The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Bernard Riedl - One of the best experts on this subject based on the ideXlab platform.
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effects of Fire Retardant Treatment and wood grain on three dimensional changes of sandwich panels made from bubinga decorative veneer
Wood Material Science and Engineering, 2020Co-Authors: Jedi Roseroalvarado, Roger E Hernandez, Bernard RiedlAbstract:The effects of a Fire-Retardant Treatment (FRT) and wood grain on three-dimensional changes of aircraft sandwich panels were evaluated. Unvarnished and varnished panels having the outer decorative ...
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Surface deformation of walnut burl veneer on aircraft sandwich panels assessed by three-dimensional digital image correlation
Wood Science and Technology, 2018Co-Authors: Jedi Rosero-alvarado, Roger E Hernandez, Bernard RiedlAbstract:The three-dimensional digital image correlation method (3D-DIC) was used to study the surface deformation of aircraft interior sandwich panels as a result of a water vapor adsorption Treatment. The effects of a Fire-Retardant Treatment and wood burl structure were evaluated. Unvarnished and varnished panels made with walnut burl veneer ( Juglans hibdsii L.) were selected and analyzed separately. Half of the samples from each type of panel received a Fire-Retardant Treatment (phosphate based) on all three layers of the decorative plywood. The other half had the two inner layers treated and the outer layer untreated. Swirl grain and bud traces areas were identified on the burl pattern of veneer surfaces. Samples preconditioned to 20 °C and 40% relative humidity underwent an adsorption (25 °C, 90% RH) Treatment. Changes in moisture content were measured after adsorption. Full-field swelling strains (in-plane) and Z-displacements (out-of-plane) were obtained from each figure type in samples after the adsorption conditioning. The application of the 3D-DIC method revealed that the Fire-Retardant Treatment increased the swelling strains and Z-displacements on unvarnished and varnished surface panels. This Treatment also caused a significant differentiation of Z-displacements on swirl zones compared to bud trace zones in varnished panels. Thus, the degree of surface deformation depended on the burl wood structure and the Fire-Retardant Treatment. The 3D-DIC method was suitable for evaluating local swelling strains and Z-displacements on unvarnished and varnished wood veneer surfaces.
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effects of Fire Retardant Treatment and burl wood structure on three dimensional changes of sandwich panels made from walnut decorative veneer
Bioresources, 2017Co-Authors: Jedi Roseroalvarado, Roger E Hernandez, Bernard RiedlAbstract:The effects of a Fire-Retardant Treatment and burl wood structure on the three-dimensional changes of aircraft sandwich panels were evaluated. Unvarnished and varnished panels with an outer decorative layer made from walnut burl (Juglans hindsii L.) were studied. Half of the samples from each type of panel received a Fire-Retardant Treatment (phosphate-based) on all three layers of the decorative plywood. The other half had the two inner layers treated and the outer layer was left untreated. Three different wood areas formed by rotary peeling and by the grain orientation from the burl structure were identified and their veneer surfaces were separately studied. Samples pre-conditioned at 20 °C and 40% relative humidity (RH) underwent adsorption (25 °C, 90% RH) and then desorption (25 °C, 40% RH) Treatments. Changes in the moisture content (MC), swelling, shrinkage, roughness, and waviness were measured after each moisture exposure condition. The results showed that the Fire-Retardant Treatment significantly increased the MC, swelling, shrinkage, roughness, and waviness of the unvarnished and varnished panels. This Treatment also affected the roughness and waviness of the burl wood structure for the unvarnished panels. The effect of this anatomical feature was not noticeable in the varnished panels.
Ming-jer Tsai - One of the best experts on this subject based on the ideXlab platform.
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Fire-Retardant-treated low-formaldehyde-emission particleboard made from recycled wood-waste
Bioresource Technology, 2008Co-Authors: Song Yung Wang, Li Ting Lin, Cheng Jung Lin, Te-hsin Yang, Ming-jer TsaiAbstract:The objective of this study was to manufacture Fire-Retardant-treated low-formaldehyde-emission particleboard from recycled wood-waste particles using polymeric 4,4′-methylenediphenyl isocyanate (PMDI) and phenol-formaldehyde (PF) resins. The influence of the PMDI/PF ratio (ratio of particles sprayed with PMDI to particles sprayed with PF, w/w) after Fire Retardant Treatment on formaldehyde emissions, mechanical properties, and surface Fire resistant performance of the manufactured particleboard was investigated. The experimental results showed that the formaldehyde emissions linearly decreased with an increasing PMDI/PF ratio. Moreover, the bending strength, internal bond strength, and screw holding strength increased with an increasing PMDI/PF ratio. The thickness swelling of the particleboard was improved by using an increasing PMDI/PF ratio. Furthermore, the Fire-Retardant-treated low-formaldehyde-emission particleboards fabricated in our study could pass the third grade standard of surface Fire resistant performance as specified by CNS 6532. © 2007 Elsevier Ltd. All rights reserved.
