• Title/Summary/Keyword: malodor

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Changes in the gas chromatographic sensitivity with its analytical setting: Comparison of TDU and loop-injection system for the analysis of sulfur compounds (GC 분석 시스템의 설정과 그에 따른 감도의 차이: 열탈착 방식 대비 루프주입방식에 의한 황성분의 분석)

  • Kim, Ki-Hyun;Choi, Y.J.;Kim, S.C.
    • Analytical Science and Technology
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    • v.18 no.1
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    • pp.66-73
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    • 2005
  • In this study, we investigated the gas chromatography (GC) and pulsed flame photometric detection (PFPD) system for the analysis of four major reduced S compounds including hydrogen sulfide ($H_2S$); methyl mercaptan ($CH_3SH$); dimethyl sulfide (DMS); and dimethyl disulfide (DMDS) contained in environmental samples. To analyze these compounds in high concentration range (above ppb level), we developed a high mode analytical setting with the loop-injection system. By contrast, we also established a low mode setting for the analysis of low concentration samples (ppt-level samples from ambient air) by the combination with thermal desorption unit (TDU). Comparative analysis of both settings revealed that relative detection properties of four S compounds are systematic enough. The results of high mode analysis indicated that the patterns were systematic among S compounds: $H_2S$ exhibited the lowest sensitivity, while DMDS showed the strongest one. The results were also compared in terms of sensitivity reductions for all compounds by dividing slope ratios between low and high mode system. Although low mode system exhibited significant reductions on the order of a few tens times, their detection characteristics were highly consistent as it was shown in the high mode setting. To learn more about absolute and relative relations between two different modes of S analysis, future studies may have to be directed to cover more complicated nature of GC/PFPD performance.

Effect of aeration on the physicochemical characteristics of livestock feces compost during composting period (퇴비화과정 중 공기공급 여부가 가축분뇨 퇴비의 물리화학적 특성에 미치는 영향)

  • Jeong, Kwang-Hwa;Kang, Ho;Kim, Tai-ll;Park, Chi-Ho;Yang, Chang-Buem
    • Journal of the Korea Organic Resources Recycling Association
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    • v.11 no.4
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    • pp.57-65
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    • 2003
  • Livestock farming is one of several industries that have faced criticism because of its impact on the water quality, soil contamination and air pollution. The livestock feces can cause some environmental problems. The best way to treat the feces is to recycle the manure as an organic fertilizer after fermentation or composting. This study was carried out to investigate the characteristics of composting of manure in several composting conditions. The variations of physicochemical characteristics of each compost piles containing different level of air volume were analyzed throughout the composting period. In this study, pigs manure compost piles mixed with saw dust were composted in 110L of laboratory scale plastic vessels and $1.5m^3$ of small cubic wooden composting vessels for 60days. The compost piles were ventilated continuously with air pump throughout the composting duration. The air volume ventilated into the piles was regulated by chock valve attached to the inlet pipe. The ventilation level was adjusted by 20, 50, 100, 150 and $200L/m^3/mim$, respectively. The highest temperature of the compost increased to $72^{\circ}C$ during composting period. After 20days from beginning of fermentation, concentrations of $H_2S$, $CH_3SH$, DMS and DMDS generated from compost piles were 29, 16, 6 and 5ppb in blow in state compost pile, conversely, in blow out state compost pile, the parameters were 32, 24, 15 and 14ppb, respectively.

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Recycling Technologies of Waste Lubricating Oils and Their Promotion Policies in Korea and Foreign Countries (국내외 폐윤활유의 재활용기술 현황 및 재활용 촉진대책 조사분석)

  • Bae, Jae-Heum;Kwon, Sun-Dae
    • Clean Technology
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    • v.12 no.3
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    • pp.113-127
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    • 2006
  • Waste lubricating oil(WLO)s have been recycled as energy source through direct fuel in cement kilns and fossil power plants, or as fuel oils, or re-refined lubricating base oils. In our country, they have been recycled as low grade fuel oil through chemical treatment process. In 2003, extended producer responsibility (EPR) system was adopted from deposit system on sale of lubricating oils in order to promote their recycleing rate. However, our recycling rate of WLOs have been stagnant(below 70%) for last 5 years. And there has been no research work on recycling of WLOs as re-refined base oil until now in this country. Stabilization technology of thermally cracked oils to reduce tar and malodor and to improve their color for production of high grade fuel oil, and a novel process production of high grade re-refined lubricating base oil from WLOs have been developed and commercialized recently in Canada and U.S.A., respectively. Several countries like Australia, Italy, Germany and U.S.A., etc. are encouraging recycling companies to recycle WLOs as re-refined lubricating oil by giving greater subsidies or benefits compared to other recycling methods. They also adopt a policy to purchase re-refined lubricating oil preferentially in the federal or local governments and to recommend consumers to purchase it willingly. Based on the facts that several advanced countries have adopted a policy to recycle WLOs as re-refined base oil for saving of petroleum resource and reduction of environmental pollution, it is right time to be considered that our present policy for recycling of WLOs should be reevaluated and the new policy of their environmental-friendly and sustainable recycling should be established.

