Browse

61 - 70 of 161 items :

  • Business and Economics x
  • Materials Sciences x
  • Materials for Energy x
Clear All
Analysis of Injection Systems Types Used in Agricultural Machines

Abstract

The paper presents analysis of the processes taking place in fuel systems which lead to damage of injection devices in farm machines. The most frequent reasons of failure of traditional injection systems and Common Rail high pressure systems which are caused inter alia by an improper quality of diesel oil were described and discussed. Microscopic tests of the surface of worn plungers of the plunger and barrel assemby of Motorpal injection pumps used in Zetor tractors were carried out. Types of damage to elements of the injection pump and electromagnetic injectors used in Common Rail systems CP4 type based on the tests on the group of 126 on-site repairs were assessed. Repairs were made in the repair centres in Podkarpackie Voivodeship and centres dealing with repair of injection systems. Metallographic tests were carried out in the Laboratory of Materials of Rzeszow University of Technology with the use of electrone scanning microscope Hitachi S-3400N.

Open access
Assessment of Particular Qualities of Carrot Availalbe in Selected Retailers in Krakow

Abstract

The objective of the paper was assessment of the selected qualities of carrot from retailer's shops, organic and traditional food shops in Krakow. The following quality parameters of the fruit pulp were investigated: content of extract, sugars, polyphenols, nitrite, flavonoids, beta-carotene, colour, and antioxidant activity. The investigation shows that the content of nitrogen (V) in the samples of carrot from traditional cultivations was higher than in case of carrot from organic crops, and in case of a sample from traditional cultivation it exceeds the admissible norms. However, the research which was carried out provides no justification for the statement that the content of nitrate (III) depends on the production system of carrot. The research on the content of polyphenols, flavonoids and antioxidant activity of juice proved the increased antioxidant ability of carrot that was traditionally cultivated with reference to carrot cultivated organically. However, the differences were not statistically confirmed. Beta-carotene content in all samples was comparable regardless the cultivation system. Content of extracts, total carbohydrates and sucrose was significantly higher for carrot from traditional crops than for eco-carrot.

Open access
Assessment of Plant Germination Intensity with the Use of Automated System with Computer Vision Method

Abstract

The objective of the paper was to show various options of using by author an automated stand with computer image analysis for control of plant germination on the example of cauliflower Brassica oleracea L. ‘Pionier” variety. The developed system consisted of a mobile platform equipped with the acquisition and image processing system based on Raspberry PL processor. Germination of cauliflower seeds was the object of observation, which in one case were sown to soil after dressing them with plant extracts (sweet flag Acorus calamus L., great burdock roots Arctium lappa L.). In the other case, undressed seeds were sown in the place of previous application of the above-mentioned extracts. The use of a robot for monitoring plant germination enabled the automated analysis of the investigated material with higher frequency than it has been possible so far. Simultaneously, higher germination was reported when seeds were treated with macerates and extracts from great burdock roots.

Open access
Assessment of Sowing Quality of Radish Seeds with Working Unit of Pneumatic Seeder

Abstract

The objective of the research was assessment of the sowing quality of radish seeds with the sowing unit of “MAX PNEUAMTIC” S 156 pneumatic seeder. Tests were carried out on the original laboratory stand. They proved that at the assumed range of the working speed within 2.5 to 4.0 km·h−1 and rotations of the sowing disc between 23 and 37 rot·min−1, the most favourable results concerning precision of seeds spacing in a row were obtained at the speed between 2.5 and 3.0 km·h−1. The increase of the speed above 3.0 km·h−1 caused deterioration of the seeds sowing quality through statistically significant reduction of the single sowing participation and the increase of the empty sowings participation.

Open access
Effects of Glycerol and Diameter of Holes in Breaker Plate on Performance of Screw Mixer for Nanocomposites

