• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.32-39
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• 1998

This study was performed to develop jumbo granules floated and spreaded on the water surface after application, having low production and formulation cost, and safe to environment for paddy herbicides and to establish the formulation recipe. The jumbo granules of azimsulfuron with molinate(0.075+7.5%) was formulated by KCl as water soluble carrier and paraffin oil as solvent to impose the floating and spreading force to granules. That showed 100% of total granules to be floated on and spreaded upto the water surface within 25 minutes after application. Change in carriers, surfactants and pH did not affected to improve the time-course degradation of azimsulfuron in jumbo granules, but salt formation of azimsulfuron added by 1.15M solution of NaOH a little. Addition of N-methyl acrylate and modification of formulation process affected decrease in degradation of azimsulfuron upto 1.2, 2.1, and 7.2% after 2, 6 and 12 weeks under storage at $40{\pm}2^{\circ}C$, respectively, which showed the establishment of formulation recipe of the jumbo granules.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.132-139
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• 2002

This study was carried out to investigate the effects of aging and soil texture on composting of diesel-contaminated soil. The soils used for this study were silt loam and sand. Target contaminant, diesel oil, was spiked at 10,000mgTPH/kg of dry soil. Aging times of diesel-contaminated soils were 15days and 60days, respectively. Fresh diesel-contaminated soil was also investigated. Moisture content was controlled to 70% of soil field capacity. Mix ratio of soil to sludge was 1:0.3 as wet weight basis. Temperature was maintained at $20^{\circ}C$ Volatilization loss of TPH was below 2% of initial concentration. n-Alkanes lost by volatilization were mainly by the compounds of C10 to C17. Diesel in contaminated soil was mainly removed by biodegradation mechanism. First order degradation rate constant of TPH in sandy soil was ranged from 0.081 to 0.094/day, which is higher than that in silt loam(0.056-0.061/day). From fresh to 60day-aged soils, there was little difference of TPH biodegradation rate between the soils. Carbon recovery ranged from 0.61 to 0.89. TPH degradation rate was highly correlated with $CO_2$ production rate.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.785-790
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• 2000

The effect of formaldehyde treatment of solvent and mechanical extracted cottonseed meal on the performance, digestibility and nitrogen balance was assessed in lambs. Four total mixed rations viz., A, B, C and D containing 40% untreated and treated solvent and mechanical extracted meal were prepared. Sixteen male lambs with average BW of 20-22 kg were randomly allocated to experimental rations and were fed individually during ninety days growth trial. The treatment of solvent extracted cottonseed meal resulted in a linear decrease in ruminal protein degradation. Maximum decrease (64%) in protein degradation was observed at 4 h incubation time with 0.3% formaldehyde treatment. Highest daily BW gain was observed in lambs fed on rations Band D compared to lambs fed on rations A and C. Daily BW gain was higher on rations having 0.3% for fromaldehyde treated cottonseed meals. Higher DM digestibility was observed on ration D compared to other rations. Higher (p<0.05) CP and CF digestibility was observed on rations Band D compared to rations A and C. Nitrogen retention as % age of nitrogen intake was (p<0.05) higher for lambs fed rations B and D compared to rations A and C. Similar pattern was observed for nitrogen retention as percent of nitrogen absorbed. The present study suggested that oil extraction methods of cottonseed did not alter their meal utilization in lambs, however, formaldehyde (0.3%) treatment of meals enhanced its efficiency for growth, digestibility and nitrogen balance in lambs.

• Advances in environmental research
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• v.2 no.3
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• pp.229-243
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• 2013

Coagulation-flocculation (CF) was tested coupled with an aerobic biofilter to reduce total petroleum hydrocarbon (TPHs) concentration and toxicity from petrochemical wastewater. The efficiency of the process was followed using turbidity and chemical oxygen demand (COD). The biofilter was packed with a basaltic waste (tezontle) and inoculated with a bacterial consortium. Toxicity test were carried out using Lactuca sativa var. capitata seeds. Best results for turbidity removal were obtained using alum. Considerable turbidity removal was obtained when using Opuntia spp. COD removal with alum was 25%, for Opuntia powder it was 36%. The application of the biofilter allowed the removal of 70% of the remaining TPHs after 30 days with a biodegradation rate (BDR) value 47 $mgL^{-1}d^{-1}$. COD removal was slightly higher with BDR value 63 $mgL^{-1}d^{-1}$. TPH kinetics allowed a degradation rate constant equal to $4.05{\times}10^{-2}d^{-1}$. COD removal showed similar trend with $k=4.23{\times}10^{-2}d^{-1}$. Toxicity reduction was also successfully achieved by the combined treatment process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.21-25
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• 2002

The contribution of lipid to thermal flayer generation from glucose-protein reaction was accomplished by isolating flavor compounds from casein-glucose (CG)and casein-glucose-coin oil (CGL) which were stored for 2 and 4 weeks at 6$0^{\circ}C$ and then reacted at 16$0^{\circ}C$ for 1hr. The volatiles from the reactant mixtures were isolated by a solvent extraction method with methylene chloride and analyzed by gas chromatography and gas chromatography-mass spectrometry. Pyrazine, methylpyrazine, 2,5-dimethylpyrazine, 2-dimethylpyrazine ,2-ethy-5- methyIpyrazine and 2-acetylpyrrole originated from interaction of thermal degradation of casein and lipid oxidation were identified in the CGL samples. It was also found that 3-methyl-1-butanol, 2-cyclopene-1,4-diode, heptanal, nonanal, and 2-heptanone were derived from lipid source. Two additional fatty acids, heptanoic acid and octanoic acid were also identified in the CGL samples. 5-Hydroxymethyl-2-furfural, the most abundant volatile, was responsible for the formation of sugar degradation product. The results suggested that the presence of lipid in the samples had more effect on the contribution of volatile formation of glucose-protein thermal reaction than the absence of lipid in the samples.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.53-62
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• 1992

