Research in Agricultural Engineering, 2016 (vol. 62), issue 4
INDEX OF VOLUME 62
editors
Res. Agr. Eng., 2016, 62(4):X1 | DOI: 10.17221/9359-RAE 
Yield and fuel characteristics of willows tested for biomass production on agricultural soilOriginal Paper
J. Weger, P. Hutla, J. Bubeník
Res. Agr. Eng., 2016, 62(4):155-161 | DOI: 10.17221/12/2014-RAE
Short rotation coppice (SRC) plantations of fast growing trees in Czech Republic may be grown on approximately 120,000 ha in future, as indicated in the Czech Action Plan for Biomass. Until now, 2,800 ha of SRC were established using predominantly poplar non-native hybrid clone Max-4. The aim of this experiment and article is evaluation of promising domestic clones of willow species and their natural hybrids, to discover their yield parameters and fuel characteristics in field conditions. The experiment was established in Průhonice in 2005 and it was harvested two times in triennial rotation (2008, 2011). For the test of fuel properties biomass was...
Effect of moisture content on some physical properties of Canarium schweinfurthii Engl. fruitsOriginal Paper
J.C. Ehiem, V.I.O. Ndirika, U.N. Onwuka
Res. Agr. Eng., 2016, 62(4):162-169 | DOI: 10.17221/11/2015-RAE
The effect of moisture content on some physical properties of three varieties of Canarium schweinfurthii Engl. fruits (small, large and long) was studied at 40.91%, 34.92%, 23.44%, 18.5% and 11.03% moisture content on wet basis in order to solve problems associated with designing and development of processing and handling equipment for these fruits. The physical parameters investigated were major, intermediate, minor diameters, geometric mean diameter, unit mass, volume, sphericity, density, bulk density, roundness, aspect ratio, porosity, surface and specific surface area. The results obtained showed that the physical parameters decreased...
Drying characteristics of eggplant (Solanum melongena L.) slices under microwave-convective dryingOriginal Paper
R.A. Chayjan, M. Kaveh
Res. Agr. Eng., 2016, 62(4):170-178 | DOI: 10.17221/13/2015-RAE
A laboratory scale microwave-convection dryer was used to dry the eggplant fruit, applying microwave power in the range of 270-630 W, air temperature in the range of 40-70°C and air velocity in the range of 0.5-1.7 m/s. Six mathematical models were used to predict the moisture ratio of eggplant fruit slices in thin layer drying. The results showed that the Midilli et al. model had supremacy in prediction of turnip slice drying behavior. Minimum and maximum values of effective moisture diffusivity (Deff) were 1.52 × 10-9 and 3.39 × 10-9 m2/s, respectively. Activation energy values of eggplant slices...
Mass yield of biochar from hydrothermal carbonization of sucroseOriginal Paper
J. Velebil, J. Malaťák, J. Bradna
Res. Agr. Eng., 2016, 62(4):179-184 | DOI: 10.17221/73/2015-RAE
In this article, the effect of increasing dry matter content and reaction time of hydrothermal carbonization on mass yield of biochar was studied. Carbonization took place in batch experiments in a pressure vessel. Results have confirmed the assumption that the mass yield of biochar would increase with growing dry matter content in the initial solution and also with reaction time at reaction temperature of 200°C. It was found that components of the liquid product that remain in the biochar have a measurable impact on its mass yield. Mixing of the reactor proved to have a considerable effect on the mass yield as well. Biochar produced in absence of...
Frequency analysis of noise exposure of dairy cows in the process of milkingOriginal Paper
M. Pšenka, M. Šístková, Š. Mihina, R. Gálik
Res. Agr. Eng., 2016, 62(4):185-189 | DOI: 10.17221/4/2015-RAE
In the environment of farms and farm buildings, cattle are exposed to various unnatural influences. Such an impact is also noise always arising with a certain energy conversion. In cattle farms, the sources of noise are represented by various mechanical equipment and machines that are used for enabling farm operations. The aim of the paper was to analyse the noise levels in dairy cattle production in the environment, during their day routine. Noise levels were measured at two farms with a different technological layout of milking parlour, with a different way of milking. The noise exposure of dairy cows was measured in three locations, namely in the...
Some causes of differences in the NH3 concentration measured with the semiconductor sensors by one manufacturerOriginal Paper
P. Zabloudilová, J. Pecen, M. Češpiva
Res. Agr. Eng., 2016, 62(4):190-197 | DOI: 10.17221/80/2015-RAE
The paper deals with continuous monitoring of NH3 desorption from material used as bedding in animal breeding establishments, using five semiconductor sensors SP-53 (FIS Inc.). In lab experiments, two groups of sensors from two categories, to which the manufacturer divided the sensors based on the value of their resistance RS, were used. Also the influence of air humidity over the values of NH3 concentrations measured by individual sensors was monitored. The study ascertained statistically relevant differences between NH3 concentration values measured by both groups of sensors, in the range from...
Bonding of plywoodOriginal Paper
M. Brožek
Res. Agr. Eng., 2016, 62(4):198-204 | DOI: 10.17221/39/2015-RAE
The contribution contains results of bonded joints strength tests. The tests were carried out according to the modified standard ČSN EN 1465 (66 8510):2009. The spruce three-ply wood of 4 mm thickness was used for bonding according to ČSN EN 636 (49 2419):2013. The test samples of 100 × 25 mm size were cut out from a semi-product of 2,440 × 1,220 mm size in the direction of its longer side (angle 0°), in the oblique direction (angle 45°) and in the direction of its shorter side (crosswise - angle 90°). The bonding was carried out using eight different domestic as well as foreign adhesives according to the technology prescribed by the producer. All...