• 공업화학
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• 제24권2호
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• pp.165-170
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• 2013

초고온가스로 핵연료 구형 UCO (uranium oxycarbide) 입자 제조과정 중 중간화합물 제조에서 적용하고 있는 내부겔화공정을 대체하기 위해 외부겔화공정을 도입하는 연구가 진행 중에 있다. 외부겔화공정을 이용해서 구형 UCO입자를 제조하기 위한 사전실험으로, 중간화합물인 ADU (ammonium di-uranate) 겔 입자를 제조하기 위한 원료용액인 모사 broth 용액을 제조하여 카본블랙 입자를 분산시키는 실험이 수행되었다. 다양한 종류의 카본블랙 입자를 사용해서 모사 broth 용액에 분산실험을 수행한 결과, Cabot G 제품이 용액상에서 분산안정성과 균일한 분산상태를 나타내고 있어서, 본 연구의 카본블랙으로 선정되었다. 또한 나노크기 입자로 응집된 카본블랙 입자를 고점성 액상물질에 효율적으로 분산시키기 위해서는, 금속염용액에 카본블랙 입자를 투입하고 ultrasonic force를 이용해서 응집입자를 해체한 다음, 고점성 물질인 PVA (poly vinyl alcohol)를 투입하여 강력한 기계식혼합기를 이용해서 6000 rpm으로 2차 분산 혼합시키는 경우, ultrasonic force에 의한 broth 용액의 물성이 유지되면서 카본블랙 입자의 분산안정성과 분산상태가 양호한 broth용액을 얻을 수 있었다.

• 한국응용과학기술학회지
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• 제3권2호
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• pp.49-64
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• 1986

This experiment is carried out to study effect of choline-deficient diet on serum and liver lipid contents of male rats. The experimental animals use 36 male Sprague-Dawley rats weighing about $100{\pm}3g$. They are classified into 7 groups and fed to experimental diets which are composed of 0.8% choline-supplement of deficient diets in addition to 14% corn oil, 14% corn margarine and 14% lipids mixed with 4% corn oil and 10% corn margarine, respectively. After feeding for 4 weeks, I measure lipid concentration of serum and liver, and the result are as follows. 1. The choline-deficient diet group decreases slightly the rates of weight gain and feed efficiency as compared with those of the choline-supplement diet group, but increases liver weight. 2. The choline-dificient diet group decreases the serum concentrations of total cholesterol (TC), free cholesterol, HDL-choelsterol, VLDL, LDL-cholesterol and phospholipid (PL), but increases the contents of triglyceride and the ratios of cholesterol/HDL-cholesterol and triglyceride/PL, and indicates no remarkable-difference in the ratio of TC/PL. 3. As compared with the choline-supplement diet group, the choline-deficient diet group contains the higher liver contents of total lipids, free cholesterol and triglyceride, and gives little difference in the liver contents of total cholesterol and phospholipid(PL), and presents the higher ratios of VLDL, LDL-cholesterol/HDL-cholesterol and TG/PL in the liver.4. In the choline-deficient diet group, the coutents of serum and liver lipid is not influenced by the kind of dietary fat. On the other hand, the choline-supplemented diet group indicates a significantly lower content of phospholipid in the corn margarine-added diet group than in the corn oil-added diet group. As aforementioned results, I think that the choline-deficient diet induces fatty liver in male rats without relation to kind of fatty acid, and cholines-upplement diet with saturated fatty acid makes the more decrease of liver phospholipid than that with polyunsaturated fatty acid.

• 한국어병학회지
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• 제20권2호
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• pp.139-145
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• 2007

