• Macromolecular Research
• /
• v.15 no.5
• /
• pp.424-429
• /
• 2007

A procedure for the surface hydrolysis of an electrospun poly(${\epsilon}$-caprolactone) (PCL) fibrous scaffold was developed to enhance the adhesion and proliferation of osteoblasts. The surface hydrolysis of fibrous scaffolds was performed using NaOH treatment for the formation of carboxyl groups on the fiber surfaces. The hydrolysis process did not induce deformation of the fibers, and the fibers retained their diameter. The cell seeding density on the NaOH-treated PCL fibrous scaffolds was more pronounced than on the non-treated PCL fibers used as a control. The alkaline phosphatase activity, osteocalcin and a mineralization assay strongly supported that the surface-hydrolyzed PCL fibrous scaffolds provided more favorable environments for the proliferation and functions of osteoblasts compared to the non-treated PCL fibrous scaffolds use as a control.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.30 no.3
• /
• pp.13-21
• /
• 2012

This study was carried out to evaluate the stability of archival documents produced using papers. The properties of archival documents depend on the type of fillers of papers that are used such as fiber, non cellulose fiber, and mineral. The physio-chemical characteristics of archival documents were analyzed by employing acid hydrolysis against cellulose fiber substances. Fibers of Korean hand-made (Hanji), flex, and cotten papers showed higher pH and the degree of polymerization (DP) than wood fiber and mechanical fiber. Mechanical pulp containing 12.8% of lignin showed the greatest decrease of DP due to acid hydrolysis, and this resulted in increase of degree of aging. The filler found to clay and talc did not contain metal such as $Fe^{+2}$, $Fe^{+3}$, and $Cu^{+2}$. The alkaline metals such as Mg, Ca, and Ti showed greater resistance to acid hydrolysis.

• New & Renewable Energy
• /
• v.1 no.2 s.2
• /
• pp.60-72
• /
• 2005

The effect of alkaline pre-treatment on the solubilization of waste activated sludge(WAS) was investigated, and the biodegradability of WAS, pretreated WAS, [PWAS], food waste and two types of mixture were estimated by biochemical methane potential [BMP] test at $35^{\circ}C$. The biodegradability of PWAS and mixture waste were significantly improved due to the effect of alkaline hydrolysis of WAS. An alkaline pre-treatment was identified to be one of the useful pre-treatment for improving biodegradability of WAS and mixture waste. In high-rate anaerobic co-digestion system coordinate with an alkaline pre-treatment in process, the digesters were operated at the HRT of 5, 7, 10 and 13 days with a mixture of FW $50\%\;and\;PWAS\;50\%,\;$In term of $CH_4$ content, VS removal and specific methane production [SMP] which are the parameters in the performance of digester, the optimum operating condition was found to be a HRT of 7 days and a OLR of 4.20g/L-day with the highest SMP of 0.340 L $CH_4/g$ VS.

• Journal of Microbiology and Biotechnology
• /
• v.15 no.4
• /
• pp.745-748
• /
• 2005

A phytase from Aeromonas sp. LIK 1-5 was partially purified by ammonium sulfate precipitation and DEAE-Sephacel column chromatography. Its molecular weight was 44 kDa according to SDS-PAGE gel. Enzyme activity was optimal at pH 7 and at $50^{\circ}C$. The purified enzyme was strongly inhibited by 2 mM EDTA, $Zn^{2+},\;Co^{2+},\;or\;Mn^{2+}$, and activated by 2 mM $Ca^{2+}$. The K_m value for sodium phytate was 0.23 mM, and the enzyme was resistant to trypsin. The N-terminal amino acid sequence of the phytase was similar to that of other known alkaline phytases. The phytase was specific for ATP and sodium phytate, which is different from other known alkaline phytases. Based on the substrate specificity, the phytase may therefore be a novel alkaline phytase.

• Journal of the Korean Chemical Society
• /
• v.24 no.6
• /
• pp.469-472
• /
• 1980

• YAKHAK HOEJI
• /
• v.43 no.3
• /
• pp.320-327
• /
• 1999

Six novel aryl alkanoic acid derivatives as potential nonsteroidal antiinflammatory and analgesic compounds, were prepared through consecutive reactions of Ullman ether synthesis, $NaBH_4$ reduction ; bromination ; $SN_2$ reaction with nitrile and alkaline hydrolysis of the nitrile.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2010.03a
• /
• pp.121-122
• /
• 2010

• Applied Biological Chemistry
• /
• v.13 no.3
• /
• pp.223-229
• /
• 1970

1. The preparation and some enzymatic properties of crude alkaline protease from a thermophilic mold, Myriococcum sp. was investigated. 2. Optimum pH for the hydrolysis of casein was 9.0 at $50^{\circ}C$ for 10 minutes. Optimum temperature was $55^{\circ}C$ at pH 9.0 for 10 minutes. The enzyme was highly stable at the range of pH 6.0 to 11.0 at $30^{\circ}C$ 3. The alkaline protease in the culture filterate was isolated two fractions by elution column chromatography on DEAE-Cellulose.

• Journal of the Korean Chemical Society
• /
• v.41 no.6
• /
• pp.299-303
• /
• 1997

The rate constants($k_{OH}$) for the alkaline hydrolysis of the 4-substituted phenyl ethyl benzylphosphonates were determined in various buffer solutions by UV(Vis spectrophotometer. The activation entropies of the title reactions show negative values and this result is not consistent with a dissociative mechanism (EA) for which a positive or slightly negative value of the entropy of activation should be expected. An associative mechanism(AE) is favorable because the negligible negative charge is generated on the leaving group in the rate determining step from a good Hammett relationship(ρ=1.89). By the results of a kinetic study, we conclude that a dissociative mechanism is not proceeded in the title reactions.

• Applied Chemistry for Engineering
• /
• v.3 no.1
• /
• pp.119-129
• /
• 1992

The rates of mass transfer with the alkaline hydrolysis of ethyl acetate and n-butyl acetate were measured by using a modified Lewis cell. The rates of mass transfer with chemical reaction were independent of the speed of agitation, and the reaction enhancement factors were independent of the ionic strength. The second order reaction rate constants of ethyl acetate and n-butyl acetate could be obtained from an approximate solution of a diffusion equation by film theory, and their values were $0.041m^3/kg\;mol{\cdot}s$ and $0.338m^3/kgmol{\cdot}s$, respectively.