• Korean Journal of Environmental Agriculture
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• v.9 no.1
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• pp.47-52
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• 1990

Metaldehyde Granule (6%) was sprayed 7, 15 and 30 days before harvest at the level of 0.3kg AI/l0a to evaluate metaldehyde residues on the inner and outer part of chinese cabbage. Roots of chinese cabbage were also analyzed. Results were as follows : 1. The amount of free acetaldehyde in chinese cabbage was 0.02-0.18ppm. 2. It was shown that metaldehyde residues in the leaf and root of chinese cabbage increased as the number of treatment increased and treatment period decreased. 3. The metaldehyde residue range in the leaf was in the range of 0.11-1.4ppm 4. The difference of metaldehyde residue on the inner and outer part of chinese cabbage was in the range of 0.01-0.6ppm and the residue on inner parts was slightly higher than outer part. 5. The metaldehyde residue in the root was in the range of 0.04-0.63ppm.

• Korean Journal of Medicinal Crop Science
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• v.24 no.3
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• pp.237-245
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• 2016

Background: Cyanazine is used as a pre-emergent herbicide once during the growing season to control weeds of many upland crops worldwide. This study aimed to establish a method to determined cyanazine residue levels in major medicinal crops by using high performance liquid chromatography-UV detection/mass spectometry (HPLC-UVD/MS). Methods and Results: Cyanazine residue was extracted with acetone from the raw products of four representative medicinal plants - Scutellaria baicalensis, Paeonia lactiflora, Platycodon grandiflorum and Angelica gigas. The extract was diluted with a large volume of saline water and directly partitioned into dichloromethane to remove polar co-extractives in the aqueous phase. It was then purifined using optimized Florisil column chromatography. HPLC analysis conducted using an octadecylsilyl column allowed the successful separation of cyanazine from co-extractives of the samples, and the amount was sensitively quantified by ultraviolet absorption at 225 nm with no interference. The accuracy and precision of the proposed method were validated by conducting recovery experiments on each medicinal crop sample fortified with cyanazine at two concentration levels per crop in triplicate. Conclusions: The mean recoveries ranged from 91.2% to 105.3% for the four representative medicinal crops. The coefficients of variation were less than 10%, irrespective of the sample types and fortification levels. The limit of quantification of cyanazine was 0.02 mg/kg as verified by the recovery experiment. A confirmatory method was performed by liquid chromatography/MS using selected-ion monitoring technique to clearly identify the suspected residue.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.354-358
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• 2005

The study was carried out to investigate dissipation pattern of pesticide residue in/on different varieties of lettuce applied with foliar spraying under greenhouse. The initial deposited amount of alpha-cypermethrin and imidacloprid in/on the crop was entirely corresponded with shape of the crop. Dissipation of deposited pesticide residue was supposed to be related with degradation by sunlight and wash off by watering rather than dilution effect by biomass increase. The crop grouping in leaf vegetables has to be carefully considered even in lettuce for dissipation pattern of pesticide residue; head type and leafy type.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.10 no.1
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• pp.1-6
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• 2004

Amount of residual ink solvent on the packaging materials from Korea, Japan and Europe was measured and compared. The amount of packaging materials from Korea was much higher than that of Japan and Europe. To reduce the residual amounts of ink solvent, aging condition of printed packaging materials including aging time and temperature was modified and evaluated. Aging with high temperature and short time ($60^{\circ}C$ and 24 hours) was more effective for reduction of residual amount of ink solvent than that with low temperature and long time. To find out change of reduction pattern of residual amount of solvent according to plastic packaging material, several monolayer and multilayer packaging materials were selected. Among the monolayer packaging materials, the amount of EVOH and PET was lower than that of polyolefin plastic film including PE and PP. PP/EVOH/PET among the selected multilayer film showed the lowest amount of residual ink solvent on food packaging materials. Result of this research revealed that the residual amount of ink solvent can be reduced by proper selection of aging condition with and by appropriate application of mutilayer plastic film.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.487-494
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• 2017

Spinosad and spinetoram are widely used insecticides for the control of lepidopteran larvae, leaf miners, and thrips; however, they might also have low toxicity toward beneficial insects like bees. Because these pesticides are easily photolyzed by ultraviolet radiation, the QuEChERS method, with its simple pretreatment procedure, is often used for analyzing residues of spinosad and spinetoram. The present study performed a residue analysis using a modified QuEChERS method by pretreating with ammonium salt. The limit of detection (LOD) of the modified method was 0.05 mg/kg and the limit of quantification (LOQ) was 0.25 mg/kg. The coefficient of determination ($R^2$) for the calibration curve was 0.999. Also, we examined any change in the adhesion of spinosad and spinetoram on the plants depending on a spray volume. The adhesion was approximately 70% when the spray volume was increased from 60 L to 120 L per 10 a whereas the adhesion was approximately 37% when the spray volume was increased from 125 L to 250 L. This showed that the amount of adhesion decreased with the higher spray volume. The efficacy result of spinetoram was that over 90% of Frankliniella occidentalis was controlled with the application volume of 125 L per 10 a. Therefore, the result of this study indicates that control of insects is effective and sufficient with a spray volume of 125 L per 10 a in paprika cultivation facilities.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.2
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• pp.157-160
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• 2007

