• Natural Product Sciences
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• v.9 no.4
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• pp.256-259
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• 2003

The pet ether extract of Caesalpinia pulcherrima, leaves was studied for its antinociceptive, anti-inflammatory and antipyretic property. The extract at doses of 50 and 200 mg/kg, p.o., significantly (p<0.05) reduced the number of writhing induced by acetic acid and inhibited the late phase (20-30 min) in formalin test in mice. The extract failed to increase the pain threshold level in tail immersion test in mice. In carrageenan induced paw edema in rats and in acetic acid induced increase in vascular permeability test in mice, the extract (50-600 mg/kg, p.o.) failed to produce any significant activity. While in cotton pellet granuloma test, the extract at doses of 200 and 600 mg/kg (p.o.) significantly (p<0.05) reduced the granuloma formation and was comparable to reference drug, dexamethasone. In ethylpheylpropiolate ear edema test 0.5 mg and 1 mg/ear application of extract significantly (p<0.05) inhibited ear edema. In yeast induced hyperthermia in rats, the extract did not produce any reduction in temperature. The results suggest that the extract acts peripherally to produce analgesic action and anti-inflammatory activity through steroidal mechanism.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.514-519
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• 2001

Converter has been slag produced 10 million tons per year in Japan. It is a steel making by product produced in the same way as the blast-furnace slag. Though blast-furnace slag is being used effectively as a concrete admixture, the converter stag has never been used effectively because of the expansion action of contained free lime and iron oxide. This is an important environmental problem in the steel industry. Beta-2CaOSiO$_2$(beta-C$_2$S) is contained 40 percent in converter slag, therefore it is very promising as a concrete admixture. We proposed an accelerated aging processes capable of stabilizing the converter slag in a short time. The converter slag is dipped into alkali aqueous solution after heating at low temperature. It was subsequently ground to a grain size of 75 ${\mu}{\textrm}{m}$ , inner 30 percent of OPC. The properties of mortar and concrete using the blended cement were determined. As a result, it has become apparent that the expansion was reduced and long term compressive strength was increased while that at early ages was not so remarkable. The hydration exotherm rate was lower than that of the OPC.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.1
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• pp.1-6
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• 2010

Methylene blue is a very effective reducer of drug-induced methemoglobinemia. It has dose-dependent oxidation or reduction properties. In most cases, a dose of 1 to 2 mg/kg IV given over 5 minutes and immediately followed by a 15- to 30-mL fluid flush to minimize the local pain is both effective and relatively safe. The onset of action is quite rapid, and the effects are usually seen within 30 minutes. The dose may be repeated after 30 to 60 minutes and then every 2 to 4 hours as needed. The total dose should not exceed 7 mg/kg as a single dose or 15 mg/kg within 24 hours. Repeated treatment may be needed for treating compounds that have prolonged elimination or those compounds that undergo enterohepatic recirculation (e.g., dapsone). Methylene blue can cause dose-related toxicity. At high doses, methylene blue can also induce an acute hemolytic anemia and rebound methemoglobinemia. The reasons for treatment failure with methylene blue include ineffective GI decontamination, the existence of other forms of hemoglobin (e.g., sulfhemoglobin), a low or high dose of methylene blue and the toxicokinetics of some agents, such as aniline, benzocaine or dapsone.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.75-80
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• 2002

Enormous volumes of mining wastes from the abandoned and closed mines are disposed without a proper treatment at Southeastern part of Kangwon Province. Erosion of these wastes contaminates soil, surface water, and sediments with heavy metals. Objectives of this research were to fractionate heavy metals in the mine waste and to assess the potential S. P. A. G.(Soil Pollution Assesment Guidance) of each metal fraction. Mine wastes analyzed for physical and chemical properties. pH of wastes ranged from 3.3 to 8.0. Contents of total N and loss on ignition matter were in the ranges of 0.2~5.6%, and 0.8~15.3%, respectively. Heavy metals in the wastes were higher in the coal mines than those in the other mine wastes. Total concentrations of metals in the wastes were in the orders of Pb > Zn > Cu > Cd, exceeded the corrective action level of the Soil Environment Conservation Law and higher than the natural abundance levels reported from uncontaminated soils. Relative distribution of heavy metal fractions was residual > organic > reducible > carbonate > adsorbed, reversing the degree of metal bioavailability. Mobile fractions of metals were relatively small compared to the total concentrations. Soil Pollution Assesment Guidance(SPAG) values were ranged from 0.08 to 9.14 based on labile fraction of metal concentrations. SPAG values of labile concentration were lower than those of total concentration.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.4
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• pp.152-156
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• 2005

The cultivation of akoya pearls was carried out with bio bead nucleus prepared using the hydroxyapatite. The akoya pearls cultured with bio bead nucleus were shown the color of cream. The luster and orient effect created by an action of the light from nacre were magnificent. The result of XRD is found that the nacre is a calcium carbonate of aragonite form. From the result of SEM, it is found that layers of calcium carbonate and conchiolin are stratified. The properties of akoya pearls cultured with bio bead nucleus are same those of akoya pearl cultivated with bead nucleus made from washboard shell. Because of the bio bead nucleus developed in this study has such a high capacity in producing various sizes and shapes, it is very advantageous for the cultivation of akoya pearls.

