• Title/Summary/Keyword: pH variation

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Improvement of Verification Method for Remedial Works through the Suggestion of Indicative Parameters and Sampling Method (정화 보조지표와 시료 채취 방법 제안을 통한 토양정화검증 제도 개선 연구)

  • Kwon, Ji Cheol;Lee, Goontaek;Kim, Tae Seung;Yoon, Jeong-Ki;Kim, Ji-in;Kim, Yonghoon;Kim, Joonyoung;Choi, Jeongmin
    • Journal of Soil and Groundwater Environment
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    • v.21 no.6
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    • pp.179-191
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    • 2016
  • In addition to the measurement of the concentration of soil contaminants, the new idea of indicative parameters was proposed to validate the remedial works through the monitoring for the changes of soil characteristics after applying the clean up technologies. The parameters like CFU (colony forming unit), pH and soil texture were recommended as indicative parameters for land farming. In case of soil washing, water content and the particle size distribution of the sludge were recommended as indicative parameters. The sludge is produced through the particle separation process in soil washing and it is usually treated as a waste. The parameters like water content, organic matter content, CEC (cation exchange capacity) and CFU were recommended as indicative parameters for the low temperature thermal desorption method. Besides the indicative parameter, sampling methods in stock pile and the optimal minimum amount of composite soil sample were proposed. The rates of sampling error in regular grid, zigzag, four bearing, random grid methods were 17.3%, 17.6%, 17.2% and 16.5% respectively. The random grid method showed the minimum sampling error among the 4 kinds of sampling methods although the differences in sampling errors were very little. Therefore the random grid method was recommended as an appropriate sampling method in stock pile. It was not possible to propose a value of optimal minimum amount of composite soil sample based on the real analytical data due to the dynamic variation of $CV_{fund{\cdot}error}$. Instead of this, 355 g of soil was recommended for the optimal minimum amount of composite soil sample under the assumption of ISO 10381-8.

Determination of Terazocin in Human Plasma by Liquid Chromatography and Bioequivalence Study of Teratonin® Tablets (액체크로마토그래프법에 의한 사람 혈장 중 테라조신의 정량 및 테라토닌® 정의 생물학적 동등성)

  • Cho, Eun-Sook;Kang, Sung-Ha;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.32 no.2
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    • pp.119-125
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    • 2002
  • A rapid, selective and reproducible high-performance liquid chromatographic method has been developed for the determination of terazocin in human plasma. Terazocin plus the internal standard, prazocin hydrochloride, were extracted from alkalified plasma with tert-butylmethyl ether, back-extracted into 0.05% phosphoric acid. Fifty ${\mu}l-portions$ of extract were injected onto a octadecylsilane column and eluted with a mixture of acetonitrile, water and triethylamine (30 : 70 : 0.1 v/v, adjusted to pH 5.0 with dilute phosphoric acid) at a flow rate of 1.0 ml/min. The fluorescence intensity of column eluents was monitored at excitation wavelength of 250 nm and emission wavelength of 370 nm. No interference peaks were observed. The practical limit of quantitation was 5 ng/ml for terazocin. The average intraday and interday coefficients of variation were 4.15 and 3.54%, respectively. Also intraday and interday precisions over the range $5{\sim}60\;ng/ml$ were $0.49{\sim}2.92\;and\;0.38{\sim}5.12%$, respectively. The bioequivalence of two terazosin tablets, the $Hytrine^{\circledR}$ (Il Yang Pharmaceutical Co., Ltd.) and the $Teratonin^{\circledR}$ (Sam-A Pharmaceutical Co., Ltd.), was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Sixteen healthy male volunteers $(24.6{\pm}2.0\;years\;old)$ were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 2 mg of terazosin was orally administered, blood was taken at predetermined time intervals and the concentration of terazosin in plasma was determined with a HPLC method using spectrofluorometric detector. AUC was calculated by the linear trapezoidal method. $C_{max}\;and\;T_{max}$ were compiled from the plasma drug concentration-time data. Analysis of variance (ANOVA) was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between the two preparations were 0.21 %, 5.53% and 8.82%, respectively. The powers $(1-{\beta})\;for\;AUC_t,\;C_{max}\;and\;T_{max}$ were >99%, 97.49%, and 33.26%, respectively. Minimum detectable differences $({\Delta},\;%)\;at\;{\alpha}=0.1\;and\;1-{\beta}=0.8$ and the 90% confidence intervals were all less than ${\pm}20%$ except for $T_{max}.\;AUC_t\;and\;C_{max}$ met the criteria of KDFA for bioequivalence, indicating that $Teratonin^{circledR}$ tablets are bioequivalent to $Hytrine^{circledR}$ tablets.

