• 산업식품공학
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• 제13권3호
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• pp.190-194
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• 2009

본 연구는 김치건조분말을 제조하는 과정에서 김치의 발효과정과 건조 전후에서 나타나는 향기성분의 변화를 조사하고, $\beta$-cyclodextrin의 첨가로 인한 향기성분 포집효과를 검증하고자 GC-MS를 이용하여 분석실험을 실시하였다. 김치를 제조하여 $20^{\circ}C$에서 발효시켰을 때, 초기 2일째는 dimethyl sulfide와 carbon disulfide가 생성되었고, 7일이 경과하였을 때, dimethyl disulfide, methyl 2-propenyl disulfide, allyl methyl sulfide, and di-2-propenyl disulfide의 황화합물이 주된 향기성분으로 검출되었다. 본 김치시료를 감압건조 하였을 때, 11개 화합물이 검출되지 않았고 dimethyl sulfide, acetaldehyde and methanethiol를 주로 포함하는 13개 화합물이 잔류하였다. 건조공정 중에서 김치향기성분의 손실을 최소화하고자 0.25-1.0% 농도의 $\beta$-cyclodextrin을 건조보조제로 첨가하였을 때, 향기성분의 포집효과에 의해 건조 김치분말에 잔류하는 향기성분의 함량이 평균 3% 증가하였다. 본 연구결과로 볼 때 cyclodextrin은 건조 김치분말 제조공정뿐만 아니라 건조식품제조에서 건조보조제로 효과적으로 사용할 수 있을 것으로 보인다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.145-146
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• 2002

Tribological properties of co-sputtered Molybdenum disulfide $(MoS_2)/Carbon\;(C)$ films were studied and compared with those of sputtered $MoS_2$ films. Friction tests were carried out using pin-on-disk friction testers to evluated their friction and wear behaviors in a vacuum ($10^{-5}Pa$), air and humid air of 30, 50, 80% RH. $MoS_2/C$ (14%) composite films exhibited about 9 times longer wear life in a vacuum and about 6 times longer wear life in dry air than $MoS_2$ films did. They also showed stable low friction coefficient of about 0.02 in a vacuum. In humid air, however, $MoS_2/C$ composite films hardly showed good tribological properties.

• 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.

• 대한화학회지
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• 제55권6호
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• pp.988-993
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• 2011

Cyclodehydration of 6-amino-5-cyano pyrimidine derivative (2) afforded pyrimidoisoindole derivatives (3). Compound (3) reacted with carbethoxymethylene derivative to give pyridopyrimidine derivatives (5a,b). Compound (3) was also reacted with formamide to give the corresponding pyrimidopyrimdine derivatives (6) that condensed with benzaldehyde to give Schiff's base (7). Refluxing of compound (3) with triethyl orthoformate afforded compound (8) that cyclized with ammonium hydroxide giving the same compound (6). Compound (8) cyclized with hydrazine hydrate giving compound (9) which also cyclized with triethyl orthoformate affording compound (10). Diazotization of compound (3) led to the formation of triazinopyrimidine derivative (11). Cyclization of compound (11) upon treatment with hydrazine hydrate afforded compound (12). Compound (15) was prepared from reaction of compound (3) and ethylenediamine in presence of carbon disulfide. The behaviour of compound (15) toward benzoyl chloride, triethyl orthoformate, nitrous acid and/or carbon disulfide was also described. All proposed structures were supported by elemental analyses, spectroscopic data and some of the new products showed antimicrobial activity.

• 월간산업보건
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• 제7호통권243호
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• pp.62-67
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• 2008

• 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.

