bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficiency of Gypsum as a Capping Material for the Capturing of Phosphorus Release from Contaminated Lake Sediments
Authors: Kim Seog Ku , Park Yong Jin , Yun Sang Leen , Lee Mi Kyung
Published: March 2009

Lab-scale batch experiments using several 150-L transparent acrylic reactors were
conducted to develop optimum capping materials that can capture phosphorous released from
polluted lake sediments. The sediment used in the experiment was very fine clay (7.7 Φ in mean grain
size), and organic carbon (Corg) content was as high as 2%. Four kinds of batches with different
capping materials; powdered-gypsum (CaSO4·2H2O), granular-gypsum, sand, composite material
(gypsum+sand), and one control batch were operated for 45 days. Phosphorous fluxes released from
bottom sediments in the control batch were estimated to be 4.3 mg·m-2·d-1, while 0.9 mg·m-2·d-1, 1.0
mg·m-2·d-1, 2.2 mg·m-2·d-1, and 0.5 mg·m-2·d-1 in the batch capped with powdered-gypsum,
granular-gypsum, sand, and composite material, respectively. The results obtained from lab-scale
batch experiments show that there were 80% reduction of phosphorous for some materials such as
powdered-gypsum, granular-gypsum, and composite material, whereas sand only about 50%. Increase
in apatite-P fraction (48% → 80%) in the gypsum batches, compared to the control batch, indicates
that abundant Ca2+ and SO4
2- ions from the gypsum added into oxygen-depleted sediment surface
might have supplied abundant oxygen by reducing the sulfate ions very actively, resulting in Ca-P
precipitates.
Evaporation and Stabilization of Heavy Metals with Colloid/Interface Properties in EAF Dust-Clay Bodies
Authors: Wie Young Min , Lee Ki Gang
Published: March 2009

To recycling the EAF dust as a ceramic raw material, the leaching concentrations of
heavy metals (Zn, Pb, Cr, Cd) were analyzed with various pH and mixing ratios for EAF dust-clay
bodies. The evaporation amounts of the some heavy metals were evaluated by measuring their total
concentrations in the sintered bodies of EAF dust-clay mixtures with various mixing ratio and
sintering temperature. TCLP test was conducted for evaluating the chemical stabilities of the heavy
metal elements. The heavy metals in EAF dust are 'amphoteric metal' and leached a little at pH10.
The leaching concentrations of heavy metal ion were effectively decreased by the formation of
PSHP when adding the clay to the EAF dust and controlling the pH of the slurry at 12. Evaporation
of heavy metal components were increased with increasing the sintering temperature and the
contents of EAF dust. The leaching concentrations of heavy metal components were decreased with
increasing the clay content and temperature.
Grain Size and Orientation Control in Lead-Free (Bi,La)4Ti3O12 Thin Film Deposited by Spin-On Method for High Density FeRAM Device
Authors: Kim Young Moon , Jang G.E. , Kim N.K. , Yeom S.J. , Kweon Soon Young
Published: March 2009

A 16Mb 1T1C FeRAM device was successfully fabricated with the lead-free BLT
capacitors. The average value of the switchable polarization obtained in the 32k-array (unit capacitor
size: 0.68 μm2) BLT capacitors was about 16 μC/cm2 at the applied voltage of 3V and the uniformity
within an 8-inch wafer was about 2.8%. But random bit failures were detected during the measuring
the bit-line signal of each cell. It was revealed that the grain size and orientation of the BLT thin film
were severely non-uniform. Therefore, the grain size and orientation was optimized by varying the
process conditions of nucleation step. The random bit failure issue was solved by adopting the
optimized BLT film. The cell signal margin of the optimized FeRAM device was about 340 mV.
Performance of Bismuth Oxide in the Cathaphoretic Epoxy Primers
Authors: Yang Won Seog , Ahn Seung Ho , Seo Jun Sik , Cho Won Seung , Kim Jung Gu , Hwang Woon Suk
Published: March 2009

The anti-corrosion properties of and catalytic effect of crosslinking on Bi2O3
were investigated in this study. The results of double rubs test with methyl ethyl ketone, cyclic
corrosion test and FT-IR with ATR show that Bi2O3 performs anti-corrosion property and catalytic
effect of crosslinking of resin.
Preparation and Standardization of Method for Valuable Metals Analysis in Seawaters
Authors: Yoon Hyeon , Shin Mi Young , Yoon Cheol Ho , Lee Jae Chun , Chung Kang Sup
Published: March 2009

A direct analytical technique was developed and tested for correct estimation of
recovery of Eco-elements such as Li, B, Br, in the seawater, and three processed
seawaters from Hanjoo Co. Ltd. The reliability of recovery technique and the correct
estimation of total recoveries become a major interest before the launch of pilot plant.
High matrix solutions are frequently affected in analyte response during instrumental
analysis as the concentration of major component changed drastically. To overcome
such a complication during standard sample preparation and a better application in pilot
plant, a modified matrix matching standard addition method was developed and the
reliability was checked. The detection limit of elements in several seawaters analyzed
by applying the modified matrix matching standard addition method were 0.144 –
0.258-g/dm3 for lithium, 0.0.013 – 0.18mg/dm3 for boron, and 4.23 – 17.8mg/dm3 for
bromine. The instrumental analysis was carried by AAS for lithium and ICP-AES for
boron and bromine.
Reliability Evaluation of Underfill Encapsulated Pb-Free Flip Chip Package under Thermal Shock Test
Authors: Kim Dae Gon , Kim Jong Woong , Ha Sang Su , Koo Ja Myeong , Noh Bo In , Jung Seung Boo
Published: March 2009