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Fire-Retardant-treated low-formaldehyde-emission particleboard made from recycled wood-waste.
Bioresource Technology, 2007Co-Authors: Song Yung Wang, Te-hsin Yang, Ming-jer TsaiAbstract:Abstract The objective of this study was to manufacture Fire-Retardant-treated low-formaldehyde-emission particleboard from recycled wood-waste particles using polymeric 4,4′-methylenediphenyl isocyanate (PMDI) and phenol-formaldehyde (PF) resins. The influence of the PMDI/PF ratio (ratio of particles sprayed with PMDI to particles sprayed with PF, w/w) after Fire Retardant Treatment on formaldehyde emissions, mechanical properties, and surface Fire resistant performance of the manufactured particleboard was investigated. The experimental results showed that the formaldehyde emissions linearly decreased with an increasing PMDI/PF ratio. Moreover, the bending strength, internal bond strength, and screw holding strength increased with an increasing PMDI/PF ratio. The thickness swelling of the particleboard was improved by using an increasing PMDI/PF ratio. Furthermore, the Fire-Retardant-treated low-formaldehyde-emission particleboards fabricated in our study could pass the third grade standard of surface Fire resistant performance as specified by CNS 6532.
J. E. Winandy - One of the best experts on this subject based on the ideXlab platform.
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Development of a Testing Protocol for Effects on Strength of Laboratory-Manufactured, Fire Retardant-Treated Strandboard
Wood and Fiber Science, 2015Co-Authors: H. M. Barnes, J. E. Winandy, Joseph M. HillAbstract:This research investigated the mechanical properties of laboratory-manufactured, Fire Retardanttreated (FRT) strandboard in an effort to establish laboratory testing protocols for these types of composite products. This study evaluates both the initial effects of Fire Retardant Treatment and the effects of extended high-temperature exposure. Two sets of FRT and untreated strandboard panels were manufactured and tested. Preliminary work had assessed the effect of strandboard specimen width on the stability of mean and variance estimates obtained when testing matched treated and untreated specimens with four different widths. Those results indicated that use of ≥200 mm-wide strandboard specimens decreased both variation and error associated in mean estimates compared with testing narrower-width strandboard specimens. The findings in this study show that the testing protocols developed for laboratorymanufactured, FRT strandboard were both reproducible and adequately severe. These laboratory test methods successfully identified the potential initial strength effects on strandboard performance and their potential for secondary strength loss when exposed for an extended time in a high temperature environment minimizing the costs of using large commercial production facilities.
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Effect of Fire-Retardant Treatment on plywood pH and the relationship of pH to strength properties
Wood Science and Technology, 1999Co-Authors: S. T. Lebow, J. E. WinandyAbstract:This paper investigates the relationship between wood pH and the strength properties of Fire-Retardant-treated (FRT) plywood, as it is affected by Fire-Retardant (FR) formulations, processing variables, and extended high temperature exposure conditions. The objectives of this study were to (1) identify the effect of post-Treatment kiln-drying temperature, followed by high temperature exposure, on wood pH; (2) identify the effect of various mixtures of FR components, followed by high temperature exposure, on wood pH; (3) determine if Treatment effects on strength and pH are affected by plywood thickness; and (4) quantify the relationship between changes in wood pH and strength loss and whether pH can be used as a predictor of strength loss. Results indicate that the differences in pH resulting from the initial redry temperature became insignificant after extended periods of high temperature exposure. All FR Treatments studied caused large, rapid decreases in pH, with the most rapid decreases occurring with formulations containing phosphoric acid. Additions of borate compounds, especially disodium octaborate tetrahydrate (Timbor), produced a measurable buffering effect that slowed or lessened the decreases in pH. No differences in the effect of FRT on the wood pH-strength relationship were noted between the two plywood thicknesses evaluated. A strong relationship was noted between changes in pH of the plywood and reductions in strength and energy-related properties. These findings suggest that the pH of FRT plywood is a good indicator of its current condition and may have potential as a predictor of future strength loss as the plywood is subjected to elevated in-service temperatures.
