• 제목/요약/키워드: high pH

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pH Reduction of High Porous Concrete to Grow Plants (식생을 위한 다공성 콘크리트의 pH 저감에 대한 실험적 연구)

  • 박찬규;정재홍;김한준
    • Proceedings of the Korea Concrete Institute Conference
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.1129-1134
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    • 2001
  • In the point of the Eco-concrete(Environmentally Friendly Concrete), it is very important to reduce the pH of high porous concrete by the pH to be able to grow plants, because the pH of concrete is l1~13. But the method of measuring the pH of high porous concrete is not well-defined, yet. Therefore, first, this paper report the method of measuring the pH of high porous concrete. Secondly this paper reports the pH reduction of high porous concrete to grow plants.

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Synthesis and Characterization of High Surface Area of Zirconia: Effect of pH (고비표면적 지르코니움 산화물의 제조 및 특성 분석: pH 영향)

  • Jeong, Ye-Seul;Shin, Chae-Ho
    • Korean Chemical Engineering Research
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    • 제57권1호
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    • pp.133-141
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    • 2019
  • High specific surface area zirconia with acid-basic property was synthesized by precipitation using reflux method or hydrothermal synthesis method using ammonium hydroxide solution as precipitant in the range of pH of Zr solution from 2 to 10. The prepared zirconia was characterized by the nitrogen adsorption, X-ray diffraction (XRD), isopropanol temperature programmed desorption (IPA-TPD), scanning electron microscopy and X-ray photoelectron spectroscopy, and the catalytic activity in the IPA decomposition reaction was correlated with the acid-basic properties. When using reflux method, high pH of Zr solution was required to obtain high fraction of tetragonal zirconia, and pure tetragonal zirconia was possible at pH 9 or higher. High pH was required to obtain high specific surface area zirconia, and the hydrous zirconia synthesized at pH 10 had high specific surface area zirconia of $260m^2g^{-1}$ even after calcination at $600^{\circ}C$. However, hydrothermal synthesis with high pressure under the same conditions resulted in very low specific surface area below $40m^2g^{-1}$ and monoclinic phase zirconia was synthesized. High pH of the solution was required to obtain high specific surface area tetragonal phase zirconia. In hydrothermal synthesis requiring high pressure, monoclinic zirconia was produced irrespective of the pH of the solution, and the specific surface area was relatively low. Zirconia with high specific surface area and tetragonal phase was predominantly acidic compared to basicity and only propylene, which was observed as selective dehydration reaction in IPA decomposition reaction, was produced.

The Effects of pH and Dosages According to Qualities of Raw Waters and Basicity of Coagulants (원수 수질특성과 응집제 염기도에 따른 응집 pH 및 주입량의 영향)

  • Park, Noh-Back;Lee, Bum;Tian, Dong-Jie;Lee, Young-Ju;Jun, Hang-Bae
    • Journal of Korean Society of Water and Wastewater
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    • 제24권5호
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    • pp.581-593
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    • 2010
  • The objectives of this study were to investigate the effects of raw water pH and basicity of coagulants on turbidity removal with several raw waters having different level of turbidity, alkalinity and pH. Raw waters were sampled from M, S and B water treatment plants(WTP) located at Miryang, Nakdong, Han river, respectively. Six coagulants which have different levels of basicity and aluminum contents were used for this evaluation. High basicity of the coagulant helped to properly control coagulation processes for treating turbid and low alkali raw water. It was difficult for operators to determine optimum coagulant dose for high basicity coagulants, since residual turbidity tended to decrease continuously as coagulant dose increased. Turbidity removal efficiencies with high basicity coagulants(E and F) were higher than the other coagulants at ambient pH for the M WTP. Turbidity removal efficiencies, however, at adjusted pH 7.0 showed similar among six coagulants. Residual turbidity kept low at excess dosages with high basicity coagulants. Optimum coagulant dosages at adjusted pH 7.0 showed higher than those at ambient pH in M WTP. On the contrary in B WTP, optimum coagulant dosage at ambient pH were higher than that at adjusted pH 7.0.

