Treesearch

It has been well established that stainless steel nails have superior corrosion performance compared to carbon steel or galvanized nails in treated wood; however, their mechanical fastening behavior is unknown. In this paper, the performance of stainless steel nails is examined with respect to two important properties used in wood connection design: withdrawal strength and nail bending yield strength. Different nail diameters, wood specific gravities, and nail manufacturers were examined. The current withdrawal design equations, developed from carbon steel nail data, overpredict the...

Actualmente el comercio mundial se realiza a gran escala, estableciéndose requisitos cada día más exigentes, donde los productores y consumidores requieren realizar transacciones comerciales con unamayor de confiabilidad, y donde la calidad de los productos y servicioses un aspecto crítico en las actividades comerciales.

Actualmente, debido a la globalización, las relaciones comerciales crecen rápidamente, las cuales son más exigentes día a día; dicho desafío requiere que las organizaciones mejoren sus procesos y productos permitiendo realizar transacciones con un alto grado de confiabilidad, con el debido respaldo de la calidad de los productos y/o servicios que se comercializan.

We report on the performance and the characterization of top-gate organic field-effect transistors (OFETs), comprising a bilayer gate dielectric of CYTOP/ Al2O3 and a solution-processed semiconductor layer made of a blend of TIPS-pentacene:PTAA, fabricated on recyclable cellulose nanocrystal−glycerol (CNC/glycerol) substrates. These OFETs exhibit low operating voltage, low threshold voltage, an average field-effect mobility of 0.11 cm2/(V s), and good shelf and operational stability in ambient conditions. To improve the operational stability in ambient a passivation layer of Al2O3 is grown...

Understanding and controlling molecular-scale interactions between adhesives and wood polymers are critical to accelerate the development of improved adhesives for advanced wood-based materials. The submicrometer resolution of synchrotron-based X-ray fluorescence microscopy (XFM) was found capable of mapping and quantifying infiltration of Br-labeled phenol−formaldehyde (BrPF) into wood cell walls. Cell wall infiltration of five BrPF adhesives with different average molecular weights (MWs) was mapped. Nanoindentation on the same cell walls was performed to assess the effects of BrPF...

The FEMA P-807 Guidelines were developed for retrofitting soft-story wood-frame buildings based on existing data, and the method had not been verified through full-scale experimental testing. This article presents two different retrofit designs based directly on the FEMA P-807 Guidelines that were examined at several different seismic intensity levels. The effects of the retrofits on damage to the upper stories were investigated. The results from the hybrid testing verify that designs following the FEMA P-807 Guidelines meet specified performance levels and appear to successfully prevent...

The objective of this study was to document current areas of subterranean termite activity in Wisconsin and to evaluate genetic characteristics of these northern, peripheral colonies. Here, amplified fragment-length polymorphism was used to characterize levels of inbreeding, expected heterozygosity, and percent polymorphism within colonies as well as genetic structure among populations sampled. Genetic analysis revealed two species of termites occur in Wisconsin, Reticulitermes flavipes (Kollar) and Reticulitermes tibialis Banks, both found in the southern half of the state. Colonies of...

Research was conducted to evaluate the decking performance of northeastern United States wood species treated with copper based preservatives. Decking specimens were treated with one of four wood preservatives and exposed near Madison, Wisconsin. Specimens were evaluated for biological attack and dimensional stability. After 10 years, none of the preservative treated specimens had fungal decay. All of the untreated Southern Pine specimens were severely decayed within 5 years, but untreated specimens of other species were much slower to decay. Surface mold was most commonly observed on...

New noncontact technologies have been developed and implemented for determining as-built condition and current dimensions for a wide variety of objects and buildings. In this study, a three-dimensional laser scanner was used to determine the dimensions and visual condition of a historic bridge in the Amnicon Falls State Park in northern Wisconsin. 3D scanning provides millions of data points of information about the bridge being inspected. The point clouds of data collected depict all visible aspects and actual dimensions of the bridge. This information can be used to determine areas of...

This report summarizes information on nondestructive testing and evaluation of wood. It includes information on a wide range of nondestructive assessment technologies and their uses for evaluating various wood products.