• 보험의학회지
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• 제1권1호
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• pp.133-139
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• 1984

In the 2,218 healthy cases-male 1,574 female 644-who were conducted serum examination from May 1st 1983 to November 1st 1983 by the medical selection of Dae Han Kyouk life insurance Co., the results which investigated the HBsAg by using the Reverse Passive Hemagglutination(RPHA) method are as follows; 1. The number of 167 from 2,218 cases proved to be positive, showing 7.52%, the number of 143 from 1,574 male positive, showing 9.08%, and the number 24 from 644 female positive, showing 3.73%. The positive rate of the male was indicated by 5.36% higher than that of the female as the former marked 2.4 times higher distribution than the latter. 2) The positive rate by the type of occupations appears as follows; The highest positive rate group is that of discharger from military service in 1983, the number of 70 from 736 persons marking 9.51% and the next is the merchant 8.79%(8/91), employee of a company markes 8.53%(44/516), high school boy 7.69%(19/247), house wife 5.71%(10/210), carrier woman 3.45%(10/290) and the group of the high school girl records the minimum rate of all, 3.13%(4/128). 3. The positive rate by the age group appears as follows; The highest rate group is that of 31 to 35 years, marking 9.80% positive rate, and the next is $26{\sim}30$(9.3%), $21{\sim}25$(8.01%), $41{\sim}45$(6.96%), $36{\sim}40$(6.9%), those below 20(5.99%), 46 to 50 years shows the minimum rate of all(2.94%) Among the male case, 26 to 30 years shows the highest positive rate by 10.59% and female, 31 to 35 years shows the highest rate by 7.89%. 4. The positive rate by the blood type represents as follows; Blood type A shows 7.30%, type B 7.17%, type O 6.11% and type AB indicates 5.88% in order.

• 자원환경지질
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• 제31권2호
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• pp.111-125
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• 1998

Dispersion, migration and enrichment of environmental toxic elements from the Samkwang Au-Ag mine area were investigated based upon major, minor and rare earth element geochemistry. The Samkwang mine area composed mainly of Precambrian granitic gneiss. The mine had been mined for gold and silver, but closed in 1996. According to the X-ray powder diffraction, mineral composition of stream sediments and soils were partly variable mineralogy, which are composed of quartz, orthoclase, plagioclase, amphibole, muscovite, biotite and chlorite, respectively. Major element variations of the host granitic gneiss, stream sediments and soils of mining and non-mining drainage, indicate that those compositions are decrese $Al_2O_3$, $Fe_2O_3$, MgO, $TiO_2$, $P_2O_5$ and LOI with increasing $SiO_2$ respectively. Average compositional ranges (ppm) of minor and/or environmental toxic elements within those samples are revealed as As=<2-4500, Cd=<1-24, Cu=6-117, Sb=1-29, Pb=17-1377 and Zn=32-938, which are extremely high concentrations of sediments from the mining drainage (As=2006, Cd=l1, Cu=71, Pb=587 and Zn=481 ppm, respectively) than concentrations of the other samples and host granitic gneiss. Major elements (average enrichment index=6.53) in all samples are mostly enriched, excepting $SiO_2$, $Na_2O$ and $K_2O$, normalized by composition of host granitic gneiss. Rare earth element (average enrichment index=2.34) are enriched with the sediments from the mining drainage. Minor and/or environmental toxic elements within all samples on the basis of host rock were strongly enriched of all elements (especially As, Br, Cu, Pb and Zn), excepting Ba, Cr, Rb and Sr. Average enrichment index of trace elements in all samples is 15.55 (sediments of mining drainage=37.33). Potentially toxic elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) of the samples revealed that average enrichment index is 46.10 (sediments of mining drainage=80.20, sediments of nonmining drainage=5.35, sediments of confluent drainage=20.22, subsurface soils of mining drainage=7.97 and subsurface soils of non-mining drainage=4.15). Sediments and soils of highly concentrated toxic elements are contained some pyrite, arsenopyrite, sphalerite, galena and goethite.

