bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxidation Damage of APS Thermal Barrier Coatings under High Temperature
Authors: Qi Hong Yu , Yang Xiao Guang , Li Rui , Wei Hong Liang
Published: March 2009

Thermal barrier coatings (TBCs) have received increased attention for advanced gas
turbine engine application. The oxidation damage plays an important role of the failure under high
temperature load. An Y2O3 partially stabilized ZrO2 ceramic top coating was deposited a NiCrAlY
bond coating by air plasma spray (APS). The substrate was directionally solidified superalloy
(DZ40M). Isothermal oxidation has been performed at 700 and 1050 for 100h. The oxidation
results in three transformations of the weight, the interface and the surface characters. All the
specimens were characterized by highly precision balance, scanning electron microscopy (SEM) in
cross-section, microscope with MFK2 visual measurement system on its surface. The curve of
oxidation kinetics is obtained by weighting those specimens. The weight gain of the specimen under
700 is close to zero. Under 1050 the weight gain is very distinct. On the other hand, the interface
cracks occur and extend at the interface between the ceramic and bond coating by SEM method. The
thermal growth oxide (TGO) gradually appears on the coating surface under high temperature
oxidation by MFK2. Last but not least, those observations will provide some ideas and damage
parameters for the non-destructive inspection (NDI) for TBC under thermal load.
Single Diamond Dressing Characteristics of CMP Polyurethane Pad
Authors: Liao Yunn Shiuan , Tsai M.Y. , Sung James C. , Pai Yang Liang
Published: March 2009

The fundamental characteristics of dressing action on the polyurethane pad are
investigated via dressing by single diamond of different orientations, dressing parameters and
dressing path in this study. Experimental results show that a groove with pile-up on both side walls
forms as the diamond moves over the pad with a specific dressing depth. The resulting asperities on
the pad are strongly affected by the diamond orientation. Plowing is found to be the major
mechanism responsible for this surface topology if dressing is conducted by the face of a diamond.
On the contrary, cutting action dominates when the point of a diamond is responsible for dressing. It
is also found that dressing velocity has an insignificant effect on the groove and ridges created on
the pad. The depth of the groove is smaller than the dressing depth due to the spring back of the pad.
When the groove created is repeatedly dressed over the same track, the ridge height and groove
depth increases for each additional dressing. When two grooves cross each other, the ridges at the
four corners of the intersection grow while the depth of the overlapped area decreases. These ridges
will become the pressure enhancer of the abrasives to polish the wafer.
Critical Cutting Condition for Brittle-Ductile Transition of KDP Crystals in Ultra-Precision Machining
Authors: Wang Jing He , Chen Ming Jun , Dong Shen , Wang H.X. , Zhang J.H. , Zong Wen Jun
Published: March 2009

In this paper, mechanical characteristics of KDP crystal anisotropy are analysed
theoretically. Vickers indentation experiments are adopted to validate the variation rule of hardness
and fracture toughness in different orientation of KDP crystal plane (100), and a model to calculate
critical cutting thickness of brittle-ductile transition is proposed for the KDP crystals. The result
shows that, on the crystal plane (100), the minimum value of critical cutting thickness of KDP
crystal in brittle-ductile transition appears in the direction [110], but the maximum appears in the
direction [010]. Finally, the ultra-precision machining of KDP crystal is performed, and the results
agree well with the theoretical conclusions. Super-smooth surface with a roughness RMS of 6.6nm
is reached as machined in the crystal direction [010], and 11.2nm to the direction [110].
Calcium Phosphate Hybridized with Human Semitendinosus and Gracilis Tendon Grafts
Authors: Kobayashi Shinobu , Sakane Masataka , Mutsuzaki Hirotaka , Nakajima Hiromi , Tanaka M. , Miyanaga Yutaka , Ochiai Naoyuki
Published: March 2009

We hybridized calcium phosphate (CaP) with human semitendinosus and gracilis
(ST/G) tendon grafts using an alternate soaking process. To evaluate quantitatively and
histologically assess the CaP hybridized human ST/G tendon grafts, we classified them into
three groups according to their soaking time – number of soaking cycle: 30 sec – 20 cycles
(Group A), 1 min – 15 cycles (Group B), 3 min – 5 cycles (Group C). The tendon grafts were
divided into three parts: tibial end (TE), femoral end (FE) and intra-articular (IA) portion. TE
was secured using the Krackow technique with No. 2 nonabsorbable sutures, and an
Endobutton-CL (Smith & Nephew, USA) was passed through the looped FE, as performed
clinically. Then, the IA portion was covered with the sleeve of a rubber glove to prevent CaP
hybridization. More soaking cycles induced greater deposition of CaP in the tendon grafts
when the total soaking time was the same. Covering the IA portion with a rubber sleeve
prevented of CaP deposition. A large amount of CaP in TE was deposited because suture holes
increased the total contact area with the solutions.
Effects of Mechanical Strain on Osteoblastic Precursor Cells in a Three-Dimensional Scaffold
Authors: Zhao Zhi He , Wang Jun , Fan Yu Bo , Luo Song Jiao , Jiang Ling Yong
Published: March 2009

