• Journal of the Korean Society of Safety
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• v.10 no.3
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• pp.68-80
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• 1995

A series of parametric calculations have been performed in order to investigate the short-term and short-range plume and puff behavior of toxic gaseous and solid pollutant dispersion in an open atmosphere. The simulation is made by the use of the computer program developed by this laboratory, in which a control-volume based finite-difference method is used together with the SIMPLEC algorithm for the resolution of the pressure-velocity coupling appeared In Wavier-Stokes equation. The Reynolds stresses are solved by the standard two-equation k-$\varepsilon$ model modified for buoyancy together with the RNG(Renormalization Group) k-$\varepsilon$ model. The major parameters considered in this calculation are pollutant gas density and temperature, the relative velocity of pollutants to that of the surrounding atmospheric air, and particulate size and density together with the height released. The flow field is typically characterized by the formation of a strong recirculation region for the case of the low density gases such as $CH_4$ and air due to the strong buoyancy, while the flow is simply declining pattern toward the downstream ground for the case of heavy molecule like the $CH_2C1_2$and $CCl_4$, even for the high temperature, $200^{\circ}C$. The effect of gas temperature and velocity on the flow field together with the particle trajectory are presented and discussed in detail. In general, the results are physically acceptable and consistent.

• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.49-58
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• 2006

Recently, geosynthetic clay liners (GCLs) have increasingly been used to replace compacted clay liners (CCLs) in composite liner systems. Since the introduction of GCLs to waste containment facilities, one of the major concerns about their use has been the hydraulic equivalency to CCLs as required by regulations. Laboratory test results and more recently field observations show that the thickness, or mass per unit area, of hydrated bentonite in a GCL can decrease under normal stress, especially around zones of stress concentration or nonuniform stresses, such as a rock or roughness in the subgrade, a leachate sump, or wrinkles in an overlying geomembrane. This paper presents field case histories that confirm the laboratory observations of bentonite migration and the effect of bentonite migration on hydraulic equivalency and contaminant transport through a GCL.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1991.05a
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• pp.8-12
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• 1991

Biodegradation of carbon tetrachloride (CTC) in denitrifying and aerobic columns was investigated under various conditions of electron-acceptor and electron-donor availability. CTC removal increased when the electron-acceptor (nitrate) injection was stopped in the denitrifying column ; however, CTC removal decreased when electron donor (acetate) was deleted in the denitrifying and the aerobic column. Small fractions of the CTC removed appeared as chloroform, indicating that reductive dechlorination of CTC was occurring. The results from the denitrifying column support the hypothesis that CTC behave as an electron acceptor that competes for the pool of available electrons inside the bacterial cells.

• Korean Journal of Pharmacognosy
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• v.20 no.3
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• pp.196-203
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• 1989

Experimental studies were conducted to investigate the effect of Sagan-Tang on analgesic, sedative, antipyretic, isolated ileum and blood vessel and so on. The results of this investigation were summarized as follows; Analgesic action by the acetic acid stimulating method in mice were recognized. Prolonging action against the hypnotic duration induced by thiopental-Na was noted in mice. Antipyretic effect in typhoid vaccine febrile rats was recognized. Spontaneous motility of the isolated ileum of mice was suppressed and contractions of the isolated ileum of mice and guinea-pig induced by accetylcholine chloride, barium chloride and histamine were remarkably inhibited. Vaso-diating and hypotensive actions were recognized in rabbits. GOT and GPT activities in the serum of rats damaged by $CCl_4$ and galactosamine were decreased remarkably.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.508-510
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• 2005

The crude extract of Quintinia acutifolia Kirk inhibited the growth of the Gram positive bacterium Bacillus subtilis ATCC 19659, (3 mm inhibition zone at $150\;{\mu}g/disc$) and the dermatophytic fungus Trichophyton mentagrophytes ATCC 28185, (3 mm inhibition zone at $150\;{\mu}g/disc$), and cytotoxic to P388 murine leukaemia cells ATCC CCL 46 P388D1, ($IC_{50}$ $50,000\;{\mu}g/mL$ at $150\;{\mu}g/disc$). However, Candida albicans (ATCC 14053) did not observed the antimicrobial activity and the cytotoxic activity to BSC monkey kidney cells ($({\alpha})$ 5 mg/mL, $150\;{\mu}g/disc$).

• Toxicological Research
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• v.26 no.2
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• pp.117-121
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• 2010

The crude ethanol extract of B. repanda showed the cytotoxic activity against Polio virus (25% activity at $150{\mu}g$/disk) and the minor cytotoxic activity against BSC cells (African green monkey kidney). However, the crude ethanol extract of B. repanda was non-toxic to murine leukaemia cells CCL 46 P388D1 ($IC_{50}$, > 62,500 ng/ml). Cytotoxic and antifungal activities were strongly shown by Fr. 64-3 which was eluted with 90% $CH_3CN/H_2O$, 100% $CH_3CN$, and 50% $CH_3CN/H_2O$(SM 2 at $150{\mu}g$/disk). The fraction 64-3 also showed the most cytotoxic activity against murine leukaemia cells (128 mg, $IC_{50}$ 10,051 ng/ml at $75{\mu}g$/disk). These results suggest that this fraction has a potent antifungal activity against the dermatophytic fungus Trichophyton mentagrophytes ATCC 28185.

