• 한국식품과학회지
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• 제1권1호
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• pp.78-84
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• 1969

An attempt has been made to investigate the possible occurrence of aflatoxins, a group of micotoxin which are toxic metabolites produced by Aspergillus flavus, and aflatoxin like substances in fungal fermented soybean products such as meju and soybean paste. Chloroform extracts from 15 samples which has been defated with petroleum ether are subjected to separations with thin-layer chromatography on silica gel washed with methanol prior to film coating, improves the chromatographic separation and ultraviolet absorption spectral identification. In addition to fluorescencing spot having an Rf value which is same as aflatoxin $B_1$, many of the fluorescencing spots have been occurred in every sample examined. Each fluorescencing spot is scratched and the ethanol extracts are subjected to further separation with thin-layer chromatography. Each fluorescence substance is eluted with ultra violet transparent absolute ethanol and the ultraviolet absorption spectra are checked. None of the absorption curve of eluates shsow accordance with the curve of aflatoxin. 2, 4-Dinitrophenyl hydrazine reagent, Tollen's reagent and ninhydrin reagent are applied on the chromatogram- The data show that aflatoxin is not present in any of the fungal preparations examined.

• 한국식품과학회지
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• 제5권3호
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• pp.157-162
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• 1973

무균(無菌) 상태하에서 습윤한 여지위에 숙성(熟成)시킨 감자 괴경 박편(塊莖 薄片) $(1mm{\times}1.5cm)$을 재료로 방사선(放射線)의 작용기작(作用幾作)연구를 행하였다. Invertase, 핵산 및 호흡작용의 time courses를 결정하고 이들 세작용의 방사선(放射線)에 대한 민감도를 측정하였다. 세 작용 중 어느 것도 세포분열을 억제하는 선량에서 심하게 억제되지 않았다. $^3H-thymidine$의 incorporation 결과는 방사선(放射線)의 작용부위가 mitosis나 $G_2$ period에 존재할지도 모른다는 것을 암시한다.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.59-65
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• 2014

We measured the reductions in size and solubility of mackerel muscle that was freeze-dried, deoiled by supercritical carbon dioxide (SC-$CO_2$), or roasted. The percent size reduction and solubility were high in SC-$CO_2$-treated muscle compared with freeze-dried and roasted muscle. We used oil-free residues to test for heavy metals and determine microbial safety. The SC-$CO_2$, hexane, and ethanol were used to separate oil from muscle. The concentrations of cadmium (Cd) in all treated muscles were less than the values reported in the literature, as were the concentrations of lead in SC-$CO_2$- and hexane- treated muscle. In contrast, concentrations of arsenic and mercury in muscles were greater than the reported values regardless of treatment. Zinc and iron, which are beneficial for health, were found in high levels after all treatments of muscle tissue. After 6 months of storage at different temperatures, SC-$CO_2$-and ethanol-treated muscle showed few bacterial colonies, and none were found after 4 months of storage at $-20^{\circ}C$. These results will be useful to food-processing industries for maintaining high-quality, safe mackerel muscle.

• 대한기계학회논문집A
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• 제36권1호
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• pp.109-116
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• 2012

현재 천공장비 및 천공방법에 대한 많은 연구가 진행되고 있지만 DTH hammer의 타격성능을 규명하고 최적화에 대한 연구는 전무하다. 또한 DTH drilling의 시험 장비를 구축하기 위해서는 막대한 비용과 많은 시간이 요구되기 때문에 성능규명에 있어 시험적으로 접근하기가 매우 곤란한 실정이다. 따라서 본 논문에서는 DTH hammer의 구동원리를 파악 후 공압 해석을 이용하여 구동 특성 및 성능을 규명하였다. 또한 실험계획법을 이용하여 DTH hammer의 성능에 영향력이 있는 설계인자를 도출하고 이를 다구찌 기법에 적용해 DTH hammer의 타격성능인 타격수와 타격에너지의 최적화에 대한 연구를 수행하였다.

• 한국재료학회지
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• 제29권3호
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• pp.189-195
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• 2019

The effect of C, Mn, and Al additions on the tensile and Charpy impact properties of austenitic high-manganese steels for cryogenic applications is investigated in terms of the deformation mechanism dependent on stacking fault energy and austenite stability. The addition of the alloying elements usually increases the stacking fault energy, which is calculated using a modified thermodynamic model. Although the yield strength of austenitic high-manganese steels is increased by the addition of the alloying elements, the tensile strength is significantly affected by the deformation mechanism associated with stacking fault energy because of grain size refinement caused by deformation twinning and mobile dislocations generated during deformation-induced martensite transformation. None of the austenitic high-manganese steels exhibit clear ductile-brittle transition behavior, but their absorbed energy gradually decreases with lowering test temperature, regardless of the alloying elements. However, the combined addition of Mn and Al to the austenitic high-manganese steels suppresses the decrease in absorbed energy with a decreasing temperature by enhancing austenite stability.

• International Journal of Advanced Culture Technology
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• 제8권4호
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• pp.58-63
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• 2020

In literature it is not only the meaning of words which matters, but also their texture matters i.e. their rhythm, colour and style are relevant and none of these natures can be reduced to an item of information. The texture is also important in film languages, especially the rhythm. In order to make the storytelling rhythm visible, a new concept of 'the Rhythm Chart Analysis Method (RCAM)' has been devised in this research and used for analysis. By analyzing original films and remakes in Korean and Chinese, one can find out that different countries have different storytelling rhythms i.e. the same story can be told in different rhythms. The central idea in Korean films is portrayed at the end, which is a typical characteristic of Korean films. And as the defining moment does not occur suddenly the audience can naturally get immersed into the story. But Chinese films communicate with the audience in a more direct way. It directly mentions characteristics of each actor in such a way that it is telling rather than showing. The information of the movie is given to the audience in the initial stages of the movie. Rhythm is as important as story and information. And through this we can find out the cultural differences from the different storytelling rhythms.

