• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1171-1176
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• 2003

The effects of dietary conjugated linoleic acid (CLA) on lipid concentrations and fatty acid composition of various tissues were studied in young chicks. From 7 days of age, a total of 160 chicks were divided into 4 groups, placed into 4 pens per group (10 birds per pen) and fed one of four experimental diets containing 6% tallow (TO 6%), 4% tallow plus 2% CLA (TO 4%-CLA 2%), 2% tallow plus 4% CLA (TO 2%-CLA 4%) or 6% CLA (CLA 6%) for 3 weeks. There were no significant differences in growth performances and the relative weights of various organs, but relative liver weight of chicks fed dietary CLA at 4 and 6% levels was significantly higher (p<0.05) than that of TO 6% group. The chemical compositions of leg muscle were not affected by CLA feeding. However, hepatic total lipid of chicks fed 6% CLA diet was significantly higher (p<0.05) than those of TO 6% and TO 4%-CLA 2% groups. The concentrations of various lipid fractions in serum were not affected by CLA feeding. With the increase in dietary CLA levels, cis 9-trans 11 CLA, trans 10-cis 12 CLA and total CLA of leg muscle increased linearly. The relative proportions of C18:1 $\omega$ -9 and C20:4 $\omega$-6 fatty acids in the leg muscles of chicks fed the CLA containing diets were significantly lower (p<0.05) than those of TO 6% group. These results indicate that the levels of CLA isomers were increased linearly in dose-dependent manner after feeding of synthetic CLA source. But it was also observed that excessive amount of dietary CLA resulted in the possible adversely effects, such as increase of liver weight, hepatic lipid accumulation and serum GOT level.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.174-179
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• 2013

This paper presents a capacitor loaded tunable bandpass chip filter using multiple split ring resonators (MSRRs) with two transmission zeros. To obtain high selectivity and minimize the chip size, asymmetric feed lines are adopted to make a pair of transmission zeros located on each side of passband. Compared with conventional filters using cross-coupling or source-load coupling techniques, the proposed filter uses only two resonators to achieve high selectivity through a pair of transmission zeros. In order to optimize selectivity and sensitivity (insertion loss) of the filter, the effect of the position of asymmetric feed line on transmission zeros and insertion loss is analyzed. The SOI-CMOS switched capacitor composed of metal-insulator-metal (MIM) capacitor and stacked-FETs is loaded at outer rings of MSRRs to tune passband frequency and handle high power signal up to +30 dBm. By turning on or off the gate of the transistors, the passband frequency can be shifted from 4GH to 5GHz. The proposed on-chip filter is implemented in 0.18-${\mu}m$ SOI CMOS technology that makes it possible to integrate high-Q passive devices and stacked-FETs. The designed filter shows miniaturized size of only $4mm{\times}2mm$ (i.e., $0.177{\lambda}g{\times}0.088{\lambda}g$), where ${\lambda}g$ denotes the guided wave length of the $50{\Omega}$ microstrip line at center frequency. The measured insertion loss (S21)is about 5.1dB and 6.9dB at 5.4GHz and 4.5GHz, respectively. The designed filter shows out-of-band rejection greater than 20dB at 500MHz offset from center frequency.

• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1129-1136
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• 1999

TIN films were prepared on Si(100) substrate by ICP-CVD(inductive1y coupled plasma enhanced chemical vapor deposition) using TEMAT(tetrakis ethylmethamido titanium : Ti$[\textrm{N}\textrm{(CH)}_{3}\textrm{C}_{2}\textrm{H}_{5}]_{4}$) precursor at various deposition conditions. Phase, microstructure, and the electrical properties of TIN films were characterized by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM) and electrical measurements. Polycrystalline TiN films with B1 structure were grown at temperatures over $200^{\circ}C$. Preferentially oriented along TiN(111) films were obtained at temperatures over $300^{\circ}C$ with the flow rates of 10, 5, and 5 sccm for TEMAT, $\textrm{N}_{2}$ and Ar gas. The TiN/Si(100) interface was flat and no chemical reaction between TIN and $\textrm{SiO}_2$ was found. The resistivity, carrier concentration and the carrier mobility for the TiN sample prepared at $500^{\circ}C$ are 21 $\mu\Omega$cm, 9.5$\times\textrm{10}^{18}\textrm{cm}^{-3}$ and $462.6\textrm{cm}^{2}$/Vs, respectively.

