The Experts below are selected from a list of 22962 Experts worldwide ranked by ideXlab platform
Fred M. Lamb - One of the best experts on this subject based on the ideXlab platform.
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Investigation of Boiling Front During Vacuum Drying of Wood
Wood and Fiber Science, 2007Co-Authors: Zhangjing Chen, Fred M. LambAbstract:The objective of this research was to theoretically and experimentally investigate the boiling phenomenon and the existence of a boiling front inside wood during continuous and cyclic Vacuum Drying. The Vacuum Drying model was theoretically developed based on an energy balance. The experimental results supported the hypothesis that there is a boiling front during Vacuum Drying. From the boiling front to the surface of the wood, the boiling temperature is lower than the wood temperature, so water in this region boils. From the boiling front to the center of wood, there is no boiling because the pressure inside the wood is higher than the saturation vapor pressure. The boiling front retreats from the surface to the center of the wood as Drying proceeds. The speed of retreat depends on the heat supply and properties of the wood, such as permeability and conductivity.
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Analysis of the Vacuum Drying Rate for Red Oak in a Hot Water Vacuum Drying System
Drying Technology, 2007Co-Authors: Zhangjing Chen, Fred M. LambAbstract:Red oak boards of 76.2 cm (long) × 7.62 cm (wide) × 2.54 cm (thick) were dried from green moisture content (MC) to 7% MC in the hot water Vacuum-Drying system. These boards were dried at the pressure of 12 mm Hg and the temperatures ranging from 30 to 50°C within 25 to 70 h. Drying rates were measured and Drying curves were calculated. The results showed that the Drying rate was higher at higher temperatures. The Vacuum Drying was faster when wood MC was above 30% than when it was less than 30%. The individual samples did not dry at the same Drying rates even at the same Drying conditions because of anatomical variations between boards.
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Analysis of cyclic Vacuum Drying curve
Wood Science and Technology, 2003Co-Authors: Zhangjing Chen, Fred M. LambAbstract:The objective of this research was to analyze the cyclic Vacuum Drying curve within one cycle. Red oak specimens of two different groups, square in cross-section, were used. Group one was comprised of four different thicknesses (2.54, 3.81, 5.08, and 6.35 cm) with a length of 25.4 cm and group two was comprised of three different lengths (12.7, 25.4, and 38.1 cm) with the thickness of 2.54 cm. The specimens were heated to 60°C in the heating oven and then dried in the Vacuum oven at 18 mm Hg. The Vacuum oven was at room temperature (20°C). The Vacuum pump was kept running for 140 min. It was found that the cyclic Vacuum Drying curve consisted of two distinct parts. The fast Drying period lasted about 10 to 15 min. The slow Drying period occurred when the pressure inside wood approached the ambient pressure. Most of the moisture was removed during the fast Drying period.
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Vacuum Drying of small wood components at room temperature
Forest Products Journal, 2001Co-Authors: Zhangjing Chen, Fred M. LambAbstract:This study explores continuous Vacuum Drying at room temperature. Small specimens of red oak were dried at 20°C and at a pressure of about 18 mm Hg. The results showed that small wood components can be Vacuum dried at room temperature with little or no degrade at reasonable Drying rates.
Zhangjing Chen - One of the best experts on this subject based on the ideXlab platform.
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Investigation of Boiling Front During Vacuum Drying of Wood
Wood and Fiber Science, 2007Co-Authors: Zhangjing Chen, Fred M. LambAbstract:The objective of this research was to theoretically and experimentally investigate the boiling phenomenon and the existence of a boiling front inside wood during continuous and cyclic Vacuum Drying. The Vacuum Drying model was theoretically developed based on an energy balance. The experimental results supported the hypothesis that there is a boiling front during Vacuum Drying. From the boiling front to the surface of the wood, the boiling temperature is lower than the wood temperature, so water in this region boils. From the boiling front to the center of wood, there is no boiling because the pressure inside the wood is higher than the saturation vapor pressure. The boiling front retreats from the surface to the center of the wood as Drying proceeds. The speed of retreat depends on the heat supply and properties of the wood, such as permeability and conductivity.
