• Microbiology and Biotechnology Letters
• /
• v.33 no.2
• /
• pp.106-111
• /
• 2005

To investigate the substrate variety of a putative non-metal dependent isomerase, the tagatose-6-phosphate isomerase (E.C. 5.3.1.26) structural genes (lacB; 510bp and lacA; 430bp) of Staphylococcus aureus were subcloned and co-expressed. Based on the substrate configuration, various aldoses were surveyed for substrate of ketose isomerization. Among the 10 aldoses tested, D-ribose and D-allose were isomerized by the enzyme. The subunit A and B showed more than $95\%$ activity for D-ribose and $75\%$ for D-allose in the presence of 1mM EDTA compared with non-EDTA conditions, which implying tagatose-6-phosphate isomerase is a non-metal dependent isomerase. Each of subunit A or subunit B alone showed no activity for any of the substrates tested. The affinity constant ($K_m$) of tagatose-6-phosphate isomerase against D-ribose and D-allose were 26 mM and 142 mM, respectively.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.6
• /
• pp.1817-1824
• /
• 2014

The adsorption characteristics of chromium (VI) and phosphate on calcined Mg-Al-$CO_3$ layered double hydroxides (CLDH) were investigated in single and binary systems. A series of batch experiments were performed to study the influence of various experimental parameters. In this study, CLDH exhibited a high adsorption capacity for Cr (VI) and P in a single system. The experimental data were close to the theoretical adsorption capacity given by the Langmuir isotherm, the calculating adsorption capacities of Cr (VI) and P were up to 70.42 mg/g and 97.09 mg/g, respectively. It was found that the initial pH was approximately 6 and it took 24 h to reach equilibrium when P and Cr (VI) were added simultaneously. The experimental data were best fitted by a pseudo-second-order kinetics model. Competitive adsorption between Cr (VI) and P existed in the binary system. The presence of Cr (VI) had no significant influence on P adsorption. However, the suppression of Cr (VI) adsorption was obvious when the initial concentration of P was up to 10 mg/L with a concentration of 0.5 g/L of CLDH.

• Journal of the Korean Ceramic Society
• /
• v.37 no.6
• /
• pp.583-588
• /
• 2000

Antioxidation characteristics of carbon at high temperature with the co-addition of Al and Si powder in Al2O3-C system refractory were analyzed. The use of surface-modified phosphate carbon as a starting material was found to be very effective in improving the mixing effect of raw materials and antioxidation behavior of carbon. In particular, this effect was dominant at higher temperatures than 130$0^{\circ}C$.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.125-126
• /
• 2009

In this study, we report the room temperature synthesis and luminescence properties of white-light-emitting Rb(V,P)$O_3$. The vanadate phosphor, RbV$O_3$, was synthesized by simple mixing of $RbCO_3$ and $V_2O_5$ at room temperature in air. New direct room temperature solidstate reaction is a cost-effective method to synthesize the above luminescent materials.

• 대한치주과학회:학술대회논문집
• /
• 2007.11a
• /
• pp.101-102
• /
• 2007

• Journal of Electrochemical Science and Technology
• /
• v.2 no.4
• /
• pp.187-192
• /
• 2011

Photoelectrochemical performances of ZnO electrodes are enhanced by coupling with cobalt-based catalyst (CoPi) in phosphate electrolyte (pH 7). For this study, hexagonal pillar-shaped ZnO nanorods are grown on ZnO electrodes through a chemical bath deposition, onto which CoPi is deposited with different photodeposition times (10-30 min). A scanning electron microscopic study indicates that CoPi deposition does not induce any change of ZnO morphology and an energy-dispersive X-ray spectroscopic analysis shows that inorganic phosphate ions (Pi) exist on ZnO surface. Bare ZnO electrodes generate the current of ca. $0.36mA/cm^2$ at a bias potential of 0.5 V vs. SCE, whereas ZnO/CoPi (deposited for 10 min) has ca. 50%-enhanced current ($0.54mW/cm^2$) under irradiation of AM 1.5G-light ($400mW/cm^2$). The excess loading of CoPi on ZnO results in decrease of photocurrents as compared to bare ZnO likely due to limited electrolyte access to ZnO and/or CoPi-mediated recombination of photogenerated charge carriers. The primary role of CoPi is speculated to trap the photogenerated holes and thereby oxidize water into molecular oxygen via an intervalency cycle among Co(II), Co(III), and Co(IV).