It was well recognized that mechanical strain plays a crucial role in periodontal tissues
remodeling. The aim of this study was to investigate the effect of mechanical strain on osteoblastic
precursor cells in a collagen type I gel scaffold. Rat MSCs were isolated and cultured according to
the established method. Cells were induced with osteogenic medium, then seeded in a collagen type
I gel and mechanically stretched by application of cyclic biaxial strain 24h later. Strain cycle was set
to 1 cycle/min (0.017Hz), and strain magnitude was set to 2%, 5%, 7% elongation. Cells were
collected in 0h, 3h, 6h, 9h, 12h, 24h and 48h respectively. ODF and ICAM-1 mRNA were analyzed
by RT-PCR assay. The results shown that 2-7% elongation strain, either dynamic or static, inhibited
ICAM-1and ODF expression of osteoblastic precursors, and the effects were relative tightly to strain
magnitude. The inhibition effects of dynamic strain loading group exceeded the corresponding static
strain. This work suggested that appropriate mechanical strech may suppress differentiation of
osteoclasts through inhibiting expression of ICAM-1 and ODF. Application of mechanical stress
might have a beneficial effect on quantity of generated bone tissue and might be a important factor
in tissue engineering of periodontal tissues.
Effect of High Local Concentrations of Antibiotics on Early Bone Formation with Tooth Ash and Plaster of Paris in the Ovariectomized Rat
Authors: Kim S.G. , Park O.J. , Lim Sung Chul , Bae Chun Sik
Published: March 2009

This studied determined the clinical effect of antibiotic use at the site of bone
defect restoration in patients with osteoporosis, using tooth ash and plaster of Paris in
ovariectomized rats. Forty-eight rats were assigned to four groups randomly and each
group was further divided into 4 and 8 weeks after implantation. Histologic sections of
the defects were obtained after surgery for histomorphometric analysis. Comparing each
week, a significant difference was seen in bone formation by 4 weeks. Compared to
controls, new bone formation increased significantly with tooth ash and saline, tooth ash
and gentamicin, and tooth ash and gentamicin after ovariectomy. Tooth ash and saline
resulted in the best bone formation. The degree of new bone formation was slightly
lower when tooth ash and gentamicin were used compared to when tooth ash and saline
were used. When tooth ash and gentamicin were compared according to ovariectomy,
bone formation was significantly inhibited by ovariectomy at 4 weeks, while no
significant difference was seen at 8 weeks.
Residual Stress Assessment in the Al2O3\Mullite Based Laminated System
Authors: Micele Lorenzo , Brach Mylene , Chalvet Francis , de Portu Goffredo , Pezzotti Giuseppe
Published: March 2009

To improve mechanical properties of mullite, a mullite-Al2O3\mullite laminate composite
was prepared. Lamination generates residual stresses within the structure, measured by piezospectroscopy.
A preliminary and complete piezo-spectroscopic characterization of the Al2O3\mullite
system was carried out. A method to determine the concentration of Al2O3 in the composite by
Raman spectrum was proposed and used to assess the composition of the laminated structure along
the cross section. The experimental results evidenced a gradual change of composition and residual
stress state between the two layer.
Sintering and Dielectric Properties of Excess Bi2O3 Doped BaBi2Nb2O9 Ceramics
Authors: Chung Ho Hua , Yang Cheng Fu , Chung Yi Chang , Kung Cheng Yuan
Published: March 2009

In this study, ferroelectric materials with Bi-layered structure BaBi2Nb2O9 with excess x
wt% Bi2O3 (x=0, 1.5, and 3) are investigated as the main compositions, and the sintering is proceeded
from 1000oC~1100oC. The effect of Bi2O3 on the morphologies, crystal structure, and dielectric
characteristics of BaBi2Nb2O9 ceramics is developed with the aid of SEM, X-ray diffraction, and
dielectric-temperature curves. Dielectric properties are investigated in the temperature of 25oC~
465oC at frequency 10KHz~1MHz. It is found that sintering temperature and Bi2O3 content has no
apparent influence on the Curie temperatures, but they have large influence on the maximum
dielectric constants.
Synthesis and Characterization of Regular Hexagonal NiCo2O4 Nanosheets
Authors: Yang Jun , Li Jian Bao , Lin Hong , Yang Xiao Zhan , Wang Ning , Tong Xu Guang
Published: March 2009

In this article, the spinel NiCo2O4 nanosheets with diameters of 100-200 nm were prepared by calcinations of co-precipitates, which were obtained by co-precipitation method. Different kinds of precipitants, including NaOH, KOH, Na2CO3 and ethanedioic acid aqueous solutions were investigated, and regular hexagonal nanosheets are synthesized only when the precipitant is strong KOH or NaOH solution. The morphology and structure of the hexagonal precursor particles and nanosheets were investigated, and the mechanism of the formation of hexagonal nanosheets is discussed.
Preparation and Characterization of Gallium-Doped Zinc Oxide Nanopowders with High Electrical Conductivity
Authors: Du Shang Feng , Liu J. , Chen Yun Fa
Published: March 2009

Gallium-doped zinc oxide nanopowders with high electrical conductivity were prepared by
calcining the precursor synthesized from ZnSO4·7H2O, GaCl3 and NH4HCO3 by co-precipitation method.
The obtained samples were characterized by FE-SEM, TEM, XRD, XPS and BET techniques. The
precursor particles were in the shape of sheet-like with size about several hundred nanometers. The
electrically conductive zinc oxide particles, in the shape of sphere-like, were about 10~40 nm with low
agglomeration, and the specific surface area was 28.7 m2/g. XRD and XPS results showed that all the
doped Ga exists as the substitution form of Ga•
Zn
in the ZnO system. The volume resistivity of the product
was as lower as 4.5 :·cm.
Properties of Nano-Hybrid Sol-Gel Materials Synthesized from Colloidal Silica-Silane Containing Epoxy Silane
Authors: Na Moon Kyong , Kang Dong Pil , Park Hoy Yul , Ahn Myeong Sang , Myung In Hye
Published: March 2009

