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..

Multiple timescales for neutralization of fossil fuel CO2

Abstract: The long term abiological sinks for anthropogenic CO2 will be dissolution in the oceans and chemical neutralization by reaction with carbonates and basic igneous rocks. We use a detailed ocean/sediment carbon cycle model to simulate the response of the carbonate cycle in the ocean to a range of anthropogenic CO2 release scenarios. CaCO3 will play only a secondary role in buffering the CO2 concentration of the atmosphere because CaCO3 reaction uptake capacity and kinetics are limited by the dynamics of the ocean carbon cycle. Dissolution into ocean water sequesters 70–80% of the CO2 release on a time scale of several hundred years. Chemical neutralization of CO2 by reaction with CaCO3 on the sea floor accounts for another 9–15% decrease in the atmospheric concentration on a time scale of 5.5–6.8 kyr. Reaction with CaCO3 on land accounts for another 3–8%, with a time scale of 8.2 kyr. The final equilibrium with CaCO3 leaves 7.5–8% of the CO2 release remaining in the atmosphere. The carbonate chemistry of the oceans in contact with CaCO3 will act to buffer atmospheric CO2 at this higher concentration until the entire fossil fuel CO2 release is consumed by weathering of basic igneous rocks on a time scale of 200 kyr.

Effects of Polydispersity in the End-Grafted Polymer Brush

Abstract: We consider the effects of polydispersity in molecular weight on the equilibrium statistics of the grafted polymer brush. We use a self-consistent field method, exploiting the fact that the chains in the brush are strongly stretched, to map the problem onto one involving the trajectories of classical particles. A general solution for the density or pressure profile and the force required to compress a brush is given in terms of the distribution of molecular weights. The profile is a unique function of the molecular weight distribution and vice versa. Results are also given for a "brush" whose density profile is constrained to be uniform, as is appropriate to the description of lamellar mesophases of block copolymer melts. Consequences for force-balance experiments and for colloid stabilization are discussed.

Electrical devices comprising polymeric insulating or semiconducting members

Abstract: Disclosed are electrically conductive and semiconductive devices utilizing polymers having resistance to water treeing and good dielectric properties. The polymer comprises ethylene polymerized with at least one C 3 to C 20 alpha-olefin and optionally at least one C 3 to C 20 polyene. The polymer utilized has a density in the range of about 0.86 g/cm 3 to about 0.96 g/cm 3 , a melt index in the range of about 0.2 dg/min to about 100 dg/min, a molecular weight distribution in the range of about 1.5 to about 30, and a composition distribution breadth index greater than about 45 percent. For the polymer utilized, the tree rating is generally less than about 40, the power factor is in the range of about 0.0002 to about 0.0005, and the dielectric constant is in the range of about 1.8 to about 2.4.

Experimental models of extensional forced folds

Abstract: We have used single-layer and multilayer clay models to study the development of forced folds above normal faults. Our modeling results show that the deformation patterns associated with extensional forced folding depend on the dip of the underlying normal fault and the presence of layer-parallel detachments. In single-layer clay models, extensional forced folds are upward-widening monoclines. Anticlinal axial surfaces dip in the same direction as underlying master normal faults, and synclinal axial surfaces dip in the opposite direction of master normal faults. Most secondary faults are upward-steepening normal faults. If master normal faults are steeply dipping, however, many secondary normal faults become high-angle reverse faults at shallow depths. The propagation and linkage of secondary faults into through-going normal faults terminates the development of extensional forced folds. More folding occurs prior to fault linkage if the master normal fault is steeply dipping rather than gently dipping. Most dipping beds and secondary faults are preserved in the hanging walls of the through- oing normal faults. In multilayer clay models with layer-parallel detachments, extensional forced folds are also upward-widening monoclines. Slip on the lowest detachment laterally transfers extension induced by normal faulting and forced folding from the master normal fault to the detachment edge. Slip on overlying detachments accommodates minor thickness changes associated with upward-widening of the fold. Secondary faults include low-angle normal faults near the anticlinal axial surface, minor thrust faults near the synclinal axial surface, and high-angle normal faults above the detachment edge. The model-predicted deformation patterns are similar to those of extensional forced folds from the Gulf of Suez and offshore Norway. This similarity suggests that our modeling results apply to extensional forced folds and can provide guidelines for interpreting field, well, and seismic data.