• 지질공학
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• 제34권1호
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• pp.25-38
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• 2024

본 연구에서는 해수와 산성증류수가 암석 풍화에 미치는 영향을 파악하기 위하여 실내인공풍화가속실험을 수행하였다. 70℃의 해수와 산성증류수(pH 3)를 이용하여 총 45회의 동결-융해 실험을 통하여 5종의 유천층군 화산암에 대하여 화학적·물리적 풍화를 모사하였다. 실내인공풍화가속실험 15회와 45회에 각각 물리적 물성과 일축압축강도를 측정하여 풍화 진행에 따른 물성 변화를 추적한 결과, 물리적 물성의 열화는 대부분은 초기 15회 실험에서 발현되었으며, 산성증류수가 해수보다 물리적 물성 변화에 더 많은 영향을 미치는 것으로 파악되었다. 실내인공풍화가속실험에 따른 암종별 일축압축강도의 차이를 통계적으로 평가하기 위하여 분산분석법을 사용하였다. 45회 실험 이후의 대조군에 대한 실험군 시료의 일축압축강도의 감소율은 암종과 물리적 물성 변화 추이와 상관없이 유사하게 나타났지만, 물리적 물성 변화와는 달리, 산성증류수보다 해수가 일축압축강도 변화에 더 많은 영향을 미치는 것으로 파악되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권1호
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• pp.96-102
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• 2011

In this study, we examined the effects of formic acid administration to the drinking water on performance, intestinal microflora and carcass contamination in male broilers. A total of 312 day-old male broiler chicks were allocated to two groups with three replicates. The first group (control) received normal drinking water (pH 7.4) during the experiment. The second group consumed acidified drinking water (pH 4.5) after 5 d of age. At 43 d of age, twelve birds were randomly selected from the control group to determine the effect of acidified drinking water on carcass contamination. These birds were only given normal or acidified (pH 3) drinking water for 8 h prior to slaughter. The reduction of water pH from 7.4 to 4.5 significantly decreased body weights of male broilers at 21 and 42 d of age. However, no differences were observed between male broilers given normal and acidified drinking water in terms of feed intake, feed conversion ratio and mortality. The pH value of the gizzard contents was not significantly affected by acid water treatment. There were no significant differences in the intestinal population of E. coli, total organism and Salmonella between the groups. The total organism and E. coli counts of the carcass slightly decreased in the acidified group. No Salmonella was identified in carcass samples of any of the treatment groups. The results showed that drinking water acidification did not provide beneficial effects on performance, intestinal microflora and carcass contamination in male broilers.

• 한국축산식품학회지
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• 제34권5호
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• pp.591-596
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• 2014

This study evaluated the effect of sodium diacetate and sodium lactate solutions for reducing the cell count of Pseudomonas spp. in frankfurters and hams. A mixture of Pseudomonas aeruginosa (NCCP10338, NCCP10250, and NCCP11229), and Pseudomonas fluorescens (KACC10323 and KACC10326) was inoculated on cooked frankfurters and ham. The inoculated samples were immersed into control (sterile distilled water), sodium diacetate (5 and 10%), sodium lactate (5 and 10%), 5% sodium diacetate + 5% sodium lactate, and 10% sodium diacetate + 10% sodium lactate for 0-10 min. Inoculated frankfurters and ham were also immersed into acidified (pH 3.0) solutions such as acidified sodium diacetate (5 and 10%), and acidified sodium lactate (5 and 10%) in addition to control (acidified distilled water) for 0-10 min. Total aerobic plate counts for Pseudomonas spp. were enumerated on Cetrimide agar. Significant reductions (ca. 2 Log CFU/g) in Pseudomonas spp. cells on frankfurters and ham were observed only for a combination treatment of 10% sodium lactate + 10% sodium diacetate. When the solutions were acidified to pH 3.0, the total reductions of Pseudomonas spp. were 1.5-4.0 Log CFU/g. The order of reduction amounts of Pseudomonas spp. cell counts was 10% sodium lactate > 5% sodium lactate ${\geq}$ 10% sodium diacetate > 5% sodium diacetate > control for frankfurters, and 10% sodium lactate > 5% sodium lactate > 10% sodium diacetate > 5% sodium diacetate > control for ham. The results suggest that using acidified food additive antimicrobials, as dipping solutions, should be useful in reducing Pseudomonas spp. on frankfurters and ham.

