• Title/Summary/Keyword: Wood drying

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Combustion Characteristics of Wood Specimens Treated with Methylenepiperazinomethyl-Bis-Phosphonic Acid (Mn+)s (메틸렌피페라지노메틸-비스-포스폰산 금속염으로 처리된 목재 시험편의 연소특성)

  • Jin, Eui;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.28 no.3
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    • pp.55-61
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    • 2014
  • This study was performed to test the combustive properties of pinus rigida specimens treated with methylpiperazinomethyl-bis-phosphonic acid $M^{n+}$ ($PIPEABPM^{n+}$)s and methylpiperazinomethyl-bis-phosphonic acid (PIPEABP). Pinus rigida Plates were painted in three times with 15 wt% $PIPEABPM^{n+}s$ and PIPEABP solutions at the room temperature respectively. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with $PIPEABPM^{n+}s$ showed the lower speed to peak mass loss rate ($MLR_{peak}$), (0.104~0.121) g/s than that of PIPEABP plate. In adition, the specimens treated with $PIPEABPM^{n+}s$ showed both the lower total smoke release rate (TSRR), (224.4~484.0) $m^2/m^2$ and $CO_{mean}$ production (0.0537~0.0628) kg/kg than those of PIPEAB plate. Especially, for the specimens treated with $PIPEABPM^{n+}$ by reducing the smoke production rate except 2nd-smoke production rate (2nd-SPR), (0.0254~0.02270) g/s treated with $PIPEABPNi^{2+}$, 2nd-SPR (0.0117~0.0146) g/s was lower than that of PIPEABP plate. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated $PIPEABPM^{n+}s$ in the virgin plate.

Biodegradation of Kraft Lignins by White-Rot Fungi(I) -Lignin from Pitch Pine- (백색부후균에 의한 크라프트 리그닌의 분해(I) -리기다소나무 리그닌-)

  • 김명길;안원영
    • Journal of Korea Foresty Energy
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    • v.17 no.1
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    • pp.56-70
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    • 1998
  • This study was carried out to investigate the structural characteristics of kraft lignin and the wood degrading characteristics, the productivity of ligninolytic enzymes and the enzymatic degradation of kraft lignin by white-rot fungi. To purify kraft lignin, precipitation of kraft pulping black liquors of pitch pine meal was done by titration with lN $H_{2}SO_{4}$ reaching to pH 2, and isolation of the precipitates done by centrifugation. The isolated precipitates from pitch pine were redissloved in lN NaOH, reprecipitated by titration with lN $H_{2}SO_{4}$, washed with deionized water, and kept ofr analysis after freeze drying. Fractionation of the precipitates in solution by successive extraction with $CH_{2}Cl_{2}$ and MeOH, and the fractionates were named SwKL, SwKL I, SwKL II, and SwKL III for pitch pine kraft lignin. The more molecular weights of kraft lignin increased, the less phenolic hydroxyl groups and the more aliphatic hydroxyl groups. Because as the molecular weights increased, the ratio of etherified guaiayl/syringyl(G/S ratio) and the percentage were increased. The spectra obtained by 13C NMR and FTIR assigned by comparing the chemical shifts of various signals with shifts of signals from autherized ones reported. The optimal growth temperature and pH of white-rot fungi in medium were $28^{\circ}C$ and 4.5-5.0, respectively. Especially, in temperature and pH range, and mycelial growth, the best white-rot fungus selected was Phanerochaete chrysosporium for biodegradation. For the degradation pathways, the ligninolytic fungus jcultivated with stationary culture using medium of 1% kraft lignin as a substrate for 3 weeks at $28^{\circ}C$. The weight loss of pitch pine kraft lignin was 15.8%. The degraded products extracted successively methoanol, 90% dioxane and diethyl ether. The ether solubles were analyzed by HPLC. Kraft lignin degradation was initiated in $\beta$-O-4 bonds of lignin by the laccase from Phanerochaete chrysosporium and the degraded compounds were produced from the cleavage of $C\alpha$-$C\beta$ linkages at the side chains by oxidation process. After $C\alpha$-$C\beta$ cleavage, $C\alpha$-Carbon was oxidized and changed into aldehyde and acidic compounds such as syringic acid, syringic aldehyde and vanilline. And the other compound as quinonemethide, coumarin, was analyzed. The structural characteristics of kraft lignin were composed of guaiacyl group substituted functional OHs, methoxyl, and carbonyl at C-3, -4, and -5 and these groups were combinated with $\alpha$ aryl ether, $\beta$ aryl ether and biphenyl. Kraft lignin degradation pathways by Phanerochaete chrysosporium were initially accomplished cleavage of $C\alpha$-$C\beta$ linkages and $C\alpha$ oxidation at the propyl side chains and finally cleavage of aromatic ring and oxidation of OHs.

