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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

A new calorimetry design for assessing proposed technologies in low energy power production

Alexandridis, Alexandros 12 1900 (has links)
As a method to measure heat sources for various mechanical, electrical and chemical processes, calorimeters have been used for many years. This project was conducted to develop, build, test and measure heat production with a Novel Calorimeter designed to detect excess heat for various processes. An energy balance analysis was conducted by restricting the change in input heat and output to near zero. The work term was also held near zero and attempts were made to make the response independent of steam quality. The data and results suggest that the calorimeter was able to run continuously and achieve close to ambient temperatures under adjusted flow rates. Suggestions are proposed to improve the design of the Novel Calorimeter.
2

The production and characterisation of scintillating fluoride glasses

McKinlay, Karen J. January 1999 (has links)
No description available.
3

Spatial reconstruction of electrons with an accordion geometry electromagnetic calorimeter

White, John Stephen 07 December 2011 (has links)
Graduate
4

The heats of formation of zirconium hafnium and niobium diboride by fluorine bomb calorimetry

Johnson, Gerald Kenneth. January 1964 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 42-46.
5

Calibrating the electromagnetic calorimeter of T2K

George, Melissa January 2010 (has links)
In this thesis, I describe the first calibration of the T2K ND280 electromagnetic calorimeter using cosmic muons. T2K is a long baseline neutrino oscillation experiment whose main aim is to observe for the first time the νμ→νe oscillations. A complete understanding of the νμ disappearance or νμ→νx oscillations, x = μ or τ , and neutrino-nucleon interactions will complete the T2K physics programme. T2K produces an intense muon neutrino beam at the J-PARC facility on Japan's East coast. This neutrino beam is then detected twice: once 280 m from its start by ND280 - whose purpose is to characterise the beam - and then again 295 km away at the far detector SuperKamiokande on the West coast of Japan. One of the components of the ND280 detector is the electromagnetic calorimeter. A thorough understanding of the electromagnetic calorimeter is crucial. In this thesis I first describe the quality assurance of the photosensors used in the calorimeter. Then I describe the cosmic muon flux simulation, that I adapted from CORSIKA for the electromagnetic calorimeter studies, and now adopted by the whole T2K collaboration. This is followed by a description of calibration of the calorimeter using the cosmic muon flux, in particular the light yield attenuation, and finally the comparison of the results obtained with cosmic muons taken at two different locations, CERN and Tokai. Moreover, I describe the ND280 Workbook, an online guide to the ND280 software, including tutorials and information for all the ND280 collaborators, that I developed in its entirety.
6

Estudo da produção de J/ com o experimento ALICE utilizando o calorímetro eletromagnético / The study of J?Y production with the ALICE experimente using the electromagnetic calorimeter

