• Korean Chemical Engineering Research
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• 제46권4호
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• pp.665-668
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• 2008

티타늄 함유 제올라이트 촉매 Ti-MCM-22를 이용하여 과산화수소를 산화제로 한 프로필렌 에폭시화반응을 수행하였으며, 반응 온도와 압력, 촉매량, 한계 반응물인 과산화수소의 농도, 산화프로필렌의 첨가, 용매 및 촉매 재생 효과를 조사하였다. Acetonitrile 용매 하에서 반응 실험을 수행한 결과, 99% 이상의 $H_2O_2$ 전화율과 100%에 근접하는 산화프로필렌 선택도를 보였다.

• 대한화학회지
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• 제55권6호
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• pp.978-982
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• 2011

In order to enhance the target action of chitosan-based drug, this paper firstly prepared phenylalanyl-glycylchitosan (Phe-Gly-CS) by grafting the key intermediate, bromoacetyl-phenylalanine (BA-Phe) onto chitosan. Then the target sugar molecule, lactobionic acid (LA), was grafted to Phe-Gly-CS and the topic compound lactobionic acid grafted phenylalanyl-glycyl-chitosan (Phe-Gly-CS-LA) was finally obtained in a yield of 78.8%. The product were characterized by FTIR, MS and 1H NMR. The preparing condition of BA-Phe was optimized as follows: the best pH was 10-11, the optimum temperature was $-4^{\circ}C$, the reaction time was 1.5 h.

• Bulletin of the Korean Chemical Society
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• 제29권12호
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• pp.2434-2440
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• 2008

The effect of sodium (Na) promotion was studied in the biphenol (BP) hydrogenation using various Pd/C catalysts. Different amounts of sodium metal were used for promotion with Pd/C and their effects on BP hydrogenation were observed. The promotion order was changed to compare the effect of the position of the promoter in relation to the palladium (Pd) metal on the catalytic activity and yield of the final product, bicyclohexyl-4,4'-diol (BHD). Pd/C catalysts prepared from different methods were also sodium-promoted and the changes of the reaction pathway according to the type of promoted Pd/C catalyst were compared.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.468-473
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• 1998

A mathematical model was developed for a continuous re-actor in which free radical polymerization of methyl methacrylate (MMA) occurred. Elementary reactions considered in this study were initiation, propagation, termination, and chain transfers to monomer and solvent. The reactor model took into account the density change of the reactor contents and the gel effect. A control system was designed for a continuous reactor using extended Kalman filter (EKF) based non-linear model predictive controller (NLMPC) to control the conversion and the weight average molecular weight of the polymer product. Control input variables were the jacket inlet temperature and the feed flow rate. For the purpose of validation of the control strategy, on-line digital control experiments were conducted with densitometer and viscometer for the measurement of the polymer properties. Despite the com-plex and nonlinear features of the polymerization reaction system, the EKF based NLMPC performed quite satisfactorily for the property control of the continuous polymerization reactor.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2005년도 추계학술대회 논문집
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• pp.386-388
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• 2005

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 추계학술대회
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• pp.211-213
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• 2001

• Environmental Engineering Research
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• 제12권5호
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• pp.203-210
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• 2007

Since the emissions composition from the household products have potentially been associated with health risks for building occupants, the chemical composition emitted from the products should be surveyed. The current study identified the emission composition for 42 liquid household products, using a purge-and-trap method. This evaluation was done by classifying the household products into five product classes (deodorizers, household cleaners, color removers, pesticides, and polishes). Nineteen compounds were chosen on the basis of selection criteria. The quality control program for purge-and-trap and analytical systems included tests of laboratory blank Tenax traps and blank water samples, and the determination of calibration equation, measurement precision, method detection limit (MDL), and recovery. The number of chemicals varied according to the product categories, ranging from 4 for the product category of bleaches to 12 for the product categories of air fresheners and nail color removers. For all product categories, the emission composition and concentrations varied broadly according to product. It is noteworthy that most household products emit limonene: 19 of 25 cleaning products; 5 of 6 deodorizers; 1 of 3 pesticides; 3 of 3 color removers; and 4 of 5 polishes. It was suggested that the use of household products sold in Korea could elevate the formation of secondary toxic pollutants in indoor environments, by the reaction of limonene with ozone, which entered indoor environments or might be generated by indoor sources such as electronic air cleaning devices and copying machines.

• 한국의류학회지
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• 제39권4호
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• pp.505-516
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• 2015

This study investigated difference of product interest and its relation to consumers' innate innovativeness according to gender as well as compared the perceptive construct of products between male and female consumers. A survey involving male and female college students was conducted in the Daegu and Gyeongbuk areas in December 2013. Subsequently, 400 responses were analyzed using descriptive statistics, correlations, independent sample t-test, reliability analysis, ANCOVA, and multidimensional scaling. Among 45 products, male respondents showed a significantly high degree of interest over 12 categories such as watches, desktop computers, cars, sports products, and video games compared to females. The female sample showed a significantly high degree of interest for 29 product categories such as clothing, movies, skin care shops, cosmetics, eating-out, teeth whitening, coffee, cameras, and performances compared to males. Innovative male consumers were interested in traveling, movies, clothing, eating-out, running shoes, and wallets; however, female consumers' innovativeness was significantly related to previously determined items of interest. Two dimensions explaining the male consumers' products perception construct were 'hard versus soft' and 'usual versus special'. Instead, female consumers' were 'special versus usual' and 'expressive versus functional'.

• 대한안전경영과학회지
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• 제14권4호
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• pp.59-70
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• 2012

This study compared data regarding industrial accidents and awareness level for beauty product safety for four main parts of beauty industry such as hair-care, nail-care, skin-care, and make-up. Major risk factors in beauty industry are dust, musculoskeletal disorders, and organic solvent of beauty product in order of percentage. The specific types of industrial accidents in beauty industry are mainly associated with musculoskeletal system such as cuts, sprain, and varicose vein. They are mainly compensated by personal budget. The awareness levels of chemical and heavy metal containment for beauty product by beauty industry employee were 77.2% and 59.1% respectively. Most employee confirmed only important items of labelling requirement of beauty product. Also, most employee did not understand MSDS(Materila Safety Data) for chemicals used in beauty industry. Only 38.1% of beauty industry employee has had safety education while most employee (73.6%) realized that they needed safety education. Also, safety education supervised by KOSHA(Korea Occupational Safety and Health Agency) was the most preferred. This study would be good basis for safe and healthy working environment of beauty industry employee.

• 한국환경보건학회지
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• 제45권4호
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• pp.321-325
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• 2019

The recent humidifier disinfectant disaster has caused a great change in our society and lead the Korean people to lose faith in the government and corporations. To overcome this mistrust, the government and corporations have undertaken certain efforts, including a voluntary agreement on consumer product safety. All the ingredients of a consumer product should be disclosed according to this voluntary agreement. There were also unexpected benefits occuring from this process. We found that the concept of corporate responsibility for product safety differed greatly among the various actors in Korean society. Corporations believed that a product could be considered safe if it contained no regulated substances. We have come to believe that this may be an important cause of the humidifier disinfectant disaster. The Korean government, corporations, and civil organizations have reached a consensus that it is a corporation's responsibility to evaluate the risks of products before they are introduced to the market. However, the limitations of these voluntary efforts are clear, and the legal system needs to be improved. We suggest that the concept of extreme recklessness should be introduced into regulations on product safety.