Volume 13 (2015)
  Number 5

Full text of the journal: Volume 13 Number 5

Contents

Pages
1165-1192 V. Bulgakov, V. Adamchuk, M. Arak and J. Olt
Theory of vibration-assisted sugar beet root lifting
Abstract |
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Theory of vibration-assisted sugar beet root lifting

V. Bulgakov¹, V. Adamchuk², M. Arak³ and J. Olt³⋅*

¹National University of Life and Environmental Sciences of Ukraine 15, Heroyiv Oborony Str., UK03041 Kyiv, Ukraine
²National Scientific Centre, Institute for Agricultural Engineering and Electrification, 11, Vokzalna Str., Glevaкha-1, Vasylkiv District, Kiev Region, UK08631, Ukraine
³Estonian University of Life Sciences, Institute of Technology, 56 Kreutzwaldi Str., EE51014 Tartu, Estonia;
*Correspondence: jyri.olt@emu.ee

Abstract:

The vibration-assisted lifting of sugar beet roots from the soil has been gaining increasingly wide use worldwide and the majority of sugar beet harvesting machinery manufacturers produce beet harvesters equipped with just such kind of lifting units. In such units the priorities are low tractive resistance, the high quality of harvesting in terms of undamaged side surfaces of beet root bodies and intact tail parts as well as the high degree of their initial cleaning from the stuck soil. However, the parameters of the oscillatory processes generated by the vibrational lifting units used on the majority of sugar beet harvesting machinery in the market have rather average values appropriate for relatively favourable harvesting conditions (soft loose soil, beet root sizes close to the average, properly lined up planting rows etc.). But when the harvesting conditions deviate from their favourable values (especially in case of dry and strong soil), the vibrating lifters start performing the digging process with significant damage to the beet roots (breaking and tearing off the tail parts), their power consumption rises excessively sharply, the unit vibration drives prove to be unreliable. The literature source analysis has shown that any sufficiently detailed, comprehensive and dependable theory of direct beet root lifting from the soil is virtually absent. Thus, the aim of this research study has been to work out such a theoretical basis for the process of vibration-assisted beet root lifting, which will allow to calculate, in accordance with the harvesting parameters, the optimal design and kinematic parameters of the process ensuring the high quality of harvesting. A new theory has been developed, which describes the process of direct vibration-assisted beet root lifting performed under the effect of the vertical disturbing force and the pulling force, imparted to the root by the lifting unit. The obtained system of differential equations has made it possible to establish the law of motion of the beet root in the process of its direct vibration-assisted lifting and perform PC-based numerical calculations, which provide the basis for determining optimal kinematic modes of operation and design parameters of vibrational lifting units subject to the condition of maintaining sugar beet roots intact when harvesting them.

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1193-1201 V. Eremeev, B. Tein, P. Lääniste, E. Mäeorg and J. Kuht
The effect of pre-planting thermal treatment of seed tubers on the yield and quality of potato
Abstract |
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The effect of pre-planting thermal treatment of seed tubers on the yield and quality of potato

V. Eremeev*, B. Tein, P. Lääniste, E. Mäeorg and J. Kuht

Estonian University of Life Sciences, Kreutzwaldi 1, EE51014 Tartu, Estonia *Correspondence: vyacheslav.eremeev@emu.ee

Abstract:

Field trials with the potato cultivars ‘Ants’ (medium late) and ‘Laura’ (medium early) were carried out on the experimental fields of the Department of Field Crops and Grassland Husbandry located at Eerika (58°22′ N, 26°40′ E), Estonian University of Life Sciences in 2010 and 2011. The yield of tubers and starch, marketable yield of potato, number of tubers per plant and tuber weight were studied. We used the following treatments: untreated control (To): seed tubers were planted directly from storage house (storage temperature 4°C); thermal shock (TS): seed tubers were kept before planting 5 days in a room with temperature of 30°C and 2 days with temperature of 12°C; pre-sprouting (PS): before planting the seed tubers were kept 26 days in a room with temperature of 15°C and 10 days with temperature of 12°C. The results are presented as the averages of studied years. According to the average results of two experimental years, the pre-planting treatment with thermal shock increased the number of tubers per plant of cultivar ‘Ants’ by 30.6%, compared to control treatment. None of the treatments had any effect on the number of tubers of cultivar ‘Laura’. The thermal treatment increased the average weight of tubers of cultivar ‘Laura’ compared to the control treatment (thermal shock by 14.7%, pre-sprouting by 20.7%), but for cultivar ‘Ants’ the weight of tubers was decreased by 16.7% (thermal shock treatment). The thermal shock treatment increased the tuber yield of cultivar ‘Ants’ by 10.7% and the pre-sprouting increased the total tuber yield of cultivar ‘Laura’ by 9.9%. The thermal shock increased significantly the starch content of cultivar ‘Ants’ and decreased that of cultivar ‘Laura’.

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1202-1214 M. Golabadi, P. Golkar and B. Bahari
Remobilization assay of dry matter from different shoot organs under drought stress in wheat (Triticum aestivum L.)
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Remobilization assay of dry matter from different shoot organs under drought stress in wheat (Triticum aestivum L.)

