• 환경위생공학
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• 제2권3호
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• pp.13-22
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• 1987

For the amino-N -ratio and N- solubity, irradiated samples were higher than non - irradiated them, that is, 15KGy(l9, 72), 7KGy(l9, 55) of amino-N-ratio were more those of 5KGy(17. 91) and l0KGy(l8, 06). during the fermentation of samples. For the Solubility of nitrogen, irradiated samples were decreased sequencely, such as 10KGy, 7KGy, 15KGy and 5KGy. For the amounts of amino acid, Content of the glutamic acid was the highest in the all samples and the main free amino acids in the Steamed Soybeans Were glutamic acid, proline, arginine, and alanine etc. However the amount of amino acid in the irradiated Sample was notably increased in Comparison with the nonirradiated $(10.8017\%)$ and 7KGy amino acid $(15.4166\%)$ was highest.

• 한국식품조리과학회지
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• 제9권1호
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• pp.30-32
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• 1993

'89, '90, '91년산 장엽대두를 냉장보관하면서 저장에 따른 그 품질과 이화학적 특성의 변화를 살펴보았다. 총당함량과 Phytate 함량은 수확시기와 저장기간에 따른 차이를 나타내지 않았으며 질소용해도 계수(NSI)는 98.42%에서 89.92%로 저장기간이 길수록 감소하였다. 대부분의 amylogram viscosity 특성은 '89년과 '90년산은 거의 유사하였으나 '91년산은 더 높은 최고점도와 break-down을 나타내었다. 콩나물의 수율은 '89년산이 334.8%로 가장 낮았고 발아율도 57.4%로 가장 낮은 값을 나타내었다.

• 동아시아식생활학회지
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• 제10권5호
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• pp.394-403
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• 2000

The functional properties of sesame protein concentrate(SPC) using different size of ultrafiltration(UF) membranes were examined and compared with those of conventional acid-precipitated sesame protein concentrate. The protein contents of SPC by UF with molecular size of 10K, 30K and look dalton membranes were 84.2%, 82.7%, and 76.4%, respectively, and that of acid-precipitated SPC was 88.7%. The nitrogen solubility of SPC by UF was higher than that of conventional SPC at various pH levels. Especially, it showed three-fold increase at near isoelectric point. However, water absorption capacity and fat absorption capacity of SPC by UF were decreased. For emulsion and foam properties, there were no significant differences between SPC by acid precipitation and SPC by UF method. At various pH levels, SPC by membrane with pore size of 30K dalton showed the highest emulsion properties. The SPC by UF had slightly higher viscosity than defatted sesame flour and SPC by acid precipitation.

• Elastomers and Composites
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• 제54권4호
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• pp.321-329
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• 2019

A series of poly(hyroxyamide)s (PHAs) was prepared by direct polycondensation reaction of 4,4'-(2,3-pyridinedioxy)dibenzoic acid and/or isophthalic acid with 3,3'-dihydroxybenzidine. The yield percentages of the products were high, and the inherent viscosities of the polymer in DMAc solution at 35℃ were 0.31-0.59 dL/g. All PHA polymers were found to be soluble in polar aprotic solvents such as DMAc, DMSO, NMP, and DMF. On the other hand, LiCl was required to dissolve IPHA-1 in aprotic solvents. Poly(benzoxazole)s (PBOs) were partially soluble in conc-H₂SO₄; IPBO-4, -5, and -6 were partially soluble in NMP only when LiCl was added to the solution, and the solution was heated. The PBO polymers showed a maximum weight loss in the temperature range of 654-680℃, and the char yields at 900℃ under nitrogen atmosphere exceeded 63%.

• Elastomers and Composites
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• 제55권3호
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• pp.205-214
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• 2020

A series of wholly aromatic polyhyroxyamide (PHA) copolymers were prepared by direct polycondensation reaction of isophthalic acid and diacids containing bulky units with 3,3'-dihydroxybenzidine. The inherent viscosities of the PHAs measured at 35℃ in DMAc solution were in the range of 0.31-0.56 dL/g. The solubility study revealed that the PHAs were readily soluble in aprotic solvents such as, dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), and N-methyl-2-pyrrolidone (NMP) at room temperature and in less polar solvent such as pyridine. However, the polybenzoxazole (PBO) copoymers were quite insoluble in all organic solvents except partially soluble in concentrated sulfuric acid and partially soluble in NMP containing LiCl. The PBO copolymers showed maximum weight loss temperature in the range of 593-632℃ and high char yields in the range of 65.0-71.2% at 900℃ in a nitrogen atmosphere.

