• 한국식품영양과학회지
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• 제33권9호
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• pp.1573-1579
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• 2004

단호박을 이용하여 새로운 가공제품을 개발하고자 여러가지 잇점을 줄 수 있는 삼투건조를 최적조건에서 처리하고 산업적으로 많이 사용되고 있는 열풍, 진공건조와 새로운 건조방법의 적용을 위해 선정한 냉풍건조를 행한 후 품질특성을 비교 평가하였다. 삼투처리 후 열풍, 진공, 냉풍건조된 단호박의 수분함량은 sucrose로 삼투처리한 경우가 모든 건조 방법에서 glucose 처리구보다 낮았으며, 건조방법에 따른 비타민 C의 함량은 glucose로 삼투처리 후 냉풍건조한 경우가 35.69 ㎎/100 g으로 가장 높게 측정되었다. 전반적으로 침지 용액에 따른 L, a, b값은 유사한 경향이었으며, 냉풍건조가 색도변화가 가장 작게 일어나 생단호박의 색상과 유사하였다. 건조 단호박의 표면구조는 삼투용액과 건조방법에 따라 상이하였는데, 삼투처리 후 냉풍건조된 단호박을 제외하고 열풍 및 진공건조된 단호박의 조직 손상이 크게 나타났다. 건조방법 및 건조시간에 따른 수분함량과 비타민 C함량을 살펴보면 수분함량의 경우 건조효율성을 고려할 때 sucrose로 삼투처리 후 진공건조한 단호박이 가장 우수하였으나, 비타민 C함량에서는 glucose로 삼투처리 후 냉풍건조한 단호박이 가장 양호하였다. 삼투용액에 따른 건조방법별 건조속도는 sucrose로 삼투처리한 단호박의 건조속도가 glucose 처리구보다 빠름을 알 수 있었다.

• 분석과학
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• 제25권6호
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• pp.395-401
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• 2012

본 연구에서는 PVC 제품에 잔류하는 염화비닐 단량체(VCM)에 대한 정량분석방법을 제시하였다. 용출용매의 경우, 에탄올, THF, 아세톤에서 유사한 추출효율을 나타내었으나, 노말헥산을 이용한 경우에는 상대적으로 낮은 추출효율을 보였다. 분쇄 PVC 시료에 VCM 표준용액을 주입한 분석시료에 대한 VCM 함유량 측정 결과, GC/MS를 이용한 직접주입법이나 헤드스페이스법 모두 양호한 결과를 나타내었다. PVC 제품의 중간물질인 스펀지에서의 VCM 분석과 관련하여 5 개 시험전문기관의 시험소간 비교시험 결과, 각 시험소간 결과 편차가 크지 않은 것으로 나타나 본 연구에서 제시한 전처리 및 분석방법에 대한 플라스틱 제품내의 VCM 정량방법이 유효한 것으로 판단되었다.

• Toxicological Research
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• 제34권1호
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• pp.49-53
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• 2018

Cyclohexanone ($C_6H_{10}O$, CAS No. 108-94-1) is a colorless oily liquid obtained through the oxidation of cyclohexane or dehydrogenation of phenol. It is used in the manufacture of adhesives, sealant chemicals, agricultural chemicals, paint and coating additives, solvent, electrical and electronic products, paints and coatings, photographic supplies, film, photochemicals, and as an intermediate in nylon production. Owing to the lack of information on repeated inhalation toxicity of cyclohexaone, in this study, we aimed to characterize the subacute inhalation toxicity. B6C3F1 mice were exposed to 0, 50, 150, and 250 ppm of cyclohexanone for 6 hr/day, 5 days/week for 4 weeks via whole-body inhalation in accordance with the OECD Test Guideline 412 (subacute inhalation toxicity: 28-day study). Mortality, clinical signs, body weights, food consumption, hematology, serum biochemistry, organ weights, as well as gross and histopathological findings were evaluated between the control and exposure groups. No mortality or remarkable clinical signs were observed during the study. No adverse effects on body weight, food consumption, hematology, serum biochemistry, and organ weights, gross or histopathological lesions were observed in any male or female mice in any of the exposure groups, although some statistically significant changes were observed in organ weights. We concluded that no observable adverse effect level (NOAEL) is above 250 ppm in mice exposed to cyclohexanone for 6 hr/day for 5 days/week.

