• Archives of Pharmacal Research
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• v.24 no.3
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• pp.249-255
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• 2001

We studied the effect of aqueous extract of Magnolia officinalis bark (Magnoliaceae) (MOAE) on the immediate hypersensitivity reaction. MOAE (0.01 to 1g/kg) dose-dependently inhibited compound 48/80 induced systemic anaphylaxis in rats. MOAE (0.1 and 1g/kg) also significantly inhibited local immunoglobulin E (lgE)-mediated passive cutaneous anaphylactic reaction. When MOAE was pretreated at concentrations ranging from 0.01 to 1g/kg, the levels of plasma histamine were reduced in a dose-dependent manner. MOAE (0.001 to 1 mg/ml) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-dinitrophenyl (DNP) Igl. The level of cyclic AMP (CAMP) in RPMC, when MOAE was added, significantly increased compared with that of the normal control. Moreover, MOAE (0.01 to 1 mg/ml) had a significant inhibitory effect on anti-DNP Igl-induced tumor necrosis factor-$\alpha$ production from RPMC. These results indicate that MOAE inhibits immediate hypersensitivity reaction in vivo and in vitro.

• Journal of computational fluids engineering
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• v.16 no.2
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• pp.94-101
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• 2011

The fast pyrolysis characteristics of lignocellulosic biomass are investigated for a bubbling fluidized bed reactor by means of computational fluid dynamics (CFD). To simulate multiphase reacting flows for gases and solids, an Eulerian-Eulerian approach is applied. Attention is paid for the primary and secondary reactions affected by gas-solid flow field. From the result, it is scrutinized that fast pyrolysis reaction is promoted by chaotic bubbling motion of the multiphase flow enhancing the mixing of solid particles. In particular, vortical flow motions around gas bubbles play an important role for solid mixing and consequent fast pyrolysis reaction. Discussion is made for the time-averaged pyrolysis reaction rates together with time-averaged flow quantities which show peculiar characteristics according to local transverse location in a bubbling fluidized bed reactor.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.10a
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• pp.25-30
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• 1992

Since the first report on the damage of concrete structures due to alkali-aggregate reaction by T.E Stanton in 1940, cases of the damage are being reported in many countries. in the country, it is necessary to research the alkali-aggregate reaction of the crushed stone because of the short comings of natural aggregate and increasing needs of crushed stones. In this research, crushed stones from 63 local sites are collected and tested by ASTM C 289 chemical method.. The results show that most of the crushed stones are innocuous. However, the crushed stones from three sites are deleterious to the reaction by JIS A 5308. Petrographic and Mortar-Bar test will be carried out to find out any possibility of deleteriousness of the crushed stones

• Journal of Mechanical Science and Technology
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• v.18 no.8
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• pp.1470-1478
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• 2004

In this paper, a new 'presumed' Probability Density Function (PDF) approach coupled with a Lagrangian tracking method is proposed for turbulent combustion modeling. The test and the investigation of the model are conducted by comparing the model results with DNS data for a premixed flame subjected in a decaying turbulent field. The newly constructed PDF, which incorporates the instantaneous chemical reaction term, demonstrates consistent improvement over conventional assumed PDF models. It has been found that the time evolution of the mean scalar, the variance and the mean reaction rate are strongly influenced by a parameter deduced by a Lagrangian equation which takes into account explicitly the local reaction rate. Tests have been performed for a moderate Damkohler number, and it is expected the model may cover a broader range of Damkohler number. The comparison with the DNS data demonstrates that the proposed model may be promising and affordable for implementation in a moment-equation solver.

• Natural Product Sciences
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• v.10 no.1
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• pp.24-28
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• 2004

The effects of aqueous extract of Artemisia iwayomogi (Compositae) (AIAE) on the mast cell-dependent allergic and inflammatory reactions were investigated. AIAE (0.05 to 1 g/kg) dose-dependently inhibited systemic allergic reaction induced by compound 48/80 in mice. AIAE (0.1 and 1 g/kg) also significantly inhibited local allergic reaction activated by anti-DNP IgE. AIAE (0.001 to 1 mg/ml) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80. Moreover, AIAE inhibited the secretion of interleukin (IL)-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated human mast cell line (HMC-1) cells. These results provide evidence that AIAE may be beneficial in the treatment of allergic diseases.

