• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.443-444
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• 1999

악취는 냄새를 유발하는 기체상 물질이 사람의 후각을 자극하여 불쾌감이나 혐오감을 주는 상태를 말한다. 악취물질은 정유공장, 화학공장, 하수처리장, 분뇨 및 축산 폐수처리장, 매립장 등의 다양한 발생원이 있으며, 여러가지 복합된 화합물이 원인이 되어 악취를 유발한다. 단위 물질로서 황화수소(H$_2$S)는 계란 썩는 냄새, 메르캅탄(mercaptan)류는 야채 썩는 냄새, 아민류는 생선냄새 등의 특이한 냄새를 유발하며, 최저 감지값은 물질별로 상당한 차이를 나타내고 있다(이광묵, 1993).(중략)

• Membrane Journal
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• v.2 no.2
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• pp.112-121
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• 1992

최근 십여년동안 자원, 에너지, 환경의 모든 면에서 기능성막의 역할이 증대해짐에 따라 기능성막에 대해 큰 관심이 모아지고 있다. 기존하는 기능성막의 소재면에서 볼 때 고분자막(고체막), 액체막으로 대별할 수 있으며, 이들의 경우 해수의 담수화, 원료 및 제품의 분리, 농축, 정제, 회수공정 또한 석유화학분야에서 고효율$\cdot$고선택성 기체혼합물 분리, 산업용 폐수처리분야 뿐 만 아니라, 태양에너지의 효과적인 이용, 전도성, 감광성, 광학특성막 등을 이용한 각종 센서제조 등 실로 광범위한 분야에서 응용되어지고 있다. 기능성막의 관점에서 볼 때, 고기능$\cdot$고효율$\cdot$고선택성을 가지는 막은 생태계에 존재하는 생체막이 가장 이상적이라 할 수 있다.

• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.25-32
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• 2010

Contamination of soil and groundwater by the compounds of hydrocarbon petroleum has been widely accepted as the main cause that harms the environments and health. To remove those pollutants, absorbing clothes, activated carbons, or oil-water separation devices with the gravity method are employed for treatment. However, those materials and devices cannot remove the emulsion pollutants despite of their efficiency for removing free products. Therefore, we investigated the problems which occur during the groundwater treatment for the highly concentrated suspended solid particles, which can be resulted from excavation, and to propose methods to remove TPH(Total Petroleum Hydrocarbon). After coagulation experiment with high molecular polymers, the concentration of SS(Suspended Solids) and COD(Chemical Oxygen Demand) turned to satisfy the groundwater quality criteria within 5 minutes while the concentration of TPH failed to meet the water quality standard of effluent. Consequently, the water quality criteria for effluent could not be met by single DAF(Dissolved Air Flotation) process. However all water quality criteria could be satisfied after 20 minutes when coagulation reactions are carried out simultaneously in the DAF reactor.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.79-84
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• 2008

This paper describes the application of bioluminescence stimulating agents on a genetically engineered microorganism, Pseudomonas putida mt-2 KG1206, to monitor toluene analogs using in groundwater samples from petroleum hydrocarbon contaminated sites. The maximum bioluminescent response with pure chemicals followed in the order: m-methyl benzyl alchohol > m-toluate > toluene > m-xylene > benzoate > p-xylene > o-xylene. Generally, the bioluminescence production of strain mixed with groundwater samples was dependent on the contaminated total inducer concentrations. However, few samples showed opposite results, where these phenomena may be caused by the complexicity of environmental samples. Two chemicals, SL(sodium lactate) and KNO$_3$, were tested to determine a better bioluminescence stimulant. Both chemicals stimulate the bioluminescence activity of strain KG1206, however, a slightly high bioluminescence was observed with nitrogen chemical. This selected stimulant was then tested on samples collected from contaminated groundwater samples. The bioluminescence activity of all samples mixed with the strain was stimulated with KNO$_3$ amendment. This suggests that the low bioluminescence activity exhibited by the environmental groundwater samples can be stimulated by amending the culture with a proper agent, such as nitrogen compound. These findings would be useful, especially, when strain was used to monitor the groundwater samples contaminated with low inducer contaminants. Overall, the results of this study found the ability of bioluminescence producing bacteria to biosensor a specific group of environmental contaminants, and suggest the potential for more efficient preliminary application of this engineered strain in a field-ready bioassay.

