• Title/Summary/Keyword: High conversion

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Arterial Switch Operation in Patients with Intramural Coronary Artery: Early and Mid-term Results

  • Kim, Hyung-Tae;Sung, Si-Chan;Kim, Si-Ho;Chang, Yun-Hee;Ahn, Hyo-Yeong;Lee, Hyoung-Doo
    • Journal of Chest Surgery
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    • v.44 no.2
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    • pp.115-122
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    • 2011
  • Background: The intramural coronary artery has been known as a risk factor for early death after an arterial switch operation (ASO). We reviewed the morphological characteristics and evaluated the early and mid-term results of ASO for patients with an intramural coronary artery. Materials and Methods: From March 1994 to September 15th 2010, 158 patients underwent ASO at Dong-A and Pusan National University Hospitals for repair of transposition of the great arteries and double outlet right ventricle. Among these patients, 14 patients (8.9%) had an intramural coronary artery. Mean age at operation was $13.4{\pm}10.2$ days (4 to 39 days) and mean body weight was $3.48{\pm}0.33$ kg (2.88 to 3.88 kg). All patients except one were male. Eight patients had TGA/IVS and 4 patients had an aortic arch anomaly. Two patients (14.3%) had side-by-side great artery relation, of whom one had an intramural right coronary artery and the other had an intramural left anterior descending coronary artery. Twelve patients had anterior-posterior relation, all of whom had an intramural left coronary artery (LCA). The aortocoronary flap technique was used in coronary transfer in 8 patients, of whom one patient required a switch to the individual coronary button technique 2 days after operation because of myocardial ischemia. An individual coronary button implantation technique was adopted in 6, of whom 2 patients required left subclavian artery free graft to LCA during the same operation due to LCA injury during coronary button mobilization and LCA torsion. Results: There was 1 operative death (7.1%), which occurred in the first patient in our series. This patient underwent an aortocoronary flap procedure for coronary transfer combining aortic arch repair. Overall operative mortality for 144 patients without an intramural coronary artery was 13.2% (19/144). There was no statistical difference in operative mortality between the patients with and without an intramural coronary artery (p>0.1). There was no late death. The mean follow-up duration was $52.1{\pm}43.0$ months (0.5 to 132 months). One patient who had a subclavian artery free graft required LCA stenting 6.5 years after surgery for LCA anastomotic site stenosis. No other surviving patient needed any intervention for coronary problems. All patients had normal ventricular function at latest echocardiography and were in NYHA class 1. Conclusion: The arterial switch operation in Transposition of Great Arteries or Double Outlet Right Ventricle patients with intramural coronary can be performed with low mortality; however, there is a high incidence of intraoperative or postoperative coronary problems, which can be managed with conversion to the individual coronary button technique and a bypass procedure using a left subclavian free graft. Both aortocoronary flap and individual coronary button implantation techniques for coronary transfer have excellent mid-term results.

Optimization of Interesterification Reaction for the Continuous Production of trans-Free Fat in a Packed Bed Enzyme Bioreactor with Immobilized Lipase (고정화 리파제를 이용한 충진형 효소생물반응기 내에서의 무-트랜스 유지 연속 생산을 위한 에스테르 교환 반응의 최적화)