Abstract

A breaker plate of a screw mixer is an efficient mixing device for use in homogenizing nanocomposites. This research was undertaken to investigate the effects of glycerol and diameter of holes in a breaker plate on performance of a screw mixer for nanocomposites. Samples of the nanocomposites were formulated by blending 1000 g cassava starch, 45-55% glycerol and 2% magnetite nanoparticles; and used to evaluate the performance of a locally developed screw mixer at 5 mm and 7 mm diameters of holes in its breaker plate. The effects of glycerol and diameter of holes in the breaker plate on mixing index, amount of unmixed nanocomposites and output/1000g were evaluated as performance indices for 1 hour. Empirical models were determined for predicting the performance of the mixer within the designed criteria. The results showed that the output/1000g and the mixing index increased with higher glycerol and diameter of holes in the breaker plate. However, the amount of unmixed nanocomposites decreases with a higher diameter of holes in the breaker plate (p<0.05). The maximum output/1000g and mixing index lies between 5 mm diameter of holes in the breaker plate and 55% glycerol concentration with an approximate desirability of 0.60. The empirical models developed were fit (R2=0.89, p<0.05); and there were no significant differences between actual and predicted values. The results suggest application of 5 mm diameter of holes in the breaker plate for homogenizing nanocomposites for optimum performance.

Open access
Energy Input on Cover Crop Cultivation

Abstract

The research was carried out in 2015-2016 at the Research Station Brody belonging to Poznan University of Life Sciences. The experiment was assumed with blocks randomized in four replications. The aim of the study was to determine the size and structure of energy inputs incurred on cover crops cultivation in different soil tillage systems. The cumulative energy consumption methodology was used to analyse the energy expenditure on field pea and white mustard seed. Based on the research, it was found that sowing field pea as a cover crop as compared to white mustard increased the cumulative energy input by 63.2%. Applied sowing technologies, regardless of cover crop species, reduced cumulative energy use by 22.5% (strip tillage) and direct sowing by 40.7% as compared to traditional tillage. The structure of energy input depended on the type of used cover crop species, which was based on the energy value of the seed used. The value of the energy efficiency index for growing both cover crop species increased with the simplification of the tillage.

Open access
Fuel Consumption and Effectiveness of Elimination of Energy-crop Willow Plantation

Abstract

The objective of the paper was to determine fuel consumption on elimination of the energy willow plantation with current mechanical methods with the use of the machine research model. The paper covers investigations of four machine units. The lowest fuel consumption (142.6 l∙ha−1) with the use of Meri Crusher MJS-2.0) did not ensure effectiveness of operation of this unit. Efficiency of elimination of the plantation in this case is only 36.4%. On the other hand, the highest consumption of diesel oil (776.4 l∙ha−1) was reported for FAO FAR model FV 4088, and the effectiveness of elimination was not satisfactory and it was 57.0%. The highest effectiveness of elimination of the plantation was reported for the model of a new machine. Fuel consumption in this case was 535.7 l∙ha−1 and the willow plantation elimination effectiveness was the highest and it amounted to 94.8%.

Open access
Granulated Coffe Grounds Effect on Selected Physico-chemical and Functional Properties of Soil

Abstract

The study evaluates granulated coffee grounds use as an additive to soil. Specific physico-chemical and functional properties of soil that enable assessment of its fertility and that have a possible impact on plants growth and development were analysed. The research proved that granulated coffee grounds added to soil increase sorption properties and decrease pH of the soil solution. Moreover, the increase of the phenol compounds that decreased the germination ability and reduced the length of roots of a test plant, namely winter wheat, was reported.

Open access
Mathematical Modeling of Actinidia arguta (Kiwiberry) Drying Kinetics

Abstract

Consumers and scientists exhibit a growing interest in bioactive ingredients of natural origin with strong pro-health effects. Such properties have been found in fruits of of Actinidia argute, commonly known as kiwiberry (mini kiwi or hardy kiwi). Appropriate methods and parameters of the drying process enable obtaining a product with preserved high pro-health properties. The obejctive of this paper was to study the influence of the selected drying methods on the drying kinetics of actinidia. Commonly known mathematical models were used to describe the process. The kinetics of convective, microwave-convective, infrared and vacuum drying was investigated. The process was performed until samples reached dimensionless moisture ratio (MR) of 0.02. The quickest method was vacuum drying reaching moisture ratio target after 286 min, and the slowest was convective drying characterized by 1352 min of drying. In general, Midilli et al.’s model was evaluated as the most adequate for description of the moisture transfer in the fruit samples.

Open access
Modelling of the Separation Process of the Potato Stack

Abstract

The most time consuming and the least mechanized process of potato cultivation is its harvesting. Therefore, now, as never before, we have faced a problem concerning the improvement of the existing and construction of new devices for potato harvesting and their provision to the cultivation industry. It requires further development of theoretical, complex and extensive research on the phenomenon of separation of the potato stack, which will enable justification of optimal work modes of the existing separating devices and will be used for the synthesis of basically new, more advanced separators

Open access