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This study was carried out to determine the potential of coagulation pretreatment with organic or inorganic coagulants to improve ultrafiltration performance during processing of wash deinking effluents containing flexographic inks. Wash filtrate effluents generated from mixtures of old flexographic and offset newspapers and old magazines were pretreated with a cationic coagulant and alum before ultrafiltration. Membrane performance was assessed from permeate flux, fouling rate, and ease of membrane regeneration. Coagulation pretreatment of wash filtrate effluents with a commercial...

This review summarizes patents related to paper recycling that were issued during the first 6 months of 1999. The two on-line databases used for this search were C1aims/U.S. Patents Abstracts and Derwent World Patents Index. This semiannual feature is intended to inform readers about the latest developments in equipment design, chemicals, and process technology for recycling paper. This review contains only brief summaries of the inventions. For complete information, readers will need to access the full texts of specific patents. We organized this review into the following broad categories...

Connections between steel side plates and white oak glued-laminated beams subjected to tension perpendicular-to-grain stresses were tested to failure. The beams were then repaired with five different configurations using two sizes of lag screws, with and without steel reinforcing plates. The repaired beams were re-tested to failure. Results indicate that in all cases the repaired beams had greater ultimate loads than did the original beams. Results also indicate that lag screws without the reinforcing plate are sufficient for repair.

A new delignification technology based on the use of polyoxometalates (POMs) as delignification agents is under development at the USDA Forest Service, Forest Products Labotatory (FPL), in Madison, Wisconsin. These reagents are chlorine free and can be used under conditions wherein they oxidize lignin and chromophores in wood pulp fibers while leaving the cellulose undamaged. Their promise is enhanced by the fact that they can be re-activated with oxygen under conditions that result in oxidation of the organic byproducts of the delignification process. Thus, they can be continuously...

Phenolic compounds are important in the production of bonded-wood products. Phenolic compounds in addition to phenol and resorcinol are potential alternative feedstocks for producing adhesives. The reactivity of a wide variety of phenolic compounds with formaldehyde was investigated using semi-empirical and ab initio computational chemistry methods. Results of these calculations were compared with experimental data. The results indicate that ab initio computational chemistry methods coupled with newer methods for calculating atomic charges can be used to explain the relative reactivities...

Kenaf Tainung 1 cultivar was grown in Madison, WI in 1994. The ratio of core to bast fiber, total plant yield, protein, ash, fiber length, extractives, lignin, and sugar content were determined as a function of growing age. Ash, protein, extractives, L-arabinose, L-rhamnose, D-galactose, and D-mannose contents decreased while lignin, D-glucose and D-xylose content increased as the plant matured. Fiber length increased in the early part of the growing cycle, then decreased, then increased again as the plant matured.

A new species of Cuphophyllus in sect. Virginei is described and illustrated from the Lesser Antilles, and comparisons made with Camarophyllus niveicolor.

This section addresses the design of two types of glulam timber bridges : beam bridges with transverse decks and longitudinal glulam deck (slab) bridges. The material presented in the section is based on the 1992 edition of the AASHTO Standard Specifications for Highway Bridges (AASHTO specifications), including interim specifications through 1993. When specific design requirements or criteria are not addressed by that specification, recommendations are based on referenced standards and specifications or commonly accepted design practice. Because AASHTO specifications are periodically...

When left untreated in many outdoor applications, wood becomes subject to degradation by a variety of natural causes. Although some trees possess naturally occurring resistance to decay (Ch. 3, Decay Resistance), many are in short supply or are not grown in ready proximity to markets. Because most commonly used wood species, such as Southern Pine, ponderosa pine, and Douglas-fir, possess little decay resistance, extra protection is needed when they are exposed to adverse environments. Wood can be protected from the attack of decay fungi, harmful insects, or marine borers by applying...

A *Horn of Plentya awaits veneer producers who attack problems with the right strategies, reduce wood costs, upgrade products.