• 한국산학기술학회논문지
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• 제6권3호
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• pp.261-264
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• 2005

90nm급 게이트로 활용되는 폴리실리콘을 패턴화 하기 위해서 하드 마스크의 채용 등 신공정과 함께 폴리실리콘 자체의 평탄화가 필요하다. 본 연구는 70nm 두께의 LPCVD 폴리실리콘 게이트를 상정하여 열산화막 상부에 기판 전면을 폴리실리콘으로 만들고 쾌속열처리 온도를 달리해가며 40초가 열처리하여 이때의 표면조도의 변화를 광발산 주사전자현미경(FESEM)과 주사탐침현미경(AFM)으로 확인하였다. 폴리실리콘은 $700^{\circ}C\~1100^{\circ}C$ 온도범위에서 표면 응집효과에 의해 고온에서 표면조도가 급격히 증가하는 경향이 있었으며 $700^{\circ}C$-40sec 조건에서 최적 평탄화 효과가 가능하였다.

• 한국산업융합학회 논문집
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• 제9권1호
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• pp.21-27
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• 2006

The laminar burning velocity was measured using a spherical combustion bomb with central ignition. Mixtures with equivalence ratio between 0.6 and 1.2, were tested. The computation was carried out for the burning velocity using premix code of Chemkin program under the unburned gas pressure of 0.5bar-30bar and temperature of 300K-700K at ${\Phi}1.0$. The results showed little difference between these two methods. The burning velocity was decreased by increasing the pressure and increased by increasing the temperature. The burning velocity was predicted by using the following equations $$S_L(m/s) = S_{st}(T/300)^{1.85}(P)^{-0.45}$$ $$(0.5bar{\leq}P{\leq}30bar,\;300K{\leq}T{\leq}700K)$$).

• 대한화학회지
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• 제9권1호
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• pp.41-44
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• 1965

7-Nitroso-8-hydroxyquinoline-5-sulfonate의 Fe(II)錯鹽의 性質을 700$m{\mu}$, $26^{\circ}C$에서 分光光度法으로 調査하였다. 이 錯鹽은 pH6.0에서 가장 큰 吸光度를 나타내며 熱安定度도 대단히 좋다. Ligand나 Fe(III)의 還元에 使用한 hydroxylamine이 過剩으로 存在할때 에도 錯鹽의 生成에 影響을 주지 않는다. 錯鹽의 組成을 몰比法과 連續變化法으로 調査한 結果, 金屬과 ligand의 몰比는 1:3이였다. 檢量線은 實驗한 濃度範圍內에서 Beer의 法則에 따른다.

• Journal of Photoscience
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• 제9권2호
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• pp.70-73
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• 2002

A cyanobacteria-like organism Aaryochloris marina performs oxygenic photosynthesis with near far-red light by the use of chlorophyll d. Reaction center chlorophyll (Chl) of Photosystem (PS) II of A. marina was studied by analysis of millisecond-delayed fluorescence. Delayed fluorescence is emitted by Chi d indicating efficient energy transfer between antenna Chi d molecules and the unknown primary electron donor of PS II. P740 a reaction center Chl of PS I of A. marina is shown to give a dimer type cation, and triplet state with a D value of 245xlO$\^$-4/ cm$\^$-l/ in contrast to the 280-290 xlO$\^$-4/cm$\^$-l/ values of P700 suggesting triplet spins interacting at a 5% larger distance in P740 than in P700.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.753-756
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• 1992

Research was undertaken to determine if relectance (interactance) measured with a portable fiver optic probe (Colormet) can be used to assess porcine fat quality. Soft fat generally had lower interactance than hard fat, p<0.05 from 400 to 700 nm, although interactance spectra of hard and soft fat were similar in shape. At $4^{\circ}C$, interactance from 450 nm to 700 nm at the inner layer of backfat was correlated (p<0.01) with subjective soft fat score (r = 0.06 to 0.70), and with the refractive index (r = -0.62 to -0.65) and melting point (r = 0.59 to 0.60) of heat-extracted lipid. Colormet interactance $L^*$ at $4^{\circ}C$ was correlated (p<0.01) with soft fat score (r = 0.72), refractive index (r = -0.66) and melting point (r = 0.61). Interactance decreased as the temperature of the fat was increased from 22 to $44^{\circ}C$ (p<0.01). Soft fat had lower interactance than fats that were slightly soft, slightly hard and hard at 4, 22 and $40^{\circ}C$, although softness and temperature may interact to affect interactance. These results indicate that soft porcine fat may be detected easily by fiber-optic spectrophotometry.

