Showing papers by "University of Florida published in 1968"

Low-Frequency Component Electric Microfield Distributions in Plasmas

Abstract: Low-frequency component electric microfield distributions in a plasma are calculated at both a neutral and a charged point. It is shown that this calculation allows for the inclusion of all correlations to a high degree of accuracy. The theory is compared with the Holtsmark and Baranger-Mozer theories. A detailed analysis of all approximations is included, together with a Monte Carlo study. Numerical results are shown both graphically and in tabulated form.

Studies in perturbation theory XIII. Treatment of constants of motion in resolvent method, partitioning technique, and perturbation theory

Abstract: After a brief survey of some basic concepts in the theory of linear spaces, the eigenvalue problem is formulated in the resolvent technique based on the introduction of a reference function φ and a complex variable ℰ This leads to a series of fundamental concepts including the trial wave function, the inhomogeneous equation, and finally the transition and expectation values of the Hamiltonian, of which the former renders a “bracketing function” for the energy In order to avoid the explicit limiting procedures in this approach, the eigenvalue problem is then reformulated in terms of the partitioning technique which, in turn, leads to a closed form of infinite-order perturbation theory The eigenvalue problem is greatly simplified if the Hamiltonian H has a constant of motion Λ or has symmetry properties characterized by the group G = {g}, and the question is now how these simplifications can be incorporated into the partitioning technique and into perturbation theory In both cases, there exists a set of projection operators {Qk} which lead to a splitting of the Hilbert space into subspaces which have virtually nothing to do with each other It is shown that, in the partitioning technique, it is sufficient to consider one of these subspaces at a time, and the results are then generalized to perturbation theory It turns out that the finite-order expansions are no longer unique, and the commutation rules connecting the various forms are derived The infinite-order results are finally presented in such a form that they are later suitable for the evaluation of upper and lower bounds to the energy eigenvalues Le probleme de valeurs propres est formule dans une methode de la resolvante, basee sur une fonction de reference φ, et une variable complexe ℰ Ceci mene a un nombre de concepts fondamentaux tels que la fonction d'onde d'essai, l'equation inhomogene et les valeurs moyennes et “de transition” de l'Hamiltonien, d'ou l'on definit une “bracketing function” pour l'energie Pour eviter les procedes explicites pour tendre a la limite le probleme de valeurs propres est reformule dans le cadre de la methode de “partitioning”, ce qui mene a une “forme fermee” de la theorie des perturbations d'ordre infini Le problkme de valeurs propres est considerablement simplifie si 1′Hamiltonien H possede une constante du mouvement Λ ou des proprietes de symetrie caracterisees par le groupe G = {g} On pose alors le probleme d'incorporer ces simplifications dans la mkthode de “partitioning” et dans la theorie des perturbations Dans les deux cas il existe un ensemble de projecteurs {Qk}, qui entrainent une division de l'espace d'Hilbert en sous-espaces mutuellement exclusifs On demontre, que dans la methode de “partitioning”, il suffit de considerer un de ces sous-espaces a la fois, et les resultats sont ensuite, generalises a la theorie des perturbations II resulte que les developpements d'ordre fini ne sont pas uniques; on obtient des regles de commutation qui relient les formes differentes Les resultats d'ordre infini sont mis dans une forme qui est propre pour le calcul de bornes inferieures et superieures des valeurs propres de l'energie Das Eigenwertproblem wurde in der Sprache einer Resolventenmethode formuliert, die auf einer Referenzfunktion φ, und einem komplexen Veranderlichen ℰ basiert ist Dieses fuhrt zu einer Reihe von fundamentalen Begriffen wie die Vergleichswellenfunktion, die inhomogene Gleichung und die Mittel- und “Ubergangs”-werte des Hamiltonoperators, welche zu einer “bracketing function” fur die Energie fuhren Urn explizite Grenzuber-gange zu vermeiden, wurde dann das Eigenwertproblem in der Sprache der “partitioning”-Methode formuliert, was zu einer geschlossenen Form fur die Storungstheorie unendlicher Ordnung fuhrt Das Eigenwertproblem kann ansehnlich vereinfacht werden, wenn der Hamilton-operator eine Bewegungskonstante Λ oder Symmetrie-eigenschaften, die von der Gruppe G = {g} charakterisiert sind, hat Die Frage ist nun wie diese Vereinfachungen in der “Partitioning”-Methode und in der Storungstheorie aufgenommen werden konnen In beiden Fallen existiert ein Satz von Projektionsoperatoren { Qk}, welche zu einer Spaltung des Hilbertraumes in Unterraume fuhrt Es wurde gezeigt, dass es in der “Partitioning”-Methode hinreichend ist, einen dieser Unterraume zunachst zu betrachten; die Resultate wurden dann zur Storungstheorie verallgemeinert Es zeigt sich, dass die Entwicklungen endlicher Ordnung nicht einmalig sind; Kommutatorrelationen, die die verschiedene Formen verbinden, wurden hergeleitet Die Resultate unendlicher Ordnung wurden in einer Form gegeben, die fur die Berechnung oberer und unterer Grenzen der Energie-eigenwerte geeignet sind

Vocal Fry as a Phonational Register

Abstract: The purpose of this research was to test the hypothesis that vocal fry is a separate phonational register: specifically, whether or not the range of fundamental frequencies associated with vocal fr...

