medial
oxide layer increase with the increase of the withdrawal speeds of the sol-gel dip-coating. Based on the above study, colored stainless steels of high quality were prepared by sol-gel process for the first time.
Preparation of TiO2 Coating on the Glass and Hydrophilicity under Sunlight Irradiation
Authors: Luo Zhong Kuang , Cai Hong Hua , Liu Jian Hong , Hong Wei Liang , Tang Shaojin
Published: March 2009

The precursor solution of titanium oxide coating was prepared by using titanium-oxygen sulfide. Solution with PH value of 8.5 was used to for coating on the surface of glass through dipping. The coatings were analyzed with DSC, AFM and XRD. The hydrophilic results of titanium oxide coating were obtained according the water contact angle measurement in the sunlight irradiation condition. The experimental results demonstrate that this solution is a good precursor for coating of
titanium oxide, and the coatings treated at a higher temperature have shown good hydrophilic property.
Preparation and Properties of CuInS2 Thin-Film by Successive Ionic Layer Adsorption and Reaction (SILAR) Method
Authors: Jin Zheng Guo , Shi Yong , Qiu Ji Jun , Liu Xiao Xin
Published: March 2009

CuInS2 thin films were deposited on galss substrate by successive ionic layer absorption and reaction (SILAR) method at room temperature. CuCl2, InCl3, and Na2S were used as precursor materials. The thin films were obtained during the dipping of 20-40 cycles and after annealing in the N2 atmosphere at 500°C. The characterization of the film was carried out by X-ray diffraction, scanning electron microscopy, optical absorption spectrum and X-ray photoelectron spectra. Quantification of the XPS peaks shows that the molar ratio of Cu:In:S of the film is close to the stoichiometry of CuInS2. XRD result demonstrated that the formed compound is CuInS2 with chalcopyrites crystal structure. Direct band gap was found to be 1.5eV from optical absorption spectrum.
Preparation of Y-Doped Barium Cerate and Strontium Cerate Membranes
Authors: Gu Jing Hua , He Liang
Published: March 2009

BaCe0.9Y0.1O3-a and SrCe0.9Y0.1O3-a powders were synthesized by both the solid-state reaction method and the liquid citrate method. The shrinkage, porosity and relative density of membranes prepared from these powders were determined, after sintering at 1550°C (BaCe0.9Y0.1O3-a membrane) or 1450°C (SrCe0.9Y0.1O3-a membranes) for 3 hours. The XRD patterns show that the crystal structures of the prepared powders and the sintered membranes are orthorhombic perovskite structures. The membranes prepared from the powders synthesized by the solid-state reaction method are denser than those from the powders synthesized by the citrate method with the same composition under the identical sintering conditions.
Processing and Characterization of La2O3-SiO2-B2O3 (LSB) Based Glass-Ceramics for LTCC Application
Authors: Lee Yao Hui A. , Wei Wen Cheng J.
Published: March 2009

Synthesis of La2O3-SiO2-B2O3 (LSB) based glass-ceramics using glass melting method has een investigated in this study. XRD result showed that some LSB glass systems in this study were ntirely amorphous phases. In addition, TMA results revealed that the LSB/mullite (LSBM) glassceramics ith a mass ratio of 60/40 could be densified at 850oC, which matches the requirements for theLTCC application. Moreover, dispersive behavior of the LSB glass powder with six kinds of commercial ispersants in MEK and toluene solvent had been studied. Furthermore, tape-casting process used for ow-temperature-cofired-ceramic (LTCC) chips was conducted in order to do crystal phase identification,
microstructure analysis, and dielectric property measurement.
Fabrication of Porous Zirconia Using Filter Paper Template
Authors: Deng Yu Hua , Pan Wei
Published: March 2009

In this work, porous zirconia ceramic was synthesized using filter papers as a template. Special attention is paid to whether the structural of the filter paper can be transferred to the zirconia structure. Microstructure of so synthesized porous zirconia was observed with SEM and the phase was determined by XRD. The surface area and the pore were investigated with an automatic volumetric sorption analyzer. It has been found that the morphology of the template transmit to the porous zirconia quite well.
Advanced SiC/SiC Composite Materials for Fourth Generation Gas Cooled Fast Reactors
Authors: Kohyama Akira
Published: March 2009

