• 제목/요약/키워드: extractive

검색결과 230건 처리시간 0.032초

자연어메니티가 인구 변화에 미치는 영향에 관한 연구 (Relation of the Natural Amenity and Population Change)

  • 박미정;정남수;장민원;이정재
    • 농촌계획
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    • 제14권4호
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    • pp.1-9
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    • 2008
  • Many urban people are attracted to the recreational opportunities and attractions of rural areas, such as beautiful scenery, lakes, mountains, forests, and resorts. Furthermore, rural development planning increasingly emphasizes the integration of resource extractive industries with non-market-based recreational and amenity values. This article outlines a method to estimate an amenity level of rural areas such as natural amenities index and shows the relation of the natural amenity and population growth. The results revealed that natural amenity classifying each region can be explained with geographical characteristics, temperature-humidity, and sunshine duration time. In analysis with population, natural amenity does not exactly explain that but can be one of the important factor of population change.

Improvement of Hydrocarbon Recovery by Two-Stage Cell-Recycle Extraction in the Cultivation of Botryococcus braunii

  • An, Jin-Young;Sim, Sang-Jun;Kim, Byung-Woo;Lee, Jin-Suk
    • Journal of Microbiology and Biotechnology
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    • 제14권5호
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    • pp.932-937
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    • 2004
  • In situ extraction by organic solvent was studied in order to improve the recovery yield of hydrocarbon from the culture of Botryococcus braunii, a green colonial microalga. When the solvent mixture of octanol as an extractive solvent and n-octane as a biocompatible solvent was added to a two-phase column, the algal growth was seriously inhibited, even at a low concentration of polar octanol. Therefore, a two-stage cell-recycle extraction process was proposed to improve the contact area between the organic phase and the aqueous phase. The hydrocarbon recovery with in situ cell-recycle extraction showed a three-fold increase (57% of cell) in yield over that with two-phase extraction. In addition, over 60% of the hydrocarbon could be recovered without serious cell damage by downstream separation when this process was applied to the culture broth after batch fermentation.

초저황 디젤 생산을 위한 탈황 기술 동향 (Review of Desulfurization Technology for Ultra Low Sulfur Diesel Production)

  • 박조용;김재곤;임의순;정충섭
    • 한국응용과학기술학회지
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    • 제30권3호
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    • pp.431-443
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    • 2013
  • Sulfur content of diesel fuel has been cut down to under 10 ppm ULSD (ultra low sulfur diesel) level by environmental regulation with the aim of reducing exhaust emissions. This review discusses the methods and principles of sulfur reduction in diesel and presents an overview of new approaches for ultra-deep desulfurization. The deep HDS (hydrodesulfurization) problems of diesel streams is exacerbated by the inhibiting effect of co-existing aromatics, nitrogen compounds and $H_2S$. The new approaches to deep desulfurization includes non-HDS type processing schemes such as adsorptive, extractive and oxidative desulfurization.

Simultaneous Profiling Analysis of Urinary Organic Acids and Amino Acids by Gas Chromatography and Gas Chromatography-Mass Spectrometry for Biochemical Diagnosis of Inherited Metabolic Disorders

  • Paik, Man-Jeong;Lee, Yoon-Suk;Lee, Hong-Jin;Kim, Sook-Za;Kim, Kyoung-Rae
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.234.2-235
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    • 2002
  • An efficient method for the simultaneous profiling analysis of organic acids and amino acids combined with a simple graphic pattern recognition method was developed for more objective diagnosis of organic acidurias and amino acidurias. In this method, extractive ethoxycarbonly (EOC) reaction of amino and sufhydry groups with ethyl chloroformate was followed by methodime (MO) formation of carbonyl group in aqueous solution (omitted)

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저분자 유기산을 이용한 폐금속광산 주변토양 정화 (Remediation of Soil Surrounding Abandoned Metal Mine By Using Low Molecular Weight Organic Acid)

  • 이동호;박옥현
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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    • pp.183-188
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    • 1998
  • The efficiency of removing cadmium, copper, and lead from a contaminated soil of abandoned metal mine was studied in a laboratory investigation where citric acid were used to extract the metal from the soil. The contamination level of Pb, Cu in the soil A were 875.5, 667.5mg/kg respectively. The mobility and bioavailability of the metals in soil were also estimated by Sequential Chemical Extractions. Citric acid were examined for its potential extractive capabilities. Concentrations of the acid examined in this study ranged from 0.025 to 0.15M. The pH of the suspensions and S/S ratio in which the extractions were performed ranged from 2.4 to 8.1, and from 2.1:1 to 20:1. Results showed that the removal of contaminant using citric acid was pH and S/S raton dependent.

