• Title/Summary/Keyword: 농도계

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Evaluation of the Genetic Toxicity of Synthetic Chemicals (Ⅶ) -A Synthetic Selective Herbicide, Pendimethalin- (합성화학물질들의 유전독성평가(Ⅶ) -합성 제초제인 Pendimethalin-)

  • Ryu, Jae-Chun;Kim, Kyung-Ran
    • Environmental Analysis Health and Toxicology
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    • v.18 no.2
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    • pp.121-129
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    • 2003
  • The genotoxicity of pendimethalin [N-(l-ethylpropyl)-2, 6-dinitro-3, 4-xylidine, C$\_$13/H$\_$19/N$_3$O$_4$, M.W.=281.3, CAS No. 40487-42-1], one of selective herbicide, was evaluated in bacterial gene mutation system, chromosome aberration in mammalian cell system and in vivo micronucleus assay with rodent. In bacterial gene mutation assay, pendimethalin revealed dose-dependent mutagenic potential in 313 ∼ 5,000 ${\mu}$g/plate of Salmonella typhimurium TA 98 and TA 1537 both in the absence and presence of S-9 metabolic activation system, and TA 100 only in the absence of S-9 mixture. In the TA 1535, slight increase of revertant was also observed in the presence of S-9 metabolic activation system. No mutagenic potential was observed in the TA 1535 without metabolic activation system and TA l00 in the presence of S-9 mixture. In mammalian cell system using Chinese hamster lung (CHL) fibroblast, no clastogenicity of pendimethalin was observed both in the absence and presence of S-9 metabolic activation system in the concentration range of 2.32∼9.28 ${\mu}$g/ml. And also, in vivo bone marrow micronucleus assay, pendimethalin revealed no clastogenic potential in the dose range of 203∼810 mg/kg body weight after oral administration in mice. Consequently, in vitro chromosome aberration with mammalian cells and in vivo bone marrow micronucleus assay revealed no clastogenic potential of pendimethalin. However, pendimethalin revealed mutagenic potential in bacterial gene mutation assay.

A Study on the Toxicity Assessment of Plating Wastewater using Aquatic Microcosm (수계 Microcosm을 이용한 도금폐수의 독성평가)

  • 위성욱;도삼유평;조경;나명석;이종빈
    • Korean Journal of Environmental Biology
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    • v.20 no.3
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    • pp.256-262
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    • 2002
  • This research investigated experimentally on the population growth in the aquatic microcosm with the wastewater of plating factory. The purpose of this study was to evaluate the effect of culture conditions of the characteristic growth pattern of the examined species. Population of the system is consists of three organisms; Chlorella vulgaris as a producer, Cyclidium glaucoma as a consumer and Pseudomonas putida as a decomposer. The different growth patterns of each population are followed by surfactant type; Especially C. glaucoma was sensitive, Ch. uvlgaris was maintained population size stably even at high level of surfactant and p. putida was not significantly affected. After treatment of waste water from plating factory, it began to be affected at 1.0% solution treatment to Ch. vulgaris which the cell number was decreased prominently after 2 days, and C. glaucoma was disappeared at 2.5% solution treatment. P. putida was showed increasing pattern according to treatment concentration, at 2.5% solution and population size grew double. The result from current microcosm study indicates that this model system can be applied to environmental assessment method for various pollutants.

Biological activity of supercritical extraction residue 60% ethanolic extracts from Ulmus davidiana (느릅나무 초임계 추출박 60% 주정추출물의 생리활성)