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Combustion Properties of Wood Treated by Combining Phosphorus-Nitrogen Compounds (인-질소 화합물 조합에 의해 처리된 목재의 연소성)

  • Jin, Eui;Chung, Yeong-Jin;Kim, Si-Kuk
    • Applied Chemistry for Engineering
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    • v.27 no.1
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    • pp.39-44
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    • 2016
  • This study was to investigate the characteristics of combustion toxic gases of pinus rigida specimens treated with chemical additives such as pyrophosphoric acid (PP)/ammonuium ion ($NH_4{^+}$), methylenepiperazinomethyl-bis-phosphonic acid (PIPEABP) and $PIPEABP/NH_4{^+}$. Each pinus rigida plates was painted in three times with 15 wt% of each chemical additives in the aqueous solution. After drying these specimens at room temperature, the production of combustion gases and smoke was examined by the cone calorimeter (ISO 5660-1). As a result, the peak mass loss rate time (PMLR time) treated with chemicals was delayed upto 10.5~47.4% compared to that of using untreated specimen. In addition, the peak production of carbon monoxide ($CO\;_{peak}$) of 32.1~71.4% and total smoke release rate (TSRR) of 15.6~43.6% for test pieces treated with the chemical additive were higher than that of using the virgin plate. In particular, for the specimens treated with the chemical additive, the rate of smoke release (RSR) 29.4~41.5% was obtained higher than that of untreated plate except the specimen treated with $PP/4NH_4{^+}$. It can thus be concluded that the treatment using the chemical additive could partially increase the combustion-retardation properties of the species when compared to those of the virgin plate.

Combustive Characteristics of Wood Specimens Treated with Alkylenediaminoalkyl-Bis-Phosphonic Acids (알킬렌디아미노알킬-비스-포스폰산으로 처리된 목재의 연소특성)

  • Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.27 no.6
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    • pp.57-63
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    • 2013
  • This study was performed to test the combustive properties of Pinus rigida specimens treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylene-diaminomethyl-bis-phosphonic acid (MDEDAP). Pinus rigida Plates were painted in three times with 15 wt% alkylenedi-aminoalkyl-bis-phosphonic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with chemicals showed the later time to peak mass loss rate ($TMLR_{peak}$) = (315~420) s than that of virgin plate by reduc-ing the burning rate except for $TPMR_{peak}$ (280 s) treated with DMDAP. In adition, the specimens treated with chemicals showed both the higher total smoke release rate (TSRR) (407.3~902.0) $m^2/m^2$ and $CO_{mean}$ production (407.3~902.0) $m^2/m^2$ than those of virgin plate. Especially, for the specimens treated with PIPEABP, 1st-smoke production rate (1st-SPR) (0.1250~0.1297) g/s was lower than that of virgin plate, while the 2nd-SPR (0.183 g/s) was higher. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated alkylenediaminoalkyl-bis-phos-phonic acids in the virgin Pinus rigida.

Analysis and Conservation of Wooden Objects from Buyeo Era of the Baekje Period (부여 백제시대 목제품의 재질분석과 보존)