Thermo-mechanical reliability of the solder bumped flip chip packages having underfill
encapsulant was evaluated with thermal shock testing. In the initial reaction, the reaction product
between the solder and Cu mini bump of chip side was Cu6Sn5 IMC layer, while the two phases which
were (Cu,Ni)6Sn5 and (Ni,Cu)3Sn4 were formed between the solder and electroless Ni-P layer of the
package side. A crack was formed at the upper edge region of solder bump, and propagated through
the solder region. The primary failure mechanism of the solder joints in this type of package was
confirmed to be thermally activated solder fatigue failure. After thermal shocks of 2000 cycles, one
more crack which was not observed in the case of non-underfill encapsulated flip chip was observed
at the left side of interface between solder bump and substrate. The addition of this crack formation
should be due to the underfill encapsulation between the Si chip and substrate.
Growth and Microstructure of Gallium Phosphide Nanowires Synthesized by the CVD Method Using Copper Oxide as a Catalyst
Authors: Choi Kyo Hong , Cho Kwon Koo , Kim Yoo Young
Published: March 2009

High purity nanowires are successfully synthesized by chemical vapor deposition. In this
work, we have tried synthesis of GaP nanowires with copper oxide catalyst using chemical vapor
deposition method involving a metal oxide-assisted vapor-liquid-solid (VLS) growth mechanism.
The synthesis process is the same as that described in existing work except for a catalyst. The
mixture of GaP and Ga powder was used as GaP source for synthesis of GaP nanowires. And the
mixture powder was directly vaporized in the range of 700~1000°C under argon ambient in a
furnace. The wire-like products was observed in the range of 800~950°C. The diameter of
nanowires increases with increasing synthesis temperature, but reversely, the length of nanowires
decreases steadily. The nanowires prepared at 850°C possess perfect wire-like shape and uniform
distribution of diameter. The average diameter and length of nanowires are about 50 and 150,
respectively. HRTEM and EDX analysis were carried out to obtain more detailed information of its
microstructure. Nevertheless, all condition of processing was set for making the high purity GaP
nanowires as existing reported method, the nanowires were identified as well-crystallized gallium
oxide nanowires with an amorphous outer layer. It does not accord with existing reported results.
This result means that the catalysts play a key role in the growth of nanowires.
A Study on Supercooling Characteristics of Clathrate Compounds with Concentration of TMA
Authors: Kim Chang Oh , Kim Jin Heung , Chung Nak Kyu
Published: March 2009

Ice storage system that water is used as low temperature latent heat storage material,
refrigerator capacity is increased and COP is decreased because refrigerator is operated at low
temperature due to supercooling of water in the course of phase change from solid to liquid. This
study is investigated the cooling characteristics of the TMA-water clathrate compound including
TMA (Tri-methyl-amine, (CH3)3N) of 20~25 wt% as a low temperature latent heat storage material at
-5°C, cooling source temperature. The results showed that the phase change temperature, the specific
heat is increased and the supercooling degree is decreased as the weight concentration of TMA
became higher. Especially, low temperature latent heat storage material containing TMA 25 wt% has
the average of phase change temperature of 5.8°C, supercooling degree of 8.0°C and specific heat of
4.099kJ/kgK in the cooling process. Phase change temperature higher than that of water and
inhibitory effect against supercooling can be confirmed through experimental study on cooling
characteristics of TMA-water clathrate compound.
Characterization of Automobile Shredder Residues for Chlorine Content and Estimation of it’s Circulation in Cement Kiln
Authors: Kwon Woo Teck , Kim Soo Ryong , Kim Y. , Hwang Jong Hee , Dabhade Vikram V. , Yoo Tae Wook , Bae Seong Youl
Published: March 2009

The possible utilization of automobile shredder residue as a fuel in the cement kiln
process was investigated. The detailed characteristics of the automobile shredder residues were
investigated in terms of it’s chlorine content as a fuel feed and its circulation in cement kiln. For
estimation of the chlorine content in the cement kiln system, the Weber model which is one of the
circulation material’s forecast model was used. From the results, we estimated the chlorine by-pass
rate should be 1 ~ 2 percent, for maintaining the present level of chlorine content’s on the hot-meal
of the cement kiln system.
Degradation of Azo Dyes by the Reduction and Oxidation with Nano Sized Zero Valented Iron
Authors: Moon B.H. , Park Y.B. , Kim Sung Su , Seo Gyu Tae , Lee T.S. , Kim T.S.
Published: March 2009

The objective of this study is to investigate the efficient method to maximize both color and
TOC removal of the azo dye solution by reduction and oxidation with a laboratory synthesized
nano-sized zero valent iron (nZVI). The decolorization efficiency increased with the decrease of pH
and increase of zero valent iron dosage. The optimum dosage of nano-sized zero-valent iron was
20mg/L at pH 3. The surface normalized constant of nZVI was higher than those reported for the
discoloring of azo dye with other ZVIs. The sequential dose of nZVI/H2O2 remove color and TOC
more effectively than the simultaneous dose. Pre-reduction by nZVI could convert azo dye to products
whose oxidation is more degradable and therefore enhances the removal efficiency.
Effect of pH on the Dispersion Stability of Aqueous Ferric Oxide Suspension
Authors: Lee C.H , Lee Eun Hee
Published: March 2009

We have studied the effect of pH on the dispersion stability of aqueous suspensions of
Fe2O3 powders over a wide pH range in the presence of the poly (acrylic acid) (PAA). In order to
investigate the ionization behavior of the PAA, pH of PAA solutions was measured. Sedimentation
and zeta-potential measurements were conducted on aqueous Fe2O3 suspensions to characterize the
dispersion stability of the suspensions. The PAA was ionized over a wide pH range and the quantity of
ionization was abruptly increased at pH > 10. Thus, the dispersion of the Fe2O3 powders was observed
even in acidic solutions and the dispersion stability of the suspensions increased as pH of the solutions
increased. The magnitude of zeta-potential values increased with increasing pH.
Effect of Platinum Pre-Coating on Isothermal Oxidation Behavior of MCrAlY Coating by Plasma Spray Process
Authors: Joo Dong Won , Park Sang Hyun , Jung Yeon-Gil , Lee Je Hyun , Ye Chang Ho , Lee Koo Hyun
Published: March 2009

