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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.
261

Metody značení těla a potravy hmyzu a jejich využití u včel (Anthophila) / Methods of insect body and food marking and their utilization in bees (Anthophila)

Macháčková, Lenka January 2021 (has links)
Marking methods represent often an essential part of many studies which target on insect biology. These marking techniques sometimes represent the only possible way to obtain new and important informations. In the first part of the thesis I deal with individual insect labeling, which was used for marking of solitary bees and their nests as a tool of obtaining informations about nesting bee dynamics in aggregation. Our study show that nest owner replacements are very common in all four species. However, a large percentage of the nests were abandoned by the female owners before owner change. Only a part of all the nests were trully usurped on the nesting site. The true usurpations thus represent rather minor part of observed nest owner replacement situations. The bees surprisingly often abandon their nests and found the new ones. The frequent contacts of the females on a nesting site occur as a result of common nest owner replacements. High tolerance of bees to each other together with tolerance of usurpations and low level of aggression may thus represent one of the possible ways towards communality and other types of social behaviour. In the second part of the thesis I focus on the possibilities of food marking in bees. Effectivity of sugar and pollen utilization are not yet fully understood in...
262

Stanovení mikroprvků v mléce pomocí ICP-OES po extrakci technikou DGT / Determination of microelements by ICP-OES after extraction by DGT technique

Habartová, Aneta January 2020 (has links)
This thesis is focused on determination of microelements (Cd, Co, Cu, Fe, Mn, Ni, Pb a Zn) in milk by optical emission spectrometry with inductively coupled plasma (ICP-OES) after extraction by Diffusion Gradients in Thin films technique (DGT) containing Chelex 100 resin gel and agarose diffusion gel. The optimalization of DGT in model metal solutions was verified by recommended basic tests. The performance of the DGT technique in the diluted milk matrix was verified. By DGT technique was determined only Zn in real milk matrix with concentration 3,74 ± 0,02 mg/l. The other microelements in the prepared eluate were at or below the limit of detection of the instrumental method. The obtained results were compared with the analysis of milk after microwave digestion by ICP-OES. However, these results were below the detection limit of the device too, only Zn with concentration 3,91 ± 0,16 mg/l was measured. For the future analysis of the selected microelements in milk by DGT technique, further optimization of the preconcentration technique is required, or use of a more sensitive instrumental method.
263

Možnosti určení původu vína z prvkového složení / Possibilities of determining the origin of the wine from the element composition

Škařupa, Přemysl January 2012 (has links)
The aim of this diploma thesis was to evaluate the possibility of determining the origin of the wine on the basis of elemental composition. For this purpose an analysis of major and minor elements was accomplished in selected varieties of wines. In total, 48 parameters for six wine subregions in Bohemia and Moravia was determined and used. The sum of 35 parameters represented the concentration of selected elements and other 13 parameters were created from the measured values. The concentration of elements was determined by inductively coupled plasma mass spectrometry (ICP-MS). For the purpose of classification of samples into groups multivariate statistical methods were used. The measured data set was firstly separated using analysis of variance (ANOVA) and discriminant analysis (DA). It has been proved that the selected variables influence the distribution of wines into categories according to their geographic location. Canonical discriminant analysis, principal component analysis (PCA) and cluster analysis has been used for graphical projection. Simultaneously the model based on our analysis was created to enable classify an unknown sample of wine according to the origin.
264

Sledování uvolňování cínu do konzervovaného ovoce z použitých obalů / Monitoring of the tin release to the canned fruit from the used packaging

Flajs, Roman January 2015 (has links)
This master’s thesis deals with the issue of the release of tin in canned fruit of used packaging. The theoretical part of the thesis is described canning fruit as raw material, its composition, methods of preservation, basic technological operations fruit processing, manufacture of compote, manufacture of metal packaging, marches corrosive metal packaging, chemical behavior of tin in foods and toxicity, methods for the determination of tin in foods with a focus on optical emission spectrometry with inductively coupled plasma. I the experimental part of the thesis was first ICP-OES optimized before to analysis of the 20 different samples compote purchased in chain stores. Tin concentration was determined by a fixed proportion compote. Measured concentration of tin were compared with the maximum permissible value in canned foods, which is allowed by European legislation. The tin content in all analyzed compote did not exceed the legislative limit of 200 mg/kg. The highest concentration of tin has been measured in sample conserved apricots namely 88,6 ± 2,8 mg/kg.
265

Analýza vybraných prvků v mléce technikou ICP-OES / Analysis of selected elements in milk by ICP-OES