Community Structure and Distribution Pattern of the Pleuronectiform Fishes in the Uljin Marine Ranching Area, Korea (울진바다목장에서 어획된 가자미목(Pleuronectiformes) 어류의 군집구조 및 공간분포)

  • Yoon, Byoung Sun;Park, Jeong-Ho;Sohn, Myong Ho;Yang, Jae Hyeong;Yoon, Sang Chul;Choi, Young Min
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.413-423
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    • 2013
  • To elucidate the variation of species composition, biomass and length distribution of flatfishes by the period and region in the Uljin marine ranching area, bottom trawl survey was investigated at the six stations from Feb. 2008 to Dec. 2010. During the survey period, a total 4 families 17 species in the Pleuronectiformes, average 69,158 $ind./km^2$ and 5,625 $kg/km^2$ were identified, in 2008 appeared in 14 species, average 25,798 $ind./km^2$ and 2,333 $kg/km^2$ and in 2009 appeared in 13 species, average 102,360 $ind./km^2$ and 5,634 $kg/km^2$ and in 2010 appeared in 14 species, average 75,704 $ind./km^2$ and 8,632 $kg/km^2$. The individual dominant species, occupying over 10% of total individuals, was Pleuronectes herzensteini (20,811 ind., 30.0%), Hippoglossoides pinetorum (18,666 ind., 26.9%) and Glyptocephalus stelleri (13,499 ind., 19.4%) also the biomass dominant species, occuping over 10% of total biomass, was P. herzensteini (2,207 kg, 39.3%), Pleuronectes yokohamae (857 kg, 15.3%), H. pinetorum (761 kg, 13.5%), Kareius bicoloratus (677 kg, 12.1%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals in the Uljin marine ranching area from Feb. 2008 to Dec. 2010 was divided into two different groups of the flatfishes community in 2008 and from Jan. to Apr. in 2009 and 2010 (Group A) and the pleuronectiform community in from May to Dec. in 2009 and 2010 (Group B). From the cluster and MDS analysis using the similarity of demersal organisms community among six stations, the Uljin marine ranching area was divided into two different groups of Group 1 (St. 1 and St. 3) and Group 2 (St. 2, St. 4, St. 5 and St. 6).

A Study on the Microflora of the Han River(II) The phytoplanktons and its seasonal variaton in the area of the Chun-chon and the Chung-pyong reservoir of the Han River (한강의 Microflora에 관한 연구 (제2보) 춘천 및 청평정수지를 중심으로 한 한강의 식물성 planktond과 그 계절적 소장)

  • 정영호
    • Journal of Plant Biology
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    • v.11 no.2
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    • pp.1-30
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    • 1968
  • The Han River was investigated monthly from April through September, 1967 at Chun-chon reservoir, Shin-yean, So-yang, Chung-pyong reservoir, Yang-soo-ri and Gi-doo-won to clarify the phytoplankton and to study its seasonal variation. At the same time, vertical distribution of phytoplankton was also studied from June through September at Chun-chon and Chung-pyong reservoir. The results obtained are as follows: As the environmental conditions, water temperature, dissolved oxygen, pH, and transparency were determined. The plankton samples collected from six stations were identified and classified by Engler's classification system. It resulted in 4 phyla, 4 classes, 3 subclasses, 13 orders, 27 families, 5 tribes, 71 genera, 222 species, 1 subspecies, 51 varieties and 2 forms. The total number of phytoplankton identified was 276. Of them, 84 species, 1 subspecies 26 varieties, 2 forms were recorded in this paper for the first time. Considering with the habitat of the total number of phytoplanktons, the highest percentage of Limnoplankton existed in the Chung-pyong reservoir. It suggests that hte Chung-pyong reservoir is becoming to have the character of lake. The planktons appeared commonly during six months at six station belong to Chrysophyta including 22 species in 11 genera. Among these 22 species, Navicula, consists of 6 species, was the most abundant. The number of species identified uniquely at each station were 5 species in the Chun-chon reservoir, 6 in Chung-pyong and Yang-soo-ri, 8 at Shin-yean, 11 at So-yang, and 18 at Gi-doo-won. The number of species occurred at all stations were 29 in spring, 42 in Autumn and during investigation period. The maximum production of total phytoplankton was generally shown in the late spring and the early fall with differences in quantity at six collecting statins. In the Chun-chon reservoir, the high concentration of approximately 1, 190, 000 cells per litter in the months of August and September was due to the increase of Chrysophyte genus, Melosira and the highest concentration of approximately 2, 000, 000 in July at Gi-doo-won was caused Chlorophyte genus, Secenedesmus. The Chun-chon reservoir of three years old was different from the Chung-pyong reservoir of 25 years old with respect to increase in Melosira genus in August and September. After the completion of the Ui-am reservoir, though there was an increase in total density, the number of species of phytoplankton was not changed. It suggests that Ui-am reservoir is similar to the Chun-chon reservoir under the influence of the latter. The density of total phytoplankton was generally high at the depth of 2m to 5m for the two reservoirs.

