육성돈에서 Phytase 첨가가 Extrusion 한 쌀겨의 P 이용성에 미치는 영향

김영길,김인호,손중천,김은주,권기범,문태현 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.3

본 시험은 육성돈에 있어 extrusion된 쌀겨에 대한 P의 이용성과 extrusion된 쌀겨에 phytase를 첨가하므로서 P의 이용성에 미치는 영향을 구명하고자 영양소 소화 시험을 실시하였다. Extrusion된 쌀겨와 extrusion된 쌀겨에 phytase을 첨가한 구간의 비교는 phytase의 첨가에 의해 건물 소화율이 약간 증가하는 경향을 보였다(P<0.04). N 소화율은 쌀겨구 보다는 extrusion된 쌀겨구에서 약간의 증가를 보였다(P<0.07). Ca(P<0.06)과 P(P<0.01)의 소화율은 모두 extrusion된 쌀겨에 phytase의 첨가수준이 다를 경우 500 unit보다는 1,000 mini에서 더 좋은 효과를 보였다. 분 중 P 배설량(2.72g/d vs 3.89g/d)은 extrusion된 쌀겨보다는 extrusion된 쌀겨에 phytase을 첨가하므로서 줄어들었다(P<0.08). 또한 phytase의 첨가수준이 증가할수록 P의 축적량이 증가함을 알 수 있었다(P<0.04). 한편 Ca 섭취량, 배설량 및 축적량은 모든 처리구 간에 통계적인 유의성을 찾아볼 수 없었다. 그러나 최종 Ca 축적량은 쌀겨에 비해 extrusion된 쌀겨의 경우 15%가 향상되었다(6.64g/d vs 5.77g/d). An experiment was conducted to determine the effects of microbial phytase and feed processing on production and phytate P utilization of pigs. Four crossbred barrows with average initial body weight of 30㎏ were used in 24-d metabolism experiment(4 x 4 latin square) to determine the effect of extruded rice bran and phytase supplementation on nutrient utilization. Digestibility of DM in pigs fed extruded rice bran with phytase improved compared to that in pigs fed extruded rice bran(P<0.04). N digestibility was greater for extruded rice bran than rice bran(P<0.07). However, there was no effect of phytase supplementation to extruded rice bran. Digeshbilities of Ca(P<0.06) and P(P<0.01) were greatest for extruded rice bran with phytase 1,000 unit. Fecal excretion of P(2.72g/d vs 3.89g/d) was less for extruded rice bran with phytase than without phytase(P<0.08). Also, when phytase supplementation was increased in diet, there was increased P retention(P<0.04). There were no treatment effects intake, excretion and retention of Ca. However, Ca retention improved by 15% in extruded rice bran compared to rice bran(6.44g/d vs 5.77g/d).

조사료의 종류가 홀스타인 송아지 유선의 발달 , 반추위 돌기 및 성장률에 미치는 영향

조광근,최윤재,박영우,윤연화,한영근,윤상기,권웅기 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.6

