• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 936
  • 776
  • 229
  • 153
  • 50
  • 26
  • 22
  • 20
  • 20
  • 20
  • 20
  • 20
  • 20
  • 14
  • 13
  • Tagged with
  • 2656
  • 566
  • 203
  • 198
  • 190
  • 150
  • 144
  • 137
  • 128
  • 124
  • 120
  • 118
  • 115
  • 108
  • 103
  • 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

An apparatus to study the pool boiling of sodium

Wendte, James Conway. January 1961 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1961. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-130).
2

Studies in the optical spectrum of singly ionized sodium, Na II

Wu, Chien-Ming January 1971 (has links)
The spectrum of the singly ionized sodium ion, Na II, has been photographed in the region between 350 Ɣ and 9000 Ɣ using as sources a condensed electrodeless discharge and a condensed spark in helium. Exposures were taken on a 3-meter normal-incidence vacuum grating spectrograph, on a 21-foot concave grating spectrograph, on a Hilger E-478 large interchangeable quartz and glass prism spectrograph, and Fabry-Perot interferometer. The term system has been revised and much extended. Five hundred and twenty-seven lines (with twenty doubly identified) are classified as combinations between sixty-two odd levels and seventy-one even levels. The ionization limits, 2s² 2p⁵(²P₃⁄₂) and 2s² 2p⁵ (²P₁⁄₂), have been redetermined as 381390.2 cm⁻¹ and 382756.6 cm⁻¹ (±2.0 cm⁻¹). / Science, Faculty of / Physics and Astronomy, Department of / Graduate
3

Conception de bio-indicateurs de polluant organique et de métaux lourds par encapsulation de micro-algues dans une matrice de silice synthétisée par le procédé sol-gel / Design of bioindicators of organic pollutant and heavy metals by encapsulation of microalgae in silica matrix synthesized by the sol-gel process

Ben Ahmed, Nada 25 October 2016 (has links)
Le travail s’inscrit dans un cadre interdisciplinaire, à l’interface de la chimie sol-gel, la biologie et la physique des matériaux. Nous nous sommes intéressés en premier lieu à l’étude d’une matrice de silice obtenue par le procédé sol-gel à partir d’un mélange de silice colloïdale et de silicates de sodium. Le but était de comprendre les interactions entre les précurseurs et d’étudier l'effet des différents paramètres de synthèse sur la structure de la matrice afin de trouver les meilleures propriétés optiques et mécaniques. Ces matrices ont été largement caractérisées au moyen de différentes techniques (absorption UV-Visible, infrarouge, ATG, BET, RMN, MET et MEB). Cette étude nous permet pour la première fois de partir des propriétés finales désirées et de préciser la combinaison nécessaire pour les obtenir en termes de concentrations des précurseurs et de pH. Ensuite, nous avons pu étudier l’effet des propriétés de la matrice sur la survie des cellules photosynthétiques encapsulées et on a pu obtenir des matériaux phyco-compatibles avec une large gamme de propriétés optiques et mécaniques. Après avoir fixé les conditions de synthèse convenables pour la survie des micro-organismes, on a pu passer à l’étude de la fonctionnalité des matériaux en présence des contaminants toxiques (qui sont les métaux lourds Cd (II) et Pb (II) et un hydrocarbure aromatique polycyclique l’anthracène) et on a réussi à obtenir un biocapteur fonctionnel. De façon intéressante, une certaine spécificité de la détection a pu être obtenue en fonction du couple microalgue/matrice choisi / The work is an interdisciplinary framework, at the interface of the sol-gel chemistry, biology and physics of materials. First, we are interested to the study of a silica matrix obtained by sol-gel process from a mixture of colloidal silica and sodium silicate. The goal was to understand the interactions between the precursors and to study the effect of different synthesis parameters on the structure of the matrix in order to find the best optical and mechanical properties. These matrices have been extensively characterized using various techniques (UV-Visible absorption, IR, TGA, BET, NMR, TEM and SEM). This study allows us for the first time to choose final properties and to specify the initial combination to get them in terms of concentrations of precursors and pH. Next, we studied the effect of the matrix properties on the survival of photosynthetic encapsulated cells and we got phyco-compatible materials with a wide range of optical and mechanical properties. After precising the best synthesis conditions for the survival of microorganisms, one could proceed to study the functionality in the presence of toxic contaminants (heavy metals Cd (II) and Pb (II) and a polycyclic aromatic hydrocarbon: anthracene) and we managed to get a functional biosensor. Interestingly, some specificity of detection could be obtained according to the combination of microalga / selected matrix
4

Self-Diffusion of Na-²² in Molten PbCl₂-NaCl Mixtures

Hsu, Yuan Tsun 01 1900 (has links)
This thesis contains the exploration and investigation of self-diffusion of Na-22 in Molten PbCl2-NaCl mixtures.
5

The reaction of quaternary ammonium halides with sodium

Blanchard, Elwood Parry 08 1900 (has links)
No description available.
6

The behavior of sodium silicofluoride in ceramic bodies

Palmour, Hayne 05 1900 (has links)
No description available.
7

On the reactions of sodium benzhydrol ... /

Bacon, Raymond Foss, January 1905 (has links)
Thesis (PH. D.)--University of Chicago. / Includes bibliographical references. Also available on the Internet.
8

On the reactions of sodium benzhydrol ...

Bacon, Raymond Foss, January 1905 (has links)
Thesis (Ph. D.)--University of Chicago. / Includes bibliographical references.
9

On sodium phenyl and the action of sodium on ketones ...

Acree, Solomon Farley. January 1903 (has links)
Thesis (Ph. D.)--University of Chicago.
10

On the reactions of sodium benzhydrol ...

Bacon, Raymond Foss, January 1905 (has links)
Thesis (Ph. D.)--University of Chicago. / Includes bibliographical references.

Page generated in 0.0658 seconds