Treesearch

In 1596, the San Pedro, en route from Colombia to Spain, went down in a hurricane off Bermuda, with the loss of its entire cargo. Among the ship’s contents, salvaged between 1950 and 1961, was the most complete collection of 16th century Indigenous weapons recovered from a maritime context, including bows and arrows, darts, stone axes, and two examples of a rare, distinctive style of club. These clubs, featuring a flaring terminal end embellished with recessed two-dimensional geometric design panels, are documented in 16th and 17th century accounts of Indigenous warriors in the Lesser...

In October, month-over-month data declined in the majority of categories. Year-over-year data remain positive in most categories. Single-family permits and starts decreased again, month-over-month and year-over-year. Increasing borrowing costs, slow income growth, and elevated house prices have resulted in a major obstacle for new and existing house sales. October was the ninth consecutive monthly decrease for existing house sales. Single-family construction spending decreased for the sixth straight month.

A high-resolution differential mobility analyzer (DMA) is used for the first time to study the mobility distribution of Polystyrene Latex (PSL) particles. We investigate in particular some unique, nominally 200 nm and 100 nm PSL particles, known by other methods to be unusually monodisperse. The suspensions are electrosprayed after adding ammonium acetate to a concentration of 10 mmol/L. Mobility analysis is carried out after charge reduction with a second electrospray of the opposite polarity. The 200 nm particles typically produce two narrow peaks, with relative intensities that depend...

Because of environmental awareness and regulations and the advent of environmental preferential purchasing, documenting the environmental profiles of building products using life-cycle assessment (LCA) has become a widespread emergent global trend. This study conducted a cradle-to-gate LCA of hardwood lumber production in the southeastern United States. System boundaries in this study included the following production stage information modules: raw material extraction (A1), resource and material transportation (A2), and hardwood lumber manufacturing (A3). Module A1 included forest managemen...

In November, on a month-over-month basis, housing permits declined; this suggests further moderation in single-family activity in the upcoming months. The number of housing completions was the “bright” spot for housing construction. Other year-over-year and month-over-month data were mostly negative.

Concerns over climate change and fossil resources depletion are drivers for increasing efforts to global transition from fossil-based to biobased products. The development of bioenergy and bioproduct systems, however, faces challenges in terms of resource use, environmental impacts, and production costs. Thus, identifying key areas to reduce costs and environmental impacts of biobased products is crucial. Based on the review of recent literature, this study aims to provide insights into the technical feasibility, costs, and environmental impacts of biobased products produced from different...

Although highly desirable, the nature of wood-cellulose in its native state has remained difficult to comprehend. Contrary to the traditional acceptance of wood-cellulose being crystalline, in 2016, the authors’ research found that the cellulose was not crystalline. Here, additional evidence is presented that further supports the non-crystalline model. One of the key pieces of evidence was obtained by 64% H2SO4 hydrolysis of tension- and opposite-aspen woods (TW and OW, respectively). The TW (G-layer rich) yielded significant amount of CNCs (TW-CNCs, 20.7%), the OW yielded a much lower...

Due to concern over climate change, there is an increasing desire to limit new carbon dioxide emissions and to reduce atmospheric carbon dioxide levels. Specific efforts include taxing carbon emissions, capping carbon emissions and selling emissions allowances, and rewarding activities that avoid new carbon emissions or that capture and store carbon from the atmosphere. Cross-laminated timber (CLT) is a relatively new product that enables mass timber construction to replace traditional construction materials in mid-to-high-rise buildings. Wood materials offer substantial “carbon benefits”...

This study evaluated biological resistance, water absorption, and total carbohydrate contents of carbonized woods by contact charring method followed by linseed oil submersion. Charred and control specimens were exposed in laboratory fungal resistance tests to two white – and two brownrot fungi and in mold resistance tests by spraying the surface with a mold spore-suspension comprised of three different mold species. Charred and control specimens were also evaluated for resistance to the eastern subterranean termites. To help understand biological durability results, carbohydrate content...

Measuring the size of cellulose nanomaterials can be challenging, especially in the case of branched entangled cellulose nanofibrils (CNFs). The International Organization for Standardization, Technical Committee 6, Task Group 1 - Cellulosic Nanomaterials, is exploring opportunities to develop standard methods for the measurement of CNF particle size and particle size distribution. This paper presents a summary of the available measuring techniques, responses from a survey on the measurement needs of CNF companies and researchers, and outcomes from an international workshop on cellulose...