• Title/Summary/Keyword: pH conditions

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Effect of Coagulants and Separation Methods on Algal Removal in Water Treatment Process (정수처리에서 응집제 종류와 분리공정이 조류 제거에 미치는 영향)

  • Park, Hung-Suck;Lee, Sang-Yoon
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.2
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    • pp.279-289
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    • 2000
  • The objective of this study was to investigate the effect of coagulants and solid-liquid separation methods on algal removal in water treatment processes. Thus characterization of raw water quality in terms of turbidity. UV-254, $KMnO_4$ consumption, chlorophyll-a and correlation analysis of these parameters were conducted. In addition, the effect of commercial Al-based coagulants(Alum. PAC and PACS) on algal removal was studied by turbidity and organic removal, algal species removal, characteristic of pH drop and alkalinity consumption using laboratory jar tests. Organic components including UV-254, $KMnO_4$ consumption, chlorophyll-a in case of algal bloom were highly correlated with turbidity and the correlation coefficients of UV-254, $KMnO_4$ consumption, chlorophyll-a with turbidity were 0.775, 0674 and 0.623, respectively. In coagulation and sedimentation, the Al-based coagulants showed similar efficiency of organic and turbidity removal in low organic($KMnO_4$ consumption below 15mg/l) and low turbidity(below 30NTU). However, PAC and PACS showed better algal removal than alum in high organic concentration($KMnO_4$ consumption above 20mg/l) and high turbidity(above 100NTU) raw water conditions generated by high algal growth, which is considered to be due to the floc settleability. In comparison of sedimentation and flotation after chemical coagulation and flocculation, the removal efficiency of organic and turbidity were higher in case of alum dose with flotation than with sedimentation, while those were better in case or PAC and PACS with sedimentation than with flotation. Thus, Alum with flotation and PAC and PACS with sedimentation is recommended for efficient algal removal. The dominant phytoplankton in raw water were Microcystic and pediastrum simplex and the removal efficiency of algae with sedimentation using alum. PAC and PACS were 27%, 45% and 22% respectively, while those with DAF showed 100% removal of phytoplankton and zooplankton.

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Physico-Chemical Analysis and Antioxidant Activities of Korea Aronia melanocarpa (국내산 아로니아의 이화학 분석 및 항산화 활성)

  • Choi, Kyeong-Hee;Oh, Hyun Jeong;Jeong, Young Jae;Lim, Eun Jeong;Han, Jin Soo;Kim, Ji Hyun;Kim, Oh Young;Lee, Hyun-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.8
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    • pp.1165-1171
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    • 2015
  • In this study, we examined the effects of cultivation adaptability and product quality of aronia (fruit of Aronia melanocarpa) cultivated in various domestic regions. Extracts of aronia cultivated in various domestic regions and Poland were measured for their total sugar contents, acidities, total polyphenol contents, anthocyanin contents, and antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Our results showed that aronia extracts from the two countries had similar sugar contents, acidities, and anthocyanin contents. Anthocyanin is an important functional component of Aronia melanocarpa. Extracts of aronia from the two countries contained cyanidin-3-galactoside (65.5~69.1%) as the major anthocyanin compound. Aronia cultivated in C region showed higher polyphenol content (121.5%) than Poland aronia and we measured of antioxidant activities by DPPH ($IC_{50}$) and FRAP assay. Aronia cultivated in C region showed the highest antioxidant activity and polyphenol contents. Cultivation conditions of C region had sufficient sunshine and soil with pH of 6.5. From the above results, Korean aronia had similar activities with Poland aronia, which suggests that it can be a new potential development source and high technological foods.

Biochemical Properties of Lactate Dehydrogenase Eye-Specific C4 Isozyme: Lepomis macrochirus and Micropterus salmoides (젖산탈수소효소 eye-specific C4 동위효소의 생화학적 특성: 파랑볼우럭(Lepomis macrochirus)과 큰입우럭(Micropterus salmoides))