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Simultaneous Determination of B Group Vitamins in Supplemented Food Products by High Performance Liquid Chromatography-Diode Array Detection

  • Suh, Joon-Hyuk;Yang, Dong-Hyug;Lee, Byung-Kyu;Eom, Han-Young;Kim, Un-Yong;Kim, Jung-Hyun;Lee, Hye-Yeon;Han, Sang-Beom
    • Bulletin of the Korean Chemical Society
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    • v.32 no.8
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    • pp.2648-2656
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    • 2011
  • A simple HPLC-DAD method was developed and validated to determine B group vitamin content (thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxine and folic acid) in supplemented food samples, i.e., infant formula, cereal, low-calorie food, a multi-vitamin pill and a vitamin drink. In this study, the most significant advantages were simultaneous determination of the six B group vitamins in various food matrices and a small number of sample treatment steps that required only an organic solvent, acetonitrile. Moreover, this method prevents reduction of column durability, because the mobile phase does not contain ion-pairing reagents. Analytes were separated on a Develosil RPAQUEOUS $C_{30}$ (4.6 mm ${\times}$ 250 mm, 5 ${\mu}M$ particle size) column with a gradient elution of acetonitrile and 20 mM phosphate buffer (pH 3.0) at a flow rate between 0.8 and 1.0 mL/min. Detection was performed at 275 nm, except for that of pantothenic acid (205 nm). The calibration curves for all six vitamins showed good linearity with correlation coefficients ($r^2$) higher than 0.995. The developed method was validated with respect to linearity, intra- and inter-day accuracy and precision, limit of quantification (LOQ), recovery and stability. The method showed good precision and accuracy, with intra- and inter-assay coefficients of variation less than 15% at all concentrations. The recovery was carried out according to the standard addition procedure, with yields ranging from 89.8 to 104.4%. This method was successfully applied to the determination of vitamin B groups in supplemented food products.

Nitrogen Removal Characteristic of Excreta Wastewater Using SBR and MBR Processes (SBR 및 MBR 공정을 이용한 분뇨폐수에서의 질소제거 특성)

  • Jung, Jin-Hee;Yoon, Young-Nae;Lee, Seul-Kee;Han, Young-Rip;Lee, Seung-Chul;Choi, Young-Ik
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1485-1491
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    • 2015
  • There are two treatment processes that are currently applied to ships are the biological treatment process using the activated sludge and the electrochemical treatment. However, neither of them are able to remove both nitrogen and phosphorus due to their limited ability to remove organic matters, which are main causes of the red tide. This study was conducted to identify the characteristics of nitrogen removal factors from manure wastewater by replacing the final settling tank in SBR (Sequencing Batch Reactor) process and applying immersion type hollow fiber membrane. SBR process is known to have an advantage of the least land requirement in special environment such as in ship and the immersion type hollow fiber membrane is more stable in water quality change. As the result, the average in the cases of DO (Dissolved Oxygen) is 2.9(0. 6~3.9) mg/L which was determined to be the denitrifying microorganism activity in anaerobic conditions. The average in the cases of ORP (Oxidation Reduction Potential) is 98.4~237.3 mV which was determined to be the termination of nitrification since the inflection point was formed on the ORP curve due to decrease in the stirring treatment after the aeration, same as in the cases of DO. Little or no variation in the pH was determined to have positive effect on the nitrification. T-N (Total Nitrigen) removal efficiencies of the finally treated water were 71.4%, 72.3% and 66.5% in relatively average figures, thus was not a distinct prominence. In being applied in ships in the future, the operating conditions and structure improvements are deemed necessary since the MEPC (Marine Environment Protection Committee). 227(64) ship sewage nitrogen is less than the standard of 20 Qi/Qe mg/L or the removal rate of 70%.

