• 전기화학회지
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• 제4권4호
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• pp.160-165
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• 2001

황산원자를 포함하는 mercapto화합물은 도금시 전착속도를 증가시키는 첨가제로 알려져 있는데, 이 중 4가지의 mercapto 화합물을 선정하여 농도를 변화시켜가며 Hull cell test, Haring-Blum cell test, cathodic polarization, EQCM(Electrochemical Quartz Crystal Microbalance)등을 이용하여 도금특성 및 throwing power를 알아보았다. Cathode polarization 및 EQCM을 통한 구리 전착량을 알아본 결과 4가지의 mercapto 화합물 중 3-mercapto-1-propanesulfonic acid가 activator로서 가장 적당하였으며, 그 농도가 20 ppm에서 throwing power를 증가시키고, 농도 및 활성 과전압이 오직 $Cl^-$만 포함되었을 때보다 cathodic scan시 100 mV 만큼 shift되어 증착속도를 증가시킴을 알 수 있었다.

• Journal of Oral Medicine and Pain
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• 제25권1호
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• pp.41-51
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• 2000

This study was performed to investigate the effect of three modalities commonly used for reduction of oral malodor and to review the contributing factors for halitosis. For this study, 45 subjects of good general health in their third decades were selected, and they were divided into three groups by each modality, that is, tongue scraping, $ZnCl_2$ mouth rinse, and periodontal treatment. Subjective sense of halitosis, diets, Oral hygiene index based on tooth brushing and tongue brushing habit, resting salivary flow rate, gingival index, degree of tongue coating were recored in the Halito-Chart designed by the author. Oral malodor converted from volatile sulfur compound was measured by the Halimeter$^{(R)}$(Interscan Co., USA), and the correlation between the oral factors and pre-treatment halimeter score were analysed. Data obtained were analysed by the SPSS windows program and the results of this study were as follows : 1. There were no significant correlation between oral factors such as oral hygiene index, salivary flow rate, gingival index, degree of tongue coating and pre-treatment halimeter score. 2. Difference between pre- and post-treatment halimeter score by the three modalities were significant, but correlation between pre- and post-treatment score within group was most significant in the periodontal treatment group followed by the tongue scraping group and lowest in the $ZnCl_2$ mouth rinse group. 3. Reduction of halimeter score was significant only in subjects with relatively more tongue coating in the tongue scraping group, but in the $ZnCl_2$ mouth rinse group and in the periodontal treatment group, the modality applied to each group had same significant effects without regard to the degree of oral hygiene index or gingival index. 4. Men had more tongue coating than women, and reduction of halimeter score was significant in men, but not in women.

• KSBB Journal
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• 제15권3호
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• pp.254-261
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• 2000

공시균주인 Thiobacillus ferrooxidans(ATCC 19859)와 광양의 폐광산수에서 분리한 Thiobacillus KY를 이용하여 황칠광(pyrite, FeS2)에 대하여 30일간 침출반응하여 반응시간에 따른 황철광의 표변특성 변화를 관찰하였다. Thiobacillus ferrooxidans (ATCC 19859)의 경우 반응시간 20일 경과 후Thiobacillus KY는 반응 시간 10일 후 각각 황철광 표변에 결정구조의 변화가 관찰되었 다. FezS의 결합에서 S-Fe-S의 결합이 끊어점에 기언하는 [311] 평면의 상대적으로 감소와 침출시간 증가에 따른 [111]평면과 [220]의 상대적으로 노출의 증가의 특정을 나타냈다. SEM-EDS 결과 침출시키기 전의 시료는 Fe 36.97%, S 45.71%, Si 16.94% 이며 반응이 진행됨에 따라 황성분의 비율이 증가하였다. 또한 노출된 황칠광 위에 칩착물은 S 59.56%, Fe 38.9%, Si 1.53%의 원지구성비를 가진 물질이었다. 이러한 결과로 부터 침출이 진 행되면서 결정구조의 변화와 황과 철의 침착물에 의하여 황철광 의 표면이 비활성화된다는 결론을 도출할 수 있다.