As one of the most important breakthrough in the field of SiC/SiC composite materials, the new process called Nano-powder Infiltration and Transient Eutectoid (NITE) Process has been developed. The outstanding total properties of the NITE SiC/SiC composites are presented. Then, the current efforts to make attractive GFR based on the NITE SiC/SiC composites and the technology R & D to make reactor components with the NITE SiC/SiC composites are provided together with our efforts on innovative reactor designs.
Environmental Characterization of Monolithic Ceramics for Gas Turbine Applications
Authors: Ferber Mattison K. , Lin Hua Tay
Published: March 2009

Over the last 30 years, a number of programs in Russia, Europe, Japan, and the United States have sought to introduce monolithic ceramic components into gas turbines with the goals of increasing efficiency and lowering emissions. High performance silicon nitride and silicon carbide ceramics typically have been leading candidates for use in these applications. Recent field tests involving silicon nitride vanes and blades have shown that these materials can experience significant recession due to the loss of the normally protective silica scale. This paper first summarizes key findings from these field tests and then describes a relatively simple method for evaluating environmental effects in a laboratory environment.
Solidifying Concentrated Si3N4 Suspensions for Gelcasting by Ultrasonic Effects
Authors: Huang Yong , Zhang Li Ming , Ma Tian , Wang Chang An , Park Hong Chae
Published: March 2009

Ultrasonic wave were used to accelerate the solidification of Si3N4 suspensions for
gelcasting. Different zones of the suspension solidified simultaneously under ultrasonic effect and structure defects in the green body caused by asynchronous solidification of the suspension could be avoided. It was found that the amount of initiator and catalyst for the polymerization of acrylamide monomers in the suspension can be reduced significantly and the flexibility of gelcasting processing
could be improved. The mechanisms of the ultrasonic effect can be explained as following: on one hand, ultrasonic can increase the temperature of the suspension homogeneously; on the other hand, ultrasonic activates monomers, initiator and catalyst, and then boosts the reaction that initiator decomposes and generates free radicals and accelerates the polymerization rate of acrylamide monomers greatly.
Enzyme-Resistant Starch for Oral Colon-Targeting Drug Delivery System
Authors: Chen Ling , Li Xiao Xi , Li Lin , Li Bing
Published: March 2009

Colon-targeting drug delivery systems (CDDSs) are employed to improve the
bioavailability of protein and peptide drugs through the oral route. So it is important to prepare the drug carriers for oral CDDS. In this study, the Enzyme-Resistant starch (RS) was studied for use as a vehicle in oral colon-targeting drug delivery. The characteristics of RS powders were investigated by X-ray diffraction, polarizing microscopy, DSC and SEM, and their film were examined by enzymatic digestion test. The results showed that RS could be a promising film-former for pharmaceutical coatings, having good stability to enzymatic digestion. Furthermore, a novel peroral formulation using RS coating and bovine serum albumin as a model drug was studied for colon-specific drug delivery in vitro. Drug release studies have shown that RS coating could delivery the drug to the colon and the release rate in simulated colonic fluids was dependent on the biodegradation of RS and its coatings. It is indicated that the RS coated tablet is a potential system for oral CDDS.
Preparation of Electrospun PLA Nanofiber Scaffold and the Evaluation In Vitro
Authors: Wen Xian Tao , Fan Hong Song , Tan Yan Fei , Cao H.D. , Li H. , Cai B. , Zhang Xing Dong
Published: March 2009

A electrospinning process to prepare soft tissue engineering scaffold was introduced in this study. This kind of scaffold was composed with ultrathin fiber and characterized with high porosity, well-interconnected pores and high surface-to-volume ratio. Biodegradable polylaticacid (PLA) was used to spin the scaffold and the scaffold was evaluated in vitro by analysis the microscopic structure, porosity, mechanical property, especially cytocompatibility. The results indicated that the electrospun PLA scaffold showed good cytocompatibility and the tensile property
of electrospun scaffold was similar to human’s soft tissue. It could be expected that the electrospun scaffold would be potential in soft tissue engineering or soft tissue repair.
The Oriented Growth of C6 Cells on Nanogrooved Surfaces
Authors: Jin Cheng Yu , Lu Qing Hua
Published: March 2009

