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This study aims to investigate the effect of reactor temperature on softwood and hardwood pyrolysis. Experiments are performed at six temperature levels ranging from 300 to 800°C under N₂ atmosphere. The weights of char, tar and gas yields produced were measured and recorded in percentage of initial weight of the pyrolyzed samples. Results of the study showed that hardwood produces maximum char, tar and gas yields of 41.02 per cent at 300°C,44.10 per cent at 300°C and 56.86 per cent at 800°C, respectively, whereas softwood produces maximum yields of 30.10 per cent at 300°C, 28.25 per cent at 300°C and 68.73 per cent at 800°C, respectively. Proximate analysis shows that volatile matter, fixed carbon, ash content and moisture content of hardwood are 74.83, 14.28, 2.81 and 8.08 per cent, respectively, and that of softwood are 79.76, 12.65, 0.98 and 6.61 per cent, respectively. Result of the elemental analysis results shows that the carbon, hydrogen, nitrogen, oxygen and sulphur contents for hardwood are 52.20, 6.45, 0.68, 39.64 and 1.03 per cent, respectively, and that of softwood are 45.95, 4.57, 0.56, 48.13 and 0.79 per cent, respectively. The higher heating value of hardwood and softwood are 21.76 and 16.50 kJ/g respectively. This study shows that char and tar yields decrease with increase pyrolysis temperature, whereas gas yield increases as pyrolysis temperature increases for the wood samples considered. At all temperatures considered in this study, gas yields are higher than tar and char yields for softwood, whereas for hardwood, tar yield decreases with increase in temperature with accompanying increase in gas yield.

Experiments are performed at six temperature levels ranging from 300 to 800°C under N₂ atmosphere.

At all temperatures considered in this study, gas yields are higher than tar and char yields for softwood, whereas for hardwood, tar yield decreases with increase in temperature with accompanying increase in gas yield.

Results of the study showed that hardwood produces maximum char, tar and gas yields of 41.02 per cent at 300°C,44.10 per cent at 300°C and 56.86 per cent at 800°C, respectively, whereas softwood produces maximum yields of 30.10 per cent at 300°C, 28.25 per cent at 300°C and 68.73 per cent at 800°C, respectively.

The purpose of this paper is to examine why firms governed by the same environmental management standards within an industry exhibit contrasting responses, with some adhering to the letter and others achieving the spirit behind the standards.

Using Arena et al. (2010) as an analytical schema to examine the institutional dynamics behind such contrasting responses, the paper analyses archival and interview data relating to firm strategy, control technology and human expertise in two contrasting Australian forestry firms.

The embedding and decoupling of environmental standards with a firm’s environmental management practices is influenced, first, by the extent to which founder directors and senior management integrate environmental responsibility with the underlying business motives and, second, by the use of organisational beliefs and values systems to institutionalise the integrated strategic rationality throughout the firm. Finally, informed by the institutionalised strategic rationality, the participation and expertise of actors across the organisational hierarchy determine the level to which the design and execution of the eco-control technologies move beyond merely monitoring compliance, and act to facilitate continuous improvement, knowledge integration and organisational learning at the operational level.

This paper responds to institutional theorists’ call for a holistic explanation that considers the interactions among several intra-organisational factors to explain the dynamics behind why some firms decouple while others do not, even though the firms exist in the same social and regulatory context.

The purpose of this paper is to investigate the static behavior of different type of butt joints for application in a timber sofa furniture frame. In timber sofa structure, butt joints are commonly used between plywood and hardwood members but they are normally designed without any regard to the effect of grain directions of the wood members on the joint strength. The focus of the paper is to look at the effect of grain directions on the wooden member properties and on the strength of the butt joint in order to understand the failure mode to establish a more durable and effective sofa butt joint than the one normally used by the manufacturers.

Experiment tests are conducted to determine the mechanical properties of joint members, the maximum load‐carrying capacity of the butt joints, and the types of the failure in the joints in relation to different grain orientations under transverse loading conditions. Plywood and hardwood members are used in construction of the joint tests. Four types of butt joints are constructed with different condition of grain orientation, glue, and screw used in the joint members. The specimens are tested by fixing the plywood member and applying a transverse load to the hardwood member to simulate the conditions in the sofa frame.

Result shows that butt joint with vertical grain orientation and joint with two screws and glue have the maximum load‐carrying capacity compared to the other three cases and compared to the current joint type used in the existing sofa frame design.

The paper is of value to furniture manufacturing industry, in which furniture members and joints are usually over‐designed without regard to grain orientations or applying sound engineering techniques.

States that while mature industries are a major part of the US economy, little empirical information is available on competitive strategies appropriate in the mature environment. Discusses, via a case study of the US hardwood lumber industry, the idea that cost‐based strategies based on Overall Cost Leadership are not sufficient for mature basic industries. Concludes that the results offer understanding of the strategic changes which can occur during the maturity stage of the industry life cycle and recommends possible ways of competing in this environment.

Discusses the considerations to be made when specifying timber for building purposes, particularly BS classification and hardwood/softwood use. Considers the main factors in detail: strength, quality, sizes, moisture content, durability and preservation, fire resistance, and species. Concludes that, contrary to popular belief, timber is ecologically benign, and its use should be encouraged.