• 자연과학논문집
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• 제13권1호
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• pp.35-50
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• 2003

점토광물은 첨단소재용 원료로서 석유, 펄프, 비료, 점결제와 페인트 등 사용분야가 다양한 광물이며, 이러한 천연 점토광물을 비교적 간단하게 처리하여 체내에 농축되면 독성과 피해를 일으키는 염료 폐수의 흡착처리 및 흡착 메커니즘에 대해서 조사하였다. 그 결과 유기염료를 흡착처리하기 위한 입상 점토광물제조의 최적조선은 굽기온도 $700^{\circ}C$이며, 점결제인 polyvinyl alcohol 의 량은 25% 이었다. 제조된 입상 점토광물의 pH는 중성이었고 산성 메디움에서의 안정한 pH의 범위는 3~9 사이였고, 비표면적은 $83m^2/g$ 이였다. 제조된 입상점토광물에 대한 유기염료의 흡착량은 산성 메디움에서 좋은 흡착결과를 보였고, 이때 흡착엔탈피는 -3.36~ -0.84 kcal/mol 로 전형적인 물리흡착임을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제47권6호
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• pp.700-708
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• 2019

To verify the possibility of using resistograph to estimate the age of big old living trees, we selected three Zelkova serrata and seven Pinus densiflora in Goesan. The mean diameters at breast height of Z. serrata and P. densiflora were 102 (92-116) cm and 80 (65-110) cm, respectively. The heights measured from the ground using a resistograph ranged at 1.2-4.3 m and 0.6-1.1 m for Z. serrata and P. Densiflora, respectively. The most appropriate needle speed to determine tree-ring boundaries for measuring ring width was 1500 r/min for both tree species. Alternatively, the suitable feed speeds for Z. serrata and P. densiflora were 50 cm/min and 150 cm/min, respectively. From the measured data, the mean numbers of tree rings of Z. serrata and P. densiflora were 57 (43-68) and 104 (93-124), respectively, and the mean tree-ring widths were 4.27 mm (3.18-5.09 mm) and 2.93 mm (2.32-3.34 mm), respectively. A comparison between the time series of tree-ring widths by resistograph and that from the local master chronologies tallied for the heartwood part. Finally, this study showed that resistograph can be used to estimate tree ages when a local master chronology is available.

• 미생물학회지
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• 제47권1호
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• pp.92-96
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• 2011

Rhodococcus sp. strain DK17은 3개의 linear catabolic megaplasmid (380 kb pDK1, 330 kb pDK2, 750 kb pDK3)를 보유하고 있다. Alkylbenzene 분해 유전자군(akbABCDEF)은 pDK2에만 위치하는 반면 phthalate 분해 유전자군의 경우에는 거의 동일한 copy가 pDK2 (ophA'B'C'R')와 pDK3 (ophABCR)에 각각 위치한다. DK17은 최적 성장온도인 $30^{\circ}C$에서 $37^{\circ}C$로 배양온도를 상승시키면 성장이 멈추지만 $30^{\circ}C$로 환원 즉시 다시 성장을 시작하였다. 이는 $37^{\circ}C$라는 온도 조건이 DK17에게 치명적이지는 않지만 스트레스로 작용함을 암시하는 것이다. 또한 $37^{\circ}C$에서 열충격을 받은 일부 세포는 o-xylene (alkylbenzene의 모델 화합물)을 분해 능력을 상실하였다. 열충격 후 200개의 집락을 무작위로 선택하여 pDK2- 또는 pDK3-specific 프라이머를 이용한 PCR과 pulsed-field gel electrophoresis를 통해 megaplasmid의 변화 양상을 비교 분석한 결과, 29개 돌연변이체에서 야생형의 것과 다른 5가지 megaplasmid 유형[pDK2 소실과 함께 새로운 약 700 kb megaplasmid 출현(10개), pDK2만 소실(9개), pDK3 소실과 함께 새로운 약 400 kb megaplasmid 출현(8개), pDK3만 소실(1개), 그리고 pDK2와 pDK3 소실과 함께 각각 약 400 kb와 700 kb 크기의 새로운 megaplasmid 출현(1개)]이 관찰되었다. 이상의 연구 결과는 성장 온도 변화가 세균 유전체의 물리적 변화를 직접 유도할 수 있음을 입증하는 것으로 온도 변화를 비롯한 서식지 환경 변화가 세균 진화에 상당한 영향력을 미칠 수 있음을 보여준다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.631-639
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• 2001