Nymph of the emma field cricket, Teleogryllus emma, were reared on several types of artificial diets. The development period of nymphs were 55.4 days when only a single food, wheat bran, was provided, and it did not show a significant difference compared to the rearing results of the Danong diet and mixed diet. The supplying period of fish meal as the animal feed, the high emergence rates were obtained at 3rd instar with 90% and 4th instar with 100%. For the added amount test, when more than 40% of the diet was added, it confirmed that the insect weight increased. The characteristics of development according to each added amount of the vegetable food (dry bean-curd residue and corn powder) were investigated to minimize the dangers of the degeneration of diet when rearing with a single feed during the $1st{\sim}3rd$ instar period. First, as the added amount of bean-curd residue increased, nymphal development period became longer and the emergence rate became low. With corn powder as the single diet, all died before becoming adult. However, when corn powder was added up to 30%, no difference existed in the breeding results.

• 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 the Society of Disaster Information
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• v.18 no.1
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• pp.182-193
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• 2022

Purpose: By measuring and evaluating the risk of biodiesel through non-volatile residue (NVR) and flash point and explosion limit measurement at a specific temperature according to ASTM test standards, the risk of chemical fire causative substances is identified and a universal evaluation method By derivation and securing the risk-related data of the material, it can be used for the identification and analysis of the cause of the fire, and it can be applied to the risk assessment of other chemical substances Method: In order to measure the risk of biodiesel, it was measured using the non-volatile residue(NVR) measurement method, which measures how much flammable liquid is generated at a specific temperature. Heating was tested by applying KS M 5000: 2009 Test Method 4111. In addition, the flash point was measured using the method specified in ASTM E659-782005, and the energy supply method was measured using the constant temperature method. In addition, the explosion limit measurement was conducted in accordance with ASTM E 681-04 「Standard test method for concentration limits of flammability of chemicals(Vapors and gases)」 test standard. Result: As a result of checking the amount of combustible liquid by the non-volatile residue (NVR)measurement method, the non-volatile residue(NVR) of general diesel when left at 105±2℃ for 3 hours was about 30% (70% of volatile matter) and about 4% of biodiesel. In addition, similar results were obtained for the non-volatile residue(NVR)heating temperature of 150±2℃, 3 hours and 200±2℃ for 1 hour, and white smoke was generated at 200℃ or higher. In addition, similar values were obtained as a result of experimentally checking the explosion (combustion) limits of general diesel, general diesel containing 20% biodiesel, and 100% biodiesel. Therefore, it was confirmed that the flammability risk did not significantly affect the explosion risk. Conclusion: The results of this study suggested the risk judgment criteria for mixtures through experimental research on flammable mixtures for the purpose of securing the effectiveness, reliability, and reproducibility of the details of the criteria for determining dangerous substances in the existing Dangerous Materials Safety Management Act. It will be possible to provide reference data for the judgment criteria for flammable liquids that are regulated in the field. In addition, if the know-how for each test method is accumulated through this study, it is expected that it will be used as basic data in the research on risk assessment of dangerous substances and as a basis for research on the determination of dangerous substances.

• Clean Technology
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• v.27 no.3
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• pp.247-254
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• 2021

In this study, an eco-friendly combustion process of waste 2,4,6-trinitrotoluene (TNT: 2,4,6-trinitrotoluene) was developed, and fundamental data for the quantity of the organic matter in the final combustion residues is presented. Because complete combustion of TNT is not possible theoretically, the combustion process was optimized to reduce organic matter content in the combustion residue by performing measures such as heating time changes, addition of propellant material, and after treatment using a high-temp electrical furnace. From the results, it was confirmed that the organic matter content in the residue could be decreased to 7 ~ 10% with each method. The quantity of the organic matter could be minimized by optimizing the combustion conditions of the process. With only a combustion time increase, the amount of organic matter in the combustion residues was measured at about 9 wt%. The environmental friendliness of the final exhaust gas was also confirmed by real time gas component analyses. In addition, the organic contents could be reduced by a further 2 wt% by applying an additional heat treatment using an external electric furnace after the first incineration treatment. In the combustion process of propellant added waste TNT, it was found that various TNT wastes could be treated using the same eco-friendly protocols because the organic content in the residue decreased in accordance with the amount of propellant. The amount of the organic matter content produced by all these methods fulfilled the requirements under the Waste Management Act.

• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.2
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• pp.287-298
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• 1993

In this study, generation characteristics and distribution situation of the animal fat residue were investigated to identify it's management problems and to propose alternatives for the recycling and final disposal. Generation sources were the meat distribution net-work including about 170 slaughterhouses, 280 meat-packing plants, thousands of meat shops and restaurants etc. The daily total amount of the animal fat residue is about 700 ton/day. More than 60% of the generation sources were concentrated in Seoul metropolitan area. The residue was collected by about 300 men using old-fashioned devices like handcarts, bike and auto bike, transported to the recycling plants by about 60 collection agencies. The residue was processed to produce by-products such as grease, tallow, animal feed ingredient in the recycling plants. At present, however, a great number of unlicensed, and mostly small rendering processors without having pollution control facilities do the unlawful business. These small, old fashioned and unorganized businesses are creating environmental problems by disposing the waste in improper ways such as open burning and dump. Improvement of the distribution network, the large-scale plants, and the estabilishing proper infrastructures were suggested to overcome the problems for the sound fat residues reprocessing industry.