• 한국대기환경학회지
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• 제10권2호
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• pp.98-104
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• 1994

Precipitation samples were collected at Kosan, Cheju Island over a period of 6 months An automatic rain sampler was manufactured domestically and installed at Kosan station. All samples were collected on a weekly basis. Samples were analyzed for S $O_4$$^{=}$, N $O_3$$^{[-10]}$ , C $l^{[-10]}$ , N $H_4$$^{+}$, N $a^{+}$, $K^{+}$, $Ca^{++}$, $Mg^{++}$, and pH and specific conductivity. The quality analysis of rain sample data were performed based on ion balance and specific conductivity. The pH of rain samples ranged between 4.6 to 6.6. Bicarbonate ion concentration were included in ion balance and specific conductivity calculations. The sum of cation concentrations were slightly greater than the sum of anion concentrations. Calculated specific conductivity was greater than measured specific conductivity. The most probable explanations for this discrepancy is "an anion too low or anion missing." Two criteria were used to identify outliners. They are 1) the difference between the sum of anion concentrations and cation concentration is more than 50 $\mu$eq./1 and 2) the difference between calculated and measured specific conductivity is more than 25%. Chemical analysis from several samples did not satisfy these quality control criteria. Volume weighted average concentrations were calculated. Dominant free acids in rain samples were N $a^{+}$, C $l^{[-10]}$ , S $O_4$$^{=}$, N $O_3$$^{[-10]}$ ions in order of abundance. Non-seasalt sulfate comprises 76% of total sulfate.sulfate.e.ate.e.

• Asian-Australasian Journal of Animal Sciences
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• 제33권6호
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• pp.941-948
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• 2020

Objective: This study was carried out to determine the effects of elevated dietary cation and anion difference (DCAD) on dry matter intake (DMI) and ruminal fermentation pattern in lactating dairy goats under tropical conditions. Methods: Ten dairy goats were divided into two groups of five animals each. The groups received diets at different DCAD levels, either a control diet (22.81 mEq/100 g dry matter [DM], DCAD-23) or a DCAD-39 diet (39.08 mEq/100 g DM, DCAD-39). After parturition, DMI and water intake were recorded daily. Ruminal fluid and urine were collected, and nutrient digestibility measurements were carried out at 8th weeks postpartum (PP-8). Blood samples were collected at PP-4 and PP-8 to measure plasma leptin. Results: Dry matter intake/body weight (DMI/BW) at PP-8 of the animals fed the DCAD-39 diet was significantly higher than those fed with DCAD-23 diet (p<0.05). Animals fed with DCAD-39 consumed more water than those fed DCAD-23 over 24 h, particularly at night (p<0.05). Ruminal pH, acetate concentration, and urinary allantoin excretion increased with the DCAD-39 diet, whereas ruminal butyrate concentration was lower with the DCAD-39 diet. On the other hand, other ruminal parameters, such as total volatile fatty acid concentration, propionate molar proportion and acetate/propionate average ratio, were not affected by increased DCAD supplementation. Apparent digestibility was improved by increased DCAD supplementation. Plasma leptin concentration was higher with DCAD supplementation. Conclusion: When feeding goats with DCAD-39 under tropical conditions, an increase in DMI was associated with improved apparent digestibility of nutrients, ruminal fermentation and microbial protein synthesis. An increase in plasma leptin concentration could not explain the effect of high DCAD on DMI.

• 한국대기환경학회지
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• 제20권5호
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• pp.593-601
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• 2004