In this work we have evaluated the effect of platinum (Pt) pre-coating on microstructure
evolution of MCrAlY coating during isothermal oxidation, to improve high temperature oxidation
and corrosion resistance of the nickel-based superalloy MAR M247-DS. Pt was deposited on the
superalloy by electroplating before the MCrAlY coating by a vacuum plasma spray, which was
compared to the superalloy without Pt pre-coating. The samples were subjected to isothermal
oxidation in a box furnace at 1100°C for 25–150 hrs. The weight gain and loss caused by the
oxidation of samples was recorded, and the variation of surface layer and interface morphology were
observed before and after the oxidation tests. The length decrement of cross section is remarkably low
on according to the precipitation of (Ni,Pt)Al phase by Pt pre-coating. Also, the amount of voids at
interface between the coating and the superalloy, which would be introduced as a processing defect, is
reduced by Pt pre-coating.
Effect of Zirconia on the Physical Properties of Cordierite Honeycomb Filter
Authors: Kim Sung Jin , Bang Hee Gon , Moon Jung Wook , Park Sang Yeup
Published: March 2009

The enhancement of physical properties of porous honeycomb filter for air purification
was investigated using cordierite with the addition of pore former and zirconia additive. Because
cordierite honeycomb has porous body, binder formulation was varied using graphite for a pore
forming agent as well as lubricating agent during the extrusion process. Also, the effect of zirconia
additives on the resultant physical properties of honeycomb filter such as porosity, thermal
expansion coefficient and mechanical strength was investigated.
Fabrication and Evaluation of the Novel Elastomer Based Nanocomposite with Pressure Sensing Function
Authors: Han Youn Gyu , Shibata Tomonori , Ramaseshan Rajagopalan , Sekino Tohru , Niihara Koichi
Published: March 2009

A novel organic/inorganic composite material which can work as a pressure sensor has
been synthesized. This composite basically contains nano-sized carbon particles as conductive filler
into an elastomer matrix to achieve pressure sensitive function. The superior pressure sensitive effect
was showed at 0.88vol% of carbon particles while in the previous study the micro-sized carbon
particle was required above 30vol%. In addition, nano-sized silica particles were added to reinforce
electrical insulation properties and to improve the pressure sensing reliability of the composite. The
addition of the surface modified silica improved better both the sensing performance and the
mechanical strength than the composite containing non-modified silica particles. These
polymer-based sensors have economical advantage due to low cost production regardless of the high
performance.
Improved Adhesion to ABS Plastics by a Photocatalytic Reaction
Authors: Kim Gyung Guk , Kang Joung Ah , Kim Seon Jin , Kim Sun Jae , Shin Seung Han
Published: March 2009

The pretreatment of ABS (acrylonitrile-butadiene-styrene) plastics prior to metallization
has been generally performed with strong acids, such as sulfuric, chromic, or
potassium-permanganate acid. However, conventional wet-chemical pretreatment presents inherent
environmental and safety problems to consider. In particular, the presence of Cr+6 imposes a serious
environmental threat. Therefore, in this study, aspects of pretreatment, using the photocatalytic
reaction in TiO2 sol, were investigated as a replacement for wet-chemical pretreatment. Surface
characterization, before and after the pretreatment, was examined by X-ray photoelectron
spectroscopy and scanning electron microscopy. A copper film was deposited by electroless plating,
and the adhesion strength between the deposited film and ABS plastics was evaluated by the cross-cut
tape test (ISO 2409). When ABS plastics were pre-treated in TiO2 sol, the adhesion strength was
improved to levels obtained using a strong acid solution.
Preparation of Nano-Hydroxyapatite/Polyamide6 Composite Porous Scaffold for Bone Tissue Engineering
Authors: Cheng Lin , Li Yu Bao , Zuo Yi , Zhou Gang , Wang Hua Nan , Wang Ming Bo
Published: March 2009

Scaffold in bone tissue engineering must have a three-dimensional (3-D) interconnected
porous structure acting as a template for bone tissue regeneration, and material fabricating the
scaffold must be biocompatible and can provide structural support during bone growth and
remodeling at the same time. In this paper, a method of phase separation and particle leaching
combined (PS/PL) was used to prepare porous scaffold of nano-hydroxyapatite and polyamide6
(n-HA/PA6) composite. The results show that the scaffold prepared by PS/PL has not only
interconnected macropores of 100~300 μm, but also micropores on the walls of macropores, and
PS/PL scaffold is more interconnective in compare with phase separation (PS) scaffold. When the
porosity of the scaffold is about 79%, its compressive strongth is about 3.27 MPa, that is similar to
the human cancellous bone(2~10MPa). Ethanol has some effect on hydrogen bonds, but fabricating
method will not change the chemical component of the composite. The porous scaffold is prospect
for bone tissue engineering.
Preparation of Nano-Sized Ag Metal Colloid by an Advanced Wet-Process Using 3-Mercapto-Propionic Acid
Authors: Tomonari Masanori , Mori Kohsuke , Yamashita Hiromi
Published: March 2009