Surface topography was believed to be a factor affecting cellular morphology, proliferation, and differentiation. In present work, we examined the facts that nanogrooved surfaces had an effect on the attachment and alignment behavior of C6 cells in detail. The nanogrooves on the surface were fabricated by Laser-induced periodic structures (LIPS) technique (Polarized laser:λ=266nm). The parallel grooves and ridges on the polystyrene were 300-350nm in period and 40-50nm in depth. In addition, we also tried to control cells growth via surface nanostructures on the patterns. And then we evaluated the attachment and alignment of C6 cells on these substrates. After 2 days of incubation, we found that C6 cells were elongated and aligned along patterns of grooves and ridges, whereas were mostly random on smooth substrates. By observing, the response of cells to nano-sized feature suggested that the formation of fibrous cellular components, especially in the filopodium and lamellipodia, were influenced by the nanogrooves. These findings would have potential applications in tissue engineering and in the design of biosensors.
Influence of Dynamic Flow Speed on Bonelike Apatite Formation in Porous Calcium Phosphate Ceramic in RSBF
Authors: Deng Chun Lin , Chen Ji Yong , Fan Hong Song , Zhang Xing Dong
Published: March 2009

A revised dynamic immersion device was designed, and the effects of flowing speed of SBF in inner pores of ceramics on the formation of apatite in the pores were investigated in this study. The results showed some crystals were overlaid on the walls of inner pores. The crystal shape changed with flow rate of RSBF. When flow rates of RSBF were 2 ml/min, some stamen-like crystals formed on the inner walls of ceramics. In the ceramics in RSBF with flow rate of 5ml/min, besides more stamen -like crystals, a thin layer of fine deposits was overlaid on the walls of inner holes and the surface of the stamen -like crystals. But when the flow rate was 8 ml/min, only a thick layer of fine deposits on the walls of inner pores could be found. Energy dispersive spectroscopy (EDS) and Fourier Transform Infrared spectroscopy (FTIR) results revealed the deposits obtained in this study are carbonate hydroxyapatite (CHA).
The Role of Surface Physical Properties on Blood Compatibility of Titanium Oxide Films Synthesized by Unbalanced Magnetron Sputtering
Authors: Leng Yong Xiang , Yang Ping , Chen Ji Yong , Xu Lan Xin , Zhao An Sha , Sun H. , Wang Jin , Huang Nan
Published: March 2009

Surface modification has shown great potential for improving the hemocompatibility of
biomedical materials and devices. In this paper we describe our work on improving blood compatibility with Ti–O thin films prepared by unbalanced DC magnetron sputtering. The structure and surface chemical and physical properties of the films were characterized by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), SEM, sheet resistance tests, and Hall effect measurements. The sheet resistance of the titanium oxide samples increased with oxygen pressure and shows a sharp increase when only TiO2 exists in the films. The band gap, carrier density and sheet resistance of the titanium oxide films synthesized at different oxygen pressure are different. These properties affect blood compatibility significantly. We suggest that the semiconducting nature of n-type Ti–O films with bandgap 3.0~3.2 eV, sheet resistance greater than 1 Ω.cm and carrier density of about 1.17 x 1016cm-2 leads to their excellent blood compatibility.
Blood Compatibility of Chitosan Immobilized on Poly(Ethylene Terephthalate) Surface Modified by Plasma and Ultraviolet Grafting
Authors: Wang Jin , Li P. , Sun H. , Yang Ping , Leng Y.X. , Chen Ji Yong , Huang Nan
Published: March 2009

We report a study involving chitosan chains immobilized on poly (ethylene
terephthalate) (PET) films by plasma and ultraviolet (UV) grafting modification. The surface structure of the modified PET is determined by means of attenuated total reflection Fourier transform infraed spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the chains of chitosan are successfully grafted on the surface of PET. Platelet adhesion evaluation in vitro is conducted to examine the blood compatibility in vitro. Scanning electron microscopy (SEM) and optical microscopy reveal that the amounts of
adhered, aggregated and morphologically changed platelets are reduced on the
chitosan-immobilized PET films. The number of platelet adhered on the modified film is
reduced by almost 48% compared to the amount of platelets on the untreated film. Our result thus shows that chitosan immobilized on the PET surface improves blood compatibility.
In Vitro and In Vivo Evaluation of Amino Acid-Functionalized Cellulose Beads for Whole Blood Hemoperfusion
Authors: Wang Yong Jian , Yu Yao Ting
Published: March 2009

