• International Journal of Highway Engineering
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• v.9 no.4
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• pp.93-104
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• 2007

This study evaluates the mechanical properties of steel fiber reinforced porous concrete for pavement according to content of slag aggregate and fly ash to elicit the presentation of data and the way to enhance its function for the practical field application of porous concrete as a material of pavement. As a result, void ratio and permeability coefficient of porous concrete for pavement increased a little as mixing rate of slag aggregates increased. Void ratio and permeability coefficient increased a lot as mixing rate of fly ash decreased. As fly ash was mixed, national regulation of permeable concrete for pavement(8% and 0.1 cm/sec) was met. Compressive strength and flexural strength decreased as mixing rate of slag aggregates increased, but they increased a lot as mixing rate of fly ash increased. Even when slag aggregates were mixed 50% with 5% fly ash mixed, national regulation of pavement concrete(18MPa and 4.5MPa) was met. In addition, compared to non-mixture, flexural strength increased about 22.8% when 0.75vol.% of steel fiber was added. Regarding sliding resistance, BPN increased as mixing rate of slag aggregates increased. But BPN decreased as fly ash was mixed. Compared to crushed stone aggregates, abrasion resistance and fleers-thaw resistance decreased as mixing rate of slag aggregates increased. When fly ash was mixed, abrasion resistance and freeze-thaw resistance improved remarkably. Compared to non-mixture, 10% mixture of fly ash improved abrasion resistance and freeze-thaw resistance about 5.6% and 14.3 respectively.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.171-185
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• 2017

${\gamma}$-aminobutyric acid (GABA) is a non-proteinogenic amino acid biosynthesized through decarboxylation of L-glutamic acid by glutamic acid decarboxylase. GABA is believed to play a role in defense against stress in plants. In humans, it is known as one of the major inhibitory neurotransmitters in the central nervous system, exerting anti-hypertensive and anti-diabetic effects. In this report, we wanted to enhance the GABA production from the barley leaf and corn silk by culturing them with lactic acid bacteria (LAB). The barley leaf and corn silk were mixed with various weight combinations and were fermented with Lactobacillus plantarum in an incubator at $30^{\circ}C$ for 48 h. After extracting the fermented mixture with hot water, we evaluated the GABA production by thin layer chromatography and GABase assay. We found that the fermented mixture of the barley leaf and corn silk in a nine to one ratio contained a higher level of GABA than other ratios, meaning that the intermixture and fermentation technique was effective in increasing the GABA content. We also tested several biological activities of the fermented extracts and found that the extracts of the fermented mixture showed improved antioxidant activities than the non-fermented extracts and no indication of cytotoxicity. These results suggest that our approach on combining the barley leaf and corn silk and its fermentation with LAB could lead to the possibility of the development of functional foods with high levels of GABA content and improved biological activities.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.196-205
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• 2001

The results of examining cultivation of tlyster mushroom using NSM(Non Sterilized Media) for determining the condition of artificially culturing oyster mushroom(Pleurotus ostreatus) are as follows. Mycelial growth an[1 density of oyster mushroom. were the highest in the medium of waste cotton(spinning) : corn cob(80 : 20, V/V) followed by the order of rice bran, beet pulp. Expecially, mycelial growth and density of oyster mushroom is the lowest at the mixture rate of 80% waste cotton(spinning) : 10% beet pulp. Mycelial growth and density of oyster mushroom. were the highest in the medium of cotton seed hull and beet pulp mixture followed by the order of rice bran, corn cob. Expecially, mycelial growth and density of oyster mushroom is the lowest at the mixture rate of 80% cotton seed hull : above 20% rice bran. Mycelial growth and density of oyster mushroom were the highest in the medium rate of 70% waste cotton(spinning), 10% corn cob and 10% beet pulp(V/V). Mycelial growth and density of oyster mushroom were the highest in the medium rate of 70% cotton seed hull , 10% corn cob and 10% beet pulp(V/V). Optimal concentration of NSM for the mycelial growth and density of oyster mushroom were shown to be 500 times concentration. Optimal water contents for the mycelial growth and density of NSM was 70%.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.50-58
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• 2020

