• International Journal of Automotive Technology
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• 제7권4호
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• pp.501-508
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• 2006

The effect of chemical additives, such as dimethyl ether(DME), ethanol, carbon disulfide on the soot formation were examined numerically. ill this study, the Frenklach soot mechanism was used as a base mechanism to predict the soot formation in the ethane flame. The combination of Westbrook's DME mechanism, Marinov's ethanol mechanism, and chemical kinetic mechanism for hydrogen sulfide and carbon disulfide flames was made with the base mechanism because the DME, ethanol, $CS_2$ additives are added into the ethane fuel. CHEMKIN code was used as a numerical analysis software to simulate the effect of chemical additives on reduction of the polycyclic aromatic hydrocarbons(PAH's) which are soot precursors. From the numerical results it is observed that addition of DME, ethanol and $CS_2$ into ethane fuel can reduce PAH species significantly. That means theses additives can reduce soot formation significantly. Results also strongly suggest suppression of soot formation by these additives to be mainly a chemical effect. Hand OH radicals may be the key species to the reduction of PAH species for additives.

• 농촌의학ㆍ지역보건
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• 제41권2호
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• pp.63-74
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• 2016

Objectives: We surveyed the awareness and current status of using fumigant carbon disulfide for exterminate Curculio sikkimensis among chestnut farmers in Chungnam Province to suggest directions for health education and public relations. Methods: We designed questionnaires to evaluate recognition of fumigant carbon disulfide. We conducted a questionnaire survey to assess recognition and recognition level of fumigant carbon disulfide by the study variables. Results: The recognition status for fumigant carbon disulfide was 74.5%, but the recognition level was low (know well 27.5%). The path of recognition was 45.1% and 15.7% for neighbor and rural technology center, respectively. The recognition status for warning label of fumigant carbon disulfide was 52.9%. Recognition for warning label of fumigant carbon disulfide was tended to increase with high educational attainment, bigger owning land area. Recognition on the content of warning label were 29.4%, 27.5%, 21.6%, and 21.6% for inflammability, toxicity, hazard, and explosiveness, respectively. Using personal protection equipment was tended to increase with the high status of awareness on fumigant carbon disulfide. Conclusions: Health education programs for using fumigant carbon disulfide are needed for chestnut farmers. In addition, publicity information activities about prevention and protection of carbon disulfide poisoning are needed for high risk farmers.

• 한국산업보건학회지
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• 제3권1호
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• pp.22-36
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• 1993

This study was conducted to evaluate the charcoal tube sampling method for carbon disulfide in the air. Breakthrough was investigated according to flow rate, sampling time and air volume. Also the storage stability by storage method and time was investigated. The results are summarized as follows. 1. The samples stored at room temperature($28.2^{\circ}C$), refrigerator($3.8^{\circ}C$) and freezer($-15.6^{\circ}C$) were analyzed every week to five weeks. At one week storage at room temperature, 3.5% of $CS_2$ in the front section of the charcoal tube migrated into the back section and 57.7% at five weeks. The amount of $CS_2$ in the back section of the charcoal increased continuously by storage time. Migration of $CS_2$ was slow at refrigerator, and stopped occur at freezer. Recovery rate $CS_2$ was 52-82% at room temperature and 92-101% at refrigerator, based on the amount at freezer as a reference value. Thus loss was observed at room temperature. 2. When 6-48 L of fresh air were passed through tubes with spiked amounts of 0.379 and 0.759mg sample, the amounts of $CS_2$ in the back section of charcoal were 5.7-132.4 and 0-92% of the amount in the front section, respectively. The total recovery rates of$CS_2$ from 0.379 and 0.759mg spiked sample were 35.7-101.0% and 9l.3-100.1%, respectively. $CS_2$ loss was observed in 0.379mg spiked sample, but not in 0.759mg spiked sample. In the spiked samples, the amount of $CS_2$ in the back section of charcoal was not affected by flow rate when the air volume was controlled. The amount of $CS_2$ in the back section of charcoal increased over sampling time. And the faster the flow rate, the more the migration amount when the sampling time was the same. 3. A known concentration, 10 ppm of $CS_2$, was produced in a 200 L Tedlar bag. When the air volume was 24, 36, 48 L, breakthrough was 5.8, 16.9, 47.4%, respectively. The sampling flow rate of 0.05, 0.1, 0.2 Lpm did not change the breakthrough rate. Breakthrough increased over sampling time. And the faster the flow rate, the more the breakthrough, when the sampling time was the same.

