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Institution

ExxonMobil

CompanyIrving, 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
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Patent
30 Jul 1991
TL;DR: Ionic catalyst compositions can be prepared by combining two components as discussed by the authors : a bis(cyclopentadienyl) Group IV-B metal complex containing at least one ligand which will combine irreversibly with the second component or at least a portion thereof such as a cation portion thereof.
Abstract: Ionic catalyst compositions can be prepared by combining two components. The first component is a bis(cyclopentadienyl) Group IV-B metal complex containing at least one ligand which will combine irreversibly with the second component or at least a portion thereof such as a cation portion thereof. The second component comprises a cation which will irreversibly react with at least one ligand on the Group IV-B metal complex and a non-coordinating anion. The combination of the two components produces an ionic catalyst composition comprising a cationic bis(cyclopentadienyl) Group IV-B metal complex which has a formal coordination number of 3 and a 4+ valence charge and the aforementioned non-coordinating anion. The anion is (i) labile and can be displaced by an olefin, diolefin or acetylenically unsaturated monomer; (ii) has a molecular diameter about or greater than 4 angstroms; (iii) forms stable salts with reducible Lewis acids and protonated Lewis bases; (v) has a negative charge delocalized over the framework on the anion or within the core thereof; (v) is not a reducing or oxidizing agent; and (vi) is a relatively poor nucleophile. These ionic catalyst compositions can be used to polymerize α-olefins, diolefins and/or acetylenically unsaturated monomers, either alone or in combination, to polymers and copolymers.

670 citations

Journal ArticleDOI
28 Jul 1995-Science
TL;DR: In this model, the fluctuations in the force distribution arise because of variations in the contact angles and the constraints imposed by the force balance on each bead in the pile.
Abstract: Experimental observations and numerical simulations of the large force inhomogeneities present in stationary bead packs are presented. Forces much larger than the mean occurred but were exponentially rare. An exactly soluble model reproduced many aspects of the experiments and simulations. In this model, the fluctuations in the force distribution arise because of variations in the contact angles and the constraints imposed by the force balance on each bead in the pile.

661 citations

Journal ArticleDOI
TL;DR: Eight companies that were Process Effectiveness Network members of the Industrial Research Institute attempted to collectively determine the best practices of the Fuzzy Front End (FFE) of innovation developed a theoretical construct, defined as the New Concept Development (NCD) model, in order to provide a common language and insights on the front end activities.
Abstract: OVERVIEW:Eight companies that were Process Effectiveness Network members of the Industrial Research Institute attempted to collectively determine the best practices of the Fuzzy Front End (FFE) of innovation. Comparing one company's processes to those of another proved insurmountable because there was neither a common language nor clear and consistent definition of the key elements of the front end. As a result, the group developed a theoretical construct, defined as the New Concept Development (NCD) model, in order to provide a common language and insights on the front end activities. The model consists of three key parts: five front end elements, the engine that powers the elements, and external influencing factors. Proficiency of the FFE was evaluated at 19 companies by using the NCD model. Highly innovative companies were found to be more proficient in the FFE and in several elements of the NCD model.

649 citations

Patent
19 Mar 1991
TL;DR: In this article, a method for using such system, for the enhanced production of homo and copolymer products of olefin, diolefin and/or acetylenically unsaturated monomers.
Abstract: This invention relates to catalyst systems, and a method for using such system, for the enhanced production of homo and copolymer products of olefin, diolefin and/or acetylenically unsaturated monomers. This invention catalyst system comprises a Group III-A element compound for improving the productivity of an olefin polymerization catalyst which is the reaction product of a metallocene of a Group IV-B transition metal and an ionic activator compound comprising a cation capable of donating a proton and an anion which is bulky, labile and noncoordinateable with the Group IV transition metal cation produced upon reaction of the metallocene and activator compound to form the catalyst component of the catalyst system.

648 citations

Patent
27 Feb 2002
TL;DR: In this article, the authors present a system, methods, and non-transitory computer-readable storage media for receiving data from a giver at a first time, the data being used to identify a merchant at which a gift from the giver to a recipient is redeemable.
Abstract: Disclosed herein are systems, methods, and non-transitory computer-readable storage media for receiving data from a giver at a first time, the data being used to identify a merchant at which a gift from the giver to a recipient is redeemable. The system presents a group of merchants associated with the data to the giver, each merchant of the group of merchants offering a promotion in connection with the gift. The system receives from the giver a selection of a chosen merchant from the group of merchants, the chosen merchant having an associated promotion. The system then generates a policy comprising the gift, the chosen merchant, and the associated promotion such that upon receiving an indication of a triggering event caused by the recipient, the system can apply the gift and the associated promotion according to the policy.

647 citations


Authors

Showing all 16987 results

NameH-indexPapersCitations
David A. Weitz1781038114182
Avelino Corma134104989095
Peter Hall132164085019
James A. Dumesic11861558935
Robert H. Crabtree11367848634
Costas M. Soukoulis10864450208
Nicholas J. Turro104113153827
Edwin L. Thomas10460640819
Israel E. Wachs10342732029
Andrew I. Cooper9938934700
Michael J. Zaworotko9751944441
Enrique Iglesia9641631934
Yves J. Chabal9451933820
George E. Gehrels9245430560
Ping Sheng9059337141
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20234
202236
2021302
2020340
2019366
2018438