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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.
1

Experimental Investigation of the Air Release in Hydraulic Reservoirs

Longhitano, Marco, Protase, Alessandro, Murrenhoff, Hubertus 28 April 2016 (has links) (PDF)
Air contamination strongly decreases the efficiency of fluid power systems and when the allowable limits are exceeded, the performance of the system deteriorates. The hydraulic reservoir performs the function of releasing the entrained air of the hydraulic system to the surroundings. In recent years, the reservoir design has become an important task in the design of the hydraulic system due to space restrictions forcing the use of small sized reservoirs. Despite this fact, experimental results on an air release are not available. In this paper, an experimental investigation of the air release in hydraulic reservoirs is presented. A test apparatus using an optical method as well as the post-processing of the results is described. These are given in terms of an air release rate for different reservoir designs over a wide range of oil flow rates and air loads. The current study is a significant step forward in the design of fluid power systems, as it provides an experimental procedure to measure the air release in the hydraulic reservoir as well as its quantitative analysis.
2

Implementace algoritmu pro měření parametrů energetických materiálů v obvodu FPGA / Implementation of algorithm for energetic material measurement in FPGA device

Slovák, Jiří January 2014 (has links)
In the text of the master´s thesis, it is at first briefly referred about Energetic Material Measurement topic in general. Emphasis is placed especially at the description of the Velocity of Detonation and short analysis of selected measurement method. The most significant part of the paper is dedicated to the design and description of the system that was created in ISE Design Suite environment using VHDL language. The development was performed with respect to oncoming integration into the board with FPGA and A/D converters. The operation of detection algorithm which was created based on the MATLAB model was verified in the final part of the thesis by simulation of processing of real optical probe signals.
3

Experimental Investigation of the Air Release in Hydraulic Reservoirs

Longhitano, Marco, Protase, Alessandro, Murrenhoff, Hubertus January 2016 (has links)
Air contamination strongly decreases the efficiency of fluid power systems and when the allowable limits are exceeded, the performance of the system deteriorates. The hydraulic reservoir performs the function of releasing the entrained air of the hydraulic system to the surroundings. In recent years, the reservoir design has become an important task in the design of the hydraulic system due to space restrictions forcing the use of small sized reservoirs. Despite this fact, experimental results on an air release are not available. In this paper, an experimental investigation of the air release in hydraulic reservoirs is presented. A test apparatus using an optical method as well as the post-processing of the results is described. These are given in terms of an air release rate for different reservoir designs over a wide range of oil flow rates and air loads. The current study is a significant step forward in the design of fluid power systems, as it provides an experimental procedure to measure the air release in the hydraulic reservoir as well as its quantitative analysis.
4

Estudos da influência de surfactantes e determinação de cloro em água potável empregando-se TCPO e 2-NPO / Studies of the influence of surfactants and determination of chlorine in drinking water using TCPO and 2-NPO

Matsuda, Margareth Mie Nakamura 16 September 2003 (has links)
As reações quimiluminescentes de oxalato de bis(2,4,6-triclorofenila) (TCPO) e oxalato de bis(2-nitrofenila) (2-NPO), com f1uoranteno como f1uoróforo, em sistemas micelares aquosos, foram estudadas na presença de alguns surfactantes. A oxidação destes oxalatos por peróxido de hidrogênio ou por hidroperóxido de t - butila produz quimiluminescência cuja intensidade depende da acidez e da presença de imidazol. A intensidade de quimiluminescência é maior na presença de alguns surfactantes, especialmente CTAC, OTAC, DDAB, DODAC e β-ciclodextrina. A reação de TCPO com cloro (HCIO, CIO- e Cl2) na presença de 9,10-difenilantraceno como fluoróforo, em meio de acetonitrila/água, também foi investigada. Um sistema de análise por injeção em fluxo para determinação de cloro com aplicação analítica em água de torneira foi desenvolvido. A faixa linear para a curva analítica de cloro e o limite de detecção foram, respectivamente: (0,2 - 3,0)x10-5 e 0,2 x10-5 mol L-1. / The chemiluminescent reactions of bis (2,4,6-trichlorophenyl) oxalate (TCPO) and bis(2-nitrophenyl) oxalate (2-NPO), with fluoranthene as fluorophore, in aqueous micellar systems, were studied in the presence of surfactants. The oxidation of these oxalates by hydrogen peroxide or t-butyl peroxide produces chemiluminescence, which depends on the acidity and imidazole presence. The chemiluminescent intensity is higher in the presence of some surfactants, especially CTAC, OTAC, DDAB, DODAC and β-cyclodextrine. The reaction of TCPO with free chlorine (HCIO, CIO- and Cl2), in the presence of 9,10-diphenylanthracene as fluorophore in acetonitrile/water medium, was also investigated. A flow injection analysis system, for free chlorine determination with analytical application in tap water was developed. The linear range for free chlorine and detection limit were, respectively: (0.2-3.0)x10-5 and 0.2x10-5 mol L-1.
5

