• 제목/요약/키워드: IRA

검색결과 98건 처리시간 0.022초

$NaBH_4$ 수용액 분해 수소 발생용 최적 촉매 개발 (Development of an Catalyst for Hydrolysis of Aqueous Sodium Borohydride Solution)

  • 양태현;;이원용;김창수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.296-298
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    • 2005
  • Hydrogen generation by the hydrolysis of aqueous sodium borohydride $(NaBH_4)$ solutions was studied using IRA-400 anion resin dispersed Pt. Ru catalysts and Lithium Cobalt oxide $(LiCoO_2)$ supported Pt, Ru and PtRu catalysts. The performance of the $LiCoO_2$ supported catalysts is better than the ion exchange resin dispersed catalysts. There is a marked concentration dependence on the performance of the $LiCoO_2$ supported catalysts and the hydrogen generation rate goes down if the borohydride concentration is increased beyond $10\%$. The efficiency of PtRu- $LiCoO_2$ is almost double that of either Ru-$LiCoO_2$ or Pt-$LiCoO_2$ for $NaBH_4$ concentrations up to $10\%$.

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Analysis of capacity management of the intensive care unit in a hospital

  • Kim, Seung-Chul;Horowitz, Ira;Young, Karl K.;Buckley, Thomas A.
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1997년도 추계학술대회발표논문집; 홍익대학교, 서울; 1 Nov. 1997
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    • pp.79-82
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    • 1997
  • A hospital's intensive care unit (ICU) is a limited and critical resource whose efficient utilization of capacity impacts on both the welfare of patients and the hospital's cost effectiveness. Decisions made in the ICU affect the operations of other departments. Yet, decision making in an ICU tends to be mainly subjective and lacking in clear criteria upon which to base any given decision. The study reviews the capacity utilization of one particular ICU, that of a public hospital in Hong Kong, and develops a computer simulation model to improve both the unit's capacity utilization and the quality of care provided to its patients.

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Protoberberine 유도체합성 및 활성연구 (Synthesis of Protoberberine Derivatives and Studies on Their Biological Activities)

  • 이마세;정성현;김동현;정세영;김신규
    • 약학회지
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    • 제34권5호
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    • pp.296-301
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    • 1990
  • Irradiation of the berberinephenolbetaine in a stream of argon produced the 8,14-cycloberberines [1]. On treatment with ethylchloroformate $C_8-N$ bond cleavage of the compound [1] occurred, accompanied with dehydrochlorination to give 7-ethylcarboxyisoquinoline [3], and the product [3] treated with strong alkali solution to give the 13-oxonorotensane [4] in 64% yield. Irradiation of the compound [4] converted easily to dihydro-8H-dibenzo[a, g] quinolizine-8-one [5]. and then the compound [5] was treated with methyliodide to give the 8-oxo-quinolizinium methiode. The intermediate colume chromatography on IRA-400 afforded the benzo[c, g]azecine-5-one[6] in 63% yield. The results of biological activities for these compounds are also presented.

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METHODOLOGICAL ASPECTS OF THE IN VIVO MEASUREMENT OF ILEAL AMINO ACID DIGESTIBILITY IN PIGS - A REVIEW -

  • Yin, Y.-L.;McGracken, Kelvin J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권5호
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    • pp.495-502
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    • 1996
  • Much recent research on protein and amino acid (AA) digestive physiology of pigs has been concerned with measurement of the ileal apparent and true digestion and absorption. For measurement of the ileal apparent digestibility of AA, the steered ileo-caecal valve cannulation (SICV) and the ileo-rectal anastomosis (IRA) techniques appear to be the more reliable and simple methods, when compared with any methods requiring use of a marker for calculation of digestibility, or with the complex techniques of ileo-caecal re-entrant cannula (ICRC) and the postvalve ileo-colic re-entrant cannula (IPVC). On the other hand, the peptide alimentation ultrafiltration methods might be a better choice for measurement of the ileal endogenous nitrogen (N) and AA flow in a routine feedstuff analysis, although the classical method of $^{15}N-isotope$ dilution method is still a standard method for N and AA nutrition research in pigs.

비선형 천해파의 스펙트라 (Spectra of nonlinear shallow water waves)

  • 나르시세자히보;이라디덴쿠로바;에핌페리높스키
    • 한국해안해양공학회지
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    • 제19권4호
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    • pp.355-360
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    • 2007
  • 본 논문에서는 수심이 일정한 수조에서의 비선형 천해파의 변형 과정에 대한 연구를 수행하였다. 파랑의 최초 쇄파에 대한 특성을 자세히 분석하고, 비선형파의 경사 및 퓨리에 스펙트럼을 산정하였다. 분석결과 스펙트럼의 진폭은 실용적으로 추산이 가능한 파랑 경사를 이용하여 표현할 수 있다.

