• 청정기술
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• 제24권4호
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• pp.307-314
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• 2018

본 연구에서는 NMO (Natural Manganese Ore), $MnO_2$, $Mn_2O_3$ 촉매를 산소 존재 하에 저온에서 $NH_3$를 환원제로 이용하여 질소산화물(NOx)을 제거하는 선택적 촉매 환원법에 사용되었다. NMO의 경우, 안정성 실험에서 질소산화물 전환율이 423 K에서 100시간 후에도 변하지 않는 것을 확인하였다. 동력학 실험의 경우, 열 및 물질전달이 영향을 주지 않는 영역에서 수행하였다. 정상상태에서의 반응속도 연구는 저온 SCR반응에서 암모니아에 대하여 0차이고 일산화질소에 대해서는 0.41 ~ 0.57차였으며 산소에 대해서는 0.13 ~ 0.26차인 것을 확인하였다. 온도가 증가할 때, 암모니아와 산소 농도의 결과에 따라 반응차수가 감소함을 확인하였다. 촉매 표면에 해리흡착 된 암모니아와 가스상 일산화질소(E-R 모델)와의 반응 및 흡착 된 일산화질소(L-H 모델)와의 반응을 확인하였다.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1008-1017
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• 2021

This study was conducted to investigate the effect of different fattening periods on the growth performance, carcass characteristics, and economic traits of Holstein steers. Sixty Holstein steers (8.0 ± 0.28 months old) with an average body weight (BW) of 231.88 ± 2.61 kg, were randomly allocated to five different fattening period treatments: 20, 21, 22, 23, and 24 months (n = 12 in each treatment group). Final BW and average daily gain (ADG) did not differ among the treatment groups during the early fattening period. At the late stage of the fattening period, the final BW of steers in the 24-month treatment group (812.84 kg) was greater (p < 0.05) than that of steers in the 20-month treatment group (750.39 kg). During the same period, steers in the 20- and 21-month treatment groups had a significantly higher (p < 0.05) ADG than those in the 22-month treatment group. The highest ADG (1.36 kg/day) was found in the 20-month treatment group (1.36), followed by the 21- (1.33 kg/day), 22- (1.22 kg/day), 23- (1.21 kg/day), and 24- (1.14 kg/day) month treatment groups. The feed conversion ratio (FCR) increased as the fattening period increased, and the FCR was 12.88% lower in the 20-month treatment group than in the 24-month treatment group. However, no significant differences were detected in back-fat thickness, loin area, marbling score, and chemical characteristics (water, crude protein, and crude fat content) among the treatment groups. The composition of fatty acids including C18:0, C18:1, saturated fatty acids, unsaturated fatty acids, and poly-unsaturated fatty acids did not differ among the experimental groups. As the fattening period increased, production costs increased, resulting in a decrease in gross income. The gross income for steers in the 24-month treatment group was 35.8% and 23.5% lower than that for steers in the 20- and 21-month treatment groups, respectively. Taken together, the best performance, including the ADG, FCR, and gross income, was obtained when the fattening program of the Holstein steers lasted 20 months.

• 한국가금학회지
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• 제49권3호
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• pp.139-144
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• 2022

본 연구는 육계 병아리 시기에 세 가지의 점등시간이 성장 능력, 혈액 생화학 성상 및 스트레스 지표에 미치는 영향을 조사하기 위해 수행되었다. 공시동물은 1일령 Ross 308 육계(57.0±0.12 g) 수컷 252수를 7일 동안 사육하였으며, 처리구는 점등3처리구(24 L, 22 L/2D, 18 L/6D)로 나누고, 처리당 4반복, 반복당 22수를 완전임의 배치하였다. 광원은 LED 전구를 사용하였으며, 기본 조도는 30 lx를 제공하였다. 시험사료는 옥수수-대두박 위주의 시판 사료(ME 3,150 kcal/kg, CP 22.0%)를 이용하였으며, 사료와 물은 자유롭게 섭취하도록 하였다. 점등시간에 따른 체중, 증체량, 사료요구율 및 간 무게 비율은 18 L/6D과24 L 처리구에서 유의적인 차이를 보였으나(P<0.05), 22 L/2D 처리구는 24 L 처리구 및 18 L/6D 처리구간 유의차를 보이지 않았다. 가슴근육의 무게 비율은 18 L/6D 처리구에서 5.59%로 다른 처리구에 비해 낮게 나타났다(P<0.05). 혈청 생화학 성분 중 TG는 점등시간이 줄어들수록 유의적으로 증가하였으나(P<0.05), ALT는 24 L 처리구에 비해 22 L/2D 처리구에서 유의적으로 높았다(P<0.05). 혈청 내 cytokine(IL-6, TNF-α) 함량은 처리구 사이에서 유의적인 차이를 보이지 않았으나, corticosterone 함량은 24 L 처리구가 18 L/6D 처리구에 비해 유의적으로 높은 값을 나타내었다(P<0.05). 결론적으로, 육계 병아리 시기에는 성장 능력과 동물복지를 모두 고려하였을 때 22시간 점등이 적당하다고 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권7호
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• pp.1001-1006
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• 2011

