Research in Agricultural Engineering, 2004 (vol. 50), issue 2

Research of biological agents effects on reduction of ammonia concentration in stables of intensive farm animals breeding

A. Jelínek, M. Dědina, P. Plíva, J. Souček

Res. Agr. Eng., 2004, 50(2):43-53 | DOI: 10.17221/4926-RAE  

In the study are presented results of experiments using bio-technological agents Amalgerol, Bio-Algeen G-40 and Biostrong 510 in intensive pig, poultry breeding and cattle slurry treatment for ammonia emissions reduction. The measuring was conducted, suggested and verified by continual method through the measuring station ASECO and instrument 1312 Photoacoustic Multi-gas Monitor of firm INNOVA Air Tech Instruments. The reached results confirm unambiguously possibility to reduce ammonia emissions from farm animals breeding.

Static and dynamic tests of pear bruise sensitivity

J. Blahovec, V. Mareš, F. Paprštein

Res. Agr. Eng., 2004, 50(2):54-60 | DOI: 10.17221/4927-RAE  

The paper is a continuation of the preceding research of bruising sensitivity applied to different pear varieties. This study was based on quasi-static fruit testing in compression between two plates. One part of the method is based on determining the hysteresis losses corresponding to the predetermined low level bruising. This paper contains an attempt to apply the hysteresis loss concept to dynamical impact tests, which are simpler and quicker then quasi-static ones. Moreover the impact tests are closer to the character of deformations that initiating the bruising process in real conditions. Nine pear varieties were tested quasi-statically by the...

Change in humidity of solid biofuels

P. Heneman

Res. Agr. Eng., 2004, 50(2):61-65 | DOI: 10.17221/4928-RAE  

Humidity, as one of the most important physical properties of pressed solid biofuels, affects thel calorific value of the biofuel and its consistency. Biofuel humidity depends on the initial humidity of raw material, which varies and depends on many factors. Method of manufacture and place and duration of storage have a considerable effect on solid biofuel humidity as well. Humidity of pressed solid biofuels changes not only during the pressing itself, when temperature increases by compression and a part of contained moisture evaporates, but also in the course of handling and storage under unstable environment conditions with high relative air humidity,...

The effect of working conditions on the selected parameters of duckfoot shares

M. Fríd, J. Šabatka, I. Celjak

Res. Agr. Eng., 2004, 50(2):66-74 | DOI: 10.17221/4929-RAE  

We measured a series of six duckfoot shares in the years 1999-2000. The purpose of the research project resulted from the Grant EP7111 and the Research project MSM J06/98:122200002/I. We described forces affecting machine implements and we consequently calculated measuring resistances during the ploughing. The deeper the subterranean the higher the linear growth of forces. If the subterranean rises from eight to ten centimetres, it will appear an increase in forces of 59.61 in the horizontal plane and of 30.84 in the vertical plane. If the driving speed increases from 5.91 km/h to 11.38 km/h, i.e. 1.64 m/s to 3.16 m/s, the forces will...

Application of ductile iron in the manufacture of ploughshares

R. Březina, J. Filípek, J. Šenberger

Res. Agr. Eng., 2004, 50(2):75-80 | DOI: 10.17221/4930-RAE  

The service life and reliability of machines for basic soil cultivation is mainly affected by abrasive wear. The working tools of these machines are mostly made of steel. The paper deals with the possibility of manufacturing ploughshares and reversible points of austempered ductile iron (ADI). The authors examine the abrasion resistance of ADI working tools and compare it with that of the material applied by a leading world manufacturer of ploughshares. Using an appropriate mode of the heat treatment of ADI, abrasion resistance comparable to that of the original tools can be obtained.

External factors and their impact on the metabolism and technological quality of stored sugar beet

R. Rybář

Res. Agr. Eng., 2004, 50(2):81-87 | DOI: 10.17221/4931-RAE  

Technological quality of sugar beet is a complex of biological, chemical, physico-chemical and mechanical properties of the sugar beet root, which are conclusive to decide upon a proper warehousing and subsequent processing of the crop aimed at reaching a maximum yield of white refined sugar (raffinade). It is affected by a number of external and internal factors of the field during the growing season and during the post-harvest storage. This particularly applies to sugar beet meant for sugar factory processing in the months of November and December, i.e. to about 40-60% of total sugar beet crop harvested in the Czech Republic. Having been lifted at...