• Journal of Radiation Protection and Research
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• v.4 no.1
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• pp.14-20
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• 1979

For accurate and easily shielding irregular shaped organ, its minimized penumbra region and a low melting point alloy 'Lead Y' and synchronizing instrument have been developed. The 'Lead Y' is the quaternary eutectic alloy and it is composed of Lead 30.0% Tin 11.5% Bismuth 48 5% Cadmium 10.0% The density of its at $22^{\circ}C$ is $9.8g/cm^3$ and the melting temperature has $40^{\circ}C\;to\;68^{\circ}C$. The thickness of 'Lead Y' for perfect shielding of Co-60 gamma ray and LINAC 10MeV x-ray is 6cm and 7cm respectively. The 'Lead Y' shielding block is casted directly on the styrofoam from which is cut with hot wire of synchronizer device. The special features and advantages of the Lead Y shielding block could be summarized as follows; 1. The shielding block for radiotherapy is rapidly processed only with boiling water and styrofoam. 2. It is not injure one's health and not danger of a fire, because of not generating of any metals vapor and evil smelling. 3. It is very effective to minimize secondary penumbra for the protection of healthy tissue from unnecessary ionizing radiation regardless of the magnification source to skin distance. 4. The HVL of the Lead Y is 1.2cm for Co-60 gamma ray and it's shielding effect is almost same as the pure lead block. 5. The hardness of Lead Y is 1.5 times higher than lead block. 6. It's reavailability is higher than lead block and then one block of Lead Y is reavailable about 30 to 40 times. 7. It is usefull for shielding of x-ray, gamma ray, beta-ray, electron and neutron radiation. 8. The materials for Lead Y are easy to acquire with reasonable price and tractable.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.632-637
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• 2017

The vehicle lubricant occupies upto 35% in a total lubricant market and engine oil occupies upto 77% in the vehicle lubricant market in Korea. A suitable quality management of the circulating engine oil is necessary for driver and engine protection. But, KS and synthetic engine oil products (involved over 30% synthetic oil) are exempt to any quality management under Petroleum and Alternative Fuel Business Act. It is also known that synthetic oils such as PAO (poly alpha olefin) have excellent properties and performance like anti-wear, varnish control and oxidation stability than those of mineral oils. For this reason, PAO has been used for an engine oil, rotary screw and reciprocating compressor in addition to heavy duty and other extreme service applications. In this study, our research group analyzed the chromatogram pattern for the mineral oil, PAO and mineral oil involved a typical ratio of PAO using SIMDIST (simulated distillation). In the SIMDIST chromatogram, the mineral oil showed a broad peak, while PAO showed a sharp typical peak. Also the oil with a large viscosity grade exhibited a long retention time due to the heavy molecular weight and high boiling point. In particular, the blended mineral oil with 20% PAO sample showed a distinctly different pattern compared to that of using the conventional mineral oil. For monitoring PAO contents in distributing engine oils, we analyzed the SIMDIST for 27 kinds of engine oils which were popularly sold in Korea. The analytic results indicate that all kinds of engine oils showed that PAO contents were below 20% in engine oil products. Moreover, the PAO titled product was found to have a small amount of PAO. Thus, we conclude that the related laws for the proper quality management of synthetic oils are needed to be established.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.363-368
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• 2006

This study selected the optimal catalyst for the process of producing $C_9$-alcohol by hydrogenating $C_9$-aldehyde, and carried out an experiment in order to establish the operating condition for maximizing the yield of $C_9$-alcohol. The BET surface area and the specific area of copper were most excellent in $CuO/ZnO/Al_2O_3$ (60:30:10 wt％) catalyst produced using acetate as a precursor of copper and $Na_2CO_3$ as a precipitant, and the catalyst also showed the highest performance in $C_9$-aldehyde hydrogenation. Using a trickle bed reactor loaded with optimized catalyst, we attained 94.1 wt％ yield of $C_9$-alcohol under the condition of $175^{\circ}C$, 800 psi and $WHSV=3hr^{-1}$. According to the result of comparing with other catalysts used in the hydrogenation of aldehyde, the catalyst showed similar performance to that of Ni/kieselghur and higher than that of $Cu-Ni-Cr-Na/Al_2O_3$ and $Ni-Mo/Al_2O_3$. According to the result of examining the stability of the catalyst through a long-term catalysis test, the yield of $C_9$-alcohol decreased slowly after around 72 hours due to the increasing production of high boiling-point byproducts.

