• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.133-139
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• 2000

In this study, activated carbon was prepared from solid residue after lignin pyrolysis by using zinc chloride as an activation agent. The steam activation method was adopted to manufacture activated carbon from solid residue after lignin pyrolysis. The effect of process operation variables such as activation temperature, activation time and mass of activation agent added to char on the pore structure and specific surface area of the activated carbon was investigated. Activated carbon with high surface area and well-developed pore structure could be prepared, when solid residue after lignin pyrolysis was mixed with zinc chloride of 300 wt% and then the mixture was activated for 1 hour at $1000^{\circ}C$ in a stream of nitrogen.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.907-912
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• 1999

In this study, removal effect of residue pesticides on vegetable and fruit using organic acid salt in alkali solution were investigated by gas chromatography and measurement of detergency. Generally, for the removal methods of residue pesticides and oily pollution were used chemical detergent or organic solvent. Specially, in our experiment, we only used material of food additives and trisodium citrate were superior to other organic acid salt. It was investigated that removal effect of pesticides was superior to chemical detergent.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.610-616
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• 1997

Hepatotoxic cyanobacteria, Microcystis species, were collected from the Nakdong River and we could isolate hepatotoxins, microcystin-LR and microcystin-RR, which are also strong inhibitors of protein phosphatase 1 and 2A. From the microcystins, several microcystin derivatives were synthesized and tested on the mouse toxicity in order to establish the structure-activity relationship. Esterification od carboxyl groups of Glu and MeAsp residue produced nontoxic compounds. However, when we reduced the Mdha residue with sodium borohydride into Ala residue, toxicity was still maintained. Also, the change of guanidyl moiety of Arg residue in microcystin-LR into dimethylpyrimidyl moiety did not change the toxicity of microcystins as well. Thus the carboxyl groups seem to play important roles in binding with protein phosphatase 1 and 2A, whereas Mdha residue and the guanidyl moiety of Arg residue do not.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.1
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• pp.44-49
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• 2013

Hydrogen penetration into a metal leads to damages and mechanical degradations and its content measurement is of importance. For a precise measurement, a sample preparation procedure must be optimized through a series of studies on sample washing and drying. In this study, two-step washing with organic solvents and thermal soaking in inert gas were tried with a rod-shaped, API X65 steel sample. The samples were machined from a steel plate and then washed in acetone and etyl-alcohol for 5 minute each and dried with compressed air. After then, the samples were thermally soaked in a home-made nitrogen gas chamber during 10 minute at different heat gun temperatures from 100 to $400^{\circ}C$ and corresponding temperature range in the soaking chamber was from 77 to $266^{\circ}C$ according to the temperature calibration. Hydrogen residue in the samples was measured with a hot extraction system after each soaking step; hydrogen residue of $0.70{\pm}0.12$ wppm after the thermal soaking at $77^{\circ}C$ decayed with increase of the soaking temperature. By adopting the heat transfer model, decay behavior of the hydrogen residue was fitted into an exponential decay function of the soaking temperature. Saturated value or lower bound of the hydrogen residue was 0.36 wppm and chamber temperature required to lower the hydrogen residue about 95% of the lower bound was $360^{\circ}C$. Furthermore, a thermal desorption spectroscopy was done for the fully soaked samples at $360^{\circ}C$. Weak hydrogen peak was observed for whole temperature range and it means that hydrogen-related contaminants of the sample surface are steadily removed by heating. In addition, a broad peak found around $400^{\circ}C$ means that parts of the hydrogen residue are irreversibly trapped in the steel microstructure.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.985-989
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• 1998

In this study, removal efficiencies of pesticides on apples and peppers with water, dishwashing detergent, and alcoholic disinfectant were investigated by Gas Chromatography. Different conditions of pretreatment for increase of pesticide recovery were investigated for optimum condition. In our experiment, the supelco-STB-608 column and electron capture detector(ECD) were used to analyze pesticides residue. Removal efficiency of pesticide was in the order of alcoholic disinfectant>dishwashing detergent>water.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.639-645
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• 2015

Checksum and residue checking accelerators were implemented on a Nios II core-based platform according to component method, in which the corresponding hardware was implemented with HDL coding, a custom instruction method, in which the instruction set of the processor was extended, and the C2H method, in which the corresponding logic was automatically created by the C2H compiler. The processing results from each accelerator for each algorithm were then examined and compared. The results of the comparison showed that the accelerator implemented with the C2H method is the fastest in terms of the execution time, and the accelerator with custom instruction requires the least add-on from the viewpoint of add-on hardware.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.15 no.3
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• pp.191-199
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• 2011

In this paper, we adopt a position specific scoring matrix as an abstraction of amino acid type to derive two new statistical potentials for protein structure prediction, and investigated its effect on the quality of the potentials compared to that derived using residue specific amino acid identity. For stringent test of the potential quality, we carried out folding simulations of 91 residue A chain of protein 2gpi, and found unexpectedly that the abstract amino acid type improved the quality of the one-body type statistical potential, but not for the two-body type statistical potential which describes long range interactions. This observation could be effectively used when one develops more accurate potentials for structure prediction, which are usually involved in merging various one-body and many-body potentials.

• Carbon letters
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• v.24
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• pp.28-35
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• 2017

We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.515-521
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• 1993

Separation of deasphalted oil from atmospheric residue using n-pentane as a solvent was carried out to obtain the valuable heavy hydrocarbon products that can be used lube base oil. After separation experiments, it is shown that the separation yield of oil from atmospheric residue was dependent on n-pentane density and increased in the critical region of n-pentane. Also, the metal content of separated oil was much lowered when compared with that of atmospheric residue. However, there's slight differences in sulfur removal between above two cases.

• Food Engineering Progress
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• v.15 no.4
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• pp.413-419
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• 2011

For producing a high added-value natural seasoning ingredient, a yeast extract (Yx) was supplemented with a rice protein residue fermented with Bacillus licheniformis (Rfl) or with Bacillus subtilis (Rfs). A rice protein residue was obtained after enzymatic hydrolysis of rice protein which was used for preparing a yeast culture medium. Overall acceptabilities of the supplemented yeast extracts (YxRfl or YxRfs) were higher compared to pure yeast extract. Savory taste like umami was found to increase noticeably by adding a fermented rice protein residue to yeast extract, which was confirmed in taste sensor analysis and in sensory test. Beyond the presence of savory tasting amino acids such as Glu and Asp in a fermented rice protein residue, it is assumed that other soluble peptide fractions remained play an important role in enhancing taste of the supplemented yeast extracts. Thus, the yeast extract added with a fermented rice protein residue could be applied to manufacture a natural seasoning ingredient.