Three kinds of colloidal silica (CS)/silane sol solutions were synthesized in variation with
parameters such as different acidity and reaction time. Sol solutions were prepared from HSA CS/
methyltrimethoxysilane (MTMS), LS CS/MTMS and LS CS/MTMS/γ -Glycidoxypropyltri methoxysilane
(ES) solutions. In order to understand their physical and chemical properties, sol-gel coating films
were fabricated on glass. Coating films on glass, obtained from LS/MTMS sol, had high contact angle,
also, much enhanced flat surface in the case of LS/MTMS sol was observed in comparison with HSA/
MTMS sol. From all sol-gel solutions, seasoning effect of for enhancing properties of sol-gel coating
layer on glass was observed while such sol-gel solutions were left for 7days. In initial stage of sol-gel
reaction, all most of sol solutions used in this work seem to be unstable, formation of coating films was a
little hazy and rough. However, improved coating films as observed in 4days later. LS/MTMS/ES sol
solutions were synthesized with ES, adding to LS/MTMS sol. Contact angle of LS/MTMS/ES sol-gel
coating films decreased, since ES played a role in forming hydrophilic hydroxyl sol. The elastic portion of
coating films prepared from LS/MTMS/ES sol increased with addition of ES, but thermal stability
decreased a little.
Phase Transformation Behavior of ZrO2-TiO2 Thin Films in Electric Field
Authors: Mei Le Fu , Liang Kai Ming , Wang Shu Ming , Zhou Feng
Published: March 2009

ZrO2-TiO2 thin films, which were heat-treated with an applied electric field, were prepared by
sol-gel method. The phase transformation behavior of ZrO2-TiO2 composite thin films was studied by
DTA, XRD, SEM and Raman spectroscopy. In an electric field, the phase transformation temperature of
amorphous phase to anatase and that of anatase to rutile are all decreased.
Silicon Nitride Ceramic Prepared by Colloidal Process
Authors: Liu Ming , Xu Li Hua , Bi Yu Bao , Zhang Han , Fu Zhi
Published: March 2009

Advanced silicon nitride ceramic compact was prepared by colloidal process. The rheological
behaviors of the Si3N4 powders were emphatically investigated. At the same time, the effects of the
dispersant, pH value and ball milling time on the silicon nitride slurry were discussed. The results showed
that the addition of the dispersant could shift the value of Zeta potential and improve the fluidity of silicon
nitride slurries. The well fluidity can be achieved when the amount of the dispersant was 1.2wt%. Besides,
a ball milling time of 8h was appropriate. Statistic pattern recognition was used to predict the processing
parameters. Then the high density of green compact could be attained while the volume fraction of solid
powders was up to 40%, and the fracture toughness of the sintered body reached 7.2MPa·m1/2. The
microstructure of final sintered ceramic was observed by scanning electron microscope (SEM).
Lower and Upper Bounds of Mechanical and Thermal Properties of Ceramic/Metal Composites
Authors: Xiao Jin Sheng , Zhan Zhi Gang , Zhao Wen Hua , Fu Wei Biao
Published: March 2009

In this paper, the lower and upper bounds of Young’s modulus and Poisson ratio are determined by the effective stress method and effective strain method from material mechanics. The effective heat flux method based on the hypothesis of equivalent temperature difference and the effective temperature difference method based on the hypothesis of equivalent heat flux are proposed, the lower and upper bounds of the thermal conductivity of ceramic/metal composite material are determined similarly. The result shows that the property values of ceramic/metal composites calculated from current theoretical property formulas are within the lower and upper bounds determined by the above methods.
A Method to Evaluate the Elastic Properties of Ceramics-Enhanced Composites Undertaking Interfacial Delamination
Authors: Chang Hua Jian , Zhan Shu Wen
Published: March 2009

A micromechanical approach is developed to investigate the behavior of composite materials,
which undergo interfacial delamination. The main objective of this approach is to build a bridge between
the intricate theories and the engineering applications. On the basis of the spring-layer model, which is
useful to treat the interfacial debonding and sliding, the present paper proposes a convenient method to
assess the effects of delamination on the overall properties of composites. By applying the Equivalent
Inclusion Method (EIM), two fundamental tensors are derived in the present model, the modified Eshelby
tensor, and the compliance tensor (or stiffness tensor) of the weakened inclusions. Both of them are the
fundamental tensors for constructing the overall constitutive law of composite materials. By simply
substituting these tensors into an existing constitutive model, for instance, the Mori-Tanaka model, one
can easily evaluate the effects of interfacial delamination on the overall properties of composite materials.
Therefore, the present method offers a pretty convenient tool. Some numerical results are carried out in
order to demonstrate the performance of this model.
Application of Hydrogen Peroxide Gas Plasma Method for Porous Polyurethane Sterilization
Authors: Lee Mi Hee , Woo Yeon I , Lee In Seop , Kim Jeong Koo , Park Jong Chul
Published: March 2009

Tissue-engineering must be either manufactured aseptically or sterilized after processing.
To extend protection of medical devices against microbial contamination, various sterilization
methods have been suggested. Hydrogen peroxide gas plasma sterilization has been applied in
hospitals worldwide for almost a decade. In this study, we investigated the sterilization efficacy of
hydrogen peroxide gas plasma sterilizer with porous polyurethane sample. The result is suggested
that hydrogen peroxide gas plasma can be applicable to the sterilization of polymer scaffold for
tissue engineering materials.
Surface Interaction Studies on Glass Fiber Reinforced Polymer Bars
Authors: Lee Jung Yoon
Published: March 2009

