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Tribotechnická diagnostika prvonáplní motorového oleje z motorů osobních automobilů
Prokeš, David
The master thesis Tribotechnical diagnostics of first-fill engine oil from passenger car engines deals with the composition, production, distribution, wear and tear, specification of passenger car engine oils and their diagnostics and evaluation during use and wear. The research part of the thesis deals with the classification of lubricants and their brief description, classification of engine oils and a brief description of their manufacture. Subsequently, the basic concepts related to the above topic are described. The experimental part of the thesis deals with the methodology, material and actual measurement of selected parameters for the assessment of engine oil condition during engine break-in of new passenger cars. The selected indicators are the amount and morphology of particles, determination of the water content of engine oil, alkaline reserve, oxidation and additive content. The following diagnosis of the condition of the primary engine oil confirmed the assumption of a higher content of wear metals. An interesting result was the detection of higher oxidation rates in engine oils, which may be a consequence of long storage periods before the car is sold.
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Polyethylene wear particles around joint replacements - their properties, distribution and possible mechanism of their adverse biological effects
Zolotarevová, Eva ; Gallo, Jiří (advisor) ; Rauch, Pavel (referee) ; Horák, Zdeněk (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE DEPARTMENT OF BIOCHEMISTRY PRAGUE 2010 Supervisor: Doc. MUDr. Jiří Gallo, PhD. Supervisor-consultant: Prof. RNDr. Gustav Entlicher, CSc. Eva Zolotarevová Summary of PhD Thesis POLYETHYLENE WEAR PARTICLES AROUND TOTAL JOINT REPLACEMENTS - THEIR PROPERTIES, DISTRIBUTION AND POSSIBLE MECHANISM OF THEIR ADVERSE BIOLOGICAL EFFECTS PRAGUE 2010 The research project was supported by the Grant project of National research program II. (no. 2B06096) of the Czech Ministry of Education, Youth and Sports named "Observation and minimization of UHMWPE wear in joint replacements". Front-page picture: Polyethylene wear particle isolated from granuloma tissue surrounding total hip replacement; Electron microscope microphotograph; particle size app. 90 x 80 µm; retouched Eva Zolotarevová Introduction Introduction For many people all over the world a replacement with an implant of irreversibly damaged joint is often the only way how to come back to normal life without pain and mobility limitation. Nowadays, greater and greater requirements are asked of quality of all replacement components, especially in terms of quality of used materials. Biomechanical properties of hip and knee replacements have been already solved. The most often used materials for manufacturing joint...
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Polyethylene wear particles around joint replacements - their properties, distribution and possible mechanism of their adverse biological effects
Zolotarevová, Eva
This PhD thesis in essence rounds off the range of queries asked several years ago when the task was set by Doc. RNDr. Zdenek Horak, PhD. The original isolation procedure for polyethylene wear particles, identification of some of their physico-chemical properties and manipulation accordingly has been successful in the process of this thesis accomplishment. It became possible to quantify the particles at relative as well as absolute scale. The thesis managed to disprove the published opinion that centrifugation can affect the morphology of isolated particles. The issue of distribution of polyethylene wear particles around hip endoprothesis has been solved at two levels: "macroscopically", the distribution of wear particles in zones around endoprosthesis was showed (this thesis does not include these data). Furthermore, at the "microscopic" level, the distribution of wear particles in granuloma tissue from the zones surrounding endoprostheses with most particles has been determined. The granuloma tissue formed in zones with most particles because of that. It was observed that the common term - osteoagressive granuloma - used by orthopedist is rather misguided. Granuloma is not aggressive to bone tissue. On the contrary, the granuloma formation reduces the effective amount of wear particles with...
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Průběžné sledování degradace motorového oleje ve sklízecí mlátičce
Dvořák, Martin
This thesis deals with description of engine oils in diesel combustion engine of combine harvester. First part contains basic properties of engine oils and their production. Other chapters include classification of oil and also the issue of abrasion particles in the engine. Practical part contain summary of engine oil from combine harvester Case IH AFX 9120. For comparison was sampled new oil. Other samples were taken during machine operation every 50 Eh until of the service interval of 300 Eh. The thesis also describes the methodology of measurement process measuring device for evaluation of the content abrasion particles, density, dynamic and kinematic viscosity and skid tension. The results are processed into a graph and from the results obtained was determined actual state of degradation of engine oil.