본 연구는 홀스타인 송아지에 대한 세 종류의 조사료가 유선조직, 반추위 유두, 번식성적 및 성장률에 미치는 영향을 조사하기 위하여 실시하였다. 출생 후 4일된 송아지(42.9±0.9㎏) 24두를 무작위로 선발하여 출생 후 4∼44일까지 전유를 급여하다가 45일에 그룹 1은 볏짚, 그룹 2는 오차드 그래스, 그룹 3은 알괄파를 급여하였다. 또한 유선조직과 반추위의 발달을 측정하기 위하여 3, 9, 18개월령에 도달하였을 때 각 처리구의 송아지를 1마리씩 도살하였다. 알팔파를 급여한 그룹 3은 다른 처리구에 비하여 중체율이 높았으며, 그룹 2는 영양소 이용률과 번식성적이 높은 경향을 나타내었다. 반추위의 무게는 3개월령 도달시에는 그룹 3이 가장 무거웠으나, 9개월과 18개월령 도달시에는 그룹 2에서 가장 무거운 것으로 나타났다. 반추위의 유두 수는 유두의 성장과 함께 일반적으로 감소하는 경향을 나타내어 유두의 길이와 유두 수와는 서로 상대적인 관계를 나타내었다. 유선의 기능적 활성을 나타내는 RNA/DNA 함량은 3개월 시에는 그룹 3이 가장 낮은 경향을 보였으나 9, 18개월 시에는 반대로 가장 높은 경향으로 나타났으며, 유선세포의 크기를 나타내는 protein/DNA 함량은 18개월 시에 그룹 2가 가장 높은 경향을 보였다. 결론적으로 본 연구에서 볏짚은 반추위의 초기 발달을 촉진하고 알팔파와 오차드그래스는 성장과 번식성적을 증가시키며 또한 초기에 유선의 발달을 촉진시키는 것으로 나타났다. Twenty-four Holstein calves were used to evaluate the effects of three different forages on growth and reproductive performances, and ruminal papillary and mammary developments. Four-day-old Holstein calves weighing 42.9±0.9 ㎏ were randomly assigned to three forage groups of rice straw (group 1), orchard grass hay (group 2), and alfalfa (group 3). All calves received whole milk from day 4 through day 44. At 45 days of age, the animals were assigned at random to one of the three dietary treatments. When calves reached the ages of 3, 9, and 18 months, one calf in each group was sacrifced for evaluation of ruminal and mammary tissue developments. Calves of group 3 gained more body weight than those of other groups, while group 2 showed an effective nutrient utilization and reproduction performance. At 3 months, the stomach weight of group 3 was the highest, however, group 2 provided the highest stomach weight at 9 and 18 months. A remarkable reduction in papillae number was observed in the rumens of all 3- to 9-month-old heifers. A decrease in number of these papillae was observed in all groups exhibiting papillary growth. There was a reciprocal relationship between the number and the length of ruminal papillae. Among the 3-month-old calves, the functional activity (RNAI DNA contents) of the mammary glands of group 3 was lower than those of other groups, whereas the trend was opposite for 9- and 18-month-old heifers. The size of mammary cell (protein / DNA contents) was the greatest for group 2 at 18 months of age. The results suggest that rice straw stimulated earlier development of rumen. Alfalfa and orchard grass improved the growth, reproduction performance, and earlier development of mammary glands.

지하철의 사상사고 및 운전장애 분석에 관한 연구

이동훈,목연수,장성록,권혁무,윤원영,옥영석,최용석,배동철 한국산업안전학회 1999 한국안전학회지 Vol.14 No.3

The purpose of this study is to analyze death injuries and operation troubles of urban transit. No difference was shown in death rates between Line 1 of Pusan urban transit and Line 5, 7, and 8 of Seoul metropolitan transit. And relief time by another train did not depend upon the number of crews. We concluded that thorough inspection and preventive maintenance of trains and facilities are necessary for safe and timely service of urban transit.

HVOF 용사법으로 제조된 TiC-Fe 합금 코팅층의 내마모 특성에 미치는 열처리 영향

김문철,박찬경,진현우,김현민,최상준,권순주 대한금속재료학회(대한금속학회) 2000 대한금속·재료학회지 Vol.38 No.1

The physical soundness, microhardness and wear properties of the thermally sprayed TiC-Fe wear-resistant coatings have been investigated. Thermally sprayed coatings were fabricated by HVOF and the subsequent heat-treatments were carried out at temperatures ranging from 800℃ to 1000℃ in either vacuum or air for 30 minutes. The wear resistance of the as-sprayed TiC-Fe alloy coatings was found to be better than that of Cr₃C₂-NiCr alloy coatings and similar to that of WC-Co coatings. In addition, the wear resistance and hardness of the coating were improved by the following heat-treatment in vacuum(∼10^(-3)torr). The maximum improvement in wear resistance and microhardness was about 20 and 30%, respectively by the heat-treatment performed at 900℃ in vacuum, while the heat-treatment in air deteriorated the wear property due to oxidation. It has been revealed, from TEM and Mo¨ssbauer studies, that the improved wear resistance in the heat treated coating was mainly caused by the hardness increase associated with martensitic transformation. However, no improvement in the wear resistance of the TiC-Fe coatings heat-treated in air seemed to be caused by the residual stress due to the oxidation of Fe matrix.