• 한국식품과학회지
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• 제20권4호
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• pp.606-612
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• 1988

신선한 표고버섯(Lentinus edodes) 및 건조 표고버섯의 휘발성 향기성분을 수증기-추출장치를 이용하여 추출한 후 GC및 GC-MS에 의해서 비교 분석하였고 신선한 표고버섯의 휘발성 향기성분 생성에 미치는 pH의 영향을 조사하였다. 확인된 29개의 휘발성 향기성분 중 신선한 표고버섯에서는 1-octen-3-ol이 전체 향기성분의 약 74.7%, 건조표고버섯 에서는 1,2,4-trithiolane이 약 66.3%를 차지하였다. 그외에도 $C_8$ 화합물로서는 3-octanone 1-octen-3-one, 3-octanol, cis-2-octenal, 3-octanol, 및 cis-2-octenol, 함황화합물소는 carbon disulfide, dimethyl disulfide dimethyl trisulfida, 1-(methyl thio)-dimethyl disulfide 1,2,4,5-tetra-thiane이 확인되었다. 신선한 표고버섯을 침지하였을 때 $C_8$화합물은 pH $6.0{\sim}7.0$, 함황화합물은 pH $8.0{\sim}9.0$에서 많이 생성되었다.

• 대한화학회지
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• 제54권4호
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• pp.414-418
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• 2010

Ethyl 1-aminotetrazole-5-carboxylate (1)를 hydrazine hydrate와 반응시켜서 대응하는aminohydrazide 2를 합성한 후에, 화합물 2를carbon disulfide와 반응시켜서 1,3,4-oxadiazole-5-thiol structure 3을 합성하였다. 얻어진 화합물 3을 either chloroacetone 또는 ethyl chloroacetate와 반응시켜서S-acyl 1,3,4-oxadiazole 유도체인 4 와 5를 합성하였으며, 또한 hydrazine hydrate와 반응시켜서 4-amino-1,2,4-triazole-5-thiol 유도체인 6을 합성하였으며, 화합물 6을 glacial acetic acid와 반응시켜서 6-methyl-1,3,4-triazolo[3,4-b]-1,3,4-thiadiazole (7)을 합성하였다. 한편, 알려진 방법에 따라서, 화합물 1로부터 tetrazolo[5,1-f]-1,2,4-triazine 9을 얻은 다음에, 화합물 9를 carbon disulfide와 반응시켜서 8-thione 유도체인 10을 합성한 후에, 대응하는 화합물 11, 12 및 13을 합성하였다. 얻어진 화합물13을 이용하여1,2,4-triazolo[4,3-d]tetrazolo[5,1-f]-1,2,4-triazines 14와 15를 합성하였다. 새롭게 합성한 화합물들의 화학구조를 확인하였으며, 합성한 화합물들에 대한 항균 활성시험을 수행하였다.

• Elastomers and Composites
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• 제45권1호
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• pp.32-39
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• 2010

본 연구에서는 PTFE 100%, PTFE 90% + 카본블랙 10%, PTFE 85% + 유리섬유 15%, PTFE 80% + 유리섬유 15% + 이황화몰리브덴($MoS_2$) 5%, PTFE 75% + 유리섬유 25%, PTFE 75% + 카본블랙 18% + 흑연 7% 복합물들의 기계적 물성을 연구하고 DSC 및 TGA를 이용하여 복합물의 융해열(${\Delta}H_f$)과 열적 안정성에 관한 실험을 수행하였다. 또한 내구시험법을 이용하여 PTFE 오일씰의 립부 마모형상 및 마모량을 측정하였다. SEM을 이용하여 마모표면을 관찰하였다. PTFE에 유리섬유와 이황화몰리브덴을 첨가하여 실험결과에 따르면, 인장강도 및 신율은 저하되지만 경도, 내마모성 및 내구성 보강의 효과를 얻을 수 있음을 알 수 있었다. PTFE 복합재질 6가지중 PTFE 80% + 유리섬유 15% + 이황화몰리브덴 5%의 복합물이 PTFE 오일씰 제작에 가장 알맞은 재질임을 확인하였다.

• 반도체디스플레이기술학회지
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• 제18권3호
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• pp.52-59
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• 2019

Styrene-butadiene rubber (SBR) composites, incorporated with graphene, molybdenum disulfide and their hybrid in different filling ratio, were fabricated by a two roll-mill. The dispersion states of all the samples' matrix were employed by carbon black dispersion tester. The curing properties of the pre-vulcanized rubber composites were investigated, after molding by heating press machine, the tensile strength, storage modulus, friction coefficient, the swelling property had also been tested according to ASTM. The composite G1M10 (filling with 1 phr graphene and 10 phr molybdenum) showed the best mechanical properties and viscoelastic properties in this research with a better filler dispersion state and more compact matrix structure.