The use of fiber reinforced polymer (FRP) bars has been gaining increasing popularity in
the civil engineering community due to their favorable properties such as high-strength-to-weight
ratio and good corrosion resistance. In order for concrete to be FRP reinforced, there must be
interfacial bond between FRP bars and concrete. The interfacial bond behavior of FRP bars to
concrete is expected to vary from that of conventional steel bars, since various key parameters that
influence bond performance are different. This paper presents the results of an experimental and
analytical study on the interfacial surface interaction of glass fiber reinforced polymer (GFRP) bars in
high strength concrete cube. The experimental program consisted of testing 54 concrete cubes
prepared according to CSA S802-02 standard 1). The split specimens showed that interfacial bond
failure of the steel bar occurred due to concrete crushing in front of the bar deformations, while
interfacial bond failure of the GFRP bars occurred partly on the surface of the bar and partly in the
concrete by peeling of the surface layer of the bar.
A Study on Anthropomorphic Robot Hand Simulation Driven by SMA Wire Using Segment Control
Authors: Cha Kyoung Rae , Kim Gwang Ho , Kim Ju Hwan , Jeong Sang Hwa
Published: March 2009

In recent years, as the robot technology is developed, the researches on the artificial
muscle actuator that enables robot to move dexterously like biological organ become active.
Actuators are one of the key technologies underpinning robotics. Particularly breakthroughs of
power-to-weight ratio or energy-density in actuator technology have significant impacts upon the
design and the control of robotic systems. The widely used materials for artificial muscle are the
shape memory alloy and electro-active polymer. These actuators have the higher energy density
than the electromechanical actuators such as the electric motor. However, there are some drawbacks
because these actuators have the hysteretic dynamic characteristics. In this paper, the segment
control for reducing the hysteresis of SMA is proposed and the simulation of an anthropomorphic
robotic hand is performed using ADAMS. A new approach to design and control of SMA actuators
is presented. SMA wire is divided into many segments and their thermal states are controlled
individually in a binary manner(ON/OFF). The basic experiment for evaluating the dynamic
characteristics of SMA wire actuator is performed.
Propagation Characteristic of Elastic Wave in Pipe
Authors: Lee Jin Kyung , Lee Sang Ll , Lee Joon Hyun , Park Young Chul
Published: March 2009

In this study, elastic waves of ultrasonic and acoustic emission were used to evaluate the
propagation characteristic of the wave in pipe, and study on mode conversion of the elastic wave
due to the cracks in the pipe was also performed. An acoustic emission (AE) sensor was used to
receive the propagated ultrasonic wave. AE technique has a merit that it can identify the received
ultrasonic wave by the analysis of the AE parameters such as count, energy, frequency, duration
time and amplitude. For transmitting and receiving of the wave, a wedge for universal angle was
manufactured. The optimum angles for transmitting of ultrasonic wave and signal receiving at the
attached AE sensor on the pipe were determined. Theoretical dispersion curve was compared with
the results of the time-frequency analysis based on the wavelet transformation. The received modes
showed a good agreement with theoretical one. The used ultrasonic sensor was 1MHz, and AE
sensor was broadband (100kHz – 1200kHz). The artificial cracks were induced in the pipe to
measure the propagation characteristics of the elastic wave for the cracks. AE parameters for the
received signals were also varied with the crack types in the pipe. AE parameters of amplitude and
duration time were more effective factors than the analysis of mode conversion for evaluation of the
cracks in the pipe.
Elasto-Plastic Stress Distribution in Triplate Joint Assembly under Bending Moment
Authors: Baek Tae Hyun , Koh Seung Kee , Cheng Jie
Published: March 2009

Pre-produced triplate transition joint assemblies are widely used in shipbuilding industry to
make welds between aluminum and steel for a number of years now. The straight-shaped transition
joint assemblies are bent during shipbuilding. So it is necessary to study the residual stresses created
by punch forming, which would have heavy effects on the quality of structural parts. ABAQUS is a
suite of powerful engineering simulation programs, based on the finite element method. In this paper,
ABAQUS was used as the main tool to simulate the residual stresses in a triplate transition joint after
unloading. Punch-pressing was carried to simulate bending moment in ABAQUS. The triplate is
consisted of baselayer (steel: Lloyd’s Shipplate Gr. A), interlayer (pure aluminum: Al99.5) and
superlayer (Al-Mg alloy: AlMg4.5Mn). Results from the ABAQUS analysis showed that increasing
the radius of punch significantly reduced the von Mises residual stresses in steel. Changes of von
Mises residual stresses in interlayer (Al99.5) and superlayer (AlMg4.5Mn) were negligible.
The Influence of Welding Conditions on Mechanical Properties and Microstructural Change of TIG Welded Joint in Extruded Plate AZ31B Mg Alloy
Authors: Chung Dong Seok , Kim Y.G. , Lee S.H. , Park B.O. , Kim J.K.
Published: March 2009

This present work investigated the influence of welding conditions, such as welding
current, diameter of welding wire on the microstructural change, and mechanical properties of TIG
welded joint in extruded AZ31B Mg plate. It was found that a good and sound welded joint was
achieved in all welding conditions. The grain size decreased with increasing welding current and
decreasing diameter of welding wire. In addition, the second phases were homogeneously distributed
in the grain and grain boundary as the welding current and the diameter of the welding wire were
decreased. β discontinuous precipitates were observed in the welded joint; this microstructure has not
been reported by previous researches investigating AZ31B Mg alloy. The hardness value was affected
by the existence state of the second phase and the hardness of the welded joint region was lower than
the other regions in welded AZ31B Mg alloy. The strength of the welded joint region was influenced
by the grain size and had more than 90 %, compared to that of ASTM standard specification.
Wide-Gap Brazing of IN738 and the Bonding Strength Using Ni-Based Filler Metal Powders
Authors: Kim Yong Hwan , Kim Il Ho , Kim K.T. , Shin Seung Y.
Published: March 2009

