• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 128
  • 33
  • 17
  • 5
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 226
  • 46
  • 32
  • 29
  • 29
  • 21
  • 21
  • 17
  • 17
  • 14
  • 14
  • 13
  • 11
  • 11
  • 10
  • 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

The Strecker degradation and its relationship to flavour in cooked vegetables

Kirkpatrick, Joanna January 2001 (has links)
No description available.
12

The condensation of phenols with aromatic hydroxy-aldehydes /

Sousa, Julian Bernard. January 1953 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1953. / References: p.93-95. Type-written copy.
13

The condensation of phenols with deactivated aromatic aldehydes /

Mok, Sau-fun. January 1955 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1955. / References: p.102-106. Type-written copy.
14

The reactions between acid halides and aldehydes

Ulich, Lynne Herman, Adams, Roger, January 1900 (has links)
Abstract of Thesis (Ph. D.)--University of Illinois, 1920. / Biography. "Contribution from the Chemical laboratory of the University of Illinois." "Reprinted from the Journal of the American chemical society, vol. XLIII. no. 3. March, 1921." Caption title: The reaction between acid halides and aldehydes. III. By L.H. Ulich with Roger Adams.
15

The action of acid halides on aldehydes and ketones

Vollweiler, Ernest Henry, January 1900 (has links)
Thesis (Ph. D.)--University of Illinois, 1918. / Biography. "Reprinted from the Journal of the American chemical society, vol. XI., no. 11, p. 1732."
16

The condensation of 2-methylbutenal with citral ...

Walton, Henry M., January 1941 (has links)
Thesis (Ph. D.)--University of Chicago, 1938. / Reproduced from type-written copy. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." Includes bibliographical references.
17

The catalytic condensation of aldehydes to esters

Child, William Clark. January 1924 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1924. / Typescript. Witht his are bound 2 reprints from Journal of the American Chemical Society: The condensation of aldehydes to esters by aluminum ethoxide / By W.C. Child and Homer Adkins. vol. XLV, no. 12 (Dec. 1923), p. [3013]-3023.-- The condensation of aldehydes to esters by alkoxides / By W.C. Child and Homer Adkins. vol. XLVII, no. 3 (Mar. 1925), p. [798]-807. Includes bibliographical references.
18

The photochemistry of aldehydes in the gaseous phase

Sifniades, Stylianos January 1962 (has links)
The object of the present work was the investigation of two separate topics, the investigation of the radical-radical termination step in the photochemical oxidation of acetaldehyde and the investigation of the photolysis of crotonaldehyde, both in the gas phase and at room temperature. A third topic, the photolysis of 3-butene-1-al, was investigated in the course of the work, in order to provide evidence in favour of the mechanism proposed for the photolysis of crotonaldehyde. In the first part of the work, mixtures of acetaldehyde and isotopically enriched oxygen containing argon as a reference gas were irradiated at 25°C with light at a wavelength of 3130 [formula omitted] and the reaction products were analyzed by gas chromatography and mass spectrometry. The major products were found to be peracetic acid and diacetyl peroxide. By following the rate of formation of these products, as well as the concentrations of the three possible kinds of oxygen in the reaction mixture, it was possible to verify McDowell and Farmer's mechanism for the photooxidation of acetaldehyde and establish a satisfactory mechanism for the chain terminating step of the reaction. In the second part of the work, crotonaldehyde was irradiated at 30°C with light at a wavelength of 2450-4000 [formula omitted], and the products analyzed by gas chromatography and infra-red spectroscopy. The only product in experiments of short duration was found to be 3-butene-1-al, thus establishing isomerization as the primary process of the reaction. In later stages CO, propylene and 1,5-hexadiene were formed. The following experimental laws were found to hold for the rate of formation of these products: d(3-butene-1-al)/dt = ႴIabs , Ⴔ = 0.095 ± 0.005 d(1, 5-hexadiene)/dt ∼ (Iabs².t)/(crotonaldehyde ) d(propylene )/dt ∼ (Iabs².t)/(crotonaldehyde)1.3-1.5 No detailed law was established for the rate of formation of CO, but whenever measured it was found to follow closely the propylene formation. These experimental laws were interpreted by means of a mechanism, in which crotonaldehyde participates in so far as it isomerizes to 3-butene-1-al. The latter was assumed to yield the three other products of the reaction through a mixed radical-molecular photochemical dissociation. Evidence was provided in favour of the proposed mechanism by studying the photolysis of 3-butene-1-al at 30°C and a wavelength of 2450-4000 [formula omitted]. The products of the reaction were found to be propylene, 1,5-hexadiene and CO, with their rates of formation obeying the following laws: d(1,5-hexadiene)/dt = Ⴔhexad. Iabs , Ⴔhexad = 0.135 ± 0.0318 d(propylene)/dt = Ⴔprop‧Iabs , Ⴔprop = 0.79 ± 0.05 CO formation was found to be approximately equal to propylene formation. These experimental laws were interpreted by means of a mixed radical-molecular photochemical dissociation of 3-butene-1-al, thus justifying the mechanism proposed for the photolysis of crotonaldehyde. / Science, Faculty of / Chemistry, Department of / Graduate
19

The catalytic decarbonylation of aldehydes using iron porphyrin complexes

Belani, Ramesh January 1985 (has links)
The aim of this project was to investigate the use of iron porphyrin complexes as potential homogeneous catalysts for the decarbonylation of aldehydes. Complexes of the type Fe(TPP)L₂ (where L = n-Bu₃P, PPh₃ or piperidine) were prepared and reacted with CO gas, or with aldehydes as sources of CO. Since the loss of coordinated CO from the Fe(TPP)(CO)(n-Bu₃P) complex was more facile, the bis(n-Bu₃P) phosphine system was studied in more detail. The X-ray structure of FeTPP(n-Bu₃P)₂ Is described, and this includes the first determination of an FeII-P bond distance for a metalloporphyrin. The study using Fe(TPP)L₂ complexes as decarbonylation catalysts was somewhat hindered by the extreme air-sensitivity of the porphyrin complexes in solution. UV/visible spectroscopy and gas chromatography were used to monitor the decarbonylation reactions. The reaction mixtures were analysed by GC/MS. The decarbonylation reactions were characterised by inconsistent turnover numbers and lack of reproducibility; during the decarbonylation of phenylacetaldehyde, bibenzyl was detected. Such factors are indicative of a free radical mechanism, similar to that proposed earlier for related Ru(II) porphyrin systems. The carbonylation of FeTPP(n-Bu₃P)₂ by CO gas was of interest with respect to the catalytic reaction, which must involve formation of a carbonyl complex. The reaction, FeTPP(n-Bu₃P)₂ + CO K [mathematical formula omitted] FeTPP(n-Bu₃P)(CO) + n-Bu₃P was found to have a K value of 0.72 at 29°C, while the temperature dependence of K was studied to obtain the thermodynamic parameters ΔS and ΔH for the equilibrium. / Science, Faculty of / Chemistry, Department of / Graduate
20

The vapor phase photolysis of (+)2-methylbutanal /

Gruver, Jerry Thompson January 1957 (has links)
No description available.

Page generated in 0.0367 seconds