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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Vliv adhezní mezivrstvy na lomově-mechanické chování kompozitu PP + anorganické plnivo. / Influence of adhesive layer on the mechanical behavior of PP+ inorganic filler composite.

Švestková, Dana January 2011 (has links)
The diploma thesis was dealt with the study of system PP and particular filler, specifically PPH and like a filler was used commercially available CaCO3 (SOCAL P3). This type of filler is declared by the producer as a filler without surface treatment. The submitted thesis had a goal to find and testing the suitable method and methodology for defined surface treatment of the filler. This is the first step for systematic study of influence the various types of adhesive layer on mechanical properties of declared composite. The plasma discharge behind static pressure was used for the surface treatment of the fillers. These fillers were afterwards analyzed by using of sedimentation analysis, infra - red spectroscopy (FT-IR) and scan electron microscopy (SEM). The composites with various volume part of the fillers were prepared in PIB and studied by short-time tests. Regarding to experimental demand there wasn't possible to realize the whole originally intended program i. e. study of influence the different types of adhesive layer, including to form the model for FEM approach. Nevertheless finding and testing the suitable method of surface treatment is completely basic for the others study. The above mentioned method was used in this application for the first time and it is possible to consider this process like an original approach.
112

Stanovení tenzidů ve vodách pomocí separačních metod / Determination of tensides in waters by separation methods

Brestovská, Marta January 2015 (has links)
Surfactants are synthetically made surface-active agents contained in washing and cleaning products. They decrease the surface tension and remove dirt. Surfactants can be divided into three basic classes: anionic, cationic and non-ionic. Thanks to the massive use they penetrate into waste water and can disturb the environment. This diploma thesis deals with the occurrence of surfactants in water and their determination by separation methods, especially LC / MS.
113

Filtr s akustickou povrchovou vlnou / Surface acoustic wave filter

Tichý, Jakub January 2010 (has links)
The theoretical part of this thesis deals with principles and characteristics of the surface acoustic wave filter. It explained the principle of magnetostriction and piezoelectric effect, which uses a filter. In the practical part in the program Comsol Multiphysics are made three simple models of SAW filter. Some modes are founded and are compared to previously known results. In the next phase of project is further studied using the parametric analysis. In the last phase of project is applied global optimization PSO at admittance characteristic from simple 2D structure. The results are compared with the commercially produced devices.
114

Termomechanická spolehlivost montáže mikroelektronických a elektronických modulů / Modern Assembly for Microelectronic and Electronic Modules

Janík, Pavel January 2010 (has links)
Project is focused on describe modern assembly of microelectronic and electronic modules in electronic devices. Sense of the project is analyse reliability and inadequacies electronic devices assembled by modern technogies. Inadequacies modern technologies are impulse for design, implementation and testing new our way of assembly microelectronic modules. Main kind of materials which are used in this project are ceramics Al2O3 and printed circuit board FR4.
115

Termomechanické namáhání bezolovnatého pájeného spoje / Thermomechanical Stress of Lead Free Solder Joint

Libich, Jiří January 2011 (has links)
This diploma thesis deals with the reliability of lead-free solder joints at a different interconnection structures. The first goal is to design the test cases shape BGA (FC) for testing the strength of lead-free solder joints at shear test in link with design of measuring method to detection shear strength during isothermal aging of lead-free solder joints. Following this shear stressing is investigating influence material and process compatibility, ie. pads finishing, material of solder and integrate of temperature (this mean thermal energy supplied during soldering) to lead-free solder joint strength.
116

Antikorozní úpravy povrch elektromotoru / Anticorrosive modification of electric motors surface

Vlčková, Irena January 2013 (has links)
This Master´s thesis is devoted to the basic theory from semester project. There are describe completed practical tests, measurements and results. This project was written below patronage of company Siemens s.r.o. odštěpný závod Elektromotory Mohelnice, which is at the same time also my employer. There is production of asynchronous electromotors frame size 56 to 200. On the all of electromotors is desired quality surface treatment with difference on the base of request of customers.
117

