Moisture Content Prediction Below and Above Fiber Saturation Point by Partial Least Squares Regression Analysis on Near Infrared Absorption Spectra of Korean Pine

This study was performed to predict the surface moisture content of Korean pine (Pinus koraiensis) with low moisture content (approximately 0%) and high moisture content above the FSP using near IR spectroscopy. Near IR absorbance spectra of circular specimens were acquired at various moisture contents at 25°C. To enhance the precision of the regression model, mathematical preprocessing was performed by determining the three-point moving average and Norris second derivatives. After preprocessing, partial least squares regression was carried out to establish the surface moisture content prediction model. We divided the specimens into two groups based on their moisture contents. For the first group, which possessed moisture contents less than 30%, the R2 values and root mean squared error of prediction (RMSEP) of the model were 0.96 and 1.48, respectively. For the second group, which possessed moisture contents greater than 30%, the R2 values and RMSEP of the model were 0.94 and 4.88, respectively. For all moisture contents, the R2 and RMSEP were 0.96 and 5.15, respectively. As the range of moisture contents included in the prediction model was expanded, the error of the model increased. In addition, the peak positions of the water absorption band (1440 and 1930 nm) shifted to longer wavelengths at higher moisture contents

Wood Properties and Drying Characteristics of Korean Sawtooth Oak (Quercus acutissima Carruth.) Wood: Poster presentation

The objective of this study was to present the wood properties and drying characteristics of sawtooth oak (Quercus acutissima Carruth.) for the spread of its utilization in South Korea. The annual ring, latewood ratio, dimension of vessels, density, and shrinkage of specimens manufactured from five sawtooth oak trees were measured and compared by age class. And drying rate and drying defects of sawtooth oak boards were measured during kiln-drying. In order to present the processing performance of surface on sawtooth oak wood, the roughness on radial and tangential sections after sawing and planing process was measured by roughness tester and the texture of surface on each section was observed by stereoscopic microscope. It is expected that the fundamental properties of Korean sawtooth oak wood presented in this study will contribute to the extension of utilization of Korean oak species

Determination of Internal Moisture Transport and Surface Emission Coefficients for Eastern White Pine

Moisture movement in eastern white pine wood specimens was evaluated during drying at specific temperature and RH conditions. The objective of this work was to build an appropriate numeric analysis model for predicting moisture profile changes in wood and apply this to the kiln-drying of large cross-section eastern white pine timbers. The internal moisture transport coefficients were dependent on the temperature and average moisture content, and the surface emission coefficients on the water vapor pressure in air adjacent to the surface. The internal moisture transport coefficients decreased with decreasing temperature and internal moisture content. Surface emission coefficients increased with increasing temperature and decreasing surface moisture content

Effect of Using Laser Incising Treatment and Fire-Retardant Coating on Larix kaempferi Wood to Improve Fire Retardant Performance

To improve fire-retardant performance of Japanese larch (Larix kaempferi) wood, this study analyzed the effect of pinholes made by laser incising and fire retardant (FR) coating on the surface of Japanese larch wood. Combustion properties such as peak heat release rate (PHRR) and total heat release (THR) of Japanese larch and Korean red pine (Pinus densiflora) wood without FRs showed similar tendencies. The comparison of the combustion properties on wood injected with an inorganic water-soluble FR under vacuum revealed that the PHRR and the THR of Korean red pine wood decreased by 37 and 62%, respectively. FR was injected into the Japanese larch specimens with pinholes on the surface and additionally coated with 5% sodium silicate and 35% potassium bromide. The results indicated a 16 to 25 and 19% reduction in PHRR and THR, respectively, compared to those without the FR. Despite the pinholes and FR coating, the FR employed in this study did not meet the standards set in Korea (THR of 8 MJ/m2). This study serves as a reference for future studies on the application of pressurized conditions and other surface treatments to improve the FR percent injection and performance of Japanese larch wood

