• Journal of Food Hygiene and Safety
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• v.8 no.2
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• pp.85-90
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• 1993

The aglycones of vicine and convicine have been implicated as the causative factors for favism in fababeans. Thus, the presence of these compounds in fababeans is a potential obstacle to the use of fababeans and fababean preparations in foods. Investigations of vicine stability in fababeans and in pure solutions revealed that vicine is very stable, however, divicine derived from vicine by ${\beta}-gIucosidase$ action or by acid hydrolysis is highly unstable at conditions prevalent in food processing. Therefore, the possibility of incorporating of ${\beta}-gIucosidase$ in food products containing fababean preparations was suggested to overcome potential risks of favism related to the consumption of fababean fortified products.

• Clean Technology
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• v.11 no.2
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• pp.105-116
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• 2005

Carboxymethylcellulose(CMC) which is water soluble at room temperature was manufactured from the cellulose material in this study. Experimental parameters were reaction temperature, time and concentration of NaOH and monochloroacetic acid. CMC was tested for solubility, degree of substitution(D.S.) and tensile strength. The surface structure of CMC fiber was tested using scanning electron microscope(SEM). CMC manufactured from viscose rayon was affected by the chemical concentration rather then the reaction time and temperature. Also, degree of substitution is closely related to the solubility of the CMC.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.413-418
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• 1994

The synthetic steps of sodium(2-(2, 6-dichlorophenyl)amino)phenylacetate were reduced and increased the yield in each steps. The synthetic process was composed to four steps and 2, 6-dichloroaniline and per catalyst in three lots in 80% yield. The steps of acylation and Friedel-Craft reaction were simplified successfully. The final product, diclofenac was obtained in 97% yield by hydrolyzing 1-(2,6-dichlorophenyl)-2-indolinone which was gained in third step with Claisen-solution.

• Korean Journal of Crystallography
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• v.7 no.2
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• pp.133-146
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• 1996

Morphology and infrared absorbing characteristics of Pt-black prepared by electroplating have been investigated with XRD, SEM, and IR spectrophotometer. The Pt later was coated on Au-coated alumina/glass substrates for 1-5 min at pH 1.0-1.5, where a solution of platinum chloride and lead acetate was used as the electrolyte. At the electrical current density of 20-50 mA/㎠, the Pt-black showed a dendritic growth which was characterized by a "tree" shape. Absorptivity of above 90% at IR radiation of 10 m was observed for the Pt absorbing layer with an area density of ≥1.3mg/㎠.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• Journal of Sericultural and Entomological Science
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• v.31 no.1
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• pp.37-44
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• 1989

The parasporal crystals of Bacillus thuringinsis subspecies kurstaki, dendrolimus, finitimus, aizawai and israelensis were compared by polyacrylamide electrophoresis, amino acid composition and immunological analysis. In the subspecies of kurstaki, dendrolimus, finitimus and aizawai, the molecular weights of main subusnits of crystal solubilized by alkaline solution were 1.3${\times}$105 and 6.5${\times}$104 while those of subsp. israelensis were 4${\times}$104 and 1,4${\times}$104. The degradation of lepidopteran toxic subspecies crystals by silkworm midgut protease showed 6.0-6.4${\times}$104 molecular weight and the pattern of degradation of subsp. israelensis crystals was similar to that of alkaline solution treatment. In the amino acid composition, aspartic acid in subsp. israelensis and glutiamic acid in the other four subspecies were the most abundant. The immunological characteristics of the crystals revealed that the antibody produced against the alkali-solubilized crystal protein of subsp. israelensis reacted with only its antigen, but the crystal antigens from the other four lepidopteran toxic subspecies did cross-react with each other as well as with their own homologous antisera.

• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.101-107
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• 1995

As the surfactants that were used in micellar reaction, emulsion polymerization and phase-transfer reaction etc. have the problems, the cleavable surfactant was converted to inactive compound after such as the reaction in the condition. Because 1, 3-dioxolane ring by ketal or acetal reactioc is lack of stability in acid condition, it is easily made to acid-hydrolysis. And cmc value of the surfactant is assumed $1.0{\times}10^{-5}mol/L$ and surface tension in cmc is 31 dyne/cm. Compared with other surfactant, this surfactant foam property is not better. But emulsion property was relatively good. According as acid-hydrolysis property was observed the interface tension change between aqueous solution and benzene by the variation of pH and time, this surfactant was made to hydrolysis within about 300minutes in pH 1${\sims}$4. Therefore this surfactant is expected to be a good emulsifier that has the bad foam property and the acid-hydrolysis property in acid condition.

• Food Science and Preservation
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• v.14 no.5
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• pp.457-461
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• 2007

We investigated the effects of both $CaCl_2$ treatment and modified atmosphere packaging (MAP) (compared with non-packaging on 'Fuji' apples from the Young-Joo region of Korea. Apples were dined into 5% (w/v) $CaCl_2$ solution for 15 min and then packaged with or without LDPE film (thickness: 0.025 mm) before cold storage at $0^{\circ}C$. Weight loss of applies in film packaging was lower than that of non-packaging applies, and the apple firmness resulting from $CaCl_2$ treatment and MAP was better than that of apples receiving control treatment. Also, $CaCl_2$ treatment and MAP resulted in improvements in titratable acidity, soluble solid content (SSC), and decay rate compared to control treatments. However, no significant differences in vitamin C content were found amongst apples receiving various treatment. the results suggest that a combination of postharvest calcium dipping and plastic film packaging may effectively preserve 'Fuji' apples, and that the combined treatment are better than either individual treatment.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.700-708
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• 1996

Electroless plating technique was utilized to flip chip bonding to improve surface mount characteristics. Each step of plating procedure was studied in terms pf pH, plating temperature and plating time. Al patterned 4 inch Si wafers were used as substrstes and zincate was used as an activation solution. Heat treatment was carried out for all the specimens in the temperature range from room temperature to $400^{\circ}C$ for $30^{\circ}C$ minutes in a vacuum furnace. Homogeneous distribution of Zn particles of size was obtained by the zincate treatment with pH 13 ~ 13.5, solution concentration of 15 ~ 25% at room temperature. The plating rates for both Ni-P and Au electroless plating steps increased with increasing the plating temperature and pH. The main crystallization planes of the plated Au were found to be (111) a pH 7 and (200) and (111) at pH 9 independent of the annealing temperature.

• Journal of the Korean Chemical Society
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• v.17 no.4
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• pp.275-285
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• 1973

The addition of one mole of aluminum chloride to three moles of sodium borohydride in tetrahydrofuran gives a turbid solution with enormously more powerful reducing properties than those of sodium borohydride itself. The reducing properties of this reagent were tested with 49 organic compounds which have representative functional groups. Alcohols liberated hydrogen immediately but showed no sign of hydrogenolysis of alkoxy group. Aldehydes and ketones were reduced rapidly within one hr. Acyl derivatives were reduced moderately, however, carboxylic acids were reduced much more slowly. Esters, lactones and epoxides were reduced readily than sodium borohydride or borane. Tertiary amide was reduced slowly, however, primary amide consumed one hydride for hydrogen evolution but reduction was sluggish. Aromatic nitrile was reduced much more readily than aliphatic nitrile. Nitro compounds were inert to this reagent but azo and azoxy groups were slowly attacked. Oxime was reduced slowly but isocyanate was only partially reduced. Disulfide and sulfoxide were attacked slowly but sulfide and sulfone were inert. Olefin was hydroborated rapidly.