• The Korean Journal of Food And Nutrition
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• v.26 no.1
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• pp.60-65
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• 2013

This study investigated the quality changes of French fries when cooked under a lower pressure than the ambient atmosphere. This was derived from the concept of boiling point depression of water under reduced pressure. The pressure during the frying process was controlled at measures of 760 mmHg, 560 mmHg, 360 mmHg, or 160 mmHg. The frying apparatus was manufactured to cook foods up to $200^{\circ}C$ and to have a valve to control the pressure. French fries were cooked at $180^{\circ}C$ for 4 minutes. After each pressure level was achieved, the French fries were dipped into a frying oil bath and cooked for 4 minutes. The quality changes, including moisture content, starch gelatinization, textural and sensory properties of the French fries were measured. The moisture contents were decreased at all 4 pressure levels after frying. Starch gelatinization was not significantly different among the samples. The hardness of French fries cooked at 160 mmHg was the best. In addition, the sensory properties including brown color, taste, and crispiness of French fries cooked at 160 mmHg was the best. The overall preference was higher when the frying pressure was lower.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1169-1180
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• 2005

First, I read all the materials, including Dongeuibogam(Encyclopedia Medica Koreana), classical writings on Lacca sinica exsiccata, herbal writings on lacquer poison, and herbal books on how to treat lacquer poison. And then after 1 examined all the details on qi and taste of Lacca sinica exsiccata, its efficacy, detoxification, lacquer poison, and its effects on body symptom, 1 got the following results. The order of frequency that Lacca sinica exsiccata is used in Dongeuibogam is pressure-feeling, blood circulation, and insect biting. Its way of intake is not so much through herb-boiling or powdered medicine as through hand-made pills. When medicine is used in the form of pills, the Lacca sinica exsiccata is more included among other ingredients. When old doctors treated pressure-feeling in the chest, they mixed up other herbs, with not putting more emphasis on the efficacy of lacquer 010 doctors believed that toxicity of Lacca sinica exsiccata is not having its own poison, but having biased dominance in the use of its qE and taste. The way or detoxification or Lacca sinica exsiccata is used in the order of crab-boiled water, egg, Xanthoxylum piperitum, Perilla frutescens, Astar tataricus, a weeping willow, iron-tempered water, and Allium toberosum. Special point in detoxificating lacquer poison is that they used medicines for well-ciruculating pulmonary stream, medicines for promoting to urinate or discharge by helping large colons to move, medicines for making the lacquer scar small, medicines for helping digest, and medicines for improving vessel function in the poisoned area. With the above results, the more profound study, based on the crab-boiled water and egg, is expected to go on to increase the effect on the one hand, and to make the new way of lessening or removing the toxicity of lacquer with more safe use on the other hand.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.435-441
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• 2008

In this paper, we investigated the electrical properties of triisopropylsilyl (TIPS) pentacene organic thin-film transistor (OTFT) depending on solvent type. We spin coated TIPS pentacene by using chlorobenzene, p-xylene, chloroform, and toluene as solvents. Fabricated OTFT with chlorobenzene shows field-effect mobility of $1.0{\times}10^{-2}cm^2/V{\cdot}s$, on/off ratio of $4.3{\times}10^3$ and threshold voltage of 5.5 V. In contrast, with chloroform, the mobility is $5.8{\times}10^{-7}cm^2/V{\cdot}s$, on/off ratio of $1.1{\times}10^2$ and threshold voltage of 1.7 V. Moreover we measured the grain size of each TIPS pentacene solvent by atomic force microscopy (AFM). From these results, it can be concluded that a solvent with higher boiling point results in better electrical characteristics due to large grain size and high crystallinity of TIPS pentacene layer. In this paper TIPS pentacene with chlorobenzene shows the best electrical properties.

• The Journal of Internal Korean Medicine
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• v.10 no.1
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• pp.65-80
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• 1989

About Oui-Ga-Sil(胃家實) in order to considerate the contents recorded in Nai-Gyung Sang-Han-Lon and latter literature, definition, etiopathology, syndrome, differential diagnosis, therapy, Prognosis and prevention were classified. And the results were as follows: 1. Oui-Ga(胃家)was a term which indicated the whole digestive system such as stomach, small intestine, large intestine, rectum and anus. Sil(實)could be defined as the peculiar concept pertaining to the acute and last stage which was invaded to inside bowels because of abundance with evil influence. 2. Eliology of Oui-Ga-Sil was abunt gastric fever originally, injured mucus because of mistreatment, the invasion to inside of outside evil influence through meridian. Pathology was the opening and shutting appearance of gastric abundance with intestinal emptiness, and intestinal abundance with gastric emptiness, Oui-Ga-Sil could be occurred because of gastric abundant dryness and splenic humidifying capacity decrease. 3. Symptom of Oui-Ga-Sil was classified as for the sunlight outside syndrome and the inside abundant syndrome. The sunlight outside syndrome was body fever, sweating, no chilling, on the contrary hatred of fever. The chief complaint of inside abundant syndrome was daily fever, talking in delirium, hand and foot sweating, abdominal distention, difficult defection and those could be pertained to sunlight bowel syndrome. 4. Diagnostic views of Oui-Ga-Sil were that pulse was descending abundant large strong and smooth quick, a coated tongue was yellow, deep yellow, old yellow, thick, scorching dry rough or gray black. On abdominal diagnosis, pressing by hand, patient was conscious of pain, excessive pain, rejection against press, impossible press or intermittent abdominal pain and bowel cutting pain without press. 5. Differential diagnosis was that the sunlight of Nai-Gyung-Fever-Theory was outside desease making meridian the prime object, Baik-Ho-Tang syndrome was making figureless abundant fever the pivotal point. And important differential standard of splenic shrink syndrome was that a daily fever, an irritation with fever were not occurred. 6. Theory of Oui-Ga-Sil was that Seng-Gi-Tang classes had been used in attacking downward or making balance, and moxibustion on Jung-Wan, honey boiling induction theory had been also used. Attacking downward therapy was invigorating method to preserve mucus, and if mucus had been exausted with complicating emptiness prognosis had been appeared badly. 7. Preventing from Oui-Ga-Sil diet by rule, fitness to cold and warmth may be needed to prevent outside evil influence attack and inside evil influence occurrence. Prudence with being very busy, fatigue, wine and woman may be also needed not to be an injury to splanic and gastric spirit.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.510-515
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• 2008