• 한국미생물·생명공학회지
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• 제15권2호
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• pp.135-139
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• 1987

Aspergillus 속 균주 MK-24로부터 venom proteinase inhibitor의 생산조건을 검토한 결과 질소원으로서는 유기능질소가 균생육에 있어서는 매우 좋았으나 물질생성에 있어서는 무기능질소보다 못하였다. 무기질소원으로서는 sodium nitrate가 가장 좋은 효과를 보였다. 단소원으로서는 glucose가 대부분 당류와 비슷한 결과를 나타내었고 특히 arabitol, xylitol, salicin 등은 본 균주가 단소원으로 사용치 못하는 것으로 추정되었으며, vitamin 류는 물질생성에 무관하였으며 금속염류로서는 효과적인 것은 없으나, Ag$^+$, Co$^{++}$, $Zn^{++}$ 등은 억제하였다. 배양온도와 pH는 각각 3$0^{\circ}C$와 pH 5가 균의 생육과 저해물질생성에 제일 적당하였고, 단소원과 질소원으로서 glucose 2%, NaNo$_3$ 0.3%을 가한 액체배지에서 7일간 정치배양 하였을 때 저해물질생육이 가장 좋았다.

• 한국표면공학회지
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• 제39권2호
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• pp.49-56
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• 2006

In this study, the movable flame hardening process of 12Cr steel for a uniform hardness and desirable residual stress have been investigated. For this, the temperature cycles have been controlled accurately as a function of the three processing variables, the flame intensity $I_f$, the scanning velocity $V_s$, and the initial flame holding time $t_h$, where the standard surface temperature $T_{s,\;max}$, was maintained at $960^{\circ}C$. The optimized conditions were $V_s=0.68mn/s\;and\;t_h=67sec$ for the $C_3H_8:O_2\;=\;5:20l/min,\;V_s=0.80mm/s$ and $t_h=56sec$ for the $C_3H_8:O_2=6:24l/min,\;V_s=1.01mm/s\;and\;t_h=48sec$ for the $C_3H_8:O_2=7:28l/min,\;and\;V_s=1.15mm/s$ and $t_h=39sec$ for the $C_3H_8:O_2$=8:32 l/min. The optimally flame-hardened surface exhibited uniform distributions of the hardness and residual compressive stress over the treated area with moderate levels of $470{\sim}490HV_{0.2}$in hardness and $-300{\sim}-450MPa$ in residual stress, which were acceptable on the basis of the acceptance criteria of Siemens AG-KWU and GE Power Generation Engineering.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.454-455
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• 2008

태양전지의 효율은 실리콘 자체의 특성에 의해서 결정 되거나 완성된 실리콘을 통해 태양전지를 제조하는 과정에서 웨이퍼의 두께와 도핑 농도의 조절을 통해 효율을 변화 시킬 수 있다. 높은 효율을 갖는 태양전지 설계를 위해 태양전지 시뮬레이터인 AFOS HET 프로그램을 이용하여 태양전지 웨이퍼 두께와 acceptor의 도핑 농도를 조절하였다. 최적화 결과 80nm ZnO, $300{\mu}m$ c-Si(p), 1nm a-Si(i), 1nm a-Si(n), $1{\mu}m$ Ag, acceptor의 도핑 농도 $7\times10^{16}cm^{-3}$ 에서 $V_{oc}$=697.7mV, $J_{sc}$=42.15mA/$cm^2$, $P_{max}$=0.0247W/$cm^2$, FF=83.51%, Eff=24.56%의 고효율을 얻을 수 있다. 본 연구를 통하여 태양전지 설계나 제조 시에 연구비를 절감할 수 있고 높은 효율의 태양전지로 접근할 수 있다.

