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The impact of digestate fertilisation on the structure of yield and selected qualitative indicators of potatoes.
Polák, Miloslav ; Hamouz, Karel (advisor) ; Pavel, Pavel (referee)
The thesis studies the effect of digestate fertilisers on the structure of yield, starch content and scab of potato tubers. The introduction outlines the problems of potato fertilisation, including the existing knowledge on the fertilisation by digestate. The subsequent, experimental part was executed in the form of a field experiment in SENAGRO Senožaty a.s. This enterprise produces table potatoes for TESCO chain of supermarkets. The company was interested in using the waste material (digestate) from biogas station as efficiently as possible and tried to use it as a dose of nitrogen under potatoes. The company uses the technology of destoning with a line width of 90 cm.
The experiment was carried out in such a way to enable to determine the effectiveness of digestate as a substitute for the usual N fertiliser for potatoes. It was based on three variants: Variant A. Ammonium sulphate applied areally before destoning and 15-15-15 local application of NPK fertiliser (in total dose of 100 kg N/ha). Variant B. Ammonium sulphate + NPK + DAM 390 applied during vegetation on 27th May 2015 (in total dose of 120 kg N/ha). Variant C. Digestate in quantity of 120 kg N/ha. Early to midseason Luciana variety was used in the experiment.
In compliance with the methodology, before the harvest I dag away the bushes to find out the level of yielding elements. I took samples that were evaluated in terms of starch content in Vesa Velhartice, and personally examined the scab of potato tubers. On the basis of statistical evaluation of the examined variants (executed at the Department of Crop Production), I reached the following findings:
Compared to the usual variants of N fertilisation, digestate fertilisation of potatoes did not have any statistically significant effect on the weight of tubers under one bush or the weight of table potatoes. Compared to the control variants of N fertilisation, digestate fertilisation did not influence verifiably the total number of tubers per one bush or the number of table potatoes per one bush. In terms of the effect on the average weight of one potato, the variant
with the application of digestate fully equalled, or even exceeded, the experimental variants of mineral N fertilisation. It is therefore possible to say that in terms of yield, this type of fertilisation can serve as a substitute of fertilisation by nitrate and mineral fertilisers. Starch content and scab of potato tubers were not demonstrably influenced by digestate fertilising compared to traditional N fertilisation.
In conclusion, I would like to point out that the experiment has been carried out only for one year and its results cannot be generalised yet. That is why I recommend to continue in the experiment also in the future years.
In my opinion, digestate and the problem with its application is becoming an increasingly pressing theme. If experiments carried out for several years prove that the result of its application is positive to potatoes, digestate, in my opinion, will again have broader possibilities of use and we can count with it as a full-value fertiliser also in the future.
Keywords: potatoes, digestate, starch content, scab, yield
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Comparison of composite material degradation assesment methods using acoustic analysis and laser vibrometry
Urushadze, Shota ; Šperl, Martin ; Kytýř, D. ; Valach, J. ; Fíla, T.
Assessment of degradation rate of material can be carried out by many experimental techniques differing in complexity and sophistication. A relatively simple method based on acoustic analysis is described in this contribution. Degradation of material’s properties due to fatigue loading is detectable in decrease of their modulus of elasticity that can be derived from natural frequencies of specimens. These measurements utilize self-designed device capable of specimen excitation and acquisition of its vibration. The recorded signal is then processed by spectral analysis enabling determination of natural frequencies. Usefulness of the above mentioned acoustic method can be seen in the fact that the measured changes of material’s parameters are comparable to those obtained by laser vibrometry, which is by several orders more expensive technique.
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Economic aspects of brownfield regeneration in South Bohemia
PŘIBYL, David
The purpose of this thesis is to highlight the issue of brownfields. Green Meadow is still dominant because investors often care about making their edifice was built on the spot where now nothing happened, but on the other hand, brownfields have their advantages and disadvantages. The content of this paper is a general definition and the definition of terms as they are perceived by organizations that issue. The aim of this thesis is to evaluate the economic regeneration of brownfield sites in selected South Bohemian region consisting of the assessment of costs and benefits associated with brownfields. Brownfields selection was made based on the availability of information and the suitability of the sample for evaluation.
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Current trends in material handling technology
Olšerová, Tereza ; Hladík, Tomáš (advisor) ; Aleš, Zdeněk (referee)
The aim of this work is to prepare an overview of current trends in materials handling division and its uses in logistics and manufacturing. The individual chapters are grouped by kinds of manipulation techniques, which are available on the market today, along with possible ways of its acquisition. Chapter Optimization methods of handling technology focuses on modern methods, which are used to optimize handling equipment in enterprises. These methods focus on optimizing the quantity, type and method of handling. In the chapter Current trends in handling technology is research for monitoring of handling technology using cameras and computational algorithm to determine routes.
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Drying of moist materials at low temperatures
Gregor, Jakub ; Neuberger, Pavel (advisor) ; Adamovský, Radomír (referee)
The aim of this work was to develop a literature review on the issue of drying moist materials at low temperatures. The first part is devoted to an overview of drying theory, distribution and classification of dryers and a brief analysis of the most common of them. There is also addressed the issue of the effect of temperature on the dried material and the nature of low-temperature drying.