  • Kim, Sang-Woo;Park, Kyung-Min;Ha, Jae-Uk;Lee, Jae-Hwan;Chang, Pahn-Shick
    • Korean Journal of Food Science and Technology
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    • v.41 no.2
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    • pp.173-178
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    • 2009
  • Epidemiological studies showed that high trans-fat consumption is closely associated with getting the risks of cardiovascular disease. The objective of this study was to produce trans-free fat through lipase-catalyzed interesterification, as a substitute for the cream margarine commonly used in industry. Optimum conditions for interesterification in a packed bed enzyme bioreactor (PBEB) were determined using response surface methodology (RSM) based on central composite design. Three kinds of reaction variables were chosen, such as substrate flow rate (0.4-1.2 mL/min), reaction temperature (60-70$^{\circ}C$), and ratio of fully hydrogenated canola oil (FHCO, 35-45%) to evaluate their effects on the degree of interesterification. Optimum conditions from the standpoint of solid fat content (SFC) were found to be as follows: 0.4 mL/min flow rate, 64.7$^{\circ}C$ reaction temperate, and 42.8% (w/w) ratio of FHCO, respectively. The half-life of immobilized lipase in PBEB with two stages at 60$^{\circ}C$ ($1^{st}$ stage) and 55$^{\circ}C$ ($2^{nd}$ stage) was about more than 30 days as estimated by extrapolating the incubation time course of tristearoyl glycerol (TS) conversion, whereas the half-life of the enzyme in PBEB with single stage at 65$^{\circ}C$ was only about 15 days. Finally, the results from SFC analysis suggest that trans-free fat produced in this study seems to be a suitable substitute for the cream margarine commonly used in industry.

Survey on the Using Frequency of Processed Foods and Dietician' Perception against Management of Food Service at Food Service Institutions (집단급식소의 가공식품 이용 실태 및 급식관리에 대한 영양사의 인식에 대한 조사)

  • Soh, Gowan-Soon;Kim, Yong-Suk;Shin, Dong-Hwa
    • Journal of Food Hygiene and Safety
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    • v.22 no.1
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    • pp.29-36
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    • 2007
  • The using frequency of processed foods and dietician's perception against management of food service at 98 food service institutions located in Jeollabuk-Do were surveyed. Food service institutions included 13 hospitals,38 schools,40 enterprises, and 7 others. Single menu (75.5%) with two (33.7%) or three (57.1%) side dish was offered. In addition, the offering ratio of boiled water and spring water was 37.8 and 32.7%, respectively. The processed foods with high using frequency were kochujang (1.19), sesame oil (1.22), and doenjang (1.30), but that of leek, onion, Chinese cabbage, and radish were 4.95, 4.62, 4.60, and 4.26, respectively. Dietician's major affairs in all type of food service institutions were cooking (64.3%), purchase (48.0%), and personnel managements (39.8%). Dieticians, however, had a low perception against safety and nutrition management. Therefore, in order to prevent the outbreak of food-borne diseases, we estimated that the education and the conversion of dietician' perception against safety and nutrition management were needed.

Characterization of Pretreatment for Barley straw by Alkaline Solutions (염기 용매를 이용한 보릿짚의 전처리 특성)

  • Kim, Kyoung-Seob;Kim, Jun Seok
    • Korean Chemical Engineering Research
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    • v.50 no.1
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    • pp.18-24
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    • 2012
  • Lignocellulose is difficult to hydrolyze due to the presence of lignin and the technology developed for cellulose fermentation to ethanol is not yet economically viable. However, recent advances in the extremely new field of biotechnology for the ethanol production are making it possible to use of Agriculture residual biomass, e.q., Barley straw, because of their several superior aspects as Agriculture residual biomass; low lignin, high contents of carbohydrates. Barley straw consists of 39.78% cellulose (glucose), 22.56% hemicelluloses and 19.27% lignin. Pretreatment of barley straw using NaOH pretreatment solutions concentration with 2%, temperature $85^{\circ}C$ and reaction times 1 hr were investigates. $NH_4OH$ pretreatment condition was solutions concentration with 15%, temperature $60^{\circ}C$, and reaction times 24hr were investigates. Furthermore, enzymatic saccharification using cellulose at $50^{\circ}C$, pH 4.8, 180 rpm for conversion of cellulose contained in barley straw to monomeric sugar. The pretreatment of barley straw using NaOH and $NH_4OH$ can significantly improve enzymatic saccharification of barley straw by extract more lignin and increasing its accessibility to hydrolytic enzymes. The result showed NaOH pretreatment extracted yield of lignin was 24.15%. $NH_4OH$ pretreatment extracted yield of lignin was 29.09%. Shaccharification of barley straw pretreatment by NaOH for 72hr and pH 4.8 result in maximum glucose concentration 15.39g/L (58.40%) and by $NH_4OH$ for 72hr and pH 4.8 result in maximum glucose concentration 16.01g/L (64.78%).