• ALGAE
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• v.35 no.1
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• pp.91-106
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• 2020

Incorporating renewable fuel into practice, especially from algae, is a promising approach in reducing fossil fuel dependency. Algae are an exceptional feedstock since they produce abundant biomass and oils in short timeframes. Algae also produce high-valued lipid products suitable for human nutrition and supplement. Achieving goals of producing algae fuels and high-valued lipids at competitive prices involves further improvement of technology, especially better control over cultivation. Manipulating microalgae cultivation conditions to prevent contamination is essential in addition to promoting optimal growth and lipid yields. Contamination of algal cultures is a major impediment to algae cultivation that can however be mitigated by choosing extremophile microalgae. This work describes the isolation of alkali-tolerant / alkaliphilic microalgae native to South Florida with ideal characteristics for cultivation. For that purpose, water samples from Lake Okeechobee were inoculated into Zarrouk's medium (pH 9-12) and incubated for 35 days. Selection resulted in isolation of three strains that were screened for biomass and lipid accumulation. Two alkali-tolerant algae Chloroidium sp. 154-1 and Chlorella sp. 154-2 were poor lipid accumulators. One of the isolates, the diatom Fistulifera sp. 154-3, was identified as a lipid accumulating, alkaliphilic organism capable of producing 0.233 g L^-1 d^-1 dry biomass and a lipid content of 20-30% dry weight. Lipid analysis indicated the most abundant fatty acid within Fistulifera sp. was palmitoleic acid (52%), or omega-7, followed by palmitic acid (17%), and then eicosapentanoic acid (15%). 18S rRNA phylogenetic analysis formed a well-supported clade with Fistulifera species.

• Korean Journal of Environment and Ecology
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• v.13 no.4
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• pp.340-347
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• 2000

지리산국립공원의 쌍계사지의 불일폭포-성불재 계곡부(해발 600-1.1200m)의 해발고와 사면부위에 따른 교목층의 산림구조를 조사하기 위하여 해발고와 사면부위에 따라 42개 조사구를 설정하였다 교목상층의 밀도 평균흉고직경 흉고단면적의 범위는 각각 545-1,700본/ha 11.0-23.5cm, 19.1-27.8m2/ha 이었다 교목상층의 평균흉고직경과 흉고단면적 교목층 전체의 흉고단면적은 계곡중부에서 가장컸다 해발고가 높아짐에 따라 중요치가 증가하는 경향을 보이는 수종은 신갈나무 소나무 등이었으며 감소하는 수종은 굴참나무 졸참나무, 비목나무 등이었다 사면하부에서 상부로 갈수록 중요치가 증가하는 수종은 굴참나무 쇠물푸레 철쭉꽃 등이었으며 감소하는 수종은 노각나무 비목나무 느티나무 당단풍 때죽나무 등이었다 해발고와 사면부위가 높을수록 종수와 종다양도는 감소하였으며 해발고대별 종다양도는 0.626-1.320 의범위를 보였다 계곡정부를 제외한 해발고대간 유사도지수는 36.1-60.6% 사면부위간 유사도지수는 59.2-74.4% 로서 사면부위보다 해발고에 따른 종구성 상태의 차이가 심한 것으로 나타났다 수종별 중요치에 의한 Cluster 분석결과 계곡하부의에 위치한 서어나무-활엽수군집 계곡상부의 사면중 하부에 위치한 신갈나무-활엽수군집 계곡정부와 계곡상부의 사면상부에 위치한 신갈나무-소나무군집 등 4개 유형군집으로 구분되었다 종상관 분석결과 소나무 신갈나무 쇠물푸레 철쭉꽃 등 4개 수종간 비목나무 산뽕나무 생강나무 등 3개 수종간에는 유의적인 정의 상관이 있었다. 신갈나무, 쇠물푸레 철쭉꽃 등은 졸참나무와 소나무 쇠물푸레 등은 비목나무 서어나무와 유의적인 부의 상관이 있었다.증가에 따라 250 g/L까 지 증가하여 최대 51.0%의 수율과 0.63 g/L-h의 생산성을 나타내었다. 얻을 수 있었다. 따라서 이 방법이 일단 생산성 향상을 위한 세포의 고농도 배양에는 조사한 여러 배양 시스템 중에 가장 효율적인 시스템임올 알 수 있었다 하지만 이 시스템 에서 포도당을 낮은 level로 유지할 수 있었으나, 초산의 과도한 축적으로 항체 생산성의 향상은 예상에 비해 크지 않았다. 81%), C18 0(12.38%), C18: 1(25.93%), C22:6(9.95%)이며 결합지방질(結合脂肪質)은 C14 : 0(11.60%), C16 : 0(18.94%), C16: 1(10.42%). C18 : 1(10.89%), C22 : 6(23.44%)이었다. 총필수지방산(總必須脂肪酸) 함량(含量)은 극성지방질(極成脂肪質)$(20.14{\sim}31.12%)$이 비극성지방질(非極成脂肪質)$(6.97{\sim}11.13%)$보다 훨씬 높았고, 결합지방질(結合脂肪質)이 유리지방질(遊離脂肪質)보다 높았으며 부위별(部位別)로는 피부(皮部)$(15.18{\sim}15.41%)$가 육질부(肉質部)$(6.97{\sim}11.13%)$보다 높았다. 또${\omega}3$고도부포화지방산(高度不飽和脂肪酸) 함량(含量)은 육질부(肉質部)$(15.15{\sim}28.32%)$가 피부(皮部)$(6.77{\sim}18.18%)$나 내장부(內臟部)$(8.35{\sim}9.74%)$보다 높았으며, 육질부(肉質部)에서는 극성지방질(極成脂肪質)

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.42-47
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• 1986

