Evaluation of an inspection program and overhauls for ZLIN 26 aircraft

Bakalářská práce pojednává o způsobu provádění periodických prohlídek a oprav letounů ZLIN řady Z 26. Již z názvu této práce vyplývá, že jde o problematiku náročnou a velmi obsáhlou. Mým cílem tedy bylo přiblížit vybrané oblasti týkající se údržby daných letounů a navrhnout změny některých stávajících postupů údržby. V úvodu práce se krátce seznámíme s historií letounů ZLIN a jednotlivými typy z řady Z 226. V textu jsou dále uvedeny typy prohlídek, kterými během své životnosti letouny prochází. Postupy prohlídek a generálních oprav jsou detailně popsány a pro správnou představu také doplněny ilustracemi nebo fotografiemi. Následující kapitola se věnuje zhodnocení stávajících postupů aplikovaných při prohlídkách či generálních opravách letounu. Jejich optimalizaci se věnuje čtvrtá kapitola, ve které jsou navrženy možné úpravy těchto postupů. V poslední, páté kapitole, se práce věnuje možnostem prodloužení životnosti letounů ZLIN, která je v poslední době diskutována zejména s ohledem na fakt, že některé letouny této typové řady již dosáhly základního limitu stanovené životnosti, aniž by se vyskytovala vážná únavová poškození primární konstrukce draku.This bachelor´s thesis deals with ZLIN Z 26 Series Aircraft maintenance and repairs procedures. Even the name shows, that this theme is very demanding and extensive. My interest was to explain some maintenance procedures of these aircraft and offer changes of it. In the beginning of this thesis we can briefly learn history of the ZLIN Aircraft and particular Z 226 Series models. There are mentioned difference maintenance procedures, applicable on the planes thru the service life time. Inspection and overhaul procedures are described in details and for better understanding were attached drawings or photos. Following chapter deals with evaluation existing inspections and overhauls - maintenance – procedures. Optimization of the maintenance is part of the chapter fourth, where is described possible innovation of the maintenance check list. In the last, fifth chapter, of this thesis are mentioned possibilities of the ZLIN Aircraft life time prolongation, which is actually discussed because of some aircraft of this type series reached basic life time limit, without any serious fatigue airframe damages appears.

Safe-life extension program for ZLIN Z 126 and 226 airplanes

Diplomová práce pojednává o možnostech prodloužení životnosti letounů ZLIN Z 126 a 226, které jsou i přes své stáří a dávno ukončenou výrobu stále oblíbené a rozšířené nejen v České republice. Se stářím těchto strojů souvisí také fakt, že některé letouny se již nezadržitelně blíží své hranici životnosti a sílí tak zájem po jejich co nejdelší době letuschopnosti, jak po technické, tak legislativní stránce. Jak již bylo zmíněno v mé bakalářské práci, v průběhu existence této modelové řady nebyla zjištěna žádná zásadní provozní poškození s výjimkou sporadické vrstevnaté koroze pásnic křídla. Praxe s údržbou těchto letounu tak poukazuje na jisté podhodnocení současného limitu až 5500 letových hodin a je tedy nasnadě navrhnout možný postup pro zvýšení současného limitu. V diplomové práci je tedy v této souvislosti uvažována možnost výroby nových pásnic křídel z jiného materiálu, provedený únavový výpočet pro křídlo s vyměněnými pásnicemi a navržen technologický postup této výměny tak, aby letouny ZLIN Z 126 a 226 mohly být bezpečně provozovány i nadále.This master's thesis discusses the possibilities of safe-life extension program for ZLIN Z 126 and 226 airplanes, which despite their age and long-end production are still widespread and popular not only in the Czech Republic. The age of these aircraft is also related to the fact, that some aircraft are already approaching its border life, so there is an interest for the longest possible technical and legislative airworthiness. As mentioned in my bachelor's thesis, during the existence of this model series, there was no major damage occurred, except for sporadic exfoliation corrosion of wing flanges. Experience with maintenance of this aircraft points to certain underestimation of the current 5500hrs lifetime and it is obvious to suggest possible steps to increase the current limit. The thesis is therefore considered in this context the possibility of producing new wing flanges made of another material, performed the calculation for wing fatigue exchanged with flanges and designed technological process of this exchange, so that ZLIN Z 126 and 226 airplanes can be safely operated in the future.

The issue of evaluating the production of pollutants in the exhaust gases of passenger cars

Práce rozebírá hodnocení homologačního měření produkce škodlivin osobních automobilů v Evropské unii. Chronologicky jsou popsány používané metodiky měření, včetně norem, které je popisují. Spolu s vylepšeními a nedostatky, které s sebou nové požadavky přinesly, je zmíněn i dopad na nové automobily a trendy, které emisní požadavky ovlivnily v oblasti vývoje automobilu. Hlavní část práce se zabývá měřením emisí ve skutečném provozu RDE a popisuje problematiku této přelomové metodiky.This thesis analyses evaluation of homologation measurment of pollutant production of passenger car in the European union. The measurement methodologies used are described chronologically, including the standarts that describe them. Along with the improvements and disadvantages that the new requirements have brought, it also deals with the impact on new cars and the trends that have affected emisson requirements in the field of car development. The main part of the work deals with the measurement of real driving emissions RDE and describes the issue of this breakthrough methodology.

