• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.66-74
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• 1992

A method for the multiresidual simultaneous analysis of 11 thiocarbamates was studied using HPLC. Thiocarbamate in Chinese cabbage was analyzed in the order of extraction, partition, and cleanup in their optimum condition. Acetone was chosen as an extracting solvent. As a partitioning solvent, the mixture of 50% methylene chloride and petroleum ether containing extremely small water content showed good recoveries of thiocarbamate from the water layer. Partition efficiency was affected by pH of the water layer; it remained almost constant under the acidic and neutral condition while decreasing under the basic condition. The comparison done in cleanup step showed that the column chromatographic method is superior to the treatment of coagulating reagent. As an absorbent, the mixture of charcoal, magnesia, and celite with the ratio of 1 : 2 : 4 gave better recoveries and also effectively removed chlorophyll. Over the total procedure, the average recoveries for thiocarbamates in Chinese cabbage were 91% at about 2 ppm fortification level within the relative standard deviation of 8%, and the minimum detection limit (MDL) was 2.2${\sim}$9.3 ng.

• Journal of Conservation Science
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• v.29 no.2
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• pp.127-138
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• 2013

Plastic, widely used as a material for contemporary art, get damaged as directly exposed to temperature, humidity, ultra violet, etc. And it is very quickly damaged in early time, once damaged, it can't recover into original state. But like this characteristics, there is a few advanced research in Korea. So this study deal with a rising value of plastic artifacts in other country, United Kingdom and France, current conservation state, identification and cleaning method. Also 5 types of cleaners(distilled water, ethanol, acetone, eraser) and adhesives(cyanoacrylate, epoxy, acrylic, chloroprene rubber) were evaluated by produced plastics(PVC, PE, PP, PS, PU). As a result of experiment, ethanol and acetone that were previous evaluated in other research performed in other country are the best cleaner. Result of degradation after adhesive, cyanoacrylate and epoxy resin showed better performance and stability. As a basic research, this study is expected that can be used in future researches.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.36-44
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• 2002

GC-l00X is non-corrosive alkaline ionic water (pH 12). It is composed of hydroxyl radicals and supplemented with xylitol. Its antimicrobial activity was examined against 6 major food-borne pathogens; Staphylococcus aureus FRI 913, Salmonella enterica serova Enteritidis ATCC 13076, S. enterica serova Typhimurium Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894 and Pseudomonas aeruginosa KCTC 1637 at three different temperatures (4$^{\circ}C$, $25^{\circ}C$ and 36$^{\circ}C$) with or without an organic material (2% yeast extract), respectively. The antimicrobial activities showed over 4 log-reductions (1.0$\times$10$^4$CFU/ml reduction) against all pathogens reacted at 37$^{\circ}C$ for 3 hours in the absence of the organic material. The activities showed same results when GC-l00X was diluted with same volume of distilled water or standard hard water (CaCO$_3$300 ppm). Its antimicrobial activity was more effective and quicker in Gram-negative bacteria than Gram-positive bacteria. Its washing efficacy against E. coli O157:H7 exposed to the surfaces of tomatoes (grapes) was compared with that of the other sanitizers such as other kitchen synthetic detergent and 100-ppm chlorine water. For the toxicological evaluation of the sanitizers, viable counts of E. coli O157:H7 penetrated into the core of tomatoes after washing products were also compared. The result revealed that GC-100X stock solution and its 5% diluted solution had similar washing effects to 100-ppm chlorine water and more effective than the other kitchen synthetic detergent. This result indicated that GC- l00X had antimicrobial activity and no toxicological side effects, therefore, could be useful for a new sanitizer to use in flood safety and kitchen hygiene.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.26-30
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• 2008

Polycyclic Aromatic Hydrocarbons(PAHs) contamination arises from several source including processing of food(smoking, direct drying, cooking) and environmental contamination of air, water or soil. A red ginseng is produced by steaming the root followed by drying. The methodology involved extraction with n-hexane and washing with water, clean-up on Sep-Pak Florisil Cartridges and determination by HPLC/FLD. The mobile phase was a mixture of acetonitrile and water in 8:2 by the isocratic elution and the excitation wavelength of fluorescence detector was 294 nm and its emission wavelength was 404 nm. The average recovery was about 105% and the relative standard deviation was 0.5. The levels of benzopyrene in the selected red ginseng beverage samples were not detected.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.5
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• pp.840-851
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• 2021

In this study, we used a chemiluminescence reaction to investigate the removal effect of pet soil, such as dog blood, urine and feces. The soiled fabrics were washed with a standard laundry course of 30℃ and a washing time of 30 min and a pet care laundry course of 40-60℃ and a washing time of 100 min. The detergency was evaluated by the surface reflectance and chemiluminescence reaction (bloodstain detection by luminol test and urine-stain and feces-stain detection by UV blacklight test) before and after washing. The surface reflectance results did not show any difference in detergency for both courses, whereas the chemiluminescence reaction did. The detergency of the pet care course compared to the standard course was 101% according to the surface reflectance and 120% according to the chemiluminescence reaction. Therefore, residual stains not detected by surface reflectance can be evaluated through chemiluminescence reaction, and it was confirmed that pet stains can be managed more hygienically by washing for a long time at a high temperature.