Effect of Steam-Treated Zeolite BEA Catalyst in NH3-SCR Reaction (NH3-SCR 반응에서 스팀 처리된 zeolite BEA 촉매의 영향)

  • Park, Ji Hye;Cho, Gwang Hee;Hwang, Ra Hyun;Baek, Jeong Hun;Yi, Kwang Bok
    • Clean Technology
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    • v.26 no.2
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    • pp.145-150
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    • 2020
  • Nitrous oxide (N2O) is one of the six greenhouse gases, and it is essential to reduce N2O by showing a global warming potential (GWP) equivalent to 310 times that of carbon dioxide (CO2). Selective catalytic reduction (SCR) is a technology that converts ammonia into harmless N2 and H2O by using ammonia as a reducing agent to remove NOx, one of the air pollutants; the process also produces high denitrification efficiency. In this study, the Fe-BEA catalyst was steam-treated at 100 ℃ for 2 h before Fe ion exchange in the fixed bed reactor in order to investigate the effect of the steam-treated Fe-BEA catalyst on the NH3-SCR reaction. NH3-SCR reaction test of synthesized catalysts was performed at WHSV = 180 h-1, 370 to 400 ℃ in the fixed bed reactor. The Fe-BEA(100) catalyst steam-treated at 100 ℃ showed a somewhat higher activity than the Fe-BEA catalyst at 370 to 390 ℃. The catalysts were characterized by BET, ICP, NH3-TPD, H2-TPR, and 27Al MAS NMR in order to determine the cause affecting NH3-SCR activity. The H2-TPR result confirmed that the Fe-BEA(100) catalyst had a higher reduction of isolated Fe3+ than the Fe-BEA catalyst, and that the steam treatment increased the amount of isolated Fe3+ as an active species, thus increasing the activity.

Effect of Feeding Thymus vulgaris Powder on the Productivity, Egg Quality and Egg Yolk Fatty Acid Composition in Laying Hens (Thymus vulgaris 분말의 급여가 산란계의 생산능력, 난품질 및 난황 내 지방산 조성에 미치는 영향)

  • Park, Seong-Bok;Lee, Kyeong-Jin;Lee, Wang-Hyu;Ryu, Kyeong-Seon
    • Korean Journal of Poultry Science
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    • v.39 no.2
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    • pp.157-161
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    • 2012
  • The objective of this study was to evaluate the effects of feeding dried Thymus vulgaris powder (TVP) on the layer performance, egg quality and egg yolk fatty acid composition. Two hundred eighty eight, 35 weeks old Brown nicks were allocated in the cage for five TVP (0, 0.25, 0.5, 1.0 and 2.0%) diets with four replicates in each treatment. Each basal diet contained 16.0% CP and 2,800 kcal/kg ME and supplied to layers for 8 weeks. Egg production and egg weight were not statistically different but numerically increased in birds fed 2.0% TVP than other treatments. Egg mass was not consistent depending on the TVP addition levels in diets. Feed intake was significantly lower in TVP addition treatments than the control (p<0.05), however, feed conversion was not significantly differed among control and treatments (p<0.05). Dietary addition of 2.0% TVP showed high values on albumin height, Haugh unit and egg yolk color and they are 7.93, 86.79 and 7.20, respectively (p<0.05). Palmitic and arachidonic acids were remarkably lowered when 2.0% TVP added to basal diets and then fed to birds for 8 weeks, in contrast, significantly higher linolenic acid composition was determined in birds fed 2.0% TVP (p<0.05). As the results, the highest unsaturated fatty composition and UFA/SFA ratio were observed in 2.0% TVP treatment as compared to those of control and other treatments. Therefore, the results indicate that the Thymus vulgaris powder addition to basal diet tended to have positive effects on egg quality and egg yolk fatty acids composition, and the optimum addition of Thymus vulgaris powder may be 2.0%.