• Advances in Traditional Medicine
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• v.1 no.1
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• pp.82-88
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• 2000

We investigated the effect of aqueous extract of Cichorium intybus (CIAE) on mast cell-mediated immediate type allergic reactions. CIAE dose-dependently inhibited systemic anaphylactic reaction induced by compound 48/80 in mice. Especially, CIAE inhibited compound 48/80-induced anaphylactic reaction 100% with the dose of 1000 mg/kg. CIAE 1000 mg/kg also significantly inhibited local anaphylactic reaction activated by anti-dinitrophenyl (DNP) IgE. When mice were pretreated with CIAE at a concentration ranging from 0.1 to 1000 mg/kg, the plasma histamine levels were reduced in a dose-dependent manner. CIAE (1 to 1000 g/ml) dose-dependently inhibited histamine release from the rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. These results indicate that CIAE inhibits mast cell-mediated immediate-type allergic reactions.

• Journal of environmental and Sanitary engineering
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• v.11 no.3
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• pp.29-35
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• 1996

Numerical solutions were obtained to the model equations for various parameters characterizing the pore structure, effective internal diffusion and the chemical reaction constant. The conversion was decreased with the cause of pore closure at the surface of reacting particles, reduction of porosity, surface area of reaction and effective diffusion coefficient in the solid with the progress of reaction. Total conversion was strongly depend on the local conversion at surface. According to the decreasing of impregnated concentration of the copper oxide and the increase of the flue gases concentration, total conversion was increased. And the conversion were affected by gas flow rate and pore size distribution of the reacting solid.

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1636-1644
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• 2017

The main purpose of this article is to describe the magnetohydrodynamic stagnation point flow of Walter-B nanofluid over a stretching sheet. The phenomena of heat and mass transfer are based on the involvement of thermal radiation and chemical reaction. Characteristics of Newtonian heating are given special attention. The Brownian motion and thermophoresis models are introduced in the temperature and concentration expressions. Appropriate variables are implemented for the transformation of partial differential frameworks into sets of ordinary differential equations. Plots for velocity, temperature, and nanoparticle concentration are displayed and analyzed for governing parameters. The skin friction coefficient and local Nusselt and Sherwood numbers are studied using numerical values. The temperature and heat transfer rate are enhanced within the frame of the thermal conjugate parameter.

• International Journal of Concrete Structures and Materials
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• v.1 no.1
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• pp.75-81
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• 2007

The concrete pavement of the Seohae Highway in Korea has suffered from serious distress, only four to seven years after construction. Deterioration due to Alkali-Silica Reaction (ASR) has seldom been reported per se in Korea, because the aggregate used for the cement concrete has been considered safe against alkali-silica reaction so far. The purpose of this study is to examine the deterioration caused by an alkali-silica reaction of concrete pavement in Korea. The investigation methods included visual inspection and Automatic Road Analyzer (ARAN) analysis of surface cracks, coring for internal cracks, stereo microscopic analysis, scanning electronic microscope (SEM) analysis, and electron dispersive X-ray spectrometer (EDX) analysis. The results are presented as follows: the crack pattern of the concrete pavement in Korea was longitudinal cracking, map cracking or D-cracking. Local areas of damage were noticed four to five years after construction. The cracks started from edges or joints and spread out to slabs. The most intensive cracking was observed at the intersection of the transverse and longitudinal joints. Where cracking was the most intense, pieces of concrete and aggregate had spalled away from top surface and joint interface area. The progress of deterioration was very fast. The reaction product of alkali-silica gel was clearly identified by its generally colorless, white, or very pale yellow hue seen through a stereo optical microscopy. The typical locations of the reaction product were at the interface between aggregate and cement paste in a shape of a rim, within aggregate particles in the cracks, and in the large void in the cement paste. Most of the white products were found at interface or internal aggregates. SEM and EDX analysis confirmed that the white gel was a typical reaction product of ASR. The ASR gel in Korea mainly consisted of Silicate (Si) and Potassium (K) from the cement. The crack in the concrete pavement was caused by ASR. It seems that Korea is no longer safe from alkali-silica reaction.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.876-878
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• 1999

Internal tin processed Nb3Sn wires with different diameter were locally heated before reaction heat treatment. Local heating at the intermediate state of drawing process decreased the superconducting properties and workability. When the local heating temperatures were higher than melting point of Sn, non-Cu Jc's decreased significantly.