• 한국산업보건학회지
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• 제18권3호
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• pp.224-238
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• 2008

The aim of this study is to confirm the physicochemical property and hazard of thinner (012), which is a diluent of enamel paint used for floor coating for waterproofing and oil painting for the outer wall. The literatures of physicochemical property and hazard of thinner were surveyed and its physicochemical property were evaluated. And then, the inhalation toxicity of thinner affecting the central nervous system and reproductive organs in rats were examined by subchronic (6 h./day. 5 days/ week for 13 weeks) inhalation test. 1) According to the 13-week subchronic inhalation test, there were no significant changes in clinical test and body weight. However, a significant evidence of toxicity was observed in the hematological test and organ weight such as heart, kidney, liver and brain (p<0.01) in the 200 ppm and 1,000 ppm exposure groups in a dose response manner. In the histopathology analysis, there were no significant evidence of toxicity. Therefore, thinner was not classified as an organ targeted toxic agent. In case of Harmfulness, it could be classified as a chronic toxic agent 3($500 ppm/4hr, rat). 2) The reproductive toxicity such as extension of the period of estrous cycle, reduction of serum estradiol concentration and increase of frequency of the abnormal sperm was observed in the 1,000 ppm exposed animals. 3) The result of the physicochemical property of the test material showed that the specific gravity was 0.793, boiling point $155.8^{\circ}C$, steam pressure 2.1 kPa, ignition point $34.5^{\circ}C$, and spontaneous ignition point $280^{\circ}C$. The endothermic and exothermic values were 371.4 J/g and 159.1 J/g. respectively. The explosion limit was 214 mg/l. These data showed that thinner could be classified as an explosion agent level 1.2 and ignitive liquid agent 3 ($23-60^{\circ}C$) according to the notification No. 2008-1 of the Labor Ministry, "Classifying Standard of Chemical Materials."

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.269-269
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• 2017

Germination is one of the techniques used to enhance the texture properties and nutritional value of the brown rice (BR). Therefore, germinated BR (GBR) has received significant attention during the last decade. Physicochemical and cooking properties of brown rice were examined before and after germination. Germination raised the cooking properties, such as water absorption, expanded volume and soluble solid of cooked BR (brown rice). The texture, measured using tensipresser, was significantly improved by germination. The hardness of cooked BR was decreased by germination, but the GBR was sticker. In RVA, all viscosity value (peak viscosity, break down, set back, and final viscosity) of germinated rice flour was also reduced while gelatinization temperature did not change. Amylose content and amylopectin chain length distribution of BR starch were slightly changed by germination. Overall results revealed that germination was an effective tool to improve texture and cooking properties of BR.

• 한국토양비료학회지
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• 제44권4호
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• pp.545-550
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• 2011

Urea intercalated into montmorillonite (MT) exhibits remarkably enhanced N use efficiency, maintaining its fast effectiveness. This study dealt with the release property of urea from metal-urea-clay hybrid with MT (MUCH) under continuous-flow conditions and the cumulative impacts of its successive application on physicochemical properties of soils. Releases of urea were completed within 4 hrs under continuous-flow condition regardless of the types and the leaching solutions. However, urea release property was significantly affected by both the form of fertilizer and the presence of electrolytes in solution. The fast release property of urea from MUCH in continuous-flow condition was not significantly affected by soil properties such as soil pH and soil texture. In addition, its successive application did not lead to any noticeable change in soil physicochemical properties, water stable aggregate rate, water holding capacity and cation exchange capacity in both sandy loam and clay loam soils. Therefore, this study strongly supported that urea intercalated into MT could be applied as fast-effective N fertilizer, in particular for additional N supply.

• The Plant Pathology Journal
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• 제16권5호
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• pp.283-285
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• 2000

Two field tests were conducted in 1995 to examine the effects of composts and soil amendments on physicochemical properties of soil in relation to Phytophthora root and crown rot of bell pepper. Chitosan, crab shell waste, humate, sewage sludge-yard trimmings, and wood chips were applied to test plots, some of which affected the levels of P, K, Mg, pH, and H. Physicochemical properties were not related with disease incidence, but percent organic matter, estimated nitrogen release, K, and Mg were correlated with total microbial activity. The elements K and Mg were especially responsible for the increased soil microbial activity that could affect development of root and crown rot of pepper.

• 동아시아식생활학회지
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• 제7권4호
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• pp.519-526
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• 1997

Propylene oxide와 반응시켜 치환도가 0-0.2645되는 하이드록시프로필화 감자 전분을 제조하여 이화학적 성질들을 측정하였다. 전분의 하이드록시프로필기 함량은 propylene oxide의 농도에 비례하였다. 하이드록시프로필화 감자 전분의 물결합력은 치환도가 증가할수록 증가하였고 pH는 치환도가 증가할수록 감소하였다. 청가와 요오드 흡착 강도는 치환도가 증가할수록 감소하였다. 시차주사열량계에 의한 호화양상에서는 하이드록시프로필화에 의해 전분의 호화온도가 낮아지는 것으로 나타났다. 하이드록시프로필화에 의해 전분의 상대 결정 화도는 낮아졌고, 전분 입자가 파괴되었음이 X-선 회절도와 주사전자현미경으로 각각 관찰되었다. 이것은 고농도의 하이드록시프로필화가 전분의 무정형 부분뿐만 아니라 결정성 영역에까지 영향을 주었음을 의미하였다.