The microstructure and bonding strength of the wide-gap region brazed with different filler
metal powder (BNi-3 and DF 4B) and various powder mixing ratios of additive powder to filler metal
powder were investigated. The microstructure characterization showed that Cr borides with a blocky
morphology were existed in the brazed region in both filler metal powder. The bonding strength of the
wide-gap region brazed with 60 wt.% IN738 additive and 40 wt.% DF 4B powder exhibited 92%
tensile strength of IN738 superalloy at room temperature. The Cracks in the wide-gap brazed region
initiated at the intermetallic compound and eutectic structure, and then propagated through them.
Viscoelastic Analysis of Adhesively Bonded Double – Lap Joint
Authors: Lee Sang Soon
Published: March 2009

In this paper, stress distribution in a double lap joint subjected to a tensile load is
investigated using the boundary element method. The adhesive used in this study is a commercial
epoxy system which can be cured at room temperature. The adhesive is assumed to be linearly
viscoelastic. The order of the singularity is obtained numerically for a given viscoelastic model. The
numerical results show that interface stresses are large enough to initiate local yielding or edge cracks.
Since the exceedingly large stresses cannot be borne by the adhesive layer, edge cracks can occur at
the interface corner.
Process Design of Profile Ring Rolling for Turbine Diaphragm Using FEM Simulation
Authors: Yeom Jong Taek , Jung Eun Jeoung , Kim Jeoung Han , Lee Dong Geun , Park Nho Kwang , Choi Seung Sik , Lee Chong Soo
Published: March 2009

The process design of profile ring rolling for a large-scale turbine diaphragm was made
using the calculation method and three dimensional finite element method (FEM). The design criteria
are to achieve uniform distributions of strain and temperature, and defect-free profiled ring products.
Based on the compression test results of the low alloy steel, deformation processing map was
generated using the combination of the dynamic materials model (DMM) and stable or unstable
forming criteria. The processing map was used to determine the optimum ring rolling temperature and
feed rate of the mandrel. FEM analysis was simulated to predict the formation of rolling defects and
deformed shape in the profile ring rolled diaphragm product. Finally, optimum process design to
obtain a sound large-scale turbine diaphragm without forming defects was suggested and its
validation was made by the comparison between the experimental data and FE analysis results.
Tensile Test Techniques for a Nuclear Fuel Cladding in a Hot Cell
Authors: Kim Do Sik , Ahn Sang Bok , Oh Wan Ho , Yoo Byung Ok , Choo Yong Sun , Hong Kwon Pyo , Kim Sun Kee
Published: March 2009

Modified transverse and longitudinal tensile test techniques are proposed to evaluate the
mechanical properties of nuclear fuel cladding materials under a hoop and axial loading condition in
a hot cell. The ring specimen with a gage length of 3 mm and a width of 2 mm is designed to limit a
deformation within the gage section and to maximize the uniformity of a strain distribution at the
gage section. The loading grip is designed such that a constant curvature of a specimen is
maintained during a deformation. The contact surface is lubricated with a graphite lubricant (Model
P-37, Molykote Co.). A dogbone specimen with a gage length of 25 mm and a gage width of 2.5
mm has been designed for the longitudinal tensile test. The grip is designed such that any slippage
at the gripping section does not occur during a test. Through the tensile test of an unirradiated
Zircaloy-4 cladding tube and an SUS 316 steel seamless tube, it is found that the proposed
techniques are appropriate for an estimation of the tensile properties of an irradiated nuclear fuel
cladding in a hot cell.
Effect of TMT Process on the Strength and Precipitation Behavior of an 11Cr-0.3Mo-1.6W Steel during Long Term Aging
Authors: Song Sang Min , Jung Woo Sang , Hong Suk Woo , Bae Deuck Seung , Chung Soon Hyo , Kwun S.I.
Published: March 2009

The effect of thermo-mechanical treatment (TMT) process on the strength and precipitation
behavior of an 11%Cr-0.3Mo-1.6W steel during long term aging was investigated. The major
precipitates in as-tempered specimen were identified as M23C6 (M=Fe,Cr) and MX (M=Ta,V;X=C,N).
The M23C6 precipitate in TMT sample was more finely distributed due to the increased heterogeneous
nucleation sites at dislocations. The tensile strength of TMT sample is higher than that of the
conventional heat treatment (CHT) sample in as-tempered condition. However, Laves phase starts to
precipitate additionally in the aged condition. The growth rate of Laves phase in TMT sample is much
faster than that in CHT sample. Therefore, the difference in tensile strength between CHT and TMT
sample decreases as the aging time increases.
The Main Effect of Design Variables for a Safety Valve on a Fracture Pressure
Authors: Lee Sang Woo , Shin Dae Young , Chun Kyoung Jin
Published: March 2009

The safety valve has been designed to protect high pressure vessels. A fracture plate made
of a circular thin plate is located within the safety valve. The circular thin plate has an outlet for fluid
release and to help decrease the pressure. As such, fracture of the circular thin plate can occur at the
appointed pressure. In this study, design variables of the safety valve were used to control fracture
pressure so that it was easy to apply in the development of a new model of a safety valve. Design
variables were fluid diameter of the safety valve, thickness of the fracture plate, filet radius of the
clamping bolt, fracture pressure, and clamped torque of the clamping bolt. Design variables were
selected, since the fracture experiment indicated that these variables might play a critical role in the
fracture of the circular thin plate. Fracture pressure was calculated by the finite element analysis
method and analyzed to affect the design variables on the fracture pressure. Using regression analysis,
main design variables such as the fluid diameter, the thickness and the fillet were selected and the
relationships of the variables were expressed by a regression equation. Furthermore, finite element
analysis method and the regression equation were verified comparing with the experiment result.
Syntheisis and Characterization of Bismuth Tungstate Crystals by Solution Growth Technique
Authors: Nishida Masaya , Takeda Hiroaki , Nishida Takashi , Shiosaki Tadashi
Published: March 2009

