Spelling suggestions: "subject:"částic"" "subject:"nanočástice""
91 |
Příprava vzorků pro analýzu DNA v potravinách rostlinného původu / Sample preparation for DNA analysis from foods of plant originSilná, Renata January 2018 (has links)
The isolation of high quality DNA is nessecary for many molecular biology applications. However, plant DNA contains high amonts of polysaccharides, polyphenols and various secondary metabolites, which decrease yield and quality of isolated DNA. The aim of this study was preparation of samples and different food matrices for DNA isolation DNA by magnetic particles. It was about 5 species of vegetable and 10 species of processed plant food. Homogenization of samples was performed in CTAB buffer. Isolation of plant DNA was performed by magnetic particles covered with carboxyl groups. All DNAs were isolated in conventional PCR qualities using primers for 700 bp amplicons, in the case of heat processed products for 220 bp ampilicons and for real time PCR. The efficiancy of separation of magnetic particles with DNA by magnetic separator and magnetic needle was compared. It was find out that DNA of higher purity was isolated using magnetic needle. The micromethod of isolation of plant DNA from homogenates with CTAB with magnetic particles is suitable for different processed food.
|
92 |
Vliv kontaminace a degradace maziva na chování mazacího filmu / The effect of lubricant contamination and degradation on lubricating film behaviorStrnad, Jan January 2018 (has links)
Lubrication contamination and degradation is one of the major causes of unexpected failure of tribological nodes. As a result, different levels of maintenance are introduced in practice, leading to a longer service life of the lubricated node. These systems often include sophisticated on-line diagnostic tools that can be used to evaluate a sample of a lubricant using certain variables such as viscosity, number of particles, humidity, dielectric constant, etc. Based on changes of these variables some systems can make corrective measures such as filtering or complete replacement of lubricant. Therefore, the aim of this experimental thesis is to determine the influence of lubrication contamination (solid particles, moisture) and degradation (oxidation) on the lubricating film behavior with respect to its limit bearing capacity. To examine the thickness of the lubricating film, friction and wear, an optical and MTM tribometer, in the ball-on-disc configuration, was used.
|
93 |
Opimalizace typů, granulometrie a tvaru jemných částic pro speciální betony / Optimization of types, granulometry and fine particle shape for special concreteJobánek, Jaromír January 2019 (has links)
This diploma thesis is focused on optimization of particle size distribution using concrete additions. To design a concrete of excellent properties, it is often necessary to achieve a higher packing density of the mixture by designing a suitable particle size distribution curve. Concrete with special properties and various types of powder additions are also described.
|
94 |
Pokročilé kompozitní konstrukční oceli pro použití v taveninách těžkých kovů / Advanced Composite Structural Steels for Applications in Heavy Liquid MetalsHusák, Roman January 2019 (has links)
Doctoral thesis was focused on preparing of new advanced ODS steels for use in heavy metal liquids enviroments. Possibility of new course for creating oxide dispersion in microstructure was verified by the course of internal oxidation of elements. By the internal oxidation method were prepared new ODS steels strengthened by complex oxides which were created by elements of IIIB and IVB group of elements. Based on analysis of damage ODS steels in LBE were designed surface protection of ODS steel by the oxide layer. The ODS steel protected by oxide layer was subjected to a corrosion test in LBE. For the experiments were chosen class of chromium steels: ferritic-martensitic steel 9Cr1WMnVTa and ferritic steels 14CrWTi and 17Cr1Mo. Steels without oxide dispersion and steel strenghtened by the dispersion based on Y-Ti-O oxides were prepared. On the steels were made series of mechanic tests which should reveal the effectivity of oxide dispersion on the strenght of steel prepared by the internal oxidation method and by the direct addition of oxide elements. It was found that significantly harder oxide material couldn't be fully disrupted through the mechanical alloying and fine oxide dispersion couldn't be created. There was verified fine oxide dispersion could be created by the internal oxidation method and by the direct adding of oxide elements. Same kind of steels strenghtened by new kind of complex oxides based on Y, Ce, Hf, La, Sc and Zr were prepared. The chemical analyses have proven that all added elements could created complex oxide by the reaction with yttrium. The computational analyses for observing of matrix influence and oxide phase influence on strenghtening of steels were performed. These computational analyses were based on microstructural analyses of ODS steels. There was found that the oxide particles could very effectively improve strenght of steels at room temperature and especialy at high temperature. Based on corrosion tests of 14Cr ODS steel in liquid Pb and LBE enviroment were designed surface protection of ODS steel. The effectiveness of protective layer was verified by the high temperature corrosion test of PM2000 in LBE. No damage of oxide layer was observed although Pb and Bi diffused through protective layer.