  • Mun, Myung-Jae;Park, Kwang-Hyun;Choi, Sun Eun
    • Journal of Convergence for Information Technology
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    • v.8 no.5
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    • pp.29-36
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    • 2018
  • Ulmus davidiana supercritical fluid residue EtOH extracts(USCFR) and ethyl acetate solvent fraction (USCFREA) of supercritical extraction foil were investigated in order to examine the recycling of supercritical extraction foil in the process of studying Ulmus davidiana branch supercritical extract. Experiments were performed for the determination of total phenol content. The $IC_{50}$ value(ppm) of DPPH radical scavenging activity and ABTS radical scavenging activity was $7.42{\pm}0.09$, $7.50{\pm}0.05$, $22.94{\pm}0.09$, $6.43{\pm}0.10$, and USCFREA, respectively, as compared with the positive control (vitamin C) with values $17.80{\pm}0.14$ and $5.34{\pm}0.06$, respectively. The antioxidative activities of USCFR and USCFREA were confirmed to be superior to the positive control group. In anti-allergic activity studies, both USCFR and USCFREA showed concentration-dependentanti-allergic activity, and USCFREA showed strong anti-allergic activity even at very low concentrations. Thetotal phenolic contents (ugEG, ugGA; ppm) of USCFR were $134.17{\pm}0.13$, $132.02{\pm}0.24$ and USCFREA were $154.77{\pm}1.05$ and $153.18{\pm}1.10$, respectively. Based on the above results and strong antioxidant activity, USCFR and USCFREA hold the potential to be considered as basic research materials for the development of therapeutic supplements based medicines or functional cosmetics related to chronic inflammatory skin immunity diseases.

A Green Preparation of Drug Loaded PAc-β-CD Nanoparticles from Supercritical Fluid (초임계 유체를 이용한 약물이 담지된 PAc-β-CD 나노 입자의 친환경적인 제조)

  • Jang, Min Ki;Kim, Yong Hun;Kim, Dong Woo;Lee, Si Yun;Lim, Kwon Taek
    • Clean Technology
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    • v.26 no.1
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    • pp.1-6
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    • 2020
  • Rapid expansion of supercritical solution (RESS) process was used to make molsidomine (MOL) loaded peracetyl-β-cyclodextrin (PAc-β-CD) nanoparticles, which were collected into the air. The effect of the concentration of the drug PAc-β-CD (0.5 and 1 wt%), extraction temperature (45 ~ 60 ℃), nozzle length (5 ~ 20 mm) and internal diameter (ID) (50 ~ 150 μm) of a capillary, and spray distance on the particle size and morphology of the resulting particles were investigated. The interaction of a drug and PAc-β-CD was confirmed by 1H-NMR spectroscopy while the particle size was measured by means of a scanning electron microscope. It was found that increasing the temperature from 45 ℃ to 60 ℃ and decreasing the nozzle diameter from 150 μm to 50 μm had an increasing effect on the average particle size, while increasing the spray distance led to a decrease in the average particle size at a constant pressure of 34.5 MPa and temperature of 45 ℃. With 0.5 wt% of PAc-β-CD, the capillary nozzle of short length (5 mm) and small ID (50 μm) gave the smallest size (165 nm). The obtained nanoparticles showed increased dispersity and solubility in oil. The oil suspension of the inclusion complex showed increased sustainability, which can increase the in-vitro controlled release time of the drug.

Optimization of Ammonia Percolation Process for Ethanol Production from Miscanthus Sinensis (억새를 이용한 바이오 에탄올 생산을 위한 암모니아 침출 공정 최적화)

  • Kim, Kyoung-Seob;Kim, Jun Seok
    • Korean Chemical Engineering Research
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    • v.48 no.6
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    • pp.704-711
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    • 2010
  • Lignocellulose ($2^{nd}$ generation) is difficult to hydrolyze due to the presence of lignin and the technology developed for cellulose fermentation to ethanol is not yet economically viable. However, recent advances in the extremely new field of biotechnology for the ethanol production are making it possible to use of agriculture residuals and nonedible crops biomass, e.q., rice straw and miscanthus sinensis, because of their several superior aspects as agriculture residual and nonedible crops biomass; low lignin, high contents of carbohydrates. In this article, as the basic study of AP(Ammonia Percolation), the properties and the optium conditions of process were established, and then the overall efficiency of AP was investigated. The important independent variables for AP process were selected as ammonia concentration, reaction temperature, and reaction time. The percolation condition for maximizing the content of cellulose, the enzymatic digestibility, and the lignin removal was optimized using RSM(Response Surface Methodology). The determined optimum condition is ammonia concentration; 11.27%, reaction temperature; $157.75^{\circ}C$, and reaction time; 10.01 min. The satisfying results were obtained under this optimized condition, that is, the results are as follows: cellulose content(relative); 39.98%, lignin content(relative); 8.01%, and enzymatic digestibility; 85.89%.

