• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.04a
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• pp.16-16
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• 2000

분무주조법으로 제조된 Al-25Si-(Fe,V) 합금빌렛의 미세조직을 광학현미경, 주사전자현미경, 투과전자현미경으로 분석하였으며, 빌렛내에서 관찰되는 2차상의 형성거동을 정확히 분석하기 위해 over-sprayed 분말의 미세조직을 분무주조 빌렛과 함께 관찰하였다. 먼저 분무주조 빌렛을 표면으로부터 중심부까지 관찰한 결과, 분무주조 빌렛의 미세조직은 표면부 10mm 가량을 제외하고는 매우 균일한 미세조직을 보여주었다. 이에 본 연구에서는 분무주조 빌렛의 표면부와 중심부, 그리고 over-sprayed 분말조직으로 구분하여 각각에서 관찰되는 2차상을 관찰하였으며, 이를 바탕으로 분무주조 빌렛내에 형성된 2차상의 형성기구를 규명하고자 하였다. Over-sprayed 분말의 미세조직은 기지조직내에 균일하게 분포된 침상의 $\delta$-AlFeSi 상과 각형의 Si 입자로 구성되어 있었다. 반면, 분무주조 빌렛의 경우, 그 중심부에서는 기자조직내에 균일하게 분포된 막대형의 $\beta$-AlFeSi과 부정형의 조대한 Si입자가 관찰되었으며, 표면부에서는 부정형의 Si 입자와 함께 막대형의 $\beta$-AlFeSi/$\delta$-AlFeSi 복합상이 관찰되었다. 특히, 빌렛 표면부의 $\beta$-AlFeSi 상과 $\delta$-AlFeSi 상간에는 일정한 방위관계가 존재하였으며, 이러한 결과는 분무주조 빌렛내에 분포된 $\beta$-AlFeSi상들이 분무액적내에 형성된 준안정 $\delta$-AlFeSi 상으로부터 상분해되어 형성되었음을 제시한다. 이상의 분무주조 조직과 over-sprayed 분말의 미세조직으로부터 분무주조 빌렛의 최종 주조조직은 반응고상태의 분무액적 조직에 의해 지배됨을 알 수 있다.r plate)의 단면 미세조직 사진으로써 모재부와 오버레이충을 함께 보여주고 있다. 모재와 오버레이 충간의 경계면은 모재 일부가 용융된 후 웅고하면서 형성됨으로 인해서 도금이나 용사층과는 달리 매우 견고하게 결합되어 있다. 따라서 계면부의 탈락이라는 문 제점은 거의 없어 심한 응력을 받는 기계구조물 및 부품에도 본 기술은 널리 적용되고 있다. 그리고 사진 1에서 알 수 있는 바와 같이 모재와는 전혀 상이한 재료를 자유로이 선택하여 표면 유효층 일부만 오버레이시키며I 주조 및 단조가 불가능한 재료까지도 표면부에 오버레이 시킴으로 서 부품 및 설비의 제조에 있어 재료비의 절감과 제품의 수명이 획기적으로 개선될 수 있다. 그리고 최근에는 도금 빛 용사 둥과 같은 표면처리를 할 경우임의 소재 표면에 도금 및 용 사에 용이한 재료를 오버레이용접시킨 후 표면처리를 함으로써 보다 고품질의 표면층을 얻기위한 시도가 이루어지고 있다. 따라서 국내, 외의 오버레이 용접기술의 적용현황 및 대표적인 적용사례, 오버레이 용접기술 및 용접재료의 개발현황 둥을 중심으로 살펴봄으로서 아직 국내에서는 널리 알려지지 않은 본 기 술의 활용을 넓이고자 한다. within minimum time from beginning of the shutdown.및 12.36%, $101{\sim}200$일의 경우 12.78% 및 12.44%, 201일 이상의 경우 13.17% 및 11.30%로 201일 이상의 유기의 경우에만 대조구와 삭제 구간에 유의적인(p<0.05) 차이를 나타내었다.는 담수(淡水)에서 10%o의 해수(海水)로 이주된지 14일(日) 이후에 신장(腎臟)에서 수축된 것으로 나타났다. 30%o의 해수(海水)에 적응(適應)된 틸라피아의 평균 신사구체(腎絲球體)의 면적은 담수(淡水)에 적응된 개체의 면적보다 유의성있게 나타났다. 해수(海水)에 적응(適應)된 틸라피아의 신단위(腎單位)의 사

