• Journal of Korean Biological Nursing Science
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• 제17권2호
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• pp.150-158
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• 2015

Purpose: This study aimed to evaluate the effects of gargling with S-solution and gargling with A-solution on salivary pH, coated tongue, and dental plaque index in preschool children. Methods: Non-equivalent control group pretest-posttest design was used to select the participants. 99 preschool children were divided into three groups. Dependent variables were recorded at baseline, 30 minutes, and 7 days after the first treatment was given. The data were analyzed using $X^2$-test, ANOVA, and repeated measures of ANOVA. Results: There were no significant differences in dependent variables in pre-test. However, the salivary pH in the S-solution group had significantly increased after 30 minutes (p<.05) and then again 7 days (p<.01) after the first treatment. Also, the S-solution and A-solution groups had greater decrease in dental plaque index after 30 minutes and again 7 days after the first treatment (p<.001) than the control group. With respect to coated tongue, there were no significant differences among the three groups. Conclusion: The results of this study indicate that essential oil gargling after brushing is helpful in improving oral health due to auxiliary oral hygiene effects with natural products. Specifically, gargling with S-solution is more effective than A-solution on oral health in preschool children by neutralizing salivary pH and reducing dental plaque index.

• 한국잠사곤충학회지
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• 제31권2호
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• pp.121-126
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• 1989

1. 제사용수의 pH가 총탄산이 낮은 용수에서는 견층 Sericin 용해에 미치는 영향이 적었지만, 총탄산이 높은 용수에서는 견층 Sericin 용해에 미치는 영향이 컸다. 2. 총탄산이 낮은 용수에서는 견층처리전후의 pH변화가 컸지만 총탄산이 높은 용수에서는 그 변화가 적었다. 3. 무탄산 증류수로 표준경도용액을 만들어 견층을 처리한 결과 경도가 높고 낮은데 대한 Sericin 용액관계는 없었다.

• 한국잠사곤충학회지
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• 제41권2호
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• pp.116-121
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• 1999

This study was aimed to explain the essence of Hydroxylammonium hydrochloride(H.A.) effect on degummed silk fiber increasing the colour sites due to oxime generating reaction. H.A. in aqueous solution caues to increase the amount of [H+] and reduce pH values as the concentration of H.A. increases. The rate of [H+] absorption of silk fiker in acidic solution differs on the basic of solution pH and shows a specific uptake in each pH, the lower the pH of solution, the higher the amount [H+] absorption. The pH of solution after treating of silk fiber in H.A. and HCl, showed more remaining [H+] in H.A. solution due to [H+] releasing under the procedure of oxime production. Also it was revealed that in higher concentration of H.A. the reaction for oxime fixation in silk fiber carried out stonger and as a result the bigger gap with acid uptake curve appeared. FT-IR analysis of silk fiber treated with H.A. revealed the creating of intermolecular H-bond at the 2,981-2.930 cm-1, which was not appeared for nontraeted silk fibers and shows H-bond between N-OH group in oue chain and C=) group in another chain of silk protein. Colourimetry of dyed silk fiber after H.A. tratment showed that the silk fiber treated with the high concentration of H.A. compare to low concentration, absorbed more dyeing molecules and so Showed less percontage of Whiteness.

• 마이크로전자및패키징학회지
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• 제27권3호
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• pp.29-34
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• 2020

본 연구에서는 무전해 니켈 도금액 pH 변화에 따른 electroless nickel immersion gold (ENIG)/Sn-3.0wt.%Ag-0.5wt.%Cu(SAC305) 솔더 접합부 취성 파괴 거동에 대하여 평가하였다. ENIG 표면처리를 위한 무전해 니켈 도금액의 pH는 4.0에서 5.5로 변화 시켰다. 무전해 니켈 도금 후 Ni-P 표면 관찰 결과, 도금액의 pH가 낮아질수록 Ni-P 층 nodule 표면에 핀홀이 증가하였다. 솔더링 후 접합부 계면에서는 (Cu,Ni)6Sn5 금속간화합물이 형성되었으며, 무전해 니켈 도금액의 pH가 증가할수록 솔더접합부의 계면 금속간화합물의 두께는 증가하였다. 고속전단 시험을 통하여 ENIG/SAC305 솔더 접합부의 취성파괴 거동을 확인하였으며, 무전해 니켈 도금액의 pH가 증가할수록 솔더접합부의 전단강도는 감소하는 경향을 보였다. 또한, 솔더 접합부의 취성 파괴율은 pH가 5일 때 가장 높은 값을 보였다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권2호
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• pp.215-223
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• 2017

