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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

Sulfur chemistry st[r]ucture and reactivity of substituted thioreas and aminothiols of physiological importance /

Mundoma, Claudius. January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xvii, 217 p. : ill. Includes abstract. Includes bibliographical references.
2

X-koolstofreaktiwiteit van enkele gekoordineerde swaelligande in chroom(0)- en mangaan(1) komplekse

01 September 2015 (has links)
M.Sc. / Since the discovery of Ni(CO)4 by Mond in 1890, many chemists became interested in organometallic chemistry. This field of research expanded after the synthesis of ferrocene in 1951. organometallic complexes are widely used in organic synthesis, especially as catalysts ...
3

Reductive cleavage of the carbon-sulfur bond in bridged thiolato complexes.

January 1987 (has links)
Ngan-fong Ho. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1987. / Bibliography: leaves 57-64.
4

SYNTHESES AND CHEMICAL INVESTIGATIONS OF POSSIBLE SINGLET DIATOMIC SULFUR PRECURSORS

Smith, Douglas Lee, 1947- January 1976 (has links)
No description available.
5

Synthesis of indolocarbazoles, bisindoles and related sulfur containing systems /

Janosik,Tomasz, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 7 uppsatser.
6

Organic sulfur compounds and the microbial sulfur cycle

Zinder, Stephen Henry. January 1977 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references.
7

Metodologie vir die sintese van chirale tiofeenderivate

Van Zyl, Wynand Jacobus 22 October 2015 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract
8

Equilibrium studies of complex compounds of sulphur

Gidden, R. D. January 1965 (has links)
No description available.
9

Volatile sulfur compounds from high heat treatment of milk /

Pereira, Ronald Roy January 1965 (has links)
No description available.
10

DETERMINATION OF SULFUR SPECIES IN SOLIDS BY TIME RESOLVED MOLECULAR EMISSION SPECTROMETRY

Schubert, Steven Ashley January 1980 (has links)
Excessive levels of sulfur in the ecosphere are generally found to be detrimental to man and his environment. Four inorganic forms of sulfur are singled out as common constituents of natural and pollutant systems: sulfide (S²⁻), elemental sulfur (S⁰), sulfite (SO₃²⁻), and sulfate (SO₄²⁻). Progress toward characterizing the chemical interactions and toxicity of these species is retarded by the lack of suitable analytical procedures for determining the forms of sulfur in complex solid matrices. An extensive survey of the literature reveals that conventional analyses for sulfur are numerous, but that most techniques are restricted to solutions containing only one type of sulfur. A few complex and cumbersome analytical schemes have been devised, however, for the determination of mixtures of sulfur species in solution. Solubilization of the sample prior to analysis not only adds a step to the procedure, but it also increases the number of variables and the uncertainty associated with the results. The direct determination of sulfur in solids is an alternative to extraction which avoids many of its pitfalls. A critical review of the methods available discloses a paucity of analytical techniques capable of determining individual sulfur species in solid mixtures. X-Ray methods such as X-ray fluorescence and X-ray photoelectron spectroscopy rank the highest as potentially useful probes for eliciting information concerning the oxidation state of sulfur in solids. Routine quantitative work is impeded by the inability to examine bulk properties and the relative lack of sensitivity inherent in X-ray techniques. This apparent analytical void has led to the development of a new technique which can be applied to the determination of inorganic sulfur in solids: time resolved molecular emission spectrometry (TRMES). Solid samples are placed in a small, quartz-lined cavity at the end of a stainless steel rod and the rod is positioned in a low temperature flame, in line with the entrance slit of monochromator. The resulting molecular sulfur emission is monitored at 383.6 nm and is linearly related to sulfur content between at least 10⁻⁵ to 10⁻⁷ g. Qualitative identification of sulfide, elemental sulfur, sulfite, and sulfate is afforded by the separate, time dependent emission responses which are observed. Detection limits are species dependent and theoretically, in a 1.5-mg sample, range from 0.2 pg for sulfite to 8ng for sulfate. In practice, quantitation at these low levels is hindered by inhomogeneous standards. Effects due to different bulk matrices, the presence of two or more sulfur species in a sample, or interferences from counterions are minimal or have not been detected. TRMES provides an alternative to aspirating the sample into the flame and greatly reduces the amount of sample that is required. In addition, the cavity serves to confine the sample and the resultant emission to a small, predetermined region of the flame. This enhances sensitivity and allows one to choose the optimum sample position in the flame. Standard flame emission instruments may be readily adapted to this technique by the addition of a simple, easily fabricated sample introduction device. The utility of TRMES is demonstrated by the determination of sulfur species in several complex matrices, including: coal (S₂²⁻); copper and lead smelter particulates (S²⁻, SO₃²⁻, SO₄²⁻); deep-sea ferromanganese nodules (S⁰); and geologic materials (S²⁻, SO₄²⁻).

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