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.459-466
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• 2007

In this study, H-type beta zeolites (BEA) having various metals were used as the adsorbent for the removal of sulfur containing odorants. The different adsorbents containing single or bimetals were utilized to investigate the performance in the individual adsorption of TBM and THT odorants or in the competitive adsorption between them by using a continuous adsorptive bed system. The result shows that the pure H-type BEA zeolite exhibited the highest adsorption capacity for TBM compound, but the higher amount of THT was removed and adsorbed on a HBEA adsorbent having Fe, Pd metal and ZnO oxide. In the case of bimetal containing adsorbents, Cu-Zn/HBEA and Fe-Mo/HBEA showed a higher adsorption capacity for TBM.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.19 no.2
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• pp.190-200
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• 2012

Purpose: The purpose of this study was to provide basic data for the development of weight control programs to maintain and promote healthy behavior in women college students by identifying their weight control behaviors and factors that influence these behaviors. Method: Data were collected from 300 women student participants and were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and multiple regression with the SPSS 18.0 program. Result: Weight control behavior showed a significant difference according to participants' gender role identity type. Weight control behaviors were correlated with self-efficacy, body image, objective BMI, and ideal BMI. Factors influencing weight control behavior were self-efficacy (${\beta}$= .449, $p$<.001), secret method for weight loss (${\beta}$= .181, $p$<.001), monthly allowance below 200,000 won (${\beta}$= .156, $p$= .006), weight control support from others (${\beta}$= .124, $p$= .013), eating breakfast (${\beta}$= .119, $p$= .015), and age (${\beta}$= .113, $p$= .023) with R-sq. value of 45.3%. Conclusion: The results of the study indicate that development of interventions for weight control behavior and health education for college women should reflect identified factors influencing weight control behavior and gender role identity.

• Journal of Life Science
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• v.8 no.3
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• pp.348-351
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• 1998

Common DNA fragments of the ${\beta}$-globin gene were observed from six races of the adult common carp: Hybrid-Yamato, Japanese wild type, Mirror, Suwa-Yamato, Scale German, and Saku-Yamato. Chromosomal DNAs isolated from the above six races were digested with restriction endonucleased EcoRI and PstI. The digested fragments were transferred onto nitrocellulose filter and hybridized with a probe of carp ${\beta}$-globin cDNA. Molecular sizes of the hybridized DNA fragments digested with EcoRI were 3.6Kb(Kilo base), 4.3Kb and 15Kb in Hybrid-Yamato, Japanese wild type, Mirror, Scale German and Saku-Yamato carp DNAs. In Scale German and Saku-Yamato carp DNAs, two and one more hybridized DNA fragments were observed, respectively. Molecular sizes of the hybridized DNA fragments digested with PstI were 2.2Kb, 6.5Kb, 7.8Kb and 9.2Kb in Hybrid-Yamato, 2.2Kb, 6.5Kb and 9.2Kb in Japanese wild type, 2.2Kb, 6.5Kb, 7.8Kb, and 13Kb in Mirror, 2,2Kb, 5,5Kb, 6.5Kb, 7.8Kb, 9.2Kb and13Kb in Scale German, and 2.2Kb, 5.5Kb, 6.5Kb, 9.2Kb and Saku-Yamato carp DNA. Therefore, depending on carps, three to six DNA fragments were hybridized with ${\beta}$-globin gene probe. Thus it indicated polymorphysm in the globin gene family of carp.

• Journal of the Korean Ceramic Society
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• v.29 no.3
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• pp.232-240
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• 1992

Densification behavior, microstructural evolution, and mechanical properties of hot-pressed specimens using $\beta$-SiC and $\alpha$-SiC powder with Al2O3 additive were studied. Beta-SiC powder was fully densified as 205$0^{\circ}C$, but $\alpha$-SiC powder was at 210$0^{\circ}C$. The maximum flexural strength and the fracture toughness of the specimen hot-pressed using $\beta$-SiC powder were 681 MPa and 6.7 MPa{{{{ SQRT {m } }}, and thosevalues of specimen hot-pressed using $\alpha$-SiC powder were 452 MPa and 4.7 MPa{{{{ SQRT {m } }}, respectively. The strength superiority of specimen hot-pressed using $\beta$-SiC powder was due to the finer grain size, and higher density. The higher toughness of specimen hot-pressed using $\beta$-SiC powder than $\alpha$-SiC powder than $\alpha$-SiC powder was due to the crack deflection mechanism arised from the difference of thermal expansion coefficient between $\alpha$ and $\beta$-SiC phases which were co-existed in the sintered body.