• Journal of Food Hygiene and Safety
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• v.19 no.2
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• pp.66-73
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• 2004

This study was performed to assess the microbiological quality of kimbap (rice balls rolled in laver) prepared in two conditions (normal condition or clean, sanitized condition) and to support a practical application to identify critical control points (CCPs) in the preparation and cooking processes of kimbap. Kimbap, raw materials of kimbap, utensils (knives, cutting board, and kimbal which is made of bamboo), and hands of food handlers were examined microbiologically. Airborne microbes in the kitchens were also evaluated. Escherichia coli, Salmonella and Staphylococcus aureus were not detected in all samples. The aerobic bacteria and coliform bacteria levels of all samples in clean, sanitized condition were much lower than those in normal condition. More aerobic bacteria and coliform bacteria were counted in unheated raw materials of kimbap than in heated raw materials. In both conditions, the levels of airborne microbes of the kitchens were satisfactory. The aerobic bacteria and coliform bacteria of kimbap prepared in clean, sanitized condition were one hundredth levels of those of kimbap prepared in normal condition. However, fecal coliforms were detected even in the kimbap prepared in clean, sanitized condition. The results indicate that microbiological contamination of kimbap may be mainly originated from the contaminated unheated raw materials, utensils, and hands of food handlers, and also possible cross-contamination during preparation. The CCPs for kimbap preparation and cooking were handling of unheated raw materials, cleaning and sanitizing utensils, and hand washing of food handlers.

• Tuberculosis and Respiratory Diseases
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• v.63 no.3
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• pp.294-298
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• 2007

Pulmonary alveolar proteinosis is a rare disorder that is characterized by the abundant accumulation of surfactant-derived material within the alveolar spaces and distal bronchioles. Although the findings of homogenous ground-glass opacities overlaid by thickened septa, which form a "crazy paving" pattern on high-resolution computed tomography, can assist in making a diagnosis, a lung biopsy is usually required. This disorder has a variable clinical course, from spontaneous resolution to respiratory failure and death. While a whole lung lavage has been the standard treatment since the early 1960s, GM-CSF therapy has been attempted based on the recently suggested pathogenetic mechanism. We report a case of pulmonary alveolar proteinosis that resolved spontaneously after an open lung biopsy.

• Journal of Sensor Science and Technology
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• v.12 no.1
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• pp.34-43
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• 2003

In this study, we implemented the measurement of pH, $pO_2$, $pCO_2$ of the arterial blood on a portable blood gas analysis system. This system is consist of two parts of hardware and software. The hardware part is divided into a fluidic mechanism and an electronic circuit unit. The system program is composed of operating, washing, correcting, and measuring routines. Both of 1-point and 2-point calibration schemes were used to enhance the accuracy of the measurement. In order to evaluate the performance of the developed system, we measured and performed statistical analysis on the characteristics of the sensing electrode response. As a result, coefficient variation was within 1.12, and maximum error was within 1.298%. We confirmed development possibility of portable blood gas analyzer.

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.29-36
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• 2009

The authors of this study have developed a robot milking system composed of a multi-articular manipulator, a teat-cup attachment system, and an image processing system. In order to verify the efficacy of this system, we have conducted a performance analysis and measurement experiment of milk yield, using dairy cattle. It was concluded that teat recognition using the image processing system, teat-cup attachment, and detachment system did not binder milking. The milking yield of the robot milking system was analyzed based on a lactation curve. As a result, it was determined that the use of a robot milking system had no significant effects on milking yields. The robot milking system described in this study is designed specifically with a focus on teat-cup attachment and detachment performance, as well as the effect of these factors on milking yield. In the future, in-depth studies regarding the washing of the teats prior to milking, teat massage, pre-treatment and post-treatment processes after milking, and disinfection processes shall be conducted, in order to render this system feasible for use in an actual milking parlor.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.79-79
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• 2018

마그네슘은 나트륨, 알루미늄과 함께 지구상에서 가장 풍부한 금속 중 하나로서 밀도가 약 $1.74g/cm^3$으로서 구조용 금속재료 중 가장 가볍고 우수한 비강도를 지니고 있으며, 우수한 열전도도, 전기전도도, 전자파 차폐능을 지닌다. 최근 마그네슘 및 그 합금은 항공기, 자동차, 전자제품, 기계류 및 생활용품 등에 쓰이고 있으며, 사용량 및 적용범위가 매년 급격히 증가되고 있는 추세이다. 그러나 마그네슘합금은 매우 낮은 표준 환원전위와 치밀하지 못한 표면 산화막으로 인하여 부식에 대한 저항성이 매우 취약하다는 한계를 가지고 있다. 따라서 마그네슘합금의 표면처리 가운데 부식에 대한 저항성을 보완할 수 있는 방법은 활발한 마그네슘합금의 응용에 필수적이다. 이러한 마그네슘합금의 내식성을 향상시키고자 전기화학적 플라즈마 전해 산화처리 (Plasma Electrolytic Oxidation)를 하게 되는데, 아노다이징, 화성피막처리 등 과 같은 기존의 산업적 표면처리 방안으로는 불가능한 수준의 표면경도를 확보할 수 있을 뿐만 아니라 두꺼운 산화피막 형성을 통해 이들 합금이 가진 기본적 취약점인 내식성 문제를 보완할 수 있는 장점이 있지만, 다공성 산화피막 형성만으로 기대할 수 있는 내식성 향상 효과가 매우 크지는 못하다. 따라서 다공성의 양극산화피막의 단점, 즉 다공성 물질로 부식성 물질의 이동을 허용할 수 있는 공간을 가지는 구조를 개선시킬 수 있는 추가적인 처리를 필요로 한다. 본 연구에서는 발수성 표면처리를 이용하여 다공성 구조물의 표면이 물에 대한 저항성을 가지도록 함으로써 초발수성 표면을 구현하고자 하였다. 이러한 방법은 기존의 후처리 방법인 봉공처리로는 얻을 수 없었던 다공성 구조물로의 부식성 물질의 침투를 억제할 수 있었으며, 상당한 수준의 내식성 향상 효과를 보여주었다. 또한 물에 대한 반발성은 표면에 물의 이동성을 높이는 효과를 보여주며 이로 인하여 자기세척 효과도 보여주었다.