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The role of grade and thickness in the degradation of Fire-Retardant-treated plywood
Forest Products Journal, 1998Co-Authors: S. T. Lebow, J. E. WinandyAbstract:In some cases, Fire-Retardant-treated plywood used since 1980 for roof sheathing has rapidly degraded and failed, apparently because of thermally induced acid hydrolysis. This study sought to determine whether plywood grade or thickness influences the manner in which Fire-Retardant Treatment (FRT) and subsequent high-temperature exposure affects the strength properties of plywood. The effects of FRT were evaluated on two thicknesses and three commercial grades of southern pine plywood as well as plywood constructed from nearly defect-free N-grade veneer. Specimens were treated with monoammonium phosphate (MAP), then subjected to exposure at 66°C (150°F) and 75 percent relative humidity for either 30,60. or 90 days. Modulus ofrupture (MOR), work to maximum load (WML), (MOE) ofthe specimens were evaluated. Results suggest that the rate ofplywood degrade resulting from FRT, redrying, and subsequent high-temperature exposure is largely independent of plywood quality or grade. Although the initial strength loss caused by FRT and redrying appeared greater for the thinner plywood, degrade during subsequent temperature exposure appeared to be independent of plywood thickness. Thus, it appears that findings from previous studies on thermal degrade using high quality, N-grade plywood are readily applicable to commercial grades and thicknesses. Evaluation of the effects of knots and voids on MOR revealed that these defects are only partially responsible for the difference in bending strength among specimens.
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effects of Fire Retardant retention borate buffers and redrying temperature after Treatment on thermal induced degradation
Forest Products Journal, 1997Co-Authors: J. E. WinandyAbstract:All wood products are prone to strength loss from extended exposure to temperatures above 65°C (150°F). The higher the temperature, the less time required to produce a given reduction in strength. In the United States, problems with Fire-Retardant-treated plywood roof sheathing and roof-truss lumber have occurred in the field; thermal degradation has occurred in as few as 2 to 5 years after installation. Before the thermal-induced degradation of treated wood can be fully modeled, we must more completely determine the relationships of Treatment processing factors, mixtures of chemical components, post-Treatment (redrying) temperature, and in-service moisture to performance, and relate the results to in-service temperature-induced strength degradation. In the study reported here, variation in redrying temperature from 49°C (120°F) to 88°C (190°F) had little effect on the magnitude or rate of subsequent thermal degradation when the treated plywood was exposed at 65°C (150°F) for up to 290 days. The addition of borate-based buffers to Fire-Retardant-Treatment chemicals was found to significantly mitigate thermal degradation. Finally, the results imply that the combined effects of phosphate retention and accumulated thermal exposure (from both redrying and in-service high temperatures) are additive and cumulative.
Roger E Hernandez - One of the best experts on this subject based on the ideXlab platform.
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effects of Fire Retardant Treatment and wood grain on three dimensional changes of sandwich panels made from bubinga decorative veneer
Wood Material Science and Engineering, 2020Co-Authors: Jedi Roseroalvarado, Roger E Hernandez, Bernard RiedlAbstract:The effects of a Fire-Retardant Treatment (FRT) and wood grain on three-dimensional changes of aircraft sandwich panels were evaluated. Unvarnished and varnished panels having the outer decorative ...
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Surface deformation of walnut burl veneer on aircraft sandwich panels assessed by three-dimensional digital image correlation
Wood Science and Technology, 2018Co-Authors: Jedi Rosero-alvarado, Roger E Hernandez, Bernard RiedlAbstract:The three-dimensional digital image correlation method (3D-DIC) was used to study the surface deformation of aircraft interior sandwich panels as a result of a water vapor adsorption Treatment. The effects of a Fire-Retardant Treatment and wood burl structure were evaluated. Unvarnished and varnished panels made with walnut burl veneer ( Juglans hibdsii L.) were selected and analyzed separately. Half of the samples from each type of panel received a Fire-Retardant Treatment (phosphate based) on all three layers of the decorative plywood. The other half had the two inner layers treated and the outer layer untreated. Swirl grain and bud traces areas were identified on the burl pattern of veneer surfaces. Samples preconditioned to 20 °C and 40% relative humidity underwent an adsorption (25 °C, 90% RH) Treatment. Changes in moisture content were measured after adsorption. Full-field swelling strains (in-plane) and Z-displacements (out-of-plane) were obtained from each figure type in samples after the adsorption conditioning. The application of the 3D-DIC method revealed that the Fire-Retardant Treatment increased the swelling strains and Z-displacements on unvarnished and varnished surface panels. This Treatment also caused a significant differentiation of Z-displacements on swirl zones compared to bud trace zones in varnished panels. Thus, the degree of surface deformation depended on the burl wood structure and the Fire-Retardant Treatment. The 3D-DIC method was suitable for evaluating local swelling strains and Z-displacements on unvarnished and varnished wood veneer surfaces.