DETERMINATION OF INTERNAL MOISTURE TRANSPORT AND SURFACE EMISSION COEFFICIENTS FOR EASTERN WHITE PINE

Moisture movement in eastern white pine wood specimens was evaluated during drying at specific temperature and RH conditions. The objective of this work was to build an appropriate numeric analysis model for predicting moisture profile changes in wood and apply this to the kiln-drying of large cross-section eastern white pine timbers. The internal moisture transport coefficients were dependent on the temperature and average moisture content, and the surface emission coefficients on the water vapor pressure in air adjacent to the surface. The internal moisture transport coefficients decreased with decreasing temperature and internal moisture content. Surface emission coefficients increased with increasing temperature and decreasing surface moisture content.OAIID:oai:osos.snu.ac.kr:snu2008-01/102/0000039153/4SEQ:4PERF_CD:SNU2008-01EVAL_ITEM_CD:102USER_ID:0000039153ADJUST_YN:YEMP_ID:A076734DEPT_CD:524CITE_RATE:.702FILENAME:2008 40(4) D and SEC (White Pine).pdfDEPT_NM:산림과학부EMAIL:[email protected]:

Crystal Structure of the N-terminal Domain of Anaphase-promoting Complex Subunit 7

Anaphase-promoting complex or cyclosome (APC/C) is an unusual E3 ubiquitin ligase and an essential protein that controls mitotic progression. APC/C includes at least 13 subunits, but no structure has been determined for any tetratricopeptide repeat (TPR)-containing subunit (Apc3 and -6-8) in the TPR subcomplex of APC/C. Apc7 is a TPR-containing subunit that exists only in vertebrate APC/C. Here we report the crystal structure of quad mutant of nApc7 (N-terminal fragment, residues 1-147) of human Apc7 at a resolution of 2.5 angstrom. The structure of nApc7 adopts a TPR-like motif and has a unique dimerization interface, although the protein does not contain the conserved TPR sequence. Based on the structure of nApc7, in addition to previous experimental findings, we proposed a putative homodimeric structure for full-length Apc7. This model suggests that TPR-containing subunits self-associate and bind to adaptors and substrates via an IR peptide in TPR-containing subunits of APC/C.This work was supported by the 21C Frontier Functional Proteomics Project of the Korean Ministry of Science and Technology Grant FPR 08-A2-110 and by the Innovative Research Institute for Cell Therapy, Republic of Korea, Grant A062260.Holm L, 2008, BIOINFORMATICS, V24, P2780, DOI 10.1093/bioinformatics/btn507Han D, 2008, PROTEINS, V70, P900, DOI 10.1002/prot.21597Ohi MD, 2007, MOL CELL, V28, P871, DOI 10.1016/j.molcel.2007.10.003Nyarko A, 2007, BIOCHEMISTRY-US, V46, P11331, DOI 10.1021/bi700735tKrissinel E, 2007, J MOL BIOL, V372, P774, DOI 10.1016/j.jmb.2007.05.022Pal M, 2007, J CELL SCI, V120, P3238, DOI 10.1242/jcs.004762Thornton BR, 2006, GENE DEV, V20, P3069, DOI 10.1101/gad.1478306Peters JM, 2006, NAT REV MOL CELL BIO, V7, P644, DOI 10.1038/nrm1988Wu YK, 2006, NAT STRUCT MOL BIOL, V13, P589, DOI 10.1038/nsmb1106Hayes MJ, 2006, NAT CELL BIOL, V8, P607, DOI 10.1038/ncb1410Painter J, 2006, ACTA CRYSTALLOGR D, V62, P439, DOI 10.1107/S0907444906005270Thornton BR, 2006, GENE DEV, V20, P449, DOI 10.1101/gad.1396906Eytan E, 2006, P NATL ACAD SCI USA, V103, P2081, DOI 10.1073/pnas.0510695103Tanaka T, 2006, BIOPOLYMERS, V84, P161, DOI 10.1002/hip.20361Passmore LA, 2005, MOL CELL, V20, P855, DOI 10.1016/j.molcel.2005.11.003Dube P, 2005, MOL CELL, V20, P867, DOI 10.1016/j.molcel.2005.11.008Turnell AS, 