• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.212-217
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• 2021

This experiment was conducted to compare effects of summer pruning at different times and dormant pruning on shoot growth and yield of northern highbush blueberry. Using 7 (2018) to 9 (2020) years old 'Duke' bushes grown in 180 L containers, summer pruning was treated on June 20 (around 30 days after harvest), July 20, and August 20 consecutively in both 2018 and 2019 removing 30% of the total woods, while dormant pruning (conventional) was on January 20 in both 2019 and 2020. Summer pruning reduced shoot growth the following year, especially when treated in late summer. Total shoot length per bush decreased to 47%, 37%, and 33% on October 15, 2020 in June, July, and August pruning, respectively, compared with that of dormant pruning. Summer pruning at different times in 2018 and 2019 did not affect berry characteristic in the following year. Yield per bush was not significantly changed in 2019, but it decreased by 21 to 38% in 2020 in the summer pruning treatments compared with 2.9 kg of the dormant pruning. It was concluded that consecutive summer pruning in 'Duke' under unheated plastic house could weaken the shoot growth with reducing yield.

• Journal of Climate Change Research
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• v.3 no.3
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• pp.211-224
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• 2012

Technology for energy recovery from waste can reduce the greenhouse gas emissions. So recently, there are several companies using RDF, RPF, WCF instead of using only coal fuel and it's part of the fuel on the increase. In this study, we developed Wood chip fuel $CO_2$ emission factor through fuel analysis. It's moisture content is 23%, received net calorific value is 2,845 kcal/kg, and received basis carbon is 34%. The result of emission factor is $105ton\;CO_2/TJ$, it's 5.9% lower than 2006 IPCC guideline default factor $112ton\;CO_2/TJ$. The gross GHG(Greenhouse gases) emissions of plant A is $178,767ton\;CO_2 eq./yr$, and Net GHG emissions is $40,359ton\;CO_2 eq./yr$. Therefore, the reduction of GHG emissions is $138,408ton\;CO_2/yr$ through using WCF, and I accounts for 77% of all GHG emissions.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.27-35
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• 2004

Recalcitrant 4-t-Octylphenol used as a surfactant was subjected to the biodegradation with wood rot fungi, Basidioradulum molare and Schizopora paradoxa. Two fungi were grown in the culture medium containing various concentrations of 4-t-Octylphenol in order to investigate their resistance against 4-t-octylphenol Schizopora paradoxa was reached to the full growth within 14 incubation days in the concentration of more than 200 ppm of 4-t-Octylphenol, while Basidioradulum molare showed the inhibitory mycelium growth as the concentration was increased Schizopora paradoxa and Basidioradulum molare biodegraded 95% and 36% of initial concentration of 4-t-Octylphenol at first incubation day, respectively. However, the biodegradation capability reached to more than 95% after 3 incubation days. During the biodegradation of 4-t-Octylphenol, the activity of manganese dependent peroxidase was induced by the addition of 4-t-Octylphenol in the culture medium of Schizopora paradoxa, but that of laccase was maximal before the addition. The reduction of estrogenecity was assayed by MCF-7 cell proliferation test and measurement of pS2 mRNA expression. The level of pS2 mRNA was decreased down to the level of baseline at first incubation day. Also, estrogenecity of 4-t-Ocrylphenol completely disappeared after treatment with supernatant by Schizopora paradoxa and Basidioradulum molare from first incubation day of culture down to the levels of vehicle.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.183-187
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• 2021

Appropriate pruning is very important for southern highbush blueberries cultivated in a heated plastic house to control their severe crowding within the bush canopy after harvest. Pruning treatments at different times were evaluated to find out an appropriate pruning time to southern highbush 'Scintilla' cultivation with heating. Seven-year-old (2018) bushes, grown in 180-L containers, were summer-pruned on May 20 (35-39 days after harvest) and June 20, or dormant-pruned on December 20 (5 days before flowering), consecutively in both 2018 and 2019 removing 30% of the total woods. May pruning activated occurrence of shoots the following years, increasing number of shoot by 17 to 49% and total shoot length by 18 to 32% compared with those of the dormant pruning. Fruit characteristic was not significantly affected by different pruning times the previous year. The first year pruning treatment did not influence the yield the following year, but the second year consecutive May pruning significantly increased yield per bush by 7% compared with the dormant pruning. The results indicated that summer pruning in May could be favorable to promote shoot growth and to maintain stable yield.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.172-179
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• 2002

In this study, two materials treated with a flame retardant were examined for their fire resistance. The first, MDF (medium density fiberboard) was overlaid by an oak sliced veneer, which was either treated by soaking in a 6wt.% solution of flame retardant chemicals (pentabromine-chlorinated paraffin) or non-treated and then was coated with either a flame retardant polyurethane coating or with a common polyurethane coating. The second material, Pinus koraiensis penal was either treated by a spray treatment using a flame retardant solution or non-treated and then was coated with either a flame retardant polyurethane coating or with a common polyurethane coating. Pentabromine-chorinated paraffin chemicals were added (6 part of urethane resin) as the flame retardant chemicals in the polyurethane coatings. In the fire resistance test, the th𝜃(℃·min) decreased with the flame retardant treatment or/and the flame retardant coatings, compared to the untreated sample Weight loss (%) decreased with the flame retardant treatment or/and the flame retardant coatings. The ignition time (sec.) increased and the residual flame time (sec.) decreased with the flame retardant treatment or/and flame retardant coatings. Therefore, the flame retardant treatment or/and flame retardant polyurethane coatings have excellent incombustibility.

• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.25-33
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• 2002

Improvement of density profile and sound absorption capability of particleboard was attempted. Three types of hot pressing methods examined ; flat-platen pressing method (A-type pressing), hot pressing in forming box (B-type pressing), and hot pressing set up jagged caul in forming box (C-type pressing). The raw materials were larch(Larix leptolepis (S, et. Z.) Gorden) shavings, phenol formaldehyde resin, and the particleboard perforated with stair type. The physical and mechanical properties such as specific gravity, bending strength (MOR), internal bonding strength (IB) and sound absorption coefficients were examined. The results are summarized as follows : 1) The MOR and internal bonding strength of the board pressed in forming box were higher than those of flat-platen pressed board. 2) The minimum density to average density ratio in thickness direction which pressed in forming box showed about 923%, in the case of 35 mm commercial particleboard and 50 mm flat-platen pressed board, its values showed about 66.4% and 865% respectively. 3) Sound absorption coefficients of the particleboard perforated with stair type were higher than those of flat-plated pressed board and commercial particleboard.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.1-8
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• 2022

With the spread of COVID-19 worldwide, non-face-to-face services have grown rapidly, but at the same time, the problem of plastic waste is getting worse. Accordingly, eco-friendly policies such as carbon neutrality and sustainable circular economy are being promoted worldwide. Due to the high demand for eco-friendly products, the packaging industry is trying to develop eco-friendly packaging materials using PLA and PBAT and create new business models. On the other hand, Ulva australis occurs in large quantities in the southern seas of Korea and off the coast of Jeju Island, causing marine environmental problems. In this study, lactic acid was produced through dilute acid pretreatment, enzymatic saccharification, and fermentation processes to utilize Ulva australis as a new alternative energy raw material. In general, seaweeds vary in carbohydrate content and sugar composition depending on the species, harvest location, and time. Seaweed is mainly composed of polysaccharides such as cellulose, alginate, mannan, and xylan, but does not contain lignin. It is difficult to expect high extraction yield of the complex polysaccharide constituting Ulva australis with only one process. However, the fusion process of dilute acid and enzymatic saccharification presented in this study can extract most of the sugars contained in Ulva australis. Therefore, the fusion process is considered to be able to expect high lactic acid production yield when a commercial-scale production process is established.

• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.32-39
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• 2023

Using the logarithmic methods and the generalized method of moments (GMM), this study developed carbon storage equations for maple trees (Acer palmatum Thunb.) planted in an urban settlement area. A total of 20 maple trees of various ages and diameters were destructively harvested to determine their dry weight and carbon concentration by component. The allometric equations with DBH and DBH²×H as independent variables were developed to estimate the carbon storage for each tree component. The carbon concentration of tree components was the highest in stem wood (49.8%) and lowest in stem bark (46.5%). Allometric equations to estimate the carbon storage of tree components (stem, root, aboveground, and total) showed a similar coefficient of determinations (R²) between the allometric equations of the logarithmic method (0.7494-0.9036) and the GMM (0.7085-0.8847). However, the R² values of the leaves and branches were in the range of 0.3027 to 0.6380, lower than those of the R² of the other tree components. These results indicate that the carbon storage of maple trees growing in urban settlement areas can be efficiently predicted from the equations of GMM methods in the case of a small sample size or the heteroscedasticity of logarithmic equations.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.291-300
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• 2022

In this study, the physical properties of the medium and changes in the wood chemical composition of the sawdust were investigated during the cultivation of oak mushroom sawdust bags, and the following results were obtained. After inoculation, the weight of the medium decreased during the incubation period. It is determined that this is not due to evaporation of moisture containing the medium or decomposition of sawdust, but to decomposition of rice bran, a low molecular substance added to the medium. It was confirmed that the moisture content of the medium was steadily increased during incubation, and it was estimated that the organic substrates such as rice brane in the medium was decomposed by mycelium, and water, one of the decomposition products of organic substrates, caused an increase in the moisture content of the medium. Along with the increase in the harvest of oak mushrooms, the proportion of organic substances such as holocellulose and lignin, the main components of the wood cell wall of sawdust, steadily decreased. In particular, the degradation characteristics of the wood cell wall component of shiitake, which is a white rot fungi, were confirmed by higher lignin reduction rate than that of holocellulose. On the other hand, ash, which is an inorganic material, increased with an increase in the number of mushroom harvests. The increase in the amount of ash in the medium may have been due to the decrease in the organic matter content such as holocellulose and lignin.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.529-533
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• 2023

The fundamental electrochemical properties and adsorption capabilities of the carbonized product derived from coffee grounds, a prevalent form of lignocellulose abundantly generated in our daily lives, have been extensively investigated. The structure and morphology of the resultant carbonized product, obtained through a carbonization process conducted at a relatively low temperature of 600 ℃, were meticulously examined using a scanning electron microscope. Raman spectroscopy measurements yielded a relative crystallinity (D/G ratio) of the carbon product of 0.64. Electrical measurements revealed a linear ohmic relationship within the carbonized product. Furthermore, the viability of utilizing this carbonized material as an anode in lithium-ion batteries was evaluated through half-cell charge/discharge experiments, demonstrating an initial specific capacity of 520 mAh/g. Additionally, the adsorption performance of the carbon material towards a representative dye molecule was assessed via UV spectroscopy analyses. Supplementary experiments corroborated the material's ability to adsorb a distinct model molecule characterized by differing surface polarity, achieved through surface modification. This article presents pivotal findings that hold substantial implications for forthcoming research endeavors centered around the recycling of lignocellulose waste.