• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1185-1191
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• 2005

Published correlation equations of the enthalpy of vaporization are reviewed and a new four-parameter correlation equation is proposed. Performance of the proposed equation is examined using the ASHRAE data for 22 pure substance refrigerants as reference data. The new equation yields an average absolute deviation of $0.05\%$, which is smaller than those of published equations, such as equations of Guermouche-Vergnaund $(0.08\%)$, Aerebrot $(0.13\%)$, Radoz-Lydersen $(0.08\%)$, and Somayajulu $(0.08\%)$. The three adjustable parameters of the modified correlation are optimized and reported for 22 substances. The equation proposed in this work is valid over the entire temperature range where data points exist.

• YAKHAK HOEJI
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• v.38 no.4
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• pp.394-400
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• 1994

As a previous step for the development of immunostimulating substance from marine natural products the two new lectins, MLA-II and MLA-III, have been isolated and purified from the hemolymph of Meretrix lusoria in addition to the previously reported MLA-I. The new lectins molecules were characterized as pure by electrophoretic studies.

• Journal of Plant Biology
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• v.14 no.1
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• pp.1-4
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• 1971

To determine the amylase fromation mechanism and the effect of GA. in germinating barley seeds, they were divided into embryo-less seed, isolated embryo, aleurone layer and pure endosperm etc., treated with GA, and cultured separately or in mixed lots. The result obtained are as follows. 1) The amylase of barley seed is formed in the aleurone layer under the effect of inducing materials excreted from the embryo. 2) The embryonic materials amylase formation could be substituted for by GA. Therefore it can be presumed that the substance produced by the embryo which induces amylase synthesis is probably GA or material similar to it.

• Korean Journal of Veterinary Service
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• v.35 no.1
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• pp.25-31
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• 2012

This study examined the efficacy of natural ingredient formulated herbal medicine as feed additives against coccidiosis in broiler chicken. Medicinal herbs used in this study were Artemisia annua, Pulsatilla chinensis, Clematis chinensis and Scutellaria baicalensis. Two week old chicks were administered with 1% ingredient formulated herbal medicine. Observations of the efficacy were confirmed by examining the lesion score, histopathological appearance of cecum, shedding of fecal oocyst and production index in farm. S. baicalensis of the most effective substance were analyzed by UPLC. The results are as follows; among various types of Chinese medicine, the most efficacious ingredient was found to be pure bicalein. The major index substance is bicalein and $13{\mu}g/ml$ per gram was found. Feeding of chickens with S. baicalensis induced the coccidiostat effect and reduced the fecal shedding of E. tenella oocyst by 14%. Experimental results on a farm, feed conversion ratio and weight gain and production rate in the group with natural ingredient formulated additives than in control group increased. The rate of weight gain (%) in each experimental group showed 108% and 126% increase while the mortality rate was 1.4% lower than the control group. The investigation showed that the most efficacious ingredient was found to be S. baicalensis among herbal medicine products for coccidiostats. However, as it was found in the farm experiment that pure S. baicalensis alone is economically unviable. The additives with cocktailed of efficacious ingredient are suggested to be implemented for effective protection against coccidiosis.

• Applied Biological Chemistry
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• v.4
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• pp.23-28
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• 1963

Various species of the genus Capsicum contain in their fruits an intensively sharp and pungent substance, Capsaicin, which was first isolated in an almost pure state by Thresh. Containing the pungent principle, Capsicums are used extensively in food as a spice and in medicine as a rubefacient and carminative. Numerous methods have been proposed for the isolation, the chemical structure and the quantitative determination of Capsaicin. Modifying the several methods described before, the Capsaicin contents in various species of the genus Capsicum were determined as follows. (1) The isolation of pure Capsaicin was the essential first step for the determination of Capsaicin contents. Powdered cayenne pepper was extracted with acetone. By the method of ether alkali partition extraction slightly modified at this laboratory and by the recrystallization with light petroleum ether that was repeated ten times, the pure crystalline Capsaicin was obtained. Using this Capsaicin, the standard absorption curve was drawn with Beckman spectrophotometer model DU for the quantitative determination of Capsaicin. 92) The powdered sample was extracted in a Soxhlet extractor with ether-acetone solvent system(3:1) for 25 hours. Capsaicin in this ether-acetone extracts was efficiently separated in a pure state by paper partition chromatography using 58% methanol solution as developing agent. It was found that 58% methanol was one of the most valuable solvent to separate Capsaicin from impurities such as sterols, fatty acids, waxes and carotenoid pigments. (3) The colorimetric method modifying the Schulte-Kruger's method which consists of measuring the red color produced with diazobenzenesulphonic acid was used. Capsaicin in various species of the genus Capsicum was determined quantitatively with use of Beckman spectrophotometer model DU at $480\;m{\mu}$.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.368-372
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• 2009

The trace polymer and additives in used stripper solutions were analyzed by a combination of Py-GC/MS and ESI-MS. In the comparison of the pyrolysates produced by the pyrolysis of the pure stripper and photoresist at $500{^{\circ}C}$, the presence of novolac polymer in the used stripper was confirmed by the presence of the characteristic peaks of its pyrolysates, such as those of the methylphenol, di-methylphenol and methylenebis(methylphenol) isomers. The intact trace polymer was measured by ESI-MS, which showed the distribution of oligomers at intervals of 120 Da, indicating di-methylphenol to be the repeat unit. Additional MS/MS measurements demonstrated that the end group is methylphenol and the repeat groups are di-methylphenol. Some modified oligomers caused by the methylation or di-methylation of the repeat unit were also identified. Although the polymer is only present at a trace level in the used stripper, these combined analytical methods provided the means to qualify the stripper solution through the identification and structural determination of the polymer.

