• Applied Biological Chemistry
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• v.34 no.4
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• pp.373-378
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• 1991

The skin and fleshy substance on the net fiber of sponge-gourd fruit pressed mechanically was removed with 0.2% NaOH solution in $3{\sim}5$ hours. The treatment of 0.2% NaOH with 0.02% Monopol(non-ionogenic polyoxethylen derivative) as surfactnat and with 0.1% $Ca(OCl)_2$ as bleaching agent enhanced the effect to remove the fleshy substance and improve the quality of net fiber. Also, the wet hardness and tensile strength of net fiber were controlled by the crosslinkage of the fiber with glu tardialdehyde, glyoxal, and formalin, respectively. The net fiber was stable on the acid and alkaline solutions. Also the range of temperature to degradate the fiber was $338{\sim}385^{\circ}C$. These values indicated a fair stability. The improved net fiber can be used for raw material of bath, dish washing, oil and gas filter, and many kinds of decorations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.467-472
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• 1991

In order to investigate the changes of lipid ingredient and fatty acid content in flint corn by a growth process, total lipids from flint corn(Zea may l.) were extracted, purified and fractionated into three lipid classes (neutral lipid ; NL, glycolipid ; GL, phospolipid ; PL) by silicic acid column chromatography (SACC). Non-polar lipid ingredients and fatty acid contents were determined by thin layer chromatography (TLC) and gas chromatography (GC). And non-polar lipid ingredients were quantitatived by TLC scanner. The crude oil among proximare composition increased 2.74% to 4.43% and NL and PL were fractionated by SACC increased 48.5% to 86.02%, 1.01% to 2.73%, respectively. But GL decreased 50.4% to 11.25%. Neutral lipid ingredients identified monoglyceride, were 1.1~3.7%, 11.9~16.1%, 2.3~4.2%, 16.7~21.5% and 58.5~63.6%, respectively. The major fatty acids of NL were linoleic (48.9~61.0%), oleic(22.3~34.2%), palmitic (10.3~11.7%) acids and stearic, linolenic acids were also detected as minor components. The ratio of total unsaturated fatty acid to total saturated fatty acid presented a higher percentage of 5.87~6.34. The physico-chemical characteristics of flint corn lipids were presented as specific gravity presented 0.920, refractive index 1.468, saponification value 191.2, unsaponificable matter 0.97%, acid value 0.58 and iodine value 124.6, respectively.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.215-224
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• 2018

Influences of the magnetic field on 5, 10 and 15 wt% (1.5, 3 and 4.5 M) HCl solution behaviour, which has widespread applications in petroleum well acidizing, were investigated in various conditions. Differences in the pH of magnetized hydrochloric acid compared to that of normal hydrochloric acid were measured. Taguchi design of experimental (DoE) method were used to model effects of the magnetic field intensity, concentration, velocity and temperature of acid in addition to the elapsed time. The experimental results showed that the magnetic field decreases [$H^+$] concentration of hydrochloric acid up to 42% after magnetization. Increasing the magnetic field intensity (with 28% contribution), concentration (with 42% contribution), and velocity of acid increases the effect of magnetic treatment. The results also demonstrated that the acid magnetization was-not influenced by the fluid velocity and heating. It was also displayed that the acid preserves its magnetic memory during time. The optimum combination of factors with respect to the highest change of [$H^+$] concentration was obtained as an acid concentration of 10% and an applied magnetic field of 4,300 Gauss. Due to the reduction of HCl reaction rate under the magnetization process, it can be proposed that the magnetized HCl is a cost effective and reliable alternative retarder in the matrix acidizing of hydrocarbon (crude oil and natural gas) wells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1033-1037
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• 2001

