Template-Type: ReDIF-Article 1.0 Author-Name: editors Title: LIST OF REVIEWERS 2012 Journal: Research in Agricultural Engineering Pages: I Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/6677-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/6677-RAE.html File-Format: text/html Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:6677-RAE Template-Type: ReDIF-Article 1.0 Author-Name: T. Dlabaja Author-Workplace-Name: Department of Technological Equipment of Buildings, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: J. Malaťák Author-Workplace-Name: Department of Technological Equipment of Buildings, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Optimization of anaerobic fermentation of kitchen waste Abstract: Anaerobic fermentation is a suitable method of energetic and material utilisation of waste coming from restaurants and canteens. Laboratory experiments of wet anaerobic fermentation were performed in a continuous reactor and in batch reactors under mesophilic conditions. Effects of hydraulic retention time, organic loading rate, period of feeding and recirculation of digestate were examined in the continuous reactor. Effects of substrate pre-treatment (crushing, heating, freezing) were examined in the batch reactors. Degree of substrate degradation ranged between 83-85% within hydraulic retention time of 2-30 days. Appropriate organic loading rate was found in the range 2-3 kg of volatile solids per m3/day. Recirculation of digestate (both an inoculum for fresh substrate and replacement of fresh water supply) caused an increase in ammonia concentration and led to immediate inhibition of the process. The results further showed a positive effect of substrate pre-treatment in the initial phase of fermentation. However, degree of degradation did not show a significant increase for the period of 20 days of fermentation. Keywords: biogas, methane, digestion, waste treatment, biowaste Journal: Research in Agricultural Engineering Pages: 1-8 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/2/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/2/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0002.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:2-2012-RAE Template-Type: ReDIF-Article 1.0 Author-Name: D. Herák Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: A. Kabutey Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: M. Divišová Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Analysis of tangential curve equation describing mechanical behaviour of rapeseeds (Brassica napus L.) mixture under compression loading Abstract: The analysis of tangential curve equation for describing mechanical behaviour of rapeseeds (Brassica napus L.) mixture under compression loading were discussed. Parameters considered in this study include both measured and theoretical amounts of deformation, volume compression and deformation energy. The measured amounts denoted as true defor­mation, true volume compression and true deformation energy were determined directly from the compression test of the rapeseeds pressed mixture whiles the theoretical amounts expressed as max. deformation, max. volume compres­sion and max. deformation energy were determined by mathematical adjustment of the general tangent curve equation which were verified from the measured data. Also the theoretical amounts further explain the limit deformation, limit volume compression and relationship between strains and limit volume compressions which were statistically analysed to describe true situation of pressing. The results indicate that the tangent curve equation by mathematical modifica­tion can be used to determine accurately theoretical amounts of maximal deformation, maximal volume compression and maximal deformation energy. Keywords: force, deformation, oil bearing crops, mathematical model, compression, volume, energy, limit Journal: Research in Agricultural Engineering Pages: 9-15 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/73/2011-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/73/2011-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0003.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:73-2011-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Müller Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: P. Hrabě Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Overlay materials used for increasing lifetime of machine parts working under conditions of intensive abrasion Abstract: We evaluated a degree of the machine part abrasive wear with secondary focus on their hardness. The paper states laboratory results of overlay systems from their wear resistance point of view. Laboratory experiments were carried out by two-body abrasion on bonded abrasive of a P120 granularity. The results proved an increased abrasive wear resistance of martensitic, ledeburitic and stellitic overlays against eleven different original products. The overlay UTP Ledurit 60 reached the optimum values. The GD-OES (Glow Discharge Optical Emission Spectroscopy) method proved the different chemical composition of the overlay from the stated chemical composition of the overlaying electrode. Keywords: agriculture, chemical analysis, resistance, two-body abrasion, wear Journal: Research in Agricultural Engineering Pages: 16-22 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/64/2011-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/64/2011-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0004.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:64-2011-RAE Template-Type: ReDIF-Article 1.0 Author-Name: R. Chotěborský Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Effect of heat treatment on the microstructure, hardness and abrasive wear resistance of high chromium hardfacing Abstract: The effect of destabilization heat treatment on the microstructure, hardness, fracture toughness and abrasive wear resistance of high chromium hardfacing was investigated. The results from the study shows that the hardness, frac­ture toughness and abrasive wear resistance are influenced by temperature of destabilization heat treatment and air and furnace cooling conditions, respectively. Destabilization treatment of materials by furnace cooling caused higher secondary carbides in the dendritic austenite whilst by air cooling it showed smaller particles of secondary carbide. Also, it was found that destabilization temperature at 1,000°C improves hardness compared with hardfacing after weld depositing. The study, however, indicated that Palmqvist fracture toughness method is a useful technique for measuring the fracture toughness of high chromium hardfacing compared to Vicker's hardness method. Keywords: destabilized austenite, carbide, dry rubber wheel test, factorial regression, GMAW (Gas Metal Arc Welding), toughness Journal: Research in Agricultural Engineering Pages: 23-28 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/62/2011-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/62/2011-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0005.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:62-2011-RAE Template-Type: ReDIF-Article 1.0 Author-Name: J. Mikleš Author-Workplace-Name: Department of Forest and Mobile Technologies, Faculty of Environmental and Manufacturing Technologies, Technical University in Zvolen, Slovak Republic Title: Research into the geometry of the delimbing head of cutting knives Abstract: Limbing with a wedge tool as a chipless operation is accompanied by a large deformation of wood in the cutting plane, i.e. at the spot of contact with the tool face as well as in the zone adjacent to this plane. The theory of chipless cutting says that the resistance of wood fibers to deformation is particularly the main component of resistance to the tool penetration into wood. The friction component (resistance component) on the tool surface is a function describing resistance to fibre deformation, its magnitude depending upon the value of friction coefficient. The magnitude of cutting force acting in a direction of the velocity vector is a resultant of all resistance components acting on the particular parts of the tool which make up the cutting profile (face, back edge, cutting edge). In the presented paper force analysis is presented for the operation of a delimber. The objective of these experimental tests was to minimize energy requirement for limbing through determination of optimum geometry of delimbers while providing for the good quality of the limbing. Keywords: forest machinery, delimber, delimbing tool, tool geometry Journal: Research in Agricultural Engineering Pages: 29-34 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/50/2011-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/50/2011-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0006.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:50-2011-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Z. Tjiparuro Author-Workplace-Name: Rural Industries Promotions Company Botswana, Kanye, Botswana Title: Challenges of designing a cracker for Morama bean - Short communication Abstract: Experiments were done on Morama beans (Tylosema esculentum) using macadamia nut crackers. Results and subsequent design work done thereafter showed that the cracking of the beans, their alignment during cracking and separation of kernels from shells presented peculiar challenges unresolvable by conventional processes. Keywords: Tylosema esculentum, gemsbok bean, separation methods, agricultural machines Journal: Research in Agricultural Engineering Pages: 35-37 Volume: 59 Issue: 1 Year: 2013 DOI: 10.17221/68/2011-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/68/2011-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201301-0007.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:1:id:68-2011-RAE