• 한국식생활문화학회지
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• 제22권5호
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• pp.645-651
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• 2007

Male weanling Sprague Dawley rats were used to evaluate the effect of dietary rice starch with different particle size on growth performance, intestinal function and proliferation. There were two dietary treatment: rice starch (RS), ultra finely pulverized rice starch with less than $15{\mu}m$ size (PRS). They were eight rats per treatment. In vitro digestibility, body weight change and organs weight were evaluated. Serum GPT, GOT and blood urea nitrogen were analyzed. Transit time, short chain fatty acid contents of cecum, and cell proliferation of duodenum and jejunum were measured. In vitro digestibility of PRS was higher than that of RS. Rats fed ultra finely pulverized rice starch for 3 weeks grew faster than rats fed rice starch. PRS group has higher weights of liver, kidney, spleen and epididymal fat pad, perhaps as a result of increased digestibility. GPT and GOT were not different between two groups. Blood urea nitrogen was higher in RS-fed rats than that of PRS-fed rats. Feeding ultra finely pulverized rice starch resulted in a proliferation of duodenum significantly. These results suggest that ultra finely pulverized rice starch increases the growth performance in weanling animals with reduced number of cells in the cell cycle of small intestine.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.651-654
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• 2001

A study was made of the efficiency of ammonia N retention by Jowar kadbi (sorghum straw), initially 6.41% crude protein (CP), treated with 4% urea solution. After 30 days the CP in straw that was unchaffed and had been left uncovered was 10.02, and in chaffed straw that had been covered with a polythene sheet was 10.9%. The two treated straws were each fed to six crossbred (HF$\times$Deoni) calves, initially $12{\pm}2$ months old and $86.7{\pm}3.2kg$ bodyweight. They were also given two isocaloric (70% TDN) and isonitrogenous (20% CP) concentrate mixtures differing in calculated Rumen Degradable to Undegradable Dietary Protein ratio (RDP:UDP). Those fed the unchaffed uncovered treated straw (treatment C) received 65 RDP:35UDP and the other group (T1) received concentrate with a 55:45 ratio. The T1 group had the higher DM intake (p<0.01) in total (306 vs 268 kg), per day (4.1 vs 3.6 kg) and per unit bodyweight. Digestibility of DM, OM, CP and NDF, but not ADF, was higher in T1 and that group had the higher daily gain (517 vs 333 g) and higher total gain (38.8 vs 25.0 kg) over the 75 d of the feeding trial. It is concluded that chaffing and covering of Jowar kadbi treated with urea, not likely to be adopted by farmers because of financial constraints, does not confer important benefits. A concentrate supplement (estimated 45% of the CP as UDP) to calves given the treated straw has a beneficial effect on their growth and development.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1255-1261
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• 2005

The objective of this study was to evaluate the net flux response of nitrogen compounds (alpha-amino N, ammonia N, urea N, essential amino acids) across the portal-drained viscera (PDV), liver and total splanchnic tissues of mature wethers to increasing level of dietary fishmeal (FM) supplementation. Four wethers (average body weight, 64 kg) with chronic indwelling catheters into the portal, hepatic and mesenteric veins and the abdominal aorta were used in a 4${\times}$4 Latin square design. A basal diet consisting of 0.7 hay and 0.3 concentrate was fed twice daily with a fixed amount at 1.4 times maintenance energy (1.3 kg/day on a dry matter basis). The supplementation proportion of FM as treatment was 0, 0.03, 0.06 and 0.09 to the amount of the basal diet to contain 119, 137, 154 and 170 g crude protein per kg dietary dry matter, respectively. Blood flows through PDV and liver did not differ (p>0.05) among the treatments. Both net PDV release and hepatic uptake of alpha amino acid N increased linearly (p<0.05) in response to increased dietary FM, which resulted in similar total splanchnic release of alpha-amino N among the treatments. Similarly, increased dietary FM increased net PDV absorption and hepatic removal of ammonia N linearly (p<0.05). Hepatic synthesis and total splanchnic release of urea N increased linearly (p<0.01) with increased dietary FM, but PDV uptake of urea N did not respond to increased dietary FM. Linear regression equations between the increases in FM N intake and PDV net flux indicated that 0.34 and 0.30 of FM N was absorbed in the form of alpha-amino N and ammonia N, respectively. The results demonstrated that FM supplementation provides more alpha-amino N than ammonia N to the liver, but the alpha-amino acid N absorption is less than the expected metabolizable protein N from FM supplementation.

• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1300-1306
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• 2002

Fourteen non-descript zebu cattle calves of about 1 year and 6 months age and 111 kg average body weight were used in this experiment. Grazing (5 h daily) animals were supplemented with urea-molasses blocks with and without Yucca, while the control group was without any supplementation i.e. grazing only. The feeding trial continued for a period of 70 days (November to February). At the end of trial three animals per treatment were slaughtered to compare carcass traits. Group no. 1 was fed block with yucca, group no. 2 was fed block without yucca and group no. 3 was on grazing only. Block intake was found to be 724 g/h/d and 1,239 g/h/d for group no. 1 and group no. 2, respectively (p<0.05). Feed efficiency of blocks was found to be 2.71 kg and 4.86 kg for group no. 1 and group no. 2, respectively (p<0.05). Block intake per kg $BW^{0.75}$ was found to be 14.75 and 26.05 gram for group 1 and group 2, respectively (p<0.05). Average daily body weight gain was found to be 267 g/h/d, 255 g/h/d and 169 g/h/d for group 1, 2 and 3, respectively. Carcass traits among the three treatments were found to be statistically similar. Thus urea-molasses blocks supplementation improved body weight gain and addition of yucca in the blocks further improved body weight gain, feed efficiency and economics. Environment (ambient temperature, rainfall, wind and humidity) had no significant effect on three treatments.

• 한국토양비료학회지
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• 제20권4호
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• pp.337-340
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• 1987

규회석 분말을 시용하는 경우와 시용하지 않는 경우에 가을배추(삼진)에 대한 칼리비료와 요소, 질산 암모니아의 병, 단용효과를 밝히고자 삼각사양토에서 실시한 시험결과는 다음과 같다. 1. 규회석 분말의 사용은 배추재배를 비교적 용이하게 하였다. 이 조건하에서 배추에 대한 요소와 질산 암모니아의 효과는 차이가 없었다. 2. 규회석 분말을 사용하지 않는 토양에서는 요소보다 질산 암모니아가 배추를 증수하게 하였으며 그 효과는 더 많은 토양칼리을 이용하게 한데 기인하였다. 3. 칼리의 병용은 배추의 수량을 높일 뿐만 아니라 가식부의 생산비를 높였으며 그 효과는 특히 규회석분말을 쓰지 않는 토양에서 컸다. 4. 칼륨은 배추의 외엽에서 내엽으로 쉽게 이동했으며, K원으로서 외엽의 그 함량이 배추의 수량을 지배해서 건조 외엽의 함량 20me/100g 이하에서는 배추의 생체중이 직선적으로 감소하였다.

• 농업과학연구
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• 제40권2호
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• pp.123-129
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• 2013

An experiment was conducted to evaluate the effects of nitrogen supplementation through urea-molasses multinutrient block (UMMB) on the performance of dairy cows fed good quality forage based diets with rice straw as a night feeding. A total of 10 multiparous crossbred dairy cows in their early lactation were grouped into two categories based on their breed, parity, body weight, milk yield, milk fat and protein contents and daily fed a chopped CO-3 grass (Pennisetum purpureum ${\times}$ Pennisetum americanum; hybrid Napier) ad-libitum, 1 kg of dairy cow concentrate feed during the day time and 5 kg of rice straw (dry matter basis) at night as the basal diet (control) for 5 wk. In addition to the basal diet, the treatment group received 300 g of crushed UMMB daily throughout the experimental period. Cows were milked twice daily and the milk yields were recorded. Milk and feed samples were collected weekly for chemical analysis. Supplementation of UMMB had no significant effects (p>0.05) on straw intake, daily milk yield, contents and yields of milk constituents such as milk fat, protein, lactose and solids-non-fat. In addition, milk urea nitrogen content were not affected (p>0.05) by UMMB supplementation. However, numerical increments in all the parameters measured were observed during the study in cows fed diets supplemented with UMMB. It can be concluded that nitrogen supplied through UMMB had no effects on production performances of dairy cows in this study.