용액의 성분 및 농도에 따른 이온교환 특성 연구 (A Study on Ion Exchange Characteristics with Composition and Concentration of Solution)

  • 정현준;안현경;이인형
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2006년도 춘계학술발표논문집
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    • pp.599-601
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    • 2006
  • 본 논문에서는 용액의 농도가 이온교환 특성에 미치는 영향을 조사하기 위하여 농도는 $Na^+\;50$, 125, 250ppm, $Cl^-\;165$, 315, 610ppm, 입자성 물질의 유입 농도 0ppm, 유속 500ml/min, 이온교환 수지는 ROHM&HAAS IR 120 양이온 수지와 ROHM&HAAS IRA 402 음이온 수지를 사용하였다. 수지탑 배열은 혼상-혼상-음이온 수지탑 순으로, 이온교환 수지탑의 양 음이온교환 수지의 조성 비율은 1:2 로 실험한 결과 이온교환 수지탑 성능은 유입 용액 성분 및 농도에 영향을 받는 것으로 나타났다. 이온교환 수지탑 배열 순서에 따라 파과시점이 연장되며, 파과순서는 음이온의 경우 $Cl^-\;<\;NO_3\;^-\;<\;F^-$, 양이온의 경우 $Na^+\;<\;K^+\;<\;Ca^{2+}$ 순 이였으며, 용액의 농도가 증가할수록 파과시간이 단축되었다.

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미생물에 의한 핵산관련물질의 생산에 관한 연구 2 (Studies on Production of Nucieic acid Derivatives by Microorganisms(II))

  • 배무;이계준
    • 미생물학회지
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    • 제10권3호
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    • pp.109-116
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    • 1972
  • Three strains among 120 adenineless mutants of Brevibacterium ammoniagenes described in the previous paper were screened out to accumulate UV absorbing substances in the culture broth. It was analyzed to be 5'-inosinic acid and hypoxanthine by means of two dimensional paper chromatography, UV absorption spectra and periodate oxidation. 5'-IMP was isolated from the culture broth of the mutant No. 203 with anion-exchange resin amberite IRA-400 and recrystallized from ethanol. It was proved identical to authentic sample by Infra-red absorption spectrum. The growth responses of the mutant No. 2013 were demonstrated to require adenine, but not with adenosine and 5'-AMP.

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Photoinduced Electron Transfer Reactions of Aryl Benzyl Sulfides Promoted by 2,4,6-Triphenylpyrilium Tetrafluoroborate (TP+BF4-)

  • Memarian, Hamid Reza;Ira, Mohammadpoor Baltork;Bahrami, Kiumars
    • Bulletin of the Korean Chemical Society
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    • 제27권1호
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    • pp.106-110
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    • 2006
  • Photocatalytic electron transfer reactions of aryl benzyl sulfides using 2,4,6 triphenylpyrilium tetrafluoroborate ($TP^+BF_4^-$) resulted in the oxidation of these sulfides to the corresponding sulfoxides and also in most cases in the C-S bond cleavage of them along with formation of aromatic aldehydes. In these reactions, the formation of sulfide radical cation has been proposed, which undergoes either oxidation to the corresponding sulfoxide or C-S bond cleavage to the formation of aromatic aldehydes. The further oxidation of sulfoxides to sulfones has not been observed. The influence of substrate structures on the reaction pathways as well as the role of $O_2$ in this respect is discussed.

섬유성 바이오매스를 이용한 Acetic Acid 생산 (Production of Acetic Acid from Cellulosic Biomass)

  • 우창호;박준호;윤현희
    • KSBB Journal
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    • 제15권5호
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    • pp.458-463
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    • 2000
  • Production of acetic acid from cellulosic biomass by Simultaneous Saccharification and Extractive Fermentation (SSEF) was investigated. The homoacetate organism used in this study was a strain of Clostridium thermoaceticum, ATCC # 49707. A batch operation of Simultaneous Saccharification and Fermentation(SSF) using ${\alpha}$-cellulose at pH 5.5 and 55$^{\circ}C$ yielded 40% conversion of cellulose to acetic acid, while a fed-batch SSF operation produced a maximum acetic acid concentration of 25 g/L, with 50% overall yield. In-situ extractive fermentation to reduce the end-product inhibition on both bacteria and enzyme was carried out. in a batch SSEF using 200 g/L IRA-400 resin, acetic acid concentration reached to 23.9 g/L and acetic acid yield and productivity were observed to be 48% and 0.20 g/L-hr, respectively.

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The Impacts of Climate Variability on Household Consumption: Evidence Based on Village Weather Data in Indonesia

  • Pratiwi Ira Eka;Bokyeong Park
    • East Asian Economic Review
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    • 제27권4호
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    • pp.273-301
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    • 2023
  • This study investigates the impacts of long-term climate variability on household consumption in Indonesia, a country highly vulnerable to climate change. The analysis combines household survey data from nearly 5,998 families with satellite-derived weather data from NASA POWER spanning 30 years. We use the long-term variability in temperature and precipitation as a proxy for climate change. This study examines the impact of climate change which proceeds over the long term, unlike previous studies concerning one-off or short-term climate events. In addition, using satellite data enhances the accuracy of households' exposure to climate variability. The analysis finds that households in a village with higher temperature and precipitation variability significantly consume less food. This implies that households more exposed to climate change are at higher risk of malnutrition in developing countries. This study has a limitation that it cannot rule out the potential endogeneity of choosing a climate-vulnerable residential location due to economic poorness.