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Analysis of the Vacuum Drying Rate for Red Oak in a Hot Water Vacuum Drying System
Drying Technology, 2007Co-Authors: Zhangjing Chen, Fred M. LambAbstract:Red oak boards of 76.2 cm (long) × 7.62 cm (wide) × 2.54 cm (thick) were dried from green moisture content (MC) to 7% MC in the hot water Vacuum-Drying system. These boards were dried at the pressure of 12 mm Hg and the temperatures ranging from 30 to 50°C within 25 to 70 h. Drying rates were measured and Drying curves were calculated. The results showed that the Drying rate was higher at higher temperatures. The Vacuum Drying was faster when wood MC was above 30% than when it was less than 30%. The individual samples did not dry at the same Drying rates even at the same Drying conditions because of anatomical variations between boards.
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Analysis of cyclic Vacuum Drying curve
Wood Science and Technology, 2003Co-Authors: Zhangjing Chen, Fred M. LambAbstract:The objective of this research was to analyze the cyclic Vacuum Drying curve within one cycle. Red oak specimens of two different groups, square in cross-section, were used. Group one was comprised of four different thicknesses (2.54, 3.81, 5.08, and 6.35 cm) with a length of 25.4 cm and group two was comprised of three different lengths (12.7, 25.4, and 38.1 cm) with the thickness of 2.54 cm. The specimens were heated to 60°C in the heating oven and then dried in the Vacuum oven at 18 mm Hg. The Vacuum oven was at room temperature (20°C). The Vacuum pump was kept running for 140 min. It was found that the cyclic Vacuum Drying curve consisted of two distinct parts. The fast Drying period lasted about 10 to 15 min. The slow Drying period occurred when the pressure inside wood approached the ambient pressure. Most of the moisture was removed during the fast Drying period.
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Vacuum Drying of small wood components at room temperature
Forest Products Journal, 2001Co-Authors: Zhangjing Chen, Fred M. LambAbstract:This study explores continuous Vacuum Drying at room temperature. Small specimens of red oak were dried at 20°C and at a pressure of about 18 mm Hg. The results showed that small wood components can be Vacuum dried at room temperature with little or no degrade at reasonable Drying rates.
Akio Tagawa - One of the best experts on this subject based on the ideXlab platform.
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impacts of hot air and Vacuum Drying on the quality attributes of kiwifruit slices
Journal of Food Engineering, 2014Co-Authors: Takahiro Orikasa, Shoji Koide, Shintaro Okamoto, Teppei Imaizumi, Yoshiki Muramatsu, Junichi Takeda, Takeo Shiina, Akio TagawaAbstract:Hot air and Vacuum Drying were performed to investigate changes in the moisture content, hardness, l-ascorbic acid content, antioxidant activity, and surface color of kiwifruit samples over the course of the Drying process at temperatures of 50, 60, and 70 °C and a Vacuum Drying pressure of 3.00 kPa. The residual ratio of AsA and the antioxidant activity in the dried kiwifruit samples was 0.75–0.99 and 4.3–5.5, respectively. The l-ascorbic acid changes in the kiwifruit samples during the hot air Drying process followed first order reaction kinetics. Changes in the sample hardness and antioxidant activity were represented by zero-order reaction kinetics. The sample surface color changes after Drying were also measured, and the total color change (ΔE) of the samples at all temperatures and for each Drying process was greater than 12. The sample color changes (Δa*) after Vacuum Drying at each temperature level were significantly (P < 0.01) lower than those associated with hot air Drying.