  • Kim, Soochul;Oh, Jungae;Namkung, Seung;Lee, Kwanghee
    • Conservation Science in Museum
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    • v.10
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    • pp.43-61
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    • 2009
  • The Buyeo National Museum was requested conservation treatment for wooden objects excavated from three Baekje archeological sites: Neungsan-ri, Ssangbuk-ri, and Gungnamji Pond. Prior to conservation treatment, analysis was conducted to identify the species used. The results of the analysis revealed wood from diverse species of trees including Hard pine, Cryptomeria japonica D. Don, Zelkova serrata Makino, Quercus spp., Platycarya strobilaceae S. et Z., Castanea spp., Torreya nucifera S. et Z., Taxus cuspidata S. et Z., and Salix spp. A high percentage of the objects were made of Cryptomeria japonica D. Don., a species native to Japan, which indicates that exchange with Japan was active at that time. Among the wooden objects, we analyzed lacquer fragments from six pieces of lacquerware, and the characteristics of the lacquer fragments were peculiar to specific artifacts. Most of the fragments were thicker than 100 ㎛. Pure lacquer and mixed black pigment were used. Infrared spectroscopy of the lacquered wooden fragments revealed that they had a very similar absorption band as refined lacquer, confirming that they were painted with lacquer. For their conservation, we immersed the objects in a high molecular weight aqueous solution of PEG#3,350 (10% → 50%) to strengthen them before vacuum freeze-drying.

Conservation Treatment of Mituri (hemp shoes) of the Choseon Dynasty in Sacheon, South Korea (사천 구암 출토 미투리 보존처리)

  • Song, Ji-ae;Jeong, Ah-ruem
    • 보존과학연구
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    • s.34
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    • pp.50-61
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    • 2013
  • The Grave encapsulated by lime soil mixture were excavated with clothing and hemp shoes from the Choseon Dynasty in Gooam, Sacheon. Hemp shoes have wood in the center and their surroundings were made of complex materials including herbaceous ones but the front part was lost or became very fragile. We analyzed the hemp shoes and pre-test of consolidant for conservation treatment of hemp shoes. As a result of analyzing, three kinds of plants were identified. For hemp shoes, Oryza spp, hemp, and one kind of dicotyledones were used and it was analyzed that fabrics attached to the back of Dogaengi was cotton. Conservation methods for pre-test of consolidant, Polyethylene Glycol, Paraloid-B72, Dammar gum, Methyl Cellulose and Silicone resin was selected. The solution was sprayed twice in a 24-hour duration. Properties of consolidant was measured; color difference, glossiness difference, folding streangth and tensile streangth. By comparing the results, PEG was confirmed to the most suitable as consolidant. For the conservation treatment, cleaning and strengthening was conducted. For strengthening treatment, PEG 4000 was selected given that the shoes were made of complex materials. The PEG impregnation method was applied with the PEG 4000 concentration gradually changing from 5% to 80% for reinforcement. Then humidity- controlled drying in order to avoid any rapid environment change.

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Superhydrophilicity of Titania Hybrid Coating Film Imposed by UV Irradiation without Heat-treatment (저온 경화형 초친수성 티타니아 하이브리드 졸의 제조와 친수성 특성 평가에 관한 연구)

  • Kim, Won-Soo;Park, Won-Kyu
    • Journal of Technologic Dentistry
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    • v.29 no.1
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    • pp.121-131
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    • 2007
  • A preparation process's conditions of aqueous sol which contains anatase-type nano titania particles with photocatalyic properties was established by using Yoldas process, so called, DCS(Destabilization of Colloidal Solution) process in this study. And crystal size change and phase transformation of titania particles in aqueous titania sol depending on reaction conditions was investigated by a light scattering method and XRD analysis of frozen dried powders, respectively. This sol with photo catalytic nano titania particles was used to the following hydrophilic hybrid coating film's fabrication and its properties was evaluated. Subsequently, for coating film using the above mentioned aqueous titania sol, non-aqueous titania sol was prepared without any chemical additives and its time stability according to aging time was investigate. By using the above mentioned aqueous titania sol and non-aqueous sol, a complex oxide coating sol for metal and ceramic substrate and a organic-inorganic hybrid coating sol for polymer substrate was prepared and it's hydrophilicity depending on UV irradiation conditions was evaluated. As a conclusions, the following results were obtained. (1)Aqueous titania sol The average particle size of titania in formed aqueous titania sol was distributed between 20$\sim$90nm range depending on reaction conditions. And the crystal phase of titania powders obtained by frozen drying method was changed from amorphous state to anatase and subsequently transformed to rutile crystal phase and it is attributed to concentration gradient in aqueous sol. (2)Non-aqueous titania sol Non-aqueous titania sol was prepared using methanol as a solvent and a little distilled water for hydrolysis and nitric acid as a catalyst were used. The obtained non-aqueous titania sol was stable at room temperature for 20 days. Additionally, non-aqueous titania sol with addition of chealating reagent such as acethylaceton and ethylene glycol prolonged the stability of sol by six months. (3)Complex sol and hybrid sol with super hydrophilicity The above mentioned aqueous titania sol as a main photocataylic component and non-aqueous titania sol as a binder for coating process was used to prepare a complex sol used for metal, ceramic and wood material substrate and also to prepare the organic-inorganic hybrid sol for polymer substrate such as polycarbonate and polyethylene, in which process APMS(3-Aminopropyltrimethoxysilane), GPTS(3-Glycidoxypropyl-trimethoxysilane) as a hydrophilic silane compound and HEMA(2-Hydroxyethyl methacrylate) as a forming network in hybrid coating film were used. The hybrid coating film such as prepared through this process showed a superhydrophilicity below 1$10^{\circ}$ depending on processing conditions and a pencil's hardness over 6 H.

