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This paper aims to show the potential decay resistance of furfurylated wood and investigate possible eco‐toxicity of such materials produced. This paper deals with the…
This paper aims to show the potential decay resistance of furfurylated wood and investigate possible eco‐toxicity of such materials produced. This paper deals with the environmental aspects and durability of furfurylated wood, both laboratory and field tests are included in the investigations. Results from several decay tests, emission analysis studies and ecotox tests are presented. The results show that furfurylated wood is highly decay resistant. Furthermore, no significant increase in eco‐toxicity of leaching water was found and degradation through combustion does not release any volatile organic compounds or poly‐aromatic hydrocarbons above normal levels for wood combustion. Durability enhancement by furfurylation of wood is not believed to be harmful to the environment. Wood modified with furfuryl alcohol, “furfurylated wood”, is currently being marketed as a non‐toxic alternative to traditional preservative treated wood (wood impregnated with biocides). This paper summarises much of the long term exposure of furfurylated wood ever caried out, and present the first eco‐tox tests on such material ever done.
In manufacturing industries, the levels of inventories at all stages (i.e. raw material, work-in-process and finished goods inventories) indicate the firm's competitive positioning, strategies, internal processes and relationships with suppliers and downstream customers. The authors identify patterns of manufacturing industries based on levels of raw material and finished goods inventories to classify inbound and outbound supply chain strategies.
The authors review literature on supply chain inventory strategy and perform cluster analysis to analyze patterns of manufacturing industries based on manufacturing industry data collected from US Census of Bureau. Following Porter's Five Forces Model, the authors perform in-depth case studies of four representative industries to analyze factors driving supply chain strategies, including industry intensity of rivalry, threat of new entrants, threat of substitutes, bargaining power of suppliers, and bargaining power of buyers.
This study identifies three streams of research on supply chain strategy: Fisher's model and its variations, lean and agile paradigms, and push/pull systems. It finds that whether an industry shows low or high raw materials or finished goods inventories depending on its products, processes, and the dynamics of all forces described in the Five Forces Model.
This study is not able to include supplier selection, production strategies, warehousing and distribution, and even product design into the analysis of supply chain strategy due to data limitation. This study classifies industries based on average inventory levels of raw materials and finished goods, while inventory levels and supply chain strategies for specific firms may vary significantly within each industry.
This study contributes to the supply chain management literature by providing a parsimonious framework of mapping inbound and outbound supply chain inventory strategies, and the results based on the analyses of all US manufacturing industries provide a baseline picture for supply chain management professionals with manufacturing firms.
The library of the International Tin Research Institute houses a unique collection of material on all aspects of tin. The wide range of subjects covered, from 18th century…
The library of the International Tin Research Institute houses a unique collection of material on all aspects of tin. The wide range of subjects covered, from 18th century tinplate production to modern organotin biocides, and the information explosion of recent years, has necessitated the introduction of a new, hierarchical, indexing system. Lack of storage space in the library has been overcome by the use of a microfilm reader/printer and by storing abstracts obtained from abstract journals rather than obtaining full copies of papers immediately. The other information services of the Development Department include the production of a quarterly journal, an annual report, various technical publications and technical films. A free and confidential advisory service is offered to industry by the Institute.
Most of the building industry has benefitted from new technical developments and by the introduction of specifications and standards. External woodwork is no exception.