Cement bonded composites of 1250 kg/m³ were made in the laboratory either as single layer composed of exclusively oil palm empty fruit bunch (EFB); Tropical hardwood sawmill residue (THSR) or randomly mixed particles (40% of EFB and 60% of THSR oven dry wt/wt) OR of 3-layer composed of 1:2:1 ratio (for face layer of THSR; core layer of EFB and back layer of THSR particles, wt/wt, respectively). Composites were produced at 4 levels of CaCl₂ addition (0, 1, 2 and 3% wt/wt based on cement wt) and 6 levels of initial water content of the cement/aggregate mixture (2.5:1:0.5; 2.5:1:1; 2.5:1:1.5; 2.5:1:2; 2.5:1:2.5 and 2.5:1:3; ratio wt/wt based on cement wt plus oven dry wt of particles). Proximate chemical analysis of representative samples reveal hollocellulose content (77.35 and 74.11%); a-cellulose (43.51 and 52.01%); Hemicellulose (22.9 and 20.2%). Lignin (17.8 and 22.5%); Ash (0.91 and 1.85%) and solubility in Alcohol-benzene (1.6 and 3.98%); cold water (2.42 and 3.15%); Hot water (2.93 and 5.06%); and 1% NaOH (23.4 and 26.11%) respectively for EFB and THSR. Also Morphological studies reveal mean fiber length (1.06 and 1.18mm); Fiber diameter (11.75 and 17.40μm), slenderness ratio (55.79 and 35.98) and Rigidity co-efficient (0.38 and 0.47) respectively for EFB and THSR. The above make both particle sources suitable substitutes for virgin fiber/particles from hardwoods. A total of 192 composites were made representing two panels per production mix. Composites were sampled and tested in accordance with provisions of ASTM D1037-2007. Composite properties ranges are MOR (2.61–20.81 MPa); MOE (2180–5764 MPa); IB (0.28–0.75 MPa). WA (16.41–28.11%) and TS (1.26–5.98%). Properties were evaluated and only production mix that met both the requirements of International Organization for Standardization (10S 8335–1987) and Malaysian Standard Institute (MS 934–1984) were recommended. Acceptable composites were produced from production mix of initial water content ≥1.5 or 30% (based on cement wt + oven dry wt of particles, wt/wt) and 2 or 3% CaCl₂ additive in case of single layer composites while ≥ 2 or 36.36% of initial water content is required in 3-layer composite using same additive level. The effects of furnish type and composition, additive level and initial water content on properties were all found significant (P > 0.01) in factorial analysis.

The blades of an airscrew or spars and similar hollow structural parts of aircraft are formed of two shell sections of wood laminæ joined together with a moisture‐resisting adhesive, each shell section forming in the case of a blade substantially one face of the blade and being made by assembling very thin wood laminæ between shaped dies, which dies may be heated as well as pressed together. The wood laminæ is preferable less than one millimetre in thickness and the laminæ may be assembled so that parts which take higher stresses are more highly compressed. The laminæ 9 are treated with a resin and pressed between the dies, 7, 8 which have tubes 10 for conveying a heating medium. After pressing, the parts may be clamped together while the shell member is setting, and finally the free edges 11 are cut away. If desired, the shell‐like members 2, 3 may be strengthened by inner longitudinal ribs 22 and the parts are subsequently united by gluing at the leading and trailing edges. For the purpose of securing the blade root within a cylindrical socket, it may have an inner stiffening tube 15 and an outer hardwood sleeve 17 to which a metal sleeve 16 is attached. Alternatively, the hardwood sleeve and metal sleeve are both placed inside and outer clamping sleeves are employed. The shell members 2, 3 may be enclosed in a metal sheeting 23, 24, the edges of which are joined by welding or by interlocking the edges 25. The leading edge may be formed by a separate member 30 dovetailed as at 34 into the outer shells, and such member may be formed with a rubber tip 37 or be wholly of rubber. The resistance to bending stresses may be increased by loading the blade tip either by adding weight or using material of high density. The wood laminæ may be interleaved with laminæ of other suitable pliable material such as fabric or metal gauze.

This is a real case involving an SME that produces southern hardwood finished lumber. The family business faces a social responsibility dilemma in terms of displaced workers and limited job opportunities in the surrounding labor market if they purchase a new saw that would modernize production, improve profitability, and eliminate 50 percent of their labor costs.The most logical employment for these workers would be a cutter, loader, or hauler of logs, which have been determined to be some of the most dangerous jobs in the United States. This case requires students to examine the decision-making process of a modest family business in a small, cohesive community and the ramifications of these decisions, as well as issues concerning technology and production improvements, displaced workers, social responsibilities, and the rights and responsibilities of employers and employees.

This paper seeks to frame and model the environmental issues and impacts associated with the management of pallets throughout the entire life cycle, from materials to manufacturing, use, transportation to end‐of‐life disposal.

A linear minimum cost multi‐commodity network flow problem is developed to make pallet‐related decisions based on both environmental and economic considerations.

This paper presents a review of the environmental impacts associated with pallets by life cycle stage. The types of materials used to fabricate pallets, the methods by which they are treated for specific applications, and various pallet management models are described with respect to embodied energies, toxicity and emissions. The need for companies to understand the cost, durability, and environmental impact tradeoffs presented by pallet choices is highlighted. The paper introduces a model to assist in choosing both how pallets are managed and the material they are constructed of that balances these tradeoffs.

There is limited research on the environmental impact of different management approaches of large‐scale pallet operations. The proposed model and approach will provide companies seeking to engage in more sustainable practices in their supply chains and distribution with insights and a decision‐making tool not previously available.

The MATEX 2000 scientific kit, of Swiss origin, is now available in the UK. Over 5 000 kits of this type are already being used by schools in some forty different countries. All the 210 items of equipment (see picture, right, and key on following page) are stored in a transportable hardwood cabinet with metal handles — approximate dimensions are 33in by 26½in by 10½in; approximate weight 110 lb. An illustrated ring‐back guide, provided with each kit, describes over 600 basic experiments in physics, chemistry and biology. These are above ‘O’‐level standard, but in some cases may not be sufficient for ‘A’‐level, though naturally the equipment itself could be used for experiments at any level.