To determine the efficiency of copper (Cu) supplementation, a feeding experiment was carried out with 240 day old broiler chicks (vencobb-100). Birds were divided into four dietary treatments: i) C - no additives, ii) $T_1$-75 mg inclusion of Cu/kg diet, iii) $T_2$-150 mg inclusion of Cu/kg diet, iv) $T_3$-250 mg inclusion of Cu/kg diet. The present study was carried out in the Department of Animal Physiology, West Bengal University of Animal and Fishery Sciences, Kolkata, India for a period of 42 days (6 weeks). Growth performance was measured in terms of live weight gain, cumulative feed intake and feed conversion ratio at the end of $21^{st}$ and $42^{nd}$ day of the experiment and the result was found to be encouraging for commercial enterprises when the chickens were fed at 150 mg Cu/kg ($T_2$) of their diet. Excess dietary copper more than 150 mg/kg reduced the haemoglobin (Hb) concentration in blood and resulted in the accumulation of copper in the liver with decreased blood Hb concentration and packed cell volumes (PCV). Copper supplementation increased the total erythrocyte count (TEC) as copper is involved in erythropoiesis. But, from the result it is indicated that the dietary copper concentration could not alter the total leukocyte count (TLC). In case of different leucocytes count (DLC), there were no significant differences observed among the different treated groups. Statistical analysis showed significant (p<0.01) difference in plasma concentration of copper, zinc, ferrous and cholesterol among the different copper treated groups. The result indicates that supplementation of copper is an effective way of improving the production performance and haematological parameters in broiler chicken.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1274-1279
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• 2003

Thirty-six Naeimi ram lambs were equally and randomly allotted to four treatment groups with three replications per treatment to determine the simple and additive effects of monensin and zeranol on growth performance, carcass characteristics and nutrient digestibility. The treatment groups were: basal diet-fed lambs (C), monensin-fed lambs (M) where the basal diet was supplemented with 33 mg monensin per kilogram DM, lambs implanted with 12 mg zeranol (Z), and monensin-fed lambs implanted with zeranol (MZ). Lambs fed monensin-containing diet consumed 10.5% less (p<0.05) DM/100 kg weight and were 8.3% more (p<0.05) efficient in converting feed than lambs fed control diet. Zeranol implanted lambs tended to grow 35.2% (p<0.05) faster, consumed 5.1% more (p<0.05) feed and were (p<0.05) 21.9% more efficient in their feed conversion than control lambs. Responses of lambs to monensin and zeranol implants were not additive. Except for Z treatment, there were no marked differences in all carcass characteristics among the various treatment groups. Z-lambs produced 12.7% heavier (p<0.05) carcasses compared with those from C treatment. Also fat parameters, namely, kidney and pelvic fat (KP), body wall thickness and fat thickness, indicated trends for higher finish in Z treatment lambs (p<0.05) than for those lambs from other treatments. Except for CF and ADF, no significant differences in nutrients digestibility were noticed between various treatments; feeding monensin resulted in 24.5% and 8.5% depressions (p<0.05) in CF and ADF digestibility, respectively in comparison to C treatment. Nitrogen retention as percentage of total N-intakes was averaging 7.5 and 20.2% higher (p<0.05) in lambs implanted with zeranol than those fed the M and C diets, respectively.

• 천문학회지
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• 제31권2호
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• pp.161-171
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• 1998

We have mapped about 1.5 square degree regions of Lynds 1299, a well isolated dark cloud in the Outer Galaxy (l = $122^{\circ}$, b = $-7^{\circ}$), in the J = 1- 0 transition of $^{12}CO$ and $^{13}CO$ with the 13.7 m radio telescope at Taeduk Radio Astronomy Observatory (TRAO). We found that there are two velocity components in the molecular emission, at $V_{LSR} = -52 km S^{-1}$ (Cloud A) and -8.8 km $s^{-1}$ (Cloud B), respectively. We have derived physical parameters of two molecular clouds and discussed three different mass estimate techniques. We found that there are large discrepancies between the virial and LTE mass estimates for both clouds. The large virial mass estimate reflects the fact that both are not gravitationally bound. We adopt the mass of $5.6 {\times}10^3 \;M{\bigodot}$ for Cloud A and $1.2{\times}10^3 \;M{\bigodot}$) for Cloud B using conversion factor. Cloud A is found to be associated with a localized star forming site, and its morphology is well matching with that of far-infrared (FIR) dust emission. It shows a clear ring structure with an obvious velocity gradient. We suggest that it may be a remnant cloud from a past episode of massive star formation. Cloud B is found to be unrelated to Cloud A (d = 800 pc) and has no specific velocity structure. The average dust color temperature of the uncontaminated portion of Cloud A is estimated to be 24$\~$27.4 K. The low dust temperature may imply that there is no additional internal heating source within the cloud. The heating of the cloud is probably dominated by the interstellar radiation field except the region directly associated with the new-born B5 star. Overall, the dust properties of Cloud A are similar to those of normal dark cloud even though it does have star forming activity.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.914-922
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• 1999

