• Title/Summary/Keyword: Water composition

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A Study on the Peak Separation of Acetone and Acrolein Based on High-Performance Liquid Chromatography (HPLC) Method

  • Kim, Shin-Do;Kim, Chang-Hwan;Park, Jin-Su;Lee, Jeong-Joo
    • Bulletin of the Korean Chemical Society
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    • v.30 no.9
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    • pp.2011-2016
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    • 2009
  • To resolve the differentiation problem of acetone and acrolein in the analysis of carbonyls by high-performance liquid chromatography (HPLC), we investigated the optimum analytical conditions for their separation. Carbonyl compounds were collected by 2,4-dinitrophenylhydrazine (DNPH)-coated cartridges. We examined the influence of three experimental variables: temperature (25, 30, 40, 50 and 60 ${^{\circ}C}$), flow rate (1.0 and 1.2 mL/min), and relative mobile phase composition (among acetonitrile, water and tetrahydrofuran). The experimental results revealed the optimum analytical condition of a flow rate of 1.2 mL/min, temperature of 32 ${^{\circ}C}$ and mobile phase composition of acetonitrile: water: tetrahydrofuran = 34 : 52.8 : 13.2. The analysis of indoor air composition indicated that acrolein and acetone comprised 11% and 42% of all aldehydes, respectively.

The Studies of Composition of Fatty Acids and Antioxidant Activities in Parts of Omija (Schizandra chinensis Baillon) (오미자의 부위에 따른 지방산 조성과 항산화 활성에 관한 연구)

  • Lee, Joung-Sook;Lee, Sung-Woo
    • Journal of the Korean Society of Food Culture
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    • v.6 no.2
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    • pp.147-153
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    • 1991
  • We have studies fatty acid composition of water extracts of parts of omija (Schizandra chinensis Baillon) and antioxidant activities of fractionated omija parts (fruits, endocarps, seeds) were determined by DPPH methods and by in vitro hepatic microsomal lipid peroxidation system. Fatty acid composition was not different by parts of omija and major fatty acids are linoleic, oleic, and palimitic acids, among fatty acids is water extracts of parts of omija, linoleic acid was highest in content. Methanol and buthanol fractions of seeds and ethyl acetate fraction of endocarps showed stronger antioxidant activities by DPPH methods. Methanol and buthanol fractions of seeds also showed on inhibitory effect on in vitro liver microsomal lipid peroxidation.

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A study of Association between Growth and Body Composition in Teenagers (청소년의 성장과 체성분과의 상관성에 관한 연구)

  • 홍상훈;김성환;강창완
    • The Journal of Korean Medicine
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    • v.22 no.4
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    • pp.114-120
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    • 2001
  • Objectives : Man adapts himself to nature, so accordingly as he grows up, changes of body composition appear. This study measured the changes of body compositions on the ground of Sasang constitution and seasons Methods : 253 middle school students who live in Busan were studied from the 20th of March, 1999 to the 20th of March, 2001. We measured height and body compositions with Inbody 3.0, six times during that period. Results : According as they grew up, total body water, muscle area, body weight, BMI (Body Mass Index), BMR (Basal Metabolic Rate), ACM (Arm Muscle Circumference), and BCM (Body Cell Mass) increased, but fat body weight ratio decreased. From March to June, total body water, muscle area, height, ACM, and BCM increased. From September to December fat body weight, fat body weight ratio, waist hip ratio increased as compared with other seasons. Height of Soyangin and BMI of both Soyangin and Taeumin increased more than those of other groups, with statistical significance Conclusions : The growth of man is adapting oneself to changes of nature, and it corresponds to the theory of (correspondence between man and universe).

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Seasonal Variation of Species Composition of fish by Otter Trawl in the Coastal Waters off Gijang, Busan, Korea (부산 기장 연안에서 저인망으로 어획된 어류 군집의 계절 변화)

  • Hwang, Choul-Hee;Park, Yun Jeong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.4
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    • pp.429-436
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    • 2017
  • The seasonal and interannual variations in fish assemblages in the coastal waters off Gijang were examined with an otter trawl from 2015 to 2016. A total of 59 fish species was collected during the study period. The dominant species were Caelorinchus multispinulosus, Clupea pallasii pallasii and Chelidonichthys spinosus. Seasonal changes in fish assemblages appeared to be distinct in the study area. The fish assemblages in summer and autumn were clearly distinguishable from those in other seasons, and the largest numbers of species and individuals were captured in winter and summer, respectively. Because fish assemblages are closely related to changes in water temperature, long-term changes in water temperature can have a significant impact on the productivity of offshore fisheries by changing fish species composition, habitat migration, and growth rate of fish.

