• Journal of Korean Society for Atmospheric Environment
• /
• v.5 no.2
• /
• pp.42-54
• /
• 1989

This study was carried out to investigate the phenomena of acid precipitation. The pH value, electro conductivity and major anions (sulfate, nitrate and chloride) were measured by automatic acid rain monitor and ion chromatography at 5 points in Seoul area from Jan. to Dec. 1988. 1. The acidity of rainfall was in order winter (4.31) spring (4.77) fall (4.94) summer (5.31). Rainfall with a pH of less than 5.6 was appeared 83.2 percent. 2. The range of the highest appearence frequency rate both at Hannam-dong and Songsu-dong was from pH 4.6 to 5.0 and appeared 30.7 percent and 38.3 percent respectively, Bang-i-dong was 36.3 percent in the ranged from pH 4.1 to 4.5 and Guro and Ssangmun-dong were 26 percent and 30.3 percent in the ranged from pH 5.1 to 5.5 respectively. 3. The sulfate and nitrate ion concentration in earlier rainwater ranged from 0.1 ppm to 50.2 ppm and from 0.01 ppm to 15.8 respectively. The earlier rainwaters were generally more acidic than the after rainwaters. 4. The order of the major anion concentration in rainwater was $SO_4^{2-} > Cl^- > NO_3^-$ and the acidity of it was more effective by sulfate ion than others. The correlation between pH value and anions concentration was shown positive correlationship at Guro-dong and Bang-i-dong and negative correlation at Hannam-dong but not at the other sites.

• Journal of the Korean Ceramic Society
• /
• v.28 no.1
• /
• pp.46-52
• /
• 1991

The hydroxyapatite powders were prepared by the reaction of Ca(CH3COO)2$.$H2O and H3PO4 in aqueous solution. Effect of Ca/P mole ration and pH value on the powder characteristics were investigated. For phosphoric acid was dissociated to PO43- ion above pH 10, the preparation condition of hydroxyapatite by H3PO4 solution had this value. Dried powders were agglomerated each other. The mean agglomerate particle diameter was minimum when the condition was pH 11, Ca/P=1.75 and its specific surface area was 97㎡/g. All powders had poor crystallinity and small CO2. It prevented CaCO3 from using aspirator in preparation and maturing time. In most cases, hydroxyapatite was decomposed into ${\beta}$-TCP at more than 800$^{\circ}C$, into ${\alpha}$-TCP at 1200$^{\circ}C$. However non-decomposed hydroxyapatite was remained in Ca/P=1.85.

• Food Science of Animal Resources
• /
• v.25 no.2
• /
• pp.196-202
• /
• 2005

This study was carried out to investigate the effect of dietary Rhus verniciflua Stokes on the quality of Hanwoo (Korean cattle) beef during cold storage $(4^{\circ}C)$ after thawing. After 4 groups (3 heads/group) of 22 months-Hanwoo (Korean cattle) steen were fed a common basal diet with 0, 2, 4 and $6\%$ Rhus verniciflua Stokes (RVS) powder for 4 months prior to slaughter, samples of M semimembranous from 12 carcasses were stored at $-20^{\circ}C$ for 9 months. Crude fat was significantly lower in 4 and $6\%$ RVS treatments than in control (p<0.05). pH value was significantly higher in4 and $6\%$ RVS treatments than in control from 2 and 5 days (p<0.05). Thawing loss was not significantly different among the treatments but drip loss was significantly lower in 4 and $6\%$ RVS treatments than in control during storage (p<0.05). CIE $L^{\ast}$ value was significantly lower in RVS treatments than in control during storage (p<0.05) and CIE $a^{\ast}$ value was significantly higher in 4 and $6\%$ RVS treatments than in control (p<0..05). CIE $b^{\ast}$ value was significantly higher in control than in $6\%$ RVS treatment in 0 days (p<0.05) but it was significantly higher in $4\%$ RVS treatment than in control in 7 days (p<0.05). CIE $C^{\ast}$ value was significantly higher in $4\%$ RVS treatment than in control during storage (p<0.05) and CIE $h^0$ value was significantly lower in $4\%$ RVS treatment than in control (p<0.05). TBARS value of 2 days was significantly lower in 4 and $6\%$ RVS treatments than in control (p<0.05) but it was significantly lower in $4\%$ RVS treatment than the other treatments from 5 days (p<0.05). Surface MetMb concentration was significantly lower in RVS treatment than in control during storage (p<0.05) and it was significantly lower in $4\%$ RVS treatment than in the other treatments in 7days (p<0.05) but surface $R_{6.30}/R_{580}$ value was opposite to this result.