인체에 널리 사용되고 있는 Aspirin (ASA)을 양식 뱀장어 (Anguilla japonica) 약욕 또는 경구 투여한 다음 혈장 중의 ASA와 salicylic acid (SA)의 양을 HPLC로 측정하였다. 뱀장어 혈장은 0.2 M HCl과 0.2 M orthophosphoric acid로 산성화시킨 다음 acetonitrile과 혼합하여 ASA와 SA를 추출하였다. 2약제의 정량은 Novapak C18과 UV detector (237 nm)가 장착된 HPLC로 측정하였다. 이 때 이동상은 740 ㎖의 증류수, 900 ㎕의 orthophosphoric acid와 180㎖의 acetonitrile을 사용하였다. ASA, SA 및 내부 표준물질로 사용한 2-methylbenzoic acid (MBA)의 retention time은 각각 4.8분, 8.4분 및 11.4분이였으며, 측정한계 농도는 ASA가 0.05 ㎍/㎖, SA는 0.01 ㎍/㎖였다. 혈장으로 부터의 평균회수율은 ASA가 70.8-99.6%, SA는 95.2-100.3%였다. 뱀장어에 ASA를 약욕 (20 ppm) 또는 경구투여 (50 ㎎/kg BW) 한 다음 채취한 혈장을 시료로 이 방법으로 ASA와 SA의 양을 측정한 결과 단지 SA만 검출되어졌고, ASA는 검출되지 않았다. 이는 ASA가 혈장내에서 신속히 SA로 분해되기 때문으로 판명되었다. 또 ASA에 약욕시킨 경우에는 약욕 후 3시간후에 혈장내의 SA양이 최고치에 도달하였으며, 경구투여 한 경우에는 7일후에 최고치에 도달하였다. 한편 ASA를 투여한 다음 ASA 무첨가 수조에 수용한 결과 2투여 경로 모두 48시간 이후에는 SA가 0.02-0.03 ㎍/㎖이 검출되어 잔류의 문제도 거의 없었다. HPLC를 이용한 혈장내의 ASA와 SA의 검출법은 신속하며 정확한 방법으로 뱀장어 이외의 어류에도 활용 가능할 것으로 생각된다.

• Ocean and Polar Research
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• 제25권2호
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• pp.213-226
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• 2003

Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses. During the Arctic field season August 2002, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden. A total of 15 surface samples were collected for the phytoplankton related measurements. Chl a values ranged from 0.08 to 1.4mg chi a $m^{-3}$ (mean of 0.53mg chl a $m^{-3}$) in the overall surface stations. The highest values of the chi a concentrations (> 1.0mg chi a $m^{-3}$) were found near glacier in the northeastern part of Kongsfjorden. Nanoplanktonic (< $20{\mu}m$) phytoflagellates were important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 90% of the total chi a biomass in the study area. Surface temperatures and salinities ranged from 2.5 to $7.18^{\circ}C$ (mean of $4.65^{\circ}C$) and from 22.55 to 32.97 psu (mean of 30.16 psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. The character of surface water due to down-fjord wind was highly similar to phytoplankton distribution. Drifting ice, freshwater, and semdiment inputs from large tidal glaciers located in the inner part of Konsfjorden create steep physico- and biogeochemical environmental gradients along the length of this ford. The glacial inputs cause reduced biodiversity biomass and productivity in the pelagic community in the inner fjord. Primary production of benthic and pelagic microalgae is reduced due to the limited light levels in the turbid and mixed inner waters. The magnitude of glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground fer marine mammals and seabirds. Especially, seabirds play the largest energy intake and also export nutrients for primary production of the marine microalgae. Kongsfjorden has received a lot of research attention as a site for exploring the impacts of climate changes. Dasan Station in Kongsfjorden will be an important Arctic site for monitoring and detecting future environmental changes.

• Clinical and Experimental Pediatrics
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• 제51권3호
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• pp.329-334
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• 2008

Kwashiorkor는 단백질 결핍으로 인한 영양실조로 저알부민혈증, 설사, 피부염, 부종을 증상으로 나타낸다. 단백질-열량 결핍은 면역결핍을 초래하고 이는 감염에 대한 감수성을 높임으로써 생명을 위협하는 상태가 될 수 있다. 치료는 조기 영양공급, 감염증 치료가 주이며, 치료 경과 중 확장성 심근증이 나타날 수 있으며 이 경우 예후가 안 좋다. Kwashiorkor는 주로 빈곤한 나라에서 생긴다고 알려져 왔으며, 기술적으로 진보한 나라에서 치명적인 결과까지 낳은 예는 보고된 바가 없었다. 치명적인 kwashiorkor 1례를 경험하였기에 보고하는 바이다. 환아는 가난때문이 아니라 부모의 잘못된 생각으로 2개월 동안 곡물에 태운 곡식가루만 먹었으며, 설사, 전신 부종, 홍반, 저체온증 등을 주소로 입원하였다. 면역 결핍이 있는 상태였으며, 혈액 배양 검사상 Alcaligenes Xylosoxidans가 동정되었다. 단백질 보충식이 및 항생제 치료, 정주용 면역글로불린치료, 미세영양소 보충하였으나 확장성 심근병증, 다발성 장기 부전으로 사망하였다.