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effects of Fire Retardant Treatment and burl wood structure on three dimensional changes of sandwich panels made from walnut decorative veneer
Bioresources, 2017Co-Authors: Jedi Roseroalvarado, Roger E Hernandez, Bernard RiedlAbstract:The effects of a Fire-Retardant Treatment and burl wood structure on the three-dimensional changes of aircraft sandwich panels were evaluated. Unvarnished and varnished panels with an outer decorative layer made from walnut burl (Juglans hindsii L.) were studied. Half of the samples from each type of panel received a Fire-Retardant Treatment (phosphate-based) on all three layers of the decorative plywood. The other half had the two inner layers treated and the outer layer was left untreated. Three different wood areas formed by rotary peeling and by the grain orientation from the burl structure were identified and their veneer surfaces were separately studied. Samples pre-conditioned at 20 °C and 40% relative humidity (RH) underwent adsorption (25 °C, 90% RH) and then desorption (25 °C, 40% RH) Treatments. Changes in the moisture content (MC), swelling, shrinkage, roughness, and waviness were measured after each moisture exposure condition. The results showed that the Fire-Retardant Treatment significantly increased the MC, swelling, shrinkage, roughness, and waviness of the unvarnished and varnished panels. This Treatment also affected the roughness and waviness of the burl wood structure for the unvarnished panels. The effect of this anatomical feature was not noticeable in the varnished panels.
Song Yung Wang - One of the best experts on this subject based on the ideXlab platform.
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Fire-Retardant-treated low-formaldehyde-emission particleboard made from recycled wood-waste
Bioresource Technology, 2008Co-Authors: Song Yung Wang, Li Ting Lin, Cheng Jung Lin, Te-hsin Yang, Ming-jer TsaiAbstract:The objective of this study was to manufacture Fire-Retardant-treated low-formaldehyde-emission particleboard from recycled wood-waste particles using polymeric 4,4′-methylenediphenyl isocyanate (PMDI) and phenol-formaldehyde (PF) resins. The influence of the PMDI/PF ratio (ratio of particles sprayed with PMDI to particles sprayed with PF, w/w) after Fire Retardant Treatment on formaldehyde emissions, mechanical properties, and surface Fire resistant performance of the manufactured particleboard was investigated. The experimental results showed that the formaldehyde emissions linearly decreased with an increasing PMDI/PF ratio. Moreover, the bending strength, internal bond strength, and screw holding strength increased with an increasing PMDI/PF ratio. The thickness swelling of the particleboard was improved by using an increasing PMDI/PF ratio. Furthermore, the Fire-Retardant-treated low-formaldehyde-emission particleboards fabricated in our study could pass the third grade standard of surface Fire resistant performance as specified by CNS 6532. © 2007 Elsevier Ltd. All rights reserved.
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Fire-Retardant-treated low-formaldehyde-emission particleboard made from recycled wood-waste.
Bioresource Technology, 2007Co-Authors: Song Yung Wang, Te-hsin Yang, Ming-jer TsaiAbstract:Abstract The objective of this study was to manufacture Fire-Retardant-treated low-formaldehyde-emission particleboard from recycled wood-waste particles using polymeric 4,4′-methylenediphenyl isocyanate (PMDI) and phenol-formaldehyde (PF) resins. The influence of the PMDI/PF ratio (ratio of particles sprayed with PMDI to particles sprayed with PF, w/w) after Fire Retardant Treatment on formaldehyde emissions, mechanical properties, and surface Fire resistant performance of the manufactured particleboard was investigated. The experimental results showed that the formaldehyde emissions linearly decreased with an increasing PMDI/PF ratio. Moreover, the bending strength, internal bond strength, and screw holding strength increased with an increasing PMDI/PF ratio. The thickness swelling of the particleboard was improved by using an increasing PMDI/PF ratio. Furthermore, the Fire-Retardant-treated low-formaldehyde-emission particleboards fabricated in our study could pass the third grade standard of surface Fire resistant performance as specified by CNS 6532.