• Korean Journal of Weed Science
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• v.16 no.4
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• pp.292-300
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• 1996

This experiment was conducted to investigate the factor of phytotoxicity for herbicides(bensulfuron methyl, pyrazosulfuron-ethyl, dimepiperate, molinate) on flood direct-seeded rice. The phytotoxicity of herbicides was evaluated under controlled environment condition. Bensulfuron methyl and pyrazosulfuron-ethyl reduced more rice growth, especially root growth on low temperature(20/$11^{\circ}C$) than high temperature(30/$22^{\circ}C$) cultivations. The phytotoxicity of bensulfuron methyl and pyrazosulfuron-ethyl were increased relatively by non-nutrient and nutrient solution. cultivation, respectively. The rice applied bensulfuron methyl and pyrazosulfuron-ethyl with pH 3.5, 5.5, 7.5 and 9.5 solution became low growth rate on low pH of pH 3.5 and 5.5 solution cultivation. Bensulfuron methyl application with pH 5.5 and pH 7.5 solution, and pyrazosulfuronethyl application with pH 7.5 and 9.5 solution reduced rice growth inhibition. The root growth of rice seeded in 6cm depth of water solution applied herbicides was suppressed by bensulftuon methyl and pyrazosulfuron-ethyl, the growth of shoot was suppressed heavily by dimepiperate and molinate, in particular dimepiperate suppressed about the growth of 90%. The phytotoxicity of pyrazosulfuron-ethyl became high on light clay soil of non-fertilizer condition and sand loam soil of fertilizer condition, bensulfuron methyl became high on sand loam soil.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.620-624
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• 1997

The conditions for color intensity and electron donating ability to $\alpha$,$\alpha$-diphenyl-$\beta$- picryl-hydrazyl (DPPH) of Bacillus subtilis DC-2 were investigated. Temperature, pH and cultivation time were chosen as three factors, and the optimal conditions of color intensity and DPPH was determined with response surface methodology. Color intensity was affected by cultivation temperature(p<0.1). DPPH was influenced by cultivation temperature(p<0.05) and pH(p<0.1). But cultivation time was affected neither color in- tensity nor DPPH. Optimal conditions of color intensity with Bacillus subtilis DC-2 were appeared at cultivation temperature of 39.$25^{\circ}C$, pH 8.83 and cultivation time of 84.41hrs. Optimal conditions of DPPH with Bacillus subtilis DC-2 were revealed at cultivation temperature of 39.19$^{\circ}C$, pH 8.84 and cultivation time of 82.21hrs.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.2
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• pp.121-126
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• 1993

The behaviors of inorganic nitrogen derived from solid animal waste in soil has been received too much concern partly because nitrate which occurred from nitrification can act as a pollutant to soil and groundwater and partly because the loss of nitrogen from surface soil by downward movement of water is disadvantageous in the view of plant nutrient. This present study was conducted to get fundamental imformations on nitrogen behavior and to provide improved basical concepts on the management of animal waste. Fresh or fermented pig manure was mixed with a sandy loam soil in the ratio of 2:1(soil:pig manure), packed into test tube and incubated at $30^+/-1^{\circ}C$ for 8 weeks under aerobic- or anaerobic condition. Sample tubes were taken at the one week interval and analyzed on pH, the amount of $CH_4$ produced under anaerobic condition and inorganic nitrogen. The pH of soil treated with fresh pig manure under anaerobic condition was lowered by 1.87 unit compared to that of under aerobic condition, but at the treatment with fermented pig manure, pH change was very little between aerobic and anaerobic condition. The coefficients of regressional equations which were obtained from pH and incubation time were -0.114 in fresh pig manure and -0.089 in fermented pig manure, and the extent of pH decrease due to incubation was greater in fresh pig manure than that of fermented pig waste. No differences in the amounts of $CH_4$ produced under anaerobic condition between fresh and fermented pig manure was observed until 3 weeks of incubation, however, after that the amount of $CH_4$ produced in fresh pig manure was abruptly increased and cumulative amont of $CH_4$ was reached 8.6 mole/g. K values on $CH_4$ production in fresh and fermented pig manure was 0.211 mole/g/day and 0.046 mole/g/day, respectively, for 5 weeks from the 3rd to the 8th week. $NH_4-N$ concentration at aerobic condition with fresh pig manure treatment was lowered by passing time of incubation, but $NO_3-N$ concentration was elevated from 11.2 ppm at initial state to 67.3 ppm after incubation and this trend on $NH_4-N$, $NO_3-N$ concentration was very similar to the treatment of fermented pig manure. While $NH_4-N$ concentration under anaerobic condition was greatly increased. $NO_3-N$ concentartion was not only very low but also no great changes, that was ranged from 4 to 8 ppm.

• KSBB Journal
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• v.10 no.2
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• pp.176-182
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• 1995

The environmental and physiological factors affecting the production of exopolysaccharide (Methylan) and Poly-${\beta}$-hydroxybutyrate(PHB) by Methylobacterium organophilum were investigated. The maximum PHB content was obtained at $38^{\circ}C$ whereas maximum polysaccharide concentration was $3.54g/\ell$ at $30^{\circ}C$. Optimum pH was pH 7-8 for PHB production and pH 6-7 for polysaccharide production, respectively. Under the condition of $Mo^{2+}, Mg^{2+} or Mn^{2+}$ limitation with nitrogenlimitation, the PHB accumulation was increased, whereas the polysaccharide production was decreased as compared with that of solenitrogenlimitation. Under the condition of sole K+ limitation, cell growth was significantly inhibited and no polysaccharide was produced. However, the PHB content was as high as 60% of dry cell weight. Effect of C/N ratios (methanol/ammonium) in the feeding solution was examined for the simultaneous production of polysaccharide and PHB. The higher ratio of C/N showed the lower cell growth, higher content of PHB in cells, and higher yield of polysaccharide.

