• 환경위생공학
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• 제9권1호
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• pp.29-37
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• 1994

Anaerobic treatment of wastewater of the red- bean processing industry was carried out and discussed an anaerobic sludge bed reactor( ASBR) as a preliminary study to evaluate applicability of given processes. The dimension of reactor were same as 0.09m- ID$\times $1.5m- height. The type of substrate and the hydraulic retention time( HRT) were considered as experimental variables. The synthetic wastewater with glucose in the laboratory, the wastewater from the red bean processing industry mixed with synthetic wastewater with variation of mixing percent were fed as substrate. The hydraulic retention time was changed from one day to five days. The gas production, the methane content in produced gas, efficiencies of COD removal and 55 removal were evaluated as principal characteristics. With synthetic wastewater as a substrate and at a hydraulic retention time of one day, characteristics of ASBR was the gas production(12$\ell$/day ), the methane content of produced gas(60%), the efficiency of COD removal(92%) and 55 removal(30%). With the real wastewater and at a hydraulic retention time of one day, the gas production and the efficiency of COD removal of the ASBR decreased with the proportion of real wastewater. The gas production and the efficiency of COD removal with real wastewater only was decreased to 70% and 87% of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. With real wastewater only as a substrate in the ASBR, the gas production was decreased with an increase of HRT, but the efficiency of COD removal increased with HRTI like the usual trend reported. As a conclusion, the wastewater of the red- bean Processing industry could be treated by anaerobic digestion successfully in the ASBR.Anaerobic treatment of wastewater of the red- bean processing industry was carried out and discussed an anaerobic sludge bed reactor( ASBR) as a preliminary study to evaluate applicability of given processes. The dimension of reactor were same as 0.09m- ID$\times $1.5m- height. The type of substrate and the hydraulic retention time( HRT) were considered as experimental variables. The synthetic wastewater with glucose in the laboratory, the wastewater from the red bean processing industry mixed with synthetic wastewater with variation of mixing percent were fed as substrate. The hydraulic retention time was changed from one day to five days. The gas production, the methane content in produced gas, efficiencies of COD removal and 55 removal were evaluated as principal characteristics. With synthetic wastewater as a substrate and at a hydraulic retention time of one day, characteristics of ASBR was the gas production(12$\ell$/day ), the methane content of produced gas(60%), the efficiency of COD removal(92%) and 55 removal(30%). With the real wastewater and at a hydraulic retention time of one day, the gas production and the efficiency of COD removal of the ASBR decreased with the proportion of real wastewater. The gas production and the efficiency of COD removal with real wastewater only was decreased to 70% and 87% of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. However, the methane content in produced gas and the efficiency of 55 removal with real wastewater only was increased significantly by 1.25 times and two times of those with synthetic wastewater only, respectively. With real wastewater only as a substrate in the ASBR, the gas production was decreased with an increase of HRT, but the efficiency of COD removal increased with HRTI like the usual trend reported. As a conclusion, the wastewater of the red- bean Processing industry could be treated by anaerobic digestion successfully in the ASBR.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1703-1707
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• 2013

A fast and simple sampling and sample preparation device, (NTD) has been developed and applied to sample and analyze volatile components from ground coffee beans. Coffee fragrances and other volatile organic compounds (VOCs) were sampled by the NTD and then analyzed by gas chromatograph-mass spectrometry (GC/MS). Divinylbenzene (DVB) particles (80/100 mesh size) were the sorbent bed of the NTD. More than 150 volatile components were first identified based on the database of the mass library and then finally 30 fragrances including caffeine were further confirmed by comparing experimental retention indices (i.e. Kovat index) with literature retention indices. Total sampling time was 10 minutes and no extra solvent extraction and/or reconstitution step need. Straight n-alkanes (C6-C20) were used as retention index probes for the calculation of experimental retention indices. In addition, this report suggests that an empty needle can be an alternative platform for analyzing polymers by pyrolysis-GC/MS.