Figueredo, Marcel Araujo Silva 08 May 2013 (has links)
Neste trabalho, obteve-se a medida da seção de choque de produção de J/ com pT > 5 GeV/c em rapidez central (|y| < 0, 7), valendo-se de eventos selecionados pelo trigger do calorímetro eletromagnético (EMCal) do experimento ALICE-LHC, em colisões prótonpróton com s = 7 TeV. Essa medida é importante pela possibilidade de se estudar modelos de produção de estados de heavy-quarkonium, além de servir como referência para o estudo da produção de J/ em colisões Pb-Pb, nas quais forma-se o Plasma de Quarks e Glúons (QGP Quark Gluon Plasma). Essa medida foi separada em 4 intervalos de pT , obtendo-se assim um espectro de pT do J/ para pT > 5 GeV/c. Os valores obtidos da seção de choque diferencial (d2/dpT dy) foram: 0.42 ± 0,11(est.) ± 0,13(sis.) b GeV/c para pT entre 5 e 7 GeV/c, 0,18 ± 0,03(est.) ± 0,04(sis.) b GeV/c para pT entre 7 e 9 GeV/c, 0,041 ± 0,008(est.) ± 0,008(sis.) b GeV/c para pT entre 9 e 11 GeV/c e 0,014 ± 0,003(est.) ± 0,005(sis.) b GeV/c para pT entre 11 e 14 GeV/c. Esses valores são compatíveis com cálculos da QCD não relativística (NRQCD) e com o modelo de evaporação de cor (CEM). Além disso, na região de intersecção de pT , os resultados são compatíveis com aqueles obtidos pelo experimento ALICE (para baixo momento) e com as medidas obtidas pelo experimento ATLAS (para pT > 6 GeV/c). Além disso, por intermédio da reconstrução do vértice de decaimento do J/, foi possível estimar a fração de J/s que vieram de decaimentos de mésons B (fB). Os valores obtidos foram: fB = 0,267 ± 0,114 (hpT i = 7,15 GeV/c), fB = 0,338 ± 0,116 (hpT i = 10,7 GeV/c), fB = 0,271 ± 0,087 (hpT i = 8,5 GeV/c), que são compatíveis, dentro das incertezas experimentais, com valores obtidos no experimento ATLAS. Um último estudo realizado foi a viabilidade de medida de J/ com valor de pT > 6 GeV/c em colisões Pb-Pb. Para isso, valendo-se do sistema de trigger de L1 do EMCal, foram obtidos 93 ± 16 J/ reconstruídos em uma região de centralidade de 20-60%. / This work presents the measurement of the J/ production with pT > 5 GeV/c at midrapidity (|y| < 0.7) with the ALICE experiment in 7 TeV proton-proton collisions, using the electromagnetic calorimeter (EMCal) triggered events. This measurement is very important due to the possibility of studying models that predict the heavy quarkonium production, and it also provides baseline results to be compared with the J/ production in PbPb, where the Quark Gluon Plasma (QGP) is formed. This measurement was separated into 4 pT bins in order to reproduce a J/ pT spectrum. The differential cross section (d2/dpT dy) results achieved were: 0.42 ± 0.11(est.) ± 0.13(sys.) b GeV/c for pT between 5 and 7 GeV/c, 0.18 ± 0.03(est.) ± 0.04(sys.) b GeV/c for pT between 7 and 9 GeV/c, 0.041 ± 0.008(est.) ± 0.008(sys.) b GeV/c for pT 9 and 11 GeV/c and 0,014 ± 0,003(est.) ± 0,005(sis.) b GeV/c for pT between 11 and 14 GeV/c. These values are compatible with Non-Relativistic (NRQCD) and Color Evaporation model (CEM) predictions. Besides, they are also compatible with results from ALICE (low pT ) and with ATLAS results (for pT > 6 GeV/c). This work also shows the measurement of the fraction of non-prompt J/ (fB). The results were: fB = 0,267 ± 0,114 (hpT i = 7,15 GeV/c), fB = 0,338 ± 0,116 (hpT i = 10,7 GeV/c), fB = 0,271 ± 0,087 (hpT i = 8,5 GeV/c), which are compatible with ATLAS results. The last study made in this work was the feasility of the measurement of J/ in Pb-Pb collisions for pT > 6 GeV/c, using the EMCal L1 Gamma trigger. Considering events from the centrality region 20-60%, 93 ± 16 J/s were reconstructed.
7

The use of small scale fire test data for the hazard assessment of bulk materials

Foley, Marianne January 1995 (has links)
An experimental study of fire testing of solid materials has been carried out to investigate whether or not these tests yield useful data for the burning of materials stored in bulk, for example in warehouses. Tests were performed using the Cone Calorimeter, the HSE third scale room/corridor rig, BS 5852 part 2, and some nonstandard tests. The results have been compared and the problems with fire testing have been discussed with reference to the current literature and trends in fire testing. The additional complications of unusual material behaviour under exposure to heating have also been investigated. In the third scale room/corridor test, where vertical, parallel samples are used, the separation distance between the samples was found to play a significant part in whether ignition of fire retarded samples could be achieved or not. A literature survey revealed a dearth of information on this subject. As this type of parallel configuration is found in warehouse storage as well as vertical ducts and cavities, an investigation was conducted into flames between vertical parallel walls. Measurements were made of total and radiative heat fluxes at the walls, flame and gas temperatures, and flame heights under a variety of conditions. It was found that the configuration of the system was very important, with the separation distance and fluid dynamics both having a major influence. Burner position, geometry and heat release rate were also varied and their influence assessed. Statistical methods were employed to correlate the heat flux data and temperatures with the other variables, with excellent correlation coefficients for the equations developed. These have been compared with previous expressions developed for flames against vertical walls. Results from CFD work on two of the parallel wall cases of special interest were analysed and discussed with reference to the . experimental results. The findings have implications for the fire testing of materials, and for the hazard assessment of materials stored in high rack storage. An understanding of potential exposure conditions in a real fire scenario are essential for the appropriate use of fire tests.
8