Growth of ferroelectric Bi2WO6 (BWO) mono-domain bulk crystals was attempted by the
vertical-Bridgman (VB) method below the phase transition (ferro- to paraelectric) temperature of
940oC using Li2B4O7 as a flux. In this method, Pt crucibles with different shapes were used. The
crucible with a wedged tip bottom produced BWO crystal with a thickness of over 4 mm along the
crystallographic c-axis (perpendicular to the spontaneous polarization axis). Using BWO
mono-domain crystals grown by slow cooling technique, on the other hand, their electric properties
were characterized. The dielectric constants, ε
ij, and electromechanical coupling factor, k33, of the
crystals were 70-100 and 36% at room temperature, respectively.
Fabrication and Mechanical Properties of In Situ Monazite-Coated Alumina Fiber-Reinforced Alumina/YAG Composites
Authors: Matsukawa Kozue , Imai Masamitsu , Yano Toyohiko
Published: March 2009

Monazite(LaPO4)-coated alumina-fiber/alumina-YAG (Y3Al5O12) matrix composites were fabricated by in-situ coating of monazite followed by hot-pressing, and the effects of coating and sintering condition on mechanical properties of the composite were examined. Alumina powder and YAG powder (weight ratio, 95:5) were used as raw materials for green sheets, which was fabricated by tape casting technique. Monazite was synthesized by the in-situ reaction of La(NO3) solution with H3PO4 on the surface of fibers. After slurry infiltration into the coated fiber bundles, the fiber cloths were laminated with the green sheets alternately, then they were heat-treated, finally sintered by hot-pressing at various temperatures. The mechanical properties of the composites were changed by the fabrication conditions. Non-brittleness of the composites reduced with the increase of sintering temperature. The composites sintered at 1200oC showed the highest Weibull modulus and pseudo-ductility.
In Vitro Synthesis of Calcium Nanoparticles Using the Protein Cage of Apoferritin
Authors: Fukano Hiroko , Aizawa Mamoru , Yoshimura Hideyuki
Published: March 2009

Recently the creation of calcium compounds with a highly controlled ultrastructure is
noted as next generation materials for biomedical applications. Here we propose the novel method
for synthsizing calcium nanoparticles using iron strange protein, apoferritin. Apoferritin was
incubated in saturated Ca(HCO3)2 solution at 18 °C. Temperature of the reaction solution was then
increased to 37 °C and left for 2 hours to make CaCO3 sedimentated. After removing the sediments
in the bulk solution by centrifugation, the supernatant was concentrated. Saturated Ca(HCO3)2 was
added to it and the mixed solution was incubated at 37 °C for 30 min. This process was repeated
four times. With a Transmission Electron Microscope (TEM), nearly spherical particles with a
diameter of about 6 nm were observed to form in the cavity of apoferritin. The nanoparticles were
observed to have a lattice structure of spacing about 0.22 nm with high resolution TEM. With
Energy Dispersive X-ray spectroscopy (EDS) analysis, the peak of Ca (Kα; 3.7 keV) was detected
from a synthesized nanoparticle. According to the solvent condition, nanoparticles formed in the
apoferritin cavity would be CaCO3.
Carbonated-Apatite/Gelatine Porous Scaffolds for Bone Replacement
Authors: Landi Elena , Martorana Selanna , Tampieri Anna , Guicciardi Stefano , Melandri Cesare
Published: March 2009

A novel foaming method of design and synthesis of porous Carbonate-apatite/gelatine
composite scaffolds is proposed for biomedical applications. Two different suspensions, one
constituted by a biomimetic inorganic phase (B-CHA) and the second by a protein (gelatine), are
mixed, foamed, lyophilized and, in some cases, cross-linked to stabilize the organic phase.
Chemical, morphological and mechanical features of the scaffolds are evaluated. The samples have
chemical composition, compressive and flexural strengths and Young modulus values in the range
of trabecular bone ones. A high interconnected porosity (about 90%) showing a micro- to macrosize
distribution, that is needed for osteoconduction and vascolarization processes in vivo, is also
detected.
The Study of High Speed Turning of the Hardened Mold Steel SKD11 by Ceramic Cutting Tools
Authors: Lin Wei Shin
Published: March 2009

This study discusses the high speed turning of the hardened mold steel by ceramic cutting
tools. From the experiments, we can understand the tool wear condition, tool failure mode and the
surface roughness variation of the workpiece.
In order to understand the tool wear and surface roughness characteristics during the high speed
turning process of the hardened mold steel by ceramic cutting tools, the polynomial network was
used to construct the tool wear and surface roughness prediction model. The polynomial network is
constituted of several function nodes; these function nodes can be self-organizing into the optimal
network structures according to the predicted square error (PSE) criteria.
It is shown that the polynomial network can correctly correlate the input variables (cutting speed,
feed rate and cutting time) with the output variables (tool wear and surface roughness). Based on
the tool wear and surface roughness prediction model constructed, the wear amount of the ceramic
cutting tools and the surface roughness of the workpiece can be predicted with reasonable accuracy
if the turning conditions are given and it is also consistent with the experimental results very well.
The manufacturing engineers can then , according to the prediction results, execute the process
planning, decide the manufacturing process and the tool change time, thus preventing the cutting
tool from being over-worn or failing when it is in use.
Microscopic Three-Dimensional Imaging Theory Based on RIKES
Authors: Guo Li Na , Tang Zhi Lie , Xing Da
Published: March 2009