  • Yum, Jung-Joo;Ku, Bo-Ra
    • Journal of Life Science
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    • v.22 no.2
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    • pp.209-219
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    • 2012
  • The properties of lactate dehydrogenase (LDH, EC 1.1.1.27) eye-specific $C_4$ isozyme were studied by polyacrylamide gel electrophoresis, Western blotting, immunoprecipitation, and enzyme kinetics. Furthermore, we proposed the optimal conditions for measuring the activity of LDH eye-specific $C_4$ isozyme. The isozymes were detected in the cytosol of eye tissues from Lepomis macrochirus and Micropterus salmoides and were more similar to the $A_4$ than the $B_4$ isozyme. LDH/CS in the eye tissue of L. macrochirus was increased in September, so the ratio of anaerobic metabolism was high. The electrophoretic patterns of mitochondrial LDH were similar to those of cytosolic LDH in the eye tissues of L. macrochirus and Micropterus salmoides. LDH eye-specific $C_4$ isozyme from eye tissue was purified by preparative native-PAGE. The activities of LDH eye-specific $C_4$ isozymes in L. macrochirus and M. salmoides were reduced at concentrations greater than 0.2 mM and 0.1 mM of pyruvate, respectively. These concentrations remained at 5.2% and 15.8% as a result of the inhibition by 10 mM of pyruvate, so the degree of inhibition was very high. The LDH activities of eye tissues were reduced at concentrations greater than 22 mM and 24 mM of lactate, respectively, in L. macrochirus and M. salmoides. The ${K_m}^{PYR}$ of eye-specific $C_4$ was 0.088 mM in L. macrochirus and it was 0.033 mM in M. salmoides. The activities of cytosolic and mitochondrial eye-specific $C_4$ isozymes were high in ${\alpha}$-ketobutyric acid. Furthermore, the activities of eye tissue and eye-specific $C_4$ isozyme had to be measured with 0.5 mM of pyruvate and a buffer solution of pH 7.5. As a conclusion, the eye-specific $C_4$ isozyme in M. salmoides has a high affinity for pyruvate and exhibits maximum activity at a lower concentration of pyruvate and at higher concentration of lactate than that in L. macrochirus. Therefore, it seems that the energy produced by the LDH eye-specific $C_4$ isozyme in M. salmoides was used at the first stage of predatory behavior.

A Study on Soil Characteristics of Poorly Vegetation Space for Landscape Remodeling Planning on Apartment Complex (아파트 조경 식생불량공간 리모델링 설계를 위한 토양특성 연구)

  • Han, Seung-Won;Kim, Kwang Jin;Yun, Ji Hye;Jeong, Na Ra;You, Soo Jin
    • Korean Journal of Environment and Ecology
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    • v.34 no.1
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    • pp.85-92
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    • 2020
  • The purpose of this study is to provide base information that can be utilized in surveying the status of landscape management within apartment complexes and grasping the conditions of the soil for planting plants, as a way to improve the quality of green spaces by repairing poorly vegetated spaces within apartment complexes and remodeling them with diverse species of plants. Considering that trees and shrubs of equal sizes are simultaneously planted upon the completion of apartment complexes, they were divided based on their completion year at the interval of 5 years and differences in the growth of trees and the components of soil over time were analyzed. Out of the species of trees planted in all the 9 apartment complexes surveyed in this study, the growth of 4 species of needleleaf trees and 4 species of broadleaf trees were surveyed. Juniperus chinensis 'Kaizuka' and Pinus densiflora Siebold & Zucc. out of the needleleaf trees and Malus floribunda Siebold ex Van Houtte out of the broadleaf trees showed the highest growth rate when over 5 years passed after planting and their growth rate decreased when over 10 years passed. Platycladus orientalis and Acer palmatum Thunb. in the apartment complexes that were built over 10 years ago showed the highest growth rate, which indicates that the species require a relatively long period of time for growth. The hardness of the soil at the areas where trees were planted but their soil surface was bare was analyzed. When over 5 years passed after the completion of apartment complexes, over 20 mm of the soil was found to be stamped. The physicochemical properties of soil were also surveyed and the pH level was found to have been continuously high ever since the completion. The organic content in the surveyed soil was about 1/3 of the content in fertile soil, which means that additional fertilization is required. These results indicate that the stamped soil and the health of soil can be restored, when replanting plants in bare areas, by adding plans to improve soil, such as designing drain ways around the planted areas, transporting soil for the 50 cm depth of the ground and mixing organic matters such as chaff, and simply by planting groundcover plants in the lower part of tress and shrubs.

