• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.296-298
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• 2005

Hydrogen generation by the hydrolysis of aqueous sodium borohydride $(NaBH_4)$ solutions was studied using IRA-400 anion resin dispersed Pt. Ru catalysts and Lithium Cobalt oxide $(LiCoO_2)$ supported Pt, Ru and PtRu catalysts. The performance of the $LiCoO_2$ supported catalysts is better than the ion exchange resin dispersed catalysts. There is a marked concentration dependence on the performance of the $LiCoO_2$ supported catalysts and the hydrogen generation rate goes down if the borohydride concentration is increased beyond $10\%$. The efficiency of PtRu- $LiCoO_2$ is almost double that of either Ru-$LiCoO_2$ or Pt-$LiCoO_2$ for $NaBH_4$ concentrations up to $10\%$.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.171-186
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• 1992

Lipolytic characteristics of candia cylindracea lipase was studied by various triacylglycerols with different fatty acyl chains as substrate. The substrate was emulsified with gum arabic and the rate of hydrolysis was determined by pH stat method. The effects of gum concentration, pH, temperature, and $Ca^{2+}$ ion on the enzyme activities were examined. The results show that the effect of these factors are markedly depending on the structurla nature of substrates. The triolein was the best substrate among tested. Present study demonstrates that for characterization of lipolytic enzymes, it is critically important to select proper substrate and activator.r.

• Journal of the Korean Ceramic Society
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• v.31 no.10
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• pp.1209-1217
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• 1994

Monodispersed alumina-zirconia fine powders were prepared by controlled hydrolysis of alkoxides. These powders and the sintered bodies were characterized. Aluminium alkoxide and zirconium alkoxide were dissolved into complex solvent with butanol and n-propanol, and by acetonitrile added hydrolytic solution, hydrolysis rate was controlled. The oil, as a dispersant, was added in hydrolytic solution, and then prepared powders were nano-sized and well-monodispersed. In the case of hydroxypropyl celluose (HPC) as a dispersant, it was added in complex solution with butanol and iso-propanol, sub-micrometer sized and well-monodispersed powders could be prepared. The value of relative density (R.D.) and tetragonal phase fraction of zirconia in the sintered body made by nano-meter sized powders were respectively higher than those in the case of sub-micrometer sized one.

• Journal of Life Science
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• v.11 no.2
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• pp.138-143
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• 2001

Marsh calm(Corbicular elatior)with a short-term storage in raw and a law-rate of utilization has been increasing the needs to develop new marsh calm processing products for a temporary mass treatment and long-term distribution, Therefore the processing conditions of marsh calm beverage using proteolytic enzyme hydrolysis were investigated. A partial hydrolysis at 6$0^{\circ}C$ for 1 hour after adding 3% Alcalase as more effective than a hot water extraction to develop taste compounds from the marsh calm. The result of ommission test showed that nucleotides and their related compounds were contributed in the taste of the marsh calm hydrolysates rather than free amino acids. The taste of the hydrolysates was produced by association with these compounds rather than only one compound s the hydrolystes taste differently for the control when one of these compound was omitted. The hydrolysates were fractionated to molecular weight below 500 dalton to eliminate bitter taste and to improve it flavor from the hydrolysates, 0.05% bay leaf was more effective to improve the odor than other herbs.

• YAKHAK HOEJI
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• v.34 no.5
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• pp.334-340
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• 1990

The bioequivalence of Mandol and Mancef (cefamondole nafate injection preparation) was investigated for 8 healthy human volunteers. Cefamandole nafate hydrolysis to cefamandole base in the blood and shows antibacterial activity. As the rate of the hydrolysis can be varied according to the buffer used in the preparation, the bioequivalence of cefamandole nafate I.V. was studied. A new HPLC method, the column switching technique, was developed and used for the simultaneous determination of cefamandole and cefamandole nafate in the plasma and in the urine. There were no statistically significant difference in between Mandol and Mancef for the parameters of AUC and Cp 0.25 hr even through the power of the test was not enough.