A novel nonlinear confocal microscopic imaging system based on Raman induced Kerr effect spectroscopy (RIKES) is presented in this paper. The three-dimensional (3-D) microscopic imaging theory is derived with the Fourier imaging theory and nonlinear optical principle. The impact of RIKES on the spatial resolution and imaging properties of confocal microscopic imaging system has been analyzed in detail by the imaging theory. It’s proved that the RIKES nonlinear microscopic imaging system can effectively improve the imaging contrast and provide more characteristic information on Raman spectrum and optical nonlinear Kerr effect, thus greatly improving the imaging quality of confocal microscopic imaging system. It’s shown that the spatial resolution of RIKES confocal microscopic imaging system is higher than that of two-photon confocal microscopic imaging system.
Study of Stray Light and Cross-Talk of the Capillary Array Electrophoresis
Authors: Wang Jie , Wang Li Qiang , Shi Yan , Zheng Hua , Lu Zu Kang
Published: March 2009

Capillary array electrophoresis (CAE) is founded with the laser induced fluorescence detection (LIFD) system. The same model as the detection system is simulated in Tracepro and the stray light caused by capillaries is analyzed. The stray light distribution of the observation surface is plotted when the laser scans the different sections of a capillary in the array. The results of simulation indicate that the stray light is strongest when scanning the inner center of a capillary and decreases at edges; in two cases (50μm and 75μm inner diameter, ID) when the ID is larger, the stray light is stronger as a whole. Different ID of capillaries which affects the stray light is analyzed; considering many factors, 50μm ID of capillary is appropriate. Based on the analysis of stray light cross-talk by other capillaries in an array, the spacing between capillaries in an array is suggested more than 50μm which the stray light is steady-going and simple to operate. The results can be helpful for the mode of the laser scanning different capillaries in an array sequentially.
Modeling and Tolerancing for Complex Aperture Imaging Systems
Authors: Cheng De Wen , Wang Yong Tian , Talha M.M. , Chang Jun
Published: March 2009

To analyze the effects of fabrication and alignment errors on optical systems with
complex apertures such as a segmented telescope, a visual basic routine (VBR) is developed using
CODE V’s COM interface. One of the eminent features of this VBR is its graphical user interface
(GUI). The GUI facilitates the user to model different types of segmentations quickly and precisely.
The input parameters describe the basic shapes of the segments (polygon or sector), the chamfers at
their corners, and the gaps between them. Fabrication errors (i.e. surface errors and alignment errors
such as decenters and tilts for each segment) can also be introduced easily and effectively through
the GUI. Geometrical and diffraction-based analyses can then be performed to study and analyze
the effects of these errors on the imaging quality of the optical system. Results of tolerance analysis
are presented for a test system, which require a very stringent tolerance to be placed on the
discrepancy among the radii of curvature for different segments. In short, the VBR is a user friendly
and a flexible tool with its application scope in designing complex aperture optical systems.
Influences of Alkaline-Earth Metal Oxides on the Properties of Vitrified Bond
Authors: Wang P.F. , Li Zhi Hong , Zhu Y.M.
Published: March 2009

Alkaline-earth metal oxides (MgO, CaO, SrO and BaO) were introduced to Na2O-B2O3-Al2O3-
SiO2 vitrified bond, and their effects on the properties of the vitrified bond were investigated through the
measurements of refractoriness, fluidity and bending strength. The results showed the refractoriness of
the vitrified bond was reduced and the fluidity of the bond increased with the addition of alkaline earth
metal oxides in the order of CaO>SrO>BaO>MgO. When 2-10wt% MgO, CaO and BaO was added into
the bond respectively, the vitrified bond was relatively dense due to high viscosity, and the strength was
all improved to some extent. However, when more than 4wt% SrO was added, the strength decreased
sharply because of the deterioration of microstructure. It was concluded that the bending strength of the
bond was affected by alkaline-earth metal oxides in the order of CaO>MgO>BaO>SrO.
Optical Properties of Ag Nanoparticle-Glass Composites
Authors: Yang X.C. , Li W.J. , Li Z.H. , Wei Y.N. , Huang Wen Hai
Published: March 2009

Silver nanoparticles doped glass composites were prepared by ion-exchange and subsequent
thermal treatment processes. The optical properties of silver nanoparticle-glass composites were
investigated by UV-VIS spectrophotometer and z-scan technique. The results show that the optimal
Ag+/Na+ ion-exchange temperature range is between 310°C and 380°C, higher ion-exchange temperature
or higher AgNO3 concentration in melt or longer ion-exchange period favors the introduction of more Ag+
ions into soda lime silicate glasses. The higher Ag+ concentration introduced into silicate glass, the larger
the volume fraction of Ag nanoparticles in glass after annealing will be. Ag nanoparticles size and volume
fraction become larger with increasing the annealing temperature and extending the annealing time. The
off-resonant third-order nonlinear optical susceptibility of Ag nanoparticle-glass composite exhibits a
value of 1.16×10-10esu where the real part is -1.15×10-10esu, and imaginary part is 1.4×10-11esu.
Tri-Metallic Catalyst for Mass Production of Quasi-Aligned Carbon Nanotubes by Thermal Chemical Vapor Deposition
Authors: Cui Yan Bin , Zhan Shuang Lin , Wu Xiao Feng , Gong Guo Zhuo , Tian Ya Jun , Chen Yun Fa
Published: March 2009