The second part of the research is concerned with the broadest current method of drying at a low temperature, which is called lyophilisation. There is mentioned principle of the method, the process of drying, processing equipment, methods and examples of activities and overview of key manufacturers.
The third part is devoted to other drying techniques that can be used for effective drying at low temperature and their comparison.
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Risk element sorption on waste materials from olive oil production
Hovorka, Miloš ; Száková, Jiřina (advisor) ; Trakal, Lukáš (referee)
The main objective of this thesis is to verify the efficiency of waste material from olive oil production to immobilize risk elements Pb, Cd and Zn in extremely contaminated soil and to verify following hypothesis: application of waste material from olive oil production will limit the availability of risk elements in the soil and also improves a supply of soil available nutrients and biological properties of the soil. The work is divided into two parts, theoretical part (literature review) and experimental part.
The theoretical part contains a general description of the risk elements and their possible harmful effects on living organisms, indicating their possible sources of entry into the environment, describes the behavior of these elements in the soil, especially events that contributes to the retention of soil. Furthermore, there are some possible methods for remediation of soil contaminated with hazardous elements and is described in more detail immobilization technique using soil improvers. In this chapter is devoted to the waste material from olive oil production, whose properties are tested in the experimental part of this work.
The experimental part is focused on verification sorption capability of waste material from olive oil production for selected risk elements. As a waste material has been used dry olive residue (known as DOR), and DOR after remediation of these types of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkandela adusta and Chondrostereum purpureum. Analytical methods were used to determine the concentrations of the elements, the pH, the point of zero charge (pHpzc), and cation exchange capacity (CEC) for the individual samples representing material DOR and DOR after remediation of certain species of fungi. The preliminary sorption experiment determined sorption efficiency for the elements Cd, Pb and Zn for all the material tested. Stability of the risk element bonds was verified via model desorption experiment. Model laboratory incubation experiment was carried out to assess the potential changes of hazardous elements mobility in the contaminated soil, depending on dose and type of DOR material. At the same time there were determined contents of available proportions of essential elements in the soil. The contents of elements were determined by atomic spectrometry (ICP-OES) and the results analyzed by adequate statistical methods.
Results showed good sorption capacity of the waste material DOR, especially after transformation with different species of fungi, for hazardous elements and particularly Pb, less then Cd and Zn. The desorption experiment, however, showed unstable linkages elements in samples DOR, particularly in the case of Zn, which is also reflected in the incubation experiment. This instability is probably due to the low pH material DOR, therefore it would be useful for further research take into account the increase of pH levels of these samples. In terms of elemental composition appears to be biotransformed DOR as a good source of nutrients. The treatment of thesoil increased accessibility of nutrients such as Cu, Fe and Mn for plants.
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Trends in the design and creation of new materials
Kašičková, Václava ; Gaff, Milan (advisor) ; Babiak, Marian (referee)
Thesis investigates the flexural properties of modified laminated wood. Thesis examined two wood species - beech and aspen. The aim was to describe effect of wood species, material thickness, densification, adhesives and loaded cyclic stress on selection of mechanical properties.
Wood species and thickness of material were determined as factors with very significant impact. They affected modulus of elasticity, limit of proportionality and bending strength. All these characteristics achieved higher values while testing beech lamellas. Degree of densification does not appear as a very significant factor. Comparing modulus of elasticity in this thesis and data given in the literature it is possible to say that densified lamellas used in this research reached higher values.
This thesis also investigates tensile-shear strength and bendability.
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Mechanical properties of the lamellae materials
Vokatý, Vojtěch ; Gaff, Milan (advisor) ; Babiak, Marian (referee)
This thesis evaluated experimental research on the influence of selected factors (species, thickness, density, number of stress cycles) on the specified material characteristics (modulus of elasticity, modulus of rupture, limit of proportionality, bendability coefficient). The measured values were statistically evaluated and expressed in tables and graphs. Beech (Fagus Sylvatica L.) was selected to represent hardwood and aspen (Populus Tremula L.) softwood.
Tree species affects all observed characteristics. The results show that the modulus of elasticity increases with increasing densification of the material, but decreases with the increasing thickness of the material. A similar dependence is observed even with the modulus of rupture and limit of proportionality, which is also dependent on the number of cycles. The bendability coefficient is affected by material thickness.
It is expected that based on the evaluation of the results it will be possible to design materials with tailored properties.
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Principles targeted Edit the properties of layered materials
Houžvíček, Petr ; Gaff, Milan (advisor) ; Gašparík, Miroslav (referee)
Target of the thesis was an investigation of the influence of selected factors (tree species, thickness of material, type of glue and cyclic loading) and their combinations on strength properties of laminated lumber. This measured properties were: bending strength, modulus of elasticity, limit of proportionality, coefficient of bendability and shear strength of glued joint.
Most important factor for bending strength, modulus of elasticity and limit of proportionality was the tree species. For coefficient of bendability and shear strength of glued joint the most important was the material thickness. Influence of cyclic loading and type of glue, weren´t proved.
After that, we simulated our investigation which we made in computer program based on finite element method. The simulation corresponded just for thicker tested samples.
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