Phenylalanine linked to cellulose beads was designed as an adsorbent in whole blood hemoperfusion for the therapy of rheumatoid arthritis. In whole blood perfusion tests, the adsorbent adsorbed rheumatoid factors directly from whole blood. In vitro test showed that the adsorbent had good biocompability properties. No acute systemic toxicity and dermal irritancy with extremely low skin sensitizing activity were observed. In vivo animal test with satisfactory results was perfumed with rabbits. Experimental results show that the adsorbent holds promise as a highly
effective and safe hemoadsorbent in clinical therapy for rheumatoid arthritis patients by hemoperfusion.
Osteoblast Differentiation and Apatite Formation on Gamma-Irradiated PLLA Sheets
Authors: Isama Kazuo , Tsuchiya Toshie
Published: March 2009

The effects of the γ-irradiatted PLLA on the osteoblasts and apatite formation were
investigated in vitro. The PLLA sheet was γ-ray irradiated at the dose of 10, 25 or 50 kGy. The mouse osteoblast-like MC3T3-E1 cells and normal human osteoblast NHOst cells were micromass cultured on the PLLA sheet for 2 weeks, and then the proliferation and differentiation of the cells were determined. The proliferations of MC3T3-E1 and NHOst cells hardly changed with increasing irradiation dose. However, the differentiations of MC3T3-E1 and NHOst cells increased with irradiation dose. On the other hand, the surface of the PLLA sheet after soaking in
the medium without the cells was characterized by SEM, EDX, FT-IR and XPS. The
hydroxyapatite was formed on the surface of the PLLA sheet after soaking, and the amount of hydroxyapatite increased with irradiation dose. In summary, the γ-irradiated PLLA increased the differentiation of osteoblasts and also increased apatite-forming ability even without the osteoblasts. The osteoblast differentiation was enhanced well in the apatite formation on the surface of PLLA after the γ-irradiation.
Heating NiTi Stent in Magnetic Fields and the Thermal Effect on Smooth Muscle Cells
Authors: Li Chun Jiang , Zheng Yu Feng , Zhao Lian Cheng
Published: March 2009

The feasibility of using an alternating magnetic field from induction heating furnace to
heat the NiTi stent and the influence of hyperthermic on smooth muscle cells (SMCs) have been studied in the present work. The electromagnetic field is capable of significantly heating NiTi stents and the heating temperature can be adjusted by changing the voltage and heating time of the furnace and the position of NiTi stents. The shape and living status of SMCs were influenced by the heat
treatment procedures. There were three stages of SMCs reaction to heat: (1) when the temperature below 44°C, the living status was not changed; (2) between 44°C to 50°C, the cells shrinked and were less dyed with trypan blue, which indicated that they were still alive; (3) when the temperature was above the 50°C, all the cells died. It was found that from 44°C to 50°C, the SMCs died in
apoptosis, which might allow us to heat the implanted stent to prevent restenosis.
Protection of Human Fibroblasts from Reactive Oxygen Species by Green Tea Polyphenolic Compounds
Authors: Han Dong Wook , Kim H.H. , Son Hyun Joo , Baek Hyun Sook , Lee Kwon Yong , Hyon Suong Hyu , Park Jong Chul
Published: March 2009

The potential protective roles played by green tea compounds (GTPCs) against reactive oxygen species-induced oxidative stress in cultured fetal human dermal fibroblasts (fHDFs) were investigated according to cell viability measurement methods, such as fluorescence double staining followed by flow cytometry (FCM), MTT assay and crystal violet uptake. Oxidative stress was induced in the fHDFs, either by adding 50 mM H2O2 or by the action of 40 U/L xanthine oxidase
(XO) in the presence of xanthine (250 µM). FCM analysis was the most suitable to show that both treatments produced a significant (p < 0.05) reduction in the fHDF viability, attributed to its high sensitivity. On the microscopic observations, the cell death with necrotic morphology was appreciably induced by both treatments. These oxidative stress-induced damages were significantly (p < 0.05) prevented by pre-incubating the fHDFs with 200 µg/ml GTPC for 1 h. These results suggest that GTPC can act as a biological antioxidant in a cell culture experimental model and prevent oxidative stress-induced cytotoxicity in cells.
Interfacial Fracture Toughness Measurement of Thick Ceramic Coatings by Indentation
Authors: Bartsch Marion , Mircea Iulian , Suffner Jens , Baufeld Bernd
Published: March 2009