• 미생물학회지
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• 제40권2호
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• pp.127-132
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• 2004

활성 오니법에 의한 하수처리장 포기조에서 슬러지를 채취하여 황화물계 악취제거 균주인 Thiobacillus속의 선별 배지로 50개 균주를 분리하였다. 분리한 50개 균주의 동정 결과 7개 균주는 Thiobaecillus neapolitanus, 4개 균주는 Thiobacillus tepidarius, 5개 균주는 Thiobacillus denitrificans, 23개 균주는 Thiobacillus versutus, 2개 균주는 Thiobacillus intetmedius, 9개 균주는 Thiobacillus perometabolis로 동정되었다. 분리 동정한 균주들로 고효율 황화물계 악취(황화수소, dimethyl sulfide, methyl disulfide)제거 균주 스크린을 하였다. 그 결과 황화수소, dimethyl sulfide에 대하여 KT5l(Thiobacillus versutus)균주가 각각 l00％, 85％로 가장 높은 제거율을 보였다. Dimethyl disulfide의 경우에는 전체 균주가 다른 악취성분에 비해 제거율이 낮았는데 KT8l균주가 26％로 가장 높은 제거율을 보였다. 스크린 결과 KT5l균주를 선별하였으며, 선별된 KT51균주를 밀폐된 모형 생물학적 처리 반응기에 적용하여 황 화합물의 제거 효율을 비교한 결과, 황화수소의 경우, 100 ppm을 주입 후 균주 적용전의 운전 결과는 30분 이후에 0.02 ppm 미만(99.8％)으로 제거한 반면, 균주 적용 시의 운전 결과는 15분에 황화수소를 0.02 ppm 미만(99.8％)으로 처리하였다.

• Food Science and Biotechnology
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• 제16권5호
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• pp.822-827
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• 2007

The aroma characteristics and antioxidative activity of volatile compounds in heat-treated garlic (Allium sativum L.) were evaluated. The garlic was heated to various temperatures (100, 110, 120, and $130^{\circ}C$) for different lengths of time (1, 2, and 3 hr). The volatile compounds of heated garlic were extracted by simultaneous steam distillation extraction (SDE). Aroma compound profiles were analyzed by gas chromatography/mass spectrometry (GC/MS) and antioxidative activity was measured by 2,2-diphenyl-2-picrylhydrazyl (DPPH) assay and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) cation decolorization assay. The major aroma compounds were sulfur compounds such as dimethyl disulfide, 2-propen-1-ol, methyl-2-propenyl disulfide, dimethyl trisulfide, diallyl disulfide, methyl-2-propenyl trisulfide, and di-2-propenyl trisulfide. DPPH radical scavenging activity (EDA, %) and the ascorbic acid equivalent antioxidant activity (AEAC) of volatile compounds in heated garlic increased significantly with the increase of temperature and time (p<0.001). The EDA (%) and AEAC of raw garlic were 26.8%/10 mg garlic and 39.05 mg ascorbic acid equivalent per g sample. After heat treatment, the highest values were 40.50%/10 mg garlic for EDA (%) and 46.43 mg ascorbic acid equivalent per g sample for ABTS.

• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1243-1249
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• 2011

This study was performed to examine the use of NaOCl as an alternative antimicrobial compound in winemaking because of the potential health problems that may arise as a result of the use of $SO_2$. For this, the blank (non-treated), control ($SO_2$-added), and sample (NaOCl-treated) wines were made, and microbial and chemical changes including sensory characteristics were analyzed during the fermentation periods. Treatment of grapes with NaOCl decreased the initial contaminating microbial population in grape must, resulting in higher growth of yeast and lactic acid bacteria. After 200 days of fermentation, the chemical analysis of sample wine revealed that it had higher ethanol content, redness ($a^*$), and concentrations of fruity ester compounds and lower total acidity than the control. In the sensory analyses, the sample wine obtained a higher overall acceptability score (5.70) than the control (4.26). This result reveals that NaOCl can be used as an alternative to $SO_2$ in winemaking for inhibiting the growth of contaminating microorganisms.

