Loblolly pine growth increments were divided into five fractions; two earlywood a transition and two latewood growth zones. Each growth zone was analyzed for lignin, extractives, and carbohydrate content. Each fraction was digested to four different time schedules using kraft pulping process. All other cooking variables were held constant. A total of twenty pulps were prepared. Significant differences were observed in pulp yields between intra-incremental growth zones. For the longer digestion times, fraction 1, the early springwood, produced pulp yields greater than the remaining four growth zones. For the shorter digestion periods, fractions 1, 4 and 5 showed comparable pulp yields. For a given cooking time, fraction 2 produced the lowest pulp yield. Pulp yields were shown to be dependent on cellulosic material found in the whole wood. The unusually high pulp yields for fraction 1 were explained on the basis of high level of resistance of carbohydrates to chemical degradation in that zone. Responses to refining and papermaking properties were investigated from the partitioned growth zones. For the four digestion series, fraction 2 refined the slowest followed by fractions 1 and 3 and then fractions 4 and 5. Differences in refining characteristics were defined in terms of Canadian standard freeness and explained on the basis of differences in fiber morphology and residual lignin content in the pulps. Significant differences were observed in the physical and mechanical properties of paper produced from the twenty pulps. The results showed that for a given digestion series, fraction 2, the late springwood zone, produced paper with superior tensile strength but with inferior bulk and tear properties. The opposite trends were observed for fractions 4 and 5, the latewood zones. Fractions 1 and 3 showed intermediate sheet properties as compared to the other growth zones. Differences in sheet properties were explained on the basis of difference in fiber properties for the intra-increment growth zones. Sheet properties were shown to be dependent on digestion time or residual lignin content remaining in the pulps. For all intra-increment pulps, tensile properties increased whereas bulk and tear properties decreased as digestion time increased. Carbohydrate removal influenced sheet properties due to its apparent influence on fiber flexibility. Insignificant differences in sheet properties were observed when compared at identical sheet densities. Differences in tensile strength properties were related to inherent characteristics of individual fibers. It was shown that the number of fibers per unit volume of paper is the most important attribute to strength. Of secondary importance is the strength of the individual fiber-to-fiber bonds which is influenced by residual lignin in the pulp. Using tensile energy values, the number of hydrogen bonds active in resisting tensile forces was estimated. This number was also related to the number of fibers per unit volume as well as to the residual lignin. All the above variables could be explained on the basis of intra-increment chemical and anatomical properties of wood. / Ph. D.

The study falls in the area of random equations; in particular properties of random matrices have been studied. The dissertation makes precise some statistical theories of spectra developed in recent years by a number of physicists. Two basic results have been achieved. The first result is a characterization of the distribution of a symmetric random matrix. Assuming independence of the diagonal and super-diagonal random variables of the symmetric random matrix the following theorem is proved: the distribution of the matrix is invariant under orthogonal similarity transforms if and only if the diagonal random variables are normally distributed with mean μ, and variance 2a², and the off-diagonal elements are normally distributed with mean O and variance a², :for some constants μ, and a² > O. The proof is achieved by solving a functional equation in characteristic functions. This seems to have been first proved in this context by Porter and Rosenzweig (Ann. Acad. Sci. Fennicae. AVI, No. 44, 1960) by a different method and under more restrictive conditions than those given here. The second result deals with the asymptotic distribution of eigenvalues of a synnnetric random matrix as the dimension approaches infinity. Let A_n be an appropriately normalized n ⨉ n symmetric random matrix and let W_n(x) denote the empirical distribution function of the eigenvalues of A<sub>n</sub. Under suitable conditions on the random variables of the matrix it is proved that W_n(x)⟶W(x) as n∞, where W is the absolutely continuous distribution function with a semi-circle density, W(x) = { ⎧ 2/π (1-x²)^1/2, |x| ≤ 1 ⎨ ⎩ 0 , |x| > 1. The proof is achieved by an intricate combinatorial analysis in conjunction with the method of moments. This result extends a conjecture made by E. P. Wigner ("On the Distribution of the Roots of Certain Symmmetric Matrices," Ann. Math. 67, 1958, 325). / Ph. D.

