• 한국토양비료학회지
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• 제42권5호
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• pp.336-340
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• 2009

최근 급속한 산업화가 진행되고 있는 중국의 편서풍 영향 하에 위치한 우리나라의 경우에는 장거리 이동에 따른 강우의 산성도 변화 및 예상되는 피해에 대한 대책 마련을 위하여 강우의 화학성에 대한 지속적인 모니터링이 필요하다. 태안지역 강우의 화학적 특성을 알아보기 위하여 2007년 4월부터 10월까지 19점의 빗물을 채수하여 pH 및 화학적 성분조성을 조사하였다. 강우량을 고려한 가중평균(volume-weighted mean) 이온농도 변화와 알카리성 물질들에 의한 빗물의 산성도 중화를 평가한 결과는 다음과 같다. 조사기간 중 평균 pH값은 4.9를 보였다. 빗물의 EC는 조사기간 평균 $32.9{\mu}S\;cm^{-1}$을 나타냈으며, 월별로는 9월에 $9.7{\mu}S\;cm^{-1}$로 조사기간 중 가장 낮은 값을 보였으며, 강우량이 가장 적었던 4월에 $91.4{\mu}S\;cm^{-1}$의 높은 수치를 나타내어 강우량 분포에 따른 EC의 계절적 특성을 보였다. 빗물의 조성에서 양이온 구성은 $Na^+$> $NH_4{^+}$ > $Ca^{2+}$ > $H^+$ > $Mg^{2+}$ > $K^+$의 순이었으며, $Na^+$와 $NH_4{^+}$가 전체 양이온 함량의 70% 이상을 차지하였다. 음이온은 $SO_4{^{2-}}$ > $NO_3{^-}$ > $Cl^{-}$ 순으로 $SO_4{^{2-}}$가 약 56%를 차지하였다. Sulfate의 조사기간 중 평균 함량은 $152.1{\mu}eq\;L^{-1}$ 이었다. 총 sulfate 함량 중 비해염 sulfate $(nss-SO_4)^-$ 함량은 평균 90%로 빗물 중에 함유된 sulfate의 대부분이 인위적인 발생원에서 기인되었다. 또한, 강우 산성도의 중화 정도를 알아보기 위하여 평가한 fractional acidity (pAi) 및 theoretical acidity ($pH_{the}$.) pH를 비교한 결과 1:1 직선의 오른쪽으로 분포되어 있음에 따라 본 조사기간 강우의 산성도가 빗물에 포함된 각종 알카리 물질들에 의해 중화되었음을 보였다.

• 한국식품저장유통학회지
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• 제14권6호
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• pp.578-583
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• 2007

고 이산화탄소 전처리가 토마토의 숙성 중 품질 변화에 미치는 영향을 구명하기 위해 breaker와 pink 단계에 토마토를 수확한 후 고 이산화탄소(25, 50 및 100%)를 24시간 처리한 후 상온에서 숙성시키면서 품질변화를 조사하였다. 이산화탄소 전처리시 숙성기간 중 과피 변색과 과실의 연화가 억제되는 효과가 극명하였으며 이러한 효과는 pink 단계의 토마토 보다는 breaker 단계의 토마토에서 더 컸다. 이산화탄소 처리가 토마토의 숙성 중 당도에 미치는 영향은 없었으며, 100% 농도 처리시 breaker 토마토의 산도가 낮아지는 경향을 보였다. 관능검사를 실시한 결과 breaker 토마토의 경우 고 이산화탄소 처리에 의해 단맛이 감소하였다. 토마토의 산미와 조직감은 과실의 숙도에 관계없이 이산화탄소 처리에 의해 높게 유지되었다. Breaker 단계에서 수확한 토마토는 이산화탄소 전처리에 의한 이취 발생이 없으나, pink 토마토에서는 이취가 발생하여 향에 대한 선호도가 낮아졌다. 상온에서 22일 후 고 이산화탄소 장해 증상이 관찰되었는데, breaker 토마토는 50% 이상의 농도에서, pink 토마토의 경우 25% 이상의 농도 처리시 발생하였다.

