Tag Archives: concentration

183-192 M. Pourebrahimi Foumani, H. Savoy, N. Atotey and X. Yin
Effect of potassium application rate and timing on alfalfa yield and potassium concentration and removal in Tennessee
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Effect of potassium application rate and timing on alfalfa yield and potassium concentration and removal in Tennessee

M. Pourebrahimi Foumani¹, H. Savoy², N. Atotey³ and X. Yin¹*

¹University of Tennessee, Department of Plant Sciences, West Tennessee Research and Education Centre, 605 Airways Blvd., Jackson, TN 38301-320, USA
²University of Tennessee, Department of Biosystems Engineering and Soil Science, 2506 E J. Chapman Dr, Knoxville, TN 37996, USA
³University of Tennessee, Department of Biosystems Engineering and Soil Science, West Tennessee Research and Education Centre, 605 Airways Blvd., Jackson, TN 38301-320, USA
*Correspondence: xyin2@utk.edu

Abstract:

Alfalfa (Medicago sativa L.) is the most important forage crop in the world and potassium plays a significant role in achieving high yields. A field experiment was conducted during the 2012–2014 growing seasons at the University of Tennessee in Springfield. The experimental design was a split-split plot that included four levels of potassium (K) application rates (0, 67.25, 134.50, and 269.00 kg K2O ha-1) as the main plots and two K application times (green-up and split) as the subplots, and harvest dates as sub-subplots. The results demonstrated that the dry matter yield (DM) increased significantly with each increment in K application rate up to 134.50 kg K2O ha-1; however, the highest K fertilizer application (269 kg K2O ha-1) did not result in a significant yield increase relative to 134.50 kg K2O ha-1, because some luxury consumption of K occurred at the highest rate due to yield leveling off while K2O uptake continued to rise. Potassium concentration and K removal increased with K fertilizer at rates beyond those that maximized yield, indicating luxury consumption of K. The greatest K concentration and removal were recorded at 269 kg K2O ha-1 in all harvest months. The split application was more beneficial than applying full K at the time of green-up due to higher dry matter, K concentration, and K removal in alfalfa. In conclusion, 134.50 kg K2O ha-1 is adequate for maximizing alfalfa yield; split application of K is sometimes superior to the single dose of K fertilizer in alfalfa production.

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297–302 K. Veselá, M. Pexa and J. Pavlů
The water content in the engine oil by using E85
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The water content in the engine oil by using E85

K. Veselá*, M. Pexa and J. Pavlů

Czech University of Life Sciences Prague, Faculty of Engineering, Department for
Quality and Dependability of Machines, Kamycka 129, CZ 16521, Prague 6,
Czech Republic
*Correspondence: katerina86@email.cz

Abstract:

The European Union adopted a decision to achieve by 2020 at least 20% reduction in greenhouse gas emissions. To fulfill this task, the EU proposed in 2020 binding targets – further improve energy efficiency by 20%, achieving a 20% share of renewable energy and a 10% share of biofuels in the fuel market. One of the most widely used biofuel in the automotive industry is bioethanol. Bioethanol can be used on low-percentage blending into petrol, which is governed by European Directive 2003/30/EC, and on high-blend bioethanol mixture, particularly E85 consists of 85% bioethanol and 15% petrol BA95. But in recent years, increasingly demonstrating opinions, that biofuels do not produce nearly as much effect as was propagated. This paper deals with the concentration of water in the engine oil with using biofuel E85. The water in the engineoil significantly affects its parameters (especially viscosity). How measurement results demonstrated the use of bioethanol in the fuel increases the concentration of water in the engine oil.

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1152-1159 E. Viirlaid, R. Riiberg, U. Mäeorg and T. Rinken
Glyphosate attachment on aminoactivated carriers for sample stabilization and concentration
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Glyphosate attachment on aminoactivated carriers for sample stabilization and concentration

E. Viirlaid*, R. Riiberg, U. Mäeorg and T. Rinken

University of Tartu, Institute of Chemistry, Ravila 14A, 50411, Tartu, Estonia *Correspondence: edith.viirlaid@ut.ee

Abstract:

Glyphosate (N-phosphonomethylglycine) is the most widely used non-selective postemergence herbicide for weed and vegetation control. The need for monitoring glyphosate levels in environmental samples and agricultural products proceeds from its extensive use due to the unregulated application and contradictory information about its toxicity on living organisms. In order to achieve high sensitivity and reliability of glyphosate assessment, stabilization and preconcentration steps are generally required for its determination in different samples. The aim of the present study was to develop and optimize possibilities for effective glyphosate stabilization and concentration using aminoactivated nano- and microparticles of different materials. The results show that the usage of aminoactivated iron (II,III) oxide magnetic nanoparticles for the attachment and concentration of glyphosate is a prospective option to be integrated with in situ analytical technologies (e.g. biosensors), as the whole processes of glyphosate attachment was efficiently and reproductively carried out within 20 minutes.

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109-114 J. Krupička, P. Šařec and P. Novák
Measurement of electrical conductivity of DAP fertilizer
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Measurement of electrical conductivity of DAP fertilizer

J. Krupička*, P. Šařec and P. Novák

Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, 16521 Prague 6 – Suchdol, Czech Republic; *Correspondence: krup@tf.czu.cz

Abstract:

Paper deals with the measurement of electrical conductivity of significant size groups of mineral fertilizer DAP divided in the air stream. Samples of these groups were dissolved in distilled water and the values of electrical conductivity recorded. Measurements will be used to monitor the electrical conductivity of other mineral fertilizers and to create a standard for qualitative assessment of fertilizer solutions.

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207-214 M. Dubeňová, T. Šima, R. Gálik, Š. Mihina, G. Vagač and Š. Boďo
Reduction of nitrous oxide and carbon dioxide in the pig barn piggery by different ventilation system intensities
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Reduction of nitrous oxide and carbon dioxide in the pig barn piggery by different ventilation system intensities

M. Dubeňová¹, T. Šima²⋅*, R. Gálik¹, Š. Mihina¹, G. Vagač³ and Š. Boďo¹

¹Slovak University of Agriculture in Nitra, Faculty of Engineering, Department of Production Engineering, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic 2Slovak University of Agriculture in Nitra, Faculty of Engineering, Department of Machines and Production Systems, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic; *Correspondence: tomasko.sima@gmail.com 3Slovak University of Agriculture in Nitra, Faculty of Agrobiology and Food Resources, Department of Animal Husbandry, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic

Abstract:

Agriculture, especially animal production, is one of the most important factors influencing greenhouse gases in the atmosphere and causing global warming. The ventilation system in a piggery has a significant impact to carbon dioxide (CO2) and nitrous oxide (N2O) concentrations. The concentrations of these gases in pig housing also affect the air quality and welfare of animals. The aim of the paper was to analyze the effect of ventilation system intensity on the concentration of CO2 and N2O in a piggery. An experiment was carried out at the Experimental Centre for Livestock at the Department of Animal Husbandry, Faculty of Agrobiology and Food Resources, the Slovak University of Agriculture in Nitra, Slovakia. The concentrations were measured by a photoacoustic field gas monitor INNOVA 1412 connected to a multipoint sampler INNOVA 1309. Three levels of ventilation system intensity were used: low, medium and high. Fattening pigs, the Large White breed were housed in the piggery. For our experiment, three sensors were used inside and two sensors outside the barn. Based on the gathered data, statistically significant differences were found between different ventilation system intensities at a 95.0% confidence level. The concentration of gases fluctuates during day time interval and, based on the results, it is possible to set up a ventilation system intensity to create the best possible air quality in a building for pigs.

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