Your search resulted in 6 documents.
A field evaluation of modified and unmodified alkylammonium compounds
1987 - IRG/WP 3436
Laboratory soil block studies of alkylammonium compounds (AAC's) at Forintek and other research establishments have shown that they can prevent decay by standard wood-destroying fungi. Their performance in field tests, however, has been disappointing. Following investigation of possible causes for this poor field performance, stakes treated with modified AAC's were installed at Westham Island. All three formulated AAC's have shown greatly improved performance over the unmodified material. The inclusion of ammoniacal copper oxide with Barquat MB 80 (an alkyldimethylammonium chloride) is providing excellent performance after four years with log scores of 100 at retentions of 7 kg/m³ (total preservative). Stakes treated with the same AAC modified with tributyltin chloride to a retention of 1.2 kg/m³ (total preservative) had a log score of 87 after five years.
J N R Ruddick
Improved PEC preservatives with added biocides
1985 - IRG/WP 3322
Biocidal chemicals have been incorporated into formulations within the broad framework of pigment emulsified creosote (PEC) to provide novel potential multi-purpose preservatives. Preparations of PEC plus TCMTB, Boracol 40, copper ethanolamine nonanoate, Quatramine 80, arsenic trioxide, Troysan Polyphase, and CCA have been formulated and assessed for preserving ability in soil-jar and Accelerated Field Simulator tests. In addition, a cationic oil-in-water emulsion preservative combination of PEC and CCA (PECCA), and an anionic formulation of TCMTB with PEC (PECBUS) have been manufactured in 400 L quantities to treat hardwood pole stubs and pine posts. The results indicate the potential of these improved second generation PEC-based preservatives to provide low-creosote containing treatments able to protect commodities against biodeterioration as well as provide dry, clean surfaces.
H Greaves, C-W Chin, J B Watkins
IRG Conference Awards
1978 - IRG/WP 80
Ammoniacal wood preservative for use in non-pressure treatment of spruce and aspen poplar. Part 1
1984 - IRG/WP 3273
End-matched lumber of Picea glauca (Moench)Voss (white spruce) and Populus tremuloides Michx. (aspen poplar) timbers was treated by a thermal diffusion process in open tank treating vessels using an ammoniacal copper-arsenate wood preservative. The process proved technically feasible with respect to controlling the vapourization of ammonia from open tanks during treatment at high temperatures. Treatments of 48 hours or more on unseasoned and partially dried lumber produced net oxide retentions above that required by the Canadian Standard Association CSA-080 wood preservation standard for timber in above ground contact situations. Although preservative penetrations did not meet the penetration requirements (10 mm), of the CSA 080.2 standard for ground contact, five of the seven non-pressure charges on spruce lumber had heartwood penetrations greater than 7 mm in depth. A 24-hour treatment on air-dried spruce had penetrations equivalent to a five-hour vacuum-pressure treatment. Retention was adequate for above-ground exposure
C D Ralph, J K Shields
The effect of Tween 80 on the growth, morphology, and enzyme secretion of Postia placenta
1990 - IRG/WP 1456
The nonionic surfactant Tween 80 (polyethylene oxide sorbitan mono-oleate) has been reported to increase enzyme production and/or secretion in bacteria and fungi. Such a procedure could greatly facilitate research into the physiology of wood-decay fungi since quantities of available enzyme are often limiting. The brown-rot fungus Postia placenta was grown in a synthetic medium supplemented with 0, 0.01, 0.05, 0.1, 0.2, and 0.4% Tween 80. The addition of even the lowest percentage of Tween significantly increased mycelial dry weight and prevented the formation of aerial hyphae. With the exceptions of ß-D-glucosidase and ß-D-galactosidase, extracellular carbohydrate-degrading enzyme production did not change. Levels of xylanase, carboxymethylcellulase, laminarinase, and ß-D-galactosidase remained unaffected by the presence of Tween. Some factor other than secretion mechanisms, such as microelement or nitrogen availability, is probably limiting production of these enzymes.
J A Micales
Selección de hongos reductores de extraíbles del género Ophiostoma, mediante la prueba de opacidad Tween 80
2009 - IRG/WP 08-10677
Wood extractives cause diverse problems in the industry of the wood, the pulp and the paper; among others, they produce pitch deposition during the pulp manufacturing, generating important economic losses for the sector. Recently, to mitigate these effects, it has been proposed the biological pretreatment of chips and the solid wood with colorless fungi of different species from genus Ophiostoma. Although to the date the results have been promissory, these have shown the necessity to look for new strains that improve effectiveness of the biological treatment. The procedures used for the search of new reducing strains of extractives, are extensive and highly intensive in the use of resources. The aim of the present study was the search of a simple and fast methodology that it allows to find a test concerning laboratory that allows establishing a correlation between these tests and the effectiveness of the biological pretreatment on industrial scale. The detection of strains of fungi with the majors production rates of lipolitic enzymes appears on the matter like an interesting alternative. The results of opacity of Tween 80 test showed that by means of the measurement of the radius of the halos produced in this solid means, the strains of the species O. floccosum has better production rates of lipolitic enzymes that the strain of the species O. piliferum and O. piceae, which agrees with the results obtained for the reduction of extractives in wood of radiata pine. Extraíbles de la madera provocan diversos problemas en la industria de la madera, la pulpa y el papel; entre otros, provocan la generación de pitch durante el proceso de pulpaje, generando importantes pérdidas económicas para el sector. Recientemente se ha propuesto, para mitigar estos efectos, el biotratamiento de las astillas y de la madera sólida con cepas albinas de distintas especies del género Ophiostoma. Aunque a la fecha los resultados han sido promisorios, éstos han mostrado la necesidad de buscar nuevas cepas que mejoren las bondades del biotratamiento. Los procedimientos utilizados para la búsqueda de nuevas cepas reductoras de extraíbles, son extensos y altamente intensivos en el uso de recursos. La presente investigación tiene como propósito la búsqueda de una metodología simple y rápida que permita encontrar un ensayo a escala de laboratorio que permita establecer una correlación entre estos ensayos y la efectividad del biotratamiento a escala real. La detección de cepas de hongos con las mayores tasas de producción de enzimas lipolíticas aparece al respecto como una interesante alternativa. Los resultados de la prueba de opacidad del Tween 80 mostraron que mediante la medición del radio de los halos producidos en este medio sólido, las cepas albinas de la especie O. floccosum tienen mejores tasas de producción de enzimas lipolíticas que las cepas de las especies O. piliferum y O. piceae, lo que concuerda con los resultados obtenidos para la reducción de extraíbles en madera de pino radiata.
P Herrera, J Navarrete, C Breuil, E Werner