Whole-genome Transcriptional Responses to Hypoxia in Respiration-proficient and Respiration-deficient Yeasts: Implication of the Mitochondrial Respiratory Chain in Oxygen-regulated Gene Expression (저산소 환경에 대한 전체 유전자 발현 반응에서 미토콘드리아 호흡계의 연루)

  • Lee, Bo Young;Lee, Jong-Hwan;Byun, June-Ho;Woo, Dong Kyun
    • Journal of Life Science
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    • v.26 no.10
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    • pp.1137-1152
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    • 2016
  • Cells sense, respond, and adapt to a low oxygen environment called hypoxia, which is widely involved in a variety of human diseases. Adaptation to low oxygen concentrations includes gene expression changes by inducing hypoxic genes and reducing aerobic genes. Recently, the mitochondrial respiratory chain has been implicated in the control of these oxygen-regulated genes when cells experience hypoxia. In order to obtain an insight into an effect of the mitochondrial respiratory chain on cellular response to hyxpoxia, we here examined whole genome transcript signatures of respiration-proficient and respiration-deficient budding yeasts exposed to hypoxia using DNA microarrays. By comparing whole transcriptomes to hypoxia in respiration-proficient and respiration-deficient yeasts, we found that there are several classes of oxygen-regulated genes. Some of them require the mitochondrial respiratory chain for their expression under hypoxia while others do not. We found that the majority of hypoxic genes and aerobic genes need the mitochondrial respiratory chain for their expression under hypoxia. However, we also found that there are some hypoxic and aerobic genes whose expression under hypoxia is independent of the mitochondrial respiratory chain. These results indicate a key involvement of the mitochondrial respiratory chain in oxygen-regulated gene expression and multiple mechanisms for controlling oxygen-regulated gene expression. In addition, we provided gene ontology analyses and computational promoter analyses for hypoxic genes identified in the study. Together with differentially regulated genes under hypoxia, these post-analysis data will be useful resources for understanding the biology of response to hypoxia.

Characteristics and long term variation trend of water mass in the coastal part of East Sea, Korea (동해연안 수괴의 특성과 장기변동 추이)

  • Yoon, Yi-Yong;Jung, So-Jung;Yoon, Sang-Chul
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.1
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    • pp.59-65
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    • 2007
  • Rapid variation of coastal ecosystem in the East Sea of Korea, such as fishery resource variation and subtropical chang of bentic flora, accordong to the global warming are actually noticed. In this study we try to identify the characterics of water mass existing in this coastal area and to consider the variation of their physical and chemical properties using data of temperature, salinity and dissolved oxygen obtained by National Fisheries Research & Development Institute from 1960 to 2005. The temperature of all water mass rise during last 45 years; the rise of North Korea Cold Water temperature (about $2.33^{\circ}C$) is 1.5 times higher than that of Tsushima warm water (about $1.6^{\circ}C$), and the temperature rise of Tsushima Surface Water, directly affected by climate chang is $2.57^{\circ}C$, higher than the atmospheric temperature rise during same period, indicating that subtropical change makes progress more rapidly in the coastal marine ecosystem than in the land ecosystem. Otherwise, the salinity in the surface water decrease $0.29\%_{\circ}$ during last 45 years due to the rising trend of rainfall with atmospheric temperature. The dissolved oxygen concentration in the all water mass make a decreasing trend. Specially for the North Korea Cold Water, the dissolved oxygen concentration diminish 0.021 mg/l per year and the decrease in the East Sea Proper Water indicate a change of inner water circulation system.