Seasonal Variation in Community Structure of Subtidal Seaweeds in Jeju Island, Korea (제주도 주변 해역 조하대 해조류 군집구조의 계절적 변동)

  • Kim, Bo Yeon;Ko, Jun-Cheol;Ko, Hyuck Joon;Park, Sung Eun;Cha, Hyung Kee;Choi, Han Gil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.607-618
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    • 2013
  • Marine macroalgal community structures and characteristics of ocean environmental factors were examined seasonally at four sites in Jeju Island, Korea, from March to November 2012. A total of 71 macroalgal species were identified, including 9 green, 7 brown, and 55 red algae. Peyssonnelia capensis occurred at all study sites and in all seasons. The average annual biomass of seaweed was 991.84 g wet $wt/m^2$, with seasonal variations from 543.80 g in autumn to 1,284.17 $g/m^2$ in summer. A green alga, Codium coactum, was the dominant species, occupying 21.31% (211.39 $g/m^2$) of the total algal biomass in Jeju Island. Subdominant species were Ecklonia cava and Lithophyllum okamurae, comprising 20.85% (206.75 $g/m^2$) and 19.64% (194.75 $g/m^2$), respectively, of the total algal biomass in Jeju Island. The vertical distribution of subtidal seaweeds was represented by L. okamurae at 5 m depth, C. coactum at 10 m depth, E. cava at 5-10 m depth and P. capensis at the 20 m depth level. In the present study, crustose coralline algae, which predominated on barren ground, were subdominant species at all study sites. Community indices varied between 0.51-0.63 for dominance index (DI), 5.53-8.14 for richness index (R), 0.51-0.63 for evenness index (J'), and 2.04-2.32 for diversity index (H'). On the basis of seaweed biomass and community indices, Sinchang was the best preserved coastal area, showing maximal values in biomass, and evenness- and diversity-indices, and minimal value in the dominance index, representing stable environmental conditions. In contrast, the Onpyung and Topyeong sites, located near tourist venues such as Udo and Seogwipo were relatively poor habitats based on community indices and biomass. The present results could imply that climate changes alter seaweed community structure, and long-term monitoring of the study sites is required.

Temporal-spatial Variations of Water Quality in Gyeonggi Bay, West Coast of Korea, and Their Controlling Factor (한국 서해 경기만 연안역에서 수질환경의 시.공간적 변화 특성과 조절 요인)

  • Lim, Dhong-Il;Rho, Kyoung-Chan;Jang, Pung-Guk;Kang, Sun-Mi;Jung, Hoi-Soo;Jung, Rae-Hong;Lee, Won-Chan
    • Ocean and Polar Research
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    • v.29 no.2
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    • pp.135-153
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    • 2007
  • Temporal (seasonal) and spatial distributions and variations of various physico-chemical factors (salinity, temperature, pH, DO, COD, SPM, POC, silicate, DIP, DIN) in surface and bottom waters were studied in the coastal environment with typical macro-tidal range and monsoonal weather condition, Gyeonggi Bay, west coast of Korea. Spacial distribution patterns of these factors were generally similar to each other, and appeared to be inversely related to the distribution pattern of salinity, suggesting that water quality of the study area was primarily controlled by the physical mixing process of Han-River freshwater with nearby coastal seawater. During flooding season, silicate- and nitrogen-rich Han River water directly flowed into offshore as far as $20\sim30\;km$ from the river mouth, probably causing serious environmental problems such as eutrophication and unusual and/or noxious algal bloom, etc. Except the surface water during summer flooding season, high concentrations of nutrients appeared generally in dry season, whereas low values in spring, possibly because of the occurrence of spring phytoplankton bloom. On the other hand, nutrient flux through the estuary seems to be primarily depending on river discharge, sewage discharge and agricultural activities, especially during the rainy season. Also, nutrients in this coastal waters are considered to be supplied from the sediments of tidal-flats, which developed extensively around the Han-River mouth, especially during fall and winter of dry and low discharge seasons, possibly due to the stirring of tidal flat sediments with highly enriched pore-water nutrients by storm. And also, COD and DIN concentrations in the study area consistently increased during the last 20 years, probably because of agricultural activities and increasing discharge of industrial and domestic wastes.