Effects of Green Tea-Soybean Paste on Weights and Serum Lipid Profiles in Rats Fed High Fat Diet (녹차 된장이 고지방식이를 급여한 흰쥐의 체중 및 혈청 지질성분에 미치는 영향)

  • Park, Jin-Hee;Ha, Ae-Wha;Cho, Jung-Soon
    • Korean Journal of Food Science and Technology
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    • 제37권5호
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    • pp.806-811
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    • 2005
  • Effects of green tea-soybean paste on weight-changes and serum lipid profiles in rats fed high fat diet were investigated. Sprague-Barley male rats divided into five groups were fed five different diets for 10 weeks: B group, basal diet H group, high fat-diet containing 0.5% cholesterol+15% lard H-S group, high fat diet containing soybean paste H-0.6GS group, high fat diet containing 0.6% green tea-soybean paste H-4GS group, high fat diet containing 4% green tea-soybean paste. H group showed highest weight gain (p<0.05). Addition of green-tea soybean paste to high-fat diet significantly decreased weight gain, H-4GS group showing highest weight loss (p<0.05). No significant differences in food efficiency ratio and total food intake were found among groups. Liver weight of H group was highest. Addition of green tea-soybean paste to high fat diet significantly reduced liver weight (p<0.05, Table 2). Concentrations of glucose, uric acid, bilirubin, and total protein were similar among all group. Mean GPT values of H-4GS group were significantly different from these of H- and H-S groups (p<0.05). H-S, H-0.6GS, and H-4GS groups had significantly lower triglyceride and total cholesterol, and higher HDL than H-group (p<0,05). H-4GS group had significantly lower serum triglyceride than H-0.6GS group (p<0.05).

Surface pH Of The Northeastern Pacific Ocean

  • Park, Kilho
    • 한국해양학회지
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    • 제1권1_2호
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    • pp.1-6
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    • 1966
  • A latitudinal, differential pH distribution is observed in the Northeastern Pacific Ocean with a pH range of 8.15 at high latitude (42 N) to 8.29 at low latitude (23 N). These pH values are generally greater than the calculated equilibrium pH with respect to atmospheric carbon dioxide. If we assume that the calculated equilibrium pH values ae valid, then the surface waters are undersaturated with respect to the atmospheric carbon dioxide during April to June 1966. A high surface pH value of about 8.26 was observed immediately south of the SubarcticBoundary zone near 170 W. This value differs from the equilibration pH by as much as 0.1 unit.

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Increased Stability of Bacillus polyfermenticus SCD in Low pH, High Temperature and High Glucose Concentration via Three Layer Coating (Bacillus polyfermenticus SCD의 Three Layer Coating에 의한 pH, 열, 높은 glucose 농도에 대한 안정성효과)

  • 이진옥;전경동;강재선;이재화
    • KSBB Journal
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    • 제19권3호
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    • pp.221-225
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    • 2004
  • Bacillus polyfermenticus SCD derived from Bacillus sp., which is commonly called as Bisroot$^{ⓡ}$. The goal of this study, is to Increase stability of Bacillus polyfermenticus SCD in low pH, high temperature and high glucose concentration via three layer coating. The viability of coated Bacillus polyfermenticus SCD increased to 30%, 20%, 14% in the condition of pH 2 4 6 than that of uncoated Bacillus polyfermenticus SCD at 37$^{\circ}C$ for 4 h. Final viability of the coated Bacillus polyfermenticus SCD in 80$^{\circ}C$ increased to 40% than that of uncoated Bacillus polyfermenticus SCD. In high glucose concentration coated Bacillus polyfermenticus SCD is more stable than uncoated about 50%. In conclusion, the three layer coated Bacillus polyfermenticus SCD is very stable for low pH, high temperature and high glucose concentration.

Improvement of Water Treatment Efficiency by Poly Aluminum Chloride Overdosing in High pH Raw Water (폴리염화알루미늄 과량주입에 의한 고(高) pH 원수의 수처리효율 개선)