• Food Science and Biotechnology
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• 제17권5호
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• pp.1010-1015
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• 2008

The effects of heat treatment on the physicochemical properties and mineral composition of sun-dried salt were investigated. The salts parched at high temperature were appeared the higher alkalinity and the lower oxidation-reduction potential (ORP) than the samples without heat treatment. The commercial salts (bamboo salt and yellow loess salt) and the sun-dried salt parched at high temperature had relatively higher sodium ion content (418-450 ppm) compared to that (418.0 ppm) of refined salt. The increase of calcium ion occurred in the salts parched at high temperature compared to the sun-dried salt without heat treatment, but the magnesium ion was vice versa. The commercial salt, yellow loess salt had highest turbidity (0.973) whereas sun-dried salt showed lowest level (0.097) among the tested samples. Turbidity of heat treatment samples decreased as solubility increased. The maximum concentration of dialyzed salt was reached after 4 hr regardless of various processed salts, but those had no difference significantly among the tested samples. The X-ray diffraction patterns of the parched sun-dried salts showed different peak intensity with common salts, and they were similar to the patterns of oxide salts, especially MgO. The maximum value (2.56%) of MgO appeared in the sun-dried salt parched at $1,400^{\circ}C$.

• 한국식품영양학회지
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• 제29권5호
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• pp.692-697
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• 2016

This study was aimed to develop a gruel using rice extrudates and to evaluate physicochemical properties of Tarakjuk (milk porridge; MP) prepared with milk (M) and rice powder (RP, control), rice extrudate (RE), or enzyme treated rice extrudates (ETR). Pasting property of ETR was significantly different from those of RP or RE with significantly low peak viscosity, breakdown and setback values in the ETR sample. Viscosity of MP prepared with ETR was also significantly low, as compared to that of control (> 900 cP). The total solids and spreadability of MP with ETR was higher than those with RP or RE. Hunter color values varied significantly depending on enzyme treatment levels in ETR samples with enzyme dose-dependent increase in b-value. Average starch digestibility of ETR sample was higher by 10.2% than that of control sample. DPPH radical scavenging activities of ETR samples were greater than those of RE or RP. These results indicated that ETR could be beneficial for preparing easy-drink and diet food with higher starch digestibility and fluidity, especially for gastric tube-fed patients.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1145-1149
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• 2009

Physicochemical properties of native and acid-modified Job's tears (Coix lachryma-jobi L.) starches were investigated. Starch extracted from Job's tears was treated with 2.2 N hydrochloric acid for different length of time (3, 6, 12, and 18 hr). The hydrolysis pattern of starches with the acid proceeded rapidly up to 12 hr and then the approached constant values. The swelling power of acid-modified starches measured at all temperatures was lower than that of its native counterparts and the water solubility index increased as temperature and hydrolysis time increased. Rapid visco analyzer viscograms of acid-modified starches demonstrated a very low viscosity as compared with that of native starch. However, Xray diffraction did not show any significant alteration in the crystallinity after acid-modification.

• 한국자원식물학회지
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• 제29권3호
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• pp.313-321
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• 2016

Persimmon has long been established as one of the major fruits in Korea. The southern parts of Korea were traditionally the pocket areas for good persimmon production; however, rising temperatures have gradually rendered the southern regions unsuitable for successful harvest. Ecology of fruit growing areas affects the productivity of various types of crops, including fruit trees such as persimmon. The quality characteristics of the fruit of persimmon cv. Dongchul grown in Gangwondo, which lies in the northern part of South Korea, were investigated. Different physicochemical, nutritional, and antioxidant properties of fruit were evaluated to assess the locational effect on the quality of persimmon fruits grown in Gangwondo. The results of this study showed that persimmon cv. Dongchul grown in Gangwondo maintains many of the physicochemical (4.33% crude protein and 4.32% crude fiber), nutritional (total mineral content: 461.51 and vitamin C content: 15.28 ㎎/100 g), and antioxidant properties (polyphenol content: 633.1 ㎎ gallic acid equivalent/100 g) those are found in other three commercial cultivars ‘Daebong’, ‘Kyengsan Bansi’, and ‘Sangju Doongsi’ grown in Korea. Overall results of this study imply that ‘Dongchul’ cultivar of persimmon could commercially be grown in Kangwondo, Korea.

• 산업식품공학
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• 제15권2호
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• pp.169-174
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• 2011

This study was performed to analyze the effects of ultra fine pulverization (UFP) on the physicochemical properties of sweet potato starch (SPS). The average diameter and specific surface area of the SPS was decreased from 22.94 to 10.25 $\mu$m and from 0.879 to 1.909 $m^2$ /g throughout UFP, respectively, and the damaged starch content was increased from 13.7 to 99.2%. The pulverized sweet potato starch (PSPS) had higher swelling power, solubility, and transmittance values than the SPS. X-ray diffractograms revealed that the SPS had a C-type pattern, which disappeared in PSPS. The rapid visco analysis (RVA) characteristics, peak viscosity, break down, and set back of SPS ceased to exist in PSPS. According to differential scanning calorimetry (DSC) curves, the peak temperature ($T_p$) and gelatinization enthalpy ($\Delta$E) of SPS were $71.95^{\circ}C$ and 10.40 J/g, respectively, while these remained undetected in PSPS. The enzymatic digestibilities of SPS and PSPS were 61.7 and 84.7%, respectively.