• The Plant Pathology Journal
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• v.23 no.2
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• pp.45-50
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• 2007

Genetic diversity among selected isolates of Macrophomina phaseolina, a causal agent of charcoal rot (stalk rot) disease in sorghum was studied using PCR-RAPD markers. A set of ten isolates, from ten different rabi sorghum genotypes representing two traditional sorghum growing situations viz., Dharwad- a transitional high rainfall region and Bijapur- a semi-arid low rainfall region in South India. From a set of 40 random primers tested, amplicon profiles of 15 were reproducible. A total of 149 amplicon levels, with an average of 9.9 bands per primer, were available for analysis, of which 148 were polymorphic (99.3%). It was possible to discriminate all the isolates with any of the 15 primers employed. UPGMA clustering of data indicated that the isolates shared varied levels of genetic similarity within a range of 0.14 to 0.72 similarity coefficient index and it was suggestive that grouping of isolates was not related to sampling location in anyway. A high level of genetic heterogeneity of 0.28 was recorded among the isolates.

• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.185-188
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• 2003

In order to enhance shoot elongation and rooting of Anthurium andreanum 'Atlanta' in vitro, 15mL of liquid media containing various concentrations of activated charcoal, sucrose and MS salts were added in same vessels after small shoots were induced from the calli on mudium supplemented with 10.0mg/L BA and 0.1mg/L 2.4-D. The post-supplying of 15mL liquid medium containing MS macro and micro elements, 30g/L sucrose and 5.0∼10.0g/L activated charcoal was significantly stimulated the shoot elongation and rooting of regenerated shoots from calli. The medium addition was also resulted in the enhanced soil survival, elongation and rooting of plantlets in cultural soil mixed with perlite and vermiculite(1 : 1)

• Journal of Conservation Science
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• v.5 no.1 s.5
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• pp.87-93
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• 1996

This study was carried out to Identify wood and charcoal segments, which were excavated in 1994 at the Seohaean highway construction site along the western coast of Korea ; Tuntaeri, Hwasunggun. We identified the objects excavated at the fire places of the Tuntaeri dwelling sites (early Koryo period ; A. D. $11\~12C$) ; charcoal pieces and 1 wood segment, which was used for the handle of a metal hook. Chestnut(Castanea crenata), deciduous oaks(Quercus spp.) and maple(Acer app.) were identified from the charcoals, whereas the wood segment as willow species(Salix spp.). These species seem to represent warm and wet climate in the middlewest Korea during $11\~12C$.

• Carbon letters
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• v.1 no.2
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• pp.87-90
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• 2000

Porous carbon from charcoal filled polypropylene composites were prepared and their mechanical properties were evaluated. In preparing the composites, crosslinking agent (sodium benzonate) were used in order to improve the bonding force between matrix and fillers. In this study, the effects of charcoal powder and sodium benzonate concentration on the mechanical properties and interface phenomena on the composites were evaluated. The mechanical properties of composites increased progressively with the decrease of filler loading. In the case of addition of the crosslinking agent into the composite, the mechanical properties were increased and showed maximum value at the 3 wt% concentration of sodium benzonate. According to the result of the TGA, the weight loss of composite according to crosslinking agent was not observed and initial thermal degradation temperature of composite reinforced charcoal was located at $390^{\circ}C$.

• The Journal of Engineering Geology
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• v.6 no.3
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• pp.131-136
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• 1996

Attenuation characteristics of AF/MA motions which involve high frequencies were investigated through pencil-lead fracture tests on a fine-grained granite specimen. For the study, calibrated six transducers were employed to detect the signals and the pencil-lead was fractured as a step unloading force to generate AE/MA signals. The arnplitude AE/MA waves is affected by the relative orientation of source and transducer as well as the source distance. The attenuation constant for Charcoal granite is obtained as 1.058 which could be applied for a given ray-path regardless of the relative orientation of source and transducer.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.419-424
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• 1989

