Suchergebnisse

There is an immediate need to develop and adopt new treatment technologies for eliminating insect pest and tree pathogens from veneer logs moved in trade. This is largely due to the current phase-out of methyl bromide and the uncertainty associated with the efficacy of potential alternatives. Vacuum and steam in combination has a proven and reliable record for commercially sanitizing a variety of commodities, including cotton, spices and textiles among others. This study was designed to evaluate basic parameters of vacuum and steam application on five high value hardwood veneer log species in an effort to ascertain the feasibility of continued treatment development. Relative heating rates to log center, damage and value loss assessment due to treatment, and overall energy used during treatment were recorded for logs treated individually in a flexible polymer chamber. At 200 mm Hg vacuum, time to reach 56 A degrees C for 30 min to core ranged from 17 to 29 h, depending on density and log diameter. End checking varied by species, but veneer sawn from logs was largely unaffected in terms of yield and value. Energy used during treatments ranged from 54 to 205 kWh for individual logs. Results suggest that vacuum and steam as a phytosanitary treatment for hardwood veneer logs has potential and should be explored further. ; USDA-APHIS-PPQUnited States Department of Agriculture (USDA) [11-8130-009-CA] ; This research was funded by USDA-APHIS-PPQ under contract number: 11-8130-009-CA. ; Public domain authored by a U.S. government employee

The term load bridging describes a phenomenon in which the physical interaction between various packaging components acts as a series of discrete loads in a given unit load and adds stiffness to the shipping pallet/load combination. Current pallet design practices often ignore the aspect of load bridging and assume that the pallet payload is flexible and uniformly distributed over the pallet surface. This can influence the load-carrying capacity of the pallet. The study reported in this paper investigated the relationship between the stretch wrap containment force and load bridging in unit loads and the resulting unit-load deflection. The experimental results of this study indicate that an increase in the stretch wrap containment force can improve the unit-load deflection by as much as 81%. The influence of the stretch wrap containment force on pallet deflection is greatest for small packages and pallets with low stiffness. These experimental results provide useful information for realizing more efficient and sustainable unit-load designs. ; US Department of Agriculture (USDA) Forest ServiceUnited States Department of Agriculture (USDA)United States Forest Service [14-JV-1330142-070] ; US Department of Agriculture (USDA) Forest Service, Grant/Award Number: 14-JV-1330142-070 ; Public domain authored by a U.S. government employee

Methyl bromide (MB) fumigation is required for U.S. Quercus log exports due to concern over unintentional spread of Bretziella fagacearum. MB alternatives are needed due to the chemical's ability to damage the earth's ozone layer. Vacuum steam (VS) is an environmentally friendly method that was evaluated for its ability to eradicate B. fagacearum in logs (24 to 61 cm diameter; 1.7 to 1.9 m long) obtained from Q. rubra that had wilted following natural infection (NI) or artificial inoculation (Al). Five replicate loads of two NI and one AI logs were VS-treated at 56 degrees C for 30 min and 60 degrees C for 60 min (at 5.0 cm sapwood depth). Mean frequencies of pretreatment fungus colonization ranged from 12.5 to 24.4% in NI and 29.4 to 45.6% in AI logs based on isolation from wood chips of inner and outer sapwood, respectively, of two disks per log. Frequencies of pathogen DNA detection were similar to those for isolation. No viable pathogen or its DNA were detected in posttreatment logs. Treatment times ranged from 5 to 9 h for the 56 degrees C/30 min schedule and from 8 to 10 h for the 60 degrees C/60 min schedule. Based on these results, VS is worthy of further development as a MB alternative. ; USFS FHP Washington Office ; This research was partially funded by the USFS FHP Washington Office. ; Public domain authored by a U.S. government employee

Shipping pallets often are designed with the assumption that the payload carried is flexible and uniformly distributed on the pallet surface. However, packages on the pallet can act as a series of discrete loads, and the physical interactions among the packages can add stiffness to the pallet/load combination. The term 'load bridging' has been used to describe this phenomenon. The study reported in this paper investigated the relationships of package size, corrugated flute type and pallet stiffness to load bridging and the resulting unit-load deflection. The experimental results indicated that an increase in box size changed the unit-load deflection by as much as 75%. Flute type was found to impact load bridging and the resulting unit-load deflection. Changing the corrugated box flute type from B-flute or BC-flute to E-flute reduces the unit-load deflection by as much as 40%. Also, experimental data indicates that the effect of package size and corrugated board flute type on pallet deflection is the greatest for low stiffness pallets. The results provide information that can be used to design unit loads that use material more efficiently. Copyright (C) 2017 John Wiley & Sons, Ltd. ; USDA Forest Service - Southern Research StationUnited States Department of Agriculture (USDA)United States Forest Service; Ongweoweh Corporation; Center for Packaging and Unit Load Design at Virginia Tech ; USDA Forest Service - Southern Research Station, Ongweoweh Corporation and the members of the Center for Packaging and Unit Load Design at Virginia Tech are gratefully acknowledged for their financial support for this research project. Packaging Corporation of America (PCA) is also acknowledged for the testing material support for this research project. ; Public domain authored by a U.S. government employee