• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.77-82
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• 2011

The surface of $Li[Ni_{0.35}Co_{0.3}Mn_{0.35}]O_2$ cathode was modified by $[Li,La]TiO_3$ coating using pH controlled coating solution. At low pH values (acidic solution), cathode powders, which is oxides, have a positive surface charge, whereas, they have a negative surface charge at high pH values. As a result, their charge could affect the formation of the coating layer on the surface of cathode powder. To determine the optimal pH value, the surface coating of the pristine powder was carried out at various pH values of the coating solution. The surface morphology of coated samples was characterization by SEM and TEM analyses. Impedance analysis and cyclic voltammogram presented that internal resistance of the cell was dependent upon the pH of coating solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.274-278
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• 1994

Correlation between pH and color of Kimchi during fermentation was investigated to visually evaluate the fermentation degree of Chinese cabbage Kimchi. Color "a" and 'H" values in the white part, "a", "H" and "C" values in the green part of the Kimchi showed a high correlation with pH, respectively. "a" and "H" values of Kimchi juice. "L" and "V" values of red pepper attached to kimchi had a high correlation with pH. The color of the white part was light greenish white in unripended Kimchi, but changed to redish in ripended kimchi. Green part changed from light green to redish green as ripening. Red pepper powder attached to kimchi showed redish color in unripening, but changed to yellowish re din over ripening.

• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.131-135
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• 2000

The inhibitory effect of various organic acids on the growth and survival of Escherichia coli O157:H7 in tryptic soy broth with 0.6% yeast extract at 37$^{\circ}C$ or 4$^{\circ}C$ was determined. Minimal inhibitory pHs of acetic acid, citric acid, fumaric acid, hydrochloric acid and lactic acid were 5.0, 4.0, 4.5, 4.0 and 4.5, respectively. Acetic acid (0.012 m) showed the strongest antimicrobial activity, based on the pH values or equivalent molar concentrations, followed by lactic acid (0.0006 M), fumaric acid (0.004M) and citirc acid (0.004 M), respectively, E. coli O157:H7 with an initial inoculum of {TEX}$10^{7}${/TEX} CFU/ml and {TEX}$10^{5}{/TEX} CFU/ml in tryptic soy broth supplemented with 0.6% yeast extract, acidified to target pH with citric, fumaric and lactic acids at 37$^{\circ}C$, was completely inactivated after 7 d and 5 d incubation, respectively, except for the acetic acid (9 d). The bactericidal effect decreased at the same pH when the incubation temperature a was reduced from 37$^{\circ}C$ to 4$^{\circ}C$. The pH values of 0.2% acetic (pH 5.1), 0.6% citric (pH 4.2) and 0.4% lactic acid (pH 4.3) in TSBYE were almost correspondent to the minimal inhibitory pH values on E. coli O157:H7 of acetic (pH 4.0), citric (pH 4.0) and lactic acids (pH 4.5).

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.375-378
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• 2001

This study was peformed to understand permeability characteristic of clays with various pH values. A serious of physical properties and permeability tests, consolidation tests was performed on a clay and a marine clay. Results of the study are as follows. As pH values were decreased, coefficient of permeability was increased because of increase in effective void caused by decrease in thickness of diffuse double layer besides change in soil structures and effective grain size. As pH values were increased, coefficient of permeability of marine clay was increased. Variation of coefficient of permeability of marine clay was increased. Variation of coefficient of permeability of marine clay was largely related because of higher clay contents.

• Journal of Plant Biology
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• v.10 no.1_2
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• pp.36-40
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• 1967

1. The effect of the pH value on P32 absorption of leaves of three forest trees under the water culture is investigated. 2. The degree of the P32 absorption to the pH value is quite different in each forest tree. 3. The phosphorus contents are proved higher in the leaves of Quercus accutissima(the saw shaped oak) than in the leaves of Pinus densiflora(the red pine) and Lespedeza bicolar (bush clover). 4. Larger contents of phosphorus are found in acidity plots than in alkalinity. The leaves of treated plot of the pH 4 (red pine), of the pH 5.0 (bush clover), and of the pH 5.0-6.5 (saw shaped oak) have a higher nutrient capital as indicated by P32 compared with that of the other pH values. 5. It is also noticed that P32 absorption capacity is decreased with the higher pH values. 6. The content of P of leaves shows the lowest value in the plot of the pH 6.5 (pine), of the pH 7.5(bush clover), and of the pH 9.0(saw shaped oak). It is also noticed that the red pine is to do very well in acid cultivation and then follow bush clover and saw shaped oak in the order.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.11
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• pp.1774-1780
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• 2009

