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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09 Apr 1996TL;DR: In this paper, an integrated, continuous process for the removal of organically bound sulfur (e.g., mercaptans, sulfides and thiophenes) comprising the steps of contacting a heavy oil, sodium hydroxide, hydrogen and water at a temperature of from about 380°C to 450°C, under a hydrogen pressure of at least about 50 psi to essentially desulfurize the oil, and form sodium sulfide.
Abstract: The invention relates to an integrated, continuous process for the removal of organically bound sulfur (e.g., mercaptans, sulfides and thiophenes) comprising the steps of contacting a heavy oil, sodium hydroxide, hydrogen and water at a temperature of from about 380°C to 450°C to partially desulfurize the heavy oil and to form sodium sulfide, contacting said sodium sulfide with a transition metal in water to form a transition metal sulfide, sodium hydroxide and hydrogen. The sodium hydroxide is recirculated and the transition metal sulfide is removed. The partially desulfurized, dewatered heavy oil is treated with sodium metal under desulfurizing conditions, typically at a temperature of from about 340°C to about 450°C, under a hydrogen pressure of at least about 50 psi to essentially desulfurize the oil, and form sodium sulfide. Optionally, the sodium salt generated can be regenerated to sodium metal using regeneration technology. The process advantageously produces essentially sulfur-free product oils having reduced nitrogen, oxygen and metals contents and reduced viscosity, density, molecular weight and heavy ends.
243 citations
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TL;DR: Porosity, permeability, and total organic carbon (TOC) in a heterogeneous suite of 21 high-maturity samples (vitrinite reflectance 1.52-2.15%) from the Barnett Shale in the eastern Fort Worth Basin display few correlations with parameters of rock texture, fabric, and composition, these factors being mostly obscured by the effects of a protracted history of diagenesis.
Abstract: Porosity, permeability, and total organic carbon (TOC) in a heterogeneous suite of 21 high-maturity samples (vitrinite reflectance 1.52–2.15%) from the Barnett Shale in the eastern Fort Worth Basin display few correlations with parameters of rock texture, fabric, and composition, these factors being mostly obscured by the effects of a protracted history of diagenesis. Diagenesis in these rocks includes mechanical and chemical modifications that occurred across a wide range of burial conditions. Compaction and cementation have mostly destroyed primary intergranular porosity. The porosity (average 5 vol. % by Gas Research Institute helium porosimetry) and pore size (8 nm median pore-throat diameter) are reduced to a degree such that pores are difficult to detect even by imaging Ar ion–milled surfaces with a field-emission scanning electron microscope. The existing porosity that can be imaged is mostly secondary and is localized dominantly within organic particulate debris and solid bitumen. The grain assemblage is highly modified by replacement. A weak pattern of correlation survives between bulk rock properties and the ratio of extrabasinal to intrabasinal sources of siliciclastic debris. Higher porosity, permeability, and TOC are observed in samples representing the extreme end members of mixing between extrabasinal siliciclastic sediment and intrabasinal-derived biosiliceous debris. Reservoir quality in these rocks is neither more strongly nor more simply related to variations in primary texture and composition because the interrelationships between texture and composition are complex and, importantly, the diagenetic overprint is too strong.
242 citations
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TL;DR: In this paper, the temperature dependence of conductivity for high-resistivity granular disordered systems in terms of the critical-path method was studied and compared with experiments and with other theoretical approaches.
Abstract: We study the temperature dependence of conductivity for high-resistivity granular disordered systems in terms of the critical-path method. It is shown that the low-field conductivity $\mathrm{exp}(\ensuremath{-}\frac{A}{{T}^{\ensuremath{\alpha}}})$ with $\ensuremath{\alpha}=\frac{1}{2}$ is obeyed over large temperature ranges with possible crossovers to $\ensuremath{\alpha}=\frac{1}{4}$ at low temperatures and to $\ensuremath{\alpha}g\frac{1}{2}$ at high temperatures. The temperatures at which the crossovers occur depend on the distribution of grain sizes. Comparisons are made with experiments and with other theoretical approaches.
242 citations
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TL;DR: In this paper, the authors studied the yield strength of paraffin-oil gels formed under various shear and thermal histories and found that the gel was formed under quiescent (shut-in) conditions, and the yield stress decreased with an increasing cooling rate.
241 citations
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01 Apr 1988-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, a new detection system based on an array of intrinsic Ge detectors is presented, which uses 13 individual 11 mm diameter Ge detectors, clustered in a 1:3:5:3):3:1 pattern on a common cryostat, combined with Soller slits and filters to reduce the background signals.
Abstract: At low concentrations, recording X-ray absorption spectra in fluorescence excitation mode is more sensitive than transmission mode. For dilute samples, the fluorescence signal is often obscured by scattered X-rays, and matrix and filter fluorescence. To discriminate against this background, while maintaining a large angular acceptance and high count rate capability, we have constructed a new detection system based on an array of intrinsic Ge detectors. The device uses 13 individual 11 mm diameter Ge detectors, clustered in a 1:3:5:3:1 pattern on a common cryostat, combined with Soller slits and filters to reduce the background signals. Pulsed optical feedback preamplifiers are followed by Gaussian-shaping amplifiers having fast discriminators to register the incoming count rate (ICR). Correction for dead time using the ICR signal allowed operation in the vicinity of 75 kHz per channel, with a 1 μs shaping time at 6 keV. For lower count rate applications, an average resolution of 160 eV at 5.9 keV was obtained with 8 μs shaping. Recent experience with this detector at the Stanford Synchrotron Radiation Laboratory is presented. The performance is illustrated using spectra obtained from phosphorus compounds and a thin iridium foil. The performance of this device is compared with previous fluorescence detection schemes, such as those using filter/slit combinations or barrel monochromators.
241 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 |