• 한국안전학회지
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• 제19권3호
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• pp.57-64
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• 2004

This is the study for the removal of a toxic heavy metal ions and the recycling of expanded polystyrene wastes. Thus expanded polystyrene wastes collected from the packing materials of TV or chemicals and dissolved by $80wt.\%$ solvent(N, N-Dimethylacrylamide), electrospun in DC 20kV by power supply. Generally, the electrospinning is a process of manufacture to the fibers of nanosize from polymer solution. Manufactured nanofiber mats by electrospinning were sulfonated by cone.-sulphuric acid with $Ag_2S_O_4$ catalysts for the exchange capacity of heavy metal ions and the properties of structure with sulfonated time investigated by FESEM(Feild Emission Scaning Electron Microscope). The ion exchange capacity of light metal$(Na^+)$, Cd(II) and Ni(II), and by a nanofiber mats were 1.94[mmo1/g-dry-mat), 1.72(mmol/g-dry-mat), 1.24(mmol/g-dry-mat), respectively., and water uptake content showed a similar trend with IEC. and The selectivity coefficients $K^M_H$ of Cd(II), Ni((II) ions showed 0.324, 0.228. respectively.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.141-158
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• 2020

Skin is a major thermoregulatory organ in the body controlling homeothermy, a critical function for climate adaptation. We compared genes expressed between tropical- and temperate-adapted cattle to better understand genes involved in climate adaptation and hence thermoregulation. We profiled the skin of representative tropical and temperate cattle using RNA-seq. A total of 214,754,759 reads were generated and assembled into 72,993,478 reads and were mapped to unique regions in the bovine genome. Gene coverage of unique regions of the reference genome showed that of 24,616 genes, only 13,130 genes (53.34%) displayed more than one count per million reads for at least two libraries and were considered suitable for downstream analyses. Our results revealed that of 255 genes expressed differentially, 98 genes were upregulated in tropically-adapted White Fulani (WF; Bos indicus) and 157 genes were down regulated in WF compared to Angus, AG (Bos taurus). Fifteen pathways were identified from the differential gene sets through gene ontology and pathway analyses. These include the significantly enriched melanin metabolic process, proteinaceous extracellular matrix, inflammatory response, defense response, calcium ion binding and response to wounding. Quantitative PCR was used to validate six representative genes which are associated with skin thermoregulation and epithelia dysfunction (mean correlation 0.92; p < 0.001). Our results contribute to identifying genes and understanding molecular mechanisms of skin thermoregulation that may influence strategic genomic selection in cattle to withstand climate adaptation, microbial invasion and mechanical damage.

• Current Photovoltaic Research
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• 제9권3호
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• pp.75-83
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• 2021

The tunnel oxide passivated contact (TOPCon) structure got more consideration for development of high performance solar cells by the introduction of a tunnel oxide layer between the substrate and poly-Si is best for attaining interface passivation. The quality of passivation of the tunnel oxide layer clearly depends on the bond of SiO in the tunnel oxide layer, which is affected by the subsequent annealing and the tunnel oxide layer was formed in the suboxide region (SiO, Si₂O, Si₂O₃) at the interface with the substrate. In the suboxide region, an oxygen-rich bond is formed as a result of subsequent annealing that also improves the quality of passivation. To control the surface morphology, annealing profile, and acceleration rate, an oxide tunnel junction structure with a passivation characteristic of 700 mV or more (V_oc) on a p-type wafer could achieved. The quality of passivation of samples subjected to RTP annealing at temperatures above 900℃ declined rapidly. To improve the quality of passivation of the tunnel oxide layer, the physical properties and thermal stability of the thin layer must be considered. TOPCon silicon solar cell has a boron diffused front emitter, a tunnel-SiO_x/n⁺-poly-Si/SiN_x:H structure at the rear side, and screen-printed electrodes on both sides. The saturation currents J_o of this structure on polished surface is 1.3 fA/cm² and for textured silicon surfaces is 3.7 fA/cm² before printing the silver contacts. After printing the Ag contacts, the J_o of this structure increases to 50.7 fA/cm² on textured silicon surfaces, which is still manageably less for metal contacts. This structure was applied to TOPCon solar cells, resulting in a median efficiency of 23.91%, and a highest efficiency of 24.58%, independently. The conversion efficiency of interdigitated back-contact solar cells has reached up to 26% by enhancing the optoelectrical properties for both-sides-contacted of the cells.