Detection of mixed fields of neutron and photon radiation using 3He and new scintillation materials

The poster includes experimental measurements with 3He and the latest scintillation materials EJ-299-33 in fields of neutron and photon radiation using modern electronics which we designed. Electronic part of the measuring system is built on recently developed AD converter with very high sampling frequency (1 GHz). In the theoretical part, the Monte Carlo simulations of response characteristics of the measured scintillation materials are presented.Poster obsahuje experimentální měření za požití He-3 a nejnovějšího scintilačního materiálu EJ-299-33 v polích neutronů a fotonů. Elektronická část je postavena na základě velmi rychlých AD převodnků (1 GHz). V teoretické části je popsána Monte Carlo simulace odezvové matice použitých detektorů.The poster includes experimental measurements with 3He and the latest scintillation materials EJ-299-33 in fields of neutron and photon radiation using modern electronics which we designed. Electronic part of the measuring system is built on recently developed AD converter with very high sampling frequency (1 GHz). In the theoretical part, the Monte Carlo simulations of response characteristics of the measured scintillation materials are presented

Characterization of the Graphite Pile as a Source of Thermal Neutrons

The absorption cross sections of low energy neutrons obey 1/v law for most materials. Therefore, the detection efficiency of a particular detector increase with decreasing neutron energy. Consequently, most of neutron measuring instruments consist of the detector of thermal neutrons which is located inside of the polyethylene moderator. Development of such instruments requires testing and response calibrations in the field of thermal neutrons. Availability of thermal neutron beams on nuclear reactors is limited and access to them is rather complicated, so it is more convenient to moderate neutrons from the radionuclide neutron sources. Since radionuclide neutron sources are producing fast neutrons it is necessary to use an appropriate moderator material like heavy water or graphite to thermalize neutrons from the source and to avoid thermal neutron capture in the same time.The absorption cross sections of low energy neutrons obey 1/v law for most materials. Therefore, the detection efficiency of a particular detector increase with decreasing neutron energy. Consequently, most of neutron measuring instruments consist of the detector of thermal neutrons which is located inside of the polyethylene moderator. Development of such instruments requires testing and response calibrations in the field of thermal neutrons. Availability of thermal neutron beams on nuclear reactors is limited and access to them is rather complicated, so it is more convenient to moderate neutrons from the radionuclide neutron sources. Since radionuclide neutron sources are producing fast neutrons it is necessary to use an appropriate moderator material like heavy water or graphite to thermalize neutrons from the source and to avoid thermal neutron capture in the same time

Green synthesis and the stablization of selenium nanoparticles using carboxylmethyl starch

The growing interest in biodegradable products paves the way for the safest sustainable earth. Starch is an extensively studied, cost-effective, easily accessible, and highly trusted resource to produce biodegradable products in the present and future. However, the exploitation of these starch in several fields requires substantial changes in its chemical functionalities and related properties. Here, we investigated the conditions (pH, temperature, the concentration of starch, concentration of chloroacetate, time, the ratio between starch/sodium hydroxide, etc.) that affect the preparation of carboxymethyl starch (CMS). The chemical structure and degree of substitution of native starch and CMS were confirmed by Fourier transform infrared ( FTIR), X-ray powder diffraction (XRD), Thermogravimetric analysis (TGA), potentiometric titration, Scanning electron microscope (SEM), and Nuclear magnetic resonance spectroscopy (NMR ). CMS's rheological properties show that CMS's intrinsic viscosity increased with increased degrees of substitutions (DS) from CMS (0.05 to 0.45). The CMS with different DS (0.05 to 0.45) was used for the first time to stabilize selenium nanoparticles (Se-NPs), showing spherical shape with a high homogenous size of Se-NPs (approx. 50 nm). The NPs shape and size stability were investigated and confirmed by different techniques like Dynamic light scanning (DLS), SEM, and Transmission electron microscope (TEM

The Effect of Network Solvation on the Viscoelastic Response of Polymer Hydrogels

The majority of investigations consider the deformation response of hydrogels, fully controlled by the deformation behavior of their polymer network, neglecting the contribution caused by the presence of water. Here, we use molecular dynamics simulation in an attempt to include the effect of physically bound water via polymer chain solvation on the viscoelastic response of hydrogels. Our model allows us to control the solvation of chains as an independent variable. The solvation of the chain is independent of other factors, mainly the effect (pH) which interferes significantly in experiments. The solvation of hydrophilic chains was controlled by setting a partial charge on the chains and quantified by the Bjerrum length (BL). The BL was calculated from the partial electric charge of the solvent and macromolecular network. When the BL is short, the repulsive Van der Waals interactions are predominant in the vicinity of macromolecules and solvation is not observed. For a long BL, the water molecules in the solvation zone of network are in the same range as attractive intermolecular forces and the solvation occurs. The model also allows the consideration of molecules of water attached to two chains simultaneously, forming a temporary bridging. By elucidating the relations between solvation of the network and structural changes during the network deformation, one may predict the viscoelastic properties of hydrogels knowing the molecular structure of its polymer chains

A role of reductones in the monitoring of sulphur dioxide content in wines during their maturation and storage

The content of free SO2 (1.3-37.9 mg/l and 5.3-19.7 mg/l for 2009 and 2010) and total SO2 (38.3-272.0 mg/l and 52.0-102.1 mg/l for 2009 and 2010) for individual wines was in a broad interval. Results of free SO2 found using the commercial SO2 reagent were higher than our results since the reagent determined not only free SO2 but also reductones. The content of titrated acids was constant with a very moderate time decrease and the values were on average about 9.1-5.3 g/l (2009) and 13.1-7.9 g/l (2010). Similarly, the content of tartaric acid was nearly constant and the values were on average about 2.37-1.47 g/l (2009) and 6.65-2.69 g/l (2010). The percentage ratio of tartaric acid in the content of titrated acids is also constant (average 24.39%-38.6% for individual wines).Eurostars.program [WINEurope E! 4230