• 한국식품저장유통학회지
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• 제5권1호
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• pp.65-71
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• 1998

The changes in gel characteristics of soy protein as a result of various reagents that alter specific interactions which affect the formation and textural properties of gels, were studied. The reagents were added to 15% soy protein solutions prior to heat treatment. The gels were not formed with urea, indicating that hydrogen bonds significantly contributed to the formation and hardness of soy protein gel. Hydrophobic interactions and disulfide bonds compensated for hydrogen bonds and the contributions of electrostatic interactions to gel hardness are relatively insignificant. The farce primarily responsible for gel cohesiveness appeared to be disulfide bonds, because a significant decrease in cohesiveness was found only with the presence of N-ethylmaleimide. Adhesiveness decreased only with the addition of urea, and thus the contribution of hydrogen bonding to adhesiveness of gel could be concluded to be resent. However, adhesiveness was suggested to be interpreted not only wile molecular forces involved in gel formation but also with hydration properties of protein.

• 한국분무공학회지
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• 제18권4호
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• pp.196-201
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• 2013

SCR(Selective Catalytic Reduction) is a major after-treatment solution to reduce NOx emission in recent diesel engines. In this study, a metal foam is applied as an alternative SCR substrate and tested in a commercial diesel engine to compared with a conventional ceramic SCR system. Basic engine test from ND-13 mode shows that a metal foam catalyst has lower NOx conversion efficiency than a ceramic catalyst especially over $350^{\circ}C$. A metal foam catalyst has characteristics of high exhaust gas pressure before a SCR catalyst and high heat transfer rate due to its material and structure. NOx conversion efficiency of a metal foam catalyst shows an increasing tendency along with the increase of exhaust gas temperature by $500^{\circ}C$. The effect of urea injection quantity variation is also remarkable only at high exhaust gas temperature.

• 한국세라믹학회지
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• 제33권12호
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• pp.1380-1386
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• 1996

The effects of urea addition and reaction conditions were examined in the prepareation of zirconia coated SiC whiskers through surface precipitation taking place during high-temperature aging of Zr(SO4)2 solutions containing the whiskers. More dense zirconia-hydrate was precipitated on the surfaces of the whiskers in the presence of urea. The ratio of the concentration of Zr(SO4)2 to the amount of added whiskers was the most important factor to confine the precipitation of zirconia-hydrate only at the surfaces of the whiskers The from of the coating layers was unchanged after heat-treatment leading to the dehydration and crystallization of the layers.

• 한국세라믹학회지
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• 제33권6호
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• pp.693-699
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• 1996

YIG precursor powder was obtained by homogeneous precipitation in chloride salt solution by thermal decom-position of urea. It was found that ferric ions precipitated prior to yttrium ions. The precipitate was minute and spherical in shape. The precipitate formed consisted of the mixture of amorphous and ferric oxyhydroxide. Crystallization of YIG was proceeded by solid state reaction of intermediate YFeO3 and Fe2O3 in the temperature range of 85$0^{\circ}C$ to 140$0^{\circ}C$. Single phase of YIG was obtained by heat-treatment of the powder at 140$0^{\circ}C$ for 6 hrs in air. The powder calcined was molded into pellets and sintered in air. The maximum density of 4,92 g/cm3(95.1% of theoretical density) was obtainable for the pellet sintered at 145$0^{\circ}C$ using the powder calcined at 90$0^{\circ}C$.