• Food Science and Preservation
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• v.19 no.2
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• pp.216-222
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• 2012

The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.479-485
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• 2009

In this study, basic physical properties were measured for ASCO EQ85 cationic surfactant of triethanolamine-ester quaternary ammonium salt and effect of pH on softening performance on fabrics was investigated using zeta potential measurement and adsorption experiment by quartz crystal microbalance. The CMC of the surfactant was near $3{\times}10^{-3}mol/L$ and the surface tension at CMC was about 40 mN/m. The interfacial tension measurement between 1 wt% aqueous solution and n-dodecane measured by spinning drop tensiometer showed that interfacial tension slightly increased with an increase in pH but the equilibration time was not affected by pH. The surfactant adsorption was found to increase with an increase in surfactant concentration and was also affected by pH of surfactant solution. The friction factor for fabrics treated with ASCO EQ85 surfactant was shown to increase with pH and better softening effect was found under acidic conditions. Half-life for foams generated with ASCO EQ85 surfactant solution increased with pH, which indicated an increase in foam stability with pH.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.19-25
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• 1996

A fundamental study on composting garbage was performed in a laboratory scale of a high-speed composting reactor. Major parameters were moisture content, temperature and C/N ratio. The results are as follows; pH of the compost was the highest at moisture 60% and anaerobic condition occurred at 70%. It was, also, found that C/N ratio, caused a nitrogen loss due to an occurrence of plentiful $NH_3$. Under controlling Temperature, pH was the highest at $60^{\circ}C$ and an inverse effect for Composting occurred under excessive Temperature as pH at $70^{\circ}C$ was lower than that of soil. The variation of pH and C/N ratio was the lowest when C/N ratio was 25. The results obtained from composting garbage revealed that the best condition of composting occurred under 50 to 60% of moisture content, $60^{\circ}C$ of temperature, and 25 of C/N ratio. It is believed that composting may be finished with in 56 hours if an optimal condition is setting up.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.317-321
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• 2004

We selected a solvent for producing antioxidants from sporophyll of Undaria pinnatOptimum extraction condition for antioxidant ability(Y) of sporophyll of U. pinnatifida was investigated using response surface methodology(RSM). A compound central design was used with variables ($X_1$)temperature($^{\circ}C$) (3.4; 20; 60; 100; 116.6); ($X_2$) pH(1.8; 3; 6; 9; 10.2) and ($X_3$) treatment time(min) (1.7; 10; 30; 50; 58.3). Antioxidant activities were increased with decreasing pH and increasing temperature. The optimal extraction conditions for antioxidant ability(Y) of sporophyll of U. pinnatifida were found to be temperature $51.55^{\circ}C$, pH 4.2 and treatment time 28.2 min. Among the variables tested, pH showed greater significant facin extraction of antioxidants from sporophyll of U. pinnatifida.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.129-138
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• 1980

The formation constants of the mixed-ligand complexes in the Cd(II), Cu(II) and Pb(II)-Trien-OH system were studied by polarograph. The formation constant $(log{\beta}_{ij})$ was determined at $25^{\circ}C$ in the ionic strength of 0.1. It was also confirmed that the mixed ligand complexes in this system were formed above pH 10.2, 10.5 and 9.0 for Cu(II), Cd(II) and Pb(II) by the calculation of the distribution for complexes at the various pH. Masking of Cd(II) by conversion to anionic EDTA-complexes has been used to separate Cu(II) from Cd(II) through passage of a combined Trien-EDTA solution on an cationic resin column. The optimal condition for the separation of Cu(II) from Cd(II) is confirmed at the pH range above 9.0, not only by considering the theoretical equation of the conditional-exchange-constant of metal on the cation exchange resin,but also by calculating the distribution of the mixed ligand complexes in the resin at the various pH with computer. By analyzing the synthetic sample of Cu(II) and Cd(II) with a EDTA masking at pH 9.5, it is found that the results of the experiment are satisfied with the theoretical value.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.167-172
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• 2009

The principal objective of this study was to determine the optimum manufacturing conditions of egg white with high foaming property for the production of angel food cakes. The egg whites were desugarized and powdered at predetermined pHs and drying temperatures. The physicochemical properties of the produced cakes were measured and sensory evaluations were conducted on a 9-point scale. The volume and textural properties of cakes produced from spray-dried egg whites did not differ from those of the cakes prepared from the control egg whites. The pH of batter and the specific gravity of foam and batter with egg white powder at pH 6.74/66.5$^{\circ}C$ did not differ from those of the control, whereas the one prepared with commercial powder lost the characteristics of cake to a significant degree. The overall acceptance scores of egg white powder of pH 6.74/66.5$^{\circ}C$ and commercial powder were 6.25 and 2.33 as compared to the control (6.42). These results indicate that the egg white powder that was desugarized, pH-adjusted to 6.74, and dried at 66.5$^{\circ}C$ might be utilized to prepare angel food cakes with the desirable physicochemical and sensory attributes.