• Title/Summary/Keyword: pH dependent

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A study on the relationship between concentration of phosphorus, turbidity, and pH in water and soil (물과 토양에서 인의 농도, 탁도 그리고 pH와의 관계에 관한 연구)

  • Min, Young-Hong;Hyun, Dae-Yoeung;Eum, Chul-Hun;Lee, Seung-Ho
    • Analytical Science and Technology
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    • v.24 no.4
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    • pp.304-309
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    • 2011
  • In this research, behaviour of turbidity and phosphorus in water and soil dependent upon pH and a change of water was studied. Phosphorus dissolve rate from turbidity was increased for water if potential of hydrogen was less than pH 4 or more than pH 7. Turbidity release rate from soil was increased with pH. Turbidity release rate from soil was drastically increased for water if potential of hydrogen was more than pH 4. turbidity release rate from soil was stabilized more than pH 6. Dissolved phosphorus was increased from 2 hours to 24 hours and stabilized in 24 hours. Turbidity was reached the peak of 24 hours and decreased from 24 hours to 96 hours. Turbidity and dissolved phosphorus was decreased for water if these samples were changed a overlying water. Behaviour of turbidity was analogous to dissolved phosphorus when potential of hydrogen was increased from pH 6 to pH 10 and a change of overlying water was increased from 1 time to 4 times. These results suggest that phosphorus dissolve rate and turbidity were directiy correlated with pH. These results are of great importance in lakes because most lakes have a pH in the range of pH 7-10.

Structural Performance of H-shaped Column-Rafter Connection in the P.E.B Systematic Steel Frames (P.E.B 시스템 강골조에서 H형강 기둥 - Rafter 접합부의 구조성능)

  • Kim, Jong Sung
    • Journal of Korean Society of Steel Construction
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    • v.17 no.3 s.76
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    • pp.347-356
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    • 2005
  • Recently, pre-engineering building (P.E.B.) systematic frames are increasingly being used in steel factory buildings, but almost of the related techniques are dependent on the engineering program (e.g, MBS, LTI), which is usually imported from other countries. These are designed under the AISC-ASD because at present there is no Korean design code for P.E.B. frames. Also, there are few studies onbehaviour and we need to develop the element techniques by using H-shaped components.In particular, there is a tendency towards overestimated design because column-rafter connections have been designed with extended end plate type joint, which is treated asrigid joint,so structural examinations are needed. Therefore, this study represents a basic step in ascertaining the application of P.E.B. systematic frames by using H-shaped column-rafter connectionwith flush type end plate. Its structural performance is compared with that of existing extended type joint using a structural performance test. The structural behaviour of specimen was understood qualitatively and the possibility of application (e.g, design aid charts) of semi-connection (flush type) with H-shaped column-rafter was determined.

The Influence of H+ and Cl- Ions on the Corrosion Inhibitive Effect of Poly(para-aminophenol) for Iron in Hydrochloric acid

  • Manivel, P.
    • Corrosion Science and Technology
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    • v.16 no.4
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    • pp.187-193
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    • 2017
  • Polymer amines are found to show distinct corrosion inhibition effects in acidic media. The functional groups of organic compounds have a wide role in the physical and chemical properties, for the inhibition efficiency with respect to steric factors, aromaticity, and electron density. The influence of $H^+$ ions and $Cl^-$ ions on the corrosion inhibitive effect of poly(p-aminophenol) for iron in hydrochloric acid was studied using electrochemical methods such as impedance, linear polarization, and Tafel polarization techniques. The experiments were conducted with and without the inhibitor, poly(p-aminophenol). The concentration range of $H^+$ ions and $Cl^-$ ions are from 1 M to 0.05 M and 1 M to 0.1 M, respectively. With the inhibitor poly(p-aminophenol), this study shows that inhibition efficiency decreases with the reduction of $H^+$ ion and $Cl^-$ ion concentrations in aqueous solution. Further, it reveals that the adsorption of an inhibitor on the surface of iron is dependent on the concentrations of $H^+$ and $Cl^-$ ions in the solution and the adsorption of inhibitor on the iron surface through the cationic form of amine.

The Change of Cell-cycle Related Proteins and Tumor Suppressive Effect in Non-small Cell Lung Cancer Cell Line after Transfection of p16(MTS1) Gene (폐암세포에 p16 (MTS1) 유전자 주입후 암생성능의 변화 및 세포주기관련 단백질의 변동에 관한 연구)