The basic requirement for the use of a ceramic coating is sufficient adhesion to its substrate. A measure of the adhesive properties of a coating is the interfacial fracture toughness. The test method applicable for interfacial fracture toughness measurements depends on the mechanical properties of the material system and the geometry of the test piece. In this work, indentation methods have been evaluated for the estimation of the fracture toughness of ceramic thermal barrier coatings on metallic substrates. Coatings of 100 to 300 µm thickness were applied by electron beam – physical vapour deposition. The performed test types were Vickers indentation at the interface of polished cross sections of the coating system and Rockwell indentation with a brale C indenter, penetrating the coating perpendicular to the surface. Both tests generate delamination, in which the delamination crack length corresponds to the interfacial fracture toughness. Fracture surfaces and cross sections of the fractured coatings were investigated by optical and scanning electron microscope. Determined fracture toughness values are discussed with respect to the loading conditions in the test and the fracture process – i.e. interaction between indenter and coating system and the crack propagation path.
Carbon Nanotubes Prepared by CVD
Authors: Kavecký Štefan , Šajgalík Pavol
Published: March 2009

Carbon nanotubes have been prepared by CVD from acetylene-argon gaseous system in tubular flow reactor. Acetylene gas was used as the carbon source needed for carbon nanotube growth. Several types of high porosity foam-like Ni substrate were used as catalyst material at pyrolysis temperatures from 673 to 973 K. Influence of the surface morphology of the foam-like Ni substrates on the carbon nanotubes morphology and growth have been studied.
Effect of Rare Earth Oxide and Rare Earth-Alumina-Silica Glass on Mechanical Properties of Liquid Phase Sintered Alumina Ceramics
Authors: Sedláček Jaroslav , Galusek Dušan , Šajgalík Pavol
Published: March 2009

The microstructure evolution and mechanical properties of alumina doped with rare earth oxide and rare earth-aluminosilicate glass has been investigated in order to understand better the impact of rare earth addition on hardness and fracture toughness. The aims of the present work are to examine the possibly beneficial effects of selected rare earth oxide added to alumina by two different routes in enhancing mechanical properties. The specific systems considered in this work
were as follows: liquid phase sintered alumina containing RE2O3 (RE = La, Y) and RE2O3 – Al2O3 – SiO2 glassy phase up to 5 wt. %. The Vickers hardness and fracture toughness have been compared with the undoped alumina.
Mechanical Properties and Microstructure of α-SiAlON Based Cutting Tools
Authors: Salamon David , Šajgalík Pavol , Liška M.
Published: March 2009

The main object of the presented work is the development of new ceramic cutting tools on the base of a-Sialon with other complementary phases. Owing to the presence of these secondary phases a significant improvement in the mechanical properties and chemical resistance has been achieved. The newly developed cutting tools allow a higher performance in machining of iron-based products, in particular the "heavy-to-machine-parts". Finally, the microstructure, phase composition, the resulting mechanical properties, and cutting tests are compared for the set of developed materials.
Thermal Shock Resistance of Cordierite-Mullite Refractory Composites
Authors: Chlup Zdeněk , Dlouhý Ivo , Boccaccini Aldo Roberto , Boccaccini D.N. , Leonelli Cristina , Romagnoli M.
Published: March 2009

The design of composite materials leads to the development of multi-component systems where each constituent has a specific function in the material, from technological and/or application points of view. Examples of such composite systems are the cordierite-mullite refractory materials investigated in this contribution. Two different commercially available compositions were selected for evaluation of the influence of microstructure on fracture behaviour under thermal shock conditions. The materials were exposed to water-quench tests from 1250°C and subsequently the fracture toughness was evaluated using the chevron notched specimen technique. The results were compared to those obtained on as-received materials. Microstructural damage was also studied applying fractographic techniques with the aim to gain knowledge on the thermal shock damage mechanisms acting in the materials.
Study on New Ceramic Coated Metal Powders: Microstructure and Properties
Authors: Actis Grande Marco , Piticescu Roxana M. , Bogdanescu C. , Rosso Mario , Ugues Daniele
Published: March 2009

