Treesearch

This paper compares the Iosipescu shear test to its derivatives: the Wyoming, FPL, and Idaho shear tests.

Beetle-killed spruce can be used as a fiber source for papermaking. The presence of sap rot is a key indicator of pulpability, but other factors may also be important.

Machine lumber grading has been applied in commercial operations in North America since 1963, and research has shown that machine grading can improve the efficient use of wood. However, industry has been reluctant to apply research findings without clear evidence that the change from visual to machine grading will be a profitable one. For instance, mill managers need guidelines on machine grading. This report seeks to document such guidelines so that lumber mills can determine the feasibility of machine grading for their products. The first part of this report discusses the principles of...

Log-sort yards provide better utilization and marketing with improved value recovery of currently available timber resources in North America. Log-sort yards provide many services in marketing wood and fiber by concentrating, merchandising, manufacturing, sorting, and adding value to logs. Such operations supply forest products firms with desired raw materials, which helps improve a company’s bottomline by reducing the number of marginal logs processed. Successful log-sort yards are self- sufficient and have a good business plan, well-established markets, and a steady supply of wood....

This presentation discusses a success story of cooperative research and development (R&D) and commercialization of ultrasonic detection technology for locating internal defects in lumber. The R&D work described in this paper is the result of a unique federal laboratory and private sector partnership between the USDA Forest Service, Forest Products Laboratory (FPL) and Perceptron, Inc., a manufacturer of scanning systems for the forest products industry. Efforts by research engineers at the FPL on applying ultrasonic nondestructive evaluation (NDE) methods proved successful in laboratory...

A series of batch isotherm tests was performed with alfalfa and juniper fibers to evaluate the effectiveness in filtering toxic heavy metals from stormwater. The adsorption of the heavy metal ions on the alfalfa and juniper fibers was strongly dependent on the equilibrium pH value of the solution. The change in sorption rate over time showed that two different sorption processes occurred a fast ion exchange followed by a chemisorption. Heavy metals were less sorbed when they are in solution together than when they exist alone in solution; however, the total adsorptive capacity of the...

Conferences covered in this semiannual review include the TAPPI Recycling Symposium and the 9th PTS/CTP Deinking Symposium. The intent of this feature is to present a synopsis of the significant research results and industry ideas related to paper recycling reported at these conferences. Due to space constraints, we are not able to cover all of the presented papers in detail. Readers are encouraged to obtain the original articles for more information.

Dehydropolymerization of [rho]-hydroxycinnamyl alcohols with manganese(III) acetate in either aqueous acetic acid or pyridine resulted in dehydropolymers (DHPs) that more closely approximate the structure of natural lignins than do DHPs produced by enzymic techniques. The 13C NMR spectrum of a "biomimetic" guaiacyl-DHP (G-DHP) from coniferyl alcohol was very similar to that of a lignin isolated from spruce wood, unlike a corresponding spectrum of a G-DHP prepared by a conventional enzymic technique. A similar comparison between a biomimetic guaiacyl/syringyl DHP (GS-DHP), a conventional...

The work described in this paper culminates an investigation into the treatability of five Appalachian hardwood species. Previous papers have described work using the waterborne preservatives CCA-C and ACQ-B. This paper details the results of pressure treatment with creosote and Timbor®. Six-inch long nominal two-by-four samples of red maple, yellow-poplar, red oak, hickory, and beech were end-sealed and vacuum/pressure treated. Two borate treatments were tested: wrapped in plastic or not wrapped. Measurements were taken of minimum and maximum penetration, percentage of cross-sectional...

A new instrument and technique developed at the USDA Forest Service, Forest Products Laboratory to evaluate the adhesion of inks on paper was used to study toner loss on copier papers. This instrument creates a fold with a very small radius in the printed region of a paper specimen. This fold is repeatedly rolled through the specimen until the desired degree of wear is induced. If the radius of the fold is small enough, a critical strain is reached where the toner layer fractures cohesively. Subsequent cycling will cause adhesive failure of the toner as fragments are peeled from the paper...