• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.109-115
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• 1993

A CdS single crystal was grown by using sublimation method. Lattice constants, $a_{o}$ and $c_{o}$, obtained by using extrapolation were $4.131{\underline{8}}{\AA}$ and $6.712{\underline{2}}{\AA}$, respectively. The carrier density was${\sim}10^{23}m^{-3}$ and the mobility was $2.93{\times}10^{-2}m^{2}$/V sec from measured Hall data at room temperature. The mobility has a increasing tendency in proportion to $T^{1/2}$ from 33 K to 150 K and a decreasing tendency in proportion to $T^{-2}$ from 180 K to room temperature. The short wavelength band peak measured from photocurrent was due to intrinsic transition, and the energy value of this peak was equal to the energy band gap of CdS photoconductor.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.333-340
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• 1997

An analytical method was developed to determine residues of haloxyfop-R and its methyl ester in soils and soybeans using gas-liquid chromatography (GLC) with electron capture detector (ECD). Soil or soybean sample was acidified and extracted with acetone. The extract was then subjected to ion-associated partition to individually separate haloxyfop-R and the neutral methyl ester. One phase containing haloxyfop-R was methylated with $BF_3$/methanol, partitioned to n-hexane and analyzed by GLC/ECD. The other phase containing the methyl ester was further purified by Florisil column chromatography prior to GLC determination. No cross contamination was found between two phases containing each of the acid and methyl ester, thus two compounds can be separately determined as the identical haloxyfop-R-methyl. Overall recoveries of haloxyfop-R from fortified samples averaged 88.2${\pm}$3.9% (n=12) and 88.3${\pm}$4.0% (n=6) for soils and soybeans respectively, and those of haloxyfop-R-methyl showed mean values of 89.2${\pm}$4.0% (n=12) and 85.6${\pm}$5.6% (n=6). Detection limits of both haloxyfop-R and its methyl esterwere 0.005㎎/㎏ and 0.01㎎/㎏ for soil and soybean samples respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3889-3901
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• 2015

This study was examined the effects of social capital influenced on health related quality of life of old-old-elderly of more than 70-year-old. The subjects were 258 people of old-old-elderly of more than 70-year-old who dwell in M city. The first, October 15 to November 15, 2013, the second, December 1 to 30, 2014 were surveyed. The data were analyzed with SPSS Statistics 18.0 and the structural equation modeling of AMOS 21.0. The Sobel test was conducted to analyze the statistical significance of the mediated effects. The factors of health-related quality of life were influenced significantly by gender, education level, whether or not exercise, amount of sleeping time, family can be a help request, relatives can be a help request, general trust. In the results of the test of the research model, social capital was found to directly affect health behavior, and health behavior was found to directly affect health related quality of life. Therefore, social capital was found to indirectly affect health related quality of life. Social capital of old-old elderly of more than 70-year-old can be recognized as one of the factors influencing their health related quality of life. The results suggest that policy should be established to increasing the level of social capital and improved the health related quality of life.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.991-995
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• 1996

Renal size(length, width and height) of rabbits was measured by radiographs and nephrosonograms and compared with actual size. After measuring on the radiographs and nephrograms, both kidneys were removed from the body and actual size was also measured. On radiographs, right kidney was observed at the T13-L2 vertebrae and left kidney was at L2-L4 vertebrae. On nephrosonograms, the renal cortex was visible as small, homogenous echoes that were hypoechoic relative to the surrounding tissues, whereas the renal medulla was anechoic to slightly hypoechoic. The actual length, width and height of the left kidney were $35.84{\pm}3.12(mean{\pm}SD)$, $23.52{\pm}3.21$, $15.11{\pm}2.58cm$, respectively, whereas those of the right kidney were $36.02{\pm}3.42$, $23.69{\pm}3.50$ and $14.13{\pm}3.55cm$, respectively. On radiographs, the length and width of both kidneys were a little magnified(102-104%) when compared to actual size. On nephrosonograms, the length, width and height of bothkidneys were lessened(70-96 %) when compared to actual size. The length and width of kidney were 1.85 and 1.25 times the length of the second lumbar vertebrae on the ventrodorsal view. In correlation and correlation coefficient of body weight with the renal size, the body weight and renal size were significantly correlated with each other other(p<0.01) and the correlation coefficents of body weight with left, right and both Kindneys were 0.748, 0.794 and 0.859, respectively.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.15-22
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• 1988

In this experiment, interactions between light and other factors such as chilling, alternating temperature, moisture, content, oxygen, and seed coat which affect germination of Oenothera lamarckiana Ser. seed were investigated to study the physiological effects of light on the germination. Light induced the initial stage of seed germination before radical protrusion by affecting embryo rather than seed coat even under anaerobic condition or low water potential (-18 bars). This light effect on germinability of seed was suppressed by blue light irradiation and the effect was increased with increment of blue light intensity and irradiation time. However, the blue light effect was reversible. Chilling, alternating temperature, softening of seed coat and light showed promotive interaction in the induction of seed germination. Irradiation of filtered light (monochrome), however, reduced chilling effect on germination. Hydrogen-ion concentration and gibberellic acid treatment had no effect on light or dark germination.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.216-220
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• 2000