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Degradace motorového oleje ve sklízecí mlátičce
Halenka, Milan
This Master's thesis focuses on the problematics of the diesel engine oil in the combine harvesters degradation. The first part focuses on the manufacturing process of the en-gine oils, on their structure, on the description of their properties and on their division into individual classifications. Types of the lubrication systems and the diagnostics of the engine oils are described next. Seven samples of oil were monitored, three of them were samples of used engine oil from the combine harvesters Claas, where the engine oil with viscosity grade 10W-40 was used. Next two samples were from used oil from the combine harvesters Case IH, where was the engine oil with viscosity grade 15W-40. Two samples of new oil of each kind were taken for the comparison of the engine oil degradation. Their physical and mechanical properties were compared afterwards. The results obtained are interpreted both numerically and graphically. In the conclusion, the evaluation and the results obtained are summarized.
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Degradace motorového oleje v zahradní technice
Burian, Martin
The diploma thesis deals with the problematics of engine oils degradation in a garden machinery. In the theoretical part, there is a description of the basic functions and properties of engine oils, their production, composition and also used standard classifications. The practical part is devoted to evaluation of the degradation of five selected engine oils. There are described the oils, the selected garden machinery (five machines with a four-stroke spark-ignition engine) and also the sampling methodology and measuring devices. Two samples of oil were taken from each machine – a partially used and a used engine oil, which were compared with a new oil of the same specification and designation. For all samples, their dynamic viscosity (at 40 °C), density and amount of selected metal wear particles were measured. In the final chapter, the measured parameters are processed into a tables and graphs, and the results are discussed.
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Degradace motorového oleje ve vznětovém motoru osobního automobilu
Oral, Martin
The thesis is focused on the problems of degradation of engine oils of the same viscosity class 5W-30.The first part of the thesis is describing lubricating systems and their component parts. The thesis also focuses on the division of oil in each classification and description of its properties. Samples of the oil have been taken from two cars with identical diesel engine, but with different total traveling distance. Attention is paid to the amount of structural metals, contaminants and additives in both oils, and throughout the oil usage interval. The results are interpreted graphically and various dependencies are modeled using appropriate regression functions. Thesis compares the mechanical and physical properties of engine oils, depending on mileage. The conclusion summarizes the evaluation and the results obtained.
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Polyethylene wear particles around joint replacements - their properties, distribution and possible mechanism of their adverse biological effects
Zolotarevová, Eva
This PhD thesis in essence rounds off the range of queries asked several years ago when the task was set by Doc. RNDr. Zdenek Horak, PhD. The original isolation procedure for polyethylene wear particles, identification of some of their physico-chemical properties and manipulation accordingly has been successful in the process of this thesis accomplishment. It became possible to quantify the particles at relative as well as absolute scale. The thesis managed to disprove the published opinion that centrifugation can affect the morphology of isolated particles. The issue of distribution of polyethylene wear particles around hip endoprothesis has been solved at two levels: "macroscopically", the distribution of wear particles in zones around endoprosthesis was showed (this thesis does not include these data). Furthermore, at the "microscopic" level, the distribution of wear particles in granuloma tissue from the zones surrounding endoprostheses with most particles has been determined. The granuloma tissue formed in zones with most particles because of that. It was observed that the common term - osteoagressive granuloma - used by orthopedist is rather misguided. Granuloma is not aggressive to bone tissue. On the contrary, the granuloma formation reduces the effective amount of wear particles with...
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Polyethylene wear particles around joint replacements - their properties, distribution and possible mechanism of their adverse biological effects
Zolotarevová, Eva ; Gallo, Jiří (advisor) ; Rauch, Pavel (referee) ; Horák, Zdeněk (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE DEPARTMENT OF BIOCHEMISTRY PRAGUE 2010 Supervisor: Doc. MUDr. Jiří Gallo, PhD. Supervisor-consultant: Prof. RNDr. Gustav Entlicher, CSc. Eva Zolotarevová Summary of PhD Thesis POLYETHYLENE WEAR PARTICLES AROUND TOTAL JOINT REPLACEMENTS - THEIR PROPERTIES, DISTRIBUTION AND POSSIBLE MECHANISM OF THEIR ADVERSE BIOLOGICAL EFFECTS PRAGUE 2010 The research project was supported by the Grant project of National research program II. (no. 2B06096) of the Czech Ministry of Education, Youth and Sports named "Observation and minimization of UHMWPE wear in joint replacements". Front-page picture: Polyethylene wear particle isolated from granuloma tissue surrounding total hip replacement; Electron microscope microphotograph; particle size app. 90 x 80 µm; retouched Eva Zolotarevová Introduction Introduction For many people all over the world a replacement with an implant of irreversibly damaged joint is often the only way how to come back to normal life without pain and mobility limitation. Nowadays, greater and greater requirements are asked of quality of all replacement components, especially in terms of quality of used materials. Biomechanical properties of hip and knee replacements have been already solved. The most often used materials for manufacturing joint...
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