The effects of acidic pH on several voltage-dependent ion channels, such as voltage-dependent $K^+$ and $Ca^{2+}$ channels, and hyperpolarization-gated and cyclic nucleotide-activated cation (HCN) channels, were examined using a whole-cell patch clamp technique on mechanically isolated rat mesencephalic trigeminal nucleus neurons. The application of a pH 6.5 solution had no effect on the peak amplitude of voltage-dependent $K^+$currents. A pH 6.0 solution slightly, but significantly inhibited the peak amplitude of voltage-dependent $K^+$ currents. The pH 6.0 also shifted both the current-voltage and conductance-voltage relationships to the depolarization range. The application of a pH 6.5 solution scarcely affected the peak amplitude of membrane currents mediated by HCN channels, which were profoundly inhibited by the general HCN channel blocker $Cs^+$ (1 mM). However, the pH 6.0 solution slightly, but significantly inhibited the peak amplitude of HCN-mediated currents. Although the pH 6.0 solution showed complex modulation of the current-voltage and conductance-voltage relationships, the midpoint voltages for the activation of HCN channels were not changed by acidic pH. On the other hand, voltage-dependent $Ca^{2+}$ channels were significantly inhibited by an acidic pH. The application of an acidic pH solution significantly shifted the current-voltage and conductance-voltage relationships to the depolarization range. The modulation of several voltage-dependent ion channels by an acidic pH might affect the excitability of mesencephalic trigeminal nucleus neurons, and thus physiological functions mediated by the mesencephalic trigeminal nucleus could be affected in acidic pH conditions.

• 대한화학회지
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• 제8권4호
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• pp.147-152
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• 1964

有機溶媒(benzene)에 의한 抽出法을 利用하고, 分光光度法에 의한 몰比法과 連續變化法을 써서, V(IV)-cupferrate와 V(V)-cupferrate의 化學沮成이 水溶液相에서 有機溶媒相으로 分配된 다음에도 雙하지 않을 것이라는 假定밑에서, 水溶液의 酸性度에 따르는 cupferrate 錯化合物의 化學組成을 決定하였다. V(IV)-cupferrate의 benzene 溶液에서의 最大吸光波長은 pH에 따라 445$m{\mu}$ 또는 450$m{\mu}$이고, V(V)-cupferrate의 그것은 pH 1.8以下에서는 pH에 無關하게 445$m{\mu}$이었다. V(V)-cupferrate의 化學組成은 沈澱이 形成되는 水溶液의 pH에 따라 다르며, pH 1.0 以下에서는 $VCupf_4$, pH 1.3∼1.7에서는 $HVOCupf_3$ 또는 $VCupf_4$와 $VOCupf_2$의 거의 같은 몰씩으로된 混合物이고, pH 1.8∼4.3에서는 $VOCupf_2$이었다. V(V)-cupferrate의 化學組成은 水溶液의 pH에 따라 變化가 없고, pH 1.8 以下에서는 $HVO_2Cupf_2$이었다.