Eighty-eight strain3 o~methicillin resistant Stopllylococcus awecis were Isolated from pus (64.7%); spuhm (26.2%), blood, fluid, andurine of 83 patients at Dong-A Hospital in P~~san to invesligate theil-coagulase typ- Ing, and multi-drug resistaut ppattems. The presence of niec A gene confe~~ing melhicillin resistance was tested by polymerase chain reaction (PCR) with uwo mec A gene specific primers using purified clromosonlal DNA as templates. DNA fragments of expected size wel-e detected frorn 86 strains, but not from two strains. !i coagulase typmg, the 86 isolates were assigned to 5 coagulase lypes, I, 11, lll. 1V, VI, VII, VIlI, but there was no isolate helong lo type V. The most abundant coagulase type was type TI(50 %), lollowed by type IV Rest ofthe coagulase types were ininor; ranging fmm 4.5 to 12.5 '% Most of the type I1 ~netlucillin resistant Stapl\ulcorneryiococcus nwem (MRSA) strams were isolated from the generd sulzely ward, but major strains of type IV were Isolated from the otorhinolq~ngology of the hospital's outpatient clinic center. All of the 88 st~nins were sensitive to vancomycin and teicoplanin, but 71 (81%) strains showed multi-drug resitant to penicillin, cephalotl~n, eiythroinycin, gentan~ycin, imipenem, clindamycin, ciprofloxacin and ooxacillin. Yo relationship was found between the antibiotic resistance pattems aud the coagulase typing patterns.

• Korean Journal of Materials Research
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• v.21 no.7
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• pp.384-390
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• 2011

Ti-6Al-4V ELI (Extra Low Interstitial) alloy has been widely used as an alternative to bone due to its excellent biocompatibility. However, it still has many problems, including a high elastic modulus and toxicity. Therefore, nontoxic biomaterials with a low elastic modulus should be developed. However, the fabrication of a uniform coating is challenging. Moreover, the coating layer on Ti and Ti alloy substrates can be peeled off after implantation. To overcome these problems, it is necessary to produce bulk Ti and Ti alloy with hydroxyapatite (HA) composites. In this study, Ti, Nb, and Zr powders, which are biocompatible elements, were milled in a mixing machine (24h) and by planetary mechanical ball milling (1h, 4h, and 6h), respectively. Ti-35%Nb-7%Zr and Ti-35%Nb-7%Zr-10%HA composites were fabricated by spark plasma sintering (SPS) at $1000^{\circ}C$ under 70MPa using mixed and milled powders. The effects of HA addition and milling time on the biocompatibility and physical and mechanical properties of the Ti-35%Nb-7%Zr-(10%HA) alloys have been investigated. $Ti_2O$, CaO, $CaTiO_3$, and $Ti_xP_y$ phases were formed by chemical reaction during sintering. Vickers hardness of the sintered composites increases with increased milling time and by the addition of HA. The biocompatibilty of the HA added Ti-Nb-Zr alloys was improved, but the sintering ability was decreased.

• Korean Journal of Materials Research
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• v.19 no.1
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• pp.28-32
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• 2009

Silicon carbide (SiC) is a promising material for power device applications due to its wide band gap (3.26 eV for 4H-SiC), high critical electric field and excellent thermal conductivity. The Schottky barrier diode is the representative high-power device that is currently available commercially. A field plate edge-terminated 4H-SiC was fabricated using a lift-off process for opening the Schottky contacts. In this case, Ni/Ti dual-metal contacts were unintentionally formed at the edge of the Schottky contacts and resulted in the degradation of the electrical properties of the diodes. The breakdown voltage and Schottky barrier height (SBH, ${\Phi}_B$) was 107 V and 0.67 eV, respectively. To form homogeneous single-metal Ni/4H-SiC Schottky contacts, a deposition and etching method was employed, and the electrical properties of the diodes were improved. The modified SBDs showed enhanced electrical properties, as witnessed by a breakdown voltage of 635 V, a Schottky barrier height of ${\Phi}_B$=1.48 eV, an ideality factor of n=1.04 (close to one), a forward voltage drop of $V_F$=1.6 V, a specific on resistance of $R_{on}=2.1m{\Omega}-cm^2$ and a power loss of $P_L=79.6Wcm^{-2}$.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.521-528
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• 2012

In this study, we analyzed the physical properties of an ethylene oxide adducted amphoteric surfactant such as critical micelle concentration, surface tension, interfacial tension, contact angle, viscosity and phase behavior. The dual function characteristics of an amphoteric surfactant were investigated by determining an isoelectric point, which were attained using zeta potential measurements and quartz crystal microbalance (QCM) experiments. The isoelectric points of DE3-OSA82-AO, DE5-OSA82-AO and DE9-OSA82-AO surfactant systems determined by zeta potential measurements were 6.97, 6.93 and 7.10 respectively and they are in good agreement with the isoelectric point values measured by QCM experiments. The frictional property measured using an automated mildness tester showed that the DE-OSA82-AO surfactant could provide a good softening effect at neutral condition.

• Journal of Life Science
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• v.13 no.4
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• pp.473-480
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• 2003

We analyzed the patterns of mineral ions and growth responses among symbiotic nitrogen fixing legumes by external nitrogen applications under salt gradients. Glycine max, Phaseolus angularis and Albizzia julibrissin showed remarkable growth inhibition above 40 mM NaCl treatments, but Cassia tora did not exhibit any visible injury symptom up to 100 mM NaCl treatments. As to ionic pattern, the $Na^+$ and $Cl^-$contents in leaves of G. max, P. angularis and A. julibrissin progressively increased with higher contents of external salinity. Compared to other plants, C. tora excluded $Na^+$more efficiently and maintained rather constant ionic contents in spite of high salt levels. With a few exception, these 4 legume plants exhibited better growth by the external nitrogen supply rather than the contribution of symbiotic nitrogen fixation only under saline condition.