Because of the allegorical nature of much of Hawthorne’s work, it is appropriate to discover symbolism in the author's selection of given names and surnames for his characters. Name symbolism includes both sound and meaning of names or parts of names. Symbolic naming is defined as that technique through which a character's name, straightforwardly or ironically, reveals his inner nature and his relationship to other characters. This revelation, in turn, serves to underscore thematic points in the works. In Hawthorne’s five finished novels, there are at least four distinct sources for the symbolic names of characters; there are actual historical names, Biblical, classic, or literary names, common foreign or provincial names, and names probably original with Hawthorne. There are, of course, frequent combinations of these sources. In this investigation into Hawthorne’s use of name symbolism in the five finished novels, it will be noted that the technique is closely related to the degree of development of a character. The closer a character comes to being a purely symbolic character, the more obvious is the name; conversely, the more individualized the character, the more subtle and ambiguous is the name. This thesis analyzes the names of all the characters in <i>Fanshawe</i>, <i>The Scarlet Letter</i>, <i>The House of the Seven Gables</i>, <i>The Blithedale Romance</i>, and <i>The Marble Faun</i>, in that order, and attempts to show that an understanding of the symbolic meaning of characters’ names can be helpful in leading the reader to a more thorough comprehension of Hawthorne's characters and themes. / M.A.

The objectives of the present investigation were: (1) to explore an area, root exudation of peanuts, in which no previous work has been reported; (2) to study the effects of O₂ and CO₂ tensions, both individually and combined, on peanut root exudation; and (3) to determine quantitatively the sugars exuded from the roots of peanut plants grown under gnotobiotic conditions. Seed from the peanut plant, Arachis hypogaea, L. var. NC-2 was used, Peanut embryos, with the cotyledons removed, were surface sterilized; placed aseptically into sterile plexiglass isolator chambers; and planted in vermiculite saturated with Hoagland and Arnon nutrient solution contained within transplanting tubes. Because of slow embryo and seedling growth without the cotyledons, plants were not transplanted into 500 ml flasks until after 90 days. Three separate experiments were conducted. In all three, N₂ gas was metered to the roots of six plants in each of two isolator chambers. In addition, in the first study, roots of six plants in each of two isolator chambers received a gas mixture composed of 21% O₂, 10% CO₂, and 69% N₂; in the second study, they received a gas mixture composed of 21% O₂ and 79% N₂; and in the third study, they received a gas mixture composed of 10% CO₂ and 90% N₂. Duration of each experiment was 6 wks. Samples consisting of nutrient solution containing peanut root exudates from three plants were collected every 2 wks. Peanut plants were harvested and fresh weights, dry weights, and lengths of both shoots and roots (separate) were obtained. Root exudate analysis consisted of filtration to remove insoluble materials, flash evaporation to reduce the volume, salt removal by cation and anion exchange resins, freeze-drying, thin-layer chromatography to separate and identify the various sugars, and densitometry to obtain the quantity of each sugar. Analysis of variance showed for all adjusted harvest valves no significant difference as a result of treatment or replication at the 5% level. For all measured growth parameters, Duncan's multiple range test showed no significant differences within replicates caused by treatment. Five sugars, galactose; mannose; xylose; ribose; and dihydroxyacetone, were identified in peanut root exudates. Galactose was present in all 72 root exudate samples, dihydroxyacetone in 69, ribose in 33, mannose in 8, and xylose in 5. Analysis of variance showed a significant difference at the 20% level in the total amount of galactose exuded as a result of treatment and a significant difference at the 25% level in the amount of galactose exuded as a result of plant age. These results are indicative of consistent trends which need further investigation. Duncan's multiple range test showed an interaction between treatment and time which was significant at the 5% level. Young plants (2 wks old) showed a significantly greater amount of galactose exuded under aerobic conditions. As the plants matured (4 and 6 wks old) there was a trend toward greater amounts of galactose exuded under anaerobic conditions than under aerobic. Analysis of variance showed no significant differences at the 25% level in the total amounts of dihydroxyacetone exuded as a result of treatment and no significant difference at the 25% level in the amounts of dihydroxyacetone exuded as a result of plant age. These results are indicative of consistent trends which need further investigation. Duncan's multiple range test showed in young plants (2 wks old) a Significantly greater amount of dihydroxyacetone exuded under aerobic conditions at the 5% level. As the plants matured (4 and 6 wks old) there was a trend toward greater amounts of dihydroxyacetone exuded under anaerobic than under aerobic conditions. / Ph. D.

A study was made to determine the effects of fillers on the mechanical properties of a flexible polyester resin. Also, a method was demonstrated for a constrained optimization of the volumetric cost of the filled polyester. The fillers investigated included clay, marble, nut shell flour, and glass beads and microspheres. Mechanical property data were generated for different filler concentrations and particle sizes. The properties tested were density, tensile strength, ultimate elongation, secant modulus, and flexural strength. Testing was performed according to standard methods using an Instron Universal Testing Machine with strain gage. Contrary to the results of previous investigators, rigid particulate fillers (e.g., clay, marble, and nut shell flour, excluding glass beads and microspheres) significantly increased the tensile strength of the resin. Increases in flexural strength were observed for certain fillers. Both tensile and flexural strength improvements were greater for smaller particles than for larger ones. The fillers increased the modulus and decreased the ultimate elongation of the resin. The method of optimization included an experimental design to generate data and a polynomial regression analysis to determine the mechanical property constraint functions. The constraints were well approximated by linear functions, and linear programming was used to find an optimum. The linear functions could also be used to give a reasonable approximation of the mechanical property constraints outside the experimental region. / M.S.