• Journal of Preventive Medicine and Public Health
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• 제26권2호
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• pp.282-292
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• 1993

Neurotoxicity in the workplace may occur with exposure to scores of chemicals. Although large acute outbreaks of the occupational neurological disease are rare, the incidence of occupational neurotoxicity in its subtler aspects is unknown. A working knowledge of both the major occupational neurotoxic solvents and the tools used by cliniical neurologists and neurotoxicologists to evaluate neurotoxicity in working populations is a necessity fur the occupational physician. To investigate the effects of carbon disulfide($CS_2$) on the peripheral nerve system using the nervous conduction study, 105 male workers working in the spinning room of a viscose rayon factory were examined and compared with a sex and age matched, unexposed 105 male controls using t-test analysis. 72.4% of $CS_2$-exposed workers complained of neurological symptoms, and the abnormal cases in nerve conduction study were 48.6%. The abnormal cases of nerve conduction study increased in number according as the age and duration of exposure increased. In this study, asymptomatic workers were confirmed to have subclinical neuropathy by nerve conduction study. Also as there were abnormal cases even in its duration of exposure below 4 years, nerve conduction study turned out to be ways of discovering of early peripheral neuropathy. In nerve conduction study, the amplitude, velocity, F-wave latency and H-reflex of the motor and sensory nerves in both upper and lower extremities were significant different between $CS_2$-exposed workers and the controls. From the pathological viewpoint, both segmental and axonal degenerations were assumed in this study.

• 농촌의학ㆍ지역보건
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• 제15권2호
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• pp.134-140
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• 1990

The causes of occupational hearing loss are physical trauma. ototxic substances and noise. However, only noise induced hearing loss of workers has been reported in Korea as second cause of occupational disease. We report a case of progressive hearing loss in worker exposed to noise. carbon disulfide and hydrogen sulfide for about 13 years. Because of his hearing loss he had to move another position where no noise and no ototoxic substance is. Following audiometry showed that his hearing loss had worsen than before.

• 한국대기환경학회지
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• 제20권1호
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• pp.77-85
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• 2004

In this study, the concentrations of reduced S compounds (including hydrogen sulfide (H$_2$S); methyl mercaptan ($CH_3$SH); dimethyl sulfide (($CH_3$)$_2$S); carbon disulfide (CS$_2$); and dimethyl disulfide (($CH_3$)$_2$S$_2$) were determined from landfill gas (LFG) in three municipal landfill sites in the two cities of Gwang Ju (GJ) and Jeju (JJ), Korea. The S gas concentrations measured in these landfill sites were found to be dominated by H$_2$S with its mean concentration of 850 ppm from 10 LFG samples. Both absolute and relative dominance of H$_2$S was seen to be significant in most LFG samples, except those collected from very old and inactive landfills. Unlike the pattern of H$_2$S, other S gases were typically observed at much reduced concentration levels (a few ppm or less) as follows: DMS (3.5); $CH_3$SH (1.3); CS$_2$(1.2); and DMDS (0.02 ppm). If compared equally in mass concentration unit (mg m$^{-3}$ ), H$_2$S generally explained far above 90% of all S gas masses determined concurrently. Moreover, as its mass concentration commonly exceeds those of the major aromatic VOC components in LFG (like benzene and toluene), it appeared to be one of the most dominant gaseous components emitted as LFG in a quantitative sense.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4047-4051
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• 2012

A new and facile protocol for the synthesis of dithiocarabamate in EtOH/$H_2O$ is described. Reaction of aromatic and aliphatic amines with $CS_2$ and 3,4-dihydro-2H-pyran in the presence of N,N,N',N'-tetrabromobenzene-1,3-disulfonamide [TBBDA] and poly(N-bromo-N-ethylbenzene-1,3-disulfonamide) [PBBS] gives the corresponding dithiocarbamates in good to high yields.

