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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

The effect of pressures below one atmosphere on the performance of a packed column

Daniel, Leonard Rupert 08 1900 (has links)
No description available.
2

An empirical relationship between reflux ratio and the number of equilibrium plates in fractionating columns

Brown, George Granger, Martin, Homer Zettler, January 1900 (has links)
H.Z. Martin's Thesis (Ph. D.)--University of Michigan, 1938. / Cover title. "This paper is in reality an elaboration of the discussion by Dr. G.G. Brown of the paper 'Graphical solution of problems in multicomponent fractionation.' by F.J. Jenny, presented at the Akron meeting of the Institute."--Foot-note, p. 679. "Reprinted from Transactions of American institute of chemical engineers, vol. 35, no. 5, October 25, 1939." "Literature cited": p. 708.
3

Studier over fraktioneret destillation med saerligt henblik paa diskontinuerlig fraktionering With a summary in English.

Klit, Andreas, January 1943 (has links)
Thesis--Copenhagen.
4

Studier over fraktioneret destillation med saerligt henblik paa diskontinuerlig fraktionering With a summary in English.

Klit, Andreas, January 1943 (has links)
Thesis--Copenhagen.
5

An empirical relationship between reflux ratio and the number of equilibrium plates in fractionating columns

Brown, George Granger, Martin, Homer Zettler, January 1900 (has links)
H.Z. Martin's Thesis (Ph. D.)--University of Michigan, 1938. / Cover title. "This paper is in reality an elaboration of the discussion by Dr. G.G. Brown of the paper 'Graphical solution of problems in multicomponent fractionation.' by F.J. Jenny, presented at the Akron meeting of the Institute."--Foot-note, p. 679. "Reprinted from Transactions of American institute of chemical engineers, vol. 35, no. 5, October 25, 1939." "Literature cited": p. 708.
6

Distillation studies ...

Geniesse, John Collin, Leslie, Eugene H. January 1926 (has links)
Thesis (Ph. D.)--University of Michigan, 1924. / Reprinted from an article by E.H. Leslie and J.C. Geniesse, published in Industrial and engineering chemistry, v. 18, no. 6, June, 1926.
7

Plate efficiencies in fractional distillation

Beyer, Gerhard H. January 1949 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1949. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [79]-80).
8

The Dynamic Foundation of Fractal Operators.

Bologna, Mauro 05 1900 (has links)
The fractal operators discussed in this dissertation are introduced in the form originally proposed in an earlier book of the candidate, which proves to be very convenient for physicists, due to its heuristic and intuitive nature. This dissertation proves that these fractal operators are the most convenient tools to address a number of problems in condensed matter, in accordance with the point of view of many other authors, and with the earlier book of the candidate. The microscopic foundation of the fractal calculus on the basis of either classical or quantum mechanics is still unknown, and the second part of this dissertation aims at this important task. This dissertation proves that the adoption of a master equation approach, and so of probabilistic as well as dynamical argument yields a satisfactory solution of the problem, as shown in a work by the candidate already published. At the same time, this dissertation shows that the foundation of Levy statistics is compatible with ordinary statistical mechanics and thermodynamics. The problem of the connection with the Kolmogorov-Sinai entropy is a delicate problem that, however, can be successfully solved. The derivation from a microscopic Liouville-like approach based on densities, however, is shown to be impossible. This dissertation, in fact, establishes the existence of a striking conflict between densities and trajectories. The third part of this dissertation is devoted to establishing the consequences of the conflict between trajectories and densities in quantum mechanics, and triggers a search for the experimental assessment of spontaneous wave-function collapses. The research work of this dissertation has been the object of several papers and two books.
9

Numerical solution of fractional differential equations and their application to physics and engineering

Ferrás, Luís J. L. January 2018 (has links)
This dissertation presents new numerical methods for the solution of fractional differential equations of single and distributed order that find application in the different fields of physics and engineering. We start by presenting the relationship between fractional derivatives and processes like anomalous diffusion, and, we then develop new numerical methods for the solution of the time-fractional diffusion equations. The first numerical method is developed for the solution of the fractional diffusion equations with Neumann boundary conditions and the diffusivity parameter depending on the space variable. The method is based on finite differences, and, we prove its convergence (convergence order of O(Δx² + Δt²<sup>-α</sup>), 0 < α < 1) and stability. We also present a brief description of the application of such boundary conditions and fractional model to real world problems (heat flux in human skin). A discussion on the common substitution of the classical derivative by a fractional derivative is also performed, using as an example the temperature equation. Numerical methods for the solution of fractional differential equations are more difficult to develop when compared to the classical integer-order case, and, this is due to potential singularities of the solution and to the nonlocal properties of the fractional differential operators that lead to numerical methods that are computationally demanding. We then study a more complex type of equations: distributed order fractional differential equations where we intend to overcome the second problem on the numerical approximation of fractional differential equations mentioned above. These equations allow the modelling of more complex anomalous diffusion processes, and can be viewed as a continuous sum of weighted fractional derivatives. Since the numerical solution of distributed order fractional differential equations based on finite differences is very time consuming, we develop a new numerical method for the solution of the distributed order fractional differential equations based on Chebyshev polynomials and present for the first time a detailed study on the convergence of the method. The third numerical method proposed in this thesis aims to overcome both problems on the numerical approximation of fractional differential equations. We start by solving the problem of potential singularities in the solution by presenting a method based on a non-polynomial approximation of the solution. We use the method of lines for the numerical approximation of the fractional diffusion equation, by proceeding in two separate steps: first, spatial derivatives are approximated using finite differences; second, the resulting system of semi-discrete ordinary differential equations in the initial value variable is integrated in time with a non-polynomial collocation method. This numerical method is further improved by considering graded meshes and an hybrid approximation of the solution by considering a non-polynomial approximation in the first sub-interval which contains the origin in time (the point where the solution may be singular) and a polynomial approximation in the remaining intervals. This way we obtain a method that allows a faster numerical solution of fractional differential equations (than the method obtained with non-polynomial approximation) and also takes into account the potential singularity of the solution. The thesis ends with the main conclusions and a discussion on the main topics presented along the text, together with a proposal of future work.
10

Novel Fractional Wavelet Transform with Closed-Form Expression

Anoh, Kelvin O.O., Abd-Alhameed, Raed, Jones, Steven M.R., Ochonogor, O., Dama, Yousef A.S. 08 1900 (has links)
Yes / A new wavelet transform (WT) is introduced based on the fractional properties of the traditional Fourier transform. The new wavelet follows from the fractional Fourier order which uniquely identifies the representation of an input function in a fractional domain. It exploits the combined advantages of WT and fractional Fourier transform (FrFT). The transform permits the identification of a transformed function based on the fractional rotation in time-frequency plane. The fractional rotation is then used to identify individual fractional daughter wavelets. This study is, for convenience, limited to one-dimension. Approach for discussing two or more dimensions is shown.

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