For the synthesis of the nano-sized Ag metal particle, the sodium borohydride for the
reducing agent was added into the aqueous solution of the AgNO3 with 3-mercapto-propionic acid as
protective agent. Because the surface of nano-sized Ag metal particle was protected by the adsorbed
3-mercapto-propionic acid, the synthesis of the aqueous colloid system with high density became
possible. The negative charge of carboxylate anion protect the aggregation of metal particles in the
solution of high pH value (pH > 5), but the aggregation was occurred in the solution of low pH value
(pH < 2). By changing the quantity of the agent of propionic acid and the pH value of solution, the
particle size can be controlled optionally in the range of 50~200 nm.
Preparation of Properties of Biodegradable Membranes Using Natural Polymer/Clay Nanocomposite for the Application of Dehumidification
Authors: Park Ji Soon , Rhim Ji Won , Na Jae Sik , Nam Sang Yong
Published: March 2009

Biodegradable chitosan/clay nanocomposite membranes were prepared by solution
casting method for the application of dehumidification. The cationic biopolymer, chitosan was
intercalated into clay through cationic exchange and hydrogen bonding process. Diluted acetic acid
was used as a solvent for dissolving and dispersing chitosan into clays. Chitosan was successfully
intercalated into clay and it was confirmed by X-ray diffraction method. Thermal stability and the
mechanical properties of the nanocomposites are characterized by TGA and Universal Testing
Machine. Thermal stability and mechanical properties were enhanced by increasing clay contents in
chitosan/clay nanocomposites. Gas permeation and water vapor permeation properties of the
nanocomposites were measured by time-lag methods. Permeability of N2 gas and water vapor
through chitosan/clay nanocomposite membranes decreased when the content of clay in the
nanocomposite increased.
Properties of Organic/Inorganic Hybrid Material Synthesized from Acrylic Resin and Silane-Terminated CS
Authors: Kang Young Taec , Lee Jin Kook , Kang Dong Pil
Published: March 2009

Organic/inorganic hybrid materials synthesized from acrylic resin and silane-terminated
colloidal silica(CS). The silane-terminated CS was prepared in variation with the kind of silane to
CS. The CS treated with methyltrimethoxysilane(MTMS) and then treated with vinyl
trimethoxysilane(VTMS), 3-glycidoxypropyltrimethoxysilane(ATMS) or 3-methacyloxypropyl
trimethoxysialne(ETMS) by sol-gel method, respectively. The variation of silane-terminated CS
and acrylic resin were hybridized by thermal-polymerization. Thin films of organic/inorganic
hybrid materials were prepared using spin coater on the glass and aluminum sheets. Their contact
angle, surface electric resistivity and thermal resistance improved with the amount of silaneterminated
CS. The contact angle and surface electric resistivity of hybrid thin film with VTMS
were enhanced. The surface of hybrid thin film with VTMS was homogeneous through FE-SEM.
Properties of Transparent Color Coating Glass Fabricated by Sol-Gel Technology
Authors: Lim Tae Yeoung , Park Y.M. , Hwang Jong Hee , Kim Chang Yeoul , Kim Cheol Y.
Published: March 2009

Color sol was fabricated and coated it on glass substrate using sol-gel method. Silicate
sol prepared by the use of commercially available tetraethoxysilane(TEOS), tetramethoxysilane
(TMOS), methoxysilane(MTSO), phenytrimethoxysilane(PTMS) as a raw material of alkoxysilane
family, and C.I. solvent red 122 and C.I. solvent yellow 82 as a organic dye, and C.I. pigment blue
28 and C.I. pigment red 26 as a pigment. Colored thin films were fabricated with changing the
withdrawal speed by dip coating method, and heat treatment at 100~400°C. The visible light
transmittance of colored thin film was measured with UV/VIS spectrophotometer, the surface
hardness measured by pencil test, the surface turbidity measured by haze meter, and the film
thickness was measureded by Alpha-step surface profiler.
Stability Enhancement for Cold Field Emitter for Reliable Operation of the Micro-Column System
Authors: Kim J.H. , Ahn Seung Joon , Park Chul Geun , Kim Ho Seob , Kim Dae Wook , Ahn Seung Joon
Published: March 2009

Recently, the micro-column has been intensively studied as a potential candidate for
next-generation lithography with high-throughput capability. The micro-column has a simple
structure with an electron emitter, micro-lenses, a double octupole deflector, and an Einzel lens. The
structure and performance of the micro-column are dependent on the characteristics of the electron
emitter. The electron emitter should have several prerequisites such as stable emission of electrons,
high brightness and long lifetime. It is also necessary for the emitted electrons to have sufficiently low
kinetic energy, which can be achieved by using a very sharp emission tip. In this work, we made an
extremely sharp tip by electro-chemically etching the tungsten wire in 10 % KOH solution. From the
Fowler-Nordheim plot, the effective radius of the tip was found to be as small as ~12 nm, which is
consistent with the value measured by SEM. We also discovered that the stability of emission can be
enhanced very much through thermal treatment of the tip end by irradiating the Nd:YAG laser pulse
A Study for Synthesis of Nanobelt and Nanowire Nickel Powders by Wet Chemical Method
Authors: Jeon Seung Yup , Chae Eun Ju , Lee Won Ki , Lee Gun Dae , Hong Seong Soo , Yoon Seog Young , Park Seong Soo
Published: March 2009

Ni nanosheet has been prepared at various temperature and time with anion surfactant by
chemical reduction of the nickel ion complexes formed from complexing reagent in a pressurized
vessel. Sample was characterized by the means of an X-ray diffractomer (XRD), a field emission
scanning electron microscopy (FESEM), an energy dispersive X-ray spectrometer (EDS), a
selected-area electron diffraction (SAED) and a high sensitive magnetometer (HSM). The use of
SDBS and sodium tartrate could be a key factor for the formation and growth of Ni nanosheet.
Study on the Precise Alignment of Micro-Lenses in the Microcolumn by Using the Laser Diffraction Pattern
Authors: Ahn Seung Joon , Kim Dae Wook , Kim Ho Seob , Park Chul Geun , Ahn Seung Joon
Published: March 2009