Two experiments were carried out concerning the effects of urea-molasses cake (UMC) and its separate components as supplements on rumen environment, in sacco feed degradability and intake of swamp buffaloes fed rice straw, grasses or a mixture of grasses and rice straw. Experiment 1 was a change-over design with 4 animals and 6 treatments. The buffaloes were fed rice straw ad libitum, and the experimental treatments were: no supplementation (R); 700 g of the complete urea-molasses cake (RUMC); 53.2 g urea (RU); 276 g rice bran and 52.5 coconut meal (RRC); 26.6 g salt, 26.6 g bone meal and 2.1 g trace minerals (RMi); and 25 g molasses (RMo). Experiment 2 was a Latin square design with four diets and four animals. The treatments were: rice straw ad libitum and mixed grass (RG) at 2.5 g dry matter per kg live weight (LW); RG plus 700 g urea-molasses cake (RGUMC); mixed grass ad libitum (G); and G plus 700 g cake (GUMC). In both experiments the supplements were fed once daily. In Exp. 1 although the rumen pH was significantly different (p<0.05) among diets, it varied only from 6.90 to 7.06. The ruminal ammonia was also significantly (p<0.05) different among the diets with RUMC significantly higher than R. Total bacterial and protozoal counts were significantly (p<0.05) higher for the RUMC, RU, RMo and RRC diets. Total feed and rice straw intakes were highest for RUMC (p<0.05) and lowest for the RMi and RMo diets, but in sacco degradability of four different roughages were not significantly different among diets. In Exp. 2, rumen pHs of the diets differed significantly and (p<0.01) ranged from 7.04 - 7.19. Ruminal $NH_3-N$ concentrations (mg/100 ml) were also significantly different (p<0.05), and higher for the RGUMC, G and GUMC diets. The total counts of bacteria and protozoa were significantly (p<0.05) higher for the RGUMC, G and GUMC diets. The total feed intake and roughage intake were significantly (p<0.05) higher for the RGUMC, G and GUMC diets compared to the RG diet. Correspondingly, LW changes also differed among treatments (p=0.06). It was concluded that there were significant increases in rumen $NH_3-N$ concentration, microbial populations and feed intake in the buffaloes by UMC supplementation, whereas the significant difference in in sacco DM degradation was not found by any type of supplementation. There seemed to be a need of a combination of urea, molasses, minerals and other protein nitrogen sources to enhance rice straw intake. Adding grass to the rice straw diet at 0.25% LW (DM) should also be considered to maintain buffalo rumen function and production with UMC supplementation, when rice straw is the main roughage.

• The Korean Journal of Ecology
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• 제21권2호
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• pp.169-174
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• 1998

This is the review of vegetational history of the post-glacial period in Korea. most of studies for vegetational changes are located in the lowland alluvial plain, especially below the hilly zone of western and eastern coastal regions of Korea. A couple of methods, pollen analysis and radiocarbon dating, have been employed in these studies. These results lead us to establish the pollen zonation in Korea as the followings. Yasuda et al.(1980) classified six period in Yongrang lake of sokcho. These are as follow I. 17,000-15,000yr B.P.: Picea, Abies, Pinus(Haploxylon), Larix stage, II.15,000-10,000yr B.P:Herb, Pteridophyta stage, III.10.000-6,700yr BP.:Quercus stage, IV.6,700-4,500yr B.P.:Pinus, Quercus, Carpinus stage, V.4,500-1,400yr B.P.:Quercus. Pinus stage, VI.1,400yr B.P.-present: Pinus, Herbs stage. Jo(1979) also divided the period into two stages from the outcomes of analysis done in Jumoonjin and other sites I.10,000-6,000yr B.P.:Quercus stage, II.6,000-present: Pinus-Quercus stage, and three substages: IIa.6,000-3,400 yr B.P.:lower Pinus stage, IIb.3,400-2,000yr B.P.:Pinus-Quercus stage, IIc.2,000-present: Pinus stage. Choi(1993, 1996) divided the period into three stages: I.6,000-5,000yr B.P.:Alnus, Quercus stage, II.5,000-4,000yr B.P.: Alnus, Quercus, Pinus stage, III.4,500-2,600yr B.P.: Alnus, Pinus stage. In the period around 6,000yr B.P. distinct dominant species clearly occupied the lowland of the eastern and western coasts. Thus, this strongly supports the fact that even if Korea experienced its warm and wet climate after the lateglacial, it underwent a different environmental change, dry climate, compared to the regions of Japan.