Material can be degraded by using it for a long service under the high temperature and pressure circumstances, Therefore, material degradation can affect the strength of mechanical structures. At present, the life prediction of the degraded structures is considered as an important technical problem. In this paper, the degraded 21/4Cr-lMo steel is the material used for about 10 years around 400.deg. C in an oil refinery plant. The recovered one was prepared out of the above degraded steel by heat treatment for one hour at 650.deg. C. The degradation effect was investigated through the tension test, Hardness test and Charpy impact test. On the smooth surface material, the fatigue crack initiation, growth and coalescence stages of the distributed small cracks were investigated with photographs, and the crack length and density were measured. The measuring results were analyzed by quantative and statistical methods.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.157-163
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• 2001

Mycolic acid-containing gram-positive bacteria, so called nocardioform actinomycetes, have become a great interest to environmental microbiologists due to their metabolic versatility, multidegradative capacity and potential for bioremediation of priority pollutants. For example, Rhodococcus rhodochrous N75 was able to metabolize 4-methy1catechol via a modified $\beta$-ketoadipate pathway whereby 4-methylmuconolactone methyl isomerase catalyzes the conversion of 4-methylmuconolactone to 3-methylmuconolactone in order to circumvent the accumulation of the 'dead-end' metabolite, 4-methylmuconolactone. R. rhodochrous N75 has also shown the ability to transform a range of alkyl-substituted catechols to the corresponding muconolactones. A novel 3-methylmuconolactone-CoAsynthetase was found to be involved in the degradation of 3-methylmuconolactone, which is not mediated in a manner analogous to the classical $\beta$-ketoadipate pathway but activated by the addition of CoA prior to hydrolysis of lactone ring, suggesting that the degradative pathway for methylaromatic compounds by gram-positive bacteria diverges from that of proteobacteria. Mycobacterium sp. Strain PYR-l isolated from oil-contaminated soil was capable of mineralizing various polyaromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, pyrene, fluoranthrene, 1-nitropyrene, and 6-nitrochrysene. The pathways for degradation of PAHs by this organism have been elucidated through the isolation and characterization of chemical intermediates. 2-D gel electrophoresis of PAH-induced proteins enabled the cloning of the dioxygenase system containing a dehydrogenase, the dioxygenase small ($\beta$)-subunit, and the dioxygenase large ($\alpha$)-subunit. Phylogenetic analysis showed that the large a subunit did not cluster with most of the known sequences except for three newly described a subunits of dioxygenases from Rhodococcus spp. and Nocardioides spp. 2-D gel analysis also showed that catalase-peroxidase, which was induced with pyrene, plays a role in the PAH metabolism. The survival and performance of these bacteria raised the possibility that they can be excellent candidates for bioremediation purposes.

• Polymer(Korea)
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• v.34 no.6
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• pp.547-552
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• 2010

Biodegradable polymers have gained enormous attentions in the pharmaceutical and biomedical applications, especially in drug delivery. In this work, we report the synthesis and characteristics of high molecular weight polyoxalate with ~75000 Da. Hydrolytic degradation kinetics and degradation products were characterized by nuclear magnetic resonance and gel permeation chromatography. Polyoxalate is a semicrystalline and thermally stable polymer with a glass transition temperature of ${\sim}35^{\circ}C$, which is suitable for drug delivery applications. The hydrophobic nature of polyoxalate allows it to be formulated into nanoparticles and encapsulate drugs using a conventional oil-in-water emulsion/solvent displacement method. Polyoxalate nanoparticles also exhibited excellent cytotoxicity profiles. It can be suggested that polyoxalate has great potential for numerous biomedical and pharmaceutical applications.

• Journal of Conservation Science
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• v.31 no.4
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• pp.457-476
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• 2015

This study is expected to present instructions and analysis of Modern Dancheong pigments by its physical characteristics. Search pigments currently used and experiments proper mixing ratio of Jangdanyuksaek(Incarnadine). Samples are made by based on presented a mixture ratio which is less exfoliation, cracks and color change. And put into accelerated weathering test and ultraviolet ray degradation test. As a result in case of Jidang($TiO_2$) Rutile type is superior in discoloration and durability. Rutile type makes color difference remarkably because of oil absorption difference while mixing with Jangdan. Water paints which are used as a alternative present yellowness which means water paints lack in durability. whiting should be taken carefully as it has high brightness after degradation.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.457-476
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• 2016

This was investigated on the major issues and research trends regarding the heat-treatment of woods through literature reviews. The principal heat-treatment technologies utilized for industrial purposes include the Plato-process (Netherlands), the Retification process (France), the OHT-process (Germany), and the Thermowood Process (Finland). Factors that mainly influence the heat-treatment process are the wood species, process temperature, processing time, and the heating medium (air, steam, vacuum, N2, oil, etc.). Researches on investigating the optimal conditions with these process conditions being the variables stand as the mainstream. Heat-treated woods present dimensional stability improvement, but mass loss and strength reduction, a wide variations for decaying inhibition, and insufficient resistance against mold, wood borer, and termites. For further improvement in respects of durability or resistance to biological degradation, necessity to search for more suitable heat treatment process and processing conditions fit for each wood species has been suggested. Exploiting new ways to utilize heat-treated wood and extending its range of use have been considered to be important matters that need more effort put into for the sustainable and sound environment as well as saving the wood resources.