• International Journal of Aeronautical and Space Sciences
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• v.11 no.2
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• pp.59-68
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• 2010

The aim of this work is to analyze high temperature flows around an axisymmetric blunt body taking into account chemical and vibrational non-equilibrium state for air mixture species. For this purpose, a finite volume methodology is employed to determine the supersonic flow parameters around the axisymmetric blunt body. This allows the capture of a shock wave before a blunt body placed in supersonic free stream. The numerical technique uses the flux vector splitting method of Van Leer. Here, adequate time stepping parameters, along with Courant, Friedrich, Lewis coefficient and mesh size level are selected to ensure numerical convergence, sought with an order of $10^{-8}$.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.529-532
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• 1999

A five-year-old elk (Cervus canadensis) was presented for necropsy to the Veterinary Teaching Hospital, Chungbuk National University, on May 1999. The farmed elk was died on day 5 after velvet antler removal. By history taking, the elk didn't show any clinical signs except for watery diarrhea during 2 days. For the purpose of physical examination at the velvet antler removal, blood was collected from the femoral vein of elk with a mixture of fentanyl-azaperone-xylazine ($Fentazin-10^{\circledR}$). Urine was collected from the bladder within 3 hours after died. Hemato-logical and clincochemical values of the elk showed normal ranges. In the microscopic finding, many round and ellipse sarcocystis were identified in the cardiac muscle fibers without any surrounding inflammatory reaction.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.3
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• pp.302-310
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• 1997

In this paper, we find a method to improve ignitability using methanol which is prospective as an alternative fuel. The constant volume combuster is divided into main chamber and sub-cham¬ber. These two chambers are linked by an adapter which is shaped like a cup. We also compare CDI to HIS that is revised in our laboratory for making a scrutiny into the effects of ignition char¬acteristics. Besides, we analyze a flame propagation process in the main and sub-chamber through taking pictures 10, 000 frames per second by high speed camera at the state being fabricated quartz glass aside main and sub-chamber.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.727-729
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• 2001

The air separation of PET (Polyethylene terephthalate) and PS(Polystyrene) was carried out by taking advantage of the different abrasive resistance of two plastics. PET bottles and PS packages were shredded to small square pieces $(5{\times}5mm)$. Both plastic shreds were treated by a shear-type crusher. The PET shreds were bent and twisted by the crush so that they were blown up easily, but the PS shreds were not. After the crush of mixture of both plastics, air separation experiments were carried out using four types of air separators. The number and location of the baffle attached to them are different. With the separator with a baffle attached at the upper part, PET recoveries for the crushing time of 30, 60 and 90sec were 67, 98 and 99% respectably at the air flow rate of 3.5m/s, whereas PS recoveries were null regardless of the crushing time.

• Journal of the Korean Chemical Society
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• v.15 no.4
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• pp.205-209
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• 1971

The thermodynamic parameters for the solvolysis of the p-chlorobenzyl chloride taking place in the various aqueous mixtures were determined. From the application of these data to the formula ${\delta}_M{\Delta}H^{\neq}=a'Y+b{\delta}_M{\Delta}S^{\neq}$ the following conclusion was obtained: That the substrate constant a' differs in different aqueous solvent was found, and using each a' value the solvolysis mechanism of p-chlorobenzyl chloride in each aqueous mixture can be determined.

• Particle and aerosol research
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• v.12 no.4
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• pp.135-143
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• 2016

Removal of water contents in a gas is needed in industrial field of gas processing related on energy production/conversion, and environmental treatment. Inertial separators are economic devices for separating droplets from the gas stream. For accurate understanding of removal process in a curved vane mist eliminator, a numerical model including turbulent dispersion, evaporation and condensation of water vapor at surface of droplets is required. A two-stage curved vane mist eliminator has been modeled, and fluid flow of mixture of air and water vapor and droplet trajectories were solved simultaneously with taking into account two-way coupling. Removal efficiency of droplets with various inlet condition of relative humidities (RH, 40%, 90%, and 100%) were compared. As RH increased, the effect of evaporation decreased and inertial separation efficiencies of droplets obtained increased especially for droplets of diameter below 10 micrometers.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.1-6
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• 1992

The aspartame, $\alpha$-L-aspartyl-L-phenylalanine methylester, is an artificial sweetener. Taking advantage of the fact that the aspartame is a derivative of dipeptide, synthesis of aspartame from the artificial polypeptide made by an artificial gene has been attempted. The artificial polypeptide (LAP32), a polymer of tripeptide (aspartyl-phenylalanyl-lysine), was purified from the E. coli cells harboring a recombinant plasmid containing the artificial gene. This polypeptide was then digested with trypsin and carboxypeptidase B to produce dipeptide (Asp-Phe). Using the esterase activity of $\alpha$-chymotrypsin, the dipeptide was directly converted into Asp-Phe methylester in a water-methanol system. When the methanol concentration in reaction mixture was 25%, 50% of dipeptide was converted to the dipeptide methylester without producing any by-products.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.1024-1029
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• 2011

PVA/silica hybrid xerogels were synthesized by sonohydrolysis of a mixture of 2-way catalyzed TEOS and water solution of PVA. PVA was successfully removed from the xerogels through calcination and its removal was confirmed through TGA analysis of the calcined gel. Microstructure of the gels was studied through SEM, XRD and FTIR. Nitrogen sorption studies were conducted to find out surface area of different samples. It was found out that the samples having PVA removed through calcinations have higher surface area (411.64 $m^2$/g) than the samples (353.544 $m^2$/g) synthesized without any PVA. Adsorption properties of these xerogels synthesized by using different ratios of components were studied by taking Rhodamine G6 as a model adsorbate. The experiments were conducted at room temperature ($25^{\circ}C$). UV visible spectroscopy was used to measure the concentration of the dye before and after adsorption. The adsorption data of Rhodamine G6 on PVA modified silica is described by the Freundlich's adsorption model.

• Journal of Industrial Technology
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• v.11
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• pp.3-16
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• 1991

The lattice-fluid theory are adopted for modeling the phese equilibria in supercritical fluids, In order to investigate effects of the nonrandom distribution of holes in mixtures on the phase equilibria, the equation of state and the chemical potential of the binary miture are formulated with taking into account nonrandomness of holes distributions in the fluid mixture. The relations of phase equilibria formulated in this work are tested through predictions of solubility of heavy solids in supercritical fluids and predictions of high pressure phase equilibria of binary mixtures. Results obtained exhibit that the lattice fluid model with assumptions of nonrandomness of hole distributions is successful in quantatively mideling the phase equilibria of mixtures of molecules of dissimilar sizes, specifically solids-supercritical fluid mixtures.

• Structural Engineering and Mechanics
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• v.51 no.5
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• pp.823-845
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• 2014

Success in the excavation of foundations is commonly known as being very important in asserting stability. Furthermore, when the subjected formation is rocky and the use of explores is required, the demands of successful blasting are multiplied. The quick and correct estimation of excavation's characteristics may help the design of building structures, increasing their safety. The present paper proposes a new classification system which connects blastability and rock mass quality. This new system primarily concerns poor and friable rock mass, heavily broken with mixture of angular and rounded rock pieces. However, it should concern medium and good quality rock mass. The Blastability Quality System (BQS) can be an easy and widely - used tool as it is a quick calculator for blastability index (BI) and rock mass quality. Taking into account the research calculations and the parameters of BQS, what has been at question in this paper is the effect of BI magnitude on a geological structure.