• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.10-24
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• 2021

Purpose: The purpose of this study is to determine the dangers of biodiesel and general diesel mixtures currently used as alternative fuels by equipment (tag method and penski Marten method) and to determine the difference between flash point and combustion point (closed, open) according to test methods. It is intended to be used as a reference material for identification and evaluation of firecausing substances by confirming the risk of mixtures by comparative analysis and measurement, and establishing a risk assessment method for chemical substances. Method: Flash point test method and result treatment were tested based on ASTM and KS M mode, which are tag sealing and pen schematense test methods used as flash point and combustion point test methods for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was a test equipment that satisfies the test standards of KS M 2010 with equipment produced by TANAKA of Japan. The flash point and combustion point were measured, and the flash point according to the test method of biodiesel and general diesel mixture ( Closed, open), and the ignition point of a mixture of biodiesel and general diesel was compared and analyzed for ignition risk compared with conventional diesel. Results: Looking at the experimental results, first, as an analysis of the risk of flammability of the mixture, the flash point of a substance containing 70% biodiesel was found to be about 92℃ based on general diesel with a flash point of 64.5℃, and gasoline and biodiesel or When the biodiesel mixture was synthesized, it was confirmed that the flash point tends to decrease. In addition, the difference between the flash point and the combustion point was analyzed as about 20 ~ 30℃, and when a small amount of gasoline or methanol was mixed, the flash point was lowered, but it was confirmed that the combustion point was similar to that of the existing mixture. Conclusion: In this study, in order to secure the effectiveness of the details of the criteria for judging dangerous materials in the existing Dangerous Materials Safety Management Act, and to secure the reliability and reproducibility of the judgment of dangerous materials, we confirm the criteria for judging the risk of the mixture through an experimental study on flammable mixtures. It will be able to provide reference data for experimental criteria for flammable liquids that are regulated in the field. In addition, if this study accumulates know-how on experiment by test method, it is expected that it can be used as a basis for research on risk assessment and research on dangerous goods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.149-160
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• 2013

The objective of present study was to simultaneously isolate of isoflavone and soyasaponin compounds from the germ of soybean seeds. Soy germ flours were defatted with hexane for 48h at room temperature, and methanolic extracts were prepared using reflux apparatus at $90^{\circ}C$ for 6h, two times. After extraction, extracts were separated with preparative RP-$C_{18}$ packing column ($125{\AA}$, $55-105{\mu}m$, $40{\times}150mm$), and collected 52 fractions were identified with TLC plate (Kieselgel 60 F-254) and HPLC, respectively. Among the identified isoflavone and soyasaponin fractions, isoflavone fractions were re-separated using a recycling HPLC with gel permeation column (Jaigel-W252, $20{\times}500mm$). Final fractions were air-dried, and the purified compounds of two isoflavones (ISF-1-1, ISF-1-2) and four soyasaponins (SAP-1, SAP-2, SAP-3, SAP-4) were obtained. Two isoflavone compounds (ISF-1-1, ISF-1-2) were acid-hydrolyzed for the identification of their aglycones, and confirmed by comparing with 12 types of isoflavone isomers. While the four kinds of soyasaponins were identified by using a micro Q-TOF mass spectrometer in the ESI positive mode with capillary voltage of 4.5kV, and dry temperature of $200^{\circ}C$. Base on the obtained results, it was conclude that ISF-1-1 is the mixture isomers of daidzin (43.4%), glycitin (47.0%), and genistin (9.6%), but ISF-1-2 is the single compound of genistin (99.8% <). On the other hand, soyasaponin SAP-1 is the mixture compounds of soyasaponin A-group (Aa, Ab, Ac, Ae, Af); SAP-2 is soyasaponin B-group (Ba, Bb, Bc) and E-group (Bd, Be); SAP-3 is soyasaponin B-group (Ba, Bb, Bc), E-group (Bd, Be), and DDMP-group (${\beta}g$); SAP-4 is soyasaponin B-group (Ba, Bb, Bc), E-group (Bd, Be), and DDMP-group (${\beta}g$, ${\beta}a$), respectively.

• Research in Plant Disease
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• v.16 no.3
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• pp.259-265
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• 2010