An experimental study on diameter increase of orthodontic wire by electroplating (전기도금을 이용한 스테인레스 스틸 선재의 직경 증가에 관한 실험적 연구)

  • Cho, Jin-Hyoung;Sung, Young-Eun;Lee, Ki-Heon;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.33 no.2 s.97
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    • pp.121-130
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    • 2003
  • The purpose of this study was to evaluate the possibile clinical application of electroplating to increase diameter of an orthodontic wire, through examining the change of physical properties. The diameter of stainless steel orthodontic wire was increased from 0.016 inch to 0.018 inch by electroplating in a bath of nickel sulfate 100g/L, nickel chloride 60g/L, boric acid 30g/L, and sodium chloride 50g/L, under the conditions of 1.7V, $25\~29^{\circ}C\;and\;3.1\~3.3pH$. During the electroplating, the rate of diameter increase was measured every minute. To investigate uniformity, the diameter was measured at three different locations of each wire specimen aster electroplating. An X-ray diffraction test was performed to analyze the nature of the electroplated metal. Following heat treatment to improve adhesion between the wire and electroplated metal, a three-point bending test was conducted to compare stiffness, field strength, and ultimate strength among four wire groups; 0.016 inch, electroplated 016, electroplated and heat-treated 016, and 0.018 inch wires. Through the comparison of each wire group, following results were obtained. 1. In the load-deflection graph, the curve of the electroplated group was Placed between that of the 0.016 inch group and the 0.018 inch group, and the owe was closer to the 0.018 inch group by heat treatment. 2. In the electroplated and heat-treated 016 wire group, the values of stiffness, yield strength and ultimate strength showed higher tendency than in the original 0.016 Inch group. Stiffness and ultimate strength showed statistically significant differences between two groups. 3. Stiffness, yield strength, and ultimate strength of electroplated wire presented lower values than those of 0.018 inch wire group. 4. Stiffness, yield strength, and ultimate strength of electroplated and heat-treated wire showed higher tendency than those of electroplated wire group, and ultimate strength showed statistically significant difference between two groups. 5. After electroplating, the difference in diameter between the three locations was within $0.1\~0.3\%$ variation, and showed no statistical significance.

Characterization of Lactate Dehydrogenase in Acanthogobius hasta (풀망둑(Acanthogobius hasta) 젖산탈수소효소의 특성)

  • Yum, Jung-Joo
    • Journal of Life Science
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    • v.18 no.2
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    • pp.264-272
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    • 2008
  • The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Acanthogobius hasta were characterized by biochemical, immunochemical and kinetic methods. The activities of LDH in skeletal muscle and eye tissues were 65.30 and 53.25 units, but LDH activities in heart and liver tissues were very low. LDH/CS (EC 4.1.3.7, citrate synthase) in skeletal muscle was the highest as 22.29. Specific activities of LDH in brain, eye and skeletal muscle were 56.45, 38.04 and 11.0 units/mg, respectively. The LDH isozymes in tissues were separated by polyacrylamide gel electrophoresis after immunoprecipitation with antiserum against $A_4,\;B_4$ eye-specific $C_4$ and liver-specific $C_4$. LDH $AC_4$ isozymes were detected predominantly in skeletal muscle, brain and eye tissues, and $B_4$ isozyme was detected in heart. Anodal eye-specific $C_4$ and cathodal liver-specific $C_4$ were coexpressed in A. hasta. The eye-specific $C_4$ isozyme showed higher activity in eye tissue, but liver-specific $C_4$ isozyme showed lower activity in liver. As a result, one part of molecular structures in $A_4\;and\;C_4,\;A_4\;and\;B_4$, and eye-specific $C_4$ and liver-specific $C_4$ were similar, but in $B_4\;and\;C_4$ were different with each other. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The LDH $A_4$ isozyme of skeletal muscle was purified in the fraction from elution with NAD+ containing buffer of affinity chromatography and eye-specific $C_4$ isozyme was eluted right after $A_4$, so the structure of eye-specific $C_4$ isozyme is similar to $A_4$. And LDH activity remained 35.22-43.47% as a result of the inhibition by pyruvate, the Michaelis-Menten constant values for pyruvate was 0.080-0.098 mM, and Vmax were 153.85 units, 35.09 units in skeletal muscle and eye, respectively. Also the $B_4$ isozyme was the thermo-stablest and $C_4$ was stabler than $A_4$ isozyme. The optimum pH of LDH was 6.5. The results mentioned above indicate that isozymes in tissues showed the properties between LDH $A_4\;and\;B_4$ isozyme as A. hasta was adapted to hypoxic conditions. Also LDH seems to function more effectively under anaerobic condition because LDH in skeletal muscle and eye tissues have high affinity for pyruvate.