• Korean journal of food and cookery science
• /
• v.32 no.4
• /
• pp.458-465
• /
• 2016

Purpose: Bokbunja (Rub coreanus Miquel), mulberry and blueberry have been reported to have powerful anti-antioxidant and anti-aging activities. The purpose of this study was to compare the quality characteristics and antioxidant activities of gravy sauce added with Bokbunja, mulberry and blueberry. Methods: Quality characteristics pH, brix, color and sensory characteristics of samples were evaluated. Antioxidant activities of samples were compared using total phenol, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. Results: Mulberry juice showed significantly (p<0.05) higher values of pH and $^{\circ}Bx$ compared to Bokbunja and blueberry juice. Bokbunja juice also had significantly (p<0.05) higher value of Color-L value than mulberry and blueberry juice. The total phenol contents and ABTS cation radical scavenging activity of Bokbunja juice were 236.50 mgGAE/100 g and 61.66%, respectively, which were significantly (p<0.05) higher than those of blueberry and mulberry juice. pH value of gravy sauce added with mulberry (MBS) was 4.67, which was significantly higher than that of the control gravy sauce (GS) and gravy sauce added with Bokbunja (BJS) which had the lowest (p<0.05) pH value 4.33. $^{\circ}Bx$ of GS (13.50) was not significantly different from that of MBS and BBS. However, BJS showed the lowest (p<0.05) value $12.33^{\circ}Bx$. Total phenol contents and ABTS cation radical scavenging activity of BJS were 78.09 mgGAE/100 g and 14.47%, respectively, which were significantly (p<0.05) higher than those of MBS or BBS. Values of sensory characteristics color, sour aroma and sour flavor of BJS were significantly (p<0.05) higher value than those of other samples. Conclusion: Bokbunja juice and gravy sauce showed higher antioxidant activities and higher acceptance test compared to blueberry and mulberry. Thus, Bokbunja has the potential to be added to as high value products in the food industry.

• Journal of Radiation Protection and Research
• /
• v.1 no.1
• /
• pp.15-21
• /
• 1976

The present investigation was intended to study the state of Pm-147 in solution and its adsorbed state on membrane filters by varying the concentrations of Pm-147 solution and its pH. Also, the study on the coprecipitation of Pm-147 with $Fe(OH)_3$ was carried out by varying, amounts of $Fe(OH)_3$ and pH of the solution. The carrier-free Pm-147 exists in an ionic state of $Pm^{3+}$ in solution, and is adsorbed on membrane filter in filtration process. The adsorbed state of Pm-147 on the membrane filter shows various ionic state at a constant ionic strength of 0.1M NaCl, that is, $Pm^{3+}$ state exists until pH value of 5.0, then gradually $Pm(OH)^{2+}$ state appears between pH value of 5.0 to 6.0, and the state of $Pm(OH)_2^+$ and $Pm(OH)_3$ would be expected at the higher pH value of 6.0. Coprecipitation of Pm-147 on $Fe(OH)_3$ is an adsorption penomenon in an ionic state of $Pm^{3+}$ in acidic condition. At higher pH and larger amount of Fe carrier, the adsorbed state of Pm-147 shows $Pm(OH)^{2+}$ and $Pm(OH)_2^+$ state. As a results of the present studies, it is seen that the characteristic of carrier free radioisotopes is not due to the radioactivity, but due to the adsorption of ultramicroquantity of radioisopes. Therefore, the knowledge on the ultramicroquantity of radioisotopes could help for the solution of decontamination in handing and chemical procedure with radioisotopes.

• Journal of the Korean Wood Science and Technology
• /
• v.36 no.5
• /
• pp.42-48
• /
• 2008

This study was conducted to discuss the effects of hardener and extender contents on peak temperature, reaction enthalpy (${\Delta}H$), gelation time, viscosity change, and pH value in three types of UMF (urea-melamine- formaldehyde) resin with the help of perpHecT LogR meter, differential scanning calorimetry (DSC), and advanced rheometric expansion system (ARES), The results indicated that the pH value of Control A steeply decreased to 5,2 in the early stage but relatively remained constant thereafter as in Synthesis 1 and Synthesis 2, The peak temperature and time decreased as well, whereas ${\Delta}H$ and viscosity increased with the increase of hardener content. On the other hand, ${\Delta}H$ was not changed up to the extender content of 5% and then decreased with its further addition, And the pH value and peak temperature showed no change with the increase of extender content at the hardener content of 5% in three types of UMF resin, The effect of hardener content in this experiment, however, appeared more conspicuous in Control A than in the other two types of Synthesis 1 and Synthesis 2, These results might be caused by higher molecular weight with longer chains of methylene ($-CH_2-$) and methylene ($-CH_2-O-CH_2-$) ether bridges or much more branched chains in Control A.