• Animal Bioscience
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• 제35권6호
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• pp.902-915
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• 2022

Objective: Diet acidification supplementation is known to influence intestinal morphology, gut microbiota, and on phosphorus (P) utilization of broilers. Alterations in intestinal barrier and microbiota have been associated with systemic inflammation and thus regulating bone turnover. Hence the effect of acidifier addition to drinking water on tibia mass and the linkages between intestinal integrity and bone were studied. Methods: One-d-old male broilers were randomly assigned to normal water (control) or continuous supply of acidified water (2% the blend of 2-hydroxy-4-methylthiobutyric acid, lactic, and phosphoric acid) group with 5 replicates of 10 chicks per replicate for 42 d. Results: Acidification of drinking water improved the ash percentage and calcium content of tibia at 42 d. Broilers receiving acidified water had increased serum P concentration compared to control birds. The acidified group showed improved intestinal barrier, evidenced by increased wall thickness, villus height, the villus height to crypt depth ratio, and upregulated mucin-2 expression in ileum. Broilers receiving drinking water containing mixed organic acids had a higher proportion of Firmicutes and the ratio of Firmicutes and Bacteroidetes, as well as a lower population of Proteobacteria. Meanwhile, the addition of acidifier to drinking water resulted in declined ileal and serum proinflammatory factors level and increased immunoglobulin concentrations in serum. Concerning bone remodeling, acidifier addition was linked to a decrease in serum C-terminal cross-linked telopeptide of type I collagen and tartrate-resistant acid phosphatase reflecting bone resorption, whereas it did not apparently change serum alkaline phosphatase activity that is a bone formation marker. Conclusion: Acidified drinking water increased tibia mineral deposition of broilers, which was probably linked with higher P utilization and decreased bone resorption through improved intestinal integrity and gut microbiota and through decreased systemic inflammation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.350-353
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• 2004

in order to develop a new technique for the removal of arsenic compoundsfrom acidified water, the removal of arsenic compounds by an acidophilic moss, Jungermannia vulcanicola Steph. was investigated in this study. The result of vial tests for arsenic removal is dependent on the biological activity of moss. The presence of phosphate inhibited the arsenic removal. And the acclimatization of moss by the media containing arsenic increased the its capability of arsenic remova.

• Journal of the Korean Wood Science and Technology
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• 제21권2호
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• pp.9-14
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• 1993

Weathering of wood in a region of acid rain was performed by the test which thin veneers of Sitka spruce were exposed to outdoor weathering for a total of 18 weeks, with a daily soaking for 30 minutes in acidified water in the pH range 2~5.6. The weathering measured by weight loss and loss in maximum failure load in tension was accelerated by the increase in the acidity of acidified water and in the period of outdoor exposure. It was also shown that the weathering was accelerated even with low acidic conditions in the case of long exposure period, although the weathering was rapidly accelerated with high acidic conditions. When compared the degree of weight loss with that of loss in failure load by weathering, the latter was much greater. From the results of this research, it could be concluded that at pH 4.0 or below of precipitation, the acceleration of weathering of exterior wood would become serious problems, which would be caused deterioration in performance of exterior wood.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.705-712
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• 2006

Influences of urea treated corncobs (UTC) ensiled with or without different additives on ruminal characteristics, in situ digestion kinetics, nutrient digestibility and nitrogen metabolism were examined in a $5{\times}5$ Latin square design using five ruminally cannulated buffalo bulls. Five iso-caloric and iso-nitrogenous diets were formulated to contain 30% dry matter (DM) from concentrate and 70% DM from 5% UTC ensiled without any additive (U) or with 5% enzose (EN), 5% acidified molasses (AM), 5% non-acidified molasses (NM) and 5% acidified water (AW), respectively. These diets were fed to buffalo bulls at 1.5% of their body weight daily. Ruminal $NH_3$-N concentration at 3 hours (h) post feeding was significantly higher in bulls fed U, NM and AW diets, however, at 6, 9 and 12 h post feeding it was significantly higher in bulls fed EN and AM diets. Ruminal total volatile fatty acids (VFA) and acetate concentrations were significantly higher with EM and AM diets compared with other diets at 3, 6, 9 and 12 h post feeding. Ruminal pH at 6 and 9 h post feeding was higher with EN and AM diets; however; it was notably lower with these diets at 3 h post feeding. Total ruminal bacterial and cellulolytic bacterial counts were higher in bulls fed EN and AM diets than in those fed the other diets. In situ ruminal DM and NDF degradabilities and total tract digestibilities were significantly higher with UTC ensiled with enzose and acidified molasses than those ensiled without any additive or other additives. Nitrogen balance was significantly higher in bulls fed EN and AM diets than those fed U, AW and NM diets. The UTC ensiled with enzose or acidified molasses resulted in better digestibility and N utilization than those ensiled without any additive, with non-acidified molasses and acidified water in buffaloes.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.266-268
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• 2008