• 대한화학회지
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• 제48권2호
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• pp.156-160
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• 2004

LPG용 고압고무호스의 가소제 추출률에 대하여 연구하였다. 가소제 추출을 위한 침지용 용매는 프로판, n-부탄, n-펜탄, n-헥산, n-헵탄이며, 프로필렌, 1,3-부타디엔, 1-펜텐, 1-헥센, 에탄티올, t-부탄티올, 황화에틸메틸, 황화이메틸으로 조성되어 있다. 다중회귀분석으로 가소제 추출량과 침지용매의 설명인자사이의 상관관계를 다음과 같이 얻을 수 있었다. PE(wt%)=7.5193(${\pm}$0.2466) - 0.585000(${\pm}$0.05437)Carbon${\sharp}$ + 2.3294(${\pm}$0.1967)DB + 2364(${\pm}$896.2)SH (N = 13, F = 24.135, R$^2$ = 0.8894, R$_{adj}^2$ = 0.8526, Variance = 7.588) 증기압이 높고 극성도가 높은 조성의 LPG에 의하여 가소제는 많이 용출되었다. LPG에서 티올계 황화합물과 프로필렌이나 부타디엔 등의 불포화 탄화수소의 함량이 높아질수록 추출되는 가소제량은 증가한다. 반면에 큰 탄화수소일수록 고무로부터 추출된 가소제량은 적었다.

• 공업화학
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• 제5권3호
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• pp.419-424
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• 1994

금속공작유에 의해 발생하는 기름얼룩에 대하여 6종의 유지화합물(rapeseed oil, oleic acid, methyl oleate, oleyl alcohol, lauryl amine, lanolin)에 따른 영향을 조사하였다. 시험방법으로는 MIL-C-22235A의 방법을 사용하였으며 base oil(spindle oil; 1.5wt%의 황함유)에 유지화합물 10wt%와 항산화제 0.5wt%를 첨가시켜 도유용 sample을 만들었다. 시험결과 항산화제 중 B. T가 B. H. T.와 T. C. P보다는 기름얼룩 억제에 효과적이었으며, 산가는 기름얼룩 방지에 나쁜 영향을 미쳤다. 유지화합물의 화학구조에 의해 예견되는 바와 같이 oleic acid는 철이온과 반응이 가능하므로 시편에 심하게 기름얼룩을 발생시켰다.

• BMB Reports
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• 제29권5호
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• pp.429-435
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• 1996

To investigate the structure-antagonistic relationship of the cyclohexapeptide L-659,877, a selective NK-2 tachykinin receptor antagonist, seven analogues were chemically synthesized by a solid phase method. The agonistic and antagonistic activities of the analogues were evaluated by contraction assay using the smooth muscle of guinea pig trachea (GPT) containing the NK-2 receptor. It was shown that the aromatic ring of Phe at position 3 and the sulfur group of Met at position 6 in L-659,877 were essential for binding to the NK-2 receptor. Decrease in antagonistic activity of L-659,877 caused by substituting Leu for Nle at position 5 indicates that the ${\gamma}$ methyl group and side chain length of Leu plays an important role in its antagonistic action. Although the activity was slightly lower than L-659,877, cyclo $[{\beta}Ala^{8}]NKA(4-10)$ (analogue 1) showed potential antagonistic activity for the NK-2 receptor. It was confirmed that the expansion of the ring in L-659,877 by substitution of ${\beta}Ala$ for Gly at position 4 stabilized its conformation monitored by CD spectra. The results suggest that analogue 1 can be used as a new leader compound to design a more powerful, selective, and stable NK-2 receptor antagonist.

• 유통과학연구
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• 제16권2호
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• pp.53-65
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• 2018

Purpose - The purpose of this study is to investigate the effect of gamma - irradiation on the effluent from food distribution in the large agricultural and marine products market. This study will contribute to the distribution process as well as the agricultural and fishery distribution facilities. Research design, data, and methodology - In order to reduce the odor, the smell was examined in the anaerobic digestion process by irradiating gamma rays to the wastewater of mixed food discharged from a large restaurant. An odor determination panel list was constructed to determine if the odor was present in the air dilution drainage and the odor concentration was analyzed by instrumental analysis. Results - It was confirmed that the sulfur content increased gradually from 3 months. Ammonia decreased from 33.57ppm at the initial measurement to 4.12 ppm at the end of the experiment. Methane production was highest at 100kGy when exposed to gamma rays of 0-200kGy at pH 12. In other words, it is considered that gamma irradiation doses are most effective at 100kGy and are suitable for large capacity wastewater treatment facilities in terms of economic feasibility. Conclusions - In pre-treatment of compound food wastewater, gamma irradiation is most cost effective when examined at 100kGy. The economic efficiency of the pre-treatment method by gamma irradiation is much higher than the wastewater treatment in the large-scale agricultural and marine products distribution market.