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Conducted to Verify the Effect of Chlorine Dioxide (ClO2) on Odor Reduction at a Commercial Swine Facility (이산화염소 가스분무에 의한 양돈장 악취저감 효과)

  • Song, J.I.;Jeon, J.H.;Park, K.H.;Yoo, Y.H.;Kim, D.H.
    • Journal of Animal Environmental Science
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    • v.17 no.sup
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    • pp.43-50
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    • 2011
  • This study was conducted to verify the effect of chlorine dioxide ($ClO_2$) on odor reduction at a commercial swine facility consisting of a windowless piglet barn and a grower/fattening barn. The windowless piglet barn used a duct ventilation system. Air velocity at very below the upper duct was 4.53 m/s. Air velocity at the lower space around the living space of pigs in the grower/fattening barn was 0.26 m/s. $NH_3$ concentration was around 9ppm and less than 3 ppm before and after the $ClO_2$ spraying, respectively, which was over 70% reduction. There was no $H_2S$ detection. $NH_3$ concentrations measured in the windowless grower/fattening barn and at the exhausted air were 26 ppm and 11ppm, respectively. $NH_3$ concentration at a biocurtain outside was less than 1 ppm. Hence, $ClO_2$ spraying at windowless barns was effectively decreased malodor such as $NH_3$.

Evaluation of Tongue Coating by Digital Tongue Diagnosis System between Halitosis and Non-Halitosis Patients. (디지털 설진기를 이용한 구취군과 비구취군 간의 설태 평가)

  • Jung, Yong-Jae;Kim, Jin-Sung;Oh, Sung-Hwan;Han, Ga-Jin;Kim, Yoo-Seung;Hong, In-A;Park, Young-Sun;Park, Jae-Woo;Park, Kyung-Mo;Ryu, Bong-Ha
    • The Journal of Korean Medicine
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    • v.31 no.1
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    • pp.23-29
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    • 2010
  • Objective: The aim of this prospective, case-controlled study was to assess the difference of the amount of tongue coating between halitosis and non-halitosis patients using a digital tongue diagnosis system (DTDS). Methods: Sixty-five patients complaining of oral malodor were recruited for the study. The level of volatile sulfur compounds (VSC) in the oral cavity of the patients was measured by a portable gas chromatography. All patients were then divided into two groups, the halitosis group ($H_2S{\geq}1.5ng$/10ml, or $CH_3SH{\geq}0.5ng$/10ml) and the non-halitosis group ($H_2S$<1.5ng/10ml and $CH_3SH$<0.5ng/10ml), according to the VSC level criteria published by Tonzetich. Tongue images of the two groups were acquired and analyzed by DTDS, followed by the analysis of the tongue coating scores. Results: The tongue coating scores of the halitosis group were significantly higher than of the non-halitosis group (P=0.033). Furthermore, the difference of the posterior tongue coating between the two groups was more significant (P=0.000). Conclusions: Halitosis patients were shown to have a thicker tongue coating than those in the non-halitosis group. Moreover, the posterior dorsum of the tongue should be observed more cautiously when dealing with halitosis patients. Also, the progress and state of the patient's symptom of halitosis as diagnosed objectively by the portable gas chromatography could also possibly be analyzed instead by the DTDS tongue coating score.