• 전기화학회지
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• 제12권1호
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• pp.54-60
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• 2009

The redox characteristics of 2-arylaldehydehydrazono-3-phenyl-5-substituted-2, 3-dihydro-1, 3, 4-thiadiazoles (1a-h) have been investigated in nonaqueous solvents such as 1, 2-dichloroethane (DCE), dichloromethane (DCM), acetonitrile (AN), Tetrahydrofuran (THF), and dimethylsulfoxide (DMSO) at platinum electrode. Through controlled potential electrolysis, the oxidation and reduction products of the investigated compounds had been separated and indentified. The redox mechanism had been suggested and proved. It had been found that all the investigated compounds were oxidized in two irreversible one-electron processes following the well-known pattern of The EC-mechanism; the first electron loss gives the corresponding cation-radical which is followed by proton removal from the ortho-position in the N-phenyl ring forming the radical. The obtained radical undergoes a second electron uptake from the nitrogen in the N = C group forming the unstable intermediate (di-radical cation) which undergoes ring closure forming the corresponding cation. The formed cation was stabilized in solution through its combination with a perchlorate anion from the medium. On the other hand, these compounds are reduced in a single two-electron process or in a successive two one-electron processes following the well known pattern of the EEC-mechanism according to the nature of the substituent; the first one gives the anion-radical followed by a second electron reduction to give the dianion which is basic enough to abstract protons from the media to saturate the (C = O) bond.

• 한국인터넷방송통신학회논문지
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• 제12권6호
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• pp.207-213
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• 2012

B2C형 소셜커머스는 IT기술 발달과 폐쇄형 거래형태를 개방형 형태로 변화하고 있으며 또한 중간유통을 획기적으로 줄임으로써 소비자에게 유통비용을 제거하여 파격적인 가격에 상품을 제공하고 있다. 시대의 흐름에 따라 기업 간 거래에서는 수많은 유통 채널을 통해 PRM(Product Relationship Management) 관리의 어려움과 신속하게 새로운 제품을 홍보하고 관리하는데 상대적으로 어려움을 겪고 있다. 제품을 유통 및 소비하는 기업들을 한곳에 모을 수 있는 플랫폼 제공을 통하여 B2C 기반의 소셜커머스를 롤 모델로 하여 운영 할 수 있는 플랫폼 제공이 필요하다. 또한 B2C 기반의 소셜커머스와 달리 B2B의 경우는 구매에 따른 결제 대금을 일시불로 지급하지 않고 할부 등 기간을 두고 지불하는 결제 시스템연동이 필수적인 요소이다. 본 연구에서 소개하는 B2B 거래를 위한 소셜커머스는 B2B 거래의 문제점을 해결하고 새로운 시장을 개척하여 효과적인 B2B 거래를 제공하고 관련 산업인 기업 간 전자결제 시장의 확대를 가져올 것이다. 향후 연구 분야는 본 연구에서 제안하는 모델에 대한 실증적 연구를 통해 본 제안 모델이 시장에 정착할 수 있다는 것을 연구하는 것이다.

• 한국응용과학기술학회지
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• 제24권4호
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• pp.436-443
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• 2007

Anaerobic reductive dehalogenation of perchloroethene (PCE) was studied with lactate as the electron donor in a continuously stirred tank reactor (CSTR) inoculated with a mixed culture previously shown to dehalogenate vinyl chloride (VC). cis-1,2- dichloroethene (cDCE) was the dominant intermediate at relatively long cell retention times (>56 days) and the electron acceptor to electron donor molar ratio (PCE:lactate) of 1:2. cDCE was transformed to VC completely at the PCE to lactate molar ratio of 1:4, and the final products of PCE dehalogenation were VC (80%) and ethene (20%). VC dehalogenation was inhibited by cDCE dehalogenation. Propionate produced from the fermentation of lactate might be used as electron donor for the dehalogenation. Batch experiments were performed to evaluate the effects of increased hydrogen, VC, and trichloroethene (TCE) on VC dehalogenation which is the rate-limiting step in PCE dehalogenation The addition of TCE increased the VC dehalogenaiton rate more than an increase in the $H_2$ concentration, which suggests that the introduction of TCE induces the production of an enzyme that can comtabolize VC.

• 복식문화연구
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• 제24권1호
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• pp.41-53
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• 2016

The purposes of this study was to identify fashion shoppers' perceived risk and satisfaction while shopping at overseas online shopping malls based on their internet shopping values. A self-administered questionnaire was used for data collection and an internet survey was conducted from April 12~15, 2015. Most consumers purchased one or two fashion items at overseas online malls directly, motivated by low prices, and spent 200,000~400,000 won during the last one year. The factors of consumers' internet shopping values were information, hedonics, and practicality. Factors of perceived risk were delivery and refund, price and approval, and product and shopping mall. Consumers were divided into three categories: heavy pursuit shoppers, intermediate shoppers, and uninformed shoppers based on their internet shopping values. Heavy pursuit shoppers were primarily female; they spent more, felt a deeper patronage with overseas online shopping malls and their perceived risk regarding delivery and refund was higher than the other shoppers. The group of uninformed shoppers were primarily male. They spent less, had low patronage with overseas online shopping malls, and their perceived risk regarding delivery and refund was lower than other shoppers. Overall satisfaction was positively affected by information provided while shoppers were surfing the overseas online shopping malls and practicality. Satisfaction was negatively affected by perceived risk regarding price and approval and difficulty in finding specific products while shopping at overseas online shopping malls.

