• 콘크리트학회논문집
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• 제28권6호
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• pp.647-653
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• 2016

본 연구에서는 FA (Fly Ash)를 20%치환한 배합에 대하여 TDFA (Tire Derived Fuel Ash)를 3.0~12.0%까지 중량 치환하면서 내구성 평가를 수행하였다. TDFA는 열병합발전소에서 열효율을 높이기 위해 폐타이어를 혼소시킨 뒤 발생한 산업부산물로서 국내에서 콘크리트에 적용한 연구는 없는 상태이다. 이를 위해 물-결합재를 50%, FA를 20% 치환한 Control 콘크리트를 제조하였으며, TDFA를 치환하면서 압축강도, 촉진 탄산화 시험, 촉진염해 시험, 공극구조평가를 수행하였다. 압축강도, 탄산화, 공극구조에서는 12%까지 TDFA를 FA와 치환해도 동등이상의 성능을 확보하였다. 특히 염해에 대해서는 TDFA의 치환률의 증가에 따라 뚜렷한 염화물 확산계수의 감소를 나타내어 최종적으로 75.3~70.9%까지 염화물 확산계수가 감소하였다. TDFA를 혼입한 콘크리트 배합시, 워커빌리티의 확보가 가능하다면 TDFA를 혼입한 콘크리트는 내구성 개선에 효과적일 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권5호
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• pp.690-700
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• 2012

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen ($NH_3$-N) and $H_2S$ gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, $NH_3$-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as $NO_2$, $NO_3$ and $SO_4$ concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that $NH_3$-N, $H_2S$ and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

• 동아시아식생활학회지
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• 제16권6호
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• pp.717-723
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• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• 한국전자파학회논문지
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• 제18권7호
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• pp.839-846
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• 2007

본 논문에서는 새로운 구조의 이중 대역 feedforward 선형 전력 증폭기(FFW LPA)의 설계 방법을 제안하였다. 현재까지 이중 대역 FFW LPA 설계의 기술적인 어려움은 단일 대역 FFW LPA에서 사용되는 신호 상쇄기를 이중 대역 동작으로 확장시키기가 쉽지 않았다는 점이다. 따라서 본 논문에서는 이중 대역 동일 군속도 지연 주 신호 상쇄기와 혼변조 왜곡 신호(Intermodulation Distortion: IMD) 상쇄기의 설계 방법, 그리고 이를 이용하여 단일 대역 FFW 기법을 확장한 이중 대역 FFW LPA의 설계 방법을 제안하였다. 제안하는 설계 방식의 효용성을 검증하기 위하여, 동작 대역의 중심 주파수를 기준으로 1.26 GHz 이격된 디지털 셀룰러 대역($f_0=880$ MHz)과 IMT-2000($f_0=2.14$ GHz) 대역 기지국용 이중 대역 feedforward 선형화 시스템을 구현하였다. 각 대역별로 CDMA IS-95A 4FA 신호와 WCDMA 4FA 신호를 인가하여 인접 채널 누설비(Adjacent Channel Leakage Ratio: ACLR)의 개선 정도를 측정한 결과, 디지털 셀룰러 대역에서 평균 출력 전력 41.5 dBm일 때 16.52 dB, IMT-2000 대역에서 평균 출력 전력 40 dBm일 때 18.59 dB의 개선 효과를 동시에 얻을 수 있었다.

