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Synthetic studies on chaksine
Full text linkThis thesis is concerned with the preliminary studies in the
synthesis of a monoterpenoid alkaloid, chaksine.
Diethyl methylmalonate was alkylated with 1,3-dibromo propane
to give 2-(3-bromopropyl)-2-methylmalonate. Hydrolysis and decarboxylation
of this product gave the mono acid which was then converted to
the corresponding ethyl ester. Reduction with lithium borohydride
yielded the primary alcohol to which a tetrahydropyran protective group
was added. Alkylation with diethyl malonate followed by acylation with
the mixed anhydride of isovaleric acid and carbobenzyloxyglycine gave
diethyl (see document for formula)
Books and readers, 1594; a survey and analysis of all books printed in England or in English abroad during the year 1594
Full text linkElectrical conduction in nylon fibre and cellulosic capacitor tissue
Full text linkThe experiments described in this work are divided into two main
parts. The first is concerned with electrical properties of a
single filament of nylon held between two tungsten hook-electrodes.
Currents were observed in atmospheres of different relative humidities and attempts were made to determine the voltage distribution
along the filament. The voltage measurements were made using
a high-impedence electrostatic null detector with a potentiometer
system for balancing. The results were not highly reproducible
and no definite conclusions could be made.
The second part deals with currents through capacitor tissue in a
metal- insulation- metal sandwich arrangement. A time-dependent
polarization was observed and is discussed along with methods for
determining an acceptable value for the steady-state current. Some
attempts are made to apply Poole-Frenkel theory since there is a
certain quantitative agreement with experiment. Current-temperature
observations indicated that the activation energy is about 1 ev.
Conclusions concerning the mechanism of conduction are suggested on
the basis of available theory
Non-standard analysis / by Geraldine S. Service
Full text linkThis thesis is a study of several theories of Non-standard Analysis.
Particular attention is paid to the theories presented by A. Robinson
and E. Zakon.
Chapter I contains background information from Mathematical Logic
and leads to the definition of a Non-standard Model of Analysis.-
In Chapter II, we develop the direct product, the ultraproduct and
the reduced ultraproduct of a set of similar structures and "construct"
a non-standard model of analysis in the form of a reduced ultrapower of
the set of real numbers. This model contains genuine "infinite" and
"infinitesimal" elements which behave like those which we informally
think of in classical analysis.
Chapter III contains the theory of Professor Abraham Robinson for
first order structures and languages. The Finiteness Principle is
applied in the proof of,the existence of Non-standard Models of Analysis.
Chapter IV contains the theory of Non-standard Analysis presented
by Professor Elias Zakon. This is the main chapter in the paper. His
set-theoretical approach is based on the notion of a superstructure which
contains all of the set—theoretical "objects" which exist on a set of
individuals. A monomorphism is a one-to-one mapping from one superstructure into another superstructure which preserves the validity of sentences.
The existence of monomorphisms is proven using ultrapowers. A Non-standard
Model of Analysis is defined in terms of a monomorphism. This definition
parallels the one given in Chapter I. In Chapter V we define and prove the existence of an Extra-standard
Model of Analysis, a concept which is similar to that of a Non-standard
Model of Analysis. We also present Professor Robinson's theory for
higher order structures and languages. We compare the theories presented
by Professors Robinson and Zakon along with ;:hat of Professor M. Shimrat
Laurier and the Liberal Party, 1916-1919.
Full text link1969This thesis is an analysis of Laurier's leadership of the Liberal Party during the years 1916-1919
Metrization and sigma bases
Full text link1969In this thesis, we use the concept of sigma base to study the metrizability of various topological spaces. Chapter 1 is devoted to the definition of basic terms, a proof of Urysohn's Metrization Theorem, and an introduction to sigma structures
Acoustoelectric effect in semiconductors
Full text linkThe possibility of electron temperature decreasing below
the lattice temperature in the presence of an external electric field
(electron cooling) has been pointed out by Paranjape and Ambrose (1964).
In the present works we show that under suitable conditions an external
sound wave may produce the phenomenon of electron cooling in a semiconductor.
We have shown that a decrease in electron temperature may occur
when (1) the electrons are predominantly scattered by optical polar or
non-polar optical modes of the lattice vibrations and (2) when the incident
sound wave energy flux is greater than a certain critical value
WQ (which depends on the type of semiconductor). Chapter I consists of
a description of the model and a brief outline,of the calculations. In
Chapter II, using a displaced Maxwellian function, we have calculated
the rates of energy and momentum transfer from the electrons to the lattice
for acoustical, optical polar and non-polar optical types of scattering.
The rates of energy and momentum transfer from the sound wave
to the electrons are calculated in Chapter II, Section (2.b,l). Using
these rates in conservation conditions (1.11) and (1.12), we obtain the
expression for the electron temperature T as a function of the energy
flux W (Eqn. (3.6)). Inequality conditions (3.7) and (3.8) are the main
results of our calculations. Condition (3.7) is equivalent to the electron
cooling condition obtained by Paranjape and de Alba (1965) in the
case of an electric field, while (3.8) gives the minimum sound wave energy
flux P/Q required to produce electron cooling. In non-polar and polar substances, the required predominance of optical scattering over
acoustical scattering is expressed by the ratios (see document for formula)
in Eqns. (3.24) and (3.30), respectively. In Sections (S.b.l) and
(3.b.2), v/e have obtained the expressions for the sound absorption
coefficient a and acoustoelectric current in terms of the energy
flux W
Some dielectric studies
Full text linkTwo methods of approach are current in the literature
for the interpretation of dielectric relaxation. One is that
due to Debye which assumes that the relaxation process has its
origin in the retardation of molecular reorientation due to
frictional forces acting on the molecule. The other treats
dipole rotation as a rate process in which the dipole must
acquire a certain amount of energy in order to surmount a
barrier separating two equilibrium positions of orientation.
The dielectric relaxation times of some large ketones have
been determined at four temperatures using a cell which does not
appear to have been used up to this time for measuring the
dielectric constant and loss of low loss liquids. The molecules
measured were selected because of their size and shape, five
were ellipsoidal and one was disc-like. For the ellipsoidal
molecules^ the position of the dipole within the molecule was
varied to investigate its effect on the relaxation time. A
number of equations, based on the Debye model, which attempt to,
account for the size of molecular relaxation time are examined.
It is found that only the Fischer equation is satisfactory in
predicting the effects of dipole direction within the molecule.
The experimentally measured activation energies for all
the large molecules were found to be similar and only a little
higher than those observed for smaller molecules. In an attempt
to understand these values a model is proposed based on the energy expended by the molecule during its reorientation process.
The approach leads to a method for predicting the effect of
solvent on dielectric relaxation time. It is found that the
relaxation time depends exponentially on the internal pressure
of the medium surrounding the relaxing species, and the
activation energy can be accounted for in terms of the product
of an activation volume and the internal pressure. From the
activation volume an estimate is obtained of the angle through
which the dipole rotates. For small molecules it is found that
the angle is of the order of 20 degrees which indicates a fairly
large jump accompanying the reorientation. For the larger
molecules, however, the angle is much smaller, hence, the behaviour
resembles Brownian rotational diffusion
A critical comparison of copies of the first three editions of Arden of Feversham
Full text link1968This critical comparison of copies of the first three editions of Arden of Feversham includes in the introduction a description of the text, sources and stage history, followed by an examination of the problems of dating and authorship. The genre of domestic tragedy also is investigated, according to its development and influence: i.e. the contributing factors of the preceding drama, its individual merits, and a general study of comparative drama. The criticism of the past and an independent evaluation of the play as a literary work are also presented