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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.
101

Removal of Nitrate, Arsenic and Vanadium in Bench-scale Biological Filters

Schmidt, Jordan Jeremy 24 April 2012 (has links)
Nitrate, arsenic and vanadium are all potential groundwater contaminants. Traditional physical/chemical methodologies are often too technical or expensive for rural environments. Biofiltration has been shown to remove a wide range of contaminants depending on the operating parameters. This research examined the possibility of using the denitrifying bacteria, Paracoccus denitrificans, to remove nitrate, arsenic and vanadium simultaneously from groundwater with varying iron concentrations. During bench-scale testing nitrate concentrations were reduced by up to 73%, even with the metals present. Without iron, arsenic and vanadium removal was insignificant. Removal increased when iron was added as it was found that arsenic and vanadium could be removed adsorptively by iron hydroxides. With 1 mg/L of iron present, removal rates of 67% and 91% were achieved for arsenic and vanadium, respectively. When the iron was increased to 2 mg/L, the removal rates increased to 85% and 96%, respectively.
102

VOx /TiO2 anode catalyst for oxidation of CH4 containing 5000 ppm H2S in SOFC

Garcia Rojas, Alfonso Andres Unknown Date
No description available.
103

Dissolution of high melting point additions in liquid steel

Argyropoulos, Stavros A. January 1981 (has links)
The kinetics of dissolution of titanium and vanadium in liquid steel has been studied. Two periods were distinguished: the steel shell period and the free dissolution period. / In the case of titanium, it is shown that the customary frozen shell of steel encases the cylinder following its initial immersion. Premature internal dissolution then begins as a result of liquid eutectic of Fe(,0.3) Ti(,0.7) composition forming at the inner steel shell boundary. This phenomenon triggers an exothermic dissolution and erosion of the inner steel shell. The net result is considerable shortened shell melting times. During the free dissolution period, the temperature of the titanium dissolving at the interface increases and the dissolution process becomes self-accelerating. / During the steel shell period with pure vanadium and ferrovanadium alloys, no reaction was observed between the steel shell and vanadium. For low grade ferrovanadium alloys, the dissolution proceeds via a heat transfer mechanism. On the other hand, for high grades, ferrovanadium mass transfer mechanisms dominate. / A simplified mathematical model of the process has been developed to describe the coupled heat and mass transfer phenomena involved in the various systems studied.
104

Surface structure and related properties of the (100) surfaces of vanadium and niobium

Lacina, David Glenn. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
105

Ligand controlled metal-metal bond formation in the chemistry of low-valent vanadium and chromium fact or fiction? /

Edema, Jilles Joseph Heinrich, January 1991 (has links)
Proefschrift Rijksuniversiteit Groningen. / Met lit. opg. - Met een samenvatting in het Nederlands.
106

Spectroscopic studies of vanadium and chromium in crystalline and amorphous silica matrices

Carter, Donald F. Stiegman, Albert E. January 2004 (has links)
Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Albert E. Stiegman, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Sept. 27, 2004). Includes bibliographical references.
107

The replacement of molybdenum by vanadium in ammonium phosphomolybate II. A new method for the determination of phosphorus in the prescence of vanadium ...

Scoles, Dwight L., January 1926 (has links)
Thesis (Ph. D.)--Columbia University, 1926. / Vita. Bibliography: p. [32].
108

Structural and bonding studies of M(h⁵-C₅H₅)₂L₂ complexes by x-ray diffraction, electron paramagnetic resonance, approximate molecular orbital calculations, and photoelectron spectroscopy

Petersen, Jeffrey Lee, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1974. / Transcript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
109

The behavior of iron and manganese sulfides during the solidification and processing of steels containing vanadium, titanium, and zirconium

Harris, Kenneth Wesley, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
110

Structural studies of polyoxoanionic solids by vanadium-51 and phosphorus-31 solid state magic angle spinning NMR spectroscopy

Huang, Wenlin. January 2007 (has links)
Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: Tatyana Polenova, Dept. of Chemistry & Biochemistry. Includes bibliographical references.

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