• KSBB Journal
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• v.20 no.4
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• pp.317-322
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• 2005

Various recovery methods were investigated to maximize hemicellulose recovery from lignocellulosic material hydrolyzed by pure water. The pretreatment conditions of water hydrolysis were $170\~180^{\circ}C$ and 1 hour of reaction time. The percentage of hemicellulose solubilized increased as the temperature increased from 170 to $180^{\circ}C$. However, significant decomposition of sugar was observed at temperature of $180^{\circ}C$. From the results of water hydrolysis, the total amount of glucan in solid residue and liquid hydrolyzate was close to the total glucan in the original biomass. For hemicellulose, however, there was a significant difference between both contents. To prove this difference, various recovery methods were proposed. From the total sugar accountability (sugar in liquid + sugar in solid), it was confirmed that hemicellulose recovery in the hydrolyzate was increased if the product including both hydrolyzate and solid residue was physically stimulated by such as heating and ultrasound irradiation. This indicated that, in commercial scale processes that much bigger substrate sizes are used and a sufficient amount of leaching solvent can not be used after pretreatment, a significant amount of oligomers could be trapped in the solid matrix.

• Journal of Energy Engineering
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• v.14 no.4 s.44
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• pp.268-276
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• 2005

Vacuum Residue (VR) combustion tests were carried out with a 20 kg/hr (fuel feed rate) small scale reactor. The nozzle used was a steam atomized, internal mixing type. Compared to heavy oil, vacuum residue used in this work is extremely high viscous and contains high percentages of sulfur, carbon residue and heavy metals. To ignite atomized VR particles, it was necessary to preheat the reactor, and it has been done with LP gas. The axial and radial gas temperature, major species concentrations and solid sample were analyzed when varying the fuel feed rate. The main reaction zone of atomized VR-air flame in a reactor was anticipated within about 1 m from the burner tip by considering the profiles oi gas temperature, species concentration and particle size measured along with the reactor. At downstream, the thermally, fully developed temperature distribution was obtained. SEM photographs revealed that VR carbon particles collected from the reactor are porous and have many blow-holes on the particle surface.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.285-294
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• 2005

This study was conducted to investigate the extraction method for the determination of organochlorine, organophosphorus and synthetic pyrethroid pesticide residues in beef fat by gas chromatography-mass selective detector(GC-MSD). Twenty one pesticide residues in fat were determined using a simple and rapid procedure based on solid- phase extraction(SPE) clean-up cartridges with octadecyl $(C_{18})-bonded$ porous silica, florisil, $10\%$ deactivated florisil. a tandem $C_{18}$ and florisil and a tandem $C_{18}$ and $10\%$ deactivated florisil. Solvent-solvent extraction using acetonitrile was not satisfied to eliminate fat interference for pesticide residue analysis by GC-MSD, and the recoveries of the method in fat ranged from 16.2 to $57.3\%$ except DDT$(83.2\%)$. The recoveries of SPE methods using a tandem $C_{18}$ and Florisil was $59.6\~123.8\%$ except fenitrothion $(135.2\%)$. the SPE method was verified the satisfactory performance of pre-treatment for pesticide residues analysis in fat by GC-MSD. The efficiency of florisil deactivated with $10\%$ water has been not proved significantly on recoveries of pesticide residues in fat.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.237-242
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• 2005

This experiment was carried out to develop the fast and simple method for pesticide residue analysis by using solvent free solid injector (SFSI) and to validate the efficiency of the method developed for the residue analysis of the endocrine disruptor-like pesticides such as endosulfan, metribuzin, trifluralin and vinclozolin. The samples after freeze drying were sealed in glass capillary tubes and then introduced into the heated injector of gas chromatogaphy. The required pre-heating times were 1 min for endosulfan and trifluralin, 5 min for vinclozolin, and 10 min for metribuzin. The detection limits of endosulfan in chinese cabbages, metribuzin in lettuces, trifluralin in spinachs and vinclozolin in hot peppers were 0.05, 0.1, 0.05 and 0.05 ng, respectively and their recoveries were ranged from 74%, $98{\sim}107%$, $86{\sim}95%$ and $94{\sim}95%$, respectively. The detected level of metribuzine residue in field lettuce samples by using the SFSI was 0.6 ng/mg.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.638-643
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• 1996

The efficiency of dewatering of soybean milk residue was improved by hydraulic pressing after pH adjustment to 4.5 with organic acids such as acetic and lactic acids. Water content of raw soybean milk residue was reduced from 80% to 72% by pressing after pH adjustment, while only to 78% by the conventional hydraulic press. The water content of the residue after pH adjustment was further reduced to 63% by hydraulic pressing with ohmic heating. The pH adjustment facilitated separation of cake from the filter cloth and reduced the solid content of the expressed liquid from 10 to 3%.

