Studies in the physical chemistry of detonation and related topics

The well-established physical theory of detonation specifies the properties of the infinite plane detonation wave in terms of the thermochemistry of the detonation reaction and the equation of state of the detonation products, (see, for example, Taylor, 1952). Thus physical chemistry has two roles in the discussion of the plane detonation wave, the provision of thermochemical information and the determination of the equation of state. This theory deals however with an ideal case, in which rate processes have no effect; in the real wave, complicated rate processes have to be taken into account. Here again physical chemistry has information to supply in the fields of chemical kinetics and rates of energy transfer. The present thesis deals with contributions to physical chemistry in the fields of thermochemistry, equation of state and intermolecular forces, chemical kinetics and energy transfer.LIST OF PAPERS: (1) The preparation and heats of combustion of some amine nitrates T. L. Cottrell and J. E. Gill, J. Chem. Soc., 1951, 1798. || (2) Binding energies in hydrocarbons || (3) Resonance energies from thermal data T. L. Cottrell and L. E. Sutton, J. Chem. Physics, 1947, 15, 685 (Letter) || (4) Covalency, electrovalency and electronegativity, T. L. Cottrell and L. E. Sutton, Proc. Roy. Soc. A, 1951, 207, 49 || (5)The interpretation of bond properties, T. L. Cottrell and L. E. Sutton, Quart. Rev. Chem. Soc., 1948, 2, 260 || (6) The strengths of chemical bonds T. L. Cottrell, Butterworths, London, 1954, 310 + viii pp. (Book) || (7) Repulsive intermolecular forces, T. L. Cottrell, Discussion of the Faraday Society, 1956, 22, 10 || (8) Electronic kinetic energy in gases at high pressures, T. L. Cottrell, J. Chem. Physics , 1950, 18, 1117 (Letter) || (9) Molecular energy at high pressure, T. L. Cottrell, Trans. Faraday Soc., 1951, 47, 337 || (10) The virial theorem in quantum mechanics, T. L. Cottrell and S. Paterson, Phil. Mag. 1951, (7), t,2, 391 || (11) Approximate wave -functions satisfying the virial theorem, T. L. Cottrell and S. Paterson, Trans. Faraday Soc., 1951, 47, 233 || (12) An equation of state applicable to gases at densities near that of the solid and temperatures far above the critical, T. L. Cottrell and S. Paterson, Proc. Roy. Soc. A, 1952, 213, 214 || (13) The second virial coefficient of gases and mixtures. Part 1 - Carbon dioxide + helium mixtures T. L. Cottrell and R. A. Hamilton, Trans. Faraday Soc., 1956, 52, 156 || (14) The second virial coefficient of gases and mixtures. Part 2 - Mixtures of carbon dioxide with nitrogen, oxîgen,carbon monoxide, argon and hydrogen T. L. Cottrell, R. A Hamilton and R. P. Taubinger, Trans. Faraday 8( 4., 1956, 52, 1310 || (15) The thermal decomposition of nitromethane, T. L. Cottrell, T. E. Graham and T. J. Reid, Trans. Faraday Soc., 1951, 47, 584. || (16) The thermal decomposition of nitroethane and 1- nitropropane T. L. Cottrell, T. E. Graham and T. J. Reid, Trans. Faraday Soc., 1951, 47, 1089 || (17) The kinetics of the oxidation of ethylene by nitrogen dioxide T. L. Cottrell and T. 8. Graham, J. Chem. Soc., 1953, 556 || (18) The kinetics of the oxidation of propylene by nitrogen dioxide T. L. Cottrell and T.: S. Graham, J. Chem. Soc., 1954, 3644 (Note) || (19) Importance of gas spaces in the propagation of detonation of granular explosives T. L. Cottrell, J. G. Gibb, Nature, 1956, 178, 814 || (20) Transition probability in molecular encounters. Part 1 - The evaluation of perturbation integrals T. L. Cottrell and N. Ream, Trans. Faraday Soc., 1955, 51, 159 || (21) Transition probability in molecular encounters. Part 2 - Vibrational relaxation time in methane, T. L. Cottrell and N. Ream, Trans. Faraday Soc., 1955, 51, 1153 || (22) Transition probability in molecular encounters. Part 3 - Experimental values for relaxation time in methane T. L. Cottrell and (Mss) P. F. 'Martin, Trans. Faraday Soc., 1957, 53, 11s

Interview with Zeleme (Brashear) Cottrell (FA 15)

Transcription of interview with Estella Zeleme (Brashear) Cottrell conducted by Ann Celine Taft on 23 September 1983. From a project with Zeleme Cottrell discussing her weaving, the weaving process in depth, and how it has affected her life

