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Phytosanitary heat treatments of Ceratocystis lukuohia and Ceratocystis huliohia-colonized Metrosideros polymorpha wood were evaluated using kilns. Wood poles subjected to a 22- to 34-day dehumidification kiln schedule with a heat treatment to 60[degrees]C to the poles' core. In vacuum kiln trials, logs were heated to 56[degrees]C at 70 percent log radius depth and the temperature maintained for 30 minutes. Neither Ceratocystis species was isolated from heat-treated wood using carrot baiting, whereas both fungi were isolated from control logs held at ambient temperature. Results of this study offer kilnheating as a way to eradicate Ceratocystis fungi from M. polymorpha wood., Ohi'a (Metrosideros polymorpha) is Hawaii's most ecologically significant and culturally valuable native hardwood tree species (Mueller-Dombois et al. 2013). The wood is a highly valued local timber product used for [...]

The focus of this study was to observe the properties of bamboo plastic composites modified with a self-made modifier, 18 acyl-dopamine (0, 0.25, 0.50, 0.75, 1.00, and 1.25 weight percent [wt%] based on the dry weight of bamboo powder). The effects of the modifier were demonstrated by measures of mechanical properties, water absorption, thermal stability, and scanning electron microscopy (SEM). The results revealed that 18 acyl-dopamine could be used as an effective modifier of bamboo powder/high-density polyethylene composites. When the modifier was increased, the toughness of the composite deteriorated, and the strength and rigidity improved. This indicated that when the dosage became higher, the compatibilization became stronger, and the toughening effect became worse. Based on the experimental data, a small dosage modifier acted as a toughening agent; as the dosage increased to 1.0 wt%, the compatibility began to appear. The modifier reacted with the hydroxyl groups on the surface of the bamboo powder, which caused the bamboo powder to absorb less water, so the thickness expansion rate was lowest at 1.25 wt%. The pyrolysis peak of bamboo powder and plastic showed a tendency to be close to each other, indicating that the interface was improving. Based on the equation of Flynn-Wall-Ozawa, as the dosage of the modifier increased from 0.50 to 1.25 wt%, the apparent activation energy also increased. The SEM analysis showed the binding between bamboo powder and the plastic matrix was strongest when the modifier dosage was 1.25 wt%., Bamboo plastic composites have many advantages. Compared with traditional glass fiber and mineral filler reinforced material, bamboo is an environmentally friendly natural filler for composites with lower density and cost, [...]

The purpose of this study was to determine the expression of a kinetic model and the determination of kinetic parameters for cork. Thermal analysis kinetics of cork and impurities (sclereids and lenticels) were studied by thermogravimetric (TG) curves. The Malek method was used to obtain kinetic parameters in this experiment. Reconstruction models of y([varies]) and z([varies]) were compared with standard curves to determine appropriate kinetic models. The results showed that the RO(n) model was suitable to describe the dynamic process of cork, sclereids, and lenticels. The expressions of kinetic models were.f ([varies]) = (1 -[varies]).sup.4,89] for cork, f([varies]) = (1-[varies]).sup.5,82] for sclereids, and f([varies]) = (1--[varies]).sup.5,00] for lenticels. The natural log values In A were 19.56, 28.90, and 28.88 In [s.sup.-1] for cork, sclereids, and lenticels, respectively. Fitting errors of parameters for cork, sclereids, and lenticels were less than 5 percent. The fitted conversion rate and curves of mass fraction were in good agreement with experimental data. Obtaining the kinetic model and parameters provides a basis for prediction of thermal properties of cork., Cork is a natural material obtained from the phellem layer of cork oak. There are mainly two categories of cork oak. Quercus suber is located in the Mediterranean region, and [...]

Abstract The goal of this project was to investigate the efficacy of vacuum--steam technology to sanitize low-quality ash logs and ash firewood. It is difficult to heat treat logs and [...]

Abstract The vacuum-steam treatment of pallets and pallet parts for compliance with the International Standards for Phytosanitary Measures No. 15 regulation was evaluated. Vacuum-steam treatment consists of four steps: (1) [...]

The potential for using vacuum technology to kill larvae of the Asian longhorned beetle (ALB), Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), and emerald ash borer (EAB), Agrilusplanipennis Fairmaire (Coleoptera: Buprestidae), in [...]

Abstract Old house borer larvae, Hylotrupes bajulus, were placed into pieces of red oak (Quercus spp.) at 70 percent moisture content (MC), yellow-poplar (Liriodendron tulipifera) at 7 percent MC, and [...]

FRED M. LAMB [*] ABSTRACT 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 [...]