2005, NATURE, V438, P690, DOI 10.1038/nature04151Kraft C, 2005, MOL CELL, V18, P543, DOI 10.1016/j.molcel.2005.04.023Wilson CGM, 2005, FEBS J, V272, P166, DOI 10.1111/j.1432-1033.2004.04397.xPark KH, 2005, BREAST CANCER RES, V7, pR238, DOI 10.1186/bcr978Emsley P, 2004, ACTA CRYSTALLOGR D, V60, P2126, DOI 10.1107/S0907444904019158Krissinel E, 2004, ACTA CRYSTALLOGR D, V60, P2256, DOI 10.1107/S0907444904026460van Roessel P, 2004, CELL, V119, P707, DOI 10.1016/j.cell.2004.11.028Jinek M, 2004, NAT STRUCT MOL BIOL, V11, P1001, DOI 10.1038/nsmb833Passmore LA, 2004, BIOCHEM J, V379, P513, DOI 10.1042/BJ20040198Konishi Y, 2004, SCIENCE, V303, P1026, DOI 10.1126/science.1093712Terwilliger T, 2004, J SYNCHROTRON RADIAT, V11, P49, DOI 10.1107/S0909049503023938Kraft C, 2003, EMBO J, V22, P6598, DOI 10.1093/emboj/cdg627Gonzalez A, 2003, ACTA CRYSTALLOGR D, V59, P1935, DOI 10.1107/S0907444903017700Vodermaier HC, 2003, CURR BIOL, V13, P1459, DOI 10.1016/S0960-9822(03)00581-5Main ERG, 2003, STRUCTURE, V11, P497, DOI 10.1016/S0969-2126(03)00076-5Terwilliger TC, 2003, METHOD ENZYMOL, V374, P22, DOI 10.1016/S0076-6879(03)74002-6Yoon HJ, 2002, CURR BIOL, V12, P2048, DOI 10.1016/S0960-9822(02)01331-3Winn MD, 2002, ACTA CRYSTALLOGR D, V58, P1929, DOI 10.1107/S0907444902016116Harper JW, 2002, GENE DEV, V16, P2179, DOI 10.1101/gad.1013102Peters JM, 2002, MOL CELL, V9, P931, DOI 10.1016/S1097-2765(02)00540-3Gieffers C, 2001, MOL CELL, V7, P907, DOI 10.1016/S1097-2765(01)00234-9Winn MD, 2001, ACTA CRYSTALLOGR D, V57, P122, DOI 10.1107/S0907444900014736Pfleger CM, 2000, GENE DEV, V14, P655Visintin R, 1997, SCIENCE, V278, P460, DOI 10.1126/science.278.5337.460Garnier J, 1996, METHOD ENZYMOL, V266, P540THOMPSON JD, 1994, NUCLEIC ACIDS RES, V22, P4673, DOI 10.1093/nar/22.22.4673LAMB JR, 1994, EMBO J, V13, P4321JONES TA, 1991, ACTA CRYSTALLOGR A, V47, P110, DOI 10.1107/S0108767390010224GLOTZER M, 1991, NATURE, V349, P132, DOI 10.1038/349132a0MATTHEWS BW, 1968, J MOL BIOL, V33, P491, DOI 10.1016/0022-2836(68)90205-2

Near-Infrared Spectroscopic Analysis for Classification of Water Molecules in Wood by a Theory of Water Mixtures

This study was conducted to analyze the mechanism of moisture adsorption-desorption in wood using near-IR (NIR) spectroscopy. NIR spectra reflected from moist wood were acquired, and spectra in the range from 1800-2100 nm, which were sensitive to water variation, were decomposed into three different components according to the Buijs and Choppin theory. It is assumed that the three components represent three types of bound water: water molecules without -OH groups engaged in hydrogen bonds (S0), water molecules with one -OH group engaged in a hydrogen bond (S1), and water molecules with two -OH groups engaged in hydrogen bonds (S2). Ratios of the decomposed spectra of NIR absorbed by each type of water molecule were analyzed during changes in water adsorption-desorption states. Through this analysis, a sorption model for predicting the structural state of each water component in wood was constructed. This model may be used to explain the effect of each water component on the occurrence of hysteresis as well as the transient state between bound water and free water. Based on the model, it was concluded that the monomolecular water layer in yellow poplar wood formed below approximately 8% MC during adsorption. Additionally, the phenomenon of hysteresis was demonstrated by the difference between the ratios of the S2 components in desorption and adsorption