The alignment precision of the electron lenses is one of the most critical factors that
determine overall performance of the microcolumn system including the image resolution and
aberration. Since the lens apertures are usually as small as 5 ~ 300 μm, the alignment is difficult to
carry out, even if the expensive and complicated aligner is used. In this work, we have developed a
novel alignment method using laser diffraction pattern, with which we can easily obtain
high-precision alignment. The images of Cu grid (mesh# 1000) and carbon nanotubes (200-nm
diameter) taken by the microcolumn fabricated by the new alignment scheme has confirmed that the
new method was very simple and useful.
Synthesis of Precipitated Calcium Carbonate Using a Limestone and its Application in Paper Filler and Coating Color
Authors: Cho Sang Hwan , Park Jin Koo , Lee Seung Kwan , Joo Sung Min , Kim Im Ho , Ahn Ji Whan , Kim Hwan
Published: March 2009

Homogeneous precipitated calcium carbonate(PCC) was synthesized by calcinations,
hydration and carbonation of limestone which has been deposited in Danyang, Korea. In the
reaction process, shapes(scalenohedral and cubic) and sizes(0.2~0.3μm and 2.0μm) of the powder
were controlled by reaction temperature. Synthesized PCC was applied to hand-made paper as filler
and coated paper. For the prepared papers, physical/optical properties(brightness, whiteness, opacity,
roughness, gloss, tensile strength, internal tearing strength, stiffness, bursting strength) and
printability(ink gloss, ink set-off, dry pick, wet pick) were characterized
The Effect of Applied Pressure on the Nonlinear Behavior of ZnO Based Ceramics
Authors: Ahn Seung Joon , Kim Y.J. , Kim Yeong Cheul , Min Joon Won , Ahn Seung Joon
Published: March 2009

Chemical composition and uniaxial compressive stress are varied to observe their effect on
the current-voltage behaviors of ZnO based ceramics. Chemical composition variation produces two
kinds of ceramics showing ohmic and nonohmic current-voltage behaviors. The current at a fixed
voltage is increased with the increase of the compressive stress for both ceramics. Ceramics with
nonohmic behavior shows better reversible return of current-voltage curve when the applied
compressive stress is removed from the ceramic than those with ohmic behavior do. We found out an
appropriate chemical composition showing linear relation between current and stress at a fixed
voltage as a potential application of the ceramic material to pressure sensor.
The Study on the Application of FLEC Test in Indoor Building Materials
Authors: Kim Shin Do , Lee Hee Kwan , Kim Chang Hwan , Lee Seo Lim
Published: March 2009

In this study, FLEC testing skill is tested and examined to validate its applicability to the
emission tests for IAQ. FLEC system has advantages to adapt to in-situ conditions for sampling,
which eases the potential error caused by the distorted test conditions in the lab. The test results from
chamber test and FLEC test are also reviewed in this study and the proper guideline to correlate the
FLECT test result to the chamber test result will be also produced.
NOx and SOx Removal by Low Temperature Plasma-Photocatalysts Hybrid System
Authors: Kim Dong Joo , Nasonova Anna , Park Jong Hun , Kang Jin Yi , Kim Kyo Seon
Published: March 2009

We analyzed the effects of several process variables on removal efficiencies of NO and
SO2 by the low temperature plasma process combined with photocatalysts. The cylinder-wire type,
dielectric barrier discharge process for plasma generation was used. The photocatalysts were coated
onto the glass beads by dip-coating method. As the voltage applied to the plasma reactor increases,
or as the pulse frequency of applied voltage increases, the NO and SO2 removal efficiencies also
increase. As the initial NO concentration decreases, or as the residence time increases, the NO and
SO2 removal efficiencies increase.
Thermal Properties of Water-Absorbing and Surface Modified Porous Pavements
Authors: Kim Ree Ho , Lee Sang Ho , Lee Jung Hun , Gee Chae Sung
Published: March 2009

The creation of large impervious surface in urban and urbanizing areas have led to
significant impacts on local climate, which is commonly known as urban heat island (UHI). In this
study, porous pavements made of recycled sludge were examined as a way to control UHI by lowering
the surface temperature. A novel image analysis technique was applied to quantify cooling effect of
porous pavement materials without and with water. Although the porous pavement itself has smaller
heat capacity than the natural soil, supplying water to the pavement decreased its surface temperature.
At its highest point, the difference in surface temperatures without and with water was more than 10
oC. The water was supplied either from the top of the pavement or from the bottom of the pavement
using the capillary effects. In both cases, pavement temperature was effectively lowered. The cooling
effect of pavement by surface coating using epoxy-based polymers was negligible because surface
pores were blocked. Field tests also confirmed the cooling potential of porous pavements.
Preparation of Si-B-C System Powder Using Silicon, Boron, and Boron Carbide
Authors: Hwang Geum Chan , Matsushita Junichi , Lee Jae Jeong
Published: March 2009

Boron carbide composites in Si-B-C System have been widely studied and applied in
excellent engineering materials. These materials are usually used at high temperature. Unfortunately,
amorphous Si-B-C ceramics have been few reports regarding the properties of Si-B-B4C ceramics.
In this study, the preparation of crystallized Si-B-C system compounds using Si, B, and B4C
powders was investigated to determine their potentially for applications as high hardness
composites. The samples were prepared at 1673 K for 2 hours in Ar atmosphere. The sintered
bodies were cut into 5 х 5 х 10 mm blocks and polished with diamond disk for Vickers hardness.
The samples were subjected to X-ray diffraction (XRD) analysis for phase evolution using a powder
X-ray diffractometer. The fracture surfaces of the specimens were observed using a scanning
electron microscope (SEM) included an energy dispersive X-ray fluorescence spectrometer (EDX)
system to estimate the microstructures.
A Study on the Electrochemical Properties of PEO-Carbon Composite Polymer Electrolytes for Lithium/Sulfur Battery
Authors: Choi Young Jin , Kim Sung Hyun , Park Sang Choul , Shin Dong Hyun , Kim Dong Hun , Kim Ki Won
Published: March 2009