Remediační potenciál huminových kyselin / Remediation Potential of Humic Acids

Uhrová, Anna January 2016 (has links)
V předložené práci byly testovány modifikované lignitické huminové kyseliny za účelem zjištění jejich schopnosti remediace zemědělské půdy. Před samotnou extrakcí jednotlivých huminových kyselin byl lignit modifikován jednou ze série deseti organických kyselin. Cílem modifikace byla simulace procesů vyskytujících se v rizosféře, tj. procesů, kdy malé organické molekuly způsobují změny ve struktuře půdní organické hmoty, během nichž dochází k produkci biologicky aktivních agregátů/molekul podílejících se na růstu rostlin. Prvním krokem této práce bylo zkoumání fyzikálně chemických vlastností vyprodukovaných huminových kyselin a jejich molekulové struktury prostřednictvím elementární analýzy, infračervené spektroskopie s Fourierovou transformací (FTIR), vysokoúčinné gelové chromatografie (HPSEC), metodou měření povrchového napětí a plynovou chromatografií s hmotnostní spektrometrií (GC-MS). Dalším krokem bylo studium parametrů biologické aktivity, získaných z experimentů zaměřených jak na vyšší rostliny, tak na remediaci mikrobiologické aktivity zemědělské půdy. Biologická aktivita vůči vyšším rostlinám byla zkoumána na základě experimentu s kukuřicí, byla měřena délka a hmotnost kořenů, rozvětvení jejich laterálních kořenů a obsah sacharidů a proteinů. Z experimentů cílených na půdu se jednalo o měření množství uvolněného CO2 při laboratorní inkubaci ošetřené půdy a půdní hydrofobicitu (metoda měření kontaktního úhlu). Na závěr byly výsledky podrobeny statistické analýze s využitím Pearsonova korelačního koeficientu s cílem nalézt vztahy mezi fyzikálně chemickými vlastnostmi a biologickou a povrchovou aktivitou studovaných huminových kyselin. Korelace byly zjištěny mezi biologickou aktivitou a fyzikálně chemickými vlastnostmi huminových kyselin. Naopak, nebyly zjištěny mezi povrchovými a fyzikálně chemickými vlastnostmi. Nejefektivnějším modifikačním činidlem z pohledu biologické aktivity byla 20% kyselina mravenčí, nejméně efektivním 20% kyselina propionová.
118

Komparativní analýza vybraných bruslařských způsobů v běhu na lyžích / Comparative analysis of chosen skating techniques at cross-country skiing

Kmoch, Jan January 2011 (has links)
Author's first name and surname: Jan KMOCH Department: FTVS UK, Department of Outdoor Sports Supervisor: Mgr. Radka Bačáková Abstract Title: Comparative analysis of chosen skating techniques at cross-country skiing. Objective: Comparison of leg muscle coordination at different skating techniques in one locomotive cycle at cross-country skiing and free bipedal walk. Methods: Comparative analysis of electromyography records of muscle activation in combination with kinematography analysis of video record. Results: There were found similarities and differences in muscle activation timing at observed muscles. Keywords: skating at cross-country skiing, bipedal walk, surface electromyography
119

MUSCLES ACTIVATIONS DURING "SHOULDER MOUNT" POLE ACROBATIC EXERCISE

Sanni, Modinat January 2016 (has links)
Author: Bc. Modinat Sanni Supervisor: Ing. Miroslav Vilímek, PhD Title: MUSCLES ACTIVATION DURING "SHOULDER MOUNT"POLE ACROBATIC EXERCISE Purpose: This study is an empirical - theoretical study presents the literature review regarding to the topic of the shoulder function anatomy, kinesiology, biomechanics, non-traumatic injuries of the shoulder and their prevention by using the available literatures. Further, the study also compares by surface electromyography the amplitudes, shapes and durations of myoelectric signals of m. latissimus dorsi, m. pectoralis maior, m. biceps brachii, m. infraspinatus and m. supraspinatus of dominant shoulder in two healthy individuals during acrobatic exercise on vertical pole known as "Shoulder Mount". The purpose was monitor the changes in two different conditions; i.e. kinesiotape and elbow brace and compare with the control condition for the reason of finding out their ability to affect the myoelectric activities of selected muscles. Further, the Shoulder Mount exercise had recorded by six Qualisys cameras for motion analyses. Methods and materials: The potentially eligible scientific articles perform a search of studies on the topic of kinesiotapes and tennis elbow brace as measured by EMG mainly on myoelectric activity of the shoulder complex were seared from...
120

Exoskopický standard sedimentů glacigenních akumulačních forem reliéfu / Exoscopy of sediments of glacigenous accumulation landforms

Křížová, Lenka January 2010 (has links)
This thesis looks at the comparison between grain micromorphology of moraines, debris flows and similar accumulations. Moraine samples were taken in the Černé jezero Lake area, Bohemian Forest, in the Velická dolina Valley, High Tatras, and in the Labský důl Valley, Krkonoše Mts. Samples of debris flows and unverified accumulations were taken in the Důl Bílého Labe Valley, Krkonoše Mts., and further samples of accumulations were obtained from the valley of Prudký potok Stream, Králický Sněžník Mts., the valley of Vražedný potok Stream and Velká Kotlina, Hrubý Jeseník Mts. Sediments were examined under electron microscope and their morphological characteristics and influence of the environment were identified and described. Calculated exoscopic moraine standard was used for comparison of examined forms of relief using distance coefficients, statistical analysis were carried out which identified diagnostic characters for distinguishing moraines and debris flows. There was also calculated exoscopic standard for different types of moraines (frontal, lateral, basal). This research highlighted the differences between moraines and debris flows, and between different types of moraines. The study also proved that typical glacial microtextures, that are generally accepted, occur at similar levels on grains...

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