Saponin Content and Quality for the Promotion of White Ginseng Water Extraction Conditions (사포닌 함량 및 품질의 증진을 위한 백삼 물추출액 추출 조건)

  • Han, Jin-Soo;Li, Xiangguo;Park, Yong-Jun;Kang, Sun-Joo;Kim, Jung-Sun;Nam, Ki-Yeul;Lee, Ki-Teak;Choi, Jae-Eul
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.54 no.4
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    • pp.458-463
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    • 2009
  • In this study, white ginseng water extract (WGWE) solutions were analyzed to set up the functional saponin content and quality optimization condition. The highest saponin content among the total white ginseng extracts was 8.32 mg/10 ml which was extracted at $75^{\circ}C$ for 18 hours. In addition, the saponin content decreased according to the increased extraction temperature and time. The highest content of $Rb_2$ and Re was 0.89 mg/10 ml, 0.82 mg/10 ml at $75^{\circ}C$ for 18 hours which decreased according to the increased extracted temperature and time. The highest content of $Rg_3$ was 1.67 mg/10 ml at $95^{\circ}C$ for 24 hours which decreased according to the increased time. The turbidity, sweetness and reducing sugar content were increased according to the increased extracted time at $75^{\circ}C$, $85^{\circ}C$, $95^{\circ}C$, but pH were decreased according to the increased extracted time. Therefore, the most appropriate white ginseng extracting method have to extracted the proper temperature for saponin content at first time in combination with raise the temperature for taste at second time.

Production and Characterization of Extracellular Polysaccharide Produced by Pseudomonas sp. GP32 (Pseudomonas sp. GP32에 의해 생산된 세포 외 다당류의 생산 및 특성)

  • Lee, Myoung Eun;Lee, Hyun Don;Suh, Hyun-Hyo
    • Journal of Life Science
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    • v.25 no.9
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    • pp.1027-1035
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    • 2015
  • A strain GP32 which produces a highly viscous extracellular polysaccharide was conducted with soil samples and identified as Pseudomonas species. The culture flask conditions for the production of extracellular polysaccharide by Pseudomonas sp. GP32 were investigated. The most suitable carbon and nitrogen source for extracellular polysaccharide production were galactose and (NH4)2SO4. The optimum carbon/nitrogen ratio for the production of extracellular polysaccharide was around 50. The optimum pH and temperature for extracellular polysaccharide production was 7.5 and 32℃, respectively. In batch fermentation using a jar fermentor, the highest extracellular polysaccharide content (15.7 g/l) was obtained after 70 hr of cultivation. The extracellular polysaccharide produced by Pseudomonas sp. GP32 (designated Biopol32) was purified by ethanol precipitation, cetylpyridinium chloride (CPC) precipitation, and gel permeation chromatography. Biopol32, which has an estimated molecular weight of over 3×107 datons, is a novel polysaccharide derived from sugar components consisting of galactose, glucose, gulcouronic acid and galactouronic acid in an approximate molar ratio of 1.85 : 3.24 : 1.00 : 1.42. The solution of Biopol32 showed non-Newtonian characteristics. The viscosity of Biopol32 exhibited appeared to be higher at all concentration compared to that of zooglan from Zoogloea ramigera. An analysis of the flocculating efficiency of Biopol32 in industry wastewater (food, textile, and paper wastewater) revealed chemical oxygen demand (COD) reduction rates 58.4-67.3% and suspended solid (SS) removal rates 82.6-91.3%. Based on these results, Biopol32 is a possible candidate for industrial applications such as wastewater treatment.

Distribution and Favorable Conditions for Mycelial Growth of Cordyceps pruinosa in Korea (한국에 자생하는 붉은자루동충하초(Cordyceps pruinosa)의 분포와 균사생장에 적합한 조건)