In this study, we are going to compare the chemical composition of the precipitation that falls in the Dangjin and Anmyon-do areas by analyzing the water soluble components (anion and cation). We also examined the effects of seasonal change and regional difference in those data sets. The [$NO_3\;^- \;+\;SO_4\;^{2-}$] at 49.2${\mu}$eq/l is 67% of the total anion of 73.1${\mu}$eq/l, while that of [$NH_4\;^+\;+\;Ca^{2+}$] at 37.7${\mu}$eq/l is 62% of the cation in Dangjin area. Also, the [$NO_3\;^-\;+\;SO_4\;^{2-}$] concentration of 151.8 (${\mu}$eq/l) is 62% for the total anion of 143.5 (${\mu}$eq/l), and the [$NH_4\;^+\;+\;Ca^{2+}$] concentration of 119.7 (${\mu}$eq/l) is 47% for the cation of 254.3 (${\mu}$eq/l) in Anmyon-do area. The ion composition ratio is shown for the order by 22% of $SO_4\;^{2-}$, 20.8% of $NH_4\;^+$ and 15.4% of $Cl^-$ that is the sum of 58.7% for the total ion composition in Dangjin area, and is the order by 33.8% of $NH_4\;^+$, 16.3% of $SO_4\;^{2-}$ and 11.1% of $Cl^-$ in Anmyon-do area. Furthermore, We predicted that even areas which were previously clean will get acid rain if there is large scale construction there or nearby.

• 한국환경과학회지
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• 제18권6호
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• pp.595-601
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• 2009

The effects of the cation-to-anion resin ratio and bed depth on ion exchange performance of mixed-bed were studied at ultralow solution concentration. Breakthrough curves were experimentally obtained for NaCI solution as functions of resin ratio and bed depth. The bed depth affects the pattern of the sodium breakthrough curve but not the chloride breakthrough curve in beds because of the selectivity difference. Resin selectivity determines the shape of breakthrough curves, Some sodium and chloride breakthrough curves crossed at a point as a function of resin ratio. The lower cation-to-anion resin ratio showed the higher effluent concentration or treated volume of the crossover point regardless of the total resin weight.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1713-1720
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• 2007

Influence of -110, +110, +220 and +330 mEq/kg of dry matter (DM) dietary cation-anion difference (DCAD) on growth performance of Thalli lambs were examined in a randomized complete block design. Four DCAD diets were randomly allotted to four groups, with ten lambs in each group. A linear increase in nutrient intake was recorded with increasing DCAD level. The digestibilities of nutrients were higher in lambs fed -110 DCAD diet than those fed +110, +220 and +330 DCAD diets. Lambs fed +330 DCAD diet had higher nitrogen balance than those fed -110 and +110 DCAD diets. Blood pH and serum $HCO_3$ increased with increasing DCAD level. Serum chloride was higher in lambs fed -110 DCAD diet, while serum (Na+K)-(Cl+S) increased linearly with increasing DCAD level. Serum calcium increased with decreasing DCAD level while serum magnesium and phosphorus remained unaffected. Lambs fed -110 DCAD diet had higher Ca balance than those fed +110, +220 and +330 DCAD diets. Urine pH increased with increasing DCAD level. Lambs fed +220 and +330 DCAD diets gained more weight than those fed -110 and +110 DCAD diets. In conclusion, increased DCAD level not only increased the dry matter intake but also improved the weight gain of growing Thalli lambs.

• 한국자연치유학회지
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• 제7권1호
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• pp.10-19
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• 2018