In this study, we investigated ionic conductivities of the electrolytes and cycle
performances of Li/S cells using the electrolyte. (PEO)10LiCF3SO3 composite polymer
electrolyte(CPE) containing carbon powders and Brij dispersant was prepared by ball milling for
12hr. The 5wt% carbon powders having high surface area (~ 80 m2/g) was added into the
(PEO)10LiCF3SO3 electrolyte. To get a well-dispersed structure, Brij dispersant was also added into
the (PEO)10LiCF3SO3-5wt%Carbon electrolyte. Li/CPEs/50wt%S cells showed initial discharge
capacities of between 1,250 and 1,413 mAh/g-sulfur with current density of 100 mA/g-sulfur at
80 °C. These results led us to conclude that the dispersants added into the CPE improved the initial
discharge capacities and cycle performances.
Characteristics of Fluorine-Doped Tin Oxide Thin Films on Poly Ethylene Terephthalate (PET) Substrate
Authors: Kook Yun Ho , Park Ji Hun , Byun Dong Jin , Lee Joong Kee
Published: March 2009

Fluorine-doped tin oxide (FTO) films on PET (Polyethylene Terephthalate) substrate
were prepared by the electron cyclotron resonance-metal organic chemical vapor deposition (ECRMOCVD)
under an Ar-O2-H2 atmosphere. The used tin and fluorine precursor are TMT
(tetramethyltin) and sulfur hexafluoride (SF6), respectively. The hydrogen content plays an
important role to control the optical and electrical characteristics of the films. The HF etching effect
was clearly observed with increase of H2/TMT mole ratio, on the other hand the hydro-carbon
deposition increased with decrease of H2/TMT mole ratio. Therefore the optimum H2 content can be
determined by the counter balance effect between HF etching and hydro-carbon deposition. The
obtained optimum SnO2: F thin films exhibited over 90 % of optical transmittance at wavelength
range from 380 to 780 nm and c.a. 6×10-3 ohm ·cm of electrical resistivity at 1.25 H2/TMT mole
ratio.
Performance of Photocatalytic Microfiltration with Hollow Fiber Membrane
Authors: Jung Jong Tae , Kim Jong Oh , Choi Won Youl
Published: March 2009

The purpose of this study is to investigate the effect of the operational parameters of the
UV intensity and TiO2 dosage for the removal of humic acid and heavy metals. It also evaluated the
applicability of hollow fiber microfiltration for the separation of TiO2 particles in photocatalytic
microfiltration systems. TiO2 powder P-25 Degussa and hollow fiber microfiltration with a 0.4 μm
nominal pore size were used for experiments. Under the conditions of pH 7 and a TiO2 dosage 0.3
g/L, the reaction rate constant (k) for humic acid and heavy metals increased with an increase of the
UV intensity in each process. For the UV/TiO2/MF process, the reaction rate constant (k) for humic
acid and Cu, with the exception of Cr in a low range of UV intensity, was higher compared to that
of UV/TiO2 due to the adsorption of the membrane surface. The reaction rate constant (k) increased
as the TiO2 dosage increased in the range of 0.1~0.3 g/L. However it decreased for a concentration
over 0.3 g/L of TiO2. For the UV/TiO2/MF process, TiO2 particles could be effectively separated
from treated water via membrane rejection. The average removal efficiency for humic acid and
heavy metals during the operational time was over 90 %. Therefore, photocatalysis with a
membrane is believed to be a viable process for humic acid and heavy metals removal.
Design of Manufacturing Process of Oxygen-Free High Conductivity Copper Using Mahalanobis-Distance Outlier Detection Method
Authors: Lee Jung Il , Lee Joo Ho , Park Seung Hwan , Choi Han Shin , Cho Hoon , Jo Hyung Ho , Kim Skae K. , Kwon Hyuk Chon , Hong Jung Eui
Published: March 2009

The proper control of total impurities and oxygen contents of oxygen-free high
conductivity (OFHC) copper prepared by vacuum high-frequency melting technique was studied
using Mahalanobis-Distance (MD) outlier detection method as functions of raw material purities,
vacuum pressure, melting temperature and holding time. The properties of vacuum-melted OFHC
copper was examined by thermo-gravimetric analysis, differential scanning calorimetry, hardness
test, macro and optical microstructure analyses and ultimate tensile test. In multivariate systems, the
existence of outlier makes it difficult to analyze the system and oultier detection belongs to the most
important tasks in experimental data analysis. Mahalanobis Distance is most commonly used as a
diagnosis of existance of outlier in multivariate system. The relationship between experiment
conditions and total impurities and oxygen contents can be defined with the regression analysis
results. At this research, our desirable manufacturing conditions is to obtain the total impurities
under 40 ppm and oxygen contents under 5 ppm. After this statistical approach, the suggested
minimum maufacturing conditions are the purity of raw material was 4N, vacuum pressure was 10-1
torr, melting temperature was 1150°C and melt holding time was 20 minutes.
Development of Honeycomb-Type Solid Oxide Fuel Cell Consisting of LaGaO3 Electrolyte
Authors: Zhong Hao , Matsumoto Hiroshige , Ishihara Tatsumi , Toriyama Akira
Published: March 2009

