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1.
Although Malaysia is a major producer and exporter of wood products in the world, the status of wood products certification in the industry is relatively unknown. Therefore, a study was carried out to assess the status of chain of custody certification among wooden furniture manufacturers using a structured questionnaire to interview firms who had participated at the annual Malaysian International Furniture Fair (MIFF). Results collated indicate that the readiness to adopt chain of custody certification among wooden furniture manufacturers was low. The lack of price premiums, limited market potential and high cost was cited as the primary reasons deterring furniture manufacturers from adopting chain of custody certification. Furthermore, the use of plantation wood resources, such as Rubberwood (Hevea brasiliensis), perceived to be certified wood resources, reflects the lack of understanding among the manufacturers. This study shows that an increasing adoption of chain of custody certification among wooden furniture manufacturers in Malaysia can be realized in the market organisation, especially with regards to price premiums and market requirements.  相似文献   

2.
Although Europe represents a major market for Ghana, information on how local companies are addressing chain of custody certification is scarce. A survey of 103 timber firms, in particular, was conducted in order to determine the current status of chain of custody certification in Ghana. Results collated indicate that the readiness to adopt chain of custody certification among the sector was low. The lack of stakeholders?? awareness and price premium was cited as the primary reasons deterring the sector from adopting certification. This study analysis suggests that company size is an important variable to be considered when analyzing the adoption of chain of custody certification by timber companies. This study shows that an increasing adoption of chain of custody certification among the sector in Ghana can be realised with good stakeholder consultations and resource rights.  相似文献   

3.
The purpose of this research was to evaluate selected lumber attributes, species preferences, and lumber use properties among secondary wood manufacturers in the United States. Our sample included producers of kitchencabinets, furniture, doors, windows, and molded products who attended regional and national wood manufacturing events. More than 51% of respondents had annual sales of less than $500000, and the median company size was five employees. Results are presented for 17 selected lumber attributes, and indicate that appearance-related attributes were generally the most important, and that use of certified lumber was generally the least important. Price-related attributes (including low price and price stability) were generally intermediate in importance. There were statistically significant differences among geographic regions for four of the attributes, and among business types for three of the attributes. The most popular species for use by secondary manufacturers included the oaks, maple, and cherry, and there were strong preferences for kiln-dried, 4/4 (2.54 cm) lumber having random length and width.  相似文献   

4.
Relative to the enormous acceptance of the ISO 9000 quality standard, the ISO 14001 environmental management certification has been met with only moderate enthusiasm among industrial facilities. The literature on corporate motivation for ISO 14001 participation is relatively modest considering the enormous number of publications reviewing other aspects of its adoption and implementation. It would seem that the present "marketing" package supporting ISO environmental commitments does not seem to offer sufficiently persuasive incentives for increased sales, either domestically or internationally. While researchers assume that a higher export rate of companies is positively associated with higher ISO participation rates, there have been very few empirical studies that support this inference, and conclusions have not been based on data taken from importing countries orfrom a systematic evaluation of expressed corporate preference for products sold by ISO 14001 certified companies. The present study reports the results of a survey to firms in six countries that are Israel's leading trade partners, importing chemicals, textiles, and produce. The survey results confirm that while the international market still considers price and quality as the paramount factors in selection of suppliers, environmental management systems (EMS) are an important feature that is frequently taken into consideration. EMS certification appears to signify a supplier who is managing the business well and exhibiting ethical responsibility. The European market proved to be more environmentally conscious than those in other industrialized parts of the world. EMS offer a particularly valuable advantage for producers wishing to reach European markets. As policy-makers seek to expand the voluntary adoption of EMS, a clear advantage for exporters should be highlighted among national industries.  相似文献   

5.
Strength of wood is normally measured in ramp load experiments. Experience shows that strength increases with increasing rate of testing. This feature is considered theoretically in this paper. It is shown that the influence of testing rate is a phenomenon, which depends on the quality of the considered wood. Low quality wood shows lesser influence of testing rate. This observation agrees with the well-known statement made by Borg Madsen that weak wood subjected to a constant load, has a longer lifetime than strong wood. In general, the influence of testing rate on strength increases with increasing moisture content. This phenomenon applies irrespective of the considered wood quality such that the above-mentioned order of magnitude observations between low and high quality wood are kept.  相似文献   

