ExxonMobil

About: ExxonMobil is a company organization based out in Irving, Texas, United States. It is known for research contribution in the topics: Catalysis & Polymerization. The organization has 16969 authors who have published 23758 publications receiving 535713 citations. The organization is also known as: Exxon Mobil Corporation & Exxon Mobil Corp..

High‐temperature mutual solubilities of hydrocarbons and water. Part II: Ethylbenzene, ethylcyclohexane, and n‐octane

Abstract: In Part I (Tsonopoulos and Wilson, 1983), the mutual solubilities of three C6 hydrocarbons (benzene, cyclohexane, n-hexane) and water were experimentally investigated and, together with critically selected literature data, were correlated up to the three-phase critical end point. The present paper extends this analysis to the mutual solubilities of three C8 hydrocarbons (ethylbenzene, ethylcyclohexane, n-octane) and water, which have been measured at the three-phase equilibrium pressure up to the critical temperatures (568, 561 and 539 K, respectively). A thermodynamic analysis of these new measurements and of available literature data has been performed up to the three-phase critical end point. Information is also provided on vapor-phase equilibrium compositions. The solubility of hydrocarbons in water has been used to calculate Henry's constants, while the solubility and volatility of water in hydrocarbons has been successfully correlated with several modifications of the Redlich-Kwong equation of state.

Point-of-sale system using multi-threaded transactions and interleaved file transfer

Abstract: A dial-up asynchronous communication protocol allowing multiple POS terminals to efficiently multi-thread transactions to a host computer and to interleave mail messages and file transfers while retaining the ability to suspend these mail messages and file transfers when credit card authorization requests from the terminal or responses to those authorization requests from the host become available, and resume the mail messages and file transfers after the requests or responses have been transmitted.

Normal and Shear Forces Between Polymer Brushes

Abstract: Surface-polymer interactions are important in many technological applications, including colloidal stablization and adherence. Recently there has been considerable progress in understanding these interactions and the resulting forces between polymer-bearing surfaces. End-grafted polymers, commonly referred to as polymer brushes, are one example of a polymer-surface complex which has many interesting properties. In this article, recent progress in understanding the normal and shear forces between polymer brushes is reviewed with emphasis on the contributions from molecular simulations. These simulations show that under steady-state shear flow, some of the individual chains of a polymer brush stretch in the direction of flow while most are buried inside of the brush and are not affected by the shear flow. The height of the brush is only weakly dependent on the shear rate in contrast with several theoretical models. When two surfaces bearing end-grafted chains are brought into contact the normal force increases rapidly with decreasing plate separation, while the shear force is in most cases significantly smaller, particularly for large compressions. However, for weak compression, the range and the magnitude of the shear force depends on both the solvent quality and shear rate. These results, first observed experimentally using the surface force apparatus and recently confirmed in simulation, suggest a way to dramatically reduce the frictional force between two surfaces. For small relative velocity of the two surfaces, the surfaces slide pass each other with almost no change in the average radius of gyration of the chains or the amount of interpenetration of chains from the two surfaces. However, for large shear rates, there is significant stretching and some disentanglement of the chains.

The structure of fractal colloidal aggregates of finite extent

Abstract: The structure of fractal colloid aggregates formed in both the diffusion- and the reaction-limited regimes is studied by static light scattering experiments. The crossover region of the structure factor of the clusters is measured, and the effects of the finite extent of the fractal structure on the scattering are investigated. The polydispersity of the cluster mass distribution markedly changes the shape of the measured scattering intensity. A form for the structure factor obtained from computer-generated clusters is found to describe the colloidal aggregates very well, for both regimes. Other available models for the crossover region are also discussed. In addition, the effects of the optical plasma resonance in the case of metallic colloids and the effects of cluster restructuring on the static scattering are discussed.

Lithium‐Aluminum Electrode

Abstract: Lithium--aluminum anodes were investigated as a possible approach to minimizing the lithium dendrite problem in organic electrolyte secondary cells. Electroformation and pyrometallurgical techniques were used in the preparation of the electrodes. The equilibrium emf--composition relationship and the cycling behavior were evaluated. Under certain conditions Li--Al compositions approaching lithium potentials may be used; the voltage penalty required to minimize the dendrite problem is reduced in this way. 3 figures, 2 tables.