La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) -based honeycomb cell was first time successfully built
and operated in the case of single-wall used condition and the full 4-walls cell one. Power
generation characteristic of this honeycomb cell was measured from 700°C to 900°C by using
various electrochemical techniques including polarization, current interruption and impedance
spectrometry. The LSGM honeycomb cell shows the exact high power density compared with the
ZrO2 based cell at the operating temperature range, and its value is 394 and 252 mW/cm2 at 800°C
and 700°C, respectively. Thermal stability of this honeycomb cell is also studied and it is seen that
the good performance through several times thermal cycling is observed. The 4-walls’s cell stack is
successfully working at 800°C, and the volumetric power density is achieved to a value of about
700 mW/cm3.
Electrically Conducting Silk Fibroin Microspheres by Incorporation of Multiwalled Carbon Nanotubes on their Surfaces
Authors: Yoon Seok Ho , Kang Min Sung , Kim Hun Sik , Jin Hyoung Joon
Published: March 2009

Electrorheological (ER) particles were obtained by the adsorption of multiwalled carbon
nanotubes (MWCNT) on the surface of silk fibroin microspheres. The resulting spherical polymeric
microspheres consist of a silk fibroin core and an MWCNT shell, which is electrically conducting.
The silk fibroin microspheres were prepared by the phase separation of the silk fibroin and
poly(ethylene oxide) (PEO) blend solution, and the MWCNT dispersion was prepared by
ultrasonication with cetyltrimethylammonium bromide (CTAB) surfactant. The ER particles were
prepared using a simple process involving the blending of the silk fibroin microsphere suspension and
aqueous MWCNT dispersion. The morphology of the ER particles was examined by field emission
scanning electron microscopy (FESEM) and their electrical conductivity measured by the four-probe
method was 4.8×10-4 S/cm. The prepared composite microspheres suspended in silicone oil showed
typical ER characteristics, including the formation of a chain-like structure under an applied electric
field (1.9 kV/mm). This phenomenon can be explained by the interfacial polarizability of the
MWCNTs adsorbed on the surface of the polymeric microspheres.
Electrochemical Influence of Collagen Piezoelectric Effect in Bone Healing
Authors: Noris-Suárez Karem , Lira-Olivares Joaquín , Ferreira Ana M. , Graterol Armando , Feijoo Jose L. , Lee Soo Wohn
Published: March 2009

Bone healing and growth are controlled by the rate of deposition of hidroxiapatite (HA).
This process have been so far accredited to the work of osteoblasts, which are attracted by the
electrical dipoles produced either by piezoelectricity, due to deformation of the bone, specially the
collagen in it, or due to outside electrical stimuli. The present work shows that even without
osteoblasts present, the piezoelectric dipoles produced by deformed collagen, can produce the
precipitation of HA by electrochemical means, without catalyzer as in biomimetic deposition. These
findings could clarify the contribution of osteoblasts in bone growth as compared to the
electrochemical action by itself. Further studies ascertaining the osteoblastic activity due to the
electric field are being advanced.
Electrochemical Properties of Perovskite Cathode for Solid Oxide Fuel Cell
Authors: Hiramatsu Go , Hirata Yoshihiro , Sameshima Soichiro , Matsunaga Naoki
Published: March 2009

Gd-doped ceria electrolyte (Ce0.8Gd0.2O1.9, GDC, 700 μm thick), 30 vol% Ni-GDC cermet
anode and perovskite cathode La0.6Sr0.4CoO3 (LSC) or La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) were used to
evaluate the electric power of the cell using 3 vol%-H2O containing H2 fuel at 873 and 1073 K.
Terminal voltage, ohmic resistance and overpotential were analyzed during the operation of the cell.
The maximum power density with LSC and LSCF cathode was 53 and 113 mW/cm2 at 1073 K,
respectively. The ohmic resistance and overpotential at the cathode was smaller for LSCF than for
LSC.
Evaluation on Some Metallic Alloys for SOFC Interconnect
Authors: Chu Chun Lin , Wang Jian Yih , Lee Jye , Lee Ruey Yi , Lee Shyong
Published: March 2009

Five oxidized metallic alloys, namely, Crofer22, equivalent ZMG232, stainless steel
SS430, SS304 and Inconel718 were subjected to oxidation treatment in hot air environment for
various period of time. Then the resulted oxide scale was analyzed by scanning electron microscopy
(SEM), electron probe micro analyzer (EPMA) and X-ray diffraction (XRD). All the five alloys
contain comparable amount of Cr, Mn, Fe, and their surface oxides as analyzed indicate to be Cr2O3
and (Mn, Fe)Cr2O4 spinel compound.
HRTEM Analysis of Aging Electrolytic Low-Ti Al Alloy
Authors: Wang Wen Yan , Xie Jing Pei , Li Wei , Liu Zhong Xia
Published: March 2009

Electronic tensile testing, scanning electron microscope, transmission electron
microscope, X-ray diffractometer and high resolution transmission microscope were employed to
investigate the mechanical properties, microstructure, tensile fracture and morphology of the
precipitated phases of an electrolytic low-titanium wrought 6009 aluminum alloy. Results showed
that the mechanical properties of the electrolytic aluminum sheet were improved by solid solution
treatment incorporating with pre-aging treatment. The tensile strength and extensibility were
enhanced by a factor of 23% and 38% by pre-aging treatment at 150 °C for 5 minutes respectively;
a large quantity of nucleation sites of β˝ phase were generated by pre-aging treatment, which was
propitious to the transformation from solid solution state to GP zone, and the stable size of GP zone
formed during the pre-aging process promoted the precipitation of Mg2Si phase. The Mg2Si phase
was revealed by HRTEM and the crystalline stripes were obtained by Fourier transformation.
Effects of HTCA on Microstructure and Surface Morphology of Porous Anodic Alumina Membrane
Authors: Zhang Wen Jing , Le Yong Kang , Wang Hui , Ou Bin , Mao Jian Wei , Zhang Jian Ping
Published: March 2009