M. Golabadi¹*, P. Golkar² and B. Bahari¹

¹Department of Agronomy and Plant Breeding, Collage of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, P.O. Box: 81595-158 Isfahan, Iran
²Institute of Biotechnology and Bioengineering, Isfahan University of Technology, P.O. Box: 84156-2781 Isfahan, Iran
*Correspondence: m.golabadi@khuisf.ac.ir

Abstract:

Remobilization of dry matter during the grain filling period in wheat is capable of helping the plant recover its grain yield under drought stress. In this study, the genotypic variation of different traits related to dry matter remobilization were measured in seven genotypes of wheat under the three different environment conditions of well-watered, drought stress at heading stage with application of extra nitrogen fertilizer (30%), and drought stress in Isfahan, Iran. Analysis of variance showed that the genotypes were different not only in their dry matter remobilization from the spike, the stem, the peduncle, and the leaf sheath but also in their current photosynthesis. Different environmental conditions were found to affect dry matter remobilization from the leaves and sheath, current photosynthesis, grain yield, and the relative contributions by the stem and the spike to grain yield. The highest values of spike and stem contribution to grain yield were obtained under drought stress while current photosynthesis was found to be the sole supplier for grain filling in normal conditions. Application of extra nitrogen fertilizer under drought stress was found to reduce the loss of grain yield in some genotypes as a result of enhanced vegetative growth, reserve accumulation, and dry matter remobilization to the grain.

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1215-1226 A. Grégrová, V. Kružík, E. Vrácovská, A. Rajchl and H. Čížková
Evaluation of factors affecting crystallization of disparate set of multi-flower honey samples
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Evaluation of factors affecting crystallization of disparate set of multi-flower honey samples

A. Grégrová*, V. Kružík, E. Vrácovská, A. Rajchl and H. Čížková

University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Food Preservation, Technická 5, 16628 Prague 6 – Dejvice, Czech Republic;
*Correspondence: Adela.Gregrova@vscht.cz

Abstract:

Honey crystallization is considered to be a natural process during its maturing and an indicator of natural honey composition. However, consumer evaluation of honey crystallization is usually negative. Crystallization depends on honey composition and it is influenced by methods and conditions of honey processing and storage (mechanical and thermal treatment). The aim of this work was to identify and evaluate general factors which can affect crystallization of blend multi-flower honeys (a disparate set of samples). The following qualitative parameters were determined: a content of ⁵-hydroxymethylfurfural, furfural, glucose and fructose, water and diastase activity, moisture and an absolute pollen count. A degree of honey sample crystallization was assessed by a sensory analysis. Effects of the various qualitative parameters on the crystallization degree were statistically evaluated. The honey crystallization degree was found to be a qualitative parameter positively correlated with the absolute pollen count. Using a multi-regression method (a cluster analysis) it was proven that the ⁵-hydroxymethylfurfural and moisture parameters were suitable characters with certain explanatory power to classify blend honey samples according to their crystallization degrees.

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1227-1233 V. Hönig, L. Smrčka, R. Ilves and A. Küüt
Adding biobutanol to diesel fuel and impact on fuel blend parametres
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Adding biobutanol to diesel fuel and impact on fuel blend parametres

V. Hönig¹*, L. Smrčka², R. Ilves³ and A. Küüt³

¹Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamýcka 129, 16521 Prague 6, Czech Republic
²University of Economics, Faculty of Business Administration, Department of Strategy, W. Churchill Sq., 13067 Prague 3, Czech Republic
³Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE51014 Tartu, Estonia
*Correspondence: honig@af.czu.cz

Abstract:

One of the main arguments for the use of biofuels is environmental reason. Biofuels release significantly lower quantities of greenhouse gases (GHG) during the combustion opposed to conventional fossil fuels. Fatty acid methyl esters are commercially blended with diesel and bioethanol with gasoline. Biobutanol and bioethanol are using the same sources. Biobutanol can be used as a biofuel in internal combustion engines in the same manner as bioethanol. Application of biobutanol in diesel is rather marginal, but is definitely preferable in diesel engines in comparison with bioethanol. There are plenty of options to use biobutanol in diesel engines. The simplest are blends with diesel. Number of parameters can used to compare biobutanol with standard diesel. Fuel parameters are changing with the amount of butanol added. Maximum amount of butanol in diesel in order to prevent negative effects was assessed.