A Study on THMs Formation in Drinking Underground Water at Kunsan (군산지역 음용지하수 트리할로메탄(THMs) 생성에 관한 연구)

  • 황갑수
    • Journal of Environmental Health Sciences
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    • v.26 no.4
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    • pp.122-128
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    • 2000
  • This study was carried out to survey trihalomethane formation potential(THMFP) levels in drinking underground water and to examine its characteristics in Kunsan area. In drinking underground water, THMFP increased with the lapse of reaction time and 96hr-THMFP was the highest of THMFPs examined. In many cases, 24hr-THMFP, 48hr-THMFP and 96hr-THMFP reflected 2hr-THMFP level due to the largest composition ratio of CHCl$_3$ decreased with the lapse of reaction of CHCl$_3$ among THM individuals. CHCl$_3$ was mostly formed within early 2hour of reaction time, but CHClBr$_2$ and CHBr$_3$ continued their formation until 48 hour. Accordingly, the composition ratio of CHCl$_3$ decreased with the lapse of reaction time while that of total Br derivatives increased. 96hr-THMFPs of drinking underground water in Kunsan area ranged from N.D.(not detected)~98.80 $\mu\textrm{g}$/$\ell$ and, in general, those of western section of Kunsan area, closer to the coast, showed the higher tendency. But, from their large range of variance, it could be considered that THMFPs differ individually even in the same section depending on such factors as the difference of water stream, circumstances of management and so on. All the parameters for water quality examined(pH, KMnO$_4$ consumption;UV$_{254}$ , TOC. Cl$^{[-10]}$ ) showed very week corelation with 96h-THMFP.

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Influence of Drought Stress on Chemical Composition of Sesame Seed

  • Kim, Kwan-Su;Ryu, Su-Noh;Chung, Hae-Gon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.1
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    • pp.73-80
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    • 2006
  • Sesame (Sesamum indicum L.) seeds contain abundant oil and antioxidative lignans related to the seed quality. To evaluate the potential effects of drought stress on the chemical composition of sesame seeds, eighteen cultivars were imposed water-deficit condition by withholding irrigation during 15 days at podding and maturing stage, compared with well-watered plants as control in seed yield and chemical composition. Drought treatments showed great decrease of seed yield with not affecting seed weight. The contents of sesamin and sesamolin decreased while lignan glycosides inversely increased in response to drought stress. Oil content was not significantly changed by drought treatment in spite of its slight decrease. In case of fatty acid composition, there were significant differences in increase of oleic acid while inverse decrease of linoleic acid under drought stress condition. These results demonstrate that the chemical composition of sesame seed may be modified with drought stress. In particular, the increase of sesaminol glucosides with strong antioxidative activity was observed.

Relationship between Vegetation Composition and Dissolved Nitrogen in Wetlands of Higashi-Hiroshima, West Japan

  • Miandoab, Azam Haidary;Nakane, Kaneyuki
    • Journal of Ecology and Environment
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    • v.30 no.3
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    • pp.209-223
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    • 2007
  • Twenty-four wetlands located in Higashi-Hiroshima City in West Japan were selected for this study in order to investigate both the relationship between aquatic plant composition and environmental conditions; and the relationship between changing land use patterns in the catchments and the concentration of different forms of nitrogen in the wetlands. The dominant and subdominant species which comprised the principal vegetation were determined based on a vegetation census conducted in each wetland during the growing season from June to August, 2006. The seasonal variations of water quality factors (pH, electrical conductivity, turbidity, dissolved oxygen, total dissolved solid, and temperature) and different forms of nitrogen such as nitrite, nitrate, ammonium, total nitrogen, dissolved organic nitrogen and dissolved inorganic nitrogen concentrations were analyzed as important indicators of water quality for the surface water of the wetlands. The surveyed wetlands were classified into three types (non-disturbed wetlands, moderately-disturbed wetlands and highly-disturbed wetlands), based on the degree of human disturbance to their catchment areas. An analysis of variance indicated that there was a significant difference among the wetland groups in the annual mean values of electrical conductivity, total dissolved solids, total nitrogen, nitrite, dissolved inorganic nitrogen and dissolved organic nitrogen. Classification of the wetlands into three groups has revealed a pattern of changes in the composition of plant species in the wetlands and a pattern of changes in nitrogen concentrations. A majority of the non-disturbed wetlands were characterized by Brasenia schrebi and Trapa bispinosa as dominant; with Potamogeton fryeri and Iris pesudacorus as sub-dominant species. For most of the moderately-disturbed wetlands, Brasenia schrebi were shown to be a dominant species; Elocheriss kuriguwai and Phragmites australis were observed as sub-dominant species. For a majority of the highly-disturbed wetlands, Typha latifolia and T. angustifolia were observed as dominant species, and Nymphea tetragona as the sub-dominant species in the study area. An analysis of land use and water quality factors indicated that forest area played a considerable role in reducing the concentration of nutrients, and can act as a sink for surface/subsurface nutrient inputs flowing into wetland water, anchor the soil, and lower erosion rates into wetlands.

