• Journal of the Korean Wood Science and Technology
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• 제42권5호
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• pp.605-614
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• 2014

This study investigated microstructural changes of cured urea-formaldehyde (UF) resins mixed with aqueous rubber latex emulsion after intentional acid etching. Transmission electron microscopy (TEM) was used in order to better understand a hydrolytic degradation process of cured UF resins responsible for the formaldehyde emission from wood-based composite panels. A liquid UF resin with a formaldehyde to urea (F/U) molar ratio 1.0 was mixed with a rubber latex emulsion at three different mixing mass ratios (UF resin to latex = 30:70, 50:50, and 70:30). The rate of curing of the liquid modified UF resins decreased with an increase of the rubber latex proportion as determined by differential scanning calorimetry (DSC) measurement. Ultrathin sections of modified and cured UF resin films were exposed to hydrochloric acid etching in order to mimic a certain hydrolytic degradation. TEM observation showed spherical particles and various cavities in the cured UF resins after the acid etching, indicating that the acid etching had hydrolytically degraded some part of the cured UF resin by acid hydrolysis, also showing spherical particles of cured UF resin dispersed in the latex matrix. These results suggested that spherical structures of cured UF resin might play an important role in hindering the hydrolysis degradation of cured UF resin.

• 한국결정성장학회지
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• 제19권5호
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• pp.215-222
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• 2009

Many concepts of external magnetic field applications in crystal growth processes have been developed to control melt convection, impurity content and growing interface shape. Especially, travelling magnetic fields (TMF) are of certain advantages. However, strong shielding effects appear when the TMF coils are placed outside the growth vessel. To achieve a solution of industrial relevance within the framework of the $KRISTMAG^{(R)}$ project inner heater-magnet modules(HMM) for simultaneous generation of temperature and magnetic field have been developed. At the same time, as the temperature is controlled as usual, e.g. by DC, the characteristics of the magnetic field can be adjusted via frequency, phase shift of the alternating current (AC) and by changing the amplitude via the AC/DC ratio. Global modelling and dummy measurements were used to optimize and validate the HMM configuration and process parameters. GaAs and Ge single crystals with improved parameters were grown in HMM-equipped industrial liquid encapsulated Czochralski (LEC) puller and commercial vertical gradient freeze (VGF) furnace, respectively. The vapour pressure controlled Czochralski (VCz) variant without boric oxide encapsulation was used to study the movement of floating particles by the TMF-driven vortices.

• International Journal of Costume and Fashion
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• 제8권1호
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• pp.65-74
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• 2008

Religion is deeply connected with human culture and life, and affects all areas of religious people's lives. The aim of this study was to find out how fashion-conservativeness of religious people and non-religious people differ in Korea. Ten religious people and ten atheists all in their twenties were interviewed to find out the differences between religious people and non-religious people related to their viewpoints on clothes. The twenties age group was selected because people in their twenties are sensitive to fashions and styles, and a fair proportion of males and females were selected. The subjects were asked demographic questions, questions about their religion and faith, whether or not they thought they were conservative or affected by religion, and finally, what they thought of photographs of certain styles. 12 photographs from the 2006-7 F/W collections of London, Paris, New York and Milan were presented to the subjects. The photographs were from the Vogue U.K. website and divided into 6 major styles based on verbal evidence used to describe the collections in catwalk reports: "Sexy," "attitude/confidence," "luxury," "sophisticated/chic," "feminine," and "rock." In conclusion, religious people were found to be more conservative than non-religious people in their twenties because they prefer more conservative and covered up styles, have more negative views of bold and skin-showing trends, and regard some styles to be too sexy when non-religious people do not.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.413-419
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• 1994

Mold growth decreased nutritive value of wheat straw (WS). Mold increased DM (94 vs 98%) and ADF (51 vs 56%) contents and had no effect on natural detergent fiber (NDF). Crude protein and N values were decreased in moldy wheat straw, Mold increased insoluble N content of wheat straw (WS) from 21 to 27%. Ammoniation increased the CP of nonmoldy straw from 3.8 to 8.3% and moldy straw from (3.3 to 6.2%). Aspergillus and zygomycetes fungal species were most prevalent and total numbers were higher on moldy straw. Ammoniation decreased total numbers of fungal spores on nonmoldy and moldy WS. Ammoniation of moldy WS increased (p < 0.10) feed in take (1.8%) as compared with nonmoldy, ammoniated, nonmoldy and moldy WS. Steers fed moldy WS had lowest (p < 0.10) feed intake (1.3% of BW daily) compared with other diet. There was little difference (p < 0.10) in intake of nonammoniated vs. ammoniated WS. Steers fed moldy straw lost 6 kg BW. Ammoniated, nonmoldy straw elevated Blood Urea Nitrogen (BUN) (10.5 mg/dl). Alkaline Phosphatase (ALK) was greater in steers fed moldy VS nonmoldy straw (148 VS 95 U/liter. p < 0.10).

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.255-260
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• 1994

Calving records of 107 heifers from two breed groups were used to identify the major factors contributing to calving difficulty (dystocia) and compare the influence of pelvic diameters, weight and height of heifers measured after breeding and before calving on dystocia. The horizontal and vertical pelvic diameters, hip height and weight of heifers were measured two months after breeding and again two months before calving. Snell transformed calving difficulty scores (0 = normal to 100 = surgical intervention) were used in analyzing the data by analysis of covariance. Body condition score of the heifer, sire birth weight of the calf, birth weight of the calf, and ratio of calf birth weight to pelvic area all had significant effects on dystocia. Calf birth weight, ratio of calf birth weight to pelvic area, and heifer's condition score were especially important. However, sex of calf did not have a significant influence on dystocia. Generally, the variables measured before calving accounted for a higher proportion of variation in dystocia than those measured after breeding. Thus, based on the relative importance of the major factors affecting dystocia, it is suggested that selection of bulls with low birth weight for breeding on normal size heifers with optimum body condition score, and well developed pelvic opening, would be effective in reducing the incidence and severity of dystocia in beef heifers.