무가압 침투법에 의해 제조된 Al/BN 복합재료의 미세조직과 인장성질

조수연,이건배,심호섭,허성우,유황룡,권훈 대한금속재료학회(대한금속학회) 2000 대한금속·재료학회지 Vol.38 No.12

Spontaneous infiltration and strengthening behaviors were analyzed in terms of microstructures and tensile properties of Al/BN composite fabricated by pressureless infiltration technique, compared with control alloy without BN fabricated by the same method. The Mg₃N₂ formed by the reaction of Mg vapor and nitrogen gas, which coated the particles in the powder bed, is believed to induce spontaneous infiltration through a great enhancement of wetting via the following reaction, Mg₃N₂+ 2Al→2AlN + 3Mg. This was identified by the finding of AlN particle layers on the surfaces of old Al particles in the powder bed, which contacted with the infiltrating melt. In addition, unreacted Mg₃N₂ was observed outside the composite, where the Al melt directly did not come into contact. Fine AlN particles formed in-situ resulted in a significant strengthening even in the control alloy with no addition of BN. In the composite reinforced with BN, additional AlN was formed by the interfacial reaction of the BN and Al melt as well as AlN by the in-situ reaction. Consequently, both the BN particles and the additional AlN particles formed by the interfacial reaction led to a further strengthening in the composite, as compared to control alloy strengthened by the AlN particles formed in-situ.

실리콘고무의 가교제 변화에 의한 유전특성

권병휘,이성일,홍진웅,이준웅,이원재 한국고무학회 1987 엘라스토머 및 콤포지트 Vol.22 No.1

The characteristic of the dielectric relaxation in silicone rubbers were studied in the frequency range of 1×10²∼3×10^6 ㎐ at the temperature range of 30℃∼170℃. As the results of the study, it has been confirmed that the silicone rubber containing the cross-linking agents of 2,5-bis(tert-butylperoxy)-2,5-dimethyl hexane exhibit the dissipation spectra of two kind(α, β dissipation) due to the siloxane and methyl groups. Particularly, the maximum value of dielectric loss spectra of silicone rubber combinning the cross-linking agents of 0.7phr to 1.0phr are on the increasing in high frequency region, but the specimen of above 1.0phr become smaller again The energy and the entropy of activation on the molicular motion obtained 18.32㎉/mole and 1.48㎈/mole·deg in measuring condition respectively.

순 AI 과 순 Cu 의 진동 특성에 미치는 시편 크기의 영향

장충근,권혁무,박헌범 대한금속재료학회(대한금속학회) 2001 대한금속·재료학회지 Vol.39 No.4

The vibration properties of the pure Al plate and pure Cu plate, 12 ㎜ wide and 164∼254 ㎜ long, were investigated by cantilever beam and RFDA to get the following results. (1) The results by cantilever beam method and RFDA show that the resonance frequency decreases as the specimen length increases or the thickness decreases. (2) When measuring the vibration by the cantilever beam method, the vibration damping coefficients are stable at the specimen with 184 ㎜ or higher length. (3) When measuring the vibration damping coefficient by the cantilever beam method, the mean vibration damping ratio of Al specimen 1.6∼0.8 ㎜ thick is 3.1×10^(-2) and 4.0×10^(-2) in Cu specimen of 2.0∼1.2 ㎜ (4) When measuring the vibration damping properties by the RFDA, vibration damping coefficients are similar regardless of the length and thickness of a specimen and the mean vibration damping ratios of Al and Cu were 2.1×10^(-2) and 2.7×10^(-2), respectively. (5) As a result of (3) and (4), The relationship, between the vibration damping ratio measured by the cantilever beam method and it by the RFDA was founded as g_s=(δ_o/δ_r)×(1/1.5).

LDPE 에서 발생된 전기트리에 수반된 내부 부분방전 펄스 해석

박영국,임기조,강성화,권순석,신태수 한국산업안전학회 1999 한국안전학회지 Vol.14 No.1

전력용 케이블은 전선로의 지중화 추세에 따라 사용이 증가하고 있다. 케이블 절연체의 경우 장기간의 전압인가에 의해 열화 및 절연파괴 된다. 전력용 케이블의 절연파괴시 발생하는 사회/경제적 문제는 매우 심각한 것으로 알려져 있다. 절연체의 열화에 영향을 주는 요인은 매우 복잡하지만 그중에서도 전기트리 열화에 의한 파괴는 비교적 두꺼운 고체 유전체인 경우에 절연파괴 사고의 주된 원인이 되고 있다. 전기트리의 개시나 진전시 부분방전이 발생하므로 부분방전의 검출에 의해 전기트리의 발생 및 진전 양상을 관측할 수 있고 부분방전의 해석에 의해 절연재료의 잔여 수명을 예측할 수 있다. 본 논문에서는 고전압 전력용 케이블 절연재로써 광범위하게 사용되고 있는 저밀도 폴리에틸랜 시편에서의 전기트리 진전 양상을 비파괴 진단 기법에 의하여 검출하고자 내분 부분방전을 관측/해석하였다. The correlation between propagation of electrical tree and internal partial discharges is discussed. We use specimens with needle-plane electrode system made of LDPE(Low Density Polyethylene), observed inception and propagation of electrical tree by optical microscope and investigated the characteristics of the partial discharge (PD) pulses accompanying with propagation of electrical tree. In the specimens with needle-shaped void, the tree propagates branch type. The length of the tree has good linear relation with average discharge power of PD pulses. In the specimens without needle-shaped void, the tree grows bush type tree. The correlation between the area of the tree and the average discharge power of PD pulses has linear relation.