Sekaninová, Renáta January 2015 (has links)
This Master's thesis is dealing with elementary analysis of milk. Theoretical part describes general characteristics, terminology with basic legislature and classification of milk. Large part is focused on chemical composition, especially on description of mineral substances selected for analysis in experimental part of this thesis. Choices of elementary analysis and preparation of samples for ICP-OES method conducted by other authors are also mentioned. Specification of emission spectrometry with inductively coupled plasma is crucial, a technique used for purposes of this dissertation. Experimental part deals with preparation of samples, approach of analysis and processing of measured results. The aim of this part is to compare concentration of analyzed elements in different kinds of milk. Samples from 15 different kinds of milk were used for analysis, which were determined by ICP-OES method. Results were compared to each other in discussion as well as with results from other authors.
266

Tvorba IMS aplikací / IMS aplication creation

Nagy, Ľuboš January 2009 (has links)
This thesis describes basic principles of IP Multimedia Subsystem, known as the IMS, and shows the possibility for design applications using IMS. Firstly, a generic architecture IMS as layer model divided into four logic layer with definition the interfaces and the main entities is described. The IMS is based on SIP and IP protocols. Then is the architecture of SIP with the main entities explained. Structure of packet, request and response method in the part of SIP is also described. After that, three network services, namely presence services, instant messaging services and push over cellular services are presented. For each services the figuration of their architecture and the basic definition of their main entities are shown. Moreover, the graphical diagrams of SIP signalization are depicted for these services. In the next chapter, the self implementation of services was designed, namely presence services and services for speech transmission with next secondary function as sending email with registration information of user. The project was designed as client - server application in the development studio SDS Ericsson 4.1. The client application was simulated as java application and also as an application for Symbian emulator. The process of client registration was performed with the help of ICP platform. Finally, the diagram of analysis communication client - server is displayed with the captured packets explanation by the help of network analyzer WireShark. The video files, which were specially created for this thesis showing presentations for presence services and sending email. The most important results are summarized in the end of this article.
267

Multimediální služby založené na IMS / IMS based multimedia services

Novotný, Roman January 2010 (has links)
Submitted work describes IMS (IP Multimedia Subsystem) and focuses on services offered by this technology. In the theoretical part of the thesis is a detailed description of the IMS architecture, in the terms of its components and interfaces. Also a SIP protocol is described as the main signalling protocol, which represents the basis of the IMS architecture and RTP protocol that allows the transmission of multimedia data in real-time. Further, there are provided services that the IMS system brings. The practical part of the work describes the design and implementation of services within the IMS. It is a client-server service. Server part of the system is implemented as a SIP Servlet application. It has access to the MySQL database, which stores records of multimedia files. Client registered in the IMS network can communicate with the SIP servlet sending a request for information on such files. Following this communication, the client can play the file in his online ICP application, or download it into his PC and then play. To play and view multimedia fines is used JMF. The service is implemented in a development environment SDS Ericsson 4.1, which allows simulation of the IMS network.
268

Sledování migrace vybraných kovů z obalů pro nápoje / Study of the migration of selected metals from beverages packaging

Šťávová, Elena January 2016 (has links)
This master’s thesis follows on bachelor’s thesis and deals with study of migration of aluminium and tin from metal containers. Manufactory of metal containers, corrosion of cans, chemical behaviour of aluminium and tin in food, its effects on health and possibilities of the determination in food and characterization of inductively coupled plasma optical emission spectrometry (ICP-OES) are described in theoretical part. In experimental part 30 different beverages in cans and glass and 6 tomato purees purchased at common stores were analysed. Measured concentrations of aluminium in beverages from cans and from glass containers were compared. It was found that beverages from cans didn’t contain higher concentrations of aluminium than beverages from glass containers. This could be caused by the fact that the aluminium is very stable metal, it has high corrosive endurance and therefore is very suitable for food packaging. Measured concentrations of tin in tomato purees were compared with the maximum permissible level of tin in canned food determined by European legislation. None of them exceed the 200 mg/kg level. All of the measured concentrations were very low, because all of the cans contained protective layer of lacquer, which gives protection against corrosion and also effectively protects from releasing of tin into the can content.
269

Building a Database with Background Equivalent Concentrations to Predict Spectral Overlaps in ICP-MS

Liu, Fang 18 May 2017 (has links)
No description available.
270

Development of laser micro-sampling and electrothermal vaporization techniques for ICP-mass spectrometry and its cosmochemical implications on opaque assemblages in chondrites / ICP質量分析法を用いた微量元素同位体分析に向けたレーザー局所サンプリング法および電気加熱気化法の開発とその宇宙化学物質への応用

Okabayashi, Satoki 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18086号 / 理博第3964号 / 新制||理||1571(附属図書館) / 30944 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 平田 岳史, 教授 田上 高広, 准教授 三宅 亮 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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