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Temperature Measurement in Technical Diagnostics
Szmek, Tomáš ; Janečka, Jan (referee) ; Vdoleček, František (advisor)
The purpose of this bachelor’s thesis is to familiarize a reader with possibilities of temperature measurement along with constructions and functions of particular measuring instruments and to present their positive and negative aspects. Both basic contact thermometers used in common life and complex systems (thermovision) employed in the most demanding industrial application are described here. The thesis depicts temperature as a diagnostic value according to which the causes of machinery failures are easily detected and subsequent accidents prevented.
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Utilize of instrumentality PSE (Pressurized Solvent Extraction) in food analysis
Grulichová, Hana ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is engaged in the modern method of extraction PSE (pressurized solvent extraction). There have been two types of this apparatus, One PSE and Fast PSE. In this thesis, the apparatus and its behavior is described. Extraction of anthraquinones, strychnine, berberine, glycyrrhizin, ligustilides from medical plants is presented below. These substancies are used mainly in treatment for various diseases. In this work is noticed trace elements, tocopherols, alkylbenzene sulphonate, isoflavone, dionine, betacarotene, vitamin E, polyphenol extracted from biological samples. Utilization of the substancies from biological samples is very different. Some one decreased risk of osteoporosis, cardiovascular disease, cancer and other is by contrast deleterious toxin. High attention is devoted to substancies presented in food such as polychlorinated biphenyls, various pesticides, lipids, oxysterols. These substancies are in food rather undesirable than is why their amount is determinated to the food isn´t deleterious.
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The Bowen Ratio/Energy Balance method and detailed temperature profile measurements to improve data quality control
Pozníková, Gabriela ; Fischer, Milan ; Orság, Matěj ; Trnka, Miroslav ; Žalud, Zdeněk
Water plays a key role in the functionality and sustainability of ecosystems. In light of predicted climate change, research should focus on the water cycle and its individual components. The main component of water balance driving water from ecosystems is evapotranspiration (ET). One standard method for measuring ET is the Bowen Ratio/Energy Balance (BREB) method. It is based on the assumption that water vapour and heat are transported by identical eddies with equal efficiency. When using the BREB method, we assume that the profiles of temperature and air humidity are ideally logarithmic or at least consistent. Since the BREB method is usually based on measurements of temperature and humidity at only two heights, it is difficult to verify whether this assumption has been fulfilled. Potential profile inconsistencies are more likely for temperature because the sensible heat flux changes its sign more often and negative latent heat flux is not physically possible during positive sensible heat flux. We therefore conducted a field experiment using a 4-mhigh measurement mast with 20 thermocouples for detailed measurement of air temperature profiles above different covers, e.g. grassland, spring barley, and poplar plantations. Our main objective was to investigate the basic assumptions of the BREB method, i.e. the temperature profile’s consistency under various weather conditions. To be more specific, we aimed to investigate whether inflexion points occurred within the temperature profile and if so when.
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High night temperature-induced accelerated maturation of rice panicles can be detected by chlorophyll fluorescence
Šebela, David ; Quiňones, C. ; Olejníčková, Julie ; Jagadish, K. S. V.
Rice panicle maturation is considered to be highly sensitive to environmental conditions. Since one of the factors accompanying global climate change is increases in minimum night temperatures more pronounced than those in maximum day temperatures, the effect of high night temperature (HNT) on rice panicle maturation was investigated. Two rice genotypes with contrasting HNT responses, N22 (highly tolerant) and Gharib (susceptible), were exposed to control temperatures (ca 23°C) and HNTs (ca 29°C) from flowering until maturity. Loss of photosynthetic activity and/or pigments during rice panicle maturation were evaluated temporally by measuring (i) effective quantum yield of photosystem II efficiency (ΦII), and (ii) steady-state chlorophyll fluorescence level (FS). To prove the accuracy of the new approach presented in this study, several vegetative indices were calculated from reflectance measurements and correlated with fluorescence parameters. It has been observed that ΦII tracks the accelerated maturation of rice panicles exposed to HNT better than does FS. Employing a newly identified chlorophyll fluorescence-based parameter could potentially enable larger genetic diversity scans and identification of novel genotypes with longer panicle maturation periods so as to increase rice yields directly under field conditions.
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