• 한국패류학회지
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• 제27권4호
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• pp.337-343
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• 2011

일본(기수)재첩 유생사육을 위한 최적조건을 파악하기 위하여 수온, 염분, 유생 수용밀도, 먹이생물 종류 및 공급량, 채묘방법에 따른 성장과 생존율을 조사하였다. 일본(기수)재첩의 부유유생은 $24^{\circ}C$와 $27^{\circ}C$에서 빠른 성장을 보였으며, $18^{\circ}C$와 $21^{\circ}C$에서 50% 이상의 높은 생존율을 보임으로서 유생 사육을 위한 적정 수온은 $21-24^{\circ}C$이며, 최적수온은 $24^{\circ}C$ 이었다. 또한 염분 3 psu 이상에서 성장과 생존이 가능하였으나 적정 염분은 6-9 psu 이었다. 유생밀도별 사육시험에서 1 ml당 1-10 개체에서 높은 성장과 생존율을 보였으나 경제성을 고려한 적정 유생사육 밀도는 1 ml당 10 개체였다. 먹이생물에 따른 유생의 성장과 생존율은 Isochrysis galbana, Pavlova lutheri 및 Chaetoceros calcitrans를 혼합하여 10,000-20,000 cells/ml의 밀도로 공급하는 것이 가장 효과적이었다. 성숙유생의 채묘는 모래저질에서 성장과 생존율이 유의하게 효과적이었으며, 특히 0.25 mm 이하의 미세사질에서 높은 생존율을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제2권2호
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• pp.115-121
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• 1989

A comparative slaughter feeding experiment with steer calves weighing 280 kg and a concurrent digestion trial with wether lambs was conducted to study the energy value of rice straw as influenced by ammonia treatment and mixing with alfalfa hay. Steers were ad libitum fed one of nine completely mixed experimental diets: basal (high concentrate); 25 or 50% of untreated rice straw (URS) or ammoniated (plastic covered bales, 4.6% $NH_3$ by weight) rice straw (ARS) proportionately replacing part of the basal; a 50:50 % mixture of URS or ARS and alfalfa replacing a proportion of the basal at 25 and 50%. Digestibility of the nine complete diets (pelleted to prevent sorting) was determined with four ad libitum fed lambs. Ammoniation increased crude protein level (from 3.6 to 10.8%) and in vitro dry matter digestibility of the rice straw by 15%. The improvement in DE, NEm and NEg by ammoniation of rice straw was 20, 52 and 117%, respectively. Ammoniation of rice straw fed as 50% of the diet improved gains over the diet containing 50% URS, but no significant influence on animal performance was observed when rice straw was fed at the 25% level. Each 10% addition of URS to basal diet decreased empty body gain of steers by 116 gram per day compared with a decrease of 70 gram per day when rice straw had been ammoniated. There was no beneficial effect of ammoniation when the roughage component of the diet was a 50:50 mixture of rice straw and alfalfa. Ammoniation of straw and inclusion of alfalfa generally increased the concentration of total volatile fatty acids in rumen fluid. Ammoniation resulted in reduced concentrations of acetic and propionic acid, but increased concentration of butyric acid. Digestibility of URS was improved by mixing with alfalfa. However, alfalfa hay did not influence digestibility of ARS. Diets in which ARS replaced the basal mixture at 25 and 50% had higher NEm and NEg values than comparable URS diets. The same pattern was observed in the straw: alfalfa mixtures, but differences between URS and ARS were significant only for the 50% roughage diets.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.371-377
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• 2009

The objectives of the present study were to investigate the effects of different dietary ratios of whole-crop corn silage and alfalfa hay on nitrogen (N) digestion, duodenal flow and metabolism across the portal-drained viscera (PDV) of growing beef steers, and to elucidate their relationships. Four steers (236${\pm}$7 kg BW) fitted with duodenal cannulae and chronic indwelling catheters into the portal and mesenteric veins and abdominal aorta were used in a 4${\times}$4 Latin square design. Animals were fed (at 12-h intervals) the 4 diets consisting of whole-crop corn silage (C) and alfalfa hay (A) in 80:20 (C8A2), 60:40 (C6A4), 40:60 (C4A6) and 20:80 (C2A8) ratios of which dietary crude protein (CP) was 10.5, 12.0, 13.5 and 15.0% of dry matter (DM), respectively. Feeding level was restricted to 95% of ad libitum intake to measure N digestion, blood flow and net flux of N across the PDV. Digestibility of DM and neutral detergent fiber and digestible energy intake linearly increased as the ratio of alfalfa hay increased. The N intake, duodenal flow and intestinal disappearance increased linearly with increasing alfalfa hay. Arterial and portal concentrations of ${\alpha}$-amino N showed a quadratic response to increasing levels of alfalfa hay and were the highest in steers fed the C6A4 diet. The net PDV release of ${\alpha}$-amino N and ammonia N increased linearly with increasing alfalfa hay, but urea N uptake by PDV did not differ among diets. As a percentage of apparently digested N in the total gut, net PDV release of ${\alpha}$-amino N linearly decreased from 66 to 48% with increasing alfalfa hay. Conversely, net PDV recovery of ${\alpha}$-amino N to intestinal N disappearance varied with increasing alfalfa hay accounting for 49, 50, 58 and 61% on C8A2, C6A4, C4A6 and C2A8 diets, respectively. Net PDV uptake of urea N, relative to apparently digested N, linearly decreased from 81 to 25% as alfalfa hay increased from 20 to 80% of DM intake. Considering PDV uptake of urea N, microbial efficiency and conversion of total tract digested N to PDV ${\alpha}$-amino N net supply, a diet consisting of 80% whole-crop corn silage and 20% alfalfa hay (10.5% CP) was the best, while considering the quantities of intestinal N disappearance and ${\alpha}$-amino N absorption, a diet of 20% whole-crop corn silage and 80% alfalfa hay (15% CP) would be preferred. The proportion of ${\alpha}$-amino N recovered by PDV relative to the intestinal N disappearance may vary with energy intake level of mixed forage diets.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권2호
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• pp.123-127
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• 2003