• 한국구조물진단유지관리공학회 논문집
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• 제20권5호
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• pp.1-8
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• 2016

본 연구에서는 산업부산물인 TDFA를 혼입한 콘크리트에 대하여 초기재령의 공학적 특성을 분석하였다. 물-결합재비 0.5, FA 치환율 20%인 콘크리트를 대상으로 TDFA를 3~12%치환하여 경화 전 및 경화 후의 특성을 분석하였다. TDFA 혼입율 6% 이후의 배합에서는 작업성이 현저하게 감소하였고 공기량 확보가 어려웠으며, 이로 인해 감수제 및 공기연행제를 추가하여 작업성을 개선시켰다. TDFA 혼입율 6~12%까지는 콘크리트의 강도에 큰 영향은 없었으며, 탄산화저항성 및 염해저항성에서는 FA 20% 치환 배합보다 우수한 성능을 나타내었다. 그러나 공기량이 부족한 TDFA 혼입율 6%배합에서는 동결융해 저항성이 크게 감소하였다. 공기량 및 작업성이 확보된다면 FA를 12%수준까지 TDFA로 치환해도 공학적인 성능을 확보할 수 있을 것으로 판단된다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.120-120
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• 1995

The total size of the pF AR1, a genomic clone of Frankia FaCI, was estimated to be about 44Kb by summation of the individual fragment length generated by single or double restriction enzymes. Southern hybridization analyses with Azotobacter vinelandii nif-genes as probes and partial sequencing analyses of the subclones revealed that organization of the nif-gene in the FaCI strain was nifV, H, D, K, E, N, X, W, B. The organization of the structural genes for nitrogenase is the same in this Frankia strain as it is in most other nitrogen-fixing prokaryotes but the positioning of the nifV-like gene relative to the nifHDK cluster differs. A consensus nif-promoter-like sequence, found at 5' of nifH, was not detected upstream of the niJV-like gene. nifV-like gene contained a ORF of 1206 NT encoding 401 amino acids. The nucleotide sequence and deduced amino acid sequence of the gene exhibit homology value of 65% and 41% with that from A vinelandii, respectively. The putative Shine-Dargamo sequences were present preceding nitK, nifH, D, K, and nifE, and in nitK gene putative start codon GTG was detected instead of A TG. The nucleotide and amino acid sequence of niIK of FaCI showed 82% and 76% homolgy with those of Frankia HFPCc 13, respectively. Amino acid sequence of niIK showed 69% and 61% homology with those of A vinelandii, Klebsiella pnewnoniae, respectively, while that of nifE 73% and 71%, respecti vely.i vely.

• 한국건설순환자원학회논문집
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• 제12권2호
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• pp.152-161
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• 2024

본 논문에서는 마그네시아-인산칼륨 기반의 무시멘트 하이볼륨 플라이애시 보수 모르타르를 제조하고 그 기초 품질 특성을 평가하였다. 최적의 무시멘트 모르타르 배합을 도출하기 위하여, 마그네시아 비율을 기준으로 제조 특성을 평가하였고, 플라이애시 혼합에 따른 모르타르 제조 특성을 평가하였다. 또한 마그네시아 무시멘트 보수 모르타르는 플라이애시 혼합의 효과 및 바잘트 섬유를 고려하여 제조하였다. 평가결과를 통하여, 마그네시아 무시멘트 보수 모르타르의 최적 배합을 결정하였으며, 작업성 및 기초 품질 특성 평가를 통하여 실현 가능성을 검토하였다. 본 논문에서는 마그네시아의 최적 비율은 P:M 1:0.5, W/B 30 %로 나타났으며, FA와 바잘트 섬유 혼합 시 섬유 분산성과 워커빌리티가 향상됨을 확인하였다. 또한 FA를 50 % 이상 혼합해도 6시간 이내 목표 강도를 만족하는 것으로 나타났으며, 플로우가 최대 18 % 증가하고, 휨강도는 1~2 MPa 수준 감소하였다.

