• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.88-94
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• 1998

This study was investigated the application of biofiltration using cometabolic process to remediate gaseous toluene that are highly recalcitrant to adsorption, absorption and biodegradation. The investigation was conducted using specially built steel columns packed with granular activated carbon for removal of toluene and G.A.C was also coated with Pseudomonas putida microorganisms by addition of KH$_{2}$PO$_{4}$. The biofilter unit was operated in the condition of dry and 27.5% moisture content at gas loading rate of 12.5 l/min. Gaseous toluene taken from tedlar bag was analyzed by the use of G.C. equipped with F.I.D. detector. The removal efficiency of gaseous toluene was 85% at average inlet concentration of 970 ppm during dry operating condition. For gaseous toluene, 91% removal efficient was obtained at the filter material with moisture content and 97% removal efficiency was obtained with Pseudomonas putida microorganisms at gas loading rate of 12.5 l/min.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.403-404
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• 2009

This study has investigated application of the industrial by-product of reject ash and recycled fine aggregate to consider the economical issue to high flowing CLSM(controled low-strength material). But this high flowing CLSM is required more binder, so it has been estimated the influence of reject ash content, use of recycled fine aggregate and crushed sand, and air content about properties of CLSM.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.55-62
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• 2000

In this paper, a laboratory investigation was carried out to estimate the strength improvement of quicklime mixture with fly ash and rice husk ash for the effective use of surplus soils, and the shear strength with curing time was estimated at lime 10 percent with the change of fly ash and rice husk ash content. The effect of strength improvement has been established through the change of fly ash and rice husk ash content from the samples taken at Samsan region, Ulsan. The test results indicated that the presence of lime with fly ash and rice husk ash encouraged the stabilization efficiency of lime with fly ash and rice husk ash, and increased shear strength. Furthermore, it is necessary for inquiring into the relationship between the characteristics of strength and the chemical components.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.204-209
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• 1993

This investigation was undertaken for the purpose of studying the chemical properties of different kinds of spinach by various blanching procedure. Ascorbic acid, mineral and oxalic acid retention of spinaches, as well as blanch effluent composition were the major factors considered with Dong-cho(winter spinach) and vinylhouse grown spinach. Ash, crude protein, crude fat and vitamin C contents of Dong-cho were higher than those of vinylhouse spinach. On the other hand, vinylhouse grown spinach showed higher content in moisture, phosporous, calcium and oxalic acid. Most of the components in spinaches were decreased by increasing the blanching water volume and time. Reducing sugar and solid content in blanch effluent of Dong-cho were increased by increasing the blanching water volume and time, however, vinylhouse spinach showed no reducing sugar.

• Molecular & Cellular Toxicology
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• v.5 no.3
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• pp.243-249
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• 2009

Melamine, which is used to produce melamine resin for various industrial applications, has a high nitrogen content by mass. For this reason, it has been illegally added to foods to increase their apparent protein content. In the present investigation, melamine-induced oxidative damage of human lymphocyte DNA was evaluated by Comet assay. The in vitro oxidative DNA damage caused by melamine increased in a dose-dependent manner. This DNA damage was significantly inhibited by treatment with ascorbate. Moreover, the traditional Korean medicinal herb, named Acanthopanax, red ginseng and green tea markedly reduced the DNA damage. Various edible plant extracts also inhibited melamine-induced oxidative DNA damage in vitro. Melamine enhanced intracellular ROS generation, and this effect was suppressed by treatment with various antioxidants.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.113-118
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• 2003

An investigation has been carried out on collision-induced dissociation (CID) in the development of an analytical protocol for the determination of polycyclic aromatic hydrocarbons (PARs) by ion trap tandem mass spectrometry. Two different considerations were used to choose the optimal CID conditions for complex matrix environmental samples, namely, to determine the highest signal-to-noise (SIN) ratio and the other to eliminate the background interferences originated from complex matrix samples. The PAR content of agricultural soil was measured to estimate overall distribution of PAR in throughout the country, we collected and analyzed 226 soil samples from paddy and upland soil. The average content of total PAR in all samples was 236 ${\mu}g$ $kg^{-1}$, and the range was from 23.3 to 2, 834 ${\mu}g$ $kg^{-1}$. The overall distribution of PAR was found to be closely related to the pollution sources, the size of city and the type of industry.

• Journal of Pharmaceutical Investigation
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• v.15 no.3
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• pp.121-129
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• 1985

Influences of various waxes on the consistency of cream was investigated by inspections through microscope, rheometer and sensory test. Fatty acids, higher fatty alcohols, hydrocarbons, and some of natural waxes were used in this experiment. Most above waxes showed good state of emulsion at low concentration, but at higher concentration $(7.0{\sim}8.0%)$, they showed not only an unstable emulsion state but also a critical point of content in consistency. At this critical point of content, the consistency of w/o type cream was increased irregularly. So, it could be identified that consistency of a w/o type cream was strongly dependent on kinds and contents of waxes in continuous phase.

• Journal of Pharmaceutical Investigation
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• v.18 no.1
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• pp.9-13
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• 1988

Physicochemical properties of oil in water microemulsions containing soybean oil and egg phosphatide were observed for 3 weeks under the storage condition of $4^{\circ}C$ refrigerator. Changes in major fatty acid content, particle size distribution, rheogram, acid value and pH value were measured by gas chromatograph, laser particle sizer, Coulter counter and rheometer. From above experiments following conclusions were obtained; 1) Mean particle diameter was shifted from 240 to 266mm. 2) No significant changes were observed in the content of major fatty acids of soybean oil, rheogram, acid value and pH value.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.15-15
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• 2002

Homogeneous and crack-free potassium lithium niobate (K₃Li/sub 2-x/Nb/sub 5+x/O/sub 15/, 0＜x＜0.5, KLN) single crystals were successfully grown by the Czochralski technique. The KLN single crystals of several different compositions were employed for the investigation of the lattice vibration spectra using infrared Raman spectroscopy. The characteristic Raman spectra of the [NbO/sub 6/]/sup 7-/ octahedral ions were strikingly influenced by the Li ion content. The symmetric stretch vibrational modes V₁, V₂ are broadened, and the symmetric bend vibration mode V/sub 5/ is broadened and even split into three peaks with increasing the Li content, supporting that the bend vibration modes of the [NbO/sub 6/]/sup 7-/ octahedrons are obviously perturbed by Li ions in the C site. Enhanced Raman peak intensities after the post annealing at 900℃ and for 24 h evidenced that a residual stress in as-grown crystals was negligible and only a defect concentration might be reduced.

• Journal of Korean Society on Water Environment
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• v.31 no.2
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• pp.134-141
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• 2015

The focus of this study was to observe the growth of Chlorella vulgaris and Botryococcus braunii under mixotrophic conditions (i.e., added acorn) with the aim of increasing biomass and triacylglycerols (TAGs) content. The result of investigation indicated that the acorn contains a lot of carbonate (87.29%) and glucose (97.99 mg%). A significant growth of biomass was obtained when grown in acorn rich environment comparing to autotrophic conditions. 3 g/L acorn yielded the highest biomass concentration for these strains. Thus, the biomass productivity with 3 g/L acorn was obtained 2.31 times and 2.10 times higher than that of authotrophic conditions for Chlorella vulgaris and Botryococcus braunii, respectively. The maximum amount of TAGs was reached 14.35% and 18.41% for Chlorella vulgaris and Botryococcus braunii, respectively, in the growth medium with 5 g/L acorn. The effect of acorn could enhance the investigated microalgae growth, biomass productivity and TAGs content. This provides a feasible way to reduce the cost of bioenergy production from microalgae.