Porous aluminum anodic oxide films fabricated by anodizing in phosphoric acid electrolyte
containing organic acid were investigated by scanning electron microscope (SEM) and Atomic Force
Microscopy (AFM). The results showed that the pores with circular or near elliptical honeycomb
structure did not grow along the processing direction of the matrix and present an optimum ordering.
It also indicated that the adding of the organic acid reduces the defects during the oxide film growing
process and increases the stability and uniformity of the oxide film, and the thickness of the oxide film
is significantly increased.
Structure and Properties of Microarc Oxidation Films on Zinc-Containing Aluminum Alloy
Authors: Xue Wen Bin , Wu Xiao Ling , Du Jian Cheng , Li Xi Jin , Tian Hua
Published: March 2009

The wear and corrosion protective films were synthesized on the LC4 Al-Zn-Mg-Cu alloy
by microarc oxidation (MAO) technique in an alkali-silicate electrolyte. The microstructure and
composition profiles were investigated by scanning electron microscopy and energy dispersive
spectroscopy, and the phase structure was performed by X-ray diffraction. The corrosion resistance of
coated LC4 alloy was evaluated using potentiodynamic polarization curves. The MAO film consists
of γ-Al2O3, α-Al2O3 and amorphous SiO2 phases. The film up to 210 μm contains two layers. The Si
element from electrolyte enriched in the outer layer film. After microarc oxidation treatment, the
microhardness and corrosion resistance of LC4 alloy were improved significantly.
French Research and Development Activities on High-Performance Superalloys for Gas Turbine Components
Authors: Caron Pierre
Published: March 2009

For several decades, strong efforts have been made in France in research and development
activities dedicated to nickel-based superalloys for high-pressure disks and blades. New superalloys
were designed then developed within cooperative research programmes bringing together research
institutes, alloy producers and engine manufacturers. Continuous research activities were carried out
on these alloys in order to perform detailed analyses of the relationships between process parameters,
chemistry, microstructural features, deformation mechanisms and mechanical behavior. Typical
studies are illustrated by examples outlining some recent results.
Effective Protection of Magnesium Melt Surface from Oxidation Using HFC125-Containing Shielding Gas
Authors: You Guo Qiang , Long Si Yuan , Li Rong Fei
Published: March 2009

In accordance with the ignition-prevention mechanism of F-containing shielding gas,
HFC125 (pentafluoroethane) possesses the potential for forming a F-containing dense film on the
surface of a Mg melt to protect it from oxidation and ignition. Importantly, HFC125 has a GWP
(global warming potential) value around one eighth that of SF6, and is one-third the price (in China).
The effect of HFC125, diluted in a nitrogen based shielding gas was examined via systematic
experiments under variable temperature, concentration, and flux. The results showed that a shiny
metallic film instantly formed on the surface of an Mg melt similar to what was observed with SF6.
The protective effect varied with temperature, concentration and flux. The chemistry and structure of
the protective film was characterized by SEM, EDS and XRD, and showed that the film was a dense,
continuous layer of Mg oxide and fluoride. The results obtained lead to a conclusion that HFC125 is
capable of providing effective protection and is, therefore, an ideal alternative to SF6 in terms of
protective effectiveness, reduced GWP and cost.
Effect of Ru on Microstructure of a Single Crystal Nickel-Base Superalloy
Authors: Ma Wen You , Han Ya Fang , Li Shu Suo , Zheng Yun Rong , Gong Sheng Kai
Published: March 2009

The effect of Ru on the microstructure of a high content refractory elements nickel base
Superalloy has been studied in the present investigation. The results showed that, the adding of 3%Ru
did not prevent the precipitation of TCP phase during high temperature exposure, and even
accelerated the formation of TCP phase,however the addition of Ru decreased the growth rate of μ
phase significantly. In addition, the adding of Ru decreased the solving temperature of γ/γ′ eutectic by
5°C, and increased the tendency of γ′ rafting during high temperature exposure.
High Temperature Structure Stability Study on Nb-Containing Nickel-Base Superalloys
Authors: Xie Xi Shan , Dong Jian Xin , Zhang Mai Cang , Fu Shu Hong
Published: March 2009

High temperature structure stability of 2 important Nb-containing Ni-base superalloys
Inconel 718 (Ni-19Cr-18Fe-3Mo-5Nb-1Ti-0.5Al) and Inconel 740 (Ni-25Cr-20Co-0.5Mo-2Nb
-1.8Ti-0.8Al) have been studied on the relationship of microstructure to mechanical properties via
SEM, TEM, SAD, XRD and quantitative determination of precipitated phases by micro-chemical
analysis. The longest exposure times are 50,000hrs at 650°C for Alloy 718 and 4,000hrs at 704°C,
725°C and 760°C for Alloy 740.
The structure instabilities for these 2 Alloys are: 1) strengthening phases γ″/γ′ coarsening; 2)
meta-stable strengthening phases change to stable phase, such as γ″→ δ-Ni3Nb for Alloy 718 and
γ′→ η-Ni3Ti for Alloy 740; 3) embrittling phases formation, such as α-Cr and σ-phase formation in
Alloy 718 and high Si-containing G-phase formation in Alloy 740.
On the base of understanding phase changes at high temperature exposures the structure stability
of Inconel 718 and Inconel 740 has been improved both by minor adjustment of alloys chemistry.
The modifications of Alloy 718 and Alloy 740 are to be developed in the near future.
The Studies of Non-Equilibrium Grain Boundary Segregation in Ni-Base Superalloy
Authors: Xu Ting Dong , Zheng Lei , Wang Min Qing , Qun Deng
Published: March 2009

Some basic principles of non-equilibrium grain boundary segregation (NGS) and their
applications to B, Mg P segregation to boundaries in Ni-base superalloy are reviewed. An attempt is
made to emphasize the evidences of NGS for B, Mg, P in Ni-base superalloy.