• Resources Recycling
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• v.23 no.5
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• pp.28-35
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• 2014

The basic properties of cow and chicken manure such as proximate analysis and element analysis were estimated and the comparison to energy characteristics of carbonization residue between cow and chicken manure was evaluated. The optimum carbonization condition of cow and chicken manure was decided by total heating value of carbonization residue which was expressed by multiplying low heating value by yield. The optimum carbonization conditions for carbonization time and temperature can be decided by 15 min, and $350^{\circ}C$ for chicken manure, and 20 min, and $300^{\circ}C$ for cow manure. At the optimum carbonization conditions, low heating values for the carbonization residue of cow and chicken manure are evaluated by 4,378kcal/kg, and 3,462kcal/kg, respectively. The residues of cow manure were satisfied with the standard of solid fuel product. However, the residue of chicken should be improved by materials changes to be used as a renewable energy source.

• Toxicological Research
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• v.12 no.2
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• pp.163-169
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• 1996

The focus of this study was to investigate the suitable analytical methods for measurement of sulfamerazine and its metabolite in shrimp hepatopancreas and tail tissue, in addition to the methods for the optimization of solid-phase extraction cartridge conditions and the elucidation of sulfamerazine concentrations in aqueous buffer using HPLC with UV and EC detectors. Compared with UV detector the EC detector appears to be 10 times more sensitive than that of the UV detector. After the shrimp was exposed to 10 ppm sulfamerazine, the accumulation levels of sulfamerazine and its metabolite in tail tissue, which is edible portion, were considerably lower than 0.1 ppm. The data indicate that sulfamerazine continues to be a candidate for use at levels of sulfamerazine concentration used in aquaculture of shrimp.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.448-452
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• 2001

An Experimental study was carried out to develop a simple method of processing copper waste sludge which is produced by PBC manufacturing. The procedure is based on leaching of wet sludge in 2N H$_2$SO$_4$, and the solid / liquid ratio is controlled approximately at 1/10. The recovery of copper is 85.4%, and pH of the leachate is 3.20. Adding ammonia solution into leachate forms ammine, and hydroxide compounds derived from other impurities in leachate at pH 10. The hydroxide compound can be treated by ferrite process, and the product is a stable oxide compound. Then the ammine solution is heated to evaporate ammonia, and the copper hydroxide is formed. Heating at 8$0^{\circ}C$by aeration, copper hydroxide is transformed into copper oxide with a purity of 98.4%. This process can recover most copper from sludge and the residue can be stabilized by the formation of a stable oxide compound which is not hazardous to environment.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.79-84
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• 2015

A new cecropin-like antimicrobial peptide (Px-CLP) gene was isolated from the immunechallenged larvae of the swallowtail butterfly, Papilio xuthus, by employing annealing control primer (ACP)-based GeneFishing PCR. The full-length cDNA of Px-CLP is 310 nucleotides encoding a 70 amino acid precursor that contains a putative 22-residue signal peptide, a 4-residue propeptide, a presumed 37-residue mature peptide, and an uncommon 7-residue acidic pro-region at the C-terminus. The deduced amino acid sequence of Px-CLP showed significant identities with other Lepidopteran cecropin D type peptides. RT-PCR revealed that the Px-CLP transcript was detected at significant level after injection with bacterial lipopolysaccharide (LPS). The peptides with or without C-terminal acidic sequence region were synthesized on-solid phage and submitted to antibacterial activity assay. The synthetic 37-mer peptide (Px-CLPa), which removed C-terminal acidic sequence region, was showed exclusively antibacterial activity against E. coli ML35; meanwhile, a 44-mer peptide (Px-CLPb) with C-terminal acidic peptide region was not active. This result suggests that Px-CLP is produced as a larger precursor containing a C-terminal pro-region that is subsequently removed by C-terminal modification.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.203-213
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• 2005

Oxytetracycline, tetracycline, chlortetracycline and doxycycline in honey were separated by solid phase extraction (SPE) and determined with high performance liquid chromatography (HPLC) with UV/Visible detector. Analysis was carried out using following conditions: XTerra $C_8$ column $(3.9\times150mm\;i.d. 5{\mu}m)$, mobile phase composed of 0.01M oxalic acid : methanol : acetonitrile (820 : 80 : 100, v/v/v), isocratic pump at a flow rate of 0.9 ml/min. and $50{\mu}l$ of injection volume, UV/Visible detector with wavelength of 360nm. The calibration curves of four tetracyclines showed linearity $(\gamma^2>0.999)$ at concentration range of $100\~1,000 ng/ml$. The recoveries in fortified honey represented more than $70\%$ with low coefficient of variation $(<10\%)$ for concentration range of four tetracyclines. The detection limits for oxytetracycline, tetracycline, chlortetracycline and doxycycline were 13.8, 14.6, 26.2 and 24.9ng/g in acacia honey. respectively. We also monitored tetracyclines residue in domestic honey [n : 38, acacia (20), wild flower (18) ] and foreign honey [n=22, legally distributed (13), illegally distributed (9)] using modified Charm II screening and HPLC confirmation methods. Seven of the 60 samples $(11.7\%)$ were suspect positive using modified Charm II screening test. Chlortetracycline residue was found in one foreign honey (illegally distributed) tested at concentrations of 0.22 ppm. Conclusively, for more effective control of tetracyclines used in beekeeping should be further survey for residues in honey and also national guidelines (maximum residue limit : MRL) and methods should be obligatory.