Metal/ceramic composite materials were produced with core/shell structure by traditional pressing and the influence of the compacting parameters on the material properties has been studied. Different quantities of ceramic have been introduced to coat the base stainless steel powder. The use of a new generation of coated powders gives the opportunity to achieve near net shape massive composite exhibiting a composite microstructure, with a uniform dispersion of ceramic hard particles embedded in the metal matrix. Sintering was carried out in vacuum and at temperatures typical of metal sintering process (1250 °C). Microstructures of produced samples have been investigated through the use of LOM and SEM. Hardness as well as tensile and bending tests have been performed.
Mechanical Properties of Alumina/Zirconia Functionally Graded Material Prepared by Electrophoretic Deposition
Authors: Hvizdoš Pavol , Calderón Moreno José-Maria , Očenášek Jan , Ceseracciu Luca , Anné Guy
Published: March 2009

The mechanical properties of a quasi-symmetrical planar functionally graded material
(FGM) of Al2O3 / Al2O3+20%ZrO2 / Al2O3+5%ZrO2 prepared by electrophoretic deposition and pressureless sintering has been studied. Hardness and fracture toughness were measured using indentation methods on cross sections of samples. From the difference between lengths of cracks parallel and perpendicular to layers the residual stresses (arisen due to the thermal expansion
coefficient mismatch) were calculated, their profile along the cross section has been estimated and compared with values obtained using a finite element model.
Strength and Fractography of Piezoceramic Multilayer Stacks
Authors: Supancic Peter , Wang Z. , Harrer Walter , Reichmann K. , Danzer Robert
Published: March 2009

Modern low-voltage piezoelectric actuators consist of a stack of piezoceramic layers
(PZT) with metallic electrodes in between. Due to the use of these parts in automotive applications, a big but sensitive market is opened. During application mechanical stresses are an inherent loading of these electro-mechanical converter components. Therefore some strength of the actuators is necessary to guarantee a demanded life time. Bending and tensile tests were performed on commercial components to measure the strength in axial direction. Fracture surfaces were investigated with the methods of fractography to get information about the weakest links in the microstructure.
A Comprehensive Evaluation Model for Assessments of Grinding Machining Quality
Authors: Huang Hong Zhong , Li Yong Hua , Xue L.-H.
Published: March 2009

Grinding machining quality contains machining precision and grinding surface integrality. The factors influencing grinding machining quality have fuzzy characteristics. For example, the magnitude and measure methods of grinding surface roughness have fuzzy uncertainties. The grades of the machining quality are vague, and there is no definite boundary between “good” and “bad” machining quality. Analytical Hierarchy Process (AHP) combined with the fuzzy comprehensive evaluation technique is used to evaluate the grade condition of the quality in this paper. Considering the fuzziness of the factors, a two-stage fuzzy comprehensive evaluation model is proposed to evaluate the grinding machining quality. In light of different reliable degrees of different kinds of fuzzy operator models, the weighted average method is used. The membership degrees of the evaluation factors are determined by experts’ knowledge and experiences. The factor weights are calculated via the AHP method. Certain synthetic importance of each stage evaluation is presented through weighted sum of the relative important degree. Examples of conventional external grinding machining illustrate the effectiveness of the proposed model.
Analysis of the Grinding Mechanism with Wheel Head Oscillating Type CNC Crankshaft Pin Grinder
Authors: Fujiwara T. , Tsukamoto Shinya , Miyagawa M.
Published: March 2009

In this study, the crankshaft pin grinding mechanism, which is carried out with wheel head oscillating type CNC crankshaft pin grinder, is theoretically analyzed. In order to maintain grinding process, the pin rotates and also rocks along wheel working surface, because the wheel head oscillates with journal rotation. Then, it is made clear that cylindrical plunge grinding process progresses in the pin grinding process for the first time. Therefore, grinding speed ratio, which is defined as ratio of substantial pin surface speed to wheel surface speed, is firstly formulated. Secondly, undeformed chip size generated by a grain is estimated with the grinding velocity ratio. Finally, the grinding performance is predicted with experimental equations, which obtained previous study. By this simulation, it is made clear that dimensional accuracy and also surface roughness vary on whole of the pin surface with constant journal rotation grinding method. On the contrary, deviations of both the dimensional accuracy and the surface roughness are reduced with controlled speed ratio grinding method, in which journal rotation speed is adequately controlled.
Abrasive Technology of Single-Crystal Diamond by Diamond Abrasive Wheel
Authors: Ma Y. , Lou Z.F.
Published: March 2009