When the concrete surface layer is damaged, The method of impregnating the concrete surface with a water repellent cannot secure the expected durability. Recently, various waterproofing and water-repellent materials were mixed into concrete or mortar to secure water repellency even inside cracks, but compressive strength was greatly reduced. In order to overcome the decrease in compressive strength, there has not yet been a study using the merits of organic and inorganic materials at the same time, so in this study, the physical properties and water repellency performance were evaluated by mixing an organic/inorganic composite water repellent appropriately mixed with an organic and inorganic material into the mortar. When mixed with organic/inorganic water repellent, the flow and air content were reduced by about 10% and 50% compared to the Liquid specimen. In the case of the P6L1 specimen, it was confirmed that the compressive strength decreased by about 3.5% compared to the non-mixed mortar at 39.5 MPa, the same as the existing water repellent, Powder. Water-repellent performance The organic-inorganic composite water repellent mixture specimen confirmed higher water repellency than the existing water repellent mixture powder, and the chloride penetration resistance evaluation result showed that the organic-inorganic composite water repellent mixture specimen reduced the passing charge by about 45% compared to the non-mixed mortar. In summary, it is judged that the P5L1 organic/inorganic composite water repellent mixed with a powder water repellent and a liquid water repellent in a ratio of 5:1 is the most reasonable to prevent the decrease in compressive strength and secure water repellency.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.547-555
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• 2009

This study was performed to determine the minimum dose of Poloxamer/Sodium alginate (PX/SA) mixture on preventing intraperitoneal adhesions to evaluate organ toxicity. Twenty five healthy adult mongrel dogs (weighing 4.68${\pm}$1.67 kg) were divided into five experimental groups composed of five dogs respectively; negative control group (NC, non-treated), positive control group (PC, 2% carboxymethyl chitosan solution treated), and experiment 1 group (E1, 0.25 ml PX/SA mixture of abraded area), experiment 2 group (E2, 0.5 ml PX/SA mixture of abraded area), experiment 3 group (E3, 1.0 ml PX/SA mixture of abraded area). Venous blood specimens were collected from all experimental animals for hematologic and biochemical analysis: WBC, fibrinogen, AST, ALT, ALP, BUN and creatinine. The anti-adhesion effect was evaluated using a serosa abrasion model. The denuded ileum was coated with PX/SA mixture, carboxymethyl chitosan solution or neither. The tensile strength of the adhesion site was evaluated with a tensiometer. For histopathological examination, tissue samples of the liver and kidney were collected from all dogs. According to the results, the frequency and tensile strength values for adhesion separation in PX/SA group were significantly lower than those in negative control group (p < 0.05). In E2 group, the tensile strength was significantly decreased in consideration of PX/SA dose. The values of AST, ALT, ALP, BUN and creatinine of the control and the experimental groups showed no statistical differences. No obvious microscopic differences were noted among tissue sections obtained from all groups. The results suggest that PX/SA mixture may be effective on reducing peritoneal adhesion formation in dog and that 0.5 ml PX/SA mixture of abraded area is most effective dose. Moreover, PX/SA mixture was considered not to have toxicity for the liver and the kidney.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.145-152
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• 2014

To evaluate the improving effects of antioxidant activity, we observed antioxidant capacities such as electron donating ability (EDA), Ferric reducing antioxidant power (FRAP), inhibitory activity of xanthine oxidase (XO) and aldehyde oxidase (AO), and sensory characteristics on mixture of Smilax china L. root water extract added with water extract of fermented S. china L. leaf by Aspergillus oryzae (FSCL). Those contents of mixture with higher ratio of FSCL were proportionally high. And OD475 of mixture with higher ratio of FSCL was almost proportionally high ($R^2=0.9850$). Antioxidant capacities of EDA and FRAP of the mixture was higher than that of non-mixture. In addition, XO inhibitory activity ($IC_{50}$) of A (1.19) was 59.80% higher than that of F (2.96), and the activity of mixture by the higher ratio of FSCL was proportionally low ($R^2=0.9490$). Taste acceptability of A was slightly higher than that of F, whereas that of C was highest. And color acceptability of 40-80% mixture was higher than those of A, F, and B. Overall acceptability of C and D was highest than those of others. Moreover, hot water extract of S. china L. leaf fermented with A. oryzae was maroon color, which looks like Puerh tea style, and mixture of S. china L. root extract added with hot water extract of S. china L. leaf was high acceptability of beverage. These results suggest that mixture of extract of S. china L. root and hot water extract of S. china L. leaf fermented with A. oryzae could improve antioxidant activities.