• The Korean Journal of Physiology
• /
• v.9 no.1
• /
• pp.69-76
• /
• 1975

Cardiac performances were analyzed in intact turtle heart(Amyda japonica), perfusing with turtle Ringer-Locke's solution containing various hydrogen ion concentration, at several levels of arterial and venous pressure. 1. Ventricular work increased when venous pressure, or venous filling pressure increased, and also increased when arterial pressure increased. 2. The higher the arterial pressure, the lower the cardiac to output, for arterial pressure is the resistance to the ventricular blood flow. On the other hand, in specific arterial pressure, cardiac output was proportional to the venous filling pressure. 3. Heart rates did not change significantly during the perfusion with Ringel· solution of various pH. 4. In the heart Perfused with Ringer solution of various pH, ventricular work was the highest at PH 7.6 (at 6 $cmH_2O$ arterial pressure and 8 $cmH_2O$ venous pressure, the ventricular work was 63.09m$\cdot$cm). However, within the range of pH $7.1{\sim}7.6$, there were no significant changes in cardiac output and ventricular work. Below the level of pH 7.0, ventricular work decreased to less than 56% of maximium value (at $6cmH_2O$ arterial pressure and $8cmH_2O$ venous Pressure, ventricular work was 36.0$gm{\cdot}$ at pH 7.0). At pH 7.7 ventricular work decreased to less than 48% of maximum value (ventricular work: 30.0 $gm{\cdot}$). The nature of the cardiac performance at the various arterial and venous pressures was similar to that of normal heart. 5. Turtle heart seemed to be relatively insensitive to acid-base disturbances. The mechanism of negative inotropic effect of hydrogen ion was discussed.

• Korean journal of food and cookery science
• /
• v.12 no.4
• /
• pp.481-486
• /
• 1996

This study was compared with conventional kochujang and the preparation of saccharification kochujanf with the utilization of waste cooked rice, rice cake, bread. Saccharification kochuiang tested to estimated the pH, reducing sugar and changes of organic acid conients, sensory evaluation during the aging at 60 days. Moisture content were increased about B-10% nd crude fat contents were decreased about 20-40% during the aging at 60 days. Change of pH value of kochujang reduces gradually from pH 5.0 up to pH 4.7 during the aging. Total reducing sugar contents of saccharification kochujang reached maximum value at 50 days. The Products of organic acids of during aging were acetic acid, lactic acid, malic acid, tartaric acid and citric acid of the chief of source. Sensory evaluation conducted by fifteen students as panelists showed that were at 1% level significant difference 7 samples in color, flavour, apperance.

• Fashion & Textile Research Journal
• /
• v.3 no.1
• /
• pp.31-34
• /
• 2001

The color difference values of dyed fabrics with colorant in Eucommiae Cortex were as follows; One hour of dyeing depending on pH at $95^{\circ}C$ exhibited colors of dark brown, light brown, light beige and grey. The colors of wool, nylon and silk was darkest brown at pH 3 but light brown or yellow as pH increased. In all dyed fabrics the color was changed to darker brown as time prolonged, however; there was no further color change and value and chroma of wool declined. At pH 3, the increase in temperature turned colors of all dyed fabrics into dark brown from light yellow. As the result of repetitive dyeing, colors of all dyed fabrics gradually turned into darker brown. The methods of mordant resulted in color changes between light yellow and dark brown without various color changes.

• Korean Journal of Food Science and Technology
• /
• v.21 no.5
• /
• pp.662-668
• /
• 1989

The effect of four different humidities during smokehouse processing on cured color development color intensity, pH, residual nitrite, phenol deposition, TBA value and product yield of Canadian bacon was determined. High humidity resulted in high pigment conversion and lower pH. As the humidity was lowered, more residual nitrite remained, The highest humidity had the highest phenol deposition and TBA value. The lowest humidity had the highest yield.