• Journal of Periodontal and Implant Science
• /
• v.38 no.2
• /
• pp.171-178
• /
• 2008

Purpose: The aim of this study was to evaluated biphasic calcium phosphate applied in surgically created 1-wall periodontal intrabony defects in dogs by histometrical analysis. Material and Method: Critical sized($4\;mm\;{\times}\;4\;mm$), one wall periodontal intrabony defects were surgically produced at the proximal aspect of mandibular premolars in either right and left jaw quadrants in four canines. The control group was treated with debridement alone, and experimental group was treated with debridement and biphasic calcium phosphate application. The healing processes were histologically and histometrically observed after 8 weeks. Results: In biphasic calcium phosphate group, more new bone and cementum formation, less epithelium and connective tissue attachment were observed compared to other groups. But there was no statistical significance. Conclusion: Though the statistically significant difference could not be found, it seemed that there was more new bone and cementum formation with applying biphasic calcium phosphate in 1 wall intrabony defects in dogs by preventing junctional epithelium migration.

• Korean Journal of Food Science and Technology
• /
• v.19 no.1
• /
• pp.75-80
• /
• 1987

In order to prevent browning during drying of garlic flakes, the effect of dipping in phosphate complex solution prior to drying on the development of brown pigment in the flakes were studied. The browning color development during drying of the flakes was greatly dependent on phosphate complex concentration and their dipping time. A reciprocal relationship between browning color formation and reducing sugar content of dried garlic flakes was found. The browning color development during drying of the flakes was effectively impeded by dipping in 0.3% phosphate complex solution for 3 minute. The reduction of pyruvate content during drying of the flakes was greatly influenced by phosphate complex concentration and drying temperature, and a maximum retention was acieved by 3 minute dipping in 0.2-0.3% phosphate complex solution. The dried yield of the flakes dipped in phosphate complex solution was 1.62-1.75% lower than control and it was mainly caused by the dissolution of soluble solids during dipping.

• Progress in Superconductivity and Cryogenics
• /
• v.23 no.3
• /
• pp.20-25
• /
• 2021

Milking parlor wastewater contains high concentration suspended solid (SS), nitrogen, and/or phosphate as well as organic compounds. A new biological wastewater process by magnetic separation, magnetic activated sludge (MAS) process, was applied to milking parlor wastewater treatment process. A three step wastewater treatment process of coagulation sedimentation / ammonia stripping (C/S), magnetic activated sludge process and contact oxidation (CO) was proposed for removal of these pollutants. First step, C/S process recovered 96% TN and 96% PO₄^3--P as resource for fertilizer from the wastewater. 81% biochemical oxygen demand (BOD) in wastewater was removed after MAS process. As a results, all pollutant concentrations satisfied Japanese effluent standards. Most of residual BOD and SS were removed by the CO process. It was estimated that the proposed process could reduce the process space to 1/7.

• Korean Journal of Soil Science and Fertilizer
• /
• v.40 no.5
• /
• pp.405-411
• /
• 2007

This study was carried out to measure insoluble phosphorus fractions content fixed in different soil type and isolate a superior phosphate solublizing bacteria(PSB) producing free phosphate in citrus orchard soil. Distribution of insoluble phosphate fraction ordered Al-P>Ca-P>Fe-P in the investigated citrus orchards. Insoluble phosphate fraction such as Al-P, Ca-P, Fe-P were higher in volcanic ash than in non-volcanic ash soil. A PSB with high holo zone in PDA-P medium isolated from citrus orchard soil. This strain identificated by MIDI system as Bacillus sphaericus. The optimum growth of pH and temperature were at 4~5, $30^{\circ}C$, respectively. When Bacillus sphaericus cultured at $25^{\circ}C$, 150 rpm condition in LB broth medium included different phosphate. Bacillus sphaericus produced free phosphate in the culture broth medium from tricalcium-phosphate(207.0 ppm), aluminium phosphate(324.5 ppm) and hydroxyapatite(334.8 ppm) and Phosphatase activity of Bacillus sphaericus was higher at $35^{\circ}C$ culture condition than that of $25^{\circ}C$. Two type preparation inoculated Bacillus sphaericus made with carrier materials such as Bentonite, $CaCO_3$, Sodium alginate. Density of PSB in this preparation conserved at $10^5c.f.u.\;g^{-1}$ level during storage in different temperature condition for 7 month. It also showed that free phosphate produced at PDA-P medium.