• Clean Technology
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• v.25 no.3
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• pp.238-244
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• 2019

In this study, the ignition characteristics of petroleum-based aviation fuel (Jet A-1), bio aviation fuel (Bio-6308), and blended aviation fuel (50:50, v:v) were analyzed in accordance with change of temperature and pressure. The ignition delay time of each aviation fuel was measured by combustion research unit (CRU) and the compositions of the fuels were analyzed by GC/MS and GC/FID for qualitative and quantitative results. From the results, it was confirmed that the ignition delay times of all aviation fuels were shortened with increasing temperature and pressure. In particular, the effect of temperature was larger than the effect of pressure. Also, the ignition delay time of Jet A-1 was the longest at all measurement conditions, and it was judged that this result is because of the structurally stable characteristics of the benzyl radical generated during the oxidation reaction of the aromatic compound (about 22.48%) in Jet A-1. Also, it was confirmed that Jet A-1 had no section where the degree of shortening of ignition delay time was decreased by increasing temperature, which was because the benzyl radical inhibits the response that can affect the negative temperature coefficient (NTC). The ignition characteristics of blended aviation fuel (50:50, v:v) showed a similar tendency to those of Jet A-1, rather than to those of Bio-6308, so that the blended aviation fuel (50:50, v:v) can be applied to the existing system without any change.

• Clean Technology
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• v.26 no.3
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• pp.204-210
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• 2020

In this study, the ignition characteristics of bio jet fuel (Bio-7629, Bio-5172) produced by F-T process and petroleum-based jet fuel (Jet A-1) were compared and analyzed. The ignition delay time of each fuel was measured by means of a combustion research unit (CRU) and the results were explained through an analysis of the properties and composition of the fuel. The ignition delay time of Bio-5172 was the shortest while that of Jet A-1 was the longest because Jet A-1 had the highest surface tension and Bio-5172 had the lowest viscosity in terms of fuel properties that could affect the physical ignition delay time. As a result of the analysis of the constituents' type and ratio, 22.8% aromatic compounds in Jet A-1 could generate benzyl radical, which had low reactivity during the oxidation reaction, affecting the increase of ignition delay time. Both Bio-7629 and Bio-5172 were composed of paraffin only, with the ratio of n-/iso- being 0.06 and 0.80, respectively. The lower the degree of branching is in paraffin, the faster the isomerization of peroxy radical is produced during oxidation, which could determine the propagation rate of the ignition. Therefore, Bio-5172, composed of more n-paraffin, possesses shorter ignition delay time compared with Bio-7629.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.77-87
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• 2001

Composting is a cost-effective and environmentally-sound technology to treat soils contaminated with hazardous organic pollutants. Pollutants to be treated are as follows: explosives, phenolic compounds, PAHs, petroleum hydrocarbons, pesticides, and etc. Composting systems are windrow, static pile, and in-vessel. Design and operational parameters of composting are aeration modes, temperature, moisture content, nutrient supplement, amendment added, and etc. Appropriate oxygen concentration of composting for contaminated soils are 5~15%, while some compounds are degraded well at the low $O_2$ concentration of 2~5%. The most diverse microorganisms live in the temperature of $25{\sim}40^{\circ}$. 50~90% of the soil field capacity is the moisture content not to make a problem in composting. Assuming a bacterial chemical equation is $C_{60}H_{87}O_{23}N_{12}P$, theoretical C : N : P from bacterial chemical portion is approximately 20 : 5 : 1. It should be noted that the ratio does not apply to the total organic carbon measured in a waste because not all carbon metabolized by bacteria is synthesized to new cellular material. Initial C/N ratio of 25~40 is optimum. It is more economical to recycle soils or composts than to add commercial microbes.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.122-128
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• 1988