Evaluation of Drying and Anatomical Characteristic of Mongolian Oak Lumber by Kiln Drying due to storage time after sawing: Poster presentation

Based on the 2017 statistics of the Korea Forest Service, the amount of annual production of domestic roundwood was 4.5 million ㎥. Twenty eight percent of the production was hardwood roundwood. About 80% of the hardwood was Quercus species. The hardwood roundwoods were mainly used for wood chips (50%) and medium density fiberboard (MDF)(26%). Only 6% of the hardwood roundwoods were used for sawn timber. Most of oak forests in Korea were not managed well. Therefore, diameter of oak trees was relatively small with lots of flaws, such as inside decay, discoloration etc., since many of them were reproduced by sprout forest. Oak trees produced from unmanaged forests are prone to drying defects. To overcome this proneness, drying and anatomical characteristic of Mongolian Oak (Quercus mongolica) lumber (thickness 30 ㎜ x width 100 ㎜ x length 1,900 ㎜) were investigated in this study. Shrinkage and color difference (E) due to kiln dry was measured. In order to evaluate drying defects, the degree of surface check was investigated. Warp of lumber, such as cup, bow, crook, and twist, were also measured after drying process. Tylosis formation between one month and six months after sawing was observed microscopically. In order to develop value-added products from domestic oaks, the yield rate from standing tree to the flooring board were calculated. It is expected that efficient production plan for the value added products from domestic oak species would be proposed based on the results of this study, which are not being used as commercial sawn timber in Korea currently

Determining surface emission coefficient of wood using theoretical methods and near-infrared spectroscopy

Emission of surface water on wood should be controlled because moisture movement on the wood surface initiates changes in its morphological, physical, chemical, and biological properties. In this study, surface moisture content (SMC) of yellow poplar (Liriodendron tulipifera L.) wood was measured by a near-infrared spectroscopy (NIRS) technique, nondestructively and continuously, during unsteadystate desorption conditions. With these SMC data, surface emission coefficients (SECs) were determined continuously while the wood was being dried. These experimentally determined coefficients were compared with values that were converted from the theoretically determined mass transfer coefficients. The conversion method, which was developed to facilitate a comparison among the mass transfer coefficients, indicated that the boundary layer theory was useful in evaluating the degree of external moisture resistance while the wood dried. Also, the NIRS technique can be used for determining SEC at each specific point of wood, experimentally, in real time.OAIID:oai:osos.snu.ac.kr:snu2013-01/102/0000039153/1SEQ:1PERF_CD:SNU2013-01EVAL_ITEM_CD:102USER_ID:0000039153ADJUST_YN:NEMP_ID:A076734DEPT_CD:524CITE_RATE:.722FILENAME:WFS 45(1) 76-83.pdfDEPT_NM:산림과학부EMAIL:[email protected]_YN:YCONFIRM:

Determining Surface Emission Coefficient of Wood Using Theoretical Methods and Near-Infrared Spectroscopy

Emission of surface water on wood should be controlled because moisture movement on the wood surface initiates changes in its morphological, physical, chemical, and biological properties. In this study, surface moisture content (SMC) of yellow poplar (Liriodendron tulipifera L.) wood was measured by a near-infrared spectroscopy (NIRS) technique, nondestructively and continuously, during unsteady-state desorption conditions. With these SMC data, surface emission coefficients (SECs) were determined continuously while the wood was being dried. These experimentally determined coefficients were compared with values that were converted from the theoretically determined mass transfer coefficients. The conversion method, which was developed to facilitate a comparison among the mass transfer coefficients, indicated that the boundary layer theory was useful in evaluating the degree of external moisture resistance while the wood dried. Also, the NIRS technique can be used for determining SEC at each specific point of wood, experimentally, in real time