Self-Disclosure and Touching: A Study of Two Modes of Interpersonal Encounter and Their Inter-Relation

Abstract: IF contemporary Western man lives alienated from his fellows, his body,and nature, it behooves psychologists to investigate alienation in any of its manifestations, including its opposite -encounter. To encounter another person means, among other things, to confirm him as a being who experiences. This means seeking to experience his experience. I can experience your experience most directly if you disclose it to me. You can, if you wish, conceal or misrepresent your self, in which case my experience of you will be autistic. I will then believe things about your being that you know are untrue. But if you wish me to know you as you know yourself, you will have disclosed your experiencing authentically to me, in dialogue, throughout the duration of our relationship. A more direct, even literal, way for us to encounter one another, is for us to touch -my hand on some part of your body, and yours on mine. In touching you, I perceive you \"haptically,\" as Gibson puts it (1966, pp. 132-133). I know that you exist in a way that hearing you or seeing you cannot confirm. I may not know much about you and your experiencing in touching you, but I surely know that you are, that you are there in the flesh, so to speak. Indeed, Professor John Macmurray (1957, pp. 107-126) has provided an astute analysis of the way in which we of the West, since Descartes' time, have come to use the visual field as a model for knowing, while neglecting the kind of knowing that comes from direct touching. Visual knowing is contact at a distance. You have to be near to touch, taste, or smell another person. It would probably be appropriate to change the old saw, \"Seeing is believing,\" into the more fundamental source of truth about existence: \"Touching is believing.\" Indeed, if it is true that modern man lives out of his body, in a state of relative \"unembodiment\" -as Laing (1960) insiststhen I can surely awaken your experience of your body by touching you. And if Being discloses itself to our consciousness via our several sensory channels, then I can inquire into the means by which you disclose your being to me. How do you let me perceive you? Via my eyes? Ears? My touch receptors? Truly, for you to let me know you by touching you, you have let me get \"closer\" to you than if you limit yourself to verbal disclosure. When you let me touch you, you are disclosing your embodied being to my consciousness, by means of my tactual sense.

A biuret method for determination of protein in normal urine

Abstract: A biuret method has been developed which provides quantitative measurements of protein in normal urine without interference from drugs or pigments. This method is intended for use in monitoring clinical trials of new drugs—to detect nephrotoxicity. Protein is precipitated from duplicate samples of urine by addition of cold ethanolic phosphotungstic acid. The protein precipitates are separated by centrifugation and washed with ethanol. Protein from one of the duplicate samples is dissolvel in biuret reagent. Protein from the second sample is dissolved in an alkaline tartrate reagent which is identical to the biuret reagent, excepting that copper sulfate has been omitted. After 20 min., the differential absorbance of the two samples is measured at 540 mµ. The limit of sensitivity for detection of protein in urine is 0.5 mg./100 ml. The coefficient of variation of replicate analyses of protein in normal urine is 4.2%. The recovery of protein added to urine averages 103 ± 3%. Analyses of urinary protein by the biuret procedure provide close correlation with measurements by an amido black staining method. Systematic search has failed to reveal interference from urinary pigments, compounds, or drugs which are normally or occasionally encountered in hospitalized patients. In 24-hr. collections of urine from 28 healthy adults, the protein concentrations averaged 6.2 mg./100 ml. (range 3.0-12.2), and the protein excretions averaged 77 mg./day (range 40-150).