  • Lim, Jaecheol;Kim, Jinkeun
    • Journal of Korean Society of Water and Wastewater
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    • 제23권1호
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    • pp.39-46
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    • 2009
  • A method to improve water treatment efficiency by coagulant overdosing for high pH raw water at a drinking water treatment plant (WTP) which had no pH adjusting facilities was investigated. Poly aluminum chloride (PACl) was used for coagulant, and turbidity removal efficiency was evaluated as a function of PACl dosage increases. pH and turbidity of supernatant of jar-tester were 7.10 and 0.50 NTU respectively, when the turbidity, pH, alkalinity, water temperature, conductivity of raw water were 1.75 NTU, 9.38, 46.5 mg/L, $6.4^{\circ}C$, $400{\mu}s/cm$, respectively. Turbidity of settled water was reduced from 2.18 NTU to 0.28 NTU (87% reduction) when PACl dosage was increased from 16 mg/L to 45 mg/L at a full scale WTP. This can be attributed to the recovery of coagulant efficiency by pH reduction with the increase of coagulant dose, however coagulation efficiency was reduced with the formation of Al(OH)4- by PACl addition at higher pH. Coagulant overdosing was proven to be a rapid and effective method for high pH raw water, which can be applied at drinking WTP.

Effects of Ultra-high Pressure Homogenization on the Emulsifying Properties of Whey Protein Isolates under Various pH

  • Lee, Sang-Ho;Subirade, Muriel;Paquin, Paul
    • Food Science and Biotechnology
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    • 제17권2호
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    • pp.324-329
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    • 2008
  • The effect of ultra-high pressure homogenization on the emulsifying properties of whey protein was investigated in a model emulsion made with whey protein isolate and soya oil under various pH. The emulsifying properties, the average diameter of the oil droplets ($d_{vs}$), and the protein load, were measured for each emulsion produced at different homogenization pressures (50 to 200 MPa) and pH values (4.6 to 8.0). According to the results of variance analysis and response surface, the pH had more influence on oil droplet size and protein load than homogenization pressure. The model equations, which were obtained by response surface analysis, show that pH and homogenization pressure had the major effect on oil droplet size and protein load. Higher homogenization pressure decreased the average droplet size and the protein load. Homogenization at high pressure, as opposed to low pressure, causes no overprocessing, but the effect was pH-dependent. The average diameter of the oil droplets increased slightly by decreasing the pH from 8.0 to 6.5 and then increased dramatically toward the isoelectric point of whey protein (i.e., at pH 4.6). Moreover associated droplets were found at acidic pH and their size was increased at high temperature.

Analysis of the Structure and Stability of Erythropoietin by pH and Temperature Changes using Various LC/MS

  • Chang, Seong-Hun;Kim, Hyun-Jung;Kim, Chan-Wha
    • Bulletin of the Korean Chemical Society
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    • 제34권9호
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    • pp.2663-2670
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    • 2013
  • The purpose of stability testing is to provide evidence about how the quality of a drug varies with time under the influence of a variety of environmental factors. In this study, erythropoietin (EPO) was analyzed under different pH (pH 3 and pH 9) and temperature ($25^{\circ}C$ and $40^{\circ}C$) conditions according to current Good Manufacturing Practice (cGMP) and International Conference on Harmonisation (ICH) guidelines. The molecular weight difference between intact EPO and deglycosylated EPO was determined by SDS-PAGE, and aggregated forms of EPO under thermal stress and high-pH conditions were investigated by size exclusion chromatography. High pH and high temperature induced increases in dimer and high molecular weight aggregate forms of EPO. UPLC-ESI-TOF-MS was applied to analyze the changed modification sites on EPO. Further, normal-phase high-performance liquid chromatography was performed to identify proposed glycan structures and high pH anion exchange chromatography was carried out to investigate any change in carbohydrate composition. The results demonstrated that there were no changes in modification sites or the glycan structure under severe conditions; however, the number of dimers and aggregates increased at $40^{\circ}C$ and pH 9, respectively.

An in Vivo Study of High Voltage Pulsed Current on pH in the Healing Wound Bed

  • Song, Byung-H.
    • Journal of Korean Physical Therapy Science
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    • 제6권4호
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    • pp.173-178
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    • 1999
  • The purpose of this study was to determine the effect of High Voltage Pulsed Current on pH in the healing wound bed. Seven adults, four males and three females, were studied with a total of fifty-five viable treatment sessions. Using a Cardy Digital pH meter, we measured the pH in the wound bed following saline rinse both prior to treatment and after a forty-five minute treatment. Analysis of all viable records(n=54) did not show a significant change in pH(p=0.82). The mean pH change in NoN-Smokers(-0.14) was more acidic when compared to the mean pH change in smokers(0.27) which was more alkaline.

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