• Biomolecules & Therapeutics
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• v.3 no.4
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• pp.245-250
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• 1995

The carbon tetrachloride($CCl_4$) has been demonstrated to have a hepatotoxic effect in human or many other species. To investigate the enzyme induction of mixed function oxygenases in liver of male Sprague-Dawley rats a single 0.1, 0.5 mι/kg dose of carbon tetrachloride were given. At 24 hr after a single dose of 0.1 mι CC1$_4$/kg weight, methanol extract of Hedera rhombea leaves was administered with 100, 500 mg/kg weight. Assays of 7-ethoxyresorufin-Ο-deethylation(EROD),7-benzyloxyresorufin-Ο-deathylation(BROD),4-nitro-phenol-UDP-glucuronosyltransferase(UDPGT), Western blot and RNA slot blot were used as representatives of the activities of cytochrome P-450 enzymes. The change of the activity of CYP1A1 form measured by EROD assay and Western analysis using 1-7-1 monoclonal antibody was not observed. The activity CYP2B1 form by BROD assay and using 2-66-3 monoclonal antibody was remarkably increased. Elevated level of CYP2B1 mRNA was shown by slot hybridization with 2B1-specific probe. Administration of methanol extract of Hedera rhombea leaves reversed the enzyme activity and the level of mRNA, which suggest the chemoprotective effect of methanol extracts of Hedera rhombea leaves to carbon tetrachloride hepatotoxlcity.

• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.372-376
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• 1987

Acetone solution of quinoline-8-carbaldehyde reacts with $[Rh(cod)(PPh_3)_2] PF_6$and $[Ir(cod)(PPh_3)_2] PF_6$ to yield $[Rh(NC_9H_6CO)(H)(PPh_3)_2(CH_3COCH_3)] PF_6$ (1) and $[Ir(NC_9H_6CO)(H)(PPh_3)_2(CH_3COCH_3)] PF_6$ (2), respectively. The compound $[Ir(cod)(PPh_3)_2] PF_6$ also reacts with $Ph_2PC_6H_4-o-CHO$ in the acetone / $H_2O$ mixture to give $[Ir(Ph_2PC_6H_4-o-CO)(H)(PPh_3)_2(CH_3COCH_3)] PF_6$ (3). Compounds 1, 2, and 3 were characterized by infrared, $^1H$ NMR, $^{31}P$ NMR spectra and conductivity measurement. The $^1H$ NMR spectra of 1, 2, and 3 support the presence of a terminal hydride that is cis to the phosphine. The IR band of 3 at 2185 $cm^{-1}$, which is assigned to $\nu$(Ir-H), and the hydride cleavage reaction of 3 with $CCl_4$, provide evidence for the Ir-H bond.

• Computers and Concrete
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• v.22 no.6
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• pp.551-561
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• 2018

The percolation of interfacial transition zone (ITZ) in cementitious materials is of great importance to the transport properties and durability issues. This paper presents numerical simulation research on the ITZ percolation threshold of mortar specimens at meso-scale. To simulate the meso-scale model of mortar as realistically as possible, the aggregates are simplified as ellipsoids with arbitrary orientations. Major and minor aspect ratios are defined to represent the global shape characteristics of aggregates. Some algorithms such as the burning algorithm, Dijkstra's algorithm and Connected-Component Labeling (CCL) algorithm are adopted for identification of connected ITZ clusters and percolation detection. The effects of gradation and aspect ratios of aggregates on ITZ percolation threshold are quantitatively studied. The results show that (1) the ITZ percolation threshold is mainly affected by the specific surface area (SSA) of aggregates and shows a global decreasing tendency with an increasing SSA; (2) elongated ellipsoidal particles can effectively bridge isolated ITZ clusters and thus lower the ITZ percolation threshold; (3) as ITZ volume fraction increases, the bridging effect of elongated particles will be less significant, and has only a minor effect on ITZ percolation threshold; (4) it is the ITZ connectivity that is essentially responsible for ITZ percolation threshold, while other factors such as SSA and ITZ volume fraction are only the superficial reasons.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.668-671
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• 2014

Wiress high-speed internet network and Mobile devices such as smartphones and tablets are popular, production and consumption of information is changing from the PC environment to mobile environment. Thus, the development of related programs in the development of mobile applications than PC is dramatically increasing. In particular, A tool that is very easy to manufacture mobile app are emergence, Professionals, as well as increasing the public's interest. In this paper, when create a moblie apps, copyright and software license to be considered are examined.