• Textile Coloration and Finishing
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• v.10 no.2
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• pp.1-7
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• 1998

In this study, PET fabric was hydrolyzed with NaOH using the Tank m/c and Liquor-flow m/c to determine the alkali hydrolysis properties of PET fabrics. The results were as follows ： The weft density and tensile strength of PET fabrics hydrolyzed with Liquor-flow m/c were higher than those hydrolyzed with Tank m/c in case of less than 10％ of weight loss. However, above 10％ of weight loss, reverse phenomenon was showed. K/S value of hydrolyzed PET with Liquor-flow m/c was higher than that with Tank m/c above 10％ of weight loss. It was observed that the micropores of PET surface were collapsed due to physical force(abrasion and collision) during hydrolysis. Bending rigidity of hydrolyzed PET fabric was about 32％ and 40％ of bending rigidity of warp and weft direction of untreated fabric at 7％ of weight loss, respectively. Above 7％ of weight loss, decrease rate was decreased.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.114-120
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• 1994

Esterolysis reactions of PNPDPP (p-nitrophenyldiphenylphosphate) by DCI ( dichloroisocyanuric acid sodium salt) in borate buffer pH8.0 micellar phase were studied. The rate of hydrolysis reaction was rapidly increased by adding cationic surfactants, CTAC (cetyltrimethylammonium chloride) or CTAB (cetyltrimethylammonium bromide), to the DCI solution. Especially in CTAB micellar system, the N-Cl bond of DCI was transformed to the N-Br bond during the reaction.

• Korean Journal of Pharmacognosy
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• v.7 no.2
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• pp.85-93
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• 1976

Since cellulose is the only organic material that is annually replenishable in very large quantities, we must explore ways to utilize it as a source of energy, food and chemicals. For the utilization of this resource, it is first enzymatic hydrolyzed to glucose, then the glucose can be used as a food, converted single cell protein by microorganism, fermented to clean burning fuel and other chemicals. Cellulolytic enzyme, cellulase, consists of two or three major components, $C_1-cellulase$, $C_x-cellulase$ and ${\beta}-glucosidase$. $C_x-cellulase$ are fairly common but $C_1-cellulase$ are quite rare. Trichoderma viride is the best source of active cellulose, especially $C_1-enzyme$. Saccharification rate of cellulose in greatly influenced by the degree of crystallinity and extent of lignification. But by the pretreatment the substrate with cellulose swelling agent, delignifying reagent and physical treatment, the degree of saccharification is enhanced. Thus, glucose syrups of 2 to 10% concentration are realized from milled newspaper. The enzymatic hydrolysis of such energy rich material, such as cellulose, to glucose is technically feasible and practically achievable on a very large scale.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.1-7
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• 2014

Dissolving part of xylan and lignin in lignocellulosic biomass by base can be used as pretreatment technique. Cork oak was pretreated with sodium hydroxide solution and the pretreatment effects were evaluated with two critical factors - NaOH concentration and pretreatment temperature. Some of xylan and lignin were removed by base pretreatment. At $90^{\circ}C$ and 13% NaOH pretreatment, 22.0% of lignin and 78.8% of xylan removed by base treatment. Enzymatic hydrolysis of cork oak which was pretreated at higher temperature or concentration was further improved. After pretreatment of cork oak with 13% NaOH at $90^{\circ}C$, the conversion rate of cellulose to fermentable sugars were reached up to 91.3%. At ethanol fermentation with enzymatic hydrolysate from different pretreatment conditions, all enzymatic saccharification liquids were well fermented by Saccharomyces cerevisiae.

• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.102-107
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• 1990

The reaction of thiazoline-azetidinone (7) with $I_2$ in $CH_2Cl_2-H_2O$ gave directly 3-iodo-3-methylcepham (4). A phase transfer catalyst considerably increased the reaction rate. Similar to the hydrolysis of thiazoline-azetidinone (7) under a weak acidic condition, thiazole (10) was given as major product in the treatment with 0.1 eq. of iodine. The difference between cyclization reaction and hydrolysis could be explained in terms of solvents, the amount of iodine and the nature of thiazoline-azetidinones (7).