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Papers by Patrick Riley

Research paper thumbnail of External biofidelity in lateral impact measurement of global and local forces

International Journal of Crashworthiness, 2011

A study was conducted to develop high-resolution external biofidelity data for the response of po... more A study was conducted to develop high-resolution external biofidelity data for the response of post-mortem human surrogates (PMHS) in side-impact loading. This study implemented stationary PMHS (N = 3) impacted by a wall moving at a constant velocity. The wall was subdivided into 15 impact plates, each instrumented to record the normal and shear forces as well as reaction moments

Research paper thumbnail of Formation of Tantalum “Tuck-in” Complexes by Activation of Methyl C−H Bonds in Pentamethylcyclopentadiene Groups by Carbazole Ligation

Organometallics, 1999

The reaction of [Cp*TaCl 4 ] with the potassium salt of carbazole (cbK, >3 equiv) in hydrocarbon ... more The reaction of [Cp*TaCl 4 ] with the potassium salt of carbazole (cbK, >3 equiv) in hydrocarbon solvents leads to the species [(C 5 Me 4 CH 2 )Ta(cb) 2 Cl] (1), in which one of the ring methyl C-H bonds of the Cp* ligand has been cleaved along with free cbH. Spectroscopic and structural studies of 1 show a lack of a plane of symmetry through the molecule with nonequivalent cb ligands. A minor component of the reaction mixture is believed to be the substitutional isomer 2, in which both carbazole ligands are equivalent. Alkylation of 1 with LiCH 2 SiMe 3 or PhCH 2 MgCl generates the corresponding monoalkyl derivatives [(C 5 Me 4 -CH 2 )Ta(cb) 2 (R)] (7 or 8, respectively). Structural studies of 1, 7, and 8 support an η 1 :η 5 -CH 2 C 5 Me 4 (σ:η 5 -CH 2 C 5 Me 4 ) description for the metalated ligands, with significant slippage toward an η 1 :η 3 -CH 2 C 5 Me 4 resonance form. To compare the extent of π-bonding between cb and dialkylamido ligands, the complex [(cb) 2 Ta(NMe 2 ) 3 ] (9) was synthesized and structurally characterized. The molecular structure of 9 consists of a tbp arrangement of nitrogen atoms with trans, axial cb ligands. The Ta-cb distances are 0.2 Å longer than the Ta-NMe 2 distances. An improved (safer) procedure for the synthesis of [Ta(NMe 2 ) 5 ] is presented.

Research paper thumbnail of Tyrosinase: The four oxidation states of the active site and their relevance to enzymatic activation, oxidation and inactivation

Bioorganic & Medicinal Chemistry, 2014

and sharing with colleagues.

Research paper thumbnail of The effect of age on the dynamics of a constrained chair rise

Journal of Biomechanics, 1993

Research paper thumbnail of NYLATRON WHITE NYLON WOOD CERAMIC SCREW CONVEYOR DRIVE WITH ACCESSORIES SPEED REDUCER SHAFT MOUNTED WITH ACCESSORIES. SADDLES AND FEET FLANGED COVER WITH ACCESSORIES

Research paper thumbnail of External biofidelity in lateral impact measurement of global and local forces

International Journal of Crashworthiness, 2011

A study was conducted to develop high-resolution external biofidelity data for the response of po... more A study was conducted to develop high-resolution external biofidelity data for the response of post-mortem human surrogates (PMHS) in side-impact loading. This study implemented stationary PMHS (N = 3) impacted by a wall moving at a constant velocity. The wall was subdivided into 15 impact plates, each instrumented to record the normal and shear forces as well as reaction moments

Research paper thumbnail of Formation of Tantalum “Tuck-in” Complexes by Activation of Methyl C−H Bonds in Pentamethylcyclopentadiene Groups by Carbazole Ligation

Organometallics, 1999

The reaction of [Cp*TaCl 4 ] with the potassium salt of carbazole (cbK, >3 equiv) in hydrocarbon ... more The reaction of [Cp*TaCl 4 ] with the potassium salt of carbazole (cbK, >3 equiv) in hydrocarbon solvents leads to the species [(C 5 Me 4 CH 2 )Ta(cb) 2 Cl] (1), in which one of the ring methyl C-H bonds of the Cp* ligand has been cleaved along with free cbH. Spectroscopic and structural studies of 1 show a lack of a plane of symmetry through the molecule