Institution
ExxonMobil
Company•Irving, Texas, United States•
About: ExxonMobil is a company organization based out in Irving, Texas, United States. It is known for research contribution in the topics: Catalysis & Polymer. 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..
Topics: Catalysis, Polymer, Polymerization, Hydrocarbon, Alkyl
Papers published on a yearly basis
Papers
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TL;DR: In this article, a model system of wax and oil was used to understand the gelation process of these mixtures and a significant depression in the gel point of a wax-oil sample was observed by either decreasing the cooling rate or increasing the steady shear stress.
Abstract: High molecular weight paraffins are known to form gels of complex morphology at low temperatures due to the low solubility of these compounds in aromatic or naphthene-base oil solvents. The characteristics of these gels are strong functions of the shear and thermal histories of these samples. A model system of wax and oil was used to understand the gelation process of these mixtures. A significant depression in the gel point of a wax-oil sample was observed by either decreasing the cooling rate or increasing the steady shear stress. The wax-oil sample separates into two layers of different characteristics, a gel-like layer and a liquid-like layer, when sheared with a controlled-stress rheometer at high steady shear stresses and low cooling rates. The phase diagram of the model wax-oil system, obtained using a controlled-stress rheometer, was verified by analyzing the wax content of the incipient gel deposits formed on the wall of a flow loop. Based on the rheological measurements, a law has been suggested for the prediction of the wax content of the gel deposit on the laboratory flow loop walls. The wax content of the incipient gel formed on the wall of a field subsea pipeline was predicted to be much higher than that for the flow loop at similar operating conditions. This variation in the gel deposit characteristics is due to the significant differences in the cooling histories in the two cases.
175 citations
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23 Jul 1998TL;DR: Improved thermoplastic polymer blend compositions comprising an isotactic polypropylene component and an alpha-olefin and propylene copolymer component, comprising crystallizable alphaolefin sequences are provided in this article.
Abstract: Improved thermoplastic polymer blend compositions comprising an isotactic polypropylene component and an alpha-olefin and propylene copolymer component, said copolymer comprising crystallizable alpha-olefin sequences. In a preferred embodiment, improved thermoplastic polymer blends are provided comprising from about 35% to about 85% isotactic polypropylene and from about 30% to about 70% of an ethylene and propylene copolymer, wherein said copolymer comprises isotactically crystallizable propylene sequences and is predominately propylene. The resultant blends manifest unexpected compatibility characteristics, increased tensile strength, and improved process characteristics, e.g., a single melting point.
175 citations
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TL;DR: Experimental data demonstrate the dependence of this transition velocity on the intensity of the applied magnetic field, length of the bed, and type of magnetic solids, and the pressure distribution through the bed medium, the bedflow characteristics, and other phenomena.
Abstract: Fluidization of magnetizable particles by a gas stream in the presence of a uniform applied magnetic field oriented parallel to the flow prevents the hydrodynamic instability that otherwise leads to bubbles and turbulent motion within the medium. The fluidized emulsion expands uniformly in response to gas flow speeds in excess of that at the incipient fluidization point, with transition from the quiescent stable state to bubbling occurring suddenly at a characteristic increased rate of flow. Experimental data demonstrate the dependence of this transition velocity on the intensity of the applied magnetic field, length of the bed, and type of magnetic solids. Data illustrate the pressure distribution through the bed medium, the bedflow characteristics, and other phenomena.
175 citations
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TL;DR: Petroleum geochemistry improves exploration efficiency by accounting for many of the variables that control the volumes of crude oil and natural gas available for entrapment, including source-rock distribution, richness and quality, thermal maturity, and the timing of generation-migration-accumulation relative to trap formation as discussed by the authors.
174 citations
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TL;DR: The formation kinetics and self-assembly of multilamellar tubules of the diacetylenic phospholipid 1,2-bis(tricosa-10,12-diynoyl)-sn-glycerol-3-phosphocholine formed under controlled cooling rates are studied to form a highly efficient method of tubule production.
Abstract: The formation kinetics and self-assembly of multilamellar tubules of the diacetylenic phospholipid 1,2-bis(tricosa-10,12-diynoyl)-sn-glycerol-3-phosphocholine formed under controlled cooling rates were studied by x-ray diffraction and optical, atomic force, and scanning electron microscopy. Tubule formation was driven by a reversible first-order phase transition from an intralamellar, chain-melted L(alpha) phase to a chain-frozen L(beta), phase. These observations are the basis of a highly efficient method of tubule production in which tubule lengths can be controlled, between 1 and 100 micrometers, by varying the cooling rate. These tubules can be made in suspensions with 10 percent lipid by mass, far exceeding the lipid solubility limit.
174 citations
Authors
Showing all 16987 results
Name | H-index | Papers | Citations |
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David A. Weitz | 178 | 1038 | 114182 |
Avelino Corma | 134 | 1049 | 89095 |
Peter Hall | 132 | 1640 | 85019 |
James A. Dumesic | 118 | 615 | 58935 |
Robert H. Crabtree | 113 | 678 | 48634 |
Costas M. Soukoulis | 108 | 644 | 50208 |
Nicholas J. Turro | 104 | 1131 | 53827 |
Edwin L. Thomas | 104 | 606 | 40819 |
Israel E. Wachs | 103 | 427 | 32029 |
Andrew I. Cooper | 99 | 389 | 34700 |
Michael J. Zaworotko | 97 | 519 | 44441 |
Enrique Iglesia | 96 | 416 | 31934 |
Yves J. Chabal | 94 | 519 | 33820 |
George E. Gehrels | 92 | 454 | 30560 |
Ping Sheng | 90 | 593 | 37141 |