요소 - 전분 단백질사료 제조조건 및 반추위내 소실율에 관한 연구

신형태,정기환,권오광 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.5

본 연구는 요소와 옥수수, 타피오카 및 알팔파를 주원료로 extrusion하여 사료적 가치와 경제성이 높은 요소-전분 단백질사료를 만들기 위한 적정 배합비 작성과 extrusion 조건 및 제조 후 특성과 배양시간별(0.5, 1, 2, 4 및 8시간) 반추위내 소실을(in situ)을 조사하기 위하여 실시하였다. 사료 및 경제적 가치가 높고 extrusion 효과가 양호한 배합비는 Ulea-Corn : urea 38%, corn 45%, alfalfa 12%, molasses 2% 및 tallow 3% ; Urea-Tapioca : urea 38%, tapioca 45%, alfalfa 12%, molasses 2% 및 tallow 3% ; Urea-Alfalfa : urea 40%, Tapioca 10%, alfalfa 45%, molasses 2% 및 tallow 3%였다. 경제적 가치가 높은 요소-전분 단백질사료 제조조건은 원료사료의 수분 함량, 10∼15%; mesh size, 2㎜ 이하; 요소 40% 이하였으며 extruder의 screw speed, 400rpm; extrusion 온도, 120∼150℃; die size, 5∼10 ㎜ 였다. 제조된 요소-전분 단백질사료의 조단백질 함량은 Urealea-Corn이 105.2%, Urya-Tapioca가 105.0%였고 Urea-Alfalfa는 109.85%로 제조과정에서 조단백질 함량이 다소 감소하는 것으로 나타났다. Urea-Corn, Urea-Tapioca 및 Urea-Alfalfa의 팽화율은 각각 1.11%, 1.5% 및 1.38%로 나타나 Urea-Tapioca의 팽화율이 높았으나 처리간에 유의적인 차이는 없었다. Extruding 후 Urea-Corn(UC)은 전분을 싸고 있는 protein matrix가 파괴되어 전분의 일부가 외부로 노출되는 것으로 나타났으며, Urea-Tapioca(UT)는 endosperm cell의 안정된 구조가 파괴되어 전분의 노출정도가 높은 것으로 관찰되었다. 압출공정 후 공기중에서 2개월이 지난 후에도 사료의 외관상 부패현상이 일어나지 않았으며 가스 발생도 없었다. 반추위내 배양 후 30분과 1시간째 Urea-alfalfa(UA)의 반추위내 건물소실율(%)은 Urea-corn (UC)이나 Urea-tapioca(UC) 보다 유의적으로 높았으며(p<.05) 배양 4시간과 8시간째에는 Urea-tapioca의 건물소실율이 UC나 UA보다 높았다(p<.05). 배양초기(30분 및 1시간) 반추위내 조단백질 소실율(%)은 UA와 UC가 UT보다 높았는데 UC의 조단백질 함량은 배양 30분 후 약 67%가 소실되었으며, 배양 2시간째 약 84%가 소실된 후 8시간째까지 큰 차이가 없었다. UT의 경우 배양 30분 후 약 44%의 조단백질이 소실되었으며, 이후 4시간째까지 86%가 소실되었으나, 4시간 이후에는 약 2%만이 소실되어 조단백질은 급여 4시간 이전에 주로 소실되는 것으로 나타났다. UA의 반추위내 조단백질 소실율도 배양 30분 후 약 50% 정도가 소실된 후 4시간째까지 85%가 서서히 소실되었으나 8시간째에는 약 86%가 소실되어 4시간 이후에는 소실율이 낮았다. These studies were conducted to promote usage of urea as a protein source for ruminants. Extruded urea-starch complex(USC) were made through extrusion using urea as a high protein source, corn and tapioca as a starch source, and alfalfa to produce economical and nutritional protein feed for ruminants. The rate of degradation of the dry matter and crude protein of urea-starch complex, when incubated in nylon bags in the rumen, was studied in rumen cannulated Holstein cows The economical formula of extruded urea-starch complex were three types, Urea-Com(UC) urea(38%), corn(45%), alfalfa(12%), molasses(2%) and tallow(3%); Urea-Tapioca(UT) : urea(38%), tapioca(45%), alfalfa(12%), molasses(2%) and tallow(3%); Urea-Alfalfa(UA) : urea(40%); tapioca(10), alfalfa(45%), molasses(2%) and tallow(3%) respectively. The optimum condition of extruder for making of extruded urea-starch complex were as follows : moisture contents, 10∼15%; mesh size, maximum 2㎜; screw speed, 400 rpm; temperature, 120∼150℃ and die size, 5∼9㎜. Crude protein contents of UC, UT and UA were 105.20%, 105.00% and 109.85%, respectively. The expansion rate of UC, UT and UA were 1.11%, 1.50% and 1.38%, respectively In situ dry matter disappearance of UC at 0.5 and 1 hour in the rumen was siginificantly higher compared with UT and UA and, UT showed higher values of in situ dry matter disappearances than that of Urea-Alfalfa and Urea-Corn at 4 and 8 hour after incubation(p<.05), but no significant difference was observed between UC and UA. In situ crude protein disappearance of UT and UA at 0.5, 1 and 2 hour in the rumen was siginificantly lower compared with UC, but no significant difference was observed between treatments at 4 and 8 hours.