본 연구는 제주의 휴양림 지역을 중심으로 16개 지점을 정해서 일간 별에 따른 대기질 중의 음이온과 양이온수를 측정하여 그 분포와 변이에 대한 연구가 목적이었다. 측정 평균수의 범위는 제일 낮은 제주시 4449.35 ions/cm³, 제일 높은 천지연폭포는 3471.25 ions/cm³ 의 범주로 나타났다. 순서로 보면, 제일 낮은 제주시< 함덕 < 1100 m < 농장 < 교래A < 사려니 < 절물 < 교래B < 거문오름 < 제주시< 한라 숲길 < 한라산 수목원 < 성판악 < 동백산 < 정방 < 원양< 천지연 순이었다. 고도순으로 측정치의 음이온 본 연구는 제주의 휴양림 지역을 중심으로 16개 지점을 정해서 일간 별에 따른 대기질 중의 음이온과 양이온수를 측정하여 그 분포와 변이에 대한 연구가 목적이었다. 측정 평균수의 범위는 제일 낮은 제주시 4449.35 ions/cm³, 제일 높은 천지연폭포는 3471.25 ions/cm³의 범주로 나타났다. 순서로 보면, 제일 낮은 제주시< 함덕 < 1100 m < 농장 < 교래A < 사려니 < 절물 < 교래B < 거문오름 < 제주시< 한라 숲길 < 한라산 수목원 < 성판악 < 동백산 < 정방 < 원양 < 천지연 순이었다. 고도순으로 측정치의 음이온수치 함량의 차이를 일정하게 차이를 보이지는 않았으나, 통계적으로는 유의한 차이(p<.001)가 있었다. 양이온 평균수가 낮은 천지연폭포는 90 ions/cm³, 제일 높게 나타난 한라산 수목원의 수는 729.8 ions/cm³이었으며, 그 차이는 729.8 ions/cm³로 높게 나타났다. 높은 순서로 보면 제일 낮은 천지연 < 1100 m < 동백산 < 제주시 < 사려니 < 원양 < 성판악 < 함덕 < 정방 < 교래B < 절물 < 농장 < 교래A < 한라산 숲길 < 거문오름 < 한라수목원 순으로 측정되었다. 음양이온 모두 지형적으로 낮은 지대와 높은 지역은 함량이 낮게 측정되었다. 음이온과 양이온 및 고도의 분산분석에서 측정지역 간의 함량차이는 모두 유의성이 있었고, 또한 음이온과 양이온의 함량차이도 유의성이 있었으며, 고도와의 차이도 모두 유의성이 있었다. 상기의 음이온, 양이온 함량과 고도와의 요인간의 상관관계분석에서도 정적인 상관관계가 유의하게 나타났다(r=.396, p<001). 결론적으로 본 연구는 제주도 지역의 곶자왈 대기질 중의 이온의 분포에 대한 기초 연구로서 삼림욕을 통한 건강관리에 중요한 정보를 제공하고 있다. 수치함량의 차이를 일정하게 차이를 보이지는 않았으나, 통계적으로는 유의한 차이(p<.001)가 있었다. 양이온 평균수가 낮은 천지연폭포는 90 ions/cm³, 제일 높게 나타난 한라산 수목원의 수는 729.8 ions/cm³ 이었으며, 그 차이는 729.8 ions/cm³ 로 높게 나타났다. 높은 순서로 보면 제일 낮은 천지연 < 1100 m < 동백산 < 제주시 < 사려니 < 원양 < 성판악 < 함덕 < 정방 < 교래B < 절물 < 농장 < 교래A < 한라산 숲길 < 거문오름 < 한라수목원 순으로 측정되었다. 음양이온 모두 지형적으로 낮은 지대와 높은 지역은 함량이 낮게 측정되었다. 음이온과 양이온 및 고도의 분산분석에서 측정지역 간의 함량차이는 모두 유의성이 있었고, 또한 음이온과 양이온의 함량 차이도 유의성이 있었으며, 고도와의 차이도 모두 유의성이 있었다. 상기의 음이온, 양이온 함량과 고도와의 요인간의 상관관계분석에서도 정적인 상관관계가 유의하게 나타났다(r=.396, p<001). 결론적으로 본 연구는 제주도 지역의 곶자왈 대기질 중의 이온의 분포에 대한 기초 연구로서 삼림욕을 통한 건강관리에 중요한 정보를 제공하고 있다.

• 한국습지학회지
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• 제13권3호
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• pp.581-591
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• 2011

김승호 등(2011)에 의해 제안된 둠벙의 유형이 화학적 수환경 특성과 습지식물의 서식 유무를 반영하는지 확인하기 위하여 4가지 유형을 대표하는 CCZ 내 8개의 둠벙에서 습지식물상과 물의 화학적 특성을 조사하였다. 연구결과 샘통형 둠벙에서는 양이온과 음이온의 농도가 모두 낮았으며, 다른 유형의 둠벙에서는 양이온 또는 음이온의 농도가 높았다. 특히 물흐름형 둠벙인 경의선 둠벙에서는 양이온과 음이온이 모두 높게 나타나 지표수가 주로 유입됨을 보여주었다. 대체적으로 물의 화학적 특성과 습지식물상은 둠벙의 유형 분류에 따라 나누어짐을 보였다. 그러나 CCA와 cluster analysis 모두에서 물흐름형 둠벙은 서로 연관성이 없게 나타났다. 이는 둠벙의 분류 시 논과의 물교환보다 급수원이 더 중요함을 의미한다. 그러므로 이를 반영하는 새로운 둠벙 분류체계가 고려되어야 함을 제안한다.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.569-574
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• 2005