• Journal of Aquaculture
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• v.11 no.1
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• pp.91-97
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• 1998

This paper introduces to a simple culture method and growth of axenic (bacteria-free) rotifer Brachionus rotundiformis for seed stock of rotifer mass culture. This rotifer axenic culture method is based on the washing and transferring with sterilized sea water and modified antibiotic mixture AM9 solution. Population growth (final density on day 16) of axenic cultured rotifer were maintained with a high density and stable growth compared with the control of non-axenic culture (general culture style) through the 3 times-rerunning experiments (trial 1, 2 and 3). But the egg carrying rates of amictic females were not different between the axenic-and non-axenic culture condition. Although, rotifer density was higher in axenic culture, the food (Nannochloropsis oculata) was still remained unutilized than that of the non-axenic culture in third trial culture. These results suggest the possible existence of harmful bacteria for the rotifer population growth in the trial 1 and 3 of non-axenic culture compared to the trial 2. This axenic rotifer culture method is valuable for seed stock of the stable rotifer mass cultures.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.3
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• pp.49-55
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• 2012

Even though corrugated boards are the most common packaging materials for agricultural products, conventional corrugated boards are not able to maintain the freshness of agricultural products. In order to overcome the limitations of conventional corrugated boards, a new hybrid corrugated board-composed of linerboard, a corrugating medium, and non-woven fabric-was designed to possess antibacterial, high porous and shock-absorbing properties. In this study, we compared the physical properties of non-woven fabric to those of the base papers of conventional corrugated boards and developed a new adhesive system as a first step toward manufacturing the hybrid corrugated board. We found that the non-woven fabric, which had relatively high elongation, was applicable in the corrugated board process, and that the manufacturing conditions must be controlled in order to prevent the break of the non-woven fabric. The mixture of starch and styrene-butadiene (SB) latex showed high adhesive strength, but the addition level of SB latex should not exceed 30% in starch solution.

• Journal of Ginseng Research
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• v.36 no.1
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• pp.47-54
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• 2012

Korean red ginseng (KRG) has been used worldwide as a traditional medicine for the treatment of various reproductive diseases. Gonadotropin releasing hormone (GnRH) neurons are the fundamental regulators of pulsatile release of gonadotropin required for fertility. In this study, an extract of KRG (KRGE) was applied to GnRH neurons to identify the receptors activated by KRGE. The brain slice patch clamp technique in whole cell and perforated patch was used to clarify the effect of KRGE on the membrane currents and membrane potentials of GnRH neurons. Application of KRGE (3 ${\mu}g$/${\mu}L$) under whole cell patch induced remarkable inward currents (56.17${\pm}$7.45 pA, n=25) and depolarization (12.91${\pm}$3.80 mV, n=4) in GnRH neurons under high $Cl^-$ pipette solution condition. These inward currents were not only reproducible, but also concentration dependent. In addition, inward currents and depolarization induced by KRGE persisted in the presence of the voltage gated $Na^+$ channel blocker tetrodotoxin (TTX), suggesting that the responses by KRGE were postsynaptic events. Application of KRGE under the gramicidin perforated patch induced depolarization in the presence of TTX suggesting its physiological significance on GnRH response. Further, the KRGE-induced inward currents were partially blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; non-NMDA glutamate receptor antagonist, 10 ${\mu}M$) or picrotoxin (PIC; $GABA_A$ receptor antagonist, 50 ${\mu}M$), and almost blocked by PIC and CNQX mixture. Taken together, these results suggest that KRGE contains ingredients with possible GABA and non-NMDA glutamate receptor mimetic activity, and may play an important role in the endocrine function of reproductive physiology, via activation of $GABA_A$ and non-NMDA glutamate receptors in GnRH neurons.

• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.27-35
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• 2024

Fuel gases such as methane and propane are used in explosion hazardous area of domestic plants and can form non-uniform mixtures with the influence of process conditions due to leakage. The fire-explosion risk assessment using literature data measured under uniform mixtures, damage prediction can be obtained the different results from actual explosion accidents by gas leaks. An explosion characteristics such as explosion pressure and flame velocity of non-uniform gas mixtures with concentration change similar to that of facility leak were examined. The experiments were conducted in a closed 0.82 m long stainless steel duct with observation recorded by color high speed camera and piezo pressure sensor. Also we proposed the quantification method of non-uniform mixtures from a regression analysis model on the change of concentration difference with time in explosion duct. For the non-uniform condition of this study, the area of flame surface enlarged with increasing the concentration non-uniform in the flame propagation of methane and was similar to the wrinkled flame structure existing in a turbulent flame. The time to peak pressure of methane decreased as the non-uniform increased and the explosion pressure increased with increasing the non-uniform. The ranges of K_G (Deflagration index) of methane with the concentration non-uniform were 1.30 to 1.58 [MPa·m/s] and the increase rate of K_G was 17.7% in methane with changing from uniform to non-uniform.