• Korean Journal of Materials Research
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• v.12 no.5
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• pp.375-381
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• 2002

N-type ${\beta}-FeSi_2$ with a nominal composition of $Fe_{0.98}Co_{0.02}Si_2$ powders has been produced by mechanical alloying process and consolidated by vacuum hot pressing. As-milled powders were of metastable state and fully transformed to ${\beta}-FeSi_2$ phase by subsequent isothermal annealing. However, as-consolidated $Fe_{0.98}Co_{0.02}Si_2$ consisted of untransformed mixture of ${\alpha}-Fe_2Si_ 5$ and $\varepsilon$-FeSi phases. Isothermal annealing has been carried out to induce the transformation to a thermoelectric semiconducting ${\beta}-FeSi_2$ phase. The transformation behavior of ${\beta}-FeSi_2$ was investigated by utilizing DTA, a modified TGA under magnetic field, SEM, and XRD analyses. Isothermal annealing at $830^{\circ}C$ in vacuum led to the thermoelectric semiconducting ${\beta}-FeSi_2$ phase transformation, but some residual metallic $\alpha$ and $\varepsilon$ phases were unavoidable even after prolonged annealing. Thermoelectric properties were remarkably improved by isothermal annealing due to the transformation from metallic $\alpha$ and $\varepsilon$ phases to semiconducting phases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.5
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• pp.484-489
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• 2004

Isolation of phycobiliprotein from S. platensis was performed by using $30-60{\%}$ ammomium sulfate fractionation, Sephadex G-100 gel filtration and DEAE-Sephacel anionic exchange chromatography. Isolated phycobiliprotein was determined to be a c-phycocyanin with a maximum absorption wavelength at 620 nm. This phycobiliprotein consisted of $({\alpha}$ and $({\beta}$ subunit when analyzed through SDS-PAGE. The molecular weights of $({\alpha}$ and $({\beta}$ subunit were 14.5 kDa and 16 kDa, respectively. The native molecular weight of phycobiliprotein through gel filtration was about 100 kDa. These results show that the structure of phycobiliprotein from S. platensis might be aggregated form of $({\alpha}{\beta})_{3}-trimer$.

• The Korean Journal of Nuclear Medicine
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• v.19 no.1
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• pp.127-136
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• 1985

To evaluate change of serum $beta_2-microglobulin$ concentration$(s\beta_2-MG)$ and the usefulness of $s\beta_2-MG$ and $s\beta_2-MG/serum$ creatinine concentration(sCr) ratio in various renal diseases, $s\beta_2-MG$ and sCr were measured in 25 normal controls and 90 patients of various renal diseases(16 cases of glomerulonephritis, 12 cases of acute renal failure, 8 cases of chronic renal failure, 24 cases of nephrotic syndrome, 15 cases of tubulointerstitial diseases and 15 cases of lupus nephritis) using $Phadebas^\circledR$ $Beta_2-Micro$ Test kits. The results were as follows; 1) In normal control, the mean value of $s\beta_2-MG$ was $1.65{\pm}0.41mg/l$ and the mean value of $s\beta_2-MG/sCr$ ratio was $0.14{\pm}0.05$. 2) In various renal diseases, the mean value of $s\beta_2-MG$ was $6.74{\pm}5.47mg/l$. The mean value of $s\beta_2-MG/sCr$ ratio was $0.24{\pm}0.11$ and significantly elevated than that of normal control. (p<0.05) 3) The correlation between $s\beta_2-MG$ and sCr in glomerular and tubulointerstitial disease was log $s\beta_2-MG-0.90$ log sCr-0.48 and its correlation coefficient was 0.78(p<0.05). 4) In glomerular disease, the correlation between $s\beta_2-MG$ and sCr was log $s\beta_2-MG-0.89$ log sCr-0.46(r - 0.76) and in tubulointerstitial disease, it was log, $s\beta2-MG-0.95$ log sCr-0.59 (r-0.87). There was no significant difference between the two groups(p<0.05). 5) Among 32 cases of glomerular and tubulointerstitial disease patients, whose sCr was within normal range, 17 cases showed elevated $s\beta_2-MG$. The mean values of $s\beta_2-MG/sCr$ ratio in these patients was $0.30{\pm}0.14$ and significantly elevated than that of normal control(p<0.05). 6) In 15 cases of lupus nephritis, 12 cases showed elevated $s\beta_2-MG$ with normal sCr and 12 cases showed elevated $s\beta_2-MG/sCr$ ratio. With above results, it was found that the $s\beta_2MG$ can be used as an index of glomerular filtration rate as in the case of sCr and that $s\beta_2-MG/sCr$ ratio can be used as a tool in early detection of slightly decreased glomerular filtration rate and in detection of the renal disease of increased $\beta_2-MG$ production.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.164-172
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• 1996