Chemical burns onto oral mucosa which are infrequent, may result from contact with a wide variety of chemical agents. The degree of injury depends on the chemical, its concentration, duration of contact, and the natural penetrability and resistance of the tissues involved. Chemicals do not usually "burn" in that they do not cause destruction by hyperthermic activity. Rather, they damage tissue by causing coagulation of protein by one of several processes, reduction, oxidation, desiccation, corrosion, or vesication. Paraquat(Gramoxon) is the most frequently agricultural chemicals that induce the severe toxic reactions onto the organs of human body in Korea. The toxic reaction are composed of pulmonary edema and fibrosis, formation of hyaline membrane, inflammatory reaction and bleeding tendency, owing to the cell damage by the production of superoxide radicals. The contents of essential treatment in paraquat intoxication are commonly airway and breathing maintenance, gastric lavage, much hydration and diuresis, hemoperfusion and medications for the removal of the chemicals and the prevention of various complications. The sedative oral dressings, such as, orabase ointment application, warm saline gargling, lidocaine viscous gargling and oral gargling by the mixed solutions(tetracycline, prednisolone and 10% dextrose water) are important for the improvement of chemical oral mucositis and the comfortable feeding of diet. The authors managed properly two cases of oral chemical mucositis that were occurred by the incorrect use of agricultural chemicals(paraquat) and report the cases with the review of literatures about care of the chemical intoxication and oral mucositis.

• 농업과학연구
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• 제3권2호
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• pp.192-197
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• 1976

IKUTON 발효(醱酵) 고구마 전분박(澱粉粕)의 농후사료대축수준(濃厚飼料代蓄水準) 調査하기 위하여 Large Yorkshire, Landrace, Duroc Jersey 삼품종(三品種) 교잡종(交雜種) 25두(頭)를 공시(供試)하여 농후사료(濃厚飼料)를 급여(給與)한 대조구(對照區)와 IKUTON 발효(醱酵) 고구마 전분박(澱粉粕) 10%, 20%, 30% 및 40%를 대치한 5개처리구(個處理區)를 완전임의배치(完全任意配置)하여 시험(試驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 사료섭취량(飼料攝取量)은 40% 구(區)를 제외(除外)한 기타(其他)의 각처리구(各處理區)에서는 대조구(對照區)에 비(比)하여 유의적(有意的) (P<0.05)인 차이(差異)를 인정(認定)할 수 없었으며 40% 이상(以上)의 대체수준(代替水準)에서 사료섭취량(飼料攝取量)이 감소(減少)되고 있었다. 사료효율(飼料效率)은 20% 구(區); 3.43, 30% 구(區); 3.80, 10% 구(區) 3.97, 40% 구(區); 4.20, 0% 구(區0; 4.53의 순(順)으로 대조구(對照區)에 비(比)하여 높은 사료효율(飼料效率)을 나타내고 있었다. 증체량과 80kg 도달주수(到達週數)는 10% 구(區); 12주(週), 0%구(區); 13주(週), 20% 및 30%구(區)가 14주(週)였고 40%구(區)는 15주(週)까지도 80kg에 도달(到達)치 못하고 있었으며 대조구(對照區)에 비(比)하여 64%의 증체밖에 되지 않었다. 시험사료(試驗飼料)의 소화율(消化率)은 75.2~87.5%였으며 급수율(給水率)은 사료섭취(飼料攝取) 1kg당(當) $1.95-2.01{\ell}$로 되고 있어 사료급여회수(飼料給與回數)는 소화율(消化率)과 급수율(給水率)에 아무런 영향을 주지 않었다.