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Combustion Chracteristics of Wood Treated with Bis-(dialkylaminoalkyl) Phosphinic Acids (비스-디알킬아미노알킬 포스핀산으로 처리된 목재의 연소특성)

  • Jin, Eui;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.27 no.4
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    • pp.21-26
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    • 2013
  • This study was performed to test the combustive properties of Pinus rigida plates treated with bis-(dimethylaminomethyl) phosphinic acid (DMDAP), bis-(diethylaminomethyl) phosphinic acid (DEDAP), and bis-(dibuthylaminomethyl) phosphinic acid (DBDAP). Pinus rigida specimens were painted in three times with 15 wt% bis-(dialkylaminoalkyl) phosphinic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It is supposed that the combustion-retardation properties were improved by the partial due to the treated bis-(dialkylaminoalkyl) phosphinic acids in the virgin Pinus rigida. Especially, the specimens treated with chemicals showed both the lower total smoke release rate (TSRR) ($16.94{\sim}18.92m^2/m^2$) and lower $CO_{2mean}$ production (1.98~2.09 kg/kg) than those of virgin plate. However the specimens treated with chemicals showed both the higher peak mass loss rate (PMLR) (0.1250~0.1297 g/s) and higher 1st-smoke production rate (SPR) (0.0153~0.0167 g/s) than those of virgin plate. Compared with virgin Pinus rigida plate, the specimens treated with the bis-dialkylamimoalkyl phosphinic acids showed partially low combustive properties.

Properties and Glue Shear Strength of the Water Soluble Urea-Phenol Copolymer Adhesive as a High Temperature Curing Binder for Plywood (합판용(合板用) 고온경화형(高温硬化型) 수용성(水溶性) 요소(尿素)·페놀공축합수지(共縮合樹脂)의 성질(性質)과 그 접착강도(接着強度))

  • Lee, Hwa Hyoung
    • Journal of Korean Society of Forest Science
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    • v.60 no.1
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    • pp.51-57
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    • 1983
  • Properties and glue shear strength of each water soluble rues-phenol copolymer adhesive and phenolic resin adhesive were examined as a high temperature curing binder through the manufacture of plywood made of Kapur veneer. The former has different molar ratio and the latter was made from different catalyst method. The results are summarized as follows: 1) Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.67 to 0.82 and their moisture contents met the K.S. standard 2) In dry and wet shear strength, adhesives with 60 percent of non volatile content showed higher values than those with 50 percent except phenolic resin. Urea-phenol copolymer resin with 20 percent of phenol content exhibited the highest, and that with 70 percent the lowest. Filling effect of wood flour on the bonding strength is great in urea-phenol copolymer resin with more than 50 percent of phenol content, especially significant in 50 percent of non volatile content including alkali catalyst phenolic resin. Alkali and acid catalyst methods were the highest among the adhesive manufacture methods. In wet strength, urea resin belongs to the lowest group. 3) In glue shear strength after boiling and drying test, no method for manufacturing phenolic formaldehyde resin adhesive was stronger than alkali and acid catalyst methods. Phenolic resin made from alkali catalyst method needs a wood flour filler to improve the bonding quality. Urea-phenol copolymer resin with 10 percent of phenol content showed the reasonable water resistance.

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