Estudos da influência de surfactantes e determinação de cloro em água potável empregando-se TCPO e 2-NPO / Studies of the influence of surfactants and determination of chlorine in drinking water using TCPO and 2-NPO

Margareth Mie Nakamura Matsuda 16 September 2003 (has links)
As reações quimiluminescentes de oxalato de bis(2,4,6-triclorofenila) (TCPO) e oxalato de bis(2-nitrofenila) (2-NPO), com f1uoranteno como f1uoróforo, em sistemas micelares aquosos, foram estudadas na presença de alguns surfactantes. A oxidação destes oxalatos por peróxido de hidrogênio ou por hidroperóxido de t - butila produz quimiluminescência cuja intensidade depende da acidez e da presença de imidazol. A intensidade de quimiluminescência é maior na presença de alguns surfactantes, especialmente CTAC, OTAC, DDAB, DODAC e β-ciclodextrina. A reação de TCPO com cloro (HCIO, CIO- e Cl2) na presença de 9,10-difenilantraceno como fluoróforo, em meio de acetonitrila/água, também foi investigada. Um sistema de análise por injeção em fluxo para determinação de cloro com aplicação analítica em água de torneira foi desenvolvido. A faixa linear para a curva analítica de cloro e o limite de detecção foram, respectivamente: (0,2 - 3,0)x10-5 e 0,2 x10-5 mol L-1. / The chemiluminescent reactions of bis (2,4,6-trichlorophenyl) oxalate (TCPO) and bis(2-nitrophenyl) oxalate (2-NPO), with fluoranthene as fluorophore, in aqueous micellar systems, were studied in the presence of surfactants. The oxidation of these oxalates by hydrogen peroxide or t-butyl peroxide produces chemiluminescence, which depends on the acidity and imidazole presence. The chemiluminescent intensity is higher in the presence of some surfactants, especially CTAC, OTAC, DDAB, DODAC and β-cyclodextrine. The reaction of TCPO with free chlorine (HCIO, CIO- and Cl2), in the presence of 9,10-diphenylanthracene as fluorophore in acetonitrile/water medium, was also investigated. A flow injection analysis system, for free chlorine determination with analytical application in tap water was developed. The linear range for free chlorine and detection limit were, respectively: (0.2-3.0)x10-5 and 0.2x10-5 mol L-1.
6

Analýza elektrických biologických signálů v experimentální kardiologii / Analysis of Biosignals in Cardiovascular Research

Janoušek, Oto January 2013 (has links)
The new approach for motion artifact suppression in optical action potential records is presented in this thesis. Presented approach is based on independent component analysis utilization. Efficiency of proposed approach is evaluated here as well as its comparison with state of the art motion artifact suppression approaches.
7

Estudo da autoxidação de [Ni(cyclam)]2+ induzida por óxidos de S(IV) / Study autoxidation [Ni(cyclam)]2+ induced by oxide S(IV)