• ALGAE
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• 제35권2호
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• pp.177-187
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• 2020

Cyanobacteria have been widely reported to produce a variety of UV-absorbing mycosporine-like amino acids (MAAs). Herein, we reported production of the unusual MAA, mycosporine-glycine-alanine (MGA) in the cyanobacterium Sphaerospermopsis torques-reginae ITEP-024 using a newly developed UHPLC-DAD-MS/HRMS (ultra-high performance liquid chromatography-diode array detection-high resolution tandem mass spectrometry) method. MGA had previously been first identified in a red-algae, but S. torques-reginae strain ITEP-024 is the first cyanobacteria to be reported as an MGA producer. Herein, the chemical structure of MGA is fully elucidated from one-dimensional / two-dimensional nuclear magnetic resonance and HRMS data analyses. MAAs are unusually produced constitutively in S. torques-reginae ITEP-024, and this production was further enhanced following UV-irradiance. It has been proposed that MAA biosynthesis proceeds in cyanobacteria from the pentose phosphate pathway intermediate sedoheptulose 7-phosphate. Annotation of a gene cluster encoded in the genome sequence of S. torques-reginae ITEP-024 supports these gene products could catalyse the biosynthesis of MAAs. However, addition of glyphosate to cultures of S. torques-reginae ITEP-024 abolished constitutive and ultra-violet radiation induced production of MGA, shinorine and porphyra-334. This finding supports involvement of the shikimic acid pathway in the biosynthesis of MAAs by this species.

• 대한환경공학회지
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• 제35권6호
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• pp.389-393
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• 2013

본 연구의 목적은 유류로 오염된 토양으로부터 분리된 고효율 분해균주에 의한 xylene 분해특성을 조사하고 분해과정을 밝히는 것이다. P. putida BJ10에 의해 mineral salts medium (MSM)배지내에서 24시간 배양 후 제거율은 o, m, p-xylene 각각 94, 90, 98%였으며 3% 이하의 대조군과 명확한 차이를 보였다. 또한 유류로 오염된 토양내에서의 9일 경과 후 xylene 제거율은 유류 분해균주 주입구에서 66%였으며 무처리 일반토양에서 32%, 멸균 토양에서 8%로서 P. putida BJ10에 의한 유효성을 확인할 수 있었다. 또한 시간경과에 따른 대사산물을 분석한 결과 o-xylene의 분해 경로에서는 6시간 경과 후 3-methylcatechol, 24시간 경과 후 o-toluic acid 가 분해산물로서 검출되어 최종산물로서의 o-toluic acid 가 확인되었으며 중간산물의 변환과정은 기존 발표된 연구들과 다소 다른 결과를 나타내었다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제1회 추계심포지움 and 제2회 생리분자과학연구센터워크숍
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• pp.17-20
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• 1993

As a step toward a more complete understanding of the molecular actions of TNF, we prepared a cDNA library from TNF-treated human FS-4 fibroblasts and used differential hybridization to identify cDNA clones corresponding to mRNAs enriched in TNF-treated eells. In Quiescent FS-4 cells n induces an increase in the level of some mRNAs within 20 to 30 min. Some of these immediate-early response mRNAs are elevated only transiently for about 30 to 120 min, e. g., c-fos and c-myc (Lin and Vilcek,1987) or the transcription factor IRF-1 (Fujita et al.1989). Such immediate-early gene products may be important for the activation of other genes, but their transient induction suggests that they are not the actual effector molecules responsible for the phenotypic changes induced by TNF. We chose a 3-h incubation with W because we were seeking cDNAs corresponding to messages that are more stably elevated after TNF treatment. Indeed, the results shown in Figure 8 and 9 indicate that all of the mRNAs corresponding to the eight TSG cDNAs isolated remained significantly elevated after 16h of continuous treatment with TNF, and their kinetics of induction were clearly different from those of the immediate-early response mRNAs such as c-fos, c-myc or IRF-1. Nevertheless, only the induction of TSG-21 (collagenase) and TSG-27 (stromelysin) nNAs was completely inhibited by cycloheximide and the induction of TSG-37 (metallothionein-II) was reduced in the presence of this inhibitor of protein synthesis. Induction of the other five TSG mRNAs by TNF was completelyresistant to cycloheximide, suggest ins that no protein intermediate is needed for the upregulation of these mRNAs.