Quality Characteristics and Antioxidant Activities of Commercial Jeupjang (일부 시판 즙장의 품질 특성 및 항산화 활성)

  • Kim, Ha-Yun;Hwang, In-Guk;Yoo, Seon-Mi;Hwang, Young;Cha, Sung-Mi;Kim, Haeng-Ran
    • The Korean Journal of Community Living Science
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    • v.21 no.4
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    • pp.571-579
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    • 2010
  • Jeupjang has long been considered only a local delicacy. So, it has gradually been forgotten because its name and definition have not been established. This study was performed in order to provide some basic data by comparing the general components, color, free amino acids, free sugar, organic acids and antioxidant activities between commercial Jeupjang(GG, GD, JM, NJ, NS). Moisture contents, crude protein, crude fat and crude ash contents of Jeupjang were 48.07~61.77%, 4.08~10.53%, 3.92~4.64%, and 3.63~9.95%. pH, titrable acidity and salt in Jeupjang were 4.32~5.50, 9.37~14.82 mL(1N-NaOHmL), and 3.27~8.90%. Amino-type nitrogen content is 42.05~ 138.83mg%. Lightness(L), redness(a) and yellowness(b) values in color of Jeupjang were10.04~21.89, 18.92~28.80, and 17.16~37.56. The total content of free amino acids in commercial Jeupjang ranged from 35.22mg% to 306.02mg% in which it showed wide variation among samples. The major free amino acids were glutamic acid, aspartic acid, alanine and proline. The major free sugars were fructose(0.31~1.60%), glucose(6.20~ 13.61%) and maltose(7.34~10.01%). The major organic acids were succinic acid(29.08~ 103.62 mg%) and citric acid(3.08~108.69 mg%). Total polyphenol contents were from 1.16 mg/g to 1.78 mg/g, DPPH radical scavenging activity is from 0.57 AEAC to 1.53 AEAC and ABTS radical scavenging activity is from 1.58 AEAC to 2.85 AEAC. This result might cause the differences of soybean composition, processing methods and brewing periods. For the succession of traditional fermented food such as Jeupjang, quality standards are required. To this end, the standardization of manufacturing processes must be followed.

Growth and Fruit Characteristics of Highbush Blueberry by Mulching Materials (멀칭 자재가 하이부쉬블루베리 생육 및 과실 특성에 미치는 영향)

  • Kim, Su-Jin;Lee, Dong-Hoon;Hur, Youn-Young;Im, Dong-Jun;Park, Seo-Jun;Jung, Sung-Min;Chung, Kyeong-Ho
    • Korean Journal of Organic Agriculture
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    • v.28 no.2
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    • pp.209-221
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    • 2020
  • Highbush blueberries (Vaccinium corymbosum), 'Duke', 'Bluecrop', and 'Elliott', were applied with ground cover mulch systems to evaluate bush growth and fruit characteristics. Soil temperature variation was lower in the woodchip mulching plot. Therefore, CEC, soil pH, phosphate, mineral ions were not significantly different among mulching materials. The number of main stem was higher in woodchip > sawdust > rice husk > plastic film mulching plot, respectively. Total shoot number was also higher in organic mulching plots than in plastic film plot. However, total shoot number was not significantly different among the organic mulching plots. Fruit weight was the highest in the woodchip mulching plot of all blueberry cultivars, however, soluble sugar content, organic acidity, fruit firmness were not significantly different in mulching materials. Yield was higher in organic mulching plots than in plastic film plot in all blueberry cultivars. Especially, yield per shrub of woodchip plots was the highest about 3.6 kg in 'Duke', 2.7 kg in 'Bluecrop', and 2.6 kg in 'Elliott'. Furthermore, correlation of main stem number and yield was highly significant (r2 = 0.8413). Therefore, woodchip mulching is expected to be an eco-friendly method to increase the number of stems and the yield of blueberries.