Performance of Growing Period of Large-Type Korean Native Ducks (토종오리 대형종의 육성기 능력)

  • Hong, Eui-Chul;Choo, Hyo-Jun;Kang, Bo-Seok;Kim, Chong-Dae;Heo, Kang-Nyeong;Lee, Myeong-Ji;HwangBo, Jong;Suh, Ok-Suk;Choi, Hee-Cheol;Kim, Hak-Kyu
    • Korean Journal of Poultry Science
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    • v.39 no.2
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    • pp.143-149
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    • 2012
  • This work was carried out to investigate the performance of growing period of large-type Korean native ducks. A total of four hundred twenty female and male duck chicks generated from A and B strains of ducks. Groups were four crossbreds (3 replications/crossbred, 35 birds/replication) as $2{\times}2$ factors (2 strains, A and B; 2 genders, female and male). On the body weight, male of B strains was the highest among 4 treatments after the age of 4 week (P<0.05). Body weight of B strain was higher than that of A strain at all period (P<0.05). Body weight of male was higher compared to that of female after the age of 4 week (P<0.05). On the body weight gain, male of B strain was the highest and female of A strain was the lowest among 4 treatments at 0~8, 0~12, 0~16 and 0~20 weeks (P<0.05). Body weight gain of male was higher than that of female after the age of 4 week (P<0.05). On the feed intake, male of B strain was the highest among 4 treatments from the age of 0 week and to the age of 4, 12, 16 and 20 week (P<0.05). Feed intake of male was higher than that of female at 0~12, 0~16 and 0~20 weeks (P<0.05). On the feed conversion ratio, male of B strain was the highest among other treatments 0~4 weeks and female of A strain was at 0~8 and 0~12 weeks (P<0.05). Feed intake of female was higher compared to that of female at 0~8 weeks and male was high at 0~20 weeks. These results provided the basic data on the record of growing phase of large-type Korean native ducks.

Effects of Corn Distiller's Dried Grains with Solubles on Production Performance in Laying Hens (옥수수주정박의 급여가 산란계 생산성에 미치는 효과)

  • Cheon, Yeoung-Ju;Lee, Hak-Lim;Shin, Myung-Ho;Lee, Soo-Kee;Lee, Bong-Duk;Son, Chan-Ku
    • Korean Journal of Agricultural Science
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    • v.34 no.1
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    • pp.53-60
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    • 2007
  • A layer feeding trial was conducted for 10 weeks to investigate the effects of the addition of corn distillers dried grains with solubles (DDGS) to layer diets on the laying performance, egg qualities, and yolk fatty acid composition. Nine hundred Hyline Brown layers, 24 weeks of age,were randomly allotted to 20 replicate laying cages, 45 birds per replicate. There were four diet treatments (0, 10, 15, and 20% DDGS), and five replicates per treatment. All experimental diets were prepared to contain iso-protein (17%) and iso-calorie (TMEn 2,780 kcal/kg). The use of DDGS up to 20% level in layer diets did not exert any influence on feed intake, laying rate, total egg mass, mean egg weight, and feed conversion ratio. DDGS did not exert any influence in weight of egg, breaking strength, and color of eggshell. The albumen height and Haugh unit was not influenced by DDGS addition. The yolk color was significantly increased by DDGS supplementation. As the DDGS level increased, the oleic acid content decreased, and the linoleic acid increased (P<0.05). The degree of saturation of yolk fatty acids was not affected by dietary DDGS. The inclusion of DDGS up to 20% in layer diets resulted in the decrease of feed cost per kg without any effect in the laying performance. In conclusion, the use of DDGS up to 20% level in layer diets could replace corn and soybean meal without any harmful effect on the laying performances.