Electronic Wave Functions for Atoms. I. Ground State of Be

Abstract: A strategy is proposed to determine atomic wave functions by the configuration-interaction method (CI). A large nonoptimized set of Slater-type orbitals (STO's) is contracted into an orthogonal set of smaller dimension whose elements are natural orbitals (NO's) of a CI wave function which includes the Hartree-Fock (HF) configuration and, out of all possible double excitations, only those such that the HF orbitals are also NO's. Conceptual and practical arguments which justify such a procedure are given. A nonrelativistic calculation of the ground state of Be is made with an STO basis used earlier by Watson, but including $s$, $p$, and $d$ orbitals only. The final 180-term CI expansion (1492 Slater determinants) gives an energy $E=\ensuremath{-}14.664193$ atomic units (a.u.) (Be), which is about 0.00221 a.u. higher than a nonrelativistic estimate for this state, and the pair energies $\ensuremath{\epsilon}(1s, 1s)=\ensuremath{-}0.040869$ a.u., $\ensuremath{\epsilon}(2s, 2s)=\ensuremath{-}0.045104$ a.u., and $\ensuremath{\epsilon}(1s, 2s)=\ensuremath{-}0.005240$ a.u., are in excellent agreement with those found by Kelly by means of a many-body perturbation calculation, and also by Byron and Joachain, who used a variation-perturabtion method. Quantitative comparisons with all previous work on Be are made. Single excitations occur with large eigenvector components, but they become vanishingly small when NO's of the final wave function are used as the basis. The eigenvector components of quadruply excited configurations are closely related to those arising from a separated-electron-pair wave function without the strong orthogonality condition. The $\mathrm{spd}$ energy limit is estimated to be ${E}_{\mathrm{spd}}=\ensuremath{-}14.66453$ a.u. From considerations not involving relativistic corrections, the "exact" nonrelativistic energy is estimated to be lower than $E=\ensuremath{-}14.66639$ a.u. by no more than 0.0003 a.u. The "exact" pair energies are estimated to be $\ensuremath{\epsilon}(1s, 1s)=\ensuremath{-}0.04261$ a.u., $\ensuremath{\epsilon}(2s, 2s)=\ensuremath{-}0.04550$ a.u., and $\ensuremath{\epsilon}(1s, 2s)=\ensuremath{-}0.00530$ a.u. Details on all aspects of the calculation are given. Further work on several states of the first-row atoms is in progress.

The relation between ionization yields, cross sections and loss functions

Abstract: Three energy dependent quantities examined for gases, describing relation between ionization yields, cross section and loss functions

Kinetics of Crystallization in Li2O‐SiO2 Glasses

Abstract: The kinetics of crystallization of Li2Si2O5 from glasses in the Li2O-SiO2 system were studied using quantitative X-ray diffraction. Analysis of the data using the Johnson-Mehl-Avrami equation showed that crystallization occurred through the nucleation and growth of rods. The spherulitic nature of the crystals was substantiated by petrographic examinations of the partially crystalline glass. Analysis of the temperature dependence of the crystallization rate using a modification of the Johnson-Mehl-Avrami equation showed that the activation energy for nucleation was a function of composition and thermal treatment.

The mechanism of mitochondrial extrusion from phenylhydrazine-induced reticulocytes in the circulating blood.

Abstract: The mechanism of mitochondrial extrusion from reticulocytes was studied in whole blood from dogs made anemic by treatment with phenylhydrazine hydrochloride. The initial stage of preparation for mitochondrial extrusion was attraction of vesicles to mitochondria. There was subsequent encirclement of the organelle and other bodies, such as ferritin, by coalesced vesicles forming double membrane-limited vacuoles. Large vacuoles were formed from the union of single vacuoles, and they were usually situated near the periphery of the cell. Fusion of the outer membrane of vacuoles with the plasmalemma of the reticulocyte provided a route for exposure and release of mitochondria and other material to an extracellular location. An extracellular mitochondrion, therefore, was confined by its original double membrane, and a third membrane was derived from the internal boundary of vacuoles.

Anaerobic Brain Function: Effects of Stagnant and Anoxic Anoxia on Persistence of Breathing in Reptiles

Abstract: Turtles tolerate anoxic anoxia about 14 times longer than stagnant anoxia. In snakes and crocodiles this difference is much less marked. Apparently, the remarkable anaerobic viability of turtles is dependent on blood circulation, Analyses of plasma indicate that loss of brain function in anoxic crocodiles is not caused by systemic acidosis or hypoglycemia. It is suggested that the ability of the central nervous system of the turtle to function without oxygen is due to a comparatively high rate of anaerobic uptake or metabolism of glucose.

The Nilgiri langur (Presbytis johnii) mother-infant dyad

Abstract: There is considerable inter-generic and inter-specific variation in the mode and quality of the mother-infant relationship. Although the Nilgiri langur mother-infant dyad resembles that reported for most colobids, there are important differences. The Nilgiri and south Indian langur mother-infant pattern resemble each other more than each resembles the north Indian pattern. The Nilgiri langur mother-infant relationship differs from the north Indian pattern (especially) in the relative disinterestedness the Nilgiri langur mother exhibits for her infant, the earlier onset of weaning, the limited period of infant transferring, and the limited amount of mother-infant social interaction.

On nonlinear kinematic hardening

Abstract: Traditionally, the kinematic hardening assumption is used in conjunction with an assumption that the stress-strain curve for simple tension can be approximated by a bilinear curve. This paper generalizes the concept of kinematic hardening for the case when the stress-strain law is nonlinear. It is shown that although a yield condition of the form with κ constant or variable cannot represent non-linear kinematic hardening, at least one yield condition of the form where , represents such hardening.