In this paper, mass production of quasi-aligned CNTs was achieved with a new tri-metallic
catalyst (Fe-Ni-Mo/MgO) by thermal CVD method, using methane as carbon precursor. The growth
process was in-situ monitored by thermal gravimetry/differential scanning calorimetry (TG-DSC)
technique, and the yield of CNTs over 2200% was attained under the mixture atmosphere of CH4 and H2
with flow rate about 25 ml/min and 5 ml/min respectively at 900°C for 30 min. The as-prepared products
were characterized. Raman spectrums showed that the CNTs are multi-wall structure. The diameter of the
CNTs was estimated to be 20-30 nm. We think the synergism of FeNi3 alloy and Mo is the main reason for
the high catalytic activity of tri-metallic catalyst.
Corrosion Behavior of SrZrO3@SiO2 Composite in Sodium Hydroxide
Authors: Guo Zhi Min , Bao X.Y. , Zhang Yue
Published: March 2009

SrZrO3@SiO2 composite materials, in which perovskite polycrystalline SrZrO3 was wrapped
by amorphous SiO2, were prepared. The corrosion behavior of the samples was studied under
hydrothermal conditions in 40% NaOH solution. The composite materials were easily corroded in the
sodium hydroxide solution by reason of the presence of a continuous amorphous SiO2 phase. The
corrosion rate increased with the increasing of the porosity because the pores provided channels, via
which corrosion solution could enter into the sample, and increased the contact area between corrosion
solution and the sample. There was a nonlinear relation between the corrosion and time.
Enhanced Mechanism of Fracture Toughness in Cannon Bone
Authors: Chen Bin , Peng X. , Sun S.
Published: March 2009

As a typical biological material, bone possesses high fracture strength and fracture
toughness, which are closely related to its exquisite microstructure. SEM observation of a cannon
bone shows that the bone is a kind of layered bioceramic composite consisting of hydroxyapatite
sheets and collagen matrix. The hydroxyapatite sheets are of long and thin shape, distributing in
parallel. The fracture toughness of the bone is analyzed with the representative model of the
hydroxyapatite sheets and the concept of maximum pullout energy. It is shown that the lathy shape as
well as the parallel distribution of the hydroxyapatite sheets increases the pullout energy and endows
the bone with high fracture toughness.
A Considering Method of Density Distribution Factor for the Ceramic Motor with Soft Magnetic Composite Core
Authors: Cha Hyun Rok , Lee K.S. , Yun Cheol Ho , Son Hyeon Taek , Jung Tea Uk
Published: March 2009

In this paper, we suggested the new standards of motor design in using of Soft magnetic composite (SMC) material. Previous motor design in using of SMC material executed the same procedures of silicon steel. These procedures assumed that all places of material have the same density distribution and B-H curves. But we showed that the SMC material has inequality density distribution. By using powder forming analysis with FEM analysis, we showed that difference of density distribution could not be avoided because of the shear stress on powder, surface of the mold and punch. Therefore the magnetic characteristic was not the same in all places of material. So, we suggested the new method of motor design which considered the inequality density distribution in using of SMC material. And we compared previous method results and new method results and showed the differences of the result values. The density deviation of the SMC motor core was 5.8% and efficiency deviation was 3%. Especially the output value was different above 11% when we got the results by using previous method.
Structural Studies on Ceria-Carbonate Composite Electrolytes
Authors: Hou Zhi Yao , Wang Xiao Di , Wang Jun , Zhu Bin
Published: March 2009

This paper studied structures of ceria-carbonate two-phase composites, with an emphasis on the interfacial structures and interactions between the two constituent phases of ceria and carbonate. The phase structure was analyzed by DSC, XRD and SEM. The IR measurements were carried out to identify the bonding situations and interfaces. Some new absorptions and wavenumber shifts of the bands appeared in IR spectra. There are strong indications of the interfacial phenomena exist in the two-phase composites through comparison between the two-phase composite with each individual constituent phases. The results opened a new interesting subject on the two-phase composite structures with significant importance for applications in advanced low temperature (300-600°C) SOFC.
Preparation and Characterization of Perovskite Pb(Mg1/3Nb2/3)O3-PbTiO3 by a Modified Polymerized Complex Process
Authors: Chen Jin , Fan Hui Qing , Qiu Shao Jun
Published: March 2009

Relaxor-based ferroelectrics, 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 (PMN-PT) with a
pyrochlore-free phase, was prepared by a modified polymerized complex process. The reactive
columbite (MgNb2O6) phase was synthesized by the polymerized complex method at 1050oC for 4 h
with 3wt% excess MgO. Lead acetate and tetrebutyl titanate were used to synthesize pyrochlore-free
PMN-PT powder via the columbite route, from 800oC to 900oC, in air for 4 h. X-ray diffraction and
scanning electron microscopy were used to detect the perovskite phase evolution and the presence of
the pyrochlore phase in PMN-PT. The formation of perovskite PMN-PT is a function of the time and
temperature conditions of the precursor calcinations, and an optimum condition for the thermal
decomposition of the precursor was determined to avoid the formation of the pyrochlore phase.
Preparation of Barium Strontium Titanate Nanopowders by a Sol-Gel Hydrothermal Synthesis Method
Authors: Miao Hong Yan , Ma Jing Yun , Tan Guo Qiang
Published: March 2009

Barium strontium titanate, BST (BaxSr1-xTiO3), nanoparticles were prepared by a sol-gel hydrothermal technique. BST powders of different composition (x=0.1, x=0.3, x= 0.5, x=0.7, x=0.9) prepared by sol-gel technique previously were treated by hydrothermal synthesis method later. XRD results indicated that the as-prepared perovskite BST nanoparticles have the accurate proportioning composition. These results showed that the combination of sol-gel and hydrothermal technique would become a potential and promising process for fabricating BST and other nanopowders.