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Characteristics of Corrosion and Water Quality in Simulated Reclaimed Water Distribution Pipelines (모형 재이용관을 이용한 하수재이용수의 부식 및 수질영향 연구)

  • Kang, Sung-Won;Lee, Jai-Young;Lee, Hyun-Dong;Kim, Gi-Eun;Kwak, Pill-Jae
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.7
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    • pp.473-479
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    • 2012
  • Water reuse has been highlighted as a representative alternative to solve the lacking water resource. This study carried out a study on the pipe corrosion and water quality change which can occur through the supply of reclaimed water, using a simulated reclaimed water distribution pipeline. Galvanized steel pipe (GSP), cast iron pipe (CIP), stainless steel pipe (STSP) and PVC pipe (PVCP) were used for the pipe materials. Reclaimed water(RW) and tap water(TW) were respectively supplied into simulated reclaimed water distribution pipelines. As a result of performing a loop test to supply reclaimed water to simulated reclaimed water distribution pipelines, the weight reduction of pipe coupons showed the sequence of CIP > GSP > STSP ${\approx}$ PVCP. In addition, reclaimed water showed a high corrosion rate comparing to that of tap water. In case of CIP, the initial corrosion rate showed 3.511 mdd(milligrams per square decimeter per day) for reclaimed water and 2.064 mdd for tap water and the corrosion rate for 90 days showed 0.833 mdd for reclaimed water and 0.294 mdd for tap water. Also in case of GSP, the initial corrosion rate showed 2.703 mdd for reclaimed water and 2.499 mdd for tap water and the corrosion rate for 90 days showed 0.349 mdd for reclaimed water and 0.248 mdd for tap water, which was a tendency similar to that appeared in CIP with a tendency to reduce the corrosion rate. As a result of water quality changes of reclaimed water at pipe materials to carry out the loop test, there was higher conversion ratio of ammonia into nitrate in CIP and GSP with higher corrosion rate than that in STSP and PVCP where no corrosion has occurred. The highest denitrification rate of nitrate could be observed from CIP with the most particles generated from corrosion. In CIP, it could be confirmed that there was MIC (Microbiologically Induced Corrosion) as a result of EDS (Energy Dispersive X-ray spectrometer System) analysis results.

Electrochemical Characteristics of Transition Metal Pyrophosphate as Negative Electrode Materials through Solid-state Reaction (고상법으로 합성된 리튬이온 이차전지용 음극물질로서 전이금속 피로인산화물의 전기화학적 특성)

  • Hong, Min Young;An, Sang-Jo;Ryu, Ji Heon
    • Journal of the Korean Electrochemical Society
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    • v.23 no.4
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    • pp.105-112
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    • 2020
  • Transition metal oxide, which undergoes a conversion reaction in the negative electrode material for a lithium-ion batteries, has a high specific capacity, but still has several critical problems. In this study, manganese pyrophosphate (Mn2P2O7), nickel pyrophosphate (Ni2P2O7), and carbon composite materials with pyrophosphates as novel negative electrode materials instead of transition metal oxide, are synthesized through simple solid-state reaction. The initial reversible capacity of Mn2P2O7 and Ni2P2O7 are 333 and 340 mAh g-1, and when the composite materials are composed with carbon, the reversible capacity increases to 433 and 387 mAh g-1, respectively. The initial Coulombic efficiency is also improved by about 10%. The Mn2P2O7 and carbon composite material has the highest initial capacity and efficiency, and has the best cycle performance. Mn2P2O7 containing polyanion, has a lower specific capacity due to the large mass of polyanion compared to MnO (manganese oxide). However, since Mn2P2O7 shows a voltage curve with a slope, the charging (lithiation) voltage increases from 0.51 to 0.57 V (vs. Li/Li+), and the discharge (delithiation) voltage decreases from 1.15 to 1.01 V (vs. Li/Li+). Therefore, the voltage efficiency of the cell is improved because the voltage difference between charging and discharging is greatly reduced from 0.64 to 0.44 V, and the operating voltage of the full cell increases because the negative electrode potential is lowered during the discharging process.