• Journal of Animal Science and Technology
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• 제64권5호
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• pp.863-870
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• 2022

This study was conducted to investigate the effect of dietary supplementation of octacosanol (OCT) extracted from triticale sprout on laying performance, egg quality, and blood parameters of laying hens. A total of 192, Hyline brown laying hens aged 43 weeks were divided into 4 dietary groups of 48 birds each and they were randomly subjected to one of the experimental diets containing OCT at the levels of none, 10, 20, and 30 mg/kg of diet. All birds were fed with isoenergetic and isonitrogenous mash diets for 6 weeks. The result showed that hens supplemented with 20 and 30 mg/kg OCT in diet significantly increased (p < 0.05) egg production than those fed with the basal diet. OCT concentration in the egg yolk of hens fed with 20 and 30 mg/kg OCT was significantly higher than in those fed the control diet. Hens fed 20 and 30 mg/kg OCT exhibited greater high-density lipoprotein (HDL) cholesterol and interleukin (IL) concentrations and reduced serum concentrations of cholesterol and triglyceride compared to those fed with 0 and 10 mg/kg OCT. This study indicates that supplementing the diet of laying hens with 20 and 30 mg/kg of OCT can improve the performance, egg quality, and health status of laying hens.

• 한국광물학회지
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• 제10권1호
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• pp.18-32
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• 1997

Analysis of geological data, relating to occurrence and formation of diamonds as well as host rocks, inclined author to have different outlook on the diamond genesis and to establish a proposition on their formation at pneumatolytic-hydrothermal conditions near superficial Earth zones. Based on that theoretical foundations and experimental works, the first low-pressure and low-temperature hydrothermal diamond synthesis from water solution in pressure autoclave was executed. As a result, the natural diamond seed crystal grew bigger ad coupling of the synthetic diamond single-crystalline grains were obtained. SEM documentation proofs that parallely paragenetic crystallization of quartz and diamond, and nucleation of new octahedral diamond crystals brush take place on the seed crystal surface. Forecast of none times growth of diamond industrial application at 2000 and seventeen times at 2010 with reference to 1995, needs technology of large and pure single-crystals diamond synthesis. Growth of the stable and destressed diamond single-crystals in the pseudo-metastable diamond plot, may be realized with processes going through the long time and with participation of free radicals catalysts admixtures only. Sol-gel colloidal processes are an example of environment which form stable crystals in thermodynamically unstable conditions through a long time. Paper critically discusses a whole way of studies on the diamond synthesis, from high-pressure and high-temperature processes through chemical vapour deposition up to hydrothermal experiments.

• Korean Journal of Radiology
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• 제21권7호
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• pp.919-924
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• 2020

Objective: The current study reported a case series to illustrate the early computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) in pediatric patients. Materials and Methods: All pediatric patients who were diagnosed with COVID-19 and who underwent CT scan in Zhongnan Hospital of Wuhan University from January 20, 2020 to February 28, 2020 were included in the current study. Data on clinical and CT features were collected and analyzed. Results: Four children were included in the current study. All of them were asymptomatic throughout the disease course (ranging from 7 days to 15 days), and none of them showed abnormalities in blood cell counts. Familial cluster was the main transmission pattern. Thin-section CT revealed abnormalities in three patients, and one patient did not present with any abnormal CT findings. Unilateral lung involvement was observed in two patients, and one patient showed bilateral lung involvement. In total, five small lesions were identified, including ground-glass opacity (n = 4) and consolidation (n = 1). All lesions had ill-defined margins with peripheral distribution and predilection of lower lobe. Conclusion: Small patches of ground-glass opacity with subpleural distribution and unilateral lung involvement were common findings on CT scans of pediatric patients in the early stage of the disease.

• 한국식품과학회지
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• 제4권2호
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• pp.134-139
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• 1972

한국산(韓國産) 주요(主要) 과실류(果實類)로 미숙(未熟) 및 완숙(完熟)의 매실, 복숭아, 포도, 사과 및 배의 주요(主要) 품종별(主要品種別) 비휘발성(非揮發性) 유기산(有機酸) 및 당(糖)의 계절적(季節的) 비휘발성(非揮發性) 유기산(有機酸) 및 당(糖)의 함량변화(含量變化)를 구명(究明)하기 위하여 비휘발성(非揮發性) 유기산(有機酸)은 gas chromatography법(法)으로 당(糖)은 thin layer chromatography법(法)으로 분석(分析)하여 다음과 같은 결과(結果)를 얻었기에 보고(報告)하는 바이다. 1) 이들 과실중(果實中)의 비휘발성(非揮發性) 유기산(有機酸)은 oxalic, fumaric, succinic, maleic, tartaric 및 citric acids 이고 함량(含量)은 $0{\sim}3430mg/100g$이었다. 2) 위과실(果實)에 함유(含有)된 유기산(有機酸) 중(中) malic acid가 $18{\sim}3430mg/100g$로 가장 많다. 매실(梅實)에 함유(含有)된 10.8mg/100g를 제외(除外)하고는 oxalic acid가 가장 적었다. 3) 일반적(一般的)으로 모든 비휘발성(非揮發性) 유기산(有機酸) 함량(含量)은 성숙(成熟)과 더불어 그 양(量)이 감소(減少)되었다. 단 열외(列外)로서 사과 및 배의 각(各 ) 일품종(一品種)에서는 증가(增加)하였다. 4) Glucose 및 fructose는 모든 과실중(果實中)에 다량(多量) 함유(含有)되어 있으며 maltose와 sucrose는 소량(小量)씩 함유(含有)되었다.