• 패션비즈니스
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• 제22권1호
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• pp.124-134
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• 2018

This study examined the dyeing characteristics and spectrum of cotton and silk by using dyeing solution extracted from aronia. The value $L^{\ast}$ which indicates the brightness of cotton regardless of mordant increases with increasing pH from pH 3.5 to pH 10.5. The color difference value(${\Delta}E$) of the cotton was generally high in pH 3.5 regardless of mordant existence. The silk showed the highest ${\Delta}E$ value in pH 3.5 dye solution as cotton did. On the other hand, the silk with mordant dyed showed the highest ${\Delta}E$ value in pH 7. Silk fabrics dyed with Aronia solution turns out red in pH 3.5, blue in pH 7 and yellow in pH 10.5. This is because of the amino acid, one of the silk ingredients, combines with a part of anthocyanin to show blue. As the result of the spectrum measurement, the maximum absorption wavelength of Aronia solution was increased in the order of pH 10.5, pH 3.5 and pH 7, regardless of extraction temperature and mordant. The measurement results of color fastness to washing and color fastness to light are generally low. Therefore, there is a need for further study to improve color fatness in the future.

• Nuclear Engineering and Technology
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• 제45권1호
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• pp.107-114
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• 2013

It is required that the pH of the sump solution should be above 7.0 to retain iodine in a liquid phase and be within the material compatibility constraints under LOCA condition of PWR. The pH of the sump solution can be determined by conventional chemical equilibrium constants or by the minimization of Gibbs free energy. The latter method developed as a computer code called SOLGASMIX-PV is more convenient than the former since various chemical components can be easily treated under LOCA conditions. In this study, SOLGASMIX-PV code was modified to accommodate the acidic and basic materials produced by radiolysis reactions and to calculate the pH of the sump solution. When the computed pH was compared with measured by the ORNL experiment to verify the reliability of the modified code, the error between two values was within 0.3 pH. Finally, two cases of calculation were performed for the SKN 3&4 and UCN 1&2. As results, pH of the sump solution for the SKN 3&4 was between 7.02 and 7.45, and for the UCN 1&2 plant between 8.07 and 9.41. Furthermore, it was found that the radiolysis reactions have insignificant effects on pH because the relative concentrations of HCl, $HNO_3$, and Cs are very low.

• 한국세라믹학회지
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• 제25권2호
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• pp.136-142
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• 1988

β-Al2O3, which is used for solid electrolyte membrances in sodium-sulfur batteries, was prepared by sol-gel process. Sodium-n-propoxide NaOC3H7 and aluminum-isopropoxide Al(OC3H7)3 were hydrolyzated in the solution at pH 3, pH 7, pH 9 and pH 11, respectively. The sol-gel processed samples were calcined at several temperature steps, respectively and analysed by thermal analyser(DT-TGA), infrared spectrum analyser and X-ray diffraction analyser. The gelling rate of solution at pH 7 was much higher than that of the solution at pH 3. Thermal exchanging behavior of the gels at pH 3 were similar to Na2O·Al2O3·6H2O and, above pH 7, were similar to Na2O·Al2O3·3H2O. When samples' composition ratio was 9.13 : 90.87 [NaOC3H7:Al(OC3H7)3] at pH 7, β-Al2O3 was formed at 1100℃.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1997년도 하계 학술대회 논문집
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• pp.89-98
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• 1997

This study was conducted to develop an automatic nutrient-solution control system for small-scale growers. The nutrient-solution control system consisted of a low-cost and precise metering device and a personal computer. The system controlled electric conductivity(EC) and pH of nutrient-solution based on the time-based feedback control method with the information about temperature, EC, and pH of the nutrient-soIution. The performance of the nutrient-solution control system was evaluated through the control of EC and pH while compared with those of commercial nutrient-solution control system. Also an experimental cultivation of tomato was conducted to verify and to improve the developed system. Results of this study were as follows. 1. An automatic nutrient-solution control system based on a low-cost and precise metering device was developed. 2. The developed system controlled EC and pH within $\pm$0.05 mS/cm and $\pm$0.2 pH full scale error respectively at $24^{/circ}C$. 3. When using the commercial system, the controlled values of EC and pH of the 500l of water were 1.29 mS/cm and 6.1 pH for the setting points of 1.4 mS/cm and 6.0 pH respectively at $22^{/circ}C$. 4. The developed nutrient-solution control system showed $\pm$0.05 mS/cm of deviation from the setting EC value over the experimental cultivation period. 5. The deviation from the average values of Ca and Mg mass content in the several nutrient-solution were 0.5% and 1.8% respectively.