• 한국환경농학회지
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• 제17권2호
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• pp.164-169
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• 1998

토양반응이 산성이고 붕소함량이 낮은 사양질 밭에서 토양개량제로 석탄회와 석고, 패각을 석탄회 80, 패각4, 석탄회56+석고24, 석탄회40+석고24+패각0.8ton/ha 사용하고 가을 노지배추를 재배하여, 이들의 토양개량 및 작물증수 효과를 검토하였다. 전반적으로 석탄회, 석고, 패각 시용은 토양화학성을 개선시켰으며 배추 수량과 엽중 N, P, K, Ca, B 함량을 증대시켰다. 개량제중 석탄회를 단용한 구에서는 토양의 산도중화능이 우수하였고 유효인산 및 붕소의 증가와 철의 감소가 가장 뚜렷하였다. 석탄회+석고+패각의 혼용구에서는 칼슘, 마그네슘, 붕소의 증가가 뚜렷하였다. 그리고 석탄회가 시용된 구에서는 개량제 무시용구 및 패각단 용구와 달리 붕소결핍 없이 증수된 경향이었다. 처리별 증수효과는 대조구 수량 78.2ton/ha을 기준으로 석탄회+석고+패각 혼용구에서 85%, 석탄회+석고 혼용구에서 77%, 석탄회 단용구에서 66%, 패각 단용구에서 5%였다. 수확된 배추내에 N, B, 환원당, 비타민-C 함량은 처리별 성적 수량과 일치하였고 조섬유 함량은 그 반대 경향이었다.

• 한국환경과학회지
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• 제16권8호
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• pp.865-872
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• 2007

The waterborne perfluoroacylic polyurethane composite (WFPUC) series were prepared by the emulsion polymerization (WFPUC-E) and the physical blending (WFPUC-B). WFPUC-E was prepared by polymerizing perfluoroalkyl ethyl acrylate (FA) and waterborne polyurethane (WPU), and WFPUC-B was prepared by blending FA copolymer and WPU. The structures of the synthesized WFPUC were identified by using FT-IR-ATR. The surface and thermal properties of the synthesized WFPUC were investigated by measuring contact angle, surface energy, and TGA. The surface energy of WFPUC-E was lower than that of WFPUC-B. The thermal stability of the WFPUC-B showed better than that of the WFPUC-E.

• Nutrition Research and Practice
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• 제10권5호
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• pp.477-486
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• 2016

BACKGROUND/OBJECTIVES: Consumption of pine nut oil (PNO) was shown to reduce weight gain and attenuate hepatic steatosis in mice fed a high-fat diet (HFD). The aim of this study was to examine the effects of PNO on both intestinal and hepatic lipid metabolism in mice fed control or HFD. MATERIALS/METHODS: Five-week-old C57BL/6 mice were fed control diets containing 10% energy fat from either Soybean Oil (SBO) or PNO, or HFD containing 15% energy fat from lard and 30% energy fat from SBO or PNO for 12 weeks. Expression of genes related to intestinal fatty acid (FA) uptake and channeling (Cd36, Fatp4, Acsl5, Acbp), intestinal chylomicron synthesis (Mtp, ApoB48, ApoA4), hepatic lipid uptake and channeling (Lrp1, Fatp5, Acsl1, Acbp), hepatic triacylglycerol (TAG) lipolysis and FA oxidation (Atgl, Cpt1a, Acadl, Ehhadh, Acaa1), as well as very low-density lipoprotein (VLDL) assembly (ApoB100) were determined by real-time PCR. RESULTS: In intestine, significantly lower Cd36 mRNA expression (P<0.05) and a tendency of lower ApoA4 mRNA levels (P = 0.07) was observed in PNO-fed mice, indicating that PNO consumption may decrease intestinal FA uptake and chylomicron assembly. PNO consumption tended to result in higher hepatic mRNA levels of Atgl (P = 0.08) and Cpt1a (P = 0.05). Significantly higher hepatic mRNA levels of Acadl and ApoB100 were detected in mice fed PNO diet (P<0.05). These results suggest that PNO could increase hepatic TAG metabolism; mitochondrial fatty acid oxidation and VLDL assembly. CONCLUSIONS: PNO replacement in the diet might function in prevention of excessive lipid uptake by intestine and improve hepatic lipid metabolism in both control diet and HFD fed mice.