A coupled column liquid chromatography system was applied for the separation of the burnup monitors in spent nuclear fuel sample solutions. A reversed phase column was studied for the adsorption behavior of uranyl ions using alpha-hydroxyisobutyric acid as an eluent and used for the separation of plutonium and uranium. A cation exchange column prepared by coating 1-eicosylsulfate onto the reversed phase column was used for the separation of the lanthanides. In addition, retention of Np was checked with the reversed phase column and cation exchange column, respectively, according to the oxidation states to observe the interference effect for the separation of burnup monitors. This chromatography system showed a great reduction in separation time compared to a conventional anion exchange method. A good agreement from the burnup data was obtained between for this method and a conventional anion exchange method to within 1% of a difference for the spent nuclear fuel samples of about 40 GWD/MTU.

• 상하수도학회지
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• 제33권3호
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• pp.205-213
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• 2019

Batch adsorption tests were performed to evaluate the applicability of adsorption kinetic model by using hydrogel chitosan bead crosslinked with glutaraldehyde (HCB-G) for Cu(II) as cation and/or phosphate as anion. Pseudo first and second order model were applied to determine the sorption kinetic property and intraparticle and Boyd equation were used to predict the diffusion of Cu(II) and phosphate at pore and boundary-layer, respectively. According to the value of theoretical and experimental uptake of Cu(II) and phosphate, pseudo second order is more suitable. On comparison with the value of adsorption rate constant (k), phosphate kinetic was 2-4 times faster than that of Cu(II) at any experimental condition indicating the electrostatic interaction between ${NH_3}^+$ and phosphate is dominated at the presence of single component. However, when Cu(II) and phosphate simultaneously exist, the value of k for phosphate was sharply decreased and then the difference was not significant. Both diffusion models confirmed that the sorption rate was controlled by film mass transfer at the beginning time (t < 3 hr) and pore diffusion at next time section (t > 6 hr).

• Asian-Australasian Journal of Animal Sciences
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• 제31권5호
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• pp.677-685
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• 2018

Objective: The objective of the present study was to determine ammonium chloride tolerance of lactating dairy cows, by examining effects of negative dietary cation anion difference (DCAD) induced by ruminal ammonium chloride infusion on performance, serum and urine minerals, serum metabolites and enzymes of lactating dairy cows. Methods: Four primiparous lactating Chinese Holstein cows fitted with ruminal cannulas were infused with increasing amounts (0, 150, 300, or 450 g/d) of ammonium chloride in a crossover design. The DCAD of the base diet was 279 mEq/kg dry matter (DM) using the DCAD formula (Na + K - Cl - S)/kg of DM. Ammonium chloride infusion added the equivalent of 0, 128, 330, and 536 mEq/kg DM of Cl in treatments. According to the different dry matter intakes (DMI), the resulting actual DCAD of the four treatments was 279, 151, -51, and -257 mEq/kg DM, respectively. Results: DMI decreased linearly as DCAD decreased. Yields of milk, 4% fat-corrected milk, energy-corrected milk, milk fat, and milk protein decreased linearly as DCAD decreased. Concentrations of milk protein and milk urea nitrogen increased linearly with decreasing DCAD. Concentration of Cl- in serum increased linearly and concentration of PO43- in serum increased quadratically as DCAD decreased. Urine pH decreased linearly and calculated urine volume increased linearly with decreasing DCAD. Linear increases in daily urinary excretion of $Cl^-$, $Ca^{2+}$, $PO_4{^{3-}}$, urea N, and ammonium were observed as DCAD decreased. Activities of alanine aminotransferase, aspartate aminotransferase, and ${\gamma}-glutamyl$ transferase in serum and urea N concentration in serum increased linearly as DCAD decreased. Conclusion: In conclusion, negative DCAD induced by ruminal ammonium chloride infusion resulted in a metabolic acidosis, had a negative influence on performance, and increased serum enzymes indicating potential liver and kidney damage in lactating dairy cows. Daily ammonium chloride intake by lactating dairy cows should not exceed 300 g, and 150 g/d per cow may be better.