Correlation Analysis of Sports injuries and Body Composition and Bone Density in National Water Pool Players (국가대표 수구선수들의 스포츠 손상과 신체 조성 및 골밀도의 상관관계 분석)

  • Kim, Hyun-Chul;Park, Ki-Jun
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.3
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    • pp.134-141
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    • 2019
  • PURPOSE: This study conducted aA forward-looking study of elite water polo athletes, who trained at National Training Center, was conducted to determine the correlation between the incidence of sports injuries and the bone density among national water polo players. METHODS: Data on the general characteristics of all study subjects were analyszed usingin descriptive statistics. The incidence of sports injuries was calculated from the incidence of sports injuries per 1,000 hours and the incidence of sports injuries resulting from exposure to 1,000 training sessions. The incidence of all sports injuries was calculated with a 95% confidence interval. Furthermore, Pearson's correlation was calculated conducted to determine the correlation between sports injuries and bone density, bone mass and body composition. RESULTS: Water polo athletes suffered a total of 127 sports injuries in the three-year period, while the athletes suffered 3.5 sports injuries each year. The Ooverall injury rate of 3.2(95% CI 2.68-3.81) per 1,000h, 18.0(15% CI 14.89-21.16) of sports injuries per 1,000AE. For all athletes, 50.4% of the injuries were classified as mild, followed by moderate (26.8%) and severe (22.8%). The lower the bone density in all areas of sports injuries, the higher the incidence of sports injuries. In addition, and the lower the bone mass in all areas except for light injuries, the higher the incidence of sports injuries. CONCLUSION: In tThe correlation between sports injuries and bone density and bone composition of water polo athletes, revealed a significant correlation between the bone density and bone mass were statistically significant, and the lower the bone density and bone mass, the higher the incidence of sports injuries.

Species composition and abundance of larval fishes in the coastal waters off Gori, Korea in 2006 (2006년 고리 주변해역에 출현하는 자치어의 종조성과 출현양상)

  • Baeck, Gun Wook;Park, Joo Myun;Nam, Ki Moon;Huh, Sung-Hoi
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.48 no.3
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    • pp.284-292
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    • 2012
  • Species composition and abundance of larval fishes in the coastal waters off Gori in the southeastern Korea were investigated from January to December in 2006. During the study period, 32 larvae species belonging to 20 families were collected. The dominant species were Engraulis japonicius, Hexagrammos agrammus, Sillago japonicus, Acropoma japonicum, Apogon lineatus, and Konosirus punctatus. These six species accounted for 87.0% of the total number of individuals collected. The number of species, number of individuals, and species diversity indices fluctuated by season. The peak numbers of species and individuals occurred in July and May, respectively. Correlation analysis showed that monthly variations in water temperature and salinity could act as an indicators of seasonal variations in the larval fish community structure and abundance of the dominant species; in particular, the abundance of S. japonicus, A. japonicum, and A. lineatus were significantly corrected with the water temperature.

The Effect of Composition of Flour Brew on Growth and Activity of Lactic Acid Bacteria (제빵에서 밀가루 Brew의 조성이 젖산균의 생육에 미치는 영향)

  • 조남지
    • The Korean Journal of Food And Nutrition
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    • v.11 no.6
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    • pp.683-688
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    • 1998
  • This study was conducted to develop optimal composition of flour brew in order to economically utilize flour brew inoculated by lactic acid bacteria as a starter(mother sponge) in bread-making. Two flour brews were prepared ; one with flour and water, the other with flour, water and NaCl. Various nutrients were added to both flour brews and Lactobacilli deMan Rogosa and Sharpe (MRS) broth to investigate the effect of them on growth and activities of Streptococcus thermophilus, Lactobacillus brevis and their mixed culture in flour brews to be tested with incubation at 37$^{\circ}C$. The growth of Streptococcus thermophilus, Lactobacillus brevis and their mixed culture was stimulated by addition of NaCl with 0.85% concentratin and more by mixed culture than by single lactic acid bacteria, resulting in 3 hrs reduction in cultivation and more by mixed culture than by single lactic acid bacteria, resulting in 3 hrs reduction in cultivation time. the addition of 3% glucose to flour brew with NaCl was observed to enhance acid productioni by mixed culture. Yeast extract greatly affected growth and activities of mixed culture of lactic acid bacteria in flour brew with NaCl and its optimum level of this additive in flour brew with NaCl was approximately 1.0%. The optimal composition of flour brew for mixed culture of lactic acid bacteria was suggested as follows; flour 100g, water 300g, NaCl 3.46g, glucose 12.48g, yeast extract 3.46g.

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