• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.67-72
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• 1997

As a condition for obtaining the silk I type crystal that has stability and high reproducibility, after dissolving silk fibroin crystalline part (Fcp), the changes of recrystallized crystal structure according to dialytic pH were examined by x-ray diffraction and differential thermal analysis. The Fcp was obtained from the aqueous solution of silk fibroin enzymatic proteolyzed by chymotrypsin. The crystal structure of Fcp showed silk II type. When the Fcp was dissolved by 10M LiBr aqueous solution, the Fcp1 showed the silk II type at pH 9. However, besides the silk II type, the silk I type structure begins to appear at pH 8 and only the silk I type structure was found below pH 6. On the other hand, the Fcp2 that calcium chloride was used in the dissolution found only the silk I type crystal structure below pH8.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.27-44
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• 1994

The purpose of this study was to determine the effects of pH, temperature and time on the synthesis of hydroxyapatite(HAP) by spontaneous precipitation under relatively physiologic condition. Specimens were obtained from aqueous system with various pH, temperature and experimental time. Chemical composition, crystallographic structure and crystallinity of the synthetic HAP were evaluated by Infrared spectroscopy and powdered X-ray diffraction method. The following results were obtained. 1. No precipitate was obtained under pH 5.5. 2. All the specimens were concluded as HAP except one that was obtained under the condition of pH 6.5, $25^{\circ}C$ and 1 day. It was concluded as dicalcium phosphate dihydrate(DCPD). 3. The crystallinity of HAP was enhanced by increases in pH, temperature and time of the preparation. But, the crystallinity of the synthetic HAP was lower than that of the mineral HAP. 4. Intermediates such as DCPD and octacalcium phosphate were formed on the process of the synthesis of HAP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.856-862
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• 1994

In salt-preserved foods of every kinds, it was examined the growth condition of halophilic bacteria that induced a change of colour, taste, nutritive substance, a production condition of enzyme and a character of crude enzyme. Used bacteria is H. halobium a kind of extremely halophilic bacteria, and the required of optimum culture needed a quite long time of crude enzyme production is 168 hours. Optimum pH is about 7-7.5, so the traditional food of such neutrality pH as soybean paste and soy sauce particularly come into trouble because the growth can flourish in neutrality or alkaliescence, and the crude enzyme also appeared that best activation between pH 6 and pH 8. The optimum temperature is about 37$^{\circ}C$, the optimum temperature of enzyme is about 40 $^{\circ}C$ and the temperature stability is settled for 15 minutes and it is completely inactivated at 10 minutes. In the influence of each metal ion, Fe++ and Mn++ a stimulated the growth of H.halobium and the activation of enzyme, Cu++ and Zn++ were identified that made the growth and the activation of enzyme inhibit.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.619-623
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• 1989

The cultural condition of Pseudomonas mendocina for polysaccharide production was examined. The optimal medium contains following composition per liter of distilled water: Sucrose 23.75g, $(NH_4)_2SO_4$ 1.57g, Yeast extract 0.5g, $KH_2PO_4\;2.9g,\;MgSO_4.\;7H_2O\;1.0g,\;CaCO_3$ 2.5g. The optimum temperature and pH were $30^{\circ}C$ and 6.5. At the condition. Ps mendocina produced 5.98g/l of polysaccharide. The culture viscosity after 3 days was 191mPa.s at $70sec^{-1}$. The product yield $(Y_{p/s})$ and specific productivity $(Q_p)$ were 25.18% and 32.83mg/g-cell/h.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.243-248
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• 1996

To find out the oxidation process of potential acid sulfate soil(PASS) along with time. the PASS were treated with lime and ammonia water to adjust soil pH in laboratory column condition. pH range of PASS showed 6.5 to 7.5. however, complete oxidized PASS by $H_2O_2$ showed 2.1 to 2.5. After pilling the PASS under the natural condition. oxidation occured slowly from surface of the pilled soil. The oxidation of PASS proceeded slowly when the soil was in submerged condition. but quickly in dried condition. The content of sulfide-sulfur in PASS sharply decreased after exposing to the air and the decreasing rate was greater in dried than in submerged condition. The content of sulfate-sulfur continuously decreased in submerged condition. but increased in dried condition. Contents of $Fe^{+{+}}$ and $Al^{+{+}}$ in PASS were generally increased with time and the increasing rate was greater in submerged than in dried condition. Liming to PASS was slowly acting to pH change and ammonia water caused fast pH change within a short period of time. The contents of sulfate-sulfur and exchangeable aluminum in drainage water decreased with time and the contents of sulfide-sulfur and ferrous iron were increased.