Thermal runaway reaction hazard and decomposition mechanism of the hydroxylamine system

Wei, Chunyang 30 October 2006 (has links)
Chemical reactivity hazards have posed a significant challenge for industries that manufacture, store, and handle reactive chemicals. Without proper management and control of reactivity, numerous incidents have caused tremendous loss of property and human lives. The U.S. Chemical Safety and Hazard Investigation Board (CSB) reported 167 incidents involving reactive chemicals that occurred in the U.S. from 1980 to 2001. According to the report, 35 percent of the incidents were caused by thermal runaway reactions, such as incidents that involved hydroxylamine and hydroxylamine nitrate. The thermal stability of hydroxylamine system under various industrial conditions was studied thoroughly to develop an understanding necessary to prevent recurrence of incidents. The macroscopic runaway reaction behavior of hydroxylamine system was analyzed using a RSST (Reactive System Screening Tool) and an APTAC (Automatic Pressure Tracking Calorimeter). Also, computational chemistry was employed as a powerful tool to evaluate and predict the measured reactivity. A method was proposed to develop a runaway reaction mechanism that provides atomic level ofinformation on elementary reaction steps, in terms of reaction thermochemistry, activation barriers, and reaction rates. This work aims to bridge molecular and macroscopic scales for process safety regarding reactive chemicals and to understand macroscopic runaway reaction behaviors from a molecular point of view.
9

Estudo da produção de J/ com o experimento ALICE utilizando o calorímetro eletromagnético / The study of J?Y production with the ALICE experimente using the electromagnetic calorimeter