Pepper mild mosaic virus(PMMoV) and Cucumber mosaic virus (CMV) are important pathogens in various vegetable crops worldwide. We have found that hot water extract of Phellinus linteus mycelium strongly inhibit PMMoV and CMV infection. Based on these results, the inhibitor named as 'PLM-WE1' formulated from extract of Phellinus linteus mycelium was tested for its inhibitory effects on PMMoV and CMV infection to each local lesion host plant (Nicotiana glutinosa: PMMoV, Chenopodium amaranticolor: CMV). Pretreatment effect of PLM-WE1 against infections of each virus (PMMoV and CMV) to local host plant was measured to be 99.2% to PMMoV and 80.3% to CMV, and its permeability effect was measured to be 45.0% to PMMoV and 41.9% to CMV. Duration of inhibitory activity of PLM-WE1 against PMMoV infection on N. glutinosa was maintained for 3 days at 75% inhibition level and CMV infection on C. amaranticolor maintained for 3 days at 62% inhibition level. Inhibitory effects on systemic host plants of PLM-WE1 were measured to be 75~85% to PMMoV and 75% to CMV. Under electron microscope, PMMoV particles were not denatured or aggregated by mixing PLM-WE1. It is suggested that the mode of action of PLM-WE1 differ from that of inactivation due to the aggregation of viruses. The methanol extract of P. linteus mycelium was sequentially partitioned with haxane, ethyl acetate, BuOH and $H_2O$. The $H_2O$ fraction was showed high activity than the other fractions. The active compound was isolated with a partial acid hydrolysis, fractional precipitation with ethanol. The inhibitory effect of the precipitate isolated from 70% ethanol fraction was 99.1% to PMMoV and 88.0% to CMV. The structure of isolated compound was determined by $^1H$-NMR and $^{13}C$-NMR. This compound was identified as a polysaccharide consisting alpha or beta-glucan.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.85-99
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• 2014

Sulfonylurea (SU)-resistant weeds of eight annual weeds, Monochoria vaginalis, Scirpus juncoides and Cyperus difformis, etc., and four perennial weeds, Scirpus planiculmis, Sagittaria pigmaea, Eleocharis acicularis and Sagittaria trifolia as of 2013 since identification Monochoria korsakowii in the reclaimed rice field in 1998. And the resistant Echinochloa oryzoides to ACCase and ALS inhibitors has been confirmed in rice fields of the southern province, Korea in 2009. In the beginning, the M. vaginalis, S. juncoides and C. difformis of these SU-resistant weeds were rapidly and individually spreaded in different fields, however, these resistant weeds have been occurring simultaneously in the same filed recently. The resistant biotype by weed species demonstrated about 10-to 1,000-fold resistance, based on $GR_{50}$ values of the SU herbicides tested. And the resistant biotype of E. oryzoides to cyhalofop-butyl, pyriminobac-methyl, and penoxsulam was about 14, 8, and 11 times more resistant than the susceptible biotype base on $GR_{50}$ values. The products and applied area of SU-included herbicides have been increased rapidly, and have accounted for about 69% and 96% in Korea, respectively. In Korea, the main cause of SU-resistant weed is extensive use of these herbicides. The top ten herbicides by applied area were composed of all SU-included herbicides by 2003. The concentrated and successive treatment of ACCase and ALS inhibitors for control of barnyardgrass in rice led up to the resistance of E. oryzoides. Also, SU-herbicides like pyrazosulfuron-ethyl and imazosulfuron which effective to barnyardgrass can be bound up with the resistance of E. oryzoides. The ALS activity isolated from the resistant biotype of M. korsakowii to SU-herbicides tested was less sensitive than that of susceptible biotype. The concentration of herbicide required for 50% inhibition of ALS activity ($I_{50}$) of the SU-resistant M. korsakowii was 14-to 76-fold higher as compared to the susceptible biotype. No differences were observed in the rates of [$^{14}C$]bensulfuron uptake and translocation. Acetolactate synthase (ALS) genes from M. vaginalis resistant and susceptible biotypes against SU-herbicides revealed a single amino acid substitution of proline (CCT), at 197th position based on the M. korsakowii ALS sequence numbering, to serin (TCT) in conserved domain A of the gene. Carfentrazone-ethyl and pyrazolate were used mainly to control SU-resistant M. vaginalis by 2006 in Korea. However, the alternative herbicides such as benzobicyclone, to be possible to control simultaneously the several resistant weeds, have been developing and using broadly, because the several resistant weeds have been occurring simultaneously in the same fieled. The top ten herbicides by applied area in Korea have been occupied by products of 3-way mixture type including herbicides with alternative mode of action for the herbicide resistant weeds. Mefenacet, fentrazamide and cafenstrole had excellent controlling effects on the ACCase and ALS inhibitors resistant when they were applied within 2nd leaf stage.

• Journal of the Korean Vacuum Society
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• v.20 no.6
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• pp.395-402
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• 2011

The nanomechanical properties of fully lithiated and unlithiated silicon nanowire deposited on silicon substrate have been studied with atomic force microscopy. Silicon nanowires were synthesized using the vapor-liquid-solid process on stainless steel substrates using Au catalyst. Fully lithiated silicon nanowires were obtained by using the electrochemical method, followed by drop-casting on the silicon substrate. The roughness, derived from a line profile of the surface measured in contact mode atomic force microscopy, has a smaller value ($0.65{\pm}0.05$ nm) for lithiated silicon nanowire and a higher value ($1.72{\pm}0.16$ nm) for unlithiated silicon nanowire. Force spectroscopy was utilitzed to study the influence of lithiation on the tip-surface adhesion force. Lithiated silicon nanowire revealed a smaller value (~15 nN) than that of the Si nanowire substrate (~60 nN) by a factor of two, while the adhesion force of the silicon nanowire is similar to that of the silicon substrate. The elastic local spring constants obtained from the force-distance curve, also shows that the unlithiated silicon nanowire has a relatively smaller value (16.98 N/m) than lithiated silicon nanowire (66.30 N/m) due to the elastically soft amorphous structures. The frictional forces of lithiated and unlithiated silicon nanowire were obtained within the range of 0.5-4.0 Hz and 0.01-200 nN for velocity and load dependency, respectively. We explain the trend of adhesion and modulus in light of the materials properties of silicon and lithiated silicon. The results suggest a useful method for chemical identification of the lithiated region during the charging and discharging process.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.46-54
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• 2022