The fatty acid composition of lipids extracted from 18 kinds of salted and fermented sea foods which have been consumed in Korea were examined. The lipid contents of salted and fermented sea foods showed wide difference (0.8-11.9%) depending on species and portions of raw materials. In fatty acid composition of salted and fermented sea foods prepared with whole fishes, the saturated fatty acid was the most predominant component, and the major fatty acids were 16:0, 18:1, 22:6, 16:1 and 20:5. In case of salted and fermented products prepared with gills, roe or intestines, the polyenoic fatty acid was the main component, the major fatty acids were 18:1, 16:0, 22:6, 20:5, 16:1 and 18:3. In these products the composition ratios of 20:5 and 18:3 were higher, and that of 16:0 and 16:1 were slightly lower as compared with salted and fermented whole fish products. And in case of salted and fermented crustacea and mollusk, the polyenoic fatty acids such a 22:6 and 20:5 were the most predominant component, the abundant fatty acids were 22:6, 16:0, 20:5, 18:1 and 16:1. Judging from results, salted and fermented sea foods were abundant of the highly unsaturated fatty acids such as 20:5, 22:6 inspite of the long fermentation periods.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.56-59
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• 1991

The polyervstalline $Cu_{0.28}Ag_{0.72}InSe_{4.4}S_{0.6}$ thin films are prepared by vacuum heat treatment of laver, which is deposited by direct resisting vacuum evaporation. From optical absorption spetra, the optical hand gap energy is determined to be 1.5[eV] at room temerature. From electrical method. hole concentration, resistivity and mobility are 9.3*$10^{18}$[$cm^{-3}$], 6*$10^{-2}$[$\Omega$$.$cm], 11.2[$\textrm{cm}^2$/V$.$sec] respectively at room temperature.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.12
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• pp.1737-1741
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• 2015

A multi-channel CMOS transimpedance amplifier(TIA) array is realized in a $0.18-{\mu}m$ CMOS technology for the applications of panoramic scan LADAR systems. Each channel consists of a PIN photodiode and a feed-forward TIA that exploits an inverter input stage followed by a feed-forward common-source amplifier so as to achieve lower noise and higher gain than a conventional voltage-mode inverter TIA. Measured results demonstrate that each channel achieves $76-dB{\Omega}$ transimpedance gain, 720-MHz bandwidth, and -20.5-dBm sensitivity for $10^{-9}$ BER. Also, a single channel dissipates the power dissipation of 30 mW from a single 1.8-V supply, and shows less than -33-dB crosstalk between adjacent channels.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.133-138
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• 2008

Fire can affect microbial community structure of soil through altered environmental conditions, nutrient availability, and biotic source for microbial re-colonization. We examined the influence of fire on chemical properties and soil enzyme activities of soil for 10 months. We also characterized the soil microbial community structure through ester-linked fatty acid analysis(EL-FAME). For this study, we established five burned plots(1*1 m) and 5 unburned plots outside the margin of fire. Soil was sampled three soil cores in a each plots and composited for analysis at 1, 3, 5, 8, and 10 month after fire. The fire caused an increase in soil pH, exchangeable Ca, and Mg, organic matter, available $P_2O_5$ compared to unburned sites. The content of $NH_4-N$ in burned site was significantly higher than that of unburned site and this effect continued for 8 months after fire. There was no difference of $NO_3-N$ content in soil between burned and unburned site. Fire caused no change in acid phosphatase and arylsulfatase activities but $\beta$-glucosidase and alkaline phosphatase activities in burned site were increased compared to unburned site. Microbial biomass as estimated by total concentration of EL-FAMEs in burned sites was significantly higher than that of unburned sites at one month after fire. Burned site decreased the EL-FAMEs indicative of gram-positive bacteria and tended to increase the fatty acid associated with gram-negative bacteria at one and three months after fire. The sum of EL-FAME compound $18:2{\omega}6,9c$ and $18:1{\omega}9c$ as served fungal biomarkers was decreased in burned site compared to unburned site.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.522-526
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• 2007

Structural features and electrochemical performances of cokes pyrolized from oxidized cokes were examined, and compared with KOH-activated coke. Needle cokes ($d_{002}=3.5{\AA} $), having a graphene layer structure, were changed to a single phase of graphite oxide after oxidation treatment with an acidic solution having an $NaCLO_3$/needle coke composition ratio of above 7.5, and the inter-layer distance of the oxidized coke was expanded to $6.9{\AA} $ with increasing oxygen content. After heating at $200^{\circ}C$, the oxidized coke was pyrolized to the graphene layer structure with inter-layer distance of $3.6{\AA} $. However, the change of the inter-layer distance of the needle coke was not observed in the KOH activation process. On the other hand, an intercalation of electrolyte ions into the pyrolized coke, observed at first charge, occurred at 1.0 V, in which the value was lower than that of KOH-activation coke. The cell capacitor using pyrolized coke exhibited a lower internal resistance of $0.57{\Omega}$ in 1 kHz, and a larger capacitance per weight and volume of 30.3 F/g and 26.9 F/ml at the two-electrode system in the potential range 0~2.5 V than those of the cell capacitor using KOH-activation of coke. This better electrochemical performance may be associated with structure defects in the graphene layer derived from the process of the inter-layer expansion and shrinkage.