The dyeing properties of cotton fabric with Inonotus obliquus are studied by investigating the effect of dyeing conditions on dye uptakes such as, the concentration of Inonotus obliquus, dyeing temperature, time, and pH values. In addition, the effects of mordants on dye uptakes and antibacterial activities are also investigated. The results are summarized as follows: The dye uptakes of dyed fabrics were increased gradually with an increasing concentration of Inonotus obliquus. K/S values were the highest when the dyeing temperature and time were at $60^{\circ}C$ and 60 minutes, respectively. As for the changes of pH values of dyeing solution, K/S values recorded the highest at pH3-pH5. Antibacterial activities of Inonotus obliquus dyeing solution showed a significant effect in dyed cotton fabric with mordanting.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.413-422
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• 2013

This study investigates the kimchi from Jangsu area (JSK) and its comparison with commercial kimchi (CMK). We conducted a sensory evaluation for the pH, titratable acidity, salinity, hunter's color values and mechanical characteristics of kimchi. The pH of JSK is significantly higher than CMK throughout the fermentation (p<0.001). At 15 days, JSK reached the stage of optimal maturity for pH 4.23~4.55 and CMK showed pH 3.96~4.00 as conditions after the optimal maturity (p<0.001). From the results of acidity analyses, CMK also showed higher acidity values than JSK (p<0.001), indicating that the rate of fermentation progress was faster in CMK. Salinity of JSK was a litter higher than CMK1 and CMK2 (p<0.001) and JSK indicated significantly higher L, a, b values during fermentation (p<0.001). Moreover, the textural values were significantly higher in JSK2 and JSK3 retaining hardness of the tissues. In the sensory assessment, the color, flavor, crispness, taste, and overall preferences were higher in JSK3 at 15 days and 30 days than CMK. Therefore, it seems necessary for recipe developments of kimchi with local characteristics in order to industrialize kimchi by using alpine crops at Jangsu area.

• Korean journal of food and cookery science
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• v.17 no.2
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• pp.117-122
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• 2001

Ground fresh garlic and 50% ethanol garlic extracts were added into ground porks in order to investigate their effects on pH, peroxide and TBA values of ground porks during storage at 4$\^{C}$. The grounded porks tested were devided into two groups of fresh and heated forks at 100$\^{C}$ for 10 minutes. A significant control effect of ground garlic and extracts was found on peroxide and TBA values during storage, particularly for those added with 20% ground garlic and 10% garlic extracts. The effects were maximum after storage of 4-6 days and then decreased thereafter The pH was generally decreased until 6 days followed by the increase. Addition of garlic and garlic extracts caused a little increase in pH and the pH changes were less than the changes of control. Eventhough the effects of garlic on pH, peroxide and TBA values were similar for both heated and fresh pork, heat treated one showed more changes than fresh pork.

• Advances in concrete construction
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• v.11 no.5
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• pp.419-428
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• 2021

The pH of cement-based materials (CBMs) is an important factor for their durability, sustainability, and long service life. Currently, the use of supplementary cementitious materials (SCMs) is becoming mandatory due to economic, environmental, and sustainable issues. There is a decreasing trend in pH of CBMs due to incorporation of SCMs. The determination of numerical values of pH is very important for various low and high volume SCMs blended cement mortars for the better understanding of different defects and durability issues during their service life. In addition, the effect of cement hydration and pozzolanic reaction of SCMs on the pH should be determined at initial and later ages. In this study, the effect of low and high-volume fly ash (FA) and ground granulated ballast furnace slag (GGBFS) cement mortars in different curing conditions on their pH values has been determined. Thermal gravimetric analysis (TGA) was carried out to support the findings from pH measurements. In addition, thermal conductivity (k-value) and strength activity indices of these cement mortars were discussed. The results showed that pH values of all blended cement mortars were less than ordinary Portland cement (OPC) mortar in all curing conditions used. There was a decreasing tendency in pH of all mortars with passage of time. In addition, the pH of cement mortars was not only dependent on the quantity of Ca(OH)₂. The effect of adding SCMs on the pH value of cement mortar should be monitored and measured for both short and long terms.

• YAKHAK HOEJI
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• v.19 no.1
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• pp.30-35
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• 1975

pKi values and sensitivity of acid-base indicators in the mixed solvent systems of water-alcohols and water-acetone at differential pH and in concentration media were determined by spectrophotometric method. When the concentration of the organic solvents were increased, the pKi values of sulfophthalein indicators, thymol blue and bromcresol purple, became larger whereas those of an axo indicator, methyl yellow, became smaller nad the pH values of the equivalent points of acids became smaller and the pH values of the equivalent points of acids became higher than those in the aqueous solution. potassium bicarbonate, a standard compound used in the organic solvent systems without a prerequisite procedure of expelling carbon dioxide by boiling.