• Preventive Nutrition and Food Science
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• 제4권3호
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• pp.159-162
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• 1999

The purpose of this research was to study the effects of initial moisture levels and extrusion temperatures on dietary fiber, nitrogen solubility index, available lysine, and the in vitro protein digestibility of extruded oat productes. The dehulled grains were ground in a Brabender quadrumat Senior mill and the coarse fraction, with higher crude protein, lipids and dietary fiber were conditioned on various mositre levels (15.5~25.5%) and extruded in a Brabender single-screw laboratory extruder. The extrudates showed a higher amount of soluble dietary fiber (8.14%) than in the raw material . However, the extrusion process affected the nutritional value of the protein due to a decrease in available lysine with increased temperature . The in vitro protein digestibility was unaffected by initial moisture levels and the extrusion temperatures examined.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.398-400
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• 1995

Selective oxidation of cyclohexane in acetone solution has been studied using iron catalysts with hydrogen peroxide in-situ produced by palladium catalyst. Iron tetraphenylporphyrin chloride shows the highest activity among the tested chlorides and porphyrin complexes of some metals of the first transiton series. Iron chloride and iron tetraphenylporphyrin chloride were supported on four kinds of 4-vinylpyridine copolymer with styrene or divinyl-benzene. Nitrogen 1s photoelectron spectra give the evidence that pyridyl nitrogens of the 4-vinyl pyridine copolymer act as ligands to bind iron species. The copolymer with styrene is the most efficient support for the binding because its solubility in catalyst preparation solvent (methylene chloride) gives the pyridyl group advantage to contact with the iron catalysts. However, better catalytic activity per iron atom could be obtained with a rigid crosslinked polymer due to active site isolation.

• Macromolecular Research
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• 제17권11호
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• pp.901-906
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• 2009

Several aromatic optically active polyamides (PA)s were synthesized from 5-(2-phthalimidiylpropanoylamino)isophthalic acid with various aromatic diamines via direct polycondensation with triphenyl phosphite and pyridine in the presence of calcium chloride and N-methyl-2-pyrrolidone under microwave irradiation and conventional heating conditions. Under the optimized conditions, the reaction mixture was irradiated for 2 min. with a 100% irradiation power (900 W). The resulting polymers were obtained in high yield and moderate inherent viscosity ranging from 0.35 to 0.60 dL/g. All synthesized polymers showed excellent solubility in amide-type solvents. Thermogravimetric analysis revealed a 10% weight loss temperature and char yield at $600^{\circ}C$ in a nitrogen atmosphere of > $350^{\circ}C$ and > 58%, respectively, which suggests that the resulting PAs have good thermal stability.

• Corrosion Science and Technology
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• 제12권6호
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• pp.280-287
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• 2013

Flow accelerated corrosion(FAC) of the carbon steel piping in pressurized water reactors(PWRs) has been major issue in nuclear industry. Severe accident at Surry Unit 2 in 1986 initiated the worldwide interest in this area. Major parameters influencing FAC are material composition, microstructure, water chemistry, and hydrodynamics. Qualitative behaviors of FAC have been well understood but quantitative data about FAC have not been published for proprietary reason. In order to minimize the FAC in PWRs, the optimal method is to control water chemistry factors. Chemistry factors influencing FAC such as pH, corrosion potential, and hydrazine contents were reviewed in this paper. FAC rate decreased with pH up to 10 because magnetite solubility decreased with pH. Corrosion potential is generally controlled dissolved oxygen (DO) and hydrazine in secondary water. DO increased corrosion potential. FAC rate decreased with DO by stabilizing magnetite at low DO concentration or by formation of hematite at high DO concentration. Even though hydrazine is generally used to remove DO, hydrazine itself thermally decomposed to ammonia, nitrogen, and hydrogen raising pH. Hydrazine could react with iron and increased FAC rate. Effect of hydrazine on FAC is rather complex and should be careful in FAC analysis. FAC could be managed by adequate combination of pH, corrosion potential, and hydrazine.

• 한국식품영양과학회지
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• 제32권3호
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• pp.400-405
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• 2003

산과 알칼리 수리미 제조공정을 확립하기 위하여 단백질 가용화와 회수를 위한 최적 pH, 이온강도의 영향, 균질화 조건, 마쇄육에 대한 수도수의 비 및 수율을 검토하고, 산 및 알칼리 수리미 공정에 따른 폐수의 오염 저감 효과를 수세수리미와 비교하였다. 어육 단백질을 추출하기 위한 최적 pH는 2.5와 10.5부근이었으며, 가용성 단백질의 침전 회수를 위한 최적 pH는 5.0 부근이었다. 추출 용액의 이온강도 증가는 어육 단백질의 추출량을 현저히 감소시키는 것으로 나타났고, 균질화를 위한 최적 조건은 9500 rpm 이하에서 30초였다. 원심분리 부하량과 파괴강도 및 변형값을 고려한 최적수량은 어육에 대하여 6배량이었다. 산 혹은 알칼리 공정의 수리미 수율은 수세 공정에 비하여 높았으며, 폐수의 오염 부하량은 현저히 낮은 것으로 나타났다.