• 한국조리학회지
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• 제15권4호
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• pp.47-55
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• 2009

고추장에 기능성 식품인 석류 농축액을 첨가한 고추장 소스 제품을 개발하여 석류를 활용한 다양한 식품 개발을 모색하고자 석류 과즙 농축액을 5, 10, 15, 20%로 첨가하여 제조한 고추장 소스의 품질 특성인 일반성분, 점도, pH, 산도, 당도, 당산비, 색도 및 관능검사를 실시하였다. 수분함량과 조회분은 석류 과즙 농축액 첨가량이 증가할수록 유의적으로 감소하였으며, 탄수화물, 단백질, 지방은 첨가량이 증가할수록 유의적으로 증가하였다. 점도와 pH는 첨가량이 증가할수록 유의적으로 감소하였고, 산도와 당도는 첨가량이 증가할수록 유의적으로 증가하였다. 당산비는 석류 과즙 농축액 첨가량이 증가할수록 유의적으로 감소하였다. 명도 L값과 b값은 석류 과즙 농축액 첨가량이 증가할수록 유의적으로 감소하였으며, a값은 대조군보다 석류 과즙 농축액 첨가군들이 유의적으로 낮았다. 색도, 향미, 점도 및 종합적인 기호도는 대조군이 가장 낮았고, 석류 과즙 농축액 첨가량이 증가할수록 유의적으로 증가하다가 20%를 첨가한 시료에서 감소하였다. 신맛, 아린맛, 쓴맛, 떫은 맛 및 이취는 석류 과즙 농축액 첨가량이 증가할수록 유의적으로 증가하였다. 따라서 점도, pH, 산도, 당도, 색도, 기호도 등의 품질 특성을 고려해 보면, 15% 첨가는 석류 과즙 농축액의 생리 기능성을 고려할 때 고추장 소스의 품질 특성에 좋은 영향을 미칠 수 있을 것으로 생각되었다.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.433-442
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• 1998

The purpose of this study was to observe the changes of acidity of resin cement(Time Line), glass ionomer cement(GC Fugi Lining LC), zinc phosphate cement(Fleck's zinc cement). zinc oxide eugenol cement(Sultan,Chemists.) in vivo and in vitro. Class I cavities with 3mm depth were prepared on the occlusal surfaces of 20 recently extracted human Mn. molar teeth and 20 human Mn. 3rd molar teeth in oral cavity. The prepared cavities were divided into 4 groups of each 5 teeth using the above 4 cavity liners. Each cement was mixed in accordance with manufacturer's direction at the room temperature of $23^{\circ}{\pm}5^{\circ}C$ and filled into the cavity in a width of 1 mm. The microelectrode of pH meter was inserted into the prepared cavity which was filled with mixed cement, and the acidity of cement was measured for 3 days from the beginning of cement mix in vitro and in vivo. The measured acidity was then statistically analyzed by ANOVA. The results were as follows. 1. In vitro, the pH of zinc oxide eugenol cement was statistically lower than that of the three other groups at 2min, 4min, 6min, 8min, 10min, 12min, 18min, 20min. (p<0.05). 2. The pH of zinc oxide eugenol cement in vivo was statistically higher than that in vitro at 16min,16min, 20min(p<0.05). 3. The pH of zinc phosphate cement in vivo was statistically higher than that in vitro at 4min, 20min(p<0.05). 4. In vitro and in vivo, there was no significant difference in the pH between the resin cement and the glass ionomer cement(p>0.05). 5. The initial acidity was not high, but almost neutral in all kinds of the cements.