Background : Transforming growth factor-$\beta$(TGF-$\beta$) may play a role in a variety of fibroproliferative disorders including pulmonary fibrosis via the induction of extracellular matrix accumulation. TGF-$\beta$ not only stimulates extracellular matrix production, but also decreases matrix degradation. Interstial lung diseases have demonstrated marked expression of TGF-$\beta$. Methods : To evaluate the possible role of TGF-$\beta$ in human pulmonary fibrosis, by using neutralizing antibody of TGF-$\beta$ we investigated immunohistochemically the expression of TGF-$\beta$ in the formalin-fixed, paraffin-embedded tissue sections of the 5 normal cases for the control, and a couple of pieces of tissues taken out of 3 cases with idiopathic pulmonary fibrosis, 3 cases with ILD from bleomycin toxicity, 3 cases with ILD from sarcoidosis, and 3 cases with ILD from eosinophilic granuloma. Results : In the 5 normal cases for the control, the TGF-$\beta$ was expressed in bronchial and alveolar epithelial cells. Up-regulation of the TGF-$\beta$ expression was showed in the interstitial fibroblast cells of alveolar septa in 5 pieces and proliferated alveolar pneumocytes in 1 piece among 6 pieces tissues taken out of 3 cases with idiopathic pulmonary fibrosis. Also up-regulation of the TGF-$\beta$ expression was showed in alveolar lining pneumocytes, intra-alveolar mononuclear cells, and epithelioid cells in most of cases of ILD from bleomycin toxicity, sarcoidosis and eosinophilic granuloma. Conclusion : These findings suggest that up-regulation of the TGF-$\beta$are involved in pathogenesis of interstitial lung fibrosis from variety of causes.

• Journal of Applied Biological Chemistry
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• v.52 no.2
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• pp.51-57
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• 2009

To investigate expression patterns of chitinase, ${\beta}$-1,3-glucanase and peroxidase involved in biological control of phytopathogens, three oil seed rapes (Capitol, Pollen and Saturnin) were used. Activities of the enzymes in old leaves were $9.7{\sim}11.8$ unit/mg protein in chitinase, $11.1{\sim}17.3$ unit/mg protein in ${\beta}$-1,3-glucanase and $0.6{\sim}1.7$ unit/mg protein in peroxidase. Activities of the enzymes in roots were $39.2{\sim}49.0$ unit/mg protein in chitinase, $49.9{\sim}62.0$ unit/mg protein in ${\beta}$-1,3-glucanase and $2.4{\sim}3.8$ unit/mg protein in peroxidase. Chitinase and ${\beta}$-1,3-glucanase activity were the highest level in Saturnin leaves and in Capitol roots while activities of those were the lowest level in Capitol leaves. Also, chitinase and ${\beta}$-1,3-glucanase and peroxidase activity were the lowest level in Saturnin roots. Active bands of chitinase isoform in leaves (73, 51, 40, 34, and 29 kDa) and in roots (100, 57 34, and 29 kDa) tissues showed in the SDS-PAGE gel. Active bands of ${\beta}$-1,3-glucanase isoform in leaves and roots (75 and 55 kDa) tissues showed on the SDS-PAGE gel. Active staining of peroxidase showed the strongest level in leaves and roots of Pollen. Active bands of peroxidase isoform in leaves (122, 114, and 93 kDa) and in roots (135, 122, 114, and 93 kDa) tissues showed on the Native-PAGE gel. These results indicated that establishment of expression pattern of enzymes in rape tissues could play as an important role with respect to resistance of plant pathogens in rape.