Garlic oleoresins were made by extracting with four solvents of methanol, methyl acetate hexane and acetone from chopped garlic, respectively, and the volatile compounds of each extract were separated by gas chromatography installed with polar (supelcowax-10$^{TM}$) and nonpolar (HP-5) capillary columns, respectively, and identified by matching mass data of mass selective detector and Kovat\`s retention index with references. The numbers of the volatile compounds identified the garlic oleoresin by polar and nonpolar columns from in garlic oleoresins were 41 and 32, respectively. In polar column, 13 pyrans, 11 sulfur-containing compounds 6 furans 2 alcohols and 2 heterocyclic compounds were identified. In nonpolar column, 11 sulfur-containing compounds 5 acids 3 furans and eugenol were identified. The major sulfur-containing compounds identified from the oleoresins were 3, 3'-thiobis-1-propene, methyl 2-propenyl disulfide, dimethyl trisulfide, di-2-prnpenyl-trisulfide, 2-thiophenecarboxylic acid. The amount of these sulfur-containing compounds isolated from the oleresins were more abundant in polar column than in nonpolar column. The most efficient solvent for extracting volatile compounds of garlic was methanol but the most useful solvent for extracting sulfur-containing compounds was methyl acetate of less polarity.y.

• Applied Biological Chemistry
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• v.26 no.2
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• pp.90-96
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• 1983

To study the composition of silkworm pupae oil, lipid of silkworm pupae was separated into two fractions, ether extractable and 85% methanol extractable, and the lipid components of each fraction were analyzed by using silicic acid column, thin layer chromatography and gas chromatography. Silkworm pupae contains 35.4% crude fat (dry-basis) of which consists 34.4% diethyl ether-extract and 0.9% of 85% methanolextract. The diethyl ether-extract contained 96.1% of neutral lipid, 2.9% of glycolipid and 1.0% of phospholipid while methanol-extract was consisted of 47.4% of neutral lipid, 14.6% of glycolipid and 38.1% of phospholipid. The major components of phospholipid were phosphatidyl glycol(41.0%), and phosphatidyl choline(28.2%) and phosphatidyl ethanolamine(21.2%) in the diethyl ether-extract and phosphatidyl glycol(48.4%), phosphatidyl inositol(22.8%) and phosphatidyl choline(17.9%) in the methanol-extract. The major fatty acids of the total lipid were oleic acid(33.5%), linolenic acid(31.0%) and palmitic acid(23.1%).

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.1
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• pp.137-142
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• 2014

Industrial control system (ICS) is a computer based system which are typically used in nation-wide critical infra-structure facilities such as electrical, gas, water, wastewater, oil and transportation. In addition, ICS is essentially used in industrial application domain to effectively monitor and control the remotely scattered systems. The highly developed information technology (IT) and related network techniques are continually adapted into domains of industrial control system. However, industrial control system is confronted significant side-effects, which ICS is exposed to prevalent cyber threats typically found in IT environments. Therefore, cyber security vulnerabilities and possibilities of cyber incidents are dramatically increased in industrial control system. The vulnerabilities that may be found in typical ICS are grouped into Policy and Procedure, Platform, and Network categories to assist in determining optimal mitigation strategies. The order of these vulnerabilities does not necessarily reflect any priority in terms of likelihood of occurrence or severity of impact. Firstly, corporate security policy can reduce vulnerabilities by mandating conduct such as password usage and maintenance or requirements for connecting modems to ICS. Secondly, platfom vulnerabilities can be mitigated through various security controls, such as OS and application patching, physical access control, and security software. Thirdly, network vulnerabilities can be eliminated or mitigated through various security controls, such as defense-in-depth network design, encrypting network communication, restricting network traffic flows, and providing physical access control for network components.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.50-63
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• 2007