The effects of browning Products (BP) from Kanjang(soy sauce) and charcoal on the degradation of aflatoxin $B_1(AFB_1)$ in Kanjang and its model system were studied. Approximately 60% of $AFB_1$ was degraded in the presence of 0.05% BP at pH 7 of phosphate buffer after 2 days of incubation at $30^{\circ}C$. The mutagenicity of the $AFB_1$ which reacted with the BP was decreased to about 50% and 70% in Salmonella typhimurium TA98 and TA100 strains, respectively (p<0.05). When a few pieces of charcoal were added to home made Kanjang, $AFB_1$ was quite stable for 5days at $30^{\circ}C$, however, about 80% of $AFB_1$ was removed when the charcoal was either in distilled water or in 20% of NaCl solution after 2 days of incubation. Activated carbon instead of the charcoal removed $AFB_1$ completely in the all samples under the same conditions.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.98-103
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• 1995

In this paper, a method is presented for finding an optimal temperature control pattern in microwaveoven using genetic algorithm. Power spectrum of temperature variance of charcoal is obtained and oven system modeling with fuzzy-neural-network is explained. Fan on/off timing is converted to strings in gene pool and then genetic iterations make the power spectrum of simmulated temperature variance of microwave oven closer to that o charcoal.

• Journal of the Korean Wood Science and Technology
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• v.35 no.4
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• pp.21-28
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• 2007

To analyze the changes in pH and elemental content ratio of wood charcoal and in FT-IR spectra of their surfaces, wood charcoals carbonized from Pinus koraiensis were used. pHs of wood charcoals carbonized from Pinus koraiensis at 300 and $400^{\circ}C$ were 5-27 and 6.80, respectively, whereas they were between 9.25~10.35 for the wood charcoals manufactured between $500{\sim}900^{\circ}C$ From the changes in the elemental ratios of Pinus koraiensis wood charcoal by increasing carbonization temperature, carbon (C) contents increased by elevating the carbonization temperature with the decreasing in content ratios of O and H. The largest changes in the ratio was found between the carbonization temperature 400 and $500^{\circ}C$. Ratios of C, O, H of the wood charcoal manufactured at 300 and $400^{\circ}C$ were 67.7, 28.9, 3.0% and 72.2, 24.9, 2.5%, respectively, while those at $500{\sim}900^{\circ}C$ were between 83.3~90.5, 13.6~9.0, 2.7~0.3%. The surface functional groups of Pinus koraiensis wood charcoals were determined by comparison of FT-IR spectra of the wood powder and the wood charcoal carbonized with the wood powder. The functional groups on the surface of wood charcoals carbonized at 300 and $400^{\circ}C$ were considered to be acidic groups like Lactone, Lactol, Carboxylic acid, Carboxylic anhydride, whereas Pyrone types could be the major functional groups for the wood charcoals carbonized between 500 and $900^{\circ}C$.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.266-274
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• 2014

To extend the understanding of the pyrolysis mechanism of wood, we have investigated wood dust charcoal and condensate of volatile organic compounds (VOC) obtained during the pyrolysis of red pine (Pinus densiflora Sieb. et Zucc.) at $180{\sim}450^{\circ}C$ using elemental analysis, IR and GC/Mass. The effect of activation process on the charcoal structure also has been studied by comparing elemental analysis and IR data of charcoal carbonated at $600^{\circ}C$ and charcoals activated at $750^{\circ}C$. The results show that pyrolysis of wood has mainly started near at $240^{\circ}C$ and its chemical components did not changed much up to $270^{\circ}C$. However, the element contents and IR spectra drastically changed at $300^{\circ}C$. The fact that IR peaks related to the aromatic ring of lignin are observed in the charcoal pyrolized at $450^{\circ}C$ indicates that a small part of lignin still remains at this temperature. The chemical structure of the activated charcoal seems almost unaffected by the activation time.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.732-744
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• 2020

In this study, a torrefaction of Quercus serrata to manufacture a molded charcoal was performed, investigated material properties, fuel characteristics, and performed a quantitative analysis of hazardous gases which occur during a combustion process. In addition, a molded charcoal in market was selected as a control group, and a comparative analysis was performed. As a result, the higher heating value (HHV) of the torrefied specimen was about 14% higher than that of molded charcoal, and its ash content was about 51 times lower. Moreover, after performing a quantitative assessment of hazardous gases (carbon monoxide, nitrogen oxide, and sulfur dioxide) which were produced when each specimen was combusted for 900 seconds in an enclosed chamber, it was confirmed that the maximum value of generated amount of carbon monoxide on the torrefied specimen was about 50 times lower than that of the existing molded charcoal. Therefore, it was shown that the torrefied specimen produced in this study had a higher heating value than the molded charcoal in the market, and a very low amount of carbon monoxide generated during the combustion process.