Several major polyacetylene compounds were isolated from the petroleum-ether fraction of fresh Korean ginseng roots through solvent fractionation. partition and silica gel column chromatography. Further separation of acetylenic compounds was accomplished by bonded normal phase HPLC utilizing a moderately nonpolar microparticulate column. The preparative separation for the various spectral measurements was carried out by low pressure preparative liquid chromatography. The chemical structure of these polyacetylenes separated was determined by UV. IR/FTIR. $^{1}H$ NMR. mass spectral and elemental analysis. These are identified to be heptadeca-1-en-4.6-diyn-3.9.l0.-triol [1] heptadeca-1.9-dien-4.6-diyn-3-ol. heptadeca-1.8-dien-4.6-diyn-3.10-diol and the 4th was denatured polyacetylene. heptadeca-1.4-dien-6.8-diyn-3.10-diol. Two different p-substituted benzoates of panaxynol were synthesized for the determination of exciton chirality. The circular dichroism spectra in the UV region show that panaxynol p-bromobenzoate and p-dimethyl-aminobenzoate constitute negative exciton chirality [2]. Isolated major polyacetylene compounds were irradiated in aerated solution with 300 nm UV light to obtain the oxidized product at the allylic alcohol center to corresponding carbonyl compounds such as heptadeca-1-en-4.6-diyn-9.10-diol-3-one and heptadeca-1.9-dien-4.6-diyn-3-one. These photooxidation compounds have en-on-diyne chromophore and undergo nucleophilic addition reaction with methanol to yield ${\beta}-methoxy$ carbonyl compounds such as heptadeca-9-en-4.6-diyn-1-methoxy-3-one and heptadeca-4.6-diyn-1-methoxy-9.10-diol-3-one.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.441-451
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• 2013

Samples for estimating concentrations of polycyclic aromatic hydrocargons(PAHs), total petroleum hydrocarbons(TPHs), and benzene-toluene-ethylbenzene-xylene(BTEX) were collected at the tidal flat sediments of 8 coastal sites in Incheon, at seventy-two sampling stations for the surface sediment and twenty-four stations for the sediment core, twice in the spring and fall in 2011. This study was performed to evaluate the distributions of seasonal and spatial concentrations of PAHs, TPHs, and BTEX in the tidal flat sediments. The source origin of PAHs were carried out. The total average concentration of PAHs in the tidal flat sediment was $95.62{\mu}g/kg$. The characteristic of PAHs concentration distributions was observed that the average concentration in the autumn was lower than that in the spring, and higher concentration in the sediment core than the surface sediment, and greater vertical concentration at the top rather than the bottom in the sediment core. The total average concentration of TPHs at all sampling sites was in the value of 46 mg/kg. The characteristic of the TPHs concentration distribution was observed that the average concentration in the fall was much higher than that in the spring, and higher concentration in the surface sediment than the sediment core. The possible source of PAHs inputs were mainly derived from both pyrogenic and petrogenic origin at the surface sediment at Janghwari site and the sediment cores of both Sorae and Okyeon sites, while the rest sites of study areas originated with pyrogenic combustion.

• Applied Chemistry for Engineering
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• v.19 no.6
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• pp.617-623
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• 2008

GTL (gas-to-liquid) fuel produced by the Fischer-Tropsch reaction of carbon monoxide (CO) and hydrogen ($H_2$) is expected to be one of the environmental friendly biomass based alternatives and blended to petrodiesel. In this study, the characteristic of the fuel was analyzed by its concentration differences after blending petrodiesel in domestic market with different amounts of GTL fuel which produced from Shell. Gas chromatography shows that GTL fuel consists of longer paraffin chain than common diesel. GTL fuel showed a high flash point, distillation, kinematic viscosity, and derived cetane number. In addition, GTL fuel showed lower lubricity due to low sulfur content.