• Asian-Australasian Journal of Animal Sciences
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• 제9권2호
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• pp.123-126
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• 1996

Sixteen Harnai males were used to evaluate the influence of varying levels of fourwing saltbush hay on feed and water intakes as well as the blood serum mineral status in a completely randomized design. The animals were grouped randomly into four, with four animals in each. The four groups were randomly allotted low, medium, high and very high levels of saltbush hay supplementation in addition to wheat straw. The animals were given fresh water at free of choice. Weekly body weight was recorded for each individual animal. Blood serum was collected for mineral contents. The experiment lasted for eight weeks. The inclusion of saltbush leaves in the diet showed a non-significant effect on the total dry matter intake. There has been a significant increase in the water intake when very high levels of saltbush were included in the ration. Lower levels showed no effect on the water intake. The animals maintained their body weight from week 1 to week 8. No treatment by weeks interactions on the potassium and sodium levels were detected. However higher levels of saltbush increased significantly the potassium and sodium contents in the serum. Calcium contents were significantly(p<0.01) lowered with the inclusion of saltbush leaves in the diet. Whereas Phosphorous contents showed an increasing(p<0.05) trend with the higher levels of saltbush. No clinical or sub-clinical toxicological symptoms were observed in the sheep with the higher mineral contents.

• Mycobiology
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• 제33권4호
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• pp.206-209
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• 2005

Narceine methyl ester and narceine are potent alkaloids which were isolated from Corydalis longipes were found effective in vitro at very low concentration, i.e., $100{\sim}500\;ppm$ against spore germination of some test plant pathogenic fungi (Alternaria solani, A. tagetica, Cercospora abelmoschi, Curvularia maculans, Erysiphe cichoracearum, E. pisi, Fusarium udum, Helminthosporium oryzae, H. penniseti, Ustilago cynodontis). Among the test, phytopathogens the spores of F. udum, C. maculans and H. penniseti were highly sensitive at 200 ppm. However, spores of E. pisi, A. solani and A. tagetica were less sensitive at low concentration followed by other test fungi. Most of the fungi showed zero or nearly zero percent spore germination at 400 and 500 ppm.

• 전력전자학회논문지
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• 제17권2호
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• pp.182-189
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• 2012

In this paper, the input current and output voltage ripple of the soft switching interleaved boost converter was analyzed. Ripples of input current and output voltage with an interleaved method is analysed and as a result, the facts that it has lower ripple current than conventional interleaved method is verified. it means that a capacity of a main inductor can be reduced. Besides, a low capacitance of capacitor which means high lifetime and confidence can be used because of reducing ripples of output voltage. In order to verify the validity of the proposed converter used 10uF film capacitor, experiment was performed, and the efficiency of the proposed converter was measured with variable load and duty conditions.

• 한국식품영양과학회지
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• 제32권7호
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• pp.960-964
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• 2003

오디 색소인 안토시아닌 색소의 안정성에 대한 pH, 당, 유기산, 금속이온의 영향을 조사하였다. 오디 색소는 pH가 낮을수록 색소의 강도와 안정성이 증가하였다. Glucose, fructose, sucrose 및 maltose 첨가시 sucrose 첨가에 의해 색소 강도가 가장 많이 감소하였으며, glucose와 maltose는 다른 당류에 비해 비교적 적은 색소 강도의 변화를 보였다. Citric acid, maleic acid, tataric acid 및 acetic acid 첨가시 첨가농도가 증가할수록 색소 강도가 증가하였으며, 색소의 안정성에 대한 유기산의 첨가 효과는 maleic acid, acetic acid, citric acid, tartaric acid 순으로 나타났으며, 구리와 철 이온 첨가는 다른 금속이온에 비해 색의 강도가 감소하였다.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.286-290
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• 2006

A genomic library of Streptococcus vestibularis ATCC49124 was constructed in an E. coli plasmid vector, and the urease-positive transformants harboring the urease gene cluster were isolated on Christensen-urea agar plates. The minimal DNA region required for urease activity was located in a 5.6 kb DNA fragment, and a DNA sequence analysis revealed the presence of a partial ureI gene and seven complete open reading frames, corresponding to ureA, B, C, E, F, G, and D, respectively. The nucleotide sequence over the entire ure gene cluster and 3'-end flanking region of S. vestibularis was up to 95% identical to that of S. salivarius, another closely related oral bacterium, and S. thermophilus, isolated from dairy products. The predicted amino acid sequences for the structural peptides were 98-100% identical to the corresponding peptides in S. salivarius and S. thermophilus, respectively, whereas those for the accessory proteins were 96-100% identical. The recombinant E. coli strain containing the S. vestibularis ure gene cluster expressed a high level of the functional urease holoenzyme when grown in a medium supplemented with 1 mM nickel chloride. The enzyme was purified over 49-fold by using DEAE-Sepharose FF, Superdex HR 200, and Mono-Q HR 5/5 column chromatography. The specific activity of the purified enzyme was 2,019 U/mg, and the Michaelis constant ($K_{m}$) of the enzyme was estimated to be 1.4 mM urea. A Superose 6HR gel filtration chromatography study demonstrated that the native molecular weight was about 196 kDa.