Probabilistic political economy and endogenous money

Since the foundational work of Farjoun and Machover , important contributions to the field of probabilistic economy have been made. In this context one naturally has conservation of money as a postulate. However it is questionable whether a capitalist economy could ever work with entirely exogenous money, and it is interesting to see to what extent probabilistic arguments can illuminate the evolution of the type of endogenous money system that characterizes contemporary capitalism. We first argue, on probabilistic grounds, that a system with a strict conservation law on money was historically unsustainable. We then make the case that phenomena such as the formation of a rate of interest, periodic commercial crises, and the formation of a rentier class can be understood using the sort of reasoning pioneered by Farjoun and Machove

Is economic planning hypercomputational? The argument from Cantor diagonalisation

Murphy [26] argues that the diagonal argument of the number theorist Cantor can be used to elucidate issues that arose in the socialist calculation debate of the 1930s. In particular he contends that the diagonal argument buttresses the claims of the Austrian economists regarding the impossibility of rational planning.We challenge Murphy’s argument, both at the number theoretic level and from the standpoint of economic realism

Social Facilitation: Differential Recall of Paired-Associates as a Function of Socially Induced Arousal, Repetition, and Retention Interval

Predictions based on Cottrell\u27s learned drive extension of Zajonc\u27s hypothesis of social facilitation were investigated in a 2 x 2 x 2 factorial design. Sixty-four male subjects were shown a paired-associate list once or three times and then tested for recall either 2 min. or 45 min. later. Arousal at the time of learning was manipulated by the experimenter either closely observing or not observing subjects. After one learning trial, precisely the same form of Arousal X Retention Interval interaction found by Geen (1973) was obtained: observed subjects recalled fewer items at 2 min. than did unobserved subjects, while contrary to Cottrell\u27s hypothesis, this relationship reversed at 45 min. (ps\u3c.05). After three trials, no significant differences were found, although the means (higher for observed subjects tested at 2 min. and 45 min.) were in the direction predicted by Cottrell\u27s hypothesis

Mesoscopic Analysis of Structure and Strength of Dislocation Junctions in FCC Metals

We develop a finite element based dislocation dynamics model to simulate the structure and strength of dislocation junctions in FCC crystals. The model is based on anisotropic elasticity theory supplemented by the explicit inclusion of the separation of perfect dislocations into partial dislocations bounding a stacking fault. We demonstrate that the model reproduces in precise detail the structure of the Lomer-Cottrell lock already obtained from atomistic simulations. In light of this success, we also examine the strength of junctions culminating in a stress-strength diagram which is the locus of points in stress space corresponding to dissolution of the junction.Comment: 9 Pages + 4 Figure

Translation efficiency is a determinant of the magnitude of miRNA-mediated repression

Abstract MicroRNAs are well known regulators of mRNA stability and translation. However, the magnitude of both translational repression and mRNA decay induced by miRNA binding varies greatly between miRNA targets. This can be the result of cis and trans factors that affect miRNA binding or action. We set out to address this issue by studying how various mRNA characteristics affect miRNA-mediated repression. Using a dual luciferase reporter system, we systematically analyzed the ability of selected mRNA elements to modulate miRNA-mediated repression. We found that changing the 3′UTR of a miRNA-targeted reporter modulates translational repression by affecting the translation efficiency. This 3′UTR dependent modulation can be further altered by changing the codon-optimality or 5′UTR of the luciferase reporter. We observed maximal repression with intermediate codon optimality and weak repression with very high or low codon optimality. Analysis of ribosome profiling and RNA-seq data for endogenous miRNA targets revealed translation efficiency as a key determinant of the magnitude of miRNA-mediated translational repression. Messages with high translation efficiency were more robustly repressed. Together our results reveal modulation of miRNA-mediated repression by characteristics and features of the 5′UTR, CDS and 3′UTR

Serration and Reversion Treatment in Al-10mass%Zn Alloy

The relationship between occurrence of serration and reversion heat treatment was studied by tensile test on Al-10mass%Zn alloy. Serration was observed for the furnace cooled specimen, but not for the as-quenched one and the shortly aged one, which result is difficult to be interpreted by the Cottrell theory. The stress amplitude in the serration increased with increasing the time of annealing for reversion up to 10ks and then stayed at a constant value which might be interpreted by the Cottrell theory. The stress amplitude in the serration decreased with increasing the annealing temperature, which is contrary to the prediction by the Cottrell theory. The specimen directly annealed without aging and the one annealed after aging agreed well with each other in the tensile strength and the stress amplitude in the serration, which suggests solute clusters as the cause of serration