6.
Slab milling with a conical shaped milling tool and slab milling with a face milling tool are wood machining techniques which meet the current requirements of wood machining and processing (e.g. changing batch sizes, flexible machines and equipment). That is why the Institute for Machine Tools at University of Stuttgart has already conducted comprehensive basic research in this field (Heisel 1997). Research on slab milling with a face milling tool was especially promoted as an alternative to slab milling with a peripheral milling tool (also known as planing) due to its low noise emission and low energy consumption. Amongst others, slab milling with a face milling tool as pre-milling procedure when calibrating wood-based panel products was examined under technical and economic aspects. The results showed higher service life and continuously better surfaces when choosing the right geometry of the cutting tools as compared to conventional slab milling with a peripheral milling tool. Notwithstanding the high costs, diamond cutting edges are more cost-effective than carbide insert tips due to their longer service life (Heisel 2004).  相似文献   

7.
浙江省吸油烟机企业实施CCC认证存在问题与对策   总被引:1,自引:1,他引:0  
楼丽容  陈勇 《轻工机械》2010,28(3):116-119
浙江省是中国吸油烟机生产大省,随着CCC认证开展,越来越多企业发现在实施CCC认证过程中,建立CCC体系文件不能指导实际操作,产品一致性得不到有效控制,ODM/OEM难控制等问题,导致企业质量体系运行失效,不能正常维持证书有效性,产品不能出厂销售。面对诸多问题,企业应如何应对呢。文章从浙江省吸油烟机企业建立和运行2个阶段对CCC认证体系存在的问题进行分析,提出了树立正确认证观、产品一致性全过程管理和ODM/OEM管理等解决问题对策和建议。参10  相似文献   

8.
The forest and wood industry in Japan require the development of automation technology to produce high-quality lumber from medium-quality sugi (Cryptomeria japonica D. Don) logs. This study investigates the influence of pith location on the warp of lumber. While drying reduced the bow of lumber drastically its crook remained almost unchanged. Therefore, an effective sawing method to reduce crook was sought after. Crook measured immediately after sawing increased as the distance between the center of the lumber and the pith location along the width of lumber increased. A sawing method which takes pith location into account was concluded to be effective in reducing crook. Based on these results, a new sophisticated sawing procedure to produce high-quality lumber is proposed.  相似文献   

9.
Knowledge about the development of the internal gas pressure during hot pressing of wood-based composites is important for the optimization of panel properties and production speed. The gas pressure heavily affects the thermodynamic conditions inside the wood furnish mat, and a too high maximum value at press opening might cause an impairment of the panel properties. In this paper, gas pressure and temperature measurements inside a particle mat while passing through a continuous hot press are presented for the first time. The measurements were performed with a transportable system, consisting of a steel tube attached to a miniature pressure transducer and a data logger. The particleboards had a target thickness of mainly 16 mm, but also of 28 mm and 38 mm, respectively. The measurements show a distinct horizontal gas pressure distribution in both directions, in production direction and across the mat’s width. In contrast, cross-sectional gas pressure gradients were only visible inside the panels after leaving the press. By comparing the gas pressure curves measured for particleboard with those for medium density fiberboard (MDF), characteristic differences became evident. Overall, the gas pressure is higher in MDF compared to particleboard. Finally, a comparison between the gas pressure levels measured for three different panel thicknesses showed a clear relation between panel thickness and gas pressure, with a decreasing panel thickness resulting in an increase in gas pressure. The results of this paper will contribute to our understanding about the events inside wood furnish mats during continuous hot pressing.  相似文献   

10.
An alternative method to quantitatively determine the wood failure percentage on shear test specimens was developed, experimentally tested and successfully applied to specimens with typical combinations of adhesive types and wood species used by the glulam industry in Switzerland. The method consists of a staining technique for a better differentiation of wood fibers and adhesive, and an image processing procedure for a standardized estimation of the fractured surface ratio covered by wood fibers and adhesive, respectively. The semi-automatic method allows for a more objective determination of wood failure percentage and is suitable for quality control in the glulam industry.  相似文献   

11.
This study utilises Computer Tomography (CT-scanning) to characterize the capillary water uptake in wood specimens. CT-scanning makes it possible to study the capillary rise of water as a function of height in wood specimens after a specific exposure time. The study has also included the development of a theoretical model, which determines the capillary characteristics of wood in relation to its structure. The model developed was tested using experimental results, considering the capillary suction height and the water content change after a specific time as boundary values. A comparison between the theoretical model and the experimental results shows that not all the cells in the wood samples take part in the capillary water transport. It also appears that there is a structural resistance to capillary flow.  相似文献   