Organotin compounds are well established as fungicides in organic solvent‐based wood preservative formulations for out‐of‐ground contact applications. In this context investigations have continued throughout the year on the biocidal effectiveness of alternative candidate tributyltin de‐rivatives towards two wood‐destroying fungi Conio‐phora puteana and Co dolus versicolor. In addition, a mini‐block soil contact burial test has been initiated, in conjunction with the Building Research Establishment, Princes Risborough Laboratory, designed to assess the activity of three organotin compounds against soft rot soil fungi. This type of test is useful for screening candidate chemicals for use in the preservation of timber in ground‐contact situations. Initial results with tributyltin compounds, including water‐soluble tributyltin ethanesulphonate, are much better than expected. Biological and analytical data have been obtained for accelerated ageing procedures (leaching by water or elevated temperature) on T.B.T.O.‐treated Scots pine sapwood. It has been demonstrated that heating (to 60°C) influences the breakdown of the tributyltin preservative to lower alkylated products. Results of a study, in collaboration with the Swedish Wood Preservation Institute, Stockholm, on timber taken from an out‐of‐ground contact trial indicate that there is a strong correlation between weight losses of samples exposed to Coniophora puteana and the amount of T.B.T.O. present in the wood. Experiments are in hand to establish the reason why the total tin content appears to decrease with time as degradation proceeds. Chemical analyses were also carried out on blocks of Pinus sylvestris treated with a limited number of other tributyltins, Bu3SnX, to assess the effect of the X group on degradation.
Research into various aspects of organotin compounds in wood preservation has continued.
Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone…
Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone, brick, metal and plastic are all derived from exhaustible mineral sources.
The International Tin Research Council has recently published its Annual Report for 1982, which contains a lengthy report on its work on organotin chemistry. Of particular interest to readers of this journal are the accounts of work done on organotin‐based antifouling paints, and organotins in wood preservation, which are republished below. The full report is obtainable from the International Tin Research Institute at Fraser Road, Greenford, Middx UB6 7AQ.
Untreated timber exposed to the weather will discolour and degrade under the influence of physical and biological agencies. If the natural appearance of exposed timber is to be preserved, it is necessary to apply some form of surface treatment. This digest discusses the selection, use and maintenance of exterior wood stains, varnishes and other types of external natural finish. Before considering the different types of natural finish in detail, it first deals with the characteristics of the wood substrate that have a significant influence on their performance. The digest brings up to date the information contained in an earlier (now withdrawn) digest, No. 182.
The purpose of this paper is to determine the effect of Imersol Aqua impregnation of Scotch pine, Oriental spruce, and Uludağ fir on the surface adhesion strength of…
The purpose of this paper is to determine the effect of Imersol Aqua impregnation of Scotch pine, Oriental spruce, and Uludağ fir on the surface adhesion strength of various types of varnishes. The finding obtained would benefit the manufacturers of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.
For this purpose, test samples were prepared from Scotch pine, Oriental spruce, and Uludağ fir woods that met the requirements of ASTM D 358. The samples were impregnated with Imersol Aqua using short‐, medium‐, and long‐term immersion techniques according to ASTM D 1413 and the manufacturer's instructions. After impregnation, surfaces were coated with synthetic, acrylic, polyurethane, and water‐based varnishes in accordance with ASTM D 3023 standards. After the varnishing process, the adhesion strength of the samples was determined in accordance with ASTM D 4541.
It was also found that among the wood samples, the adhesion strength was highest in Scotch pine and lowest in Uludağ fir. The synthetic varnish produced the highest adhesion strength, whereas polyurethane and acrylic varnishes had the lowest adhesion strength. The adhesion strength was highest after medium‐term immersion and lowest after long‐term dipping. The highest adhesion strength (4.299 MPa) was produced by a combination of Scotch pine, medium‐duration immersion, and the use of a wood‐based varnish. The lowest adhesion strength (2.090 MPa) resulted from the combination of Uludağ fir, long‐term immersion, and a water‐based varnish.
Impregnating woods using materials with appropriate water repellent, biotic, and abiotic effects before the application of varnishes and paints is important for long‐term protection against photochemical degradation, dimensional changes, biological factors, and fire.
The effect of a varnish on surface adhesion strength can determine the usefulness of the varnish.
Improving surface adhesion of some varnishes via medium‐term impregnation with Imersol Aqua impregnation should be used on Scotch pine, Oriental spruce, and Uludağ fir woods which could be used in the manufacturing of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.