• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.65-72
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• 2003

In order to clarify turbulent combustion characteristics of hydrocarbon mixtures by hydrogen addition, turbulent burning velocities in a constant volume vessel were measured for both lean and rich hydrocarbon mixtures. Moreover, the configuration characteristics of turbulent flame was investigated in the wrinkled laminar flame region. A laser tomography technique was used to obtain the images of turbulent flame, and quantitative analyses were performed. As a result, the characteristics of turbulent burning velocity was shown a distinct difference with the addition rate of hydrogen between lean and rich mixtures. On the other hand, the obtained tomograms showed that the surface area of turbulent flame depends almost only on the turbulence intensity.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.32-43
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• 1997

Abstract A series of permeability tests was performed on the mixtures with specific mixing rates of sand and bentonite using modified rigid-wall permeameter. Sand-bentonite mixtures were permeated by organics, ethanol and TCE. Permeability of bentonite with several mixing rates had a tendency to decrease up to initial one pore volume and permeability was thereafter converged to a constant value. When sand-bentonite mixtures was permeated by water, permeability was decreased at the beginning but it was thereafter converged to a constant. Among several mixing rates, permeability was greatly decreased at 15% of mixing rate. When sand-bentonite mixtures with 15% mixing rate was permeated by ethanol, permeability was about 10 times larger value than permeability of water. Peameability was shown greater values when permeated by TCE (TrichloroEthylene) followed by ethanol. Suitable mixing rate of sand-bentonite for a liner of waste landfills was detected.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.146-150
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• 2010

Distribution Function and Drift velocities for electrons in $SF_6$-Ar mixtures gases used by MCS-BEq algorithm has been analysed over the E/N range 30~300[Td] by a two term Boltzmann equation and by a Monte Carlo simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight method. The results obtained in this work will provide valuable information on the fundamental behaviors of electrons in weakly ionized gases and the role of electron attachment in the choice of better gases and unitary gas dielectrics or electro negative components in dielectric gas mixtures. The results show that the deduced electron drift velocities agree reasonably well with theoretical for a rang of E/N values.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.455-462
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• 2016

The electron transport coefficients in not only pure atoms and molecules but also in the binary gas mixtures are necessary, especially on understanding quantitatively plasma phenomena and ionized gases. Electron transport coefficients (electron drift velocity, density-normalized longitudinal diffusion coefficient, and density-normalized effective ionization coefficient) in binary mixtures of TEOS gas with buffer gases such as Kr, Xe, He, and Ne gases, therefore, was analyzed and calculated by a two-term approximation of the Boltzmann equation in the E/N range (ratio of the electric field E to the neutral number density N) of 0.1 - 1000 Td (1 Td = 10⁻¹⁷ V.cm²). These binary gas mixtures can be considered to use as the silicon sources in many industrial applications depending on mixture ratio and particular application of gas, especially on plasma assisted thin-film deposition.

• Journal of Information Display
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• v.6 no.3
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• pp.1-5
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• 2005

The recent Bistable Nematic ($BiNem^{(R)}$) LCD technology presents long term bistability, high level passive matrix multiplexing, gray levels capabilities and high optical quality. The $BiNem^{(R)}$ device, based on anchoring breaking, needs specific low anchoring strength materials - alignment layers and liquid crystal mixtures. We present here our approach to develop nematic mixtures with wide enough temperature range and low zenithal anchoring energy.

• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.17-21
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• 2000

A Study on the electron energy distribution function in $SF_6+Ar$ mixtures gas used by MCS-BE algorithm, the electron swam parameters in the 0.5% and 0.2% $SF_6+Ar$ mixtures are measured by time of flight method over the E/N(Td) range from 30 to 300(Td). A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. The electron energy distribution function has been analysed in $SF_6$ gas and $SF_6+Ar$ mixtures at E/N : 200(Td) for a case of the equilibrium region in the mean electron energy. The measured results and the calculated results have been compared each other.

• Archives of Pharmacal Research
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• v.9 no.1
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• pp.55-61
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• 1986

To increase the dissolution rate of piroxicam, chitin and chitosan which are widely occurring biodegradable natural materials were used as drug carriers. The ground mixtures of piroxicam with chitin or chitosan were prepared by grinding in a ball mill. The dissolution rates of piroxicam from the ground mixtures were enhanced markedly than that from the physical mixtures or from intact piroxicam. The X-ray diffraction peaks disappeared in the ground mixture indicating the production of the amorphous form. The comparison of infrared spectra of the physical mixture and the ground minture showed an interaction such as association between the functional groups of piroxicam and chitin or chitosan in the molecular level. The weight losses in TGA curves shoed all the same patterns. However, in the ground mixture by DTA curve, the undothermic peak due to the fusion of piroxicam was disappeared indicating the different thermal property.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.3
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• pp.1-9
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• 2001

In this study, condensation heat transfer coefficients (HTCs) of nonazeotropic refrigerant mixtures of HFC32/HFC 134a and HCFC123 at various compositions were measured on a horizontal smooth tube. All data were taken at the vapor temperature of 39$^{\circ}C$ with a wall subcooling of 3~8K. Test results showed that HTCs of tested mixtures were 11.0~85.0% lowed than the ideal values calculated by the mass fraction weighting of the HTCs of the pure components. Thermal resistance due to the diffusion vapor film was partly responsible for the significant reduction of HTCs with these nonazeotropic mixtures. The measured data were compared against thc predicted ones by Colburn and Drew's film model and a good agreement was observed within a deviation of 15%.

• Journal of Plant Biology
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• v.19 no.4
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• pp.95-99
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• 1976

This work deals with different extraction media and reaction mixtures on photosystem II activity of Spinach chloroplasts. The photoreduction rate of ferricyanide and DPIP by intact chloroplasts which extracted with four kinds of extraction media; S-Tris-N pH 7.2, 8.0, S-Tricine-N pH 7.2, 8.0, was measured in five kinds of reaction mixtures; S-Tris-N pH 7.2, 8.0, S-Tricine-N pH 7.2, 8.0, 0.05 M-Tris pH 7.2. The extraction medium which shows the highest photoreduction rate was S-Tris-N at pH 7.2 and S-Tricine-N at pH 8.0. As to the reaciton mixture, S-Tricine-N pH 8.0 showed the highest rate. On the complex effects of extraction media and reaction mixtures, the highest photordeuction rate of Hill oxidant by intact chloroplasts was obtained by S-Tris-N pH 7.2 extraction medium and S-Tricine-N pH 8.0 reaction mixture. The second highest activity was obtained by S-Tricine-N pH 8.0 extraction medium and reaction mixture.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.11-16
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• 2005

Chemical mixtures of components, each of which are present at less than guidance concentrations, may be hazardous due to additivity, interactions, or both. Toxicological interactions may increase the health hazard above what would be expected from an assessment of each component singly, or all components additively. So chemical mixture are a particular issue in public health. There are several approach to assess whether there are additivity or interaction in assessing toxicological effects, such as, components-based approach, physiologically-based pharmacokinetic /pharmacodynamic(PBPK/PD) models, hazard index method, and weight-of evidence method. If we consider interaction or additivity effects in assessing the health effects of chemcial mixtures, we can get more accurate information about toxicological effects and dose-response relationship in chemical mixtures.