Single-crystal diamond tools can be used for cutting high precise parts with high efficiency, but it is very difficult to abrade it, which is one of study purposes in this paper. This project can be done on the high precise machine tools by using a diamond abrasive wheel with super fine grain size. In this paper, the abrading mechanism is represented, an efficient abrasive method is invented, the major factors which have an important effect on abrasive efficiency and accuracy are discussed, such as abrasive wheel grain size, bonding agent, hardness, speed, pressure and feeding speed etc and some results raising abrasive efficiency and accuracy are obtained. By using the single-crystal diamond tool abraded by author, the degree of roughness of the parts can come up to Ra0.05.
Soap Mist Jet Cooling of Grinding Processes
Authors: Babic D.M. , Torrance Andrew , Murray D.B.
Published: March 2009

Grinding, like other abrasive processes, may generate high local temperatures along the arc of cut. These can cause various forms of surface damage in the most sensitive finishing phase of the manufacturing cycle. Traditional cooling methods based on large amounts of water-oil emulsions can be both ineffective and environmentally unacceptable. A new approach to this problem has been devised utilizing the high penetrative power of fast air jets combined with a water/soap mist to greatly improve convective cooling and lubrication along the arc of cut. The results obtained offer striking improvements compared to traditional liquid coolants especially if the relative simplicity of the method is considered.
Measurement of Surface Roughness and Thickness of Silicon Wafers Using an Infrared Laser
Authors: Koshimizu S.
Published: March 2009

A non-contact method of measuring the surface roughness and the thickness of polished silicon wafers using an infrared laser is proposed. The method utilizes the property that the infrared radiation is transmitted through single-crystal silicon. An optical-power meter is used to measure the intensity of an infrared laser beam that is incident to a chamfer on a cornered silicon wafer and which exits from the other side of the chamfer after repeated total reflections inside the wafer. The experimental results show that a significant correlation exists between the intensity of the transmitted infrared radiation and the surface roughness of the silicon wafers, as well as between the intensity and the thickness of the wafers. Therefore, if a calibration curve is pre-set, the surface roughness and the thickness can be estimated from the changes in the intensity of the infrared transmittance.
Optimization of the Chemical Vapor Deposition Induced Focused Ion Beam
Authors: Choi Hon Jong , Kang E.G. , Lee Seok Woo , Hong W.P.
Published: March 2009

This paper carried out some experimentation and verification of the chemical vapor deposition induced ion beam and sputtering using the SMI8800 manufactured by SEIKO. FIB-CVD is very useful tools to repair the mask or IC with sub-micrometer precision. However it need to be much studied in some fields such as FIB-CVD mechanism and the characteristics of pattern accuracy and yield of CVD according to many parameters related to ion beam, beam scanning methods and type of specimen etc. Therefore the verification on FIB-CVD characteristic such as accuracy and yield according to scanning area and scanning time is carried out in this study. And it suggests the optimization parameters, various mechanisms of the chemical vapor deposition induced ion beam and sputtering effect for simple pattern.
MQL Cutting of Inconel 718 with a Super Lattice Coating Tool
Authors: Obikawa Toshiyuki , Kamata Y.
Published: March 2009

MQL (Minimum Quantity Lubrication) technology was applied to finish-turning of a
nickel base superalloy, Inconel 718, with a PVD coated carbide tool with a super lattice coating of TiN/AlN. Cutting lubricant used for MQL was a biodegradable synthesis ester, which was supplied to the cutting point with compressed air from the both sides of flank and rake faces of the tool. At a cutting speed of 1.0 m/s and an air supply pressure of 0.4 MPa, MQL cutting showed longer tool life and better surface finish than both the dry cutting and wet cutting. When increasing the pressure of the air supply from 0.40 MPa to 0.60 MPa, however, the corner wear, the most predominant wear in all the cutting conditions in this study, increased. When the cutting speed was increased to 1.5 m/s, the tool life in MQL decreased drastically. These results suggested that when finishing Inconel 718, the special care must be taken for choosing the pressure of air supply and cutting speed. The obtained results provided a useful understanding of the complicated influence of MQL on the cutting performance of Inconel 718.