Analysis of Changing Pattern of Noxious Gas Levels with Malodorous Substance Concentrations in Individual Stage of Pig Pens for 24 hrs to Improve Piggery Environment (돈사환경 개선을 위한 생육단계별 돈사내 악취물질 농도 및 유해가스의 1일 변화추세 분석)

  • You, Won-Gyun;Kim, Cho-Long;Lee, Myung-Gyu;Kim, Dong-Kyun
    • Journal of Animal Environmental Science
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    • v.18 no.1
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    • pp.25-34
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    • 2012
  • Noxious gases with malodorous substance concentrations in each stages of pig buildings were determined at a typical 400sow-scale farm to improve piggery environment. Using IAQ-300 and pDR-1000AN, continuous records for the concentration of $NH_3$, CO, $CO_2$, $NO_2$, $SO_2$, $H_2S$, $O_2$, and along with temperature, humidity, dust concentrates from individual pig pens were collected to analyze every 6 hours' condition of indoor environment for 24 hours' period. In most pig houses, the air quality at noon was good, while at night (00:00~06:00), air composition became noxious in all buildings. The order of buildings' air quality for 24 hrs was pregnant > farrowing > nursery > growing > finishing. The cause of air quality differences was presumed to be the differences of stocking density, defecating amount and the length of exposure time of slurry in indoors. In conclusion, well-designed building structure, proper control of stocking density, quick removal of excreta from pig pens and continuous ventilation are prerequisites to improve pig housing environment.

Factors Related to Patients' Satisfaction Level of Treatment Outcome of Oral Malodor (구취치료 후 만족도에 영향을 미치는 예견인자)

  • Lee, Jeong-Yun;Kho, Hong-Seop;Kim, Young-Ku;Chung, Sung-Chang;Lee, Sung-Woo
    • Journal of Oral Medicine and Pain
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    • v.26 no.1
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    • pp.27-38
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    • 2001
  • 본 연구에서는 환자들에 의해 구취와 관련이 있다고 일반적으로 믿어지고 있는 여러 요인들이 치료 후의 환자의 만족도에 미치는 영향에 대해 알아봄으로써 환자의 만족도의 예후를 판단할 수 있는 자료를 마련하고자 하였다. 서울대학교 치과병원 구강진단과에 구취를 주소로 내원한 환자 194명을 대상으로 설문지를 이용하여 구취와 관련성이 있는 것으로 알려져 있는 항목들을 조사하였다. 조사 항목으로는 1) 본인확인가능여부, 2) 타인확인가능 여부, 3) 구취의 기간, 4) 구취의 빈도, 5) 축농증, 6) 비염, 7) 코수술 병력, 8) 콧물이 목뒤로 넘어감, 9) 코막힘, 10) 비호흡 곤란, 11) 구강건조감, 12) 편도선부종, 13) 가래, 14) 신물의 역류, 15) 소화불량, 16) 흡연여부가 포함되었다. 구취의 평가는 portable sulfide monitor인 $Halimeter^{(R)}$(Interscan Co., Chatsworth, CA, USA)를 이용하여 치료 전, 후에 각각 측정하였고, 혀배면의 세정, 치면 세균막 조절, 0.25% $ZnCl_2$ 양치액의 사용을 내용으로 하는 구취의 치료를 시행한 뒤 자신의 구취개선정도에 대해 %로 질문하여 치료 후 만족도를 조사하였다. 각 조사 항목과 치료 후 만족도 사이의 상관관계 및 실제 $Halimeter^{(R)}$ 수치의 개선정도와 만족도 사이의 상관관계를 분석하였으며, Symptom Checklist - 90 Revised(SCL-90R)의 분석결과에 따라 환자를 두 그룹으로 분류하고 두 그룹 사이의 치료 후 만족도의 차이를 조사한 결과 다음과 같은 결론을 얻었다. 1. 본인 및 타인 확인가능여부, 구취가 항상 나는지 여부, 구취의 기간, 축농증, 비염, 코수술 병력, 코막힘, 비호흡 곤란, 콧물이 목뒤로 넘어감, 흡연여부에 따른 치료 후 만족도의 유의한 차이는 없었다. 2. 신물의 역류(p=0.003), 소화불량(p=0.007), 구강건조감(p=0.016), 편도선 부종(p=0.018), 가래(p=0.033)에 따른 치료 후 만족도는 통계적으로 유의한 수준의 차이를 보였다. 3. $Halimeter^{(R)}$ 수치의 개선정도와 만족도 사이의 유의한 상관관계는 관찰되지 않았다(r=0.092, p=0.201).