12.
Mechanical properties of wood treated with PF-pyrolytic oil resins   总被引:1,自引:0,他引:1  
Jack pine and sugar maple wood samples were treated in a two-step process that involved first a copper chloride or a copper chloride-sodium borate mixture and then a phenol-formaldehyde resin containing a certain percentage of softwood bark pyrolytic oil. Various controls were also prepared for comparison. The modulus of rupture (MOR) of jack pine samples was generally negatively affected by the treatment, the observed values being lower than those of the controls. These values were statistically lower or equal to those of untreated samples. On the other hand, the modulus of elasticity (MOE) of treated jack pine samples was not found to be statistically different from that of the untreated wood. Mechanical properties behaved in a similar way for sugar maple wood. Unlike the other treatments, copper chloride–sodium borate and the resin containing 85% of pyrolytic oil as phenol substitute appeared to slightly improve the mechanical properties of both wood species even if not significantly so. Treatment with PF-pyrolytic oil resin resulted in similar or slightly better mechanical properties when compared to CCA-treated wood. The amount of treating water soluble salts retained in samples after the first treatment had a significant impact on MOR of both wood species and on MOE of sugar maple.  相似文献   

13.
Wood surface discolouration due to simulated indoor sunlight exposure   总被引:1,自引:0,他引:1  
Wood surface colour is a very important quality criterion in the utilisation of wood, especially in indoor applications. In this study, an attempt was made to analyse wood surface discolouration due to artificial indoor light irradiation of the most frequently traded wood species in Europe altogether. Sixteen wood species, twelve hardwood and four softwood species, were exposed for 120 hours to a xenon-arc lamp equipped with a 3 mm window glass filter, in order to simulate natural sunlight behind a window glass. Eleven wood species were chosen and further exposed to irradiation for up to 600 hours. Colour measurements were performed by means of a colorimeter device on exposed and non-exposed areas of the samples. Using the CIE-L*a*b* colour measuring system, wood surface discolouration was measured and calculated according to ?L*, ?a*, ?b* and ?E* values. An idea of the different behaviour of these species and how they relate to each other could be given.  相似文献   

14.
Heat treatment of wood has attracted a lot of attention both in Europe and recently in North America as an environmentally-friendly wood-protection method. The untreated wood is hydrophilic (high affinity for water). During the heat treatment, wood becomes more and more hydrophobic (low affinity for water) with increasing heat treatment temperature. As a result, it becomes more resistant to biological attacks. Furthermore, it becomes dimensionally more stable compared to untreated wood. Its hardness increases. As the wood becomes more hydrophobic, its wettability by water decreases. The effect of heat treatment is different for each species. Studying the wetting characteristics of heat treated wood gives a good indication of the heat treatment effects on certain wood properties which are related to its degree of hydrophobic character. The aim of this work was to study the characteristics of dynamic wetting process for two different heat-treated North American wood species white ash (Fraxinus americana) and soft maple (Acer rubrum). Contact angle measurements before and after heat treatment showed a significant increase in wood hydrophobicity. Advancing contact angles of a water drop were in all cases higher for heat-treated wood than for untreated wood.  相似文献   

15.
This work analyzes the impact of radiata pine (Pinus radiata D. Don) juvenile wood on the physical and mechanical properties of oriented strandboards (OSB). Radiata pine logs were obtained from 10 trees of a 26-year old managed stand located in the 8th Region of Chile. The experimental design considered the proportion of juvenile wood and strand orientation as independent variables. OSB panels of 0.4 m×0.4 m×12 mm were produced and tested. The results show that the juvenile wood proportion has a significant impact on the physical and mechanical properties of OSB. Strands orientation had a significant impact on all the properties studied with the exception of the modulus of elasticity in bending. However, this impact was small in all cases and would not change panel grade with the exception of linear expansion. In this case, panels made from tangential strands showed a higher linear expansion. According to these results, radiata pine juvenile wood can be used for the manufacturing of OSB up to a proportion of 70% of the oven-dry wood weight without significant losses of the physical and mechanical properties if the juvenile wood strands are located in the surface layers.  相似文献   