• Journal of the Korean Institute of Gas
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• v.16 no.2
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• pp.45-51
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• 2012

The MSITs(Minimum Spontaneous Ignition Temperatures) or AITs(Autoignition Temperatures) describe the minimum temperature to which a substance must be heated, without the application of a flame or spark, which will cause that substance to ignite. This study measured the MSITs(Minimum Spontaneous Ignition Temperatures) of n-pentanol+ethylbenzene system by using ASTM E659 apparatus. The MSITs of pure n-pentanol and ethylbenzene were $285^{\circ}C$ and $475^{\circ}C$, respectively. The experimental MSITs of n-pentanol+ethylbenzene system were a in good agreement with the MSIT calculated by the proposed equations with a few A.A.D.(average absolute deviation).

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.35-38
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• 1990

$\alpha$-D-Glucosidase inhibitor purified in a pure form was amorphous powder which gave a single spot at Rf value 0.12-0.71 with various developing solvent systems on silica gel thin layer chromatography, and melting point was 154.3-155.3$^{\circ}C$. It was disolved in water, formic acid and ethylene glycol monoethyl ether, and was very high hygroscopic substance. Biochemical reaction of the substance was positive to phenol sulfuric acid, ninhydrin, silver nitrate-sodium hydroxide, but negative to DNS reagent. Acid hydrolysis gave fructose and acid as sole sugar and amino acid constituents respectively. Moelcular weight of the inhibitor was estimated to be 1,050 by Shphadex G-25 column chromatography.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.257-257
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• 2015

Carbon Capture and Storage with ocean sequestration is being considered as one of the most effective option for reducing the $CO_2$ net flux from atmosphere nowadays. But it is still possible for $CO_2$ substance to leaks out from transport pipeline or from the under seabed storage sites and causing damage to ambient environment. The behavior of liquid $CO_2$ under droplet shape would be strongly affected by the presence of other contaminants such as $SO_2$ comes from processing processes. This presentation shows the behavior in the sea water of pure liquid $CO_2$ droplets as well as droplets that consist of $SO_2$ substances. The study uses computational fluid dynamic models in comparison with experimental data from other previous researchers. Droplet of liquid $CO_2$ is assumed to be released at several depths in deep ocean, with other environmental conditions are set up respectively. All calculations are conducted with many different ratio of contaminant $SO_2$ to provide fundamental data of those particles rising characteristics. The effect of contaminants on the behavior of $CO_2$ droplets would be clearly shown through the results of particle deformation, terminal rising velocity happen due to buoyancy force driving from the difference in density of $CO_2$ substance and ocean water around.

• Journal of environmental and Sanitary engineering
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• v.6 no.1
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• pp.7-25
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• 1991

Until now, pure drinking water grnerally menas the water without taste, odor, general bacteria, coliform, and other exotic substance. Such a definition has been changing recently due to the finding of numerous other inorganic and organic substances unknown to us. 10 years ago, major causes of death were infectious agents and parasites contained in water, but recently, it has become apparent that some substances contained in drinking water cause cancer and heart diseases. We must drink about 2L of water everyday in order to maintain healthy condition. Waters used for drinking include tap water, well water, spring water, filtered water, etc., but the quality of drinking water has more polluted due to the industrial development and population increase. For example, industrial waste waters from industrial plants pollute the water supply sources ; toxic substances contained in the waste waters pollute the ground water sources by penetrating the geological strata, and municipal, livestock, public building waste waters also pollute the water supply sources. Sometimes, the polluted surface waters were announced to be polluted by various kinds of orgainc substance, and it is reported that the pollution of ground water by orga nic substances has few in number but high in its concectration comparing with those of surface water. As the water quality pollution level increases, so the amount of disinfectant also increase. For example, chlorine solution, one of widely used disinfectants, creates trihalomethane(THM), a carcinogen, and halogen compounds. According to Oliver, through chlorine disinfection process, humine substance and chlorine create bolatile organic halide and nonvolatile organic halide by chemical reaction. There are tens or hundreds filtering devices, but filtering principles and maintenance metjhods are different, so their efficiency tests are needed. According to Smith, the effeciency tests aginst over 30 Ameican filtering devices show that 10 devices can remove 85% of volatile organics and further studies on filtered waters are underway. In consideration of important impacts of polluted drinking water on national health, authors studied the state of water quality pollution against tap water used as drinking water, filtration device passed water, ground water, and conserved drinking water ; tested the efficiency of filtration devices for tap water ; tried to sep up the detection method by using ion chromatography based on negative ion and positive ion by using single column, and attemped the simple filtration method for general households.