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Vacuum Drying characteristics of eggplants
Journal of Food Engineering, 2007Co-Authors: Takahiro Orikasa, Yukiharu Ogawa, Akio TagawaAbstract:Abstract The Vacuum Drying characteristics of eggplant were investigated. Drying experiments were carried out at Vacuum chamber pressures of 2.5, 5 and 10 kPa, and Drying temperature ranging from 30 to 50 °C. The effects of Drying pressure and temperature on the Drying rate and Drying shrinkage of the eggplant samples were evaluated. The suitable model for describing the Vacuum Drying process was chosen by fitting four commonly used Drying models and a suggested polynomial model to the experimental data; the effective moisture diffusivity and activation energy were calculated using an infinite series solution of Fick’s diffusion equation. The results showed that increasing Drying temperature accelerated the Vacuum Drying process, while Drying chamber pressure did not show significant effect on the Drying process within the temperature range investigated. Drying shrinkage of the samples was observed to be independent of Drying temperature, but increased notably with an increase in Drying chamber pressure. A linear relationship between Drying shrinkage ratio and dry basis moisture content was observed. The goodness of fit tests indicated that the proposed polynomial model gave the best fit to experimental results among the five tested Drying models. The temperature dependence of the effective moisture diffusivity for the Vacuum Drying of the eggplant samples was satisfactorily described by an Arrhenius-type relationship.
J.j. Irwin - One of the best experts on this subject based on the ideXlab platform.
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Cold Vacuum Drying facility design requirements
1999Co-Authors: J.j. IrwinAbstract:This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified.
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Cold Vacuum Drying facility design requirements
1997Co-Authors: J.j. IrwinAbstract:This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility.
Takahiro Orikasa - One of the best experts on this subject based on the ideXlab platform.
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impacts of hot air and Vacuum Drying on the quality attributes of kiwifruit slices
Journal of Food Engineering, 2014Co-Authors: Takahiro Orikasa, Shoji Koide, Shintaro Okamoto, Teppei Imaizumi, Yoshiki Muramatsu, Junichi Takeda, Takeo Shiina, Akio TagawaAbstract:Hot air and Vacuum Drying were performed to investigate changes in the moisture content, hardness, l-ascorbic acid content, antioxidant activity, and surface color of kiwifruit samples over the course of the Drying process at temperatures of 50, 60, and 70 °C and a Vacuum Drying pressure of 3.00 kPa. The residual ratio of AsA and the antioxidant activity in the dried kiwifruit samples was 0.75–0.99 and 4.3–5.5, respectively. The l-ascorbic acid changes in the kiwifruit samples during the hot air Drying process followed first order reaction kinetics. Changes in the sample hardness and antioxidant activity were represented by zero-order reaction kinetics. The sample surface color changes after Drying were also measured, and the total color change (ΔE) of the samples at all temperatures and for each Drying process was greater than 12. The sample color changes (Δa*) after Vacuum Drying at each temperature level were significantly (P < 0.01) lower than those associated with hot air Drying.
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Vacuum Drying characteristics of eggplants
Journal of Food Engineering, 2007Co-Authors: Takahiro Orikasa, Yukiharu Ogawa, Akio TagawaAbstract:Abstract The Vacuum Drying characteristics of eggplant were investigated. Drying experiments were carried out at Vacuum chamber pressures of 2.5, 5 and 10 kPa, and Drying temperature ranging from 30 to 50 °C. The effects of Drying pressure and temperature on the Drying rate and Drying shrinkage of the eggplant samples were evaluated. The suitable model for describing the Vacuum Drying process was chosen by fitting four commonly used Drying models and a suggested polynomial model to the experimental data; the effective moisture diffusivity and activation energy were calculated using an infinite series solution of Fick’s diffusion equation. The results showed that increasing Drying temperature accelerated the Vacuum Drying process, while Drying chamber pressure did not show significant effect on the Drying process within the temperature range investigated. Drying shrinkage of the samples was observed to be independent of Drying temperature, but increased notably with an increase in Drying chamber pressure. A linear relationship between Drying shrinkage ratio and dry basis moisture content was observed. The goodness of fit tests indicated that the proposed polynomial model gave the best fit to experimental results among the five tested Drying models. The temperature dependence of the effective moisture diffusivity for the Vacuum Drying of the eggplant samples was satisfactorily described by an Arrhenius-type relationship.