  • Shin, Jae-Chul;Shrestha, Bhushan;Lee, Won-Ho;Park, Young-Jin;Kim, Soo-Young;Jeong, Gwang-Ryel;Kim, Ho-Kyung;Kim, Tae-Woong;Sung, Jae-Mo
    • The Korean Journal of Mycology
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    • v.32 no.2
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    • pp.79-88
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    • 2004
  • Cordyceps pruinosa grows upon dead pupae of Lepidoptera and produces one or $3{\sim}4$ club-shaped stromata per host. The stromata have distinct club-shaped head and long stalk. The length of stromata varies from $1{\sim}3\;cm$. Apical head consists of densely crowded semi-immersed perithecia, which are $360{\sim}400\;{\times}\;180{\sim}200\;{\mu}m$ in size. Asci are $150\;{\mu}m$ in length and $2.8{\sim}3\;{\mu}m$ in diameter. Ascospores, which are $124{\sim}141\;{\mu}m$ in length, have thin thread-like structures in the middle with part-spores attached on both sides. Each ascospore does not separate into part-spores after dispersal, but each part-spore germinates and together develops a colony. The imperfect form produces phialides of $15{\sim}24\;{\times}\;2{\sim}3\;{\mu}m$ size, with spherical or spindle shaped conidia of $4{\sim}6\;{\times}\;1.8{\sim}2.4\;{\mu}m$ size, The anamorph was identified as Mariannaea elegans Samson. YMA and SDAY agar media with pH 7 was produced abundant mycelial growth with high density. Best mycelial growth was observed when dextrin was used as a carbon source. Lactose, saccharose and sucrose also produced high mycelial growth. Peptone, yeast extract and tryptone produced abundant mycelial growth, when used as nitrogen sources. Highest mycelial growth and density was observed when C/N ratio was 1 : 1 at the concentration of 12.5 g/l each. $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial dry wt. was produced in YM and SDAY broths. Optimum inoculum for 100 ml of liquid broth was 6 mycelial discs. Similarly, optimum liquid culture period was 7 days.

Behaviour of the Soil Residues of the Acaricide-Insecticide, [$^{14}C$]Acrinathrin;II. Degradation in Soil (살비살충제 [$^{14}C$Acrinathrin 토양 잔류물의 행적 규명;II. 토양중 분해)

  • Lee, Jae-Koo;Kyung, Kee-Sung;Oh, Kyeong-Seok
    • Korean Journal of Environmental Agriculture
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    • v.14 no.2
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    • pp.202-212
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    • 1995
  • In order to elucidate the degrading characteristics of the pyrethroid acaricide-insecticide, acrinathrin in two different types of soils, Soil A(pH, 5.8; organic matter, 3.4%; C.E.C., 115 mmol(+)/kg soil; texture, sandy loam) and Soil B(pH, 5.7; organic matter, 2.0%; C.E.C., 71 mmol(+)/kg soil; texture, sandy loam), residualities of the non-labeled compound under the field and laboratory conditions, extractability with organic solvents and formation of non-extractable bound residues, and degradabilities of [$^{14}C$]acrinathrin as a function of aging temperature and aging period were investigated. The half lives of acrinathrin in Soil A treated once and twice were about 18 and 22 days and in Soil B about 13 and 15 days, respectively, in the field, whereas, in the laboratory, those in Soil A and B were about 36 and 18 days, respectively, suggesting that the compound would be non-persistent in the environment. The amounts of $^{14}CO_2$ evolved from [$^{14}C$]acrinathrin in Soil A and B during the aging period of 24 weeks were 81 and 62%, respectively, of the originally applied $^{14}C$ activity, and those of the non-extractable soil-bound residues of [$^{14}C$]acrinathrin were about 70% of the total $^{14}C$ activity remaining in both soils, increasing gradually with the aging period. Degradation of [$^{14}C$]acrinathrin in both soils increased with the aging temperature. Three degradation products of m/z 198(3-phenoxy benzaldehyde), m/z 214(3-phenoxybenzoic acid), and m/z 228(methyl 3-phenoxybenzoate) as well as an unknown were detected by autoradiography of acetone extracts of both soils treated with [$^{14}C$]acrinathrin and aged for 15, 30, 60, 90, 120, and 150 days, respectively, and the degradation pattern of acrinathrin was identical in both soils. Acrinathrin in soil turned out to be degraded to 3-phenoxybenzaldehyde cyanohydrin by hydrolytic cleavage of the ester linkage adjacent to the $^{14}C$ with a cyano group, the removal of hydrogen cyanide therefrom led to the formation of 3-phenoxybenzaldehyde as one of the major products, and the subsequent oxidation of the aldehyde to 3-phenoxybenzoic acid, followed by decarboxylation would lead to the evolution of $^{14}CO_2$.

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