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1234-1240 V. Hönig, J. Táborský, M. Orsák and R. Ilves
Using gas chromatography to determine the amount of alcohols in diesel fuels
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Using gas chromatography to determine the amount of alcohols in diesel fuels

V. Hönig¹*, J. Táborský¹, M. Orsák¹ and R. Ilves²

¹Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamýcká 129, 16521 Prague 6, Czech Republic
²Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE51014 Tartu, Estonia. *Correspondence: honig@af.czu.cz

Abstract:

The European Union tries to reduce carbon dioxide production and reduce fossil fuel consumption. One way to achieve this goal is adding biofuels to regular motor fuels. Biofuels also decrease the production of other harmful substances. This paper evaluates the identification of n-butanol and isobutanol in diesel fuel. The application of n-butanol to diesel fuel is currently being considered. Alcohols blended into diesel fuel have been shown to have a positive impact on solid particle production, smoke emission, etc. Bioethanol and biobutanol can be easily produced from waste products as second-generation biofuels. The experimental part of the paper focuses on the identification of n-butanol and isobutanol in diesel fuel, as it has been previously used for detecting bioethanol additions in diesel fuel. Test samples with the following composition were prepared: 10% of ethanol in diesel fuel; 5%, 10%, 20% of n-butanol in diesel fuel; 5% of n-butanol and 5% of isobutanol in diesel fuel; 10% of n-butanol and 10% of isobutanol in diesel fuel. This paper deals with the use of gas chromatography (GC) in the evaluation of motor fuels. GC analysis can provide a sort of a fuel ‘fingerprint’ that shows the approximate distillation profile and can reveal the presence of other foreign fractions. Regular evaluation procedures using gas chromatography for the determination of a diesel fuel’s quality unfortunately do not exist at the moment. As it is shown, GC could provide very valuable information in fuel quality assessment, making it the method of choice for this procedure.

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1241-1252 A. Küüt, R. Ilves, V. Hönig, A. Vlasov and J. Olt
The impact of bioethanol on two-stroke engine work details and exhaust emission
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The impact of bioethanol on two-stroke engine work details and exhaust emission

A. Küüt¹*, R. Ilves¹, V. Hönig², A. Vlasov¹ and J. Olt¹

¹Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE51014 Tartu, Estonia
²Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamycka 129, 16521 Prague 6, Czech Republic
*Correspondence: arne.kyyt@emu.ee

Abstract:

This research is important for expanding the possibilities for using bioethanol as a fuel for internal combustion engines. Small displacement two-stroke engines are widely used as power sources for manual power units. By using bioethanol as a fuel for two-stroke engines, we significantly decrease the risk to human health. The main problems entailed with using bioethanol include achieving the required lubrication properties, more precisely, the poor mixing or immiscibility of ethanol and oil. In the course of the research, a breakthrough was achieved in solving the problem in order to produce a fuel mixture for two-stroke internal combustion engines. Results covered include the effect of the fuel mixture on the functioning surfaces of an engine, but also the composition of the exhaust emissions. The aim of the investigation is to examine the effect of bioethanol fuel on the details and fuel system of a two-stroke engine. Test fuels are gasoline E 95 and bioethanol (96.3%), mixed by two-stroke engine oil. The mixture of bioethanol and oil shows the best results in the test of the friction force. That means wearing is not problematic but the problem is corrosion and CO emission.

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1253-1259 P. Laurson and U. Mäeorg
Water and water clusters in biological systems
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Water and water clusters in biological systems

P. Laurson and U. Mäeorg*

Faculty of Science and Technology, Institute of Chemistry, University of Tartu, Ravila 14a, EE50411 Tartu, Estonia;
*Correspondence: Uno.Maeorg@ut.ee

Abstract:

Water is inherently a simple substance, but from Aristotle's time until today it raises a lot of questions. Living cells are about eighty per cent water. Organisms consist essentially of liquid water, which fulfils a lot of functions and should never be considered just an inert diluent. The unique properties of water are of fundamental relevance for human life and play a substantial role in many biochemical and biological systems. In the second half of the previous century, researchers came to an understanding about the differences between biological water and ordinary water. This article reviews previous studies on water function and its significance in biological systems. Present knowledge about water clusters, the understanding of water cluster role in biological systems and common methods used in the analysis of determining water clusters are examined in this paper.

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1260-1274 Õ. Paas, K. Reinhold and P. Tint
OHSAS 18001 contribution to real and formal safety elements in safety management system in manufacturing
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OHSAS 18001 contribution to real and formal safety elements in safety management system in manufacturing

Õ. Paas*, K. Reinhold and P. Tint

Tallinn University of Technology, Faculty of Economics, Institute of Business Administration, Chair of Work Environment and Safety, Ehitajate 5, EE19086 Tallinn, Estonia;
*Correspondence: onnela.paas@gmail.com

Abstract:

The current paper examines safety management systems in the Estonian manufacturing industry. The aim of this research is to assess via safety audit, to what extent OHSAS18001 contributes to real and formal safety elements of SMS in manufacturing companies. In 2014, eight OHSAS 18001-certified organisations and eight non-certified Estonian enterprises from different branches of manufacturing were interviewed and assessed using MISHA method. The results show via statistical analysis that OHSAS 18001 has a significant impact on formal safety, real safety and combined safety elements. It can be also concluded that the OHSAS 18001 certification facilitates companies’ commitment to health and safety activities and leads to dealing with additional topics promoting workplace health and safety. Therefore, OHSAS 18001 can be seen as a strategic unit for improving safety performance. However, after examining three types of companies, we can conclude that a safety management system can be effectively implemented also without possessing the OHSAS 18001 certification, but in the Estonian economy market it usually requires affiliation with a larger corporation or concern. Based on the analysis, a conceptual model is created which helps the company reallocate the resources in a way that all possible safety elements will be covered.

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