Pezza, Helena Redigolo 12 March 1997 (has links)
A autoxidação de [Ni(cyclam)]2+ (cyclam = 1,4,8,11-tetraazociclotetradecano) induzida por S(IV) foi estudada acompanhando-se espectrofotometricamente, em função do tempo, a formação de [Ni(cyclam)]3+ em soluções saturadas com oxigênio contendo: [Ni(cyclam)]2+ 6,0 x10-3 mol L-1, [Ni(cyclam)]3+ (inicial) 8,0x10-6 mol L-1, cyclam 6,0x10-3 mol L-1, S(IV) (1,0 - 5,0)x10-4 mol L-1 e HClO4 1,0 mol L-1 a T = 25,0 °C e força iônica 1,0 mol L-1. A reação de autoxidação exibe um comportamento autocatalítico no qual o período de indução depende da concentração inicial de Ni(III). O estudo cinético da redução de Ni(III) por S(IV), sob condições anaeróbicas, e a autoxidação de Ni(II) mostraram que a etapa determinante da velocidade da reação é a redução de Ni(III) por S(IV) para produzir o radical SO3•-, que reage com o oxigênio dissolvido produzindo SO5•- o qual rapidamente reoxida o Ni(II). Os resultados mostram claramente um ciclo redox que depende do balanço entre a concentração de S(IV) e oxigênio. Quando a reação se processa na presença de Co(III) (10-6 a 10-4 mol L-1) e de Mn(II) (10-3 a 10-2 mol L-1) constatou-se a ocorrência de efeito sinérgico positivo na formação de [Ni(cyclam)]3+. / The autoxidation of [Ni(cyclam)]2+, cyclam = 1,4,8,11-tetraazacyclotetradecane, accelerated by sulfur dioxide was studied by spectrophotometrically monitoring the formation of [Ni(cyclam)3+ under the conditions: [Ni(cyclam)]2+ = 6.0 x 10-3 mol L-1; initial [Ni(cyclam)]3+ = 8.0 x 10-6 mol L-1; [cyclam] = 6.0 x 10-3 mol L-1 ; [S(IV)] = (1.0 - 5.0) x10-4 mol L-1 and 1.0 mol L-1 perchloric acid in oxygen saturated solutions at 25.0 °C and ionic strength 1.0 mol L-1. The autoxidation reaction exhibits an autocatalytic behavior in which the induction period depends on the initial Ni(III) concentration. The kinetic study of the reduction of Ni(III) by S(IV), under anaerobic conditions, and autoxidation of Ni(II) showed as the rate-determining step the reduction of Ni(III) by S(IV) to produce SO3•- radical, which reacts with dissolved oxygen to produce SO5•- and rapidly oxidizes Ni(II). The results clearly show a redox cycling process which depends on the balance of S(IV) and oxygen concentration. The sinergystic effect of the Co(III) and Mn(II) was studied. Both exhibit a positive synergistic effect in the sulfite-induced aLrtoxidation of Ni(II).
8

Estudo da autoxidação de [Ni(cyclam)]2+ induzida por óxidos de S(IV) / Study autoxidation [Ni(cyclam)]2+ induced by oxide S(IV)

