• 한국콘크리트학회:학술대회논문집
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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.

• Korean Chemical Engineering Research
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• 제57권1호
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• pp.133-141
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• 2019

침전법으로 환류방법 또는 수열합성법을 이용하여 산 염기점을 갖는 고비표면적 지르코니아를 합성하였다. 제조된 지르코니아는 침전제로 수산화암모늄 수용액을 사용하여 Zr 용액의 pH를 2에서 10 범위 내에서 조절하였으며 질소흡착분석, X-선 회절분석(XRD), 이소프로판올 승온탈착법(IPA-TPD), 주사전자현미경 분석, X-선 광전자분광분석, 산-염기점 분석을 통해 IPA 분해반응의 촉매활성과 연관하여 특성분석을 수행하였다. 환류방법을 사용할 시, tetragonal 상이 높은 지르코니아를 얻기 위해서는 Zr 용액의 pH가 높아야 하며, pH 9 이상에서는 순수한 tetragonal 상의 지르코니아 합성이 가능하였다. 또한, 비표면적이 큰 지르코니아를 얻기 위해서는 높은 pH가 요구되었으며, pH 10에서 합성한 경우에는 $600^{\circ}C$에서 소성 후에도 $260m^2g^{-1}$의 높은 비표면적이 얻어졌다. 하지만 같은 조건 하에서 고압이 수반되는 수열합성에는 $40m^2g^{-1}$ 이하의 매우 낮은 비표면적을 보였으며, monoclinic 상의 지르코니아가 합성되었다. 고 비표면적 tetragonal 상의 지르코니아를 얻기 위해서는 용액의 pH가 가장 큰 영향을 미쳤으며, 용액의 pH와 무관하게 높은 압력이 필요한 수열합성에서는 monoclinic 지르코니아가 생성되었으며 상대적으로 비표면적이 낮게 나타났다. 높은 비표면적과 tetragonal 상을 갖는 지르코니아는 염기점에 비해 산점이 우세하여 IPA 분해반응에서 선택적 탈수반응만 진행되는 프로필렌만 생성되었다.

• 상하수도학회지
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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.

• 한국식품과학회지
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• 제37권5호
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• pp.806-811
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• 2005

본 실험은 녹차된장이 고지방식이를 급여한 흰쥐의 체중변화 및 혈청 지단백질 등에 미치는 영향을 연구하고자 기본식이 (basal diet)를 급여한 B군과 0.5% 콜레스테롤과 15% 라드를 첨가한 고지방식이를 급여한 H군, 고지방식이와 20% 일반된장을 첨가한 식이를 급여한 H-S군, 고지방식이에 녹차된장을 첨가한 식이를 급여한 H-0.6GS군(0.6% 녹차 추출물)과 H-4GS(4% 녹차가구)군을 10주간 사육한 후 다음과 같은 결과를 얻었다. 1. 체중 증가량은 고지방식이군인 H군이 가장 높았으며, 녹차된장군인 H-4GS군이 일반된장군보다 체중증가가 적은 것으로 나타났다(p<0.05). 식이 효율(FER)이나 식이 섭취량은 군간에 유의적인 차이가 없었다. 간의 무게는 고 지방식이군인 H군이 일반된장군(H-S군)과 녹차된장군(H-GS군)보다 높았으며 (p<0.05), 실험군 중에서 H-4GS군의 간의 무게가 가장 낮았다. 2. 혈청 포도당(glucose), 요산(uric acid), 빌리루빈(bilirubin), 총단백질(total protein)의 농도는 각 군 간의 차이가 없었다. 혈중 GOT, GPT, BUN의 농도는 녹차된장군이 일반된장군이나 고지방군에 비해 낮았고, 일반된장군과 녹차된장군간의 차이는 유의적이었다(p<0.05). 3. 일반된장군과 녹차된장군의 경우 모두 콜레스테롤의 농도가 고지방식이군보다 낮았고(p<0.05), 중성지방의 농도는 녹차된장섭취군이 일반된장군보다 낮았으며(p<0.05), 녹차된장군간의 차이도 있었다(p<0.05). RFI(risk factor index)는 녹차된장군이 가장 낮게 나타났고, 녹차된장군, 일반된장군, 고지방식이군 간의 차이는 유의적이었다(p<0.05).

• 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.

• KSBB Journal
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• 제19권3호
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• pp.221-225
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• 2004

Bacillus sp. 유래의 Bacillus polyfermenticus SCD를 Bisroo $t^{ⓡ}$라고 부르고, 이것은 생균제로서 산업적으로 매우 유용하다. 본 연구에서는 B. polyfermenticus SCD를 산업적으로 활용성을 증대시키기 위해 three layer coating법을 사용하여 인공위액의 pH 변화에 대한 안정성과 열안정성, glucose 농도에 따른 안정성을 연구하였다. 그 결과 코팅한 B. polyfermenticus SCD가 인공위액에 대한 내성에서는 배양 4시간을 기준으로 pH 2는 30%, pH 4는 20%, pH 6은 14% 상승효과가 있었음을 알 수 있었고, 온도변화에 대한 안정성에서는 코팅한 B. polyfermenticus SCD가 8$0^{\circ}C$에서 2시간 기준으로 안정성이 약 40% 증진됨을 확인할 수 있었다. 고농도 (30%)의 glucose에서 코팅한 B. polyfermenticus SCD는 안정하였으며, 코팅하지 않은 것보다 약 50% 안정성이 증대됨을 확인할 수 있었다. 그리고 pH 4.0에서는 코팅한 B. polyfermenticus SCD는 코팅을 하지 않은 B polyfermenticus SCD보다 전체적으로 생존율이 40% 이상, pH 6.0에서는 생존율이 42% 이상 증진됨을 알 수 있었다.

• 상하수도학회지
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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.

• 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.

• 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.

• 대한물리치료과학회지
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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.