The antimicrobial effect of acidified sodium chlorite (ASC) solution on whole croaker skin was evaluated. Whole croaker skin was treated with ASC (50, 100, 200, 400, and 600 ppm) and distilled water. After 10-minute exposure to 600 ppm ASC, 8% of Gram-negative bacteria survived on the whole croaker sample. Treatment with 50 ppm ASC eliminated all coliforms in the initial load. Immersion treatment with 600 ppm ASC resulted in $1.3\;log\;CFU/cm^2$ greater kill of the initial mesophile loads of control ($2.8\;log\;CFU/cm^2$) than distilled water. Fifty ppm ASC solution produced a 1.6-log reduction of psychrotrophic bacteria. ASC treatment was an effective method for reducing naturally occurring microflora on whole croaker skin.

• 펄프종이기술
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• 제43권2호
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• pp.57-65
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• 2011

Pulping of paper mulberry (Broussonetia kazinoki) white bast has been examined by novel atmospheric pressure pulping methods. The viscosity of pulp has been found to be highly sensitive and variable with pulping methods. Therefore, selections of pulping chemicals and conditions are very important. Two kinds of pulping procedures were employed for the high viscosity pulp manufacturing. The one is ammonium oxalate treatment and the other is sodium chlorite and acetic acid treatment. Not only chemical components and pulp yields which of paper mulberry white bast but also water retention value (WRV), whiteness index, yellowness index, and colors of every pulp were examined. The hot water, 1% NaOH, and ethanol-benzene extractives which of paper mulberry white bast were 4.48%, 28.45%, and 2.84%, respectively. The contents of holocellulose, lignin, and ash were 90.66%, 1.05%, and 2.18%, respectively. In the pulp yields, group 1 which treated with only ammonium oxalate were 77.04-81.71%, group 2 which treated with ammonium oxalate and acidified sodium chlorite separately and washed between first and second stages were 64.15-83.90%, group 3 which treated with ammonium oxalate and acidified sodium chlorite separately and not washed between first and second stages were 57.35-73.17%, and group 4 which treated with mixed ammonium oxalate and acidified sodium chlorite were 66.58-68.43%. The pulps treated with acidified sodium chlorite showed high whiteness index, but the pulps treated with only ammonium oxalate showed high yellowness index. Variations in the combinations of treatments resulted in different pulp characteristics.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.801-809
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• 2013

We investigate sensitivity and limit of detection (LOD) of trace copper (Cu) metal using pristine carbon nanotube (CNT) and acidified CNT (ACNT) electrodes. Squarewave based anodic stripping voltammetry (SWASV) is used to determine the stripped Cu concentration. Prior to performing the SWASV measurements, its optimal conditions are determined and with that, effects of potential scan rate and $Cu^{2+}$ concentration on stripping current are evaluated. The measurements indicate that (1) ACNT electrode shows better results than CNT electrode and (2) stripping is controlled by surface reaction. In the given $Cu^{2+}$ concentration range of 25-150 ppb, peak stripping current has linearity with $Cu^{2+}$ concentration. Quantitatively, sensitivity and LOD of Cu in ACNT electrode are 9.36 ${\mu}A\;{\mu}M^{-1}$ and 3 ppb, while their values are 3.99 ${\mu}A\;{\mu}M^{-1}$ and 3 ppb with CNT electrode. We evaluate the effect of three different water solutions (deionized water, tap water and river water) on stripping current and the confirm types of water don't affect the sensitivity of Cu. It turns out by optical inspection and cyclic voltammetry that superiority of ACNT electrode to CNT electrode is attributed to exfoliation of CNT bundles and improved interfacial adhesion occurring during oxidation of CNTs.