• Food Engineering Progress
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• v.15 no.2
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• pp.143-147
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• 2011

For efficient extraction of protein from defatted rice bran, the 5 ranges of extraction pH (8, 9, 10, 11 and 12) and the 3 ranges of isoelectric precipitation pH (2, 4 and 6) were used. The protein content, browning reaction, the electrophoresis pattern and the recovery yield of soluble protein at each pH range were compared each other. The recovery yield of soluble protein increased in proportion to extraction pH, but at the same time, browning reaction became more conspicuous. The most amount of protein was recovered at the precipitation pH of 4. The SDS-PAGE patterns of the extracted proteins showed no significant correlations between pH and the protein content, but the highly alkaline condition was more advantageous to extract protein less than 35 kDa. In each pH range, the recovery yield of soluble protein averagely reached 32.5% on the basis of extraction. In result, it was found that combination of extraction pH 10 and precipitation pH 4, which resulted in 37.65% of recovery yield and low level of browning reaction, was the optimum condition for the extraction of protein from defatted rice bran.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.52-56
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• 2002

This study was conducted to evaluate the possibility of gamma radiation for reducing egg allergies through the observation of conformational and allergenic changes of egg ovomucoid (OM) in basic pH conditions. An OM solution of 2.0 mg/mL was individually prepared with different pH conditions, pH 7.0, 9.0 or 10.0, and was irradiated with the absorbed dose of 10 kGy. Irradiated OM solutions were tested by Ci-ELISA formatted with egg-hypersensitive patients'IgE. Binding abilities of IgE to OM in irradiated solution decreased with the increase of pH. Turbidity of the solution highly increased by irradiation and the increase of pH. A yellowish color was observed in the irradiated OM solution of basic condition. Coagulation of OM by irradiation decreased with the increase of pH, when observed by SDS-PAGE.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.359-367
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• 2003

Supplementary feeding strategies were evaluated from pre-calving throughout lactation on 24 dual-purpose Mpwapwa breed cows in their second or greater lactation, weighing 246-455 kg. The Mpwapwa breed is an established breed of 4 Bos indicus breeds and 8% of Bos taurus. The cows were penned and stall-fed individually. Eight weeks before calving to eight weeks after calving, the cows were divided into two groups and offered hay ad libitum with either 2 kg DM (L) or 4 kg DM/day (H) concentrates. Nine weeks after calving half of the cows on L-level continued with 2 kg DM/day (L-L) while the remainder received 4 kg DM concentrate daily (L-H). Half of the cows on H-group continued with 4 kg DM/day (H-H) while the remainder received 2 kg DM/day (H-L). The concentrate mixture comprised of sunflower seed cake (33%) and maize bran (67%). The cows consumed all the concentrate offered. Hay DM intake was similar (6.8 kg/day) and tended to decrease the last two weeks before calving increased again after calving. Live weight change and body condition score were similar across treatments before calving but differed after calving (p<0.05). Heavier cows with higher condition score pre-calving had a higher body weight loss and regained weight later. After treatment reallocation, live weight change and condition differed between treatments (p<0.05). Calves were allowed to suckle milk from one quarter. The amount of milk suckled and calf weight gains were not significantly different between treatments. The cows were removed from the experiment when the milk yield was below 4 kg per day. Cows on treatment H produced 6.2 kg and on treatment L 5.0 kg saleable milk/day (p<0.05) during the first 8 weeks post partum. During the period 9-18 weeks post partum the saleable daily milk on H-H, L-H, H-L and L-L were 5.2, 4.8, 4.7 and 4.3 kg, respectively (p>0.05).

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.525-528
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• 2001

The purpose of this study is to looking for the optimal condition of methane production enhancement. The conditions tested for increasing methane production were temperature. pH. and various carbon sources including methanol. formic acid. sodium acetate. succinic acid. and glucose. As a result, optimal temperature was 55 .C and optimal pH was around neutral condition. And methanol seemed to be best carbon source which can drastically increase methane production.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.22 no.4
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• pp.398-405
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• 2015

Purpose: This study was aimed to compare the effect between wet gauze with cold normal saline and wet gauze with cold water on thirst, oral cavity condition, and saliva pH among postoperative patients. Methods: This study was a quasi-experimental study with 56 participants. The experimental group received wet gauze with cold normal saline, and control group received wet gauze with cold water for three times at 15 minute intervals. Data were collected using visual analog scale for thirst, oral assessment guide for oral cavity condition and acidity tape for saliva pH. Measurement were made before applying the gauze and at 15min, 30min, and 45min after applying gauze. Data were analyzed using repeated measured ANOVA. Results: Thirst, oral cavity condition, and saliva pH improved in both groups with increasing number of gauze application. Thirst for the experimental group improved more than for the control group (F=4.29, p=.009), oral cavity condition except saliva, and saliva pH were not significantly different between the groups. Conclusion: This study results indicated that nurses can apply wet gauze with cold normal saline to reduce thirst and saliva acidity, and to improve the oral cavity condition for postoperative patients.