  • Kim, Young-Whan;Kim, Jae-Yeol;Yoo, Chul-Gyu;Han, Sung-Koo;Shim, Young-Soo;Lee, Kye-Young
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.796-805
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    • 1997
  • Background : It is clear that deregulation of cell cycle progression is a hallmark of neoplastic transformation and genes involved in the $G_1$/S transition of the cell cycle are especially frequent targets for mutations in human cancers, including lung cancer. p16 gene product, one of the G1 cell-cycle related proteins, that is recently identified plays an important role in the negative regulation of the the kinase activity of the cyclin dependent kinase (cdk) enzymes. Therefore p16 gene is known to be an important tumor suppressor gene and is also called MTS1 (multiple tumor suppressor 1). No more oncogenes have been reported to be frequently related to multiple different malignancies than the alterations of p16 gene. Especially when it comes to non-small cell lung cancer, there was no expression of p16 in more than 70% of cell lines examined. And also it is speculated that p16 gene could exert a key role in the development of non-small cell lung cancer. This study was designed to evaluate whether p16 gene could be used as a candidate for gene therapy of non-small cell lung cancer. Methods : After the extraction of total RNA from normal fibroblast cell line and subsequent reverse transcriptase reaction and polymerase chain reaction, the amplified p16 cDNA was subcloned into eukaryotic expression plasmid vector, pRC-CMV. The constructed pRC-CMV-p16 was transfected into the NCI-H441 NSCLC cell line using lipofectin. The changes of G1 cell-cycle related proteins were investigated with Western blot analysis and immunoprecipitation after extraction of proteins from cell lysates and tumor suppressive effect was observed by clonogenic assay. Results : (1) p16(-) NCI-H441 cell line transfected with pRC-CMV-p16 showed the formation of p16 : cdk 4 complex and decreased phosphorylated Rb protein, while control cell line did not. (2) Clonogenic assay demonstrated that the number of colony formation was markedly decreased in p16(-) NCI-H441 cell line transfected with pRC-CMV-p16 than the control cell line. Conclusion : It is confirmed that the expression of p16 protein in p16 absent NSCLC cell line with the gene transfection leads to p16 : cdk4 complex formation, subsequent decrease of phosphorylated pRb protein and ultimately tumor suppressive effects. And also it provides the foundation for the application of p16 gene as a important candidate for the gene therapy of NSCLC.

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Temperature and pH-Responsive Release Behavior of PVA/PAAc/PNIPAAm/MWCNTs Nanocomposite Hydrogels

  • Jung, Gowun;Yun, Jumi;Kim, Hyung-Il
    • Carbon letters
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    • v.13 no.3
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    • pp.173-177
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    • 2012
  • A drug delivery system (DDS) was prepared with a temperature and pH-responsive hydrogel. Poly(vinyl alcohol) (PVA)/poly(acrylic acid) (PAAc)/poly(N-isopropylacrylamide) (PNIPAAm)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared by radical polymerization for the temperature and pH-responsive hydrogels. MWCNTs were employed to improve both the thermal conductivity and mechanical properties of the PVA/PAAc/PNIPAAm/MWCNT nanocomposite hydrogels. Various amounts of MWCNTs (0, 0.5, 1 and 3 wt%) were added to the nanocomposite hydrogels. PVA/PAAc/PNIPAAm/MWCNT nanocomposite hydrogels were characterized with a scanning electron microscope. The mechanical properties were measured with a universal testing machine. Swelling and releasing properties of nanocomposite hydrogels were investigated at various temperatures and pHs. Temperature and pH-responsive release behavior was found to be dependent on the content of MWCNTs in nanocomposite hydrogels.

Indole Derivatives I, The Kinetics and Mechanism of the Nucleopilic Addition of Thiourea to 1-Benzylindole-3-Acetophenone (인돌유도체 I, 1-Benzylindole-3-acetophenone유도체에 대한 Thiourea의 친핵성 첨가반응 메카니즘과 그 반응속도론적 연구)

  • Lee, Ki-Chang;Hwang, Sung-Kwu;Ryu, Jung-Wook;Hwang, Young-Hyun;Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.8 no.2
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    • pp.175-181
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    • 1991
  • The kinetics of the addition of 1-benzylindole-3-(p-substituted) acetophenone derivatives was investigated by ultraviolet spectrophotometery in 30% dioxane -$H_2O\;at\;25^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The Substituent effects on 1-benzylindole-3-(p-substituted) acetophenone derivatives were studied, and addition were facilitated by electron attracting groups. On the base of the rate equation, substituent effect, and general base effect the plausible addition mechanism was proposed : Below pH 3.0, only neutral thiourea molecule was added to the carbon-carbon double bond, and in the range of pH 0.0${\sim}$14.0, netural thiourea molecule and thiourea anion competitively attacted the double bond. By contrast, above pH 10.0, the reaction was dependent upon only the addition of thiourea anion.

Mitogen-activated protein kinase signaling pathway mediates 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced apoptosis in Jurkat T cells.