Microwave energy was applied to the extraction of functional catechins from grape seed. The solvent, absolute ethanol, reached the boiling point when exposed for less than 3 min microwave treatment at 100 W. The effects of independent variables in microwave-assisted extraction (MAE), including microwave power (0-160W, $X_1$), ethanol concentration (0-100%, $X_2$) and extraction time (1-5 min, $X_3$), were investigated on each response variable ($Y_n$), and the contents of catechin and its derivatives were determined via response surface methodology, thereby allowing us to predict their optimal extraction conditions. The predicted maximal values of (+)-catechin, procyanidin $B_2$, (-)-epicatechin, and (-)-epicatechin gallate were 137.99, 72.78, 222.38, and 9.59 mg%, respectively, under different MAE conditions. The predicted extraction conditions for maximum catechin responses were as follows: 104.10 W of microwave power, 45.35% of EtOH, and 4.89 min of extraction time for (+)-catechin (137.99 mg%), 133.16 W, 46.16% and 4.49 min for procyanidin $B_2$ (72.78 mg%), 136.00 W, 41.37% and 4.39 min for (-)-epicatechin (222.38 mg%), 143.20 W, 37.51% and 1.88 min for (-)-epicatechin gallate (9.59 mg%), respectively. The contents of (+)-catechin, procyanidin 1B2 and (-)-epicatechin in MAE were similarly influenced by three independent variables, whereas (-)-epicatechin gallate was influenced less profoundly by ethanol concentration and extraction time.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.63-75
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• 2007

A survey on sanitary management at 98 food service institutions located in Jeollabuk-Do were conducted. Food service institutions included 13 hospitals, 38 schools, 40 enterprises, and 7 others. The sterilization in boiling water was used for disinfection of tableware, spoon and chopsticks, and dish towel. Cooking kit, refrigerator, chopping board, and knife were sterilized with disinfectant. Frequency of sanitary training program on employees was 56.1% for 1 time/month, 12.2% for 2-3 times/month, and 11.3% for 1 time/week. Preparing ratio of defrosting, warehouse and rest room, and washing and sterilization diary were 73.8, 60.5, and 54.5%, respectively. However, checking ratio of environments (9.5%), personal sanitation (10.8%), and sanitary training program diary(8.4%) were low. Major obstacle factors on the introduction of Hazard analysis critical control point (HACCP) system into food service institutions were lack of equipment and facilities (54.1%) and lack of understanding and data on HACCP system (17.3%). Therefore, in order to reduce the outbreak of food-borne diseases increasing frequency, we estimated that the introduction of sanitary management system and the conversion of dietician' perception on sanitary managements in food service institutions were needed.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.640-652
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• 1994

This work is undertaken to determine alcohol homologues so-called fusel oil that may be present in the Korean folk sojues (distilled liquor) made from grains and to describe sample preparation and analytical method by GC-FID-MS. Solid phase extraction method for sample preparation by using porous styrene divinyl benzene polymer (Porapak Q) was compared with steam distillation and solvent extraction method. Retention behaviors of homologous series of alcohols were also studied. Log values of retention time, molecular weight, boiling point, and capacity factor of alcohols showed linear correlations to the carbon number of an alcohol, to the oven temperature, and to the dielectric constant. Components such as methyl alcohol, n-propyl alcohol, isobutyl alcohol, isopentyl alcohol, and phenethyl alcohol have been identified. The more amount of isopentyl alcohol than other alcohols are contained in the Korean folk sojues, while that of n-propyl alcohol are contained in Chinese kaoliangchiew. Degree of similarity or dissimilarity and classification of the individual samples were discussed using multivariate statistical analysis(principal components analysis) based on GC data.