Marcel Araujo Silva Figueredo 08 May 2013 (has links)
Neste trabalho, obteve-se a medida da seção de choque de produção de J/ com pT > 5 GeV/c em rapidez central (|y| < 0, 7), valendo-se de eventos selecionados pelo trigger do calorímetro eletromagnético (EMCal) do experimento ALICE-LHC, em colisões prótonpróton com s = 7 TeV. Essa medida é importante pela possibilidade de se estudar modelos de produção de estados de heavy-quarkonium, além de servir como referência para o estudo da produção de J/ em colisões Pb-Pb, nas quais forma-se o Plasma de Quarks e Glúons (QGP Quark Gluon Plasma). Essa medida foi separada em 4 intervalos de pT , obtendo-se assim um espectro de pT do J/ para pT > 5 GeV/c. Os valores obtidos da seção de choque diferencial (d2/dpT dy) foram: 0.42 ± 0,11(est.) ± 0,13(sis.) b GeV/c para pT entre 5 e 7 GeV/c, 0,18 ± 0,03(est.) ± 0,04(sis.) b GeV/c para pT entre 7 e 9 GeV/c, 0,041 ± 0,008(est.) ± 0,008(sis.) b GeV/c para pT entre 9 e 11 GeV/c e 0,014 ± 0,003(est.) ± 0,005(sis.) b GeV/c para pT entre 11 e 14 GeV/c. Esses valores são compatíveis com cálculos da QCD não relativística (NRQCD) e com o modelo de evaporação de cor (CEM). Além disso, na região de intersecção de pT , os resultados são compatíveis com aqueles obtidos pelo experimento ALICE (para baixo momento) e com as medidas obtidas pelo experimento ATLAS (para pT > 6 GeV/c). Além disso, por intermédio da reconstrução do vértice de decaimento do J/, foi possível estimar a fração de J/s que vieram de decaimentos de mésons B (fB). Os valores obtidos foram: fB = 0,267 ± 0,114 (hpT i = 7,15 GeV/c), fB = 0,338 ± 0,116 (hpT i = 10,7 GeV/c), fB = 0,271 ± 0,087 (hpT i = 8,5 GeV/c), que são compatíveis, dentro das incertezas experimentais, com valores obtidos no experimento ATLAS. Um último estudo realizado foi a viabilidade de medida de J/ com valor de pT > 6 GeV/c em colisões Pb-Pb. Para isso, valendo-se do sistema de trigger de L1 do EMCal, foram obtidos 93 ± 16 J/ reconstruídos em uma região de centralidade de 20-60%. / This work presents the measurement of the J/ production with pT > 5 GeV/c at midrapidity (|y| < 0.7) with the ALICE experiment in 7 TeV proton-proton collisions, using the electromagnetic calorimeter (EMCal) triggered events. This measurement is very important due to the possibility of studying models that predict the heavy quarkonium production, and it also provides baseline results to be compared with the J/ production in PbPb, where the Quark Gluon Plasma (QGP) is formed. This measurement was separated into 4 pT bins in order to reproduce a J/ pT spectrum. The differential cross section (d2/dpT dy) results achieved were: 0.42 ± 0.11(est.) ± 0.13(sys.) b GeV/c for pT between 5 and 7 GeV/c, 0.18 ± 0.03(est.) ± 0.04(sys.) b GeV/c for pT between 7 and 9 GeV/c, 0.041 ± 0.008(est.) ± 0.008(sys.) b GeV/c for pT 9 and 11 GeV/c and 0,014 ± 0,003(est.) ± 0,005(sis.) b GeV/c for pT between 11 and 14 GeV/c. These values are compatible with Non-Relativistic (NRQCD) and Color Evaporation model (CEM) predictions. Besides, they are also compatible with results from ALICE (low pT ) and with ATLAS results (for pT > 6 GeV/c). This work also shows the measurement of the fraction of non-prompt J/ (fB). The results were: fB = 0,267 ± 0,114 (hpT i = 7,15 GeV/c), fB = 0,338 ± 0,116 (hpT i = 10,7 GeV/c), fB = 0,271 ± 0,087 (hpT i = 8,5 GeV/c), which are compatible with ATLAS results. The last study made in this work was the feasility of the measurement of J/ in Pb-Pb collisions for pT > 6 GeV/c, using the EMCal L1 Gamma trigger. Considering events from the centrality region 20-60%, 93 ± 16 J/s were reconstructed.
10

Measurement of Thermal Properties of Seafood

Radhakrishnan, Sudhaharini 14 July 1997 (has links)
Thermal properties of ten different seafood were measured in this research. They included bluefish (<i>Pomatomus saltatrix</i>), croaker (<i>Micropogonias undulatus</i>), spanish mackerel (<i>Scomberomorus maculatus</i>), pink salmon (<i>Oncorhynhus gorbuscha</i>), black seabass (<i>Atractoscion nobilis</i>), spot (<i>Leiostomus xanthurus</i>), shrimp(<i>Pandalus borealis</i>), tilapia (<i>Tilapia aurea</i>), grey sea trout(</i>Cynoscion regalis</i>), and yellow fin tuna (<i>Thunnus albacares</i>) (Wheaton, et al. 1985). Thermal properties measured were thermal conductivity, thermal diffusivity, and specific heat from 5 to 30<sup>o</sup>C. Enthalpy was measured from -40 to 30<sup>o</sup>C. Moisture and fat content were measured. Thermal conductivity and thermal diffusivity were measured by a rapid transient technique using a bead thermistor probe. Specific heat and enthalpy were measured using a differential scanning calorimeter. Moisture content and fat content were measured by the AOAC specified oven dry method and ether extraction method, respectively. The measured thermal properties agreed well with the scarcely available literature values. They were then statistically correlated with moisture and fat content. Based on statistical analysis, mathematical models relating thermal properties and composition were proposed and compared with the models available in the literature. Models for thermal conductivity and specific heat were recommended to predict these properties of meats and fish with similar composition. / Master of Science

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