• 한국산업보건학회지
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• 제11권3호
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• pp.206-211
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• 2001

This article describes identification and quantification of benzene in the casting process. Air samples around the casting process were taken by using personal air sampler attached charcoal tube and desorbed by carbon disulfide. The identification and quantitative analysis of benzene have been performed by GC-MS and GC-FID. Calibration range of standard solutions for benzene was prepared in range from 0.1 to 2 times of TLVs concentrations($1.4{\sim}28{\mu}g/1m{\ell}$ CS2) and the limit of detection was $0.11{\pm}0.002{\mu}g/1m{\ell}$ CS2. Benzene detected in airborne was ranged in 4.0ppb~104.7ppb.

• 대한환경공학회지
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• 제28권2호
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• pp.158-164
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• 2006

축산 관리시설로부터 발생하는 악취와 이를 저감하려는 연구들이 국내에서 활발히 진행되고 있다. 축산 관리시설로부터 발생하는 악취를 저감시키기 위해서는 주요 악취 기인 화합물 및 이들의 발생 메커니즘이 규명되어져야 하는데, 이를 위해 정확하고 객관적인 악취 화합물의 분석 기술이 필수적이다. 이에, 본 연구에서는 고상(固想) 미세추출법(SPME; Solid-phase microextraction)을 이용하여 현장에서 대상 화합물을 흡착하고, GC/MSD 혹은 GC/FID를 이용하여 정량 분석하여 화합물의 손실을 최소화 하는 분석 방법을 소개하고자 한다. 본 연구에서의 대상 악취 화합물은 trimethylamine(TMA), carbon disulfide($CS_2$), dimethyl sulfide(DMS), dimethyl disulfide(DMDS), acetic acid(AA), propionic arid(PA) 그리고 n-butyric acid(BA)이다. SPME-GC 검정곡선의 직선성을 나타내는 결과로 TMA의 결정계수($R^2$)는 0.984(0.056-1.437), $CS_2$는 0.996(0.039-0.999), DMS는 0.994(0.029-0.756), DMDS는 0.995(0.024-0.623), AA는 0.992(0.068-1.314), PA는 0.955(0.047-0.940), 그리고 BA는 0.976(0.036-0.712)이었다. 분석 검출한계는 AA, PA, BA, TMA, DMS, $CS_2$, DMDS에 대하여 각각 5.67, 6.39, 5.78, 25.2, 0.098, 0.363, 0.099 ppbv이었다. 본 연구에서 제안한 방법을 이용하여 계사, 돈사 및 우사에서 발생하는 악취화합물을 정량 분석하였다. 계사 내부에서 DMDS를 제외한 모든 화합물이 검출이 되었는데, 문헌에서 보고된 human odor threshold를 초과하였다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.399-405
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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 compounds: H2S exhibited the lowest sensitivity, while DMBS 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. Hydrogen sulfide($H_2S$) was over in summer about low level of olfactory sense 410 ppt, Methyl mercaptan(C$H_3SH$) was over in apring and summer about low level of olfactory sense 70, Dimethyl sulfide(DMS) was not over in four season about low level of olfactory sense 2,200 ppt. Carbon disulfide($CS_2$) was not over in four deason about Tow level of olfactory sense 210,000, Dimethyl disulfide(DMDS) was not over in summer about low level of olfactory sense2,000.