Helena Redigolo Pezza 12 March 1997 (has links)
A autoxidação de [Ni(cyclam)]2+ (cyclam = 1,4,8,11-tetraazociclotetradecano) induzida por S(IV) foi estudada acompanhando-se espectrofotometricamente, em função do tempo, a formação de [Ni(cyclam)]3+ em soluções saturadas com oxigênio contendo: [Ni(cyclam)]2+ 6,0 x10-3 mol L-1, [Ni(cyclam)]3+ (inicial) 8,0x10-6 mol L-1, cyclam 6,0x10-3 mol L-1, S(IV) (1,0 - 5,0)x10-4 mol L-1 e HClO4 1,0 mol L-1 a T = 25,0 °C e força iônica 1,0 mol L-1. A reação de autoxidação exibe um comportamento autocatalítico no qual o período de indução depende da concentração inicial de Ni(III). O estudo cinético da redução de Ni(III) por S(IV), sob condições anaeróbicas, e a autoxidação de Ni(II) mostraram que a etapa determinante da velocidade da reação é a redução de Ni(III) por S(IV) para produzir o radical SO3•-, que reage com o oxigênio dissolvido produzindo SO5•- o qual rapidamente reoxida o Ni(II). Os resultados mostram claramente um ciclo redox que depende do balanço entre a concentração de S(IV) e oxigênio. Quando a reação se processa na presença de Co(III) (10-6 a 10-4 mol L-1) e de Mn(II) (10-3 a 10-2 mol L-1) constatou-se a ocorrência de efeito sinérgico positivo na formação de [Ni(cyclam)]3+. / The autoxidation of [Ni(cyclam)]2+, cyclam = 1,4,8,11-tetraazacyclotetradecane, accelerated by sulfur dioxide was studied by spectrophotometrically monitoring the formation of [Ni(cyclam)3+ under the conditions: [Ni(cyclam)]2+ = 6.0 x 10-3 mol L-1; initial [Ni(cyclam)]3+ = 8.0 x 10-6 mol L-1; [cyclam] = 6.0 x 10-3 mol L-1 ; [S(IV)] = (1.0 - 5.0) x10-4 mol L-1 and 1.0 mol L-1 perchloric acid in oxygen saturated solutions at 25.0 °C and ionic strength 1.0 mol L-1. The autoxidation reaction exhibits an autocatalytic behavior in which the induction period depends on the initial Ni(III) concentration. The kinetic study of the reduction of Ni(III) by S(IV), under anaerobic conditions, and autoxidation of Ni(II) showed as the rate-determining step the reduction of Ni(III) by S(IV) to produce SO3•- radical, which reacts with dissolved oxygen to produce SO5•- and rapidly oxidizes Ni(II). The results clearly show a redox cycling process which depends on the balance of S(IV) and oxygen concentration. The sinergystic effect of the Co(III) and Mn(II) was studied. Both exhibit a positive synergistic effect in the sulfite-induced aLrtoxidation of Ni(II).
9

Borne in Fire - A Study of Black Carbon Emitted from Coal Fired Power Plants in West Bengal, India.

Hendricks, Ra'eesah January 2023 (has links)
Black carbon has been reported to have major impacts on climate, environmental quality, and health. A chemothermal oxidation method, ordinarily used to isolate black carbon from soils, sediments and aquatic samples was applied to explore atmospheric samples. The results were then compared with thermal optical reflectance measurements, and then investigated in parallel with a health survey conducted during sampling. This study assesses atmospheric emissions from the NTPC Farakka coal-fired power plant in West Bengal, the distribution of emissions, the mobilization of black carbon, and its impact on pulmonary and cardiovascular conditions among respondents in Murshidabad and Malda, in West Bengal, India. Two measurement campaigns were conducted during winter and summer (November 2021 – June 2022); a total of 81 samples (Murshidabad) and 65 samples (Malda) were collected and analyzed and 193 respondents were surveyed for lung functionality. Over the study period, the mean concentration of PM2.5 and soot were observed to be 147 μg/m³; 113 μg/m³ and 1.52 μg/m³; 1.54 μg/m³ respectively. From the spirometry tests, it was concluded that there was chronic exposure to PM2.5 at both the sites, during the winter and monsoon campaigns. With increases in PM2.5 corresponding with higher numbers of restrictive and obstructive cases.
10

Návrh a realizace experimentálního zařízení pro určování zbytkové napjatosti ohýbaných vzorků / Design and realization of experimental equipment for determination of residual stress of bent samples

Novotný, Lukáš January 2018 (has links)
The master thesis is focused to design and realization of experimental equipment for researching of residual stress determination for specimen with non-uniform distribution stress along the depth. Literature search study of problematic was performed and it was used for elaboration of chapters about origin of residual stress, their classification and chapters about methods, which are used for measuring of residual stress and their determination. The following part explains the design of experimental equipment and stress-strain analysis of selected parts of this equipment. Then the final design of equipment is presented, including complete production drawings, and it’s explained final assembling of experimental equipment. Final chapter is devoted to examinable loading of specimen.

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