• 분석과학
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• 제7권3호
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• pp.329-338
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• 1994

기체 크로마토그래피에 의한 단일 컬럼상에서 천연가스 성분의 용리거동을 알아보았다. 천연가스 성분의 용량인자인 k'값을 결정하기 위하여 불감시간 $t_0$를 동족계열에 의한 외삽법으로 구하였다. 여러 가지 온도에서 $C_1$부터 $C_5$까지 동족계열의 머무름 시간을 탄소수에 대해서 도시하면 어느 한 점에 수렴하게 되는데, 이 점을 $t_0$로 정하였다. n-부탄을 기준으로 온도에 따른 컬럼효율의 변화를 알아본 결과 온도가 증가할수록 컬럼효율은 증가하였으나, 분리시간이 짧은 시료들의 분리도는 감소하였다. 28% DC-200 정지상에서 흡착엔탈피 변화값을 구하였고, 천연가스 성분들의 머무름 메카니즘을 알아보기 위해 log $t_R$, log k' 및 log ${\alpha}$값을 van der Waals 부피(Vw), 분자간 연결지수(X) 및 소수성 계열상수(f)와의 희귀분석을 수행한 결과 log k'과 Vw 및 f가 높은 상관관계를 보여 주었다. 천연가스 성분의 물리적 성질과 물리적 파라미터와의 상관관계를 알아본 결과는 Vw는 분자량과 발열량(${\Delta}H_{comb}$), X는 끓는 점, f는 분자량, 끓는 점 및 발열량과 상관계수가 0.99 이상으로 높은 상관관계를 나타내었다. Vw와 발열량과의 회귀방정식을 이용하여 $C_6$호부터 $C_{10}$까지의 발열량을 예측한 결과 문헌값과 0.2%의 상대오차 범위내에서 일치하였다.

• 상하수도학회지
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• 제25권6호
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• pp.815-824
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• 2011

In this study, a non-thermal plasma system was employed to simultaneously remove odorous compounds and organic sludge. The system consisted of two reactors; the first one was the non-thermal plasma reactor where ozone was produced by the plasma reaction and the ozone oxidized hydrogen sulfide, the model odorous compound, and then the ozone-laden gas stream was introduced to the second reactor where wasted sludge was disintegrated and solubilized by ozone oxidation. In this study, the gas retention time (GRT) and the hydraulic retention time (HRT) were changed in the two-reactor system, and the effects of GRT and HRT on reduction efficiencies of odor and sludge were determined. As the GRT increased, the ozone concentration increased resulting in an increasing efficiency of hydrogen sulfide removal. However, the overall ozone loading rate to the second sludge reactor was the same at any GRT, which resulted in an insignificant change in sludge reduction rate. When HRTs in the sludge reactor were 1, 2, 4 hours, the sludge reduction rates were approximately 30% during the four-hour operation, while the rate increased to 70% at the HRT of 6 hours. Nevertheless, at HRTs greater than 4 hours, the solubilization efficiency was not proportionally increased with increasing specific input energy, indicating that an appropriate sludge retention time needs to be applied to achieve effective solubilization efficiencies at a minimal power consumption for the non-thermal plasma reaction.

• 한국식품영양과학회지
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• 제19권6호
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• pp.555-564
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• 1990

과실쥬스와 같은 자연 생산물의 동결건조에 있어서 가공처리중 휘발성분의 보유력 변화를 알아보기 위하여 headspace gas chromatography 기술의 특징을 이용하여 동결건조 속도, 초기 고형물의 함량 및 압력 등이 어떠한 영향을 미치는가에 대한 실험결과는 다음과 같다. 동결건조 속도가 휘발성분의 보유력에 대한 영향은 현저하였으며, 동결시간이 길수록 뚜렷하였다. 동결 건조 제품에서 휘발성분의 보유력은 동결에 의해 영향을 받았다. 동결건조 조건하에서 가장 많은 휘발성분의 손실은 동결건조 초기단계, 즉 1~2 시간 사이에서 일어났다. 휘발성분의 보유력은 초기 고형물의 함량이 많을수록 높았다. 동결속도가 빠를 때보다는 늦을 때가 휘발성분의 보유력이 높았으며 높은 압력에서보다 낮은 압력에서 높았다.

• 약학회지
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• 제39권3호
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• pp.283-288
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• 1995

Rapid gas chromatographic profiling method was applied to saliva from healthy subjects for the analysis of free organic acids. Saliva samples were first saturated with NaHCO$_{3}$ and extracted with diethyl ether. The aqueous phase was solid-phase extracted using Chromosorb P as the adsorbent and diethyl ether as the eluent after the acidification and NaCl saturation, followed by triethylamine treatment. The resulting tiiethylammonium salts of acids were directly converted into stable tert.-butyl-dimethylsflyl derivatives, with subsequent analysis by dual-capiuary column gas chromatography and gas chromatograpy -mass spectrometry. From the ten saliva samples studied, twenty eight free organic acids including various fatty acids, hydroxy acids, dicarboxylic acids, md aromatic acids were tentatively identified. Among the acids identified , the concentration of lactic acid was highest for five saliva samples while $\alpha$-hydroxyisocaproic acid was most abundant for me sample, and succinic acid and glycolic acid for two samples. respectively. When the GC profiles were simplified to the corresponding acid retention index spectra of bar graphical form, they presented characteristic patterns for each individual.