  • Kwon, Myung-Ja;Jeong, Kyu-Shik;Choi, Eun-Jeong;Lee, Byung-Ho
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.75.3-76
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    • 2003
  • The present study was performed to examine mitogen-activated protein kinase associated pathways in mediation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced cell apoptosis in cultured Jurkat T cells. TCDD significantly decreased cell viability in a concentration-dependent manner (p<0.05 at 10-300 nM). TCDD (10 nM) also time-dependently decreased cell viability (p<0.05 at 12-48 h). c-Jun NH$_2$-terminal kinase was significantly phosphorylated with TCDD treatment in a time dependent manner. (omitted)

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Nodulation and Growth of Trifolium subterraneum Cultivars as Affected by pH (Subterranean Clover 의 근류형성(根瘤形成)과 생장(生長)에 대한 pH의 영향(影響))

  • Kim, Moo-Key
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.2
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    • pp.138-145
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    • 1989
  • Little information is available on the effects of low pH on nodulation and growth of subterranean clover cultivars. Plants of 11 cultivars were inoculated with an acid-tolerant strain of Rhizobium trifolii and grown for 28 days in continuously flowing nitrogen-free nutrient solutions maintained at six constant pH values from 4.0 to 6.5. At pH 4.0, 4 cultivars failed to nodulate and the remainder formed only a few nodules; nodulation was delayed by 2 to 3 days in this treatment. All cultivars nodulated at pH 4.5 but, with the exception of cv. Dwalganup, nodule numbers were significantly less than at $pH{\geq}5.0$. Only in cvv. Clare and Woogenellup were nodule numbers significantly greater at pH 6.5 than at 5.0. Whole plant dry matter yields were strongly depressed at pH 4.0(21 to 33% of maximum). At pH 4.5, relative yields of all cultivars except Dwalganup were significantly depressed without significant reductions in nodule dry weights, suggesting that nodule function was inhibited by acidity. These results are consistent with the view that nodulation and growth of plants dependent on symbiotic nitrogen fixation are much more sensitive to low pH per se than is host plant growth in the presence of adequate mineral nitrogen.

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Quantitative Evaluation of Skin Condition According to Ayurvedic Constitution Classification (아유르베다 체질에 따른 피부 유형 분석)

  • Choi, Eun-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.9
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    • pp.3375-3379
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    • 2010
  • Objective: The purpose of this study was to investigate the characteristics of facial skin parameters (hydration, lipid and pH) on forehead and cheek according to Ayurvedic constitution classification of Vata, Pitta and Kapha. The condition of hydration, lipid and pH in the facial skin was measured using non-invasive diagnostic technique. The collected data was analyzed with the SPSS 16.0 windows statistical program. Design: Eighty-nine Korean female subjects were recruited for this study and the average age of them was $19.9{\pm}0.84$ years. Three groups by the Ayurvedic constitution were classified by questionnaire. Results: There was a significant difference in hydration, lipid and pH according to Ayurvedic constitution. The measurement of hydration on the face depending on the constitution were shown in the order of Pitta, Kapha and Vata (p<0.001). The measurement of lipid on the face depending on the constitution were shown in the order of Kapha, Pitta and Vata (p<0.001, p<0.01). The measurement of pH on the face depending on the constitution were shown in the order of Kapha, Pitta and Vata (p<0.01). Conclusion: Facial skin surface seemed to be dependent on Ayurvedic constitution classification in Korean. These findings indicated that Ayurvedic constitution classification might be a useful esthetic treatment for caring facial skin in the future.

Changes of the Antioxidant Enzymes and Histopathological Changes of Liver and Kidney According to the Administered Dosage of Bambusae Caulis in Liquamen in Mice (죽력 (Bambusae Caulis in Liquamen)의 투여량에 따른 생쥐의 항산화효소 활성과 간과 신장의 조직병리학적 변화)

  • Kim, Jeong-Sang
    • Applied Microscopy
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    • v.32 no.4
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    • pp.399-410
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    • 2002
  • This study was performed to investigate the effects of Bambusae Caulis in Liquamen (bamboo extract) on the changes of antioxidant enzymes and histopathological changes of liver and kidney in mice when administered in different dosages. The experimental groups were divided into four. For control group, 0.9% NaCl (0.2 ml/25 g B.W.) and for experimental groups, 5% (H1 group), 10% (H2 group), and 20%(H3 group) bamboo extract diluted with 0.9% NaCl, were administered (0.2 ml/25 g B.W.) respectively for 28 days at an interval of 48 hours. MnSOD activities were increased in H1 group (46%, P<0.05), H2 group (40%, P<0.05), and H3 group (34%, P<0.05) as compared to the control group. CuZnSOD activities were increased in H1 group (11%, P<0.05), but were decreased in H3 group (13%, P<0.05). The activities of catalase were decreased in H1 group (39%, P<0.05), H2 group (34%, P<0.05), and H3 group (31%, P<0.05) as compared to the control group. Histopathological observation revealed ballooned hepatocytes in the pericentral and periportal veins of H1 group. More ballooned and injured hepatocytes than in H1 group were observed in the H2 and H3 groups. Detachment of endothelial cells of the central vein was observed in the H2 and H3 groups. These results indicated that bamboo extract developed dose-dependent changes in antioxidant enzyme activities and developed histopathological changes of liver and kidney.