An experiment was conducted to determine the effects of dietary energy and protein on performance and carcass composition of broilers under heat stress during the growing period (3-6 weeks). A factorial arrangement of three levels of energy (3.0, 3.2 and 3.4 kcal/g), three levels of protein (18, 20 and 22%), an two rearing temperatures were used in this study. Groups of birds were kept under moderate temperature ($24{\pm}1^{\circ}C/24h$) or hot cycling temperature ($26-34^{\circ}C/6h$, $34{\pm}1^{\circ}C/12h$, and $34-26^{\circ}C/6h$). Body weight (BW), weight gain (WG), feed intake (FI), feed conversion (feed : gain) (FC), carcass weight (CW), carcass yield (YP), breast meat (BM), abdominal fat (AF), drumsticks (DS), and thighs (TH) percentages were determined at the end of the experiment. Hot cycling temperature significantly (p<0.05) decreased BW, WG, FI, CW, and BM, increased FC, YP, DS, and TH but did not affect AF. High energy significantly (p<0.05) increased BW, WG, CW, YP, AF, and TH, decreased FI and FC but did not affect BM or DS. This improvement was observed only under moderate temperature resulting in significant (p<0.05) energy by temperature interaction. High protein significantly (p<0.05) increased BW, WG, CW and BM, decreased AF but did not affect FI, FC, TP, DS, or TH. There were no significant protein by temperature interactions for any of the parameters tested except CW. It is concluded, under the conditions imposed in this experiment, that increasing dietary energy did not alleviate the depressing effect of heat stress while increasing dietary protein up to 22% improved the performance of broilers irrespective of rearing temperature.

• Journal of Gastric Cancer
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• 제12권3호
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• pp.173-178
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• 2012

Purpose: To report the initial clinical experience with single-incision laparoscopic gastric wedge resection for submucosal tumors. Materials and Methods: The medical records of 10 patients who underwent single-incision laparoscopic gastric wedge resection between July 2009 and March 2011 were reviewed retrospectively. The demographic data, clinicopathologic and surgical outcomes were assessed. Results: The mean tumor size was 2.5 cm (range, 1.2~5.0 cm), and the tumors were mostly located on the anterior wall (4/10) or along the greater curvature (4/10), of the stomach. Nine of ten procedures were performed successfully, without the use of additional trocars, or conversion to laparotomy. One patient underwent conversion to multiport laparoscopic surgery, to get simultaneous cholecystectomy safely. The mean operating time was 66.5 minutes (range, 24~132 minutes), and the mean postoperative hospital stay was 5 days (range, 4~7 days). No serious perioperative complications were observed. Of the 10 submucosal tumors, the final pathologic report revealed 5 gastrointestinal stromal tumors, 4 schwannomas, and 1 heterotopic pancreas. Conclusions: Single-incision laparoscopic gastric wedge resection for gastric submucosal tumors is feasible and safe, when performed by experienced laparoscopic surgeons. This technique provides favorable cosmetic results, and also short hospital stay and low morbidity, in carefully selected candidates.

• 폴리머
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• 제24권4호
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• pp.520-528
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• 2000

본 연구는 고형분 70%인 하이솔리드 아크릴 수지 (BMHA)를 합성하여, 환경친화성 도료인 하이솔리드 아크릴/폴리이소시아네이트 도료(BNHS)에 적용하고 그의 도막특성을 살펴본 것에 그 의의가 있다. BMHA는 새로운 형의 단량체로서 acetoacetoxyethyl methacrylate (AAEM)을 도입하고 여기에 n-butyl acrylate, methyl methacrylate 및 2-hydroxyethyl acrylate를 4원공중합시켜 얻었다. BMHA 합성에 있어서 T$_{g}$ 값이 낮을수록, AAEM의 양이 많을수록 각각 높은 전환율을 나타내었고, T$_{g}$값 고정하의 OH 값 변화에 따른 전환율은 큰 차이가 없었다. BMHA와 폴리이소시아네이트를 상온경화시켜 하이솔리드 BNHS 도료를 제조하고서 자동차 상도용 도료로서의 적합성 여부를 알아보기 위하여 도막물성 시험을 한 결과, BNHS내에 AAEM 도입 전후의 도막물성 비교시험에서 AAEM 도입후에 내마모성과 내용제성이 향상됨으로써 자동차 상도용 도료로서의 응용가능성을 보여주었다.다.

• Restorative Dentistry and Endodontics
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• 제41권4호
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• pp.271-277
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• 2016

Objectives: In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs) on the degree of conversion (DC) and the mechanical properties of resin cements. Materials and Methods: Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG), according to the different radiant exposures (5, 10, and $20J/cm^2$) and two LCUs (single-peak and polywave). The specimens were made (7 mm in length ${\times}$ 2 mm in width ${\times}$ 1 mm in height) using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E) by a three-point bending test. Data were assessed for normality, after which two-way analysis of variance (ANOVA) and post hoc Tukey's test were performed. Results: No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions: On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was material-dependent.