만성신부전증에서 혈청 CEA치에 관한 연구

이정상,신영태,정순일,고창순,김성권,표희정,권인순 대한핵의학회 1980 핵의학 분자영상 Vol.14 No.2

저자들은 1979년 3월부터 1980년 10월까지 서울대학교병원내과에 입원하여 만성신부전증으로 진단받고 혈액투석요법을 받지 않은 환자 15예, 혈액투석요법을 시행중인 환자 39예 및 신장이식술을 받고 신장능이 호전된 환자 23예에서 혈청 CEA치를 방사면역측정법으로 측정하여 정상대조군과 비교하여 다음과 같은 결과를 얻었다. 1) 정상 성인 65명의 혈청 CEA치의 범위는 1.0∼4.3 ng/ml이었으며 평균은 1.6±0.66 ng이었다. 2) 혈액투석요법을 시행치 않은 만성신부전증 환자 15예의 혈청 CEA치는 0.3∼8.3 ng/ml이었고 평균은 3.6±2.10 ng/ml로써 정상대조군에 비하여 유의하게 증가되어 있었다(p$lt;0.001). 3) 혈액투석요법으로 치료중인 만성신부전증 환자 39예의 혈청 CEA치는 0.7∼6.7 ng/ml로 평균이 3.0±1.52 ng/ml이며, 정상대조군에 비하여 유의하게 상승되어 있으나(p$lt;0.001), 혈액투석을 받지 않은 환자군과는 유의한 차이가 없었다. 4) 신이식 환자 23예의 혈청 CEA치의 분포는 1.8∼10.8 ng/ml이고 평균은 3.8±1.96 ng/ml로 역시 정상대조군에 비하여 유의하게 증가되어 있으나(p$lt;0.001), 만성신부전증 환자군과는 유의한 차이가 없었다. 5) 이상의 혈청 CEA치가 정상범위 이상으로 상승된 49명��환자중 이학적 소견이나 검사소견상 악성종양은 발견되지 않았다. The serum CEA levels were measured by radioimmunoassay technique in 15 patients with chronic renal failure, who were not treated with hemodialysis, in 39 patients under hemodialysis and in 23 patients who received renal transplantation. The results were compared with those in 65 normal adults and the following results were obtained. 1) Serum CEA concentrations in 65 normal adults were in the range of 1.0 to 4.3 ng/ml with a mean value of 1.6±0.66 ng/ml. 2) Serum CEA concentrations in 15 chronic renal failure patients who were not treated with hemodialysis, were in the range of 0.3 to 8.3 ng/ml with a mean value of 3.6±2.10 ng/m1 which was significantly higher than those of normal controls(P$lt;0.001). 3) Serum CEA concentrations in 39 chronic renal failure patients under hemodialysis were also much higher than normal controls(p$lt;0.001), but not significantly different from those of the patients who were not under hemodialysis(P$gt;0.05). 4) In 23 patients who received renal transplantation, serum CEA levels were snificantly higher than normal controls(P$lt;0.001), but not significantly different from those of chronic renal failure patients.