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Preparation and Properties of Geopolymer for Cultural Asset Restoration (문화재 복원용 무기계 수지의 합성 및 특성)

  • Hwang, Yeon;Hwang, Sun-Do;Kang, Dae-Sik;Park, Mi-Hye
    • Journal of Conservation Science
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    • v.25 no.1
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    • pp.17-24
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    • 2009
  • The feasibility of the geopolymer as a cultural asset restoration material was studied by investigating compressive strength and chromaticity change. Metakaolin that was synthesized by calcination of the kaolin at $750^{\circ}C$ for 6 hours was used as a geopolymeric starting material. Kaolin lost its crystallinity and changed into non-crystalline phase during calcination. NaOH solution and water glass were used as an initiator for the geopolymeric reaction. As the concentration of NaOH solution and water glass increased the compressive strength increased. When alumina was substituted with metakaolin, the compressive strength decreased at a small amount of alumina, but increased at a large substitution. For the most composition of geopolymers, the change of chroma values remained within the limit of slight variation after exposure to sunlight for 8 and 100 days. However, even small amount of organic pigment addition increased chroma values of metakaoline. It was shown that geopolymer had excellent chroma value change over epoxy resins.

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Research on Quantity and Characteristics of Excreta Produced by Laying Hen (산란계에 있어서 계분의 배설량과 이화학적 특성에 관한 연구)

  • 최희철;이덕수;강희설;곽정훈;최동윤;한정대;김형호
    • Journal of Animal Environmental Science
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    • v.7 no.1
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    • pp.39-44
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    • 2001
  • This research was carried out to determine the quantity and characteristics of layer excreta produced in different age and different types of layer house. Daily feed intakes in the growing stage were 60.8 and 92.9g/d the 6th and 12th week of age, respectively. Daily feed intakes in the early laying stage (19th wk of age) and the ending period of laying(55th wk of age) were 105.1 and 122.0 g/d, respectively. A laying hen consumed 193.1~222.5$m\ell$ of water per day. The amount of excreta produced by laying hen were 143.3~144.8g per day. The moisture contents of excreta produced by laying hen ranged over 74.7~80.5% in laying period. The average contents of N, $P_2O_5$ and $K_2O$ in layer excreta were 4.88, 1.92 and 1.71% in DM basis, respectively. In the laying period, CaO contents of excreta were 7.42~9.02%. The moisture contents of excreta produced by windowless poultry house, open-sided poultry house applied mechanical ventilation and open-sided poultry house applied natural ventilation were 65.4, 75.7 and 81.3% in summer, respectively.

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A Study on Anti-oxidant and Anti-wrinkle Effect of Supercritical Fluid Extraction of Black Carrot as a Functional Cosmetic Material (기능성화장품소재로서 자색당근 초임계추출물의 항산화 및 항주름 효능 연구)

  • Kim, Ji-Su;Lee, Ji-An
    • Journal of Convergence for Information Technology
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    • v.11 no.12
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    • pp.236-243
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    • 2021
  • The aim of this study was to evaluate the anti-oxidant and anti-wrinkle effect of the black carrot(BC) extracted by supercritical dioxide(SC-CO2). DPPH/ABTS radical scavenging and total polyphenol contents were measured to investigate the anti-oxidant activity of the BC supercritical extract. Collagen production and MMP-1 expression were assessed in normal human dermal fibroblasts(NHDF) for anti-wrinkle activity, The black carrot extract showed the highest total phenolic content(9.037±1.123 mg GAE/g extract) and the best antioxidant properties as shown by DPPH and ABTS assay. The supercritical fluid extracts of black carrot exhibited low toxicity to NHDF cells. In addition, the supercritical fluid extracts showed MMP-1 inhibition and type I pro-collagen synthesis inducing activities in a dose-dependent manner, respectively. Therefore, these results suggest that the black carrot is a potential source of high anti-oxidative, solvent-free and anti-aging material with promising applications in cosmetic, food, and beauty-food industries.