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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

Estudo do comportamento de extracao de varios elementos por aminas de cadeias longas na presenca de tioureia como complexante

ABRAO, ALCIDIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:34Z (GMT). No. of bitstreams: 1 00487.pdf: 3661136 bytes, checksum: c0260dd586757d95cff8f019550e024b (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Quimica, Universidade de Sao Paulo, Sao Paulo
2

Estudo do comportamento de extracao de varios elementos por aminas de cadeias longas na presenca de tioureia como complexante

ABRAO, ALCIDIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:34Z (GMT). No. of bitstreams: 1 00487.pdf: 3661136 bytes, checksum: c0260dd586757d95cff8f019550e024b (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Quimica, Universidade de Sao Paulo, Sao Paulo
3

Analyse dynamique des structures multicouches soumise à une force d'impact : application aux chaussées / Dynamic analysis of multilayered structures under impact load : application to pavement structures

Asli, Cherif 10 January 2013 (has links)
Actuellement, l’identification des modules d’élasticité des différentes couches des chaussées est basée sur des modèles statiques. Ce travail de thèse consiste à développer une approche dynamique qui permet de représenter plus fidèlement la nature dynamique des essais FWD. L’étude semi-analytique à l’aide de la méthode des éléments spectraux est développée pour identifier les paramètres inconnus du système. L’analyse par la méthode des éléments finis permet de cerner au mieux le phénomène d’impact FWD et de mieux comprendre le comportement dynamique des chaussées sous forces d’impact. Le code FER/Impact développé au laboratoire LMEE est utilisé pour la simulation des essais au FWD. Le modèle numérique de la chaussée est un modèle multicouche axisymétrique dont les matériaux des différentes couches est supposés homogène, isotropes et élastiques. Pour prendre en compte l’atténuation des phénomènes dynamiques générés dans le milieu multicouche, l’amortissement de type Rayleigh est considéré. Un appareil innovant est développé pour caractériser les matériaux des plateformes. La méthode des moindres carrés est utilisée pour l’évaluation des modules d’élasticité. La confrontation des résultats expérimentaux et numériques permet de valider l’approche dynamique. / Up to now, the identification of the modulus of elasticity of various layers of pavement is based on static models. The present work consists in developing a dynamic approach which allows representing better the dynamic nature of the FWD test. The semi-analytical study by means of the spectral method is developed to identify unknown parameters of the system. Finite element analysis of the FWD test allows understanding better the dynamic behavior of pavement under impact loadings. The FER/Impact code developed in the LMEE laboratory is applied to simulate a multi-layers pavement model under axisymmetric conditions. The materials of the various layers are supposed homogeneous, isotropic and elastic. To take into account the attenuation of the dynamic phenomena generated in the multilayers media, Rayleigh damping is considered. An innovative device is developed to characterize the material properties of subgrade and foundation. The method of least squares is used for the back-calculation of the modulus of elasticity.. The confrontation of the experimental and numerical results validates the dynamic approach.
4

Trace elements (MN, B, Zn, Cu and Mo) their effect on the growth of trees, particularly Pinus resinosa, Robinia pseudoacacia and Alnus glutinosa /

Iyer, Jaya Ganpathi, January 1962 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 43-51).
5

Ordered Triples

Monozingo, Montie Gene 08 1900 (has links)
The purpose of this paper is the investigation of various properties of ordered triples whose components are elements of certain sets.
6

Finite Element Approximations of Burgers' Equation with Robin's Boundary Conditions

Smith, Lyle C. III 14 August 1997 (has links)
This work is a numerical study of Burgers' equation with Robin's boundary conditions. The goal is to determine the behavior of the solutions in the limiting cases of Dirichlet and Neumann boundary conditions. We develop and test two separate finite element and Galerkin schemes. The Galerkin/Conservation method is shown to give better results and is then used to compute the response as the Robin's Boundary conditions approach both the Dirichlet and Neumann boundary conditions. Burgers' equation is treated as a perturbation of the linear heat equation with the appropriate realistic constants. The goal is to determine if the use of the Robin's boundary conditions to approximate Dirichlet and Neumann boundary conditions affords any advantage over schemes that employ only "exact" Dirichlet or Neumann boundary conditions. Our finite element results indicate that solutions using appropriate Robin's boundary conditions approach the same solutions obtained by "exact" Dirichlet or Neumann boundary conditions. This allows us to obtain realistic solutions in some cases where the other schemes had previously failed. / Master of Science
7

STORY ELEMENTS: WHICH IMPACT CHILDREN'S READING INTERESTS?

Kauffman, Syndi 05 July 2005 (has links)
No description available.
8

ANALYTICAL STRESS ANALYSIS SOLUTION FOR A SIMPLIFIED MODEL OF A REACTOR FUEL ELEMENT

Lamkin, David Ernest, 1940- January 1974 (has links)
No description available.
9

Bioavailability of cadmium, copper, nickel and zinc in soils treated with biosolids and metal salts : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University /

Black, Amanda. January 2010 (has links)
Thesis (Ph. D.) -- Lincoln University, 2010. / Main page numbering ends at 206 followed by single page numbered 224. Also available via the World Wide Web.
10

Chromium in San Francisco Bay inorganic speciation, distribution, and geochemical processes /

Abu-Saba, Khalil Elias. January 1994 (has links)
Thesis (M.S.)--University of California, Santa Cruz, 1994. / Typescript. Includes bibliographical references (leaves 159-166).

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