• Journal of Korean Society of Environmental Engineers
• /
• v.32 no.5
• /
• pp.461-468
• /
• 2010

This study investigated variation of rainwater quality by seasonal and storage duration of rainwater in Changwon city. Seasonally, the pollutants concentration of rainwater were higher in spring and winter. In the case of rainwater and storage rainwater quality, pH of rainwater was 4.3, storage rainwaters were 6.0 and Turbidity increased about 8 times from 1.82 NTU to 14.61 NTU. The changes of storage water quality during the storage period, initial KMnO4 consumption rainwater was exceeded drinking water standard. Total solid in rainwater was detected as 116 mg/L, it tended to stable at around 70∼80mg/L after storage period for a 6day.

• Korean Journal of Plant Resources
• /
• v.10 no.4
• /
• pp.305-313
• /
• 1997

The effect of acid rain on plant isozyme response was studied with the treatment of simulated acid rain to Pinus densiflora, P. nigida and P. koraiensis for 9 months. The isozyme pattern of $\alpha$-Esterase($\alpha$-Est), Peroxidase(POD) and Glutamate dehydrogenase(GDH) were observed in the control (pH 5.6) and simulated acid rain (pH 3.5) treatment. No changes of isozyme pattern in $\alpha$-Est was observed in P. densiflora after 9 month treatment of simulated acid rain, but, two new isozymes were activated in P. nigida in the same treatment. In P. koraiensis, two new isozyme were activated but five isozymes were not activated. P. densiflora did not show any difference in POD and GDH after the treatment of simulated acid rain. P. nigida showed activation of eight and two isozymes in POD and GDH, respectively. P. koraiensis showed inactivation of 4 isozymes in POD but showed no changes In GDH.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.1
• /
• pp.77-85
• /
• 1995

To develop a simple test for evaluation crop tolerance to acid rain disks of recently matured leaves of 12 crops（rice, corn, barley, wheat, soybean, adzuki bean, Chinese cabbage, radish, lettuce, spinach, and tomato） were soaked in simulated acid rain（SAR） solutions for 1, 2, 3, and 4 hours. Changes in pH and electrical conductivity（EC） of leaf soaked solutions and changes in the color of the soaked leaves were observed. The pH and EC of leaf soaked solutions differed depending on the pH of SAR, crops, and soaking time. Among the crops differences in pH of leaf soaked solutions were most stable and significant for 1∼4 hour soaking in pH 4.0 SAR solution, but those of EC were for 1∼4 hour solaking in pH 5.0 SAR soultions. Color of leaves soaked in pH 2.0 SAR solutions was changed significantly, but not in the pH 3.0 or higher SAR solutions. Vis-ual damages of intact leaves caused by spray of pH 2.0 SAR solution in the greenhouse was posi-tively correlated with pH changes in pH 4.0 SAR solution, but not with EC changes in pH 5.0 SAR solution or color changes of leaves soaked in pH 2.0 soulution. The pH of solution was posi-tively correlated with Ca and Mg concentrations of the solutions and EC was positively correlated with K, Ca, and Mg.

• Applied Biological Chemistry
• /
• v.41 no.5
• /
• pp.337-341
• /
• 1998

The morphological and cultural characteristics of alkalophilic Coryneform bacteria TU-19 were investigated at various pHs. This bacterium showed normal growth pattern at $pH\;9.0{\sim}10.0$, but the cell growth was completely inhibited at extreme pH (12.0 or more). Interestingly, at pH 8.0 the morphology of the bacterial cells seems to form convoluted filaments during the exponential growth phase while at pH 10.0, the optimal pH for the growth of this organism, the bacteria grew with variable paired or single forms, and straight rods during growth stages. Growing in alkaline media $(pH\;9.0{\sim}11.0)$, it adjusted the pH of the culture media to around pH 8.5 by itself.

• Applied Biological Chemistry
• /
• v.21 no.2
• /
• pp.109-111
• /
• 1978

This study was undertaken in order to observe the differences of the changes in the water-holding capacity (WHC), extractability of proteins (EP) and pH value of ovine muscle during storage. WHC decreased gradually after slaughter, reached to minimum at about 2-4hr after death as well as that of pH value and then these were recovered along with the progress of the storage. The same tendency was observed in EP but the degree of the changes in pH value up to 6hr after slaughter was more rapid this that of WHC and EP. After the fourth day, the rate of recovery in WHC, EP and pH value in ovine muscle during storage showed similar pattern.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05b
• /
• pp.808-813
• /
• 1998