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Development of Aqueous/Semi-Aqueous Cleaning Agent and its Field Application to Cleaning Process of Electronic Parts (수계/준수계 세정제의 개발 및 전자부품 세정공정 현장적용 연구)

  • Kim, Han-Seong;Cha, An-Jeong;Bae, Jae-Heum;Lee, Ha-Yeoul;Lee, Myung-Jin;Park, Byeong-Deog
    • Clean Technology
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    • v.10 no.2
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    • pp.61-72
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    • 2004
  • In this study, aqueous/semi-aqueous cleaning agents which consist of organic solvent, surfactant, cosurfactant, and water were developed by changing formulation parameters such as organic solvent type and contents, surfactant type and contents, and cosurfactant/surfactant(A/S) ratio, etc.. And physical properties and flux removal of the formulated cleaning agents have been evaluated. Also, the performance of oil-water separation from the rinse water contaminated during the cleaning process was evaluated for its recycling. The formulated cleaning agents in this work expected to have good penetration because of their low viscosity and low surface tension values of 30.2~32.5 dyne/cm. The flux removal with the terpene type cleaning agent was higher than that with hydrocarbon type cleaning agent and two commercial products (CPA(commercial product A), CPB(commercial product B)). And the performance of oil-water separation by gravity settling from the rinse water contaminated with formulated cleaning agent and soils was shown to be very good. The cleaning agents developed in this work were applied to surface mounting technology(SMT) cleaning process for manufacturing electronic parts at L electronic company. As a result, the newly developed cleaning agents showed two times better cleaning speed for removal of solder cream than the conventional ond containing ethanol and IPA(isopropyl alcohol). In addition, malodor and VOC problems generated by the previous organic cleaning agents have been solved in the manufacturing field through introduction of the non-volatile and environmental-friendly cleaning agents to the field.

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Studies of gas chromatographic analysis of malodorous S compounds in air (대기 중 악취황 성분들에 대한 GC 분석의 특성)

  • Kim, Ki-Hyun;Oh, Sang In;Choi, Y.J.
    • Analytical Science and Technology
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    • v.17 no.2
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    • pp.145-152
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    • 2004
  • In this study, analytical characteristics of S gas detection technique were investigated against four major reduced S compounds (including hydrogen sulfide; methyl mercaptan; dimethyl sulfide (DMS); and dimethyl disulfide (DMDS)). To analyze such properties, an analytical system was constructed by combining the GC/PFPD system with the loop injection method. The results of our analysis indicated that response behavior of S gases differs greatly between compounds; H2S exhibited the weakest sensitivity of all compounds, while DMDS with two S-atom compounds the strongest sensitivity. To learn more about their response behavior on GC/PFPD method, their calibration patterns were compared using the three arbitrarily set concentration ranges of low, intermediate, and high. The results showed that calibration patterns of each compound are distinguished because of different factors. There was a line of evidence that calibration of $H_2S$ was affected noticeably by adsorptive loss within the system, whereas those of DMS and DMDS were influenced most sensitively by such factor as the linearity response at a given PMT voltage setting. The overall results of our study suggest that quantification of malordorous S compounds require a better knowledge of compound-specific response behavior against GC detection.

Pulling Force and Manure Spreading Characteristic of Tractor-drawn Animal Slurry Manure Sub-soil Injector (가축분뇨액비 지중살포기의 견인력 및 살포 특성)

  • Choe K. J;Lee S. H.;Ryu B. K.;Oh K. Y.;Park H. J.;Lee S. T.
    • Journal of Animal Environmental Science
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    • v.11 no.1
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    • pp.25-34
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    • 2005
  • The study aimed to develop a tractor drawn animal slurry manure sub-soil injector for arable land and thus, can reduce the waste management cost through effective treatment and utilization of animal slurry manure. The application of animal slurry manure to agricultural land will probably be one of the most effective ways to enrich the soil with vital nutrients. However, some existing slurry manure spenders are not suitable in the field because of their adverse effects to the environment. Based on this premise, a prototype was designed and assembled using 5 sub-soiling standards attached to the sin injector device. The traction force of the Prototype measured in the depth of 10 cm and 15 cm from the ground surface of a paddy field was 1,062 kgf and 1,214 kgf, respectively. A unique feature of the machine was that there was an equal volume of slurry manure flowing from each delivery pipe and regulated by a pressurized container that was likewise synchronized with the speed of the tractor The sub-soiling manure injection system can mitigate or reduce the harmful emission of obnoxious gases and malodor during the injection operation.

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