• Journal of Power Electronics
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• v.13 no.3
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• pp.497-506
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• 2013

This paper proposes a new method to improve the available battery capacity in electric vehicles by connecting lead-acid batteries with lithium-ion battery in parallel to supply power. In addition, this method combines the discharge characteristics of batteries to improve their efficiency and lower their cost for electric vehicles. A lithium-ion battery set is used to connect with N sets of lead-acid batteries in parallel. The lead-acid battery supplies the initial power. When the lead-acid battery is discharged by the load current until its output voltage drops to the cut-off voltage, the power management unit controls the lead-acid battery and changes it to discharge continuously with a small current. This discharge can be achieved by connecting the lead-acid battery to a lithium-ion battery in parallel to supply the load power or to discharge its current to another lead-acid or lithium-ion battery. Experimental results demonstrates that the available capacity can be improved by up to 30% of the rated capacity of the lead-acid batteries.

• Fire Science and Engineering
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• v.25 no.1
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• pp.57-62
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• 2011

The flash point is one of the most significant combustion properties of flammable liquids in industrial processes when evaluation process safety, In this paper, Cleveland open cup tester is used to measure the flash points for the two binary systems (n-propanol + formic acid and acetic acid + propionic acid). The measured flash points were compared with the values calculated by the Raoult's law and the optimization method using van Laar and Wilson equations. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• Korean Journal of Environmental Agriculture
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• v.4 no.2
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• pp.114-117
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• 1985

A new method for micro-quantification of abscisic acid from plant tissue is described. GLC-ECD method of abscisic acid pertafluorobenzyl ester synthesized by reaction of plant extract with pentafluorobenzyl bromide showed higher sensitivity than that of abscisic acid methyl ester, and the detection limit of abscisic acid by the described method was as low as 5 pg.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.253-256
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• 2006

The purpose of this study was to develop a gas chromatographic (GC) method to analyze fatty acids in milk fat with a single injection. The single-injection GC method we developed for analyzing fatty acid composition can separate a wide range of fatty acid methyl esters from butyric acid to docosahexaenoic acid. It separated 6 isomers of 18:1 (cis-6, cis-9, cis-11, trans-6, trans-9 and trans-11), 4 isomers of 18:2 (cis-9-cis-12, trans-9-trans-12, cis-9-trans-12 and trans-9-cis-12), and 4 isomers of conjugated 18:2 (cis-9- trans-11, trans-9-cis-11, cis-10-trans-12 and trans-10-cis-12).

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.13-14
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• 1957

Th-determination by the sebacic acid method was compared with the hydrogen peroxide method. The former is a little more complicated than the latter in the operation and at the same time it requires careful pH adjustment, but the time needed for determination could be decreased greatly by the former. As a result of the comparison between both methods we confirmed that, within ${\pm}$0.08 ${\%}$ of error, when $ThO_2$ was contained $5{\%}$ in the sample, we could use the sebacic acid method with an half time of that required for the hydrogen peroxide method. Thorium in Monazite sand was also determined by both methods and compared. In the case we found, too, that if we permitted the maximum error of ${\pm}$0.08 ${\%}$, we could prefer the sebacic acid method.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.204-208
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• 2006

This study is to describe continuous-flow analysis (CFA) for the determination of nitrate using hydrazine-copper in plant material and to test precision of this method compared with that of methods, which are RQflex method and salicylic acid method. Samples were leaves of watermelon, cucumber, melon and tomato. Nitrate values measured by the RQflex method were greater than those measured by CFA or salicylic acid method. The correlation of nitrate values between those measured by CFA and salicylic acid method was $R^2=0.9671$, and those measured by CFA between those measured by RQflex method was $R^2=0.9739$. Recovery rate of nitrate added to tissue extract by CFA method was $99.7{\pm}0.25%$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.3
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• pp.211-215
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• 2000

Lipid extraction preceding fatty acid methyl esters preparation for gas-liquid chromatography is time-consuming and cumbersome. We performed one-step extraction/methylation method with a mixture of methanol-heptane-benzene-DMP-H$_2$SO$_4$ without prior fat extraction. The simultaneous digestion and lipid transmethylation takes place at 8$0^{\circ}C$ in a single phase. After cooling till room temperature, two phases are formed. The upper one of the phases contains the fatty acid methyl esters ready for GLC. The fatty acid composition of major industrial crops obtained by the one step extraction/methylation method (method 1 and 2) was almost identical with the fatty acid composition of the pure fats extracted with hexane by the Soxtec instrument (method 3). Due to its simplicity, speed, and reduced organic solvent the one-step extraction/methylation method (method 1 and 2) should be useful to determine overall fatty acid composition, especially in situations where many samples have to be analyzed.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.51-56
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• 1982

An automatic method for the determination of total amino acid in tobacco was studied. This method makes use of the reaction of 2, 4, 6-Trinitrobenzene sulfonate with amino acid. Results obtained with this simple and rapid method agreed with those obtained with the offical method.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.15-18
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• 1965

Fatty acid components of the Chestnut gall wasp (Dryocosmus kuriphilus YASUMATSU) were analyzed by the method of gas chromatogrphy at various developmental stages. 1. The fatty acids identified at each stage are as follows : Larva stage : acetic acid , benzoic acid and capric acid. Prepupa stage : acetic acid, benzoic acid and capric acid. Pupa stage : acetic acid, benzoic acid and capric acid. 2. Through the development of the wasp, there were large amount of acetic acid.

• Journal of Pharmaceutical Investigation
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• v.4 no.1_2
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• pp.46-54
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• 1974

A new spectrophotemetric method was estalished for the determination of oleic acid. This method is based on the 1,2-dichloroe-thane extraction of the ion-pair formed between methylene blue and oleic acid. But the absorbance of an ion-pair in the 1,2-dichloroe-thane layer was variable with the temperature, the ion-pair was extracted back into a diluted hydrochloric acid solution. The maximum absorbance of the acid extract observed at $660m{\mu}$ and a lineal relationship was observed from the initial amount over the range of $50-800{\gamma}/ml$ of oleic acid in the aqueous phase. The composition ratio of the ion-pair formed between methylene blue and oleic acid was determined to be 2 : 1 by both the mole ratio and continuous variation methods.