• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.220-224
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• 1991

Six reagents (water, citric acid, phosphoric acid, oxalic acid, acetic anhydride and maleic anhydride) were evaluated for their effectiveness is degumming rice bran oil. All chemical reagents tested were found to be significantly more effective than water in removing phosphatides from crude rice bran oil. Especially acetic anhydride and phosphoric acid were effective in reducing phosphorous levels (92.5% and 93.3% removeal, respectively). Nonhydratable phospholipids, lysophosphatidyl choline, were removed more effectively by the chemical reagents than by the water degumming. The major phospholipid(PL) components were phophatidyl choline. Oleic, linolieic and palmitic acids were the major fatty acids of PL in rice bran acetone insolubles(AI). The AI recovered by acetic anhydride degumming produced the most stable emulsions. However, the AI obtained from phophoric acid or oxalic acid treatments had very poor emulsifying properties.

• Resources Recycling
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• v.14 no.5 s.67
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• pp.18-23
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• 2005

Recovery of phosphoric acid from waste acid mixture of acetic, nitric and phosphoric acid has been attempted by using solvent extraction method. In this work, organic phosphate was used as an extraction agent. The effect of phosphate concentration, agitation speed and time on the solvent extraction of acetic and nitric acids has been investigated. The optimum concentration of phosphate for preferential extraction of acetic and nitric acids from waste acid was found to be about 50% irrespective of agitation speed and time. Purified phophoric acid was recovered from extraction residue at 1/3 of A/O ratio and 6th stage of extraction stage, which is well consistent with the value calculated by using McCabe-Thiele diagram.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.535-546
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• 1992

The molten carbonate fuel cell(MCFC) has been under Intensive development for the last decade as a second generation fuel cell. The advantages of the MCFC over the phophoric acid fuel cell are higher efficiency, its ability to accept CO and $H_2$ as a fuel, lower material costs, and high operating temperature making internal reforming possible. These features, along with low atmospheric emissions, will open up a significant market as an attractive means of developing highly efficient power plant. This article reviews a status of the MCFC research and development, a principle of the MCFC, and cell and stack technology including the status of electrodes, matrices and electrolytes. Several technical difficulties which must be resolved to be commercialized art mainly focused.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.506-510
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• 1996

The stability of prickly pear color as affected by pH, metal ions, sugar and acids was studied. The color of prickly pear was most stable at pH 4 and 5. Metal ions (Fe, Cu) at a level of 100 ppm caused a decrease in stability compared to that of the control, whereas pigment of prickly pear was stable at 100 ppm of Sn ion And the color of prickly pear was stable at 0.15 M fructose. Both 100 and 500 ppm ascorbic acid had the greatest effect on stability, while citric acid, phosphoric acid and tartaric acid had no effect on stability compared to that of the control. Based on the data presented, it was concluded that under selected conditions prickly pear pigment should find application as natural food colorants.

• Membrane Journal
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• v.14 no.2
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• pp.117-125
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• 2004

Proton exchange membrane composed of PVA/PAM/ZrP was prepared and effect of PAM and ZrP contents on properties and performance of the membrane were investigated. PAM as a crosslinking agent was mixed into PVA solution with different concentration (7∼11 wt%) and the PVA/PAM solution was cast to prepare PVA/PAM crosslinked membrane. The membrane was treated in the solution of zirconyl chloride and phophoric acid to make a PVA/PAM/ZrP composite membrane. Methanol permeability, ion conductivity, swelling and ion exchange capacity of the membranes with different ZrP concentration were $10^{-8}∼l0^{-6}$ $\textrm{cm}^2$/sec, $10^{-3}~10^{-2}$ S/cm, 0.26∼1.17 g $H_2O$/g membrane and 2.59∼5.1 meq/g membrane, respectively. Hethanol permeability and ion conductivity of the PVA/PAM/ZrP membrane were improved by 18% and 23%, respectively, compared to those of the PVA/PAM membrane.

• Korean Journal of Medicinal Crop Science
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• v.19 no.4
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• pp.227-232
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• 2011

The roots of Platycodon grandiflorum has been widely used as a crude drug or a food stuff. Unfortunately, the output and the quality is not regular and highly dependent on the cultivation area and cultivation method. Therefore, seedling cultivation study of this plant under structure with various fertilizer supply was performed. As a result, significant big difference between ammonia nitrogen and nitrate nitrogen content was shown in the root at seedling stage while the difference was not significant in the aerial parts. Fresh weight of the root (7.73 g plant$^{-1}$) was higher in the group treated with three major nutrients (N, P and K) than in those treated with three major nutrients and calcium or magnesium or both calcium and magnesium, and non-treated group (2.69 g plant$^{-1}$). Total nitrogen content was recognized to be significantly correlated with root weight, plant height, number of leaves and weight of aerial parts. Ammonium nitrogen content was more correlated the growth of P. grandiflorum than nitrate nitrogen. For phosphoric acid, significant correlation was also shown with the four growth factors.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.147-155
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• 1999

The purpose of this study was to investigate the effect of phosphoric acid concentration on the movement of 2-hydroxyethylmethacrylate(HEMA) from bonding resin - resin composite combination through dentin in vitro. Freshly extracted human third molar teeth were divided into four groups each of 10 teeth. A closed chamber with 1 ml distilled water was attached to the CEJ of each tooth. An occlusal cavity of 4mm diameter & remaining dentin thickness of 1.0-1.5mm was prepared in each tooth. Dentin was treated with 10% phosphoric acid gel for 15 seconds. 32% phosphoric acid gel for 15 seconds, or with 35% phosphoric acid gel for 15 seconds. A control group not treated with acid gel was also prepared. The cavities were rinsed, dried and then treated with the HEMA-containing All-Bond 2 primer & bonding resin which was light-cured for 10 seconds. The cavities were then restored with Z100 composite resin(shade:A3.5:3M Dent. Prod. USA) & light cured for 30 seconds. Water samples were retrieved from the chambers over a time course (4.32, 14.4, 43.2, 144 & 432 minutes ; 1, 3 & 10 days) and analyzed by high performance liquid chromatography. The results were as follows. 1. HEMA was detected in the pulp chambers of all teeth from 4.32 minutes after resin placement The highest rate of release was in the first sample period (0-4.32 min) & rate of release declined exponentially thereafter. 2. No significant differences were found for mean release rate for HEMA over a time course among the four groups (p>0.05). 3. The diffusion rate was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phosphoric acid gel at the second sample period(4.32-14.4 min). 4. No significant differences were found for cumulative HEMA diffusion among the four groups at 10 days(p>0.05) and mean total(cumulative) release at 10 days for all groups was in the 9 - 16 nmol range. 5. The cumulative release was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phophoric acid gel at the third(14.4-43.2 min) & fourth(43.2-144 min) sample period.