• 한국작물학회지
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• 제36권3호
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• pp.266-270
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• 1991

미곡의 장기보관에서 보관면적과 소요비용을 절약하려면 정조보관보다 현미 또는 백미로 보관하는 것이 용이하다. 그러나 미곡의 고미화와 식미 악화가 우려되어 본 연구에서는 20개월간 정부창고에서 보관된 벼품종들을 정조, 현미, 백미로 가공하고 각각 지대, PP대, PE대에 포장하여 수확 후 32개월째에 발아력, 지방산도, 식미를 검정하였다. 1. 발아율은 장기 보관함에 따라 감소하였고 밀양 2003보다 추청의 감소가 심하였다. 가공상태에 따라 현미로 제현하여 보관하면 발아율 감소가 현저하였고 포장재질에 따른 차이는 없었다. TTC검정도 유사한 경향을 보여 발아력의 간접검정법으로 이용될 수 있었다. 2. 지방산도는 정조<백미<현미 순으로 높아졌고 포장재료에 따라서는 PP대<지대<PE대 순으로 증가되었다. 특히 현미 보관은 지방산도가 KOH 30mg 이상에 달하여 고미화 특성을 보였고 이를 방지하려면 정조를 지대 또는 PP대에 보관하거나 백미는 지대, PP대, PE대에 보관하여 도 무난하였다. 3. 저장미곡의 식미는 도정보관에 따라 악화되었고 특히 현미보관에서 백미보관 보다 불량하였는데 호분층에 포함된 지방의 산패 때문이었다. 또 품종별로 지방산도가 증가함에 따라 식미는 불량하여 졌다.

• Journal of Astronomy and Space Sciences
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• 제31권4호
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• pp.325-333
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• 2014

We are motivated by both the accumulating evidence for the connection of solar variability to the chemistry of nitrogen oxide in the atmosphere and recent finding that the Galactic cosmic-ray (GCR) influx is associated with the solar north-south asymmetry. We have analyzed the measured pH in precipitation over the 109 stations distributed in the United States. We have found that data of pH in precipitation as a whole appear to be marginally anti-correlated with the solar asymmetry. That is, rain seems to become less acidic when the southern hemisphere of the Sun is more active. The acidity of rain is also found to be correlated with the atmospheric temperature, while not to be correlated with solar activity itself. We have carried on the analysis with two subsamples in which stations located in the east and in the west. We find that the pH data derived from the eastern stations which are possibly polluted by sulfur oxides and nitrogen oxides are not correlated with the solar asymmetry, but with the temperature. On the contrary, the pH data obtained from the western stations are found to be marginally anti-correlated with the solar asymmetry. In addition, the pH data obtained from the western stations are found to be correlated with the solar UV radiation. We conclude by briefly pointing out that a role of the solar asymmetry in the process of acidification of rain is to be further examined particularly when the level of pollution by sulfur oxides and nitrogen oxides is low.

• 대한한방종양학회지
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• 제4권1호
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• pp.1-16
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• 1998

In order to investigate the effect of Bujaleejungtang, by means of oral medication to rats and mice, to isolated intestine and stomach, and the effect to pyloric ulcer, indomethacin-induced ulcer, secretion of gastric juice, and to transport ability of intestine content were studied as the action to G-I tract. The effect to normal rats and resperpine-treated rats were studied as the action to thermo-regulation. The results were as follows: 1. Bujaleejungtang showed the inhibitory effect on the smooth muscle contraction induced by acethylcholine chloride and barium chloride in the isolated mice ileum. 2. Bujaleejungtang showed inhibitory effect on the contraction induced by acetylcholine chloride and barium chloride in the rat fundus-strip. 3. Inhibitory effect of Bujaleejungtang on pyloric ulcer, indomethacin-induced gastric ulcer in rats was statistical recognized(p<0.05). 4. No inhibitory effect of Bujaleejungtang on gastric juice secretion in Shay rats was recognized. 5. Inhibitory effect of Bujaleejungtang on gastric free acidity and total acidity in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg) (p<0.001). 6. Inhibitory effect of Bujaleejungtang on pepsin output in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.001). 7. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the small intestine of mice was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05). 8. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the large intestine of mice was recognized(p<0.05). 9. Inhibitory effect of Bujaleejungtang on rectal temperature in normal rats was recognized. 10. Inhibitory effect of Bujaleejungtang on rectal temperature in reserpine-treated rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05).