Known for its effectiveness in weight loss and diabetes prevention, Gymnema sylvestre products can be found in the US, Japanese, and Indian markets. However, the recommended dosage or safety of these products has not yet been proven. Therefore, development of an analytical method for detecting the content of Gymnema sylvestre in food products is required. Accordingly, this study proposes an analysis method that can examine Gymnema sylvestre in food using LC-ESI-MS/MS and KASP (Kompetitive Allele-Specific PCR) markers. In LC-ESI-MS/MS, a simultaneous analysis method for gymnemic acid and deacylgymnemic acid was optimized using negative ionization mode, and its validation test was completed for solid and liquid samples. In addition, KASP markers were prepared by finding the specific SNP of G. sylvestre in ITS2 and matK through DNA barcodes. The two KASP markers returned positive FAM fluorescence result when combined with G. sylvestre, and this aspect was confirmed in raw G. sylvestre as well. The applicability of the method was tested on 21 different food and healthy functional products containing G. sylvestre purchased on the internet. As a result, although there was a difference in the ratios of gymnemic acid and deacylgymnemic acid in LC-ESI-MS/MS, the index component was detected in all 21 products samples. In the KASP analysis, 9 products returned positive FAM result, and the rest of the products were found to be containing G. sylvestre extract. This study is the first study to use the dual system of LC-ESI-MS/MS and KASP for the analysis of G. sylvestre. The study has confirmed that these two methods are applicable to the examine G. sylvestre content in food products.

• Korean Journal of Weed Science
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• v.31 no.2
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• pp.119-133
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• 2011

Sulfonylurea (SU)-resistant weeds include seven annual weeds such as Monochoria vaginalis, Scirpus juncoides and Cyperus difformis, etc., and three perennial weeds of Scirpus planiculmis, Sagittaria pigmaea and Eleocharis acicularis as of 2010 since identification Monochoria korsakowii in the reclaimed rice field in 1998. The Echinochloa oryzoides resistant to acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitors has been confirmed in wet-direct seeding rice field of the southern province, Korea in 2009. In the beginning of occurrence of SU-resistant weeds the M. vaginalis, S. juncoides and C. difformis were rapidly and individually spreaded in different fields, however, theses resistant weeds have been occurring simultaneously in the same filed as time goes by. The resistant biotype by weed species demonstrated about 10- to 1,000-fold resistance, base on $GR_{50}$ (50% growth reduction) values of the SU herbicides tested. And the resistant biotype of E. oryzoides to cyhalofop-butyl, pyriminobac-methyl, and penoxsulam was about 14, 8, and 11 times more resistant than the susceptible biotype base on $GR_{50}$ values. In history of paddy herbicides in Korea, the introduction of SU herbicides including besulfuron-metyl and pyrazosulfuron-ethyl that control many troublesome weeds at low use rates and provide excellent crop safety gave farmers and many workers for herbicide business refreshing jolt. The products and applied area of SU-included herbicides have been rapidly increased, and have accounted for about 69% and 96%, respectively, in Korea. The top ten herbicides by applied area were composed of all SU-included herbicides by 2003. The concentrated and successive treatment of ACCase and ALS inhibitors for control of barnyardgrass in direct-seeded rice led up to the resistance of E. oryzoides. Also, SU-herbicides like pyrazosulfuron-ethyl and imazosulfuron which are effective to barnyardgrass can be bound up with the resistance of E. oryzoides. The ALS activity isolated from the resistant biotype of M. korsakowii to SU-herbicides tested was less sensitive than that of susceptible biotype. The concentration of herbicide required for 50% inhibition of ALS activity ($I_{50}$) of the SU-resistant M. korsakowii was 14- to 76-fold higher as compared to the susceptible biotype. No differences were observed in the rates of [$^{14}C$]bensulfuron uptake and translocation. ALS genes from M. vaginalis resistant and susceptible biotypes against SU-herbicides revealed a single amino acid substitution of proline (CCT), at 197th position based on the M. korsakowii ALS sequence numbering, to serin (TCT) in conserved domain A of the gene. Carfentrazone-ethyl and pyrazolate were used mainly to control SU-resistant M. vaginalis by 2006, the early period, in Korea. However, the alternative herbicides such as benzobicyclone, to be possible to control simultaneously the several resistant weeds, have been developing and using broadly because the several resistant weeds have been occurring simultaneously in the same filed. The top ten herbicides by applied area in Korea have been occupied by products of 3-way mixture type including herbicides with alternative mode of action for the herbicide resistant weeds. Mefenacet, fentrazamide and cafenstrole had excellent controlling effects on the ACCase and ALS inhibitors resistant when they were applied within 2 leaf stage.