• 유기물자원화
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• 제8권3호
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• pp.124-130
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• 2000

본 연구는 가솔린 휘발가스를 퇴비 바이오필터로 처리시 공정조절 인자인 체류시간과 충전깊이의 영향을 살펴보고 공정개선방안을 제시하고자 실시하였다. 체류시간을 4, 10, 그리고 20분으로 변화하여 실시한 결과 TPH의 효율적 제거를 위해서는 10분이상의 EBRT가 요구되었으며 $40g/m^3$(충전물질)/hr 미만의 부하로 운전하는 것이 효과적이었다. BTEX는 체류시간 4분에서는 부하량이 약 $1.5g/m^3$(충전물질)/hr 이상으로 증가하자 더 이상 제거 능력이 증가하지 않았으며, 체류시간 10분에서는 약 $5.3g/m^3$(충전물질)/hr의 부하량에서 $4.5g/m^3$(충전물질)/hr 이상이 제거되었다. 이로써 안정적인 제거를 위해서는 BTEX도 10분 이상의 체류시간이 필요하였다. 충전깊이는 25, 50, 75, 그리고 100cm로 하였다. TPH 제거량을 증가시키기 위해서는 단순히 충전깊이를 증가시키는 것보다 가스체류시간 및 유입부하량 등 다른 공정인자들을 제어하는 것이 더욱 효과적이었다. BTEX의 경우에는 다른 공정인자의 조절도 중요하지만 충전깊이를 1m 정도로 하면 다른 공정인자의 조절에 큰 어려움 없이도 제거효율을 향상시킬 수 있을 것이다.

• 대한화학회지
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• 제35권6호
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• pp.659-666
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• 1991

질소를 함유한 흥분제와 마약성 진통제 18종류의 약물들을 gas chromatography-nitrogen phosphorus detector(GC-NPD)를 사용하여 human urine으로부터 동시에 신속하게 분석할 수 있는 최적조건을 찾기 위하여 pH 변화와 추출용매 변화에 따른 회수율을 조사하였다. pH 8.5에서 에테르를 추출용매로 사용하였을 때 가장 적은 방해영향과 가장 좋은 회수율을 나타냈다. NPD에 대한 각 약물들의 상대 감응인자를 구하였고, 이 상대감응인자는 약물이 가지고 있는 질소원자의 갯수가 증가할수록 작은 값을 나타냈다. 생체시료 중의 약물들을 신속하게 검정하기 위하여 내부표준물질인 diphenylamine에 대한 relative retention time(RRT)을 작성하였다. 상대머무름 시간은 0.1% 이하의 정밀도를 나타냈다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.58-59
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• 2018

In this study, firing experiments were carried out to confirm the foamability of the expansive shale collected from the local area. When expansive shales are subjected to high temperature heat, gas is generated inside and voids are formed. Due to this phenomenon, shale is used as a raw material for lightweight aggregate. Experiments were carried out with different plastic temperature and residence time to find the appropriate plastic temperature for this expansive shale. As a result, the higher the plastic temperature, the more the surface viscosity increased and the gas generated inside were retained. Resulting in a number of internal voids. However, even if the plastic temperature or the medium temperature is high, it is confirmed that sufficient gas is not generated when the residence time is shortened.

• 한국식품과학회지
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• 제21권6호
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• pp.749-754
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• 1989

탱자(Poncirus trifoliata)의 향기성분을 분석하기 위해 gas co-distillation 방법으로 정유를 추출한 후 GC/retention index(RI)와 GC/MS를 이용해 multi-dimensional analysis를 행하였다. Gas co-distillation 방법으로 탱자의 향도 그대로 지니며 기기분석에 적합한 정유를 얻을 수 있었다. 향기성분의 확인작업에는 GC/RI와 GC/MS를 상보적으로 사용한 multi-dimensional analysis가 효과적이었으며 GC/RI로만 확인할 경우 극성이 다른 두 가지 column을 사용해서 신뢰도를 높일 수 있었다. 탱자에 다량 함유되어 있는 향기성분들은 limonene, myrcene, ${\beta}-caryophllene,\;trans-{\beta}-ocimene,\;{\beta}-pinene$, 3-thujene, 7-geranyloxycoumarin 등으로 밝혀졌으며 확인된 30개의 성분 중 cis-3-hexenyl acetate, n-hexyl acetate, 2-methyl acetophenone, elixene 그리고 elemicine 등은 이제까지 감귤류에서는 발견되지 않았던 새로운 성분들이다.