• International Journal of Ocean System Engineering
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• v.1 no.4
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• pp.230-235
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• 2011

Reinforced polyurethane foam (RPUF) is one of the important materials of Mark III type insulation systems used in liquefied natural gas (LNG) cargo containment systems. However, RPUF is the most difficult material to use with regard to its safety assessment, because there is little public and reliable data on its mechanical properties, and even some public data show relatively large differences. In this study, to investigate the structural response of the system under compressive loads such as sloshing action, time-dependent characteristics of RPUF were examined. A series of compressive load tests of the insulation system including RPUF under various temperature conditions was carried out using specimens with rectangular section. As a result, the relationship between deformation of RPUF and time is linear and dependent on the loading rate, so the concept of strain rate could be applied to the analysis of the insulation system. Also, we found that the spring constant tends to converge to a value as the loading rate increases and that the convergence level is dependent on temperature.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.207-215
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• 2004

In this study, the upper bound theory is applied to a reinforced slope to develop an limit state analysis method. As processing of this upper bound theory in formulating finite element, the basic idea of numerical method can be obtained from a macroscopic point of view with an anisotropic homogeneous material. The reinforced soil strength reliability depends on properties of reinforcements which consist of the interaction of interfaces between back fill and reinforcements. Both soil's mechanical property and overall behaviour of reinforced soil can be controlled via arranging geometry and relative proportions of reinforced soil. Therefore, the upper bound theory can not only predict the particular limit state action of reinforced soil slope but also is efficiently able to estimate the local plastic failure.

• Steel and Composite Structures
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• v.22 no.1
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• pp.45-61
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• 2016

The domestic and foreign scholars conducted many studies on mechanical properties of wave web steel beam and high-strength spiral stirrups confined concrete columns. Based on the previous research work, studies were conducted on the anti-seismic property of the end plate bolt connected wave web steel beam and high-strength spiral stirrups confined concrete column nodes applied with pre-tightening force. Four full-size node test models in two groups were designed for low-cycle repeated loading quasi-static test. Through observation of the stress, distortion, failure process and failure mode of node models, analysis was made on its load-carrying capacity, deformation performance and energy dissipation capacity, and the reliability of the new node was verified. The results showed that: under action of the beam-end stiffener, the plastic hinges on the end of wave web steel beam are displaced outward and played its role of energy dissipation capacity. The study results provided reliable theoretical basis for the engineering application of the new types of nodes.

• Advances in concrete construction
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• v.9 no.5
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• pp.459-467
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• 2020

Mechanical and thermal properties of composite sandwich wall panels are affected by changes in their external environment. Humidity and temperature changes induce stress on wall panels and their core connectors. Under the action of ambient temperature, temperature on the outer layer of the wall panel changes greatly, while that on the inner layer only changes slightly. As a result, stress concentration exists at the intersection of the connector and the wall blade. In this paper, temperature field and stress field distribution of UHPC-RW-RC (Ultra-High Performance Concrete - Rock Wool - Reinforced Concrete) wall panel under high temperature-sprinkling and heating-freezing conditions were investigated by using the general finite element software ABAQUS. Additionally, design of the connection between the wall panel and the main structure is proposed. Findings may serve as a scientific reference for design of high performance composite sandwich wall panels.

• Steel and Composite Structures
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• v.23 no.1
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• pp.1-16
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• 2017

This paper is presented to solve the buckling problem of functionally graded truncated conical shells subjected to displacement-dependent pressure which remains normal to the shell middle surface throughout the deformation process by the semi-analytical finite strip method. Material properties are assumed to be temperature dependent, and varied continuously in the thickness direction according to a simple power law distribution in terms of the volume fraction of a ceramic and metal. The governing equations are derived based on first-order shear deformation theory which accounts for through thickness shear flexibility with Sanders-type of kinematic nonlinearity. The element linear and geometric stiffness matrices are obtained using virtual work expression for functionally graded materials. The load stiffness also called pressure stiffness matrix which accounts for variation of load direction is derived for each strip and after assembling, global load stiffness matrix of the shell which may be un-symmetric is formed. The un-symmetric parts which are due to load non-uniformity and unconstrained boundaries have been separated. A detailed parametric study is carried out to quantify the effects of power-law index of functional graded material and shell geometry variations on the difference between follower and non-follower lateral buckling pressures. The results indicate that considering pressure stiffness which arises from follower action of pressure causes considerable reduction in estimating buckling pressure.