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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.
11

Clay modification for the production of polystyrene nanocomposites by melt processing

Uribe Calderón, Jorge Alonso. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Chemical Engineering. Title from title page of PDF (viewed ). Includes bibliographical references.
12

Rock phosphate availability as influenced by soil pH [I.] II. Phosphate fixation by montmorillonite /

Ellis, Roscoe. January 1954 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1954. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies: leaves 44, 73-74.
13

Montmorillonites and vermiculites of soils chemical composition and cation exchange behavior.

Sawhney, B. L. January 1957 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Abstracted in Dissertation abstracts, v. 18 (1958) no. 6, p. 1922-1923. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 99-108).
14

Montmorillonite genesis in soils as influenced by the activities of monosilicic acid and various cations in the matrix solution

Weaver, Robert Michael, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
15

Thermal and structural properties of polyamide/montmorillonite nanocomposites toughened with SEBS

Kwong, Chin Fai. January 2004 (has links) (PDF)
Thesis (M.Sc.)--City University of Hong Kong, 2004. / At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 1, 2006) Includes bibliographical references.
16

Mechanical characteristics of PA6-monmorillonite [i.e. montmorillonite] nanocomposites

Yau, Alvin. January 2004 (has links) (PDF)
Thesis (M.Sc.)--City University of Hong Kong, 2004. / At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
17

Creation of clay flameless burner for vaporizing an insect repellent containing pmd as an active ingredient

Akwi, Faith Mary January 2012 (has links)
Insecticide treated mosquito bed nets, insecticide aerosol sprays, repellent lotions and creams, repellent candles, vaporizable repellent essential oils, mosquito mats and coils are some of the many malaria personal protection tools that are in use. The latter of these measures are the most accessible and affordable options for the rural population in sub-Saharan Africa. It is therefore important to determine how effective these personal protection measures are by determining their ability to efficiently disperse an active ingredient when the protection measure is in use. In this study, a copper II oxide montmorillonite clay burner (CuOMontmorillonite clay burner) was created to vaporize repellent formulations containing various concentrations of p-menthane-3,8-diol (PMD) as the active ingredient with the aim of determining the percentage of the active ingredient that is released into the air and the rate of release. The performance of the CuO-Montmorillonite clay burner was also compared to that of the Lampe Berger fragrance burner (LBFB). In addition to this, the percentage of PMD released from 6 percentage wt PMD candles of diameters 40mm, 69mm and 83mm was determined and compared to that released when the CuO-Montmorillonite clay burner and Lampe Berger Fragrance burner where used to vaporize PMD repellent formulations. It was found that the rate of vaporization of the various PMD repellent formulations vaporized using the Lampe Berger fragrance burner is affected by the mass of PMD present in the repellent formulations. The 6 percentage wt PMD repellent candles released the least percentage of PMD as compared to that released when the CuO-Montmorillonite clay burner and the Lampe Berger fragrance burner were used to vaporize the PMD repellent formulations.
18

Copper, lead and zinc sorption on Wyoming montmorillonite

Cooper, Roger Brian January 1976 (has links)
Exchange adsorption of Cu²⁺ , Pb²⁺ and Zn²⁺ for Na on Wyoming mont-morillonite, in chloride and nitrate electrolyte solutions less than 10⁻³ M total heavy metal concentration, can be modelled with a simple equilibrium ion-exchange reaction: Me²⁺ + 2 Na{Mont} = Me{Mont}₂ + 2 Na⁺ where Me. and Mont represent a given heavy metal and montmorillonite. Equilibrium constants for this reaction are equal for Cu²⁺ and Zn²⁺ at 3.0 ± 1, slightly less than that for Pb²⁺ at 5.0 ± 1, and comparable to constants calculated for monopositive exchange of K⁺ for Na⁺ (3.0 ± 1) and H⁺ for Na⁺ (2.5 ± .5). Above 10⁻³ M total metal concentration, heavy metal exchange for Na is complicated by variable total Na exchange capacity and by apparent anionic interferences. CuCl₂ and ZnCl₂ electrolyte solutions are more effective Na exchangers at 0.1 M than Cu(NO₃)₂, Pb(NO₃)₂, KC1 or HC1 solutions at the same concentration. Retardation factors of Cu, Pb and Zn spots eluted across thin layers of Na-montmorillonite (supported by silica gel) by aqueous NaCl and NaNO₃ solutions of 0.05 to 3.0 M concentration suggest, when interpreted with a rudimentary ion-exchange mass transfer model, that metals migrate mainly as monopositive species—perhaps as monohydroxo-complexes within the clay micelle. Precipitation of Pb chloride or hydroxy-chloride is indicated by multiple Pb spots on NaCl-eluted chromatograms. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
19

Desorption isotherms of montmorillonite-organic complexes /

Kalb, George William January 1969 (has links)
No description available.
20

Polyamide-imide and Montmorillonite Nanocomposites

Ranade, Ajit 08 1900 (has links)
Solvent suspensions of a high performance polymer, Polyamide-imide (PAI) are widely used in magnetic wire coatings. Here we investigate the effect that the introduction of montmorillonite (MMT) has on PAI. MMT was introduced into an uncured PAI suspension; the sample was then cured by step-wise heat treatment. Polarized optical microscopy was used to choose the best suitable MMT for PAI matrix and to study the distribution of MMT in PAI matrix. Concentration dependent dispersion effect was studied by x-ray diffraction (XRD) and was confirmed by Transmission electron microscopy (TEM). Differential scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA) was used to study impact of MMT on glass transition temperature (Tg) and degradation properties of PAI respectively. Micro-hardness testing of PAI nanocomposites was also performed. A concentration dependent state of dispersion was obtained. The glass transition (Tg), degradation and mechanical properties were found to correlate to the state of dispersion.

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