16.
The mechanical behavior of heat-treated spruce wood was investigated in relation to the mass loss that occurs during thermal treatment. At constant wood moisture content, the strength, failure strain and toughness of wood were reduced by the heat-bath treatment, decreasing with increasing mass loss. The stiffness was unaffected up to a mass loss of about 3%, and thereafter it decreased. The mechanical properties, however, are not only dependent on the mass loss but also on the relative humidity in the heating atmosphere. As a function of mass loss, the inelastic ductility and the inelastic toughness were the lowest when wood was heated in a dry climate, as compared to a moist climate. On the other hand, the mechanical properties of heat-treated wood were tested at constant ambient humidity. In such circumstances, the failure strain and the toughness were still reduced, but the strength and the stiffness were actually improved up to a mass loss of about 2%–3%. The improvement is due to the lower equilibrium moisture content of heat-treated wood when placed in service conditions. As a function of mass loss, wood heated at intermediate relative humidity (in the vicinity of 50%) exhibited the best mechanical behavior, which surprisingly included inelastic ductility. This is believed to be due to some irreversible hydrogen bonding.  相似文献   

17.
销售者作为农产品信息链的纽带,对农产品信息的传递有着决定性的影响。本文以144个农产品销售者为研究对象,探讨了其质量安全追溯意愿,发现41.67%的农产品销售者在农产品出现质量问题时有向上一级供应者追溯的意愿。影响农产品销售者追溯意愿的因素有销售规模、销售点已有年限、是否有固定供应者、销售时是否开票、“三证”是否齐全等。  相似文献   

18.
The study for the elaboration and certification of four olive oil reference materials covering all the physical–chemical characteristics, defined in Commission Regulation (EC) 1989/2003, is reported herein. The different steps of the process, preparation of reference materials, homogeneity and stability studies, and characterization study have been carried out for 14 laboratories from five European countries. The certificate of analysis for these certified reference materials (CRMs) provide assigned values for concentrations of more than 50 parameters or characteristics of olive oils in compliance with the European legislation about the labeling of food products. The certified values and its corresponding uncertainties were obtained applying robust statistics to the raw data provided by the laboratories taking part in the interlaboratory study. The certificate is valid for a maximum period of 18 months from the elaboration date. These four CRMs are intended for use as a primary material for quality control and for validation of analytical methods for measurements in authentication and adulteration problems of olive oils.  相似文献   

19.
At present, wood particles (wood flour) with a low aspect ratio are mostly used as fillers in wood-plastic composites (WPC). Reinforcement of WPC and improved strength properties may be achieved by using real wood fibres with a high aspect ratio. WPC based on 70% (wt.) refiner (TMP) wood fibres and mechanically processed hemp fibres were extruded in a two-step process. Eleven compounds based on the two natural fibre types were prepared using a thermokinetic mixer and extruded in a conical, counter-rotating twin-screw extruder. Additional formulation components were polypropylene fibres, maleic anhydride-modified polypropylene (MAPP) and lubricant. It was determined that compounding in a thermokinetic mixer is a useful step for processing of WPC with refiner and hemp fibres as little fibre damage occurred. However, during extrusion, both natural fibre types were severely shortened due to strong shear forces, and homogeneous dispersion of fibres in the matrix was not achieved. WPC based on hemp fibres displayed the best strength properties of the formulations tested. Current extruder screw and die configurations need to be modified to achieve improved fibre reinforcement and to create new, structurally demanding applications for WPC. Using dynamic mechanical analysis, fibre-matrix adhesion of WPC was investigated, and activation energies for glass transition of selected formulations were calculated. Activation energy for formulations containing MAPP was higher than for WPC without MAPP. This indicates that better fibre-matrix adhesion was achieved in formulations with MAPP.  相似文献   

20.
Several physical-mechanical properties of wood are evaluated from specimens in the green condition. Air-dry samples are often simply re-wetted by direct immersion in order to raise the moisture content above the fiber saturation point. It is assumed that this treatment has no effect on the properties of wood and is equivalent to the green condition. The purpose of this study was to evaluate the influence of water re-wetting processes on the dimensional properties in beech wood. Matched samples were subjected to three different full-water saturation treatments ranging from a four step mild procedure to a one-step drastic procedure. Results showed that the re-wetting process had a significant effect on swelling and shrinkage of beech wood.  相似文献   

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