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1265-1272
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• 2007

A solid acid catalyst, NiSO4/CeO2-ZrO2 was prepared simply by promoting ZrO2 with CeO2 and supporting nickel sulfate on CeO2-ZrO2. The support of NiSO4 on ZrO2 shifted the phase transition of ZrO2 from amorphous to tetragonal to higher temperatures because of the interaction between NiSO4 and ZrO2. The surface area of 10-NiSO4/1-CeO2-ZrO2 promoted with CeO2 and calcined at 600 oC was very high (83 m2/g) compared to that of unpromoted 10-NiSO4/ZrO2 (45 m2/g). This high surface area of 10-NiSO4/1-CeO2-ZrO2 was due to the promoting effect of CeO2 which makes zirconia a stable tetragonal phase as confirmed by XRD. The role of CeO2 was to form a thermally stable solid solution with zirconia and consequently to give high surface area and acidity of the sample, and high thermal stability of the surface sulfate species. 10-NiSO4/1- CeO2-ZrO2 containing 1 mol% CeO2 and 10 wt% NiSO4, and calcined at 600 oC exhibited maximum catalytic activities for both reactions, 2-propanol dehydration and cumene dealkylation.

• Food Science and Biotechnology
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• 제14권4호
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• pp.509-513
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• 2005

The purpose of this study was to develop a new preparation process of ginseng extract using high concentrations of ginsenoside $Rg_3$, a special component in red ginseng. From when the ginseng saponin glycosides transformed into the prosapogenins chemically, they were analyzed using the HPLC method. The ginseng and ginseng extract were processed with several treatment conditions of an edible brewing vinegar. The results indicated that ginsenoside $Rg_3$ quantities increased over 4% at the pH 2-4 level of vinegar treatment. This occurred at temperatures above $R90^{\circ}C$, but not occurred at other pH and temperature condition. In addition, the ginseng and ginseng extract were processed with the twice-brewed vinegar (about 14% acidity). This produced about 1.5 times more ginsenoside $Rg_3$ than those processed with regular amounts of brewing vinegar (about 7% acidity) and persimmon vinegar (about 3% acidity). Though the white ginseng extract was processed with the brewing vinegar over four hr, there was no change for ginsenoside $Rg_3$. However, the VG8-7 was the highest amount of ginsenoside $Rg_3$ (4.71%) in the white ginseng extract, which was processed with the twice-brewed vinegar for nine hr. These results indicate that ginseng treated with vinegar had 10 times the quantity of ginsenoside $Rg_3$, compared to the amount of ginsenoside $Rg_3$ in the generally commercial red ginseng, while ginsenoside $Rg_3$ was not found in raw and white ginseng.

• 동아시아식생활학회지
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• 제22권5호
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• pp.613-623
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• 2012

In this study, the quality characteristics of salad dressing prepared with mulberry, Schisandra chinensis, and Discorea powder were evaluated. Salad dressing was prepared with salad base (plain yogurt : mayonnaise : fresh cream = 8:1:1), mulberry, Schisandra chinensis for acidity, and Discorea powder for viscosity (4:4:6:1 or 4:4:6:3). Discorea powder was added at levels of 0, 7, and 18% to the salad dressing. As the concentration of Discorea powder increased, the pH level increased, and acidity decreased. Hunter's color L (lightness) value of salad dressing decreased as the amount of Discorea powder increased. Viscosity increased according to the amount of Discorea powder. Moreover, total phenolic content increased according to the amount of Discorea powder. Further, DPPH antioxidant and hydroxyl radical activity of mulberry salad dressing increased as the amount of Discorea powder increased. Sensory preference test results showed that the salad dressing added with Discorea powder had higher scores for color, flavor, taste, and texture than the control. Regarding overall preference, salad dressing containing 7% Discorea powder had the highest scores among the treatments. From these results, salad dressing containing mulberry, Schisandra chinensis for acidity, and Discorea powder for viscosity could be a functional salad dressing with high antioxidant activity.