The development of domestic plant specific emission factors is very important to estimate reliable national emissions management. This study, for the reason, was carried out to obtain advances emission factor for Carbon Dioxide ($CO_2$) by source-specific emission tests from the iron and steel industry sector which is well known as one of the major sources of greenhouse gases ($CO_2$). Emission factors estimated in this study were compared with those of IPCC for evaluation and they were found to be of similar level in the case of $CO_2$. There was no good information available on $CO_2$ plant specific emission factors from the iron and steel industry in Korea so far. The major emission sources of $CO_2$ examined from the iron and steel manufacturing precesses were a hot blast stove, coke oven, sintering furnace, electric arc furnace, heating furnace, and so on. In this study, the concentration of $CO_2$ from the hot blast stove process was the highest among all processes. The $CO_2$ emission factors for a ton of Steel and Iron products (using B-C oil) were estimated to be 0.315 $CO_2$ tonne (by Tier 3 method) and 4.89 $CO_2$ tonne. In addition, emission factor of $CO_2$ for heating furnace process was the highest among all process. Emission factors estimated in this study were compared with those of IPCC for evaluation and they were found to be of similar level in the case of $CO_2$.

• Clean Technology
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• v.17 no.1
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• pp.56-61
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• 2011

In this study, hydrocarcking of vacuum residue was carried out in an autoclave reactor at $450^{\circ}C$ and $500^{\circ}C$ with a commercial catalyst (HDM) and the quantitative product distributions were analyzed by GC-SIMDIS method or simple distillation. During catalytic hydrocracking, thermal cracking also occurred together with catalytic cracking and the higher conversion and selectivity of gasoline and naphtha were obtained at high reaction temperature. GC-SIMDIS and simple distillation revealed different results for the analysis of products produced at different hydrocracking temperatures; almost same results were obtained for the product produced at $500^{\circ}C$ but different ones for the product produced at $450^{\circ}C$. In the analysis of product produced at $450^{\circ}C$, the GC-SIMDIS showed that a main product was VGO while a main product in the simple distillation was diesel, which implies that the simple distillation for the $450^{\circ}C$ reaction was not accurate due to thermal cracking of the product by the simple distillation.

• Environmental and Resource Economics Review
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• v.22 no.2
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• pp.215-250
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• 2013

The term, "resource curse", is widely used to describe how countries rich in natural resources, such as oil, natural gas, and certain minerals, are unable to utilize that wealth to boost their economies. Contrary to previous research on the topic, this study has demonstrated that natural resources have a strong positive correlation with a country's economy. It likewise confirmed that this result is robust with broad sets of exogenous variables, and that the positive impact of natural resources on the economy remains significant with the inclusion of capital stock per worker. In this sense, it is doubtful that resource curse actually exists in the long-run. On the other hand, this study tested whether the quality of institutions has any relation with natural resource endowments if the positive effect of natural resource endowments on the gross domestic product (GDP) is adequately controlled for. In contrast to findings of Alexeev and Conrad (2009), if the former Soviet Union (FSU) countries are included, it seems that there might be a negative and statistically significant relationship between large endowments of natural resources and the quality of institutions. However, this negative relationship loses its significance and some positive albeit insignificant relationships are confirmed in a considerable number of cases when the FSU countries are excluded in the sample. That is, the negative relationship results from the inclusion of the FSU countries. This result is believed to happen by a temporary coincidence of events, a natural resource windfall and political and economic instability during the transition of the FSU countries. Therefore, the argument that resource abundance harms the institutional quality is confirmed to be a little groundless.

• Journal of Soil and Groundwater Environment
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• v.13 no.4
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• pp.62-68
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• 2008

The Low Temperature Thermal Desorption (LTTD) System equipped with a soil transfer unit, a rotary kiln, RTO, cyclones and a bag filter etc. was developed. The LTTD system was designed to be economically operated using LPG as a fuel and recirculating the discharged gas from the LTTD system through RTO. For the performance test of LTTD system the soil contaminated with light and heavy oils (2,690 mg TPH/kg soil) and with particle sizes below 50 mm was fed into the rotary kiln of LTTD system at 7$m^3$/hr with retention time of 15 minutes. Operation temperatures of LTTD system for the removal of soil TPH were $567^{\circ}C$ and $692^{\circ}C$. The residual TPH after treatment was 46 mg/kg and 32mg/kg respectively at each temperature condition, which shows high TPH removal efficiencies of the developed LTTD as 98.3% and 98.9%.