|
95 |
Využití různých metod izolace DNA baktérií mléčného kvašení v molekulárně biologických metodách / Using different methods of DNA isolation of lactic acid bacteria in molecular biological methodsChvalkovská, Eva January 2019 (has links)
This thesis focused on the probiotic bacteria, DNA isolated from these bacteria by three different methods and the effect of isolation on DNA identification using molecular biological methods. Probiotic bacteria are an important part of human intestinal tract. They have an important role in the function of the immune system due to adhesion to the mucosa of the intestinal flora. They create a inhostile environment for pathogens. Probiotic bacteria are commonly taken in the food like dairy products or food supplements. However, overuse of antibiotics is at risk of passing on the intrinsic resistance that probiotic bacteria have to the pathogenic bacteria. The intrinsic resistence they have to maintain the natural homeostasis of the intestinal tract. It is important to effectively identify risky probiotic bacteria that have the ability to transmit resistance to eliminate their presence in food and dietary supplements. Three methods of DNA isolation like phenol extraction method, magnetic particle isolation and commercial kit isolation were used in the experimental part. DNA was isolated from three dietary supplements, namely Biopron 9 premium, Linex forte and GS Lactobacily forte 21. The purity and concentration of the isolated DNA was detected spectrophotometrically. The presence of individual DNA strains in dietary supplements was confirmed by real-time polymerase chain reaction. The best method of isolation in terms of purity and concentration of isolated DNA was evaluated by RT-PCR and spectrophotometry using a commercial kit isolation method.
|
96 |
Optimalizace izolace plazmidové DNA pomocí magnetických částic / Optimization of plasmid DNA isolation by magnetic particlesChlopková, Barbora January 2019 (has links)
The theoretical part summarizes information on the isolation and purification of plasmid DNA and nucleic acids as. Plasmid DNA is often used in gene engineering as a vector for the transfer of a particular gene. Its insulation and transportation in sufficient quality is crucial for other processes associated with it. Isolation and survival of pDNA using magnetic carriers of different concentrations of PEG 8000 in combination with 1M NaCl was investigated in experimental parts. Furthermore, the isolation of pDNA using commercial kits was examined.
|
97 |
Analýza namáhání vybraných konstrukčních částí bagru při provozu / Analysis of mechanical loads of selected structural parts of the excavator during operationBusta, Michal January 2021 (has links)
This thesis is focused on the issue of computational modeling of soil harvesting while using the compact excavator from the company DOOSAN BOBCAT EMEA s.r.o.. The solution consists in creating two computational models in Rocky DEM and Ansys Mechanical. Rocky DEM software is used to solve the disconnection of soil by excavator components using the discrete element method. The outcome includes courses of forces and moments during the particular time of the individual joints of the model that was used. The obtained courses are then applied as an external load to the joint of a selected structural part of the analyzed model using a kinematic model in ANSYS Mechanical. The kinematic model consists of simplified geometry models of individual parts of the excavator arm, and a more detailed geometry model of the analyzed part of the arm. All the parts are connected to each other by rotational bonds representing joints. A static structural analysis of the mechanical stress is performed in ANSYS Mechanical for the prepared model during the simulated process. Finally, the selected structural part is assessed with respect to the elastic limit and fatigue strength.
|
98 |
Odstraňování mikroplastů z vody / Microplastics removing from waterErmis, Martin January 2021 (has links)
This thesis deals with the occurrence of microplastics in water, the reasons for their potential elimination, and the possibilities leading to that. More specifically, it focuses on flotation as a process for removing microplastics from water. Flotation is further described from a theoretical point of view and its mathematical model is developed. The wettability of selected polymers is measured. The experiment performed to determine the efficiency of flotation as a process of treating water from microplastics is described. This efficiency is further compared to measured wettability.
|
99 |
Vliv intenzity dopravy a meteorologických podmínek na znečištění ovzduší / Influence of traffic volume and meteorological conditions on the air pollutionVojtěchová, Ivana January 2009 (has links)
Transport, whose intensity year by year increase, has assuredly influence on air quality. This issue solution will be focused especially on localities burden with transport in urban areas. The contribution of transport to increased values of air pollution will be evaluated with regards to meteorological conditions. Background stations from Czech Hydrometeorological Institute categorization will be chosen such as comparative sites. Pollutants emitted from traffic such as particulate matter, nitrogen oxides and carbon monoxide will be observed except meteorological conditions.
|
100 |
Izolace DNA z probiotických výrobků s využitím pevných nosičů / Isolation of DNA from probitic products using solid carriersBonczek, Ondřej January 2011 (has links)
Microbial DNA was isolated from lysed cells of Lactobacillus genus in probiotic products. Reversible adsorption DNA on the surface of carboxyl coated nonporous poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) magnetic particles and silicagel coated manganase Perovskite nanoparticles. DNA was adsorbed on the surface of the particles in the presence of 16 % poly(ethylenglycol) (PEG 6000) and 2 M sodium chloride (NaCl) concentrations. The adsorbed DNA was released from particles by low ionic strength TE buffer (pH= 8.0). The quality of isolated DNA was checked by spectrofotometric measurement and PCR amplification. DNA samples isolated using magnetic particles and phenol extraction method (control method) were PCR-ready. The DNA isolated from lysed cells of probiotic products was quantificated in real-time qPCR.
|
Page generated in 0.0472 seconds