• 원예과학기술지
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• 제33권4호
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• pp.492-500
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• 2015

본 연구는 한국잔디에 발생하는 주요 병해인 갈색퍼짐병 억제능력을 보인 3가지 길항 미생물의 길항기작과 미생물제제의 개발에 필요한 배양 조건을 밝히는 것이다. 길항미생물들의 길항작용 기작인chitinase, cellulase 및 siderophore생산능 조사에서 선발 길항미생물 모두 chitinase 활성은 없었으나, I-009균주와 FRIN-001-1균주에서 cellulase와 siderophore의 활성이 있어 진균의 외막가수분해 및 경쟁적 길항작용이 있다고 판단하였다. 그러나 YPIN-022균주는 siderophore의 생산능은 확인하였으나, chitinase와 cellulase의 생산능은 없는 것으로 확인되었다. 선발 길항미생물의 실용화를 위해서는 대량 배양이 필수적이므로 배양학적 특징을 탐색하고자 배지, 온도, pH, 배양시간, 탄소원, 질소원, 무기화합물 등의 영향을 조사한 결과 세 균주 모두 LB 배지에서 생육이 가장 왕성하였다. 최적 배양 온도는 I-009와 FRIN-001-1균주는 pH 5-8범위에서 $35^{\circ}C$와 $30^{\circ}C$ 온도로 32시간 및 28시간 배양할 때 각각 균체의 생장이 가장 높았다. Pseudomonas 속의 YPIN-022균주는 $35^{\circ}C$ 배양 온도로 pH 5-9 배지위에서 24시간 배양시킬 때 생육이 가장 높았다. 탄소원으로 1% sucrose, 질소원으로 0.5% 효모추출물, 무기화합물로 0.1% 염화칼륨을 첨가한 배지에서 I-009와 YPIN-022균주의 생육이 가장 좋았으나, FRIN-001-1균주는 탄소원으로 mannitol, 무기화 합물로 인산칼륨 첨가배지에서 생육이 더 양호했다.

• 마이크로전자및패키징학회지
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• 제28권3호
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• pp.17-24
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• 2021

페로브스카이트 태양전지는 용액공정으로 제작되어 공정 중 전구체 조성제어를 통해 밴드갭을 용이하게 조절할 수 있다. 탠덤 태양전지의 상부셀로 활용하여 실리콘 태양전지와 접합 시 30% 이상의 효율 달성이 가능하지만, 페로브스카이트 태양전지의 낮은 안정성이 상용화의 걸림돌로 작용하고 있다. 아이오딘 이온 및 전극 물질 확산이 주된 열화기구로 알려져 있어 장기 안정성을 확보하기 위해서는 이러한 이온 이동의 방지가 필요하다. 본 연구에서는 층간소재와 페로브스카이트 광활성층 사이의 이온이동에 의한 열화현상을 관찰하고, 이를 억제하기 위해 페로브스카이트 소재와 은전극 사이에 버퍼층을 도입하여 소자의 안정성을 확보하였다. 85℃에서 300시간 이상 보관 시 버퍼가 없는 소자는 페로브스카이트 층이 PbI₂ 및 델타상으로 변화하며 변색되었으며 AgI가 형성되는 것을 확인했다. LiF와 SnO₂ 버퍼 도입 시 이온이동 억제 효과를 통해 페로브스카이트 태양전지의 열안정성이 향상되었다. LiF버퍼층 적용 및 봉지를 한 소자는 85℃-85%RH damp heat 시험 200시간 후 효율감소가 발생하지 않았으며 추가로 AM 1.5G-1SUN 하에서 최대출력점을 추적하였을 때 200시간 후 초기 효율의 90% 이상 유지하는 것을 확인했다. 이 결과는 버퍼층 형성을 통한 층간 물질이동 억제가 장기안정성을 확보하기 위한 필요조건임을 보여준다.