EDTA 의 농도 및 온도가 일정한 조건에서 수용액의 pH 를 변화시켜 가며, 토양으로부터 Co$^2$$^{+}$ 이온의 탈착특성을 살펴보았다. 실험범위에서, pH 4 일 때 $CO_2$$^{+}$ 이온의 탈착율이 가장 양호하였으며, pH 가 상승함에 따라 탈착율이 감소되는 것으로 나타났다. 또한, 반응중 철 성분이 용해되어 나오는데 이는 반응 초기 수소이온에 의한 용해와 반응중 탈착된 Co$^2$$^{+}$ 이온에 의한 용해로 설명하였다.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2008.04a
• /
• pp.106-123
• /
• 2008

재생 신문지 생산공정의 탈묵처리는 공정의 pH에 따라 그 수율이 달라진다. 기존의 알칼리 탈묵처리 조건으로부터 의사 중성 혹은 중성으로 pH가 중화됨에 따라 과도한 탈묵 리젝트가 발생하고 수율이 저하되는 문제점이 있다. 본 연구에서는 탈묵 pH에 따른 수율 변화를 실험실 평가를 바탕으로 분석하고 리젝트를 절감하는 방안을 탐색하여 수율을 최적화하고자 하였다.

• Food Science and Preservation
• /
• v.24 no.6
• /
• pp.827-833
• /
• 2017

This study was investigated the effects of various commercial sanitizers on microbial characteristics in fresh-cut iceberg lettuce during storage. For screening sanitizer, lettuce was cut and dipped in chlorine water ($0.2ml{\cdot}L^{-1}$), solution of organic acids such as ascorbic acid, citric acid, acetic acid, mixture of ascorbic acid and acetic acid (1-6%), and solutions of commercial sanitizers such as Formula 4$^{TM}$ (1,3,4%), Fresh produce wash$^{TM}$ (1,3,4%), Cleancol$^{TM}$ (1%), Chitochol$^{TM}$ (1%) and Natural Ca$^{TM}$ (0.1%) for 3 min, respectively. Washing lettuce with selected sanitizers resulted in reduction of aerobic bacteria of more than 2 log CFU/g. Initial pH of lettuce was related with the pH of sanitizers. pH ranged from 4.7 to 6.1 in Formula 4 (4%, pH 1.7) and Natural Ca (0.1%, pH 12.0), respectively. Chlorine water showed consistent and significant inhibition effect in all of microorganisms except total coliform. Over 3% of Formula 4 and Fresh produce wash were found to have high bactericidal activity among sanitizers. The sanitizers of chlorine water, Fresh produce wash, Chitochol and Natural Ca were effective in reducing yeast and mould populations. As coliform and E. coli, Formula 4 (4%) showed the highest bactericidal activity. The bactericidal effect of commercial sanitizers during storage varied with the kinds and concentrations of tested sanitizers. Although inhibition effect was not showed during storage, these results suggest that commercial sanitizers could be an alternative to chlorine for washing fresh-cut produce.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.2
• /
• pp.195-198
• /
• 1989

The water binding capacity (WBC) of hoe plasma protein was investigated. The centrifugal condition for optimal separation of plasma from hog blood was fixed at 1400 g-force. The WBC of 5%-plasma-protein-solution eel increased rapidly between pH 6 and 7 but gradually after pH 7 at $85^{\circ}C$ for 30 min. The higher heating temperature demonstrated the higher WBC of 5%-plasma-protein-solution gel at pH 7 within short period of time. The WBC of 5%-plasma-protein-solution gel increased rapidly at the beginning of heating. The WBC per gram of plasma protein at pH 7 and $85^{\circ}C$ for 30 min decreased as protein concentration of the plasma solution increased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.3
• /
• pp.380-383
• /
• 2000

국내에서 생산되는 농산물 통조림 중 황도, 백도, 파인애플, 밀감, 포도, 후르츠칵테일, 김치 통조림을 선택하여 실온에서 1년 동안 저장하면서 3개월 간격으로 개봉하여 pH를 비롯하여 주석, 납 함량을 조사하여 다음과 같은 결과를 얻었다. pH는 김치통조림을 제외한 모든 통조림에 서 저장기간의 증가에 따른 변화가 거의 없었다. 통조림 검사항목 중 중금속에 해당하는 납과 주석의 경우 저장기간 증가에 따라 함량이 증가하였으며, pH가 비교적 낮은 통조림의 경우 그 용출정도가 다소 높았으며 pH가 4이상인 김치 통조림에서는 타 시료에 비해 주석 함량이 비교적 낮았다. 저장기간이 12개월 경과 후에도 납, 주석함량은 모두 기준치에 비해 상당히 낮아 식품으로서 안전한 것으로 생각된다.