• 한국가스학회:학술대회논문집
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• 한국가스학회 2000년도 추계학술발표회 논문집
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• pp.148-151
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• 2000

• 멤브레인
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• 제6권3호
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• pp.117-126
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• 1996

Membrane-based gas separation systems are now widely accepted and employed as unit operation in industrial gas, chemical, and allied industries. Following their successful commercialization in the late seventies to recover hydrogen from ammonia purge gas streams, membrane-based systems have gained acceptance in a wide variety of applications. Numerous systems are in operation today to: recover hydrogen from other purge gas and hydrocarbon streams; adjust the $H_{2}/CO$ ratio in syngas; remove $CO_{2}$ from natural gas; recover helium; dry gas streams; and separate air. Lower cost, ease of operation, operational flexibility and portability are a few of the reasons membrane-based systems are chosen over absorption and cryogenic-based separations in certain applications.

• 대한화학회지
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• 제10권1호
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• pp.43-45
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• 1966

The rate of exchange of I atom between alkyl iodides(ethyl or methyl iodide) and $I_2$ in n-hexane have been determined using $II^{131}$. It is found that the escape of $CH_3$ radicals from a solvent cage is faster than $C_2H_5$ radicals and that photolysis of $C_2H_5I$ is almost identical to that in the case of $CH_3I$.

• 대한환경공학회지
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• 제22권10호
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• pp.1825-1832
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• 2000

유류화합물(디젤)로 오염된 불포화층 토양에 대한 현장오존복원공정의 기초연구로, 토양조건에 따른 오존의 이동과 분해, 디젤과의 반응경향을 조사하였다. 건조상태에서 유기물을 제거한 모래와 glass beads 충진컬럼에서 기상 오존의 분해를 조사한 결과 일차반응으로 가정시 반응 속도상수값(k)이 각각 $9.9{\times}10^{-3}s{^{-1}}$와 $4.3{\times}10^{-4}s{^{-1}}$로 나타나 모래의 경우 철 (Fe), 망간(Mn) 성분 등의 촉매작용으로 25배 가량 반감기가 짧은 것을 확인할 수 있었다. 디젤로 오염시킨 현장 토양과 모래를 컬럼에 충진하여 동일조건하에서 오존주입시 토양입자의 크기와 유 무기물의 함량 차에 의한 오존이동상에 지체효과 및 소모량의 차이를 관찰하였고, 50mL/min의 유속에서 공기만을 주입시 DRO(diesel range organic) 기준 초기 디젤총량($800{\pm}50mg/kg$)의 30%가 제거된데 비해 오존을 6mg/min으로 16시간 주입한 결과 각각 80% 이상이 제거되었다. 오존주입시간에 따라 컬럼의 유출 입부에 잔류하는 TPH(total petroleum hydrocarbon)와 DRO 중 aliphatic계열 8개 물질들의 농도를 비교/분석한 결과, 낮은 탄소수 물질들로의 전환과정을 거쳐 유체의 흐름에 따라 컬럼 밖으로 이동됨을 확인하였고, 토양내 수분함량은 오염 토양복원에 오존을 적용시 중요한 인자임을 확인하였다.

• 생명과학회지
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• 제20권11호
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• pp.1648-1655
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• 2010

미더덕 육과 체액을 이용한 천연 조미료의 제조를 위하여 본래의 향과 가열에 따른 변화를 비교해보기 위하여 SDE법과 SPME법으로 미더덕 향기성분을 분석하였다. SDE 추출법으로 얻어진 미더덕 육에 함유된 주요 성분으로서는 hexanal $371.3\;{\mu}g/g$, 1-tridecanol $80.1\;{\mu}g/g$, (Z)-4,5-dimethyhex02-en-4-ol $72.1\;{\mu}g/g$ 등이 있었고, 그 외 다량의 alcohol, aldehydes 및 acids가 얻어졌다. SDE 추출법으로 얻어진 alcohol은 농도도 높았지만 미더덕 육향기성분의 주체가 되는 것으로 나타났다. SPME 추출법으로 얻어진 미더덕 육에는 9종의 alcohols, 1종의 acid, 1종의 aldehyde, 1종의 hydrocarbon, 1종의 ester, 1종의 amine 및 2종의 ketones이 포함되어 있었다. 이들 중 함량이 가장 높았으며 그 중 1-nonanol, 1-decanol 및 1-tridecanol이 주성분이었다. SPME법으로 얻어진 향기성분 중 1-nonanol $31.6\;{\mu}g/g$, (E)-2-butanoic acid dibutylester $20.3\;{\mu}g/g$ 및 heptadecanoic acid $26.7\;{\mu}g/g$으로 전체 향기성분 추출물의 62.1%를 차지하였다. 따라서 SPME법으로 얻어진 향기성분이 SDE법보다 추출효율은 낮았지만 원래 향에 가까운 것으로 나타났다.

• 한국해양공학회지
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• 제26권3호
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• pp.46-54
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• 2012

More than 70% of the accidents that occur on offshore installations stem from hydrocarbon explosions and fires, which, because they involve blast effects and heat, are extremely hazardous and have serious consequences in terms of human health, structural safety, and the surrounding environment. Blast barriers are integral structures in a typical offshore topside module to protect personnel and safety critical equipment by preventing the escalation of events caused by hydrocarbon explosions. Many researchers have shown the adequacy of the simple design tool commonly used by the offshore industry for the analysis and design of blast walls. However, limited information is available for corrugated blast wall design with explosion impact response characteristics. Therefore, this paper presents a parametric study on the explosion impact response characteristics of an offshore installation's stainless steel corrugated blast wall. This paperalso investigates and recommends design parameters for the structural design of a corrugated blast wall based on a nonlinear structural analysis of experiential results.

