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101.
The main objective of this research was to study the potential of waste agricultural residues such as sunflower stalk, corn stalk and bagasse fibers as reinforcement for thermoplastics as an alternative to wood fibers. The effects of two grades (Eastman G-3003 and G-3216) of coupling agents on the mechanical properties were also studied. In the sample preparation, one level of fiber loading (30 wt.%) and three levels of coupling agent content (0, 1.5 and 2.5 wt.%) were used. For overall trend, with addition of both grades of the coupling agents, tensile, flexural and impact properties of the composites significantly improved, as compared with untreated samples. In addition, morphological study revealed that the positive effect of coupling agent on interfacial bonding. The composites treated with G-3216 gave better results in comparison with G-3003. This could be caused by the high melt viscosity of G-3003. In general, bagasse fiber showed superior mechanical properties due to its chemical characteristics.  相似文献   
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The RAMseS project, financed by the European Commission under the 6th framework Program, has the purpose of developing a solar powered agricultural vehicle in order to replace the conventional vehicles based on internal combustion engines (ICE). In the present study, we report a comparison of life-cycle emission between two systems; a conventional ICE vehicle (ICEV) and the RAMseS electrical vehicle (EV). The study has been conducted by designing a specific model and using the SimaPro software. The results show that the RAMseS system is considerably more environmentally friendly than conventional ICE based system and that, specifically, it can avoid the emission of about 23 ton of CO2equ per year. Regarding all other pollutants, we found that the RAMseS system is 2.6 times more efficient than the ICEV. The main contribution to emissions of the RAMseS system is due to the batteries which contribute for a 73% of the total. Therefore, further improvement can be obtained with the use of more advanced battery systems, not based on lead.  相似文献   
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This study investigates the impact of radiation heat transfer and heat conduction on dust cloud combustion. Radiation plays a very important role in the stability of dust cloud flame, and increasing the amount of radiation drastically raises the possibility of instability and explosion in a dust cloud mixture. Flame speed, which is a function of mixture characteristics, can exhibit a fluctuating behavior. By using the discrete heat source method, it would be possible to study the transient propagation of dust flames. Thus, the propagation speed of flame can be obtained, and as time goes by, the transient speed of dust flame will reach its steady state value. By considering the radiation effect, better agreement is observed between the obtained results and experimental data.  相似文献   
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Environment, Development and Sustainability - The large-scale water-induced erosion is one of the most determining elements on land degradation in subtropical monsoon-dominated region. From this...  相似文献   
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Objectives. Musculoskeletal disorders (MSDs) are prevalent among airline baggage handlers due to manual materials handling. In this study, the Nordic musculoskeletal questionnaire (NMQ), the revised National Institute for Occupational Safety and Health (NIOSH) lifting equation, and the University of Michigan 3D Static Strength Prediction Program? (3DSSPP) were used to analyze MSDs among baggage handlers. Methods. The NMQ was filled out by 209 baggage handlers and 46 arbitrarily selected baggage handlers were evaluated using the NIOSH method and 3DSSPP. Results. The obtained results showed that the most common MSDs occurred in the lower back region. The next risky regions included knees, neck, and upper back, respectively. The NIOSH results confirmed that the subjects lifted loads heavier than the permitted limit and their lifting postures were inappropriate. The results of the 3DSSPP also indicated that compression forces exceeded the NIOSH limit in these awkward postures. Conclusions. Relying on this study, holding compulsory ergonomic lifting training courses could be proposed for workers and regulations adjusting an upper limit for maximum baggage weight must be also enacted in order to improve occupational health and prevent the prevalence of increasing MSDs.  相似文献   
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