Modern day control systems, utilizing a digital computer, contain samplers as well as linear and nonlinear elements. State space techniques are the best means for analyzing systems of this type. SAMP (State Analysis Modeling Program, SAMPler), a digital computer program, uses these techniques in order to provide the following: 1. SAMP is capable of analyzing a system containing integrators, summing junctions, fixed gain terms, samplers, and a variety of nonlinearities. 2. Samplers can be the zero order hold type or the finite width type. They can operate at different rates. 3. A novel feature of this program is utilizing a high speed sampler for simulation of nonlinearities. 4. SAMP's inputs are essentially the matrices required for a state space analysis. They include the system coefficient matrix (A), the state transition matrix (B), the initial state vector (W), and a novel specification matrix (C). S. The program contains built in diagnostics designed to aid the user troubleshoot his program setup. 6. Primary program output is a print/plot of any state variable versus time. If selected the status of all state variables versus time will be printed. 7. SAMP contains a built in example designed to aid the user understand program operation. / M.S.

In recent years, statistical theory has become widely used in the study of reliability. In this study, we shall consider two types of estimators, namely, the Bayes and minimum variance unbiased estimators for the scale parameter θ in the truncated Weibull life testing model when the shape parameter ρ assumed known. In addition, we shall estimate the corresponding reliability function of the above estimators. The first type of estimator of θ and the reliability function we will consider is the Bayes estimator using the general uniform, exponential, and inverted gamma distributions as prior probability density functions for the parameter θ, We shall also derive the minimum variance unbiased estimator (MVUE). For each prior probability density function, the Bayes estimator is compared with the MVUE by Monte Carlo simulation. Also, the Bayes estimators for a given prior density of θ are compared with the results of Canavos and Tsokos [5]. Their model was the Weibull probability density function with guaranteed time τ. / M.S.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

In order to develop further a comprehensive characterization of spirilla and to devise a more satisfactory classification of the species, the type strains of 20 marine and fresh-water species of the genus Spirillum, plus additional strains of S. gracile, S. itersonii, S. serpens, and S. volutans, and 6 un-named strains of spirilla, were subjected to over 90 physiological tests and also various morphological tests using standardized inocula, media, incubation times, and testing methods. Determination of DNA base compositions was also performed. All strains of spirilla grew aerobically except S, volutans which was an obligate microaerophile; S. giesbergeri and S. gracile appeared to be possible facultative rnicroacrophiles, S. lunatum and S, itersonii were the only species to. grow anaerobically in the presence of nitrate, The optimum temperature was 30 C for all strains examined. The cell diameters for all strains formed an almost continuous spectrum, ranging from 0.25 to 1.7 microns. All spirilla were actively motile and a number of the strains possessed flagellar tufts visible with living cells by dark field microscopy and in the case of S. volutans also by phase contrast. Coccoid bodies were present in 4 week cultures in the case of most marine strains; only 3 fresh-water species exhibited these forms, Several physiological characteristics were found to be uniformly or nearly uniformly positive (oxidase, deaminase activity with peptone, catalase, phosphatase, HzS from cysteine, growth in 1% bile) or negative (indol; amylase; sulfatase; hydrolysis of gelatin, casein, aesculin, and hippurate; urease; alkaline reaction in litmus milk; acid reaction from carbohydrates) for all or nearly all of the strains, In the few cases where acid was produced from carbohydrates, a reduced peptone concentration was necessary. Several physiological characteristics yielded varied reactions among the spirilla (reduction of selenite and nitrate; growth on EMB, MacConkey, TSI, and Seller's agars and in MRVP broth; RNAase and DNAase activity; and tolerance to 1% glycine}. Water-soluble pigments were produced by a few strains growing on aromatic amino acids. Three percent NaCl inhibited all fresh-water strains, while the marine strains could all grow in the presence of 9. 75% (w/v) NaCl. The DNA base compositions of the spirilla, determined from their Tm values, gave a broad range of values from 38 to 65 moles % G + C. The limits of genus and species variation, the usefulness of standardized conditions in characterizing strains of spirilla, discrepancies arising from a comparison of the present data with earlier results, the division of the genus Spirillum on the basis of single, highly-weighted characters, and the division of genus Spirillum on the basis of correlated characters, were discussed. A modified description of the genus Spirillum (Ehrenberg, 1830) based on the present study was presented. Various physiological tests important for species differentiation were indicated. A modified classification scheme for the species of genus Spirillum was devised, and a temporary diagnostic key was also presented. / Ph. D.