• Animal cells and systems
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• 제13권3호
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• pp.331-337
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• 2009

Twenty-eight Anopheles species has been so-far identified in Iran, while only 8 species was proved as malaria vector. In this study, we principally examined the cuticular hydrocarbon (CHC) potency in identification of Iranian vectors of malaria and then differentiation of vector and non-vector species of Anopheles. Seven species of malaria vectors and the non-vector species, Anopheles claviger were collected throughout Iran. Female extracts were made out of every five conspecific specimens by surface immersion in pure n-hexane. Each sample was injected into a FID-GC instrument along with the known concentrations of standards. CHC profiles of the eight Anopheles species indicated no qualitative difference. The average mass of each eluted CHC were compared using Repeated ANOVA and Mann-Whitney tests. Results confirmed a significant difference in mass of each single CHC at a specific retention time (RT). Statistical comparison of CHC mass in An. sacharovi, An. stephensi, An. culicifacies and An. fluviatilis at RT 39.6 indicated significant differences (P<0.05) among these species. Analysis of CHC mass of An. dthali, An. superpictus & An. sacharovi at RT 28.5, An. stephensi & An. sacharovi at RT 30.7 and An. sacharovi & An. claviger at RT 30.6 similarly indicated significant differences (P<0.05). An. sacharovi could be distinguished from other species, which showed only trace, by integratable peaks at retention times of 29.7, 31 and 32.6. Similarly, An. claviger could be distinguished from the other species with a trace peak at RT 30.6. In order to separate An. stephensi from the five other species, the integratable peak at RT 30.7 was used. An. dthali could be identified at RT 26.2 by an integratable peak v.s. the trace peaks of other species. An. superpictus had indicator peaks at RTs 27.4 & 28.5 v.s. trace peaks of other species. An. maculipennis with its trace peak at RT 39.6 could be easily differentiated from An. fluviatilis & An. culicifacies. This study proved that all of the examined species of Anopheles could be well identified based on their quantitative differences in CHCs, except for An. fluviatilis & An. culicifacies for which no CHC indicator peak was detected.

• 한국환경과학회지
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• 제17권5호
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• pp.479-484
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• 2008

The application of microwave technology has been investigated in the remediation of diesel-contaminated soil. The paper deals with economic assessment by means of cost analysis and degradation characteristics at different microwave powers for total petroleum hydrocarbon (TPH) in diesel contaminated soils. The soils from S Mountain around the D University were sampled. The samples were screened with 2.0 mm mesh and dried for 6 hours before the diesel was added into the dried soils. The diesel-contaminated soil (3,300 mg THP/kg soil) was prepared with diesel (S Co.). The drying process was carried out in a microwave oven, a standard household appliance with a 2,450 MHz frequency and 700 W of power. The experiments were conducted from 0 to 20 minutes as the microwave powers increased from 350W to 500W to 700W. The concentrations of TPH were analysed using a gas chromatography/mass spectrometer (GC/MS). The initial concentration of TPH was 3,300 mg TPH/kg soil. The weight of contaminated soil was 200g. The concentration of TPH was decreased to 1,828 mg TPH/kg soil (44.7%), 1,347 mg TPH/kg soil (59.2%) and 1,014 mg TPH/kg soil (69.3%) at 350W, 500W and 700W for 15 minutes respectively. In addition, the curve was best fit with first order kinetics using the least-square method. The ranges of a first order rate constant k and r-square were $0.0298{\sim}0.0375min^{-1}$ and $0.9373{\sim}0.9541$ respectively.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.704-715
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• 2006

Oil spill was found in 1999 from a diesel storage facility located near the top of Baekun Mountain in Uiwang City. Application of bioremediation techniques was very relevant in removing oil spills in this site, because the geological condition was not amenable for other onsite remediation techniques. For efficient bioremediation, bacterial communities of the contaminated site and the uncontaminated control site were compared using both molecular and cultivation techniques. Soil bacterial populations were observed to be stimulated to grow in the soils contaminated with diesel hydrocarbon, whereas fungal and actinomycetes populations were decreased by diesel contamination. Most of the dieseldegrading bacteria isolated from contaminated forest soils were strains of Pseudomonas, Ralstonia, and Rhodococcus species. Denaturing gradient gel electrophoresis (DGGE) analysis revealed that the profiles were different among the three contaminated sites, whereas those of the control sites were identical to each other. Analysis of 16S rDNA sequences of dominant isolates and clones showed that the bacterial community was less diverse in the oil-contaminated site than at the control site. Sequence analysis of the alkane hydroxylase genes cloned from soil microbial DNAs indicated that their diversity and distribution were different between the contaminated site and the control site. The results indicated that diesel contamination exerted a strong selection on the indigenous microbial community in the contaminated site, leading to predominance of well-adapted microorganisms in concurrence with decrease of microbial diversity.

• 한국추진공학회지
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• 제12권5호
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• pp.79-91
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• 2008

본 문건은 미 공군 연구소가 미국 방위고등연구계획국의 후원으로 개발한 X-51A 스크램제트 엔진실증기에 대한 비교적 상세한 기술적 내용을 국내에 소개하고자 하는 목적으로 작성되었다. 주된 내용은 Hank 등의 논문을 인용하였으며[1] 기타 관련 문헌을 참고하여 내용을 보완하였다. X-51A는 미 공군의 HyTech 프로그램에 의하여 개발된 탄화수소 연료-냉각 스크램제트 엔진의 비행 시험을 위한 극초음속 시험 비행체로서, 2008년까지 관련 지상 시험을 모두 마치고 2009년에 예정된 비행 시험을 마치면 스크램제트 엔진 및 극초음속 비행 기술은 바야흐로 실용화 단계에 접어들게 될 것이다.