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도토리에서 분리한 Dotorioside I, II의 구조 (Structures of Dotorioside I and II Obtained from the Fruits of Quercus acutissima $C_{ARRUTHERS}$)

  • 임광식;손미정;이시강
    • 약학회지
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    • 제38권3호
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    • pp.223-229
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    • 1994
  • From the methanolic extractive of the fruits of Quercus acutissima $C_{ARRUTHERS}$(Fagaceae) a mixture(QC-A saponin) of two ester glycosides, which were named as dotorioside I(3) and ll(4), was separated by silica gel column chromatography and HPLC. The structures of these two glycosides including their genuine aglycones(1,2) were elucidated as 1: $2{\alpha}$, $3{\beta}$, $19{\alpha}$, 23-tetrahydroxyolean-12-en-28-oic acid, 2: $2{\alpha}$, $3{\beta}$, $19{\alpha}$, 23-tetrahydroxyurs-12-en-28-oci acid, 3: 28-O-${\beta}$-D-glucopyranosyl ester of 1, 4: 28-O-${\beta}$-D-glucopyranosyl ester of 2, respectively, on the basis of chemical and spectral evidence.

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Pharmacognostic Evaluation of the Roots of Berberis tinctoria Lesch

  • Rawat, Ajay Kumar Singh;Srivastava, Sharad Kumar
    • Natural Product Sciences
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    • 제13권1호
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    • pp.27-32
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    • 2007
  • Berberis tinctoria (Berberidaceae), commonly known as Nilgiri Barberry is a common allied species to B. aristata, used in India Traditional Systems of Medicine by the name of 'Daruharidra' for skin disease, jaundice, affection of eyes, and rheumatism. Keeping this in view, in the present study attempts have been made to identify marker characters of B. tinctoria. Some of the diagnostic features of the root are patches of pericyclic fibre, pitted sclerieds, crystals, berberine containing cells and heterocyclic medullary rays. Besides, the physicochemical characters such as total ash; acid insoluble ash; alcohol and water soluble extractive; tannins; sugar and starch percentages has also shown some variations. The percentage of berberine as berberine hydrochloride was also calculated through HPTLC densitometric method and it was found almost similar to B. aristata, B. asiatica and B. chitria i.e. 3.36%. Thus it can be explored as a possible source of substitute to B.aristata.

Mono-layer Compositional Analysis of Surface of Mineral Grains by Time-of-Flight Secondary-Ion Mass Spectrometry (TOF-SIMS).

  • 김주영;;공봉성
    • 한국광물학회:학술대회논문집
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    • 한국광물학회.한국암석학회 2005년도 공동학술발표회 논문집
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    • pp.50-57
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    • 2005
  • Although the bulk composition of materials is one of the major considerations in extractive metallurgy and environmental science, surface composition and topography (edges and dislocations are preferred sites for physicochemical reactions) control surface reactivity, and consequently play a major role in determining metallurgical phenomena and pollution by heavy metals and organics. An understanding of interaction mechanisms of different chemical species with the mineral surface in an aqueous media is very important in natural environment and metallurgical processing. X-ray photoelectron spectroscopy (XPS) has been used as an ex-situ analytical technique, but the material to be analyzed can be any size from $100{\mu}m$ up to about 1 cm. It can also measure mixed solids powders, but it is impossible to ascertain the original source of resulting x-ray signals where they were emitted from, since it radiates and scans the macro sample surface area.

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천련자 추출물이 간기능(肝機能)에 미치는 영향(影響)(I) -천련자의 분획이 약물대사효소계 및 담즙분비에 미치는 영향- (The Effects of Meliae toosendan Fructus on Liver Function (I) -Effects of Each Fractions from Meliae toosendan Fructus on Drug Metabolism Enzyme System and Bile Secretion-)

  • 김부생;최종원;이정규
    • 생약학회지
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    • 제24권1호
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    • pp.63-68
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    • 1993
  • Meliae toosendan Fructus is the fruit of Melia toosendan $S_{IEB}$. et $Z_{UCC}$. (Meliaceae), which is written in oriental terminology as clearing heat and drying dampness, and also explained using liver, stomach and small intestine for channels entered. Among the five fractions prepared from methanol whole extractive of the herb, the chloroform fraction which suggests the presence of triterpenoid, flavonoid and alkaloid stimulated the activities of drug metabolizing enzymes and bile secretion and lowered the serum transaminase activities of liver damaged by carbon tetrachloride.

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