• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 258
  • 79
  • 39
  • 13
  • 9
  • 6
  • 5
  • 5
  • 3
  • 3
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 501
  • 232
  • 102
  • 56
  • 52
  • 51
  • 49
  • 49
  • 46
  • 44
  • 41
  • 41
  • 39
  • 37
  • 35
  • 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

Comportamento da extracao de ions metalicos em meio carbonato, por n-benzoilfenilhidroxilamina-benzeno. Aplicacao a determinacao de elementos tracos em uranio

CIPRIANI, MOACIR 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:17Z (GMT). No. of bitstreams: 1 00426.pdf: 1108368 bytes, checksum: 07f3d4698c9590abf2d11efd1657f4bf (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
12

The reactions of osmium (VIII) in hydroxide medium

Geswindt, Theodore Earl January 2009 (has links)
Spectrophotometric techniques were used to elucidate the discrepancies surrounding the reduction of osmium tetroxide by several primary alcohols in a hydroxide matrix. In contrast to the documented literature, this reaction was observed to occur in two consecutive reaction steps. Geometrical and computational analysis of kinetic data revealed that the reaction proceeds by the following reaction model: Os(VIII) + RCH2OH Os(VI) + RCHO Os(VIII) + Os(VI) Os2(VII) k1 k+2 k-2 The conditional rate constants and molar extinction coefficients were calculated using custom written software. A hydride transfer mechanism, coupled with the synchronous removal of the hydroxyl proton of the alcohol, was postulated. The complexation between osmium(VIII) and osmium(VI) was investigated. Mole ratio titrations and mole fraction plots show that at pH 14.3 a 1:1 complexation occurs between osmium(VIII) and osmium(VI). The equilibrium constants and molar extinction coefficients calculated by these methods were found to be consistent with the parameters obtained from the reduction of osmium tetroxide by primary alcohols at pH 14.3. The formation of a mixed oxidation state dimeric osmium complex (denoted Os2(VII)) has been proposed. Key words: Spectrophotometric techniques, osmium tetroxide, osmium(VIII), primary alcohols, osmium(VI).
13

A spectrophotometric study of the gold(III)-5-(p-ethoxyanilino)- 5, 6-dihydrouracil chelate

Marshall, Delbert Allan. January 1965 (has links)
Call number: LD2668 .T4 1965 M36 / Master of Science
14

An investigation of free radical involvement in cell death in a cell culture model of ischaemia

Johnston, Andrew January 1999 (has links)
No description available.
15

Factors involved in the Spectrophotometric analysis of fats

Potter, George Christian. January 1949 (has links)
LD2668 .T4 1949 P62 / Master of Science
16

Determination of formaldehyde in food by spectrophotometry and ion interaction chromatography.

January 1993 (has links)
by Ho Wai-ngan Sandra. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 197). / ACKNOWLEDGMENT / ABSTRACT / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / REFERENCES --- p.8 / Chapter CHAPTER 2 --- BRIEF REVIEW OF THE ANALYTICAL METHOD FOR THE DETERMINATION OF FORMALDEHYDE --- p.9 / Chapter 2.1 --- REVIEW OF SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF FORMALDEHYDE --- p.9 / Chapter 2.2 --- REVIEW OF CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF FORMALDEHYDE --- p.13 / Chapter 2.3 --- BASIC PRINCIPLES --- p.17 / REFERENCES --- p.20 / Chapter CHAPTER 3 --- SPECTROPHOTOMETRIC DETERMINATION OF FORMALDEHYDE --- p.21 / Chapter 3.1 --- INTRODUCTION --- p.21 / Chapter 3.2 --- EXPERIMENTAL --- p.24 / Chapter 3.3 --- RESULT AND DISCUSSION --- p.29 / Chapter 3.4 --- CONCLUSION --- p.58 / REFERENCES --- p.59 / Chapter CHAPTER 4 --- EFFECT OP COUNTER ANIONS AND CO-ANIONS IN ION INTERACTION CHROMATOGRAPHY --- p.60 / Chapter 4.1 --- INTRODUCTION --- p.60 / Chapter 4.2 --- EXPERIMENTAL --- p.73 / Chapter 4.3 --- RESULTS AND DISCUSSION --- p.78 / Chapter 4.4 --- CONCLUSION --- p.150 / REFERENCES --- p.151 / Chapter CHAPTER 5 --- CHROMATOGRAPHIC DETERMINATION OF FORMALDEHYDE --- p.153 / Chapter 5.1 --- INTRODUCTION --- p.153 / Chapter 5.2 --- EXPERIMENTAL --- p.154 / Chapter 5.3 --- RESULTS AND DISCUSSION --- p.158 / Chapter 5.4 --- CONCLUSION --- p.187 / REFERENCES --- p.188 / "APPENDIX OCCURENCE, TOXICOLOGY & BIOCHEMISTRY OF FORMALDEHYDE" --- p.188 / Chapter A1 --- INTRODUCTION --- p.188 / Chapter A2 --- OCCURENCE --- p.188 / Chapter A3 --- BIOCHEMISTRY --- p.192 / Chapter A4 --- TOXICOLOGY --- p.193 / REFERENCES --- p.197 / LEGENDS FOR FIGURES / LEGENDS FOR TABLES
17

Identification and quantitative determination of tetracyclines in pharmaceutical preparations by derivative spectrophotometry.

January 1990 (has links)
Fung Wai-kwong. / Thesis (M.Phil)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 86-88. / ACKNOWLEDGEMENT / ABSTRACT --- p.1 / Chapter PART I. --- INTRODUCTION --- p.3 / Chapter 1.1 --- General introduction --- p.3 / Chapter 1.2 --- Brief review of the derivative --- p.5 / spectrophotometric method / Chapter PART II. --- IDENTIFICATION OF TETRACYCLINES --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Experimental --- p.14 / Chapter 2.3 --- Results and discussion --- p.16 / Chapter 2.4 --- Conclusion --- p.20 / Chapter PART III. --- QUANTITATIVE DETERMINATION OF TETRACYCLINES AND RELATED DRUGS --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Experimental --- p.30 / Chapter 3.3 --- Results and discussion --- p.38 / Chapter 3.4 --- Conclusion --- p.82 / References --- p.86
18

Colorimetric methods for the determination of carbon monoxide in air

Wiens, Robert Elmer January 2010 (has links)
Digitized by Kansas Correctional Industries
19

Rates of superoxide anion radical reaction with alkyl bromides

Warner, Richard Jay, 1952- January 2011 (has links)
Vita. / Digitized by Kansas Correctional Industries
20

Lead, zinc, and copper (II) complexes of 4-(2-pyridylazo)-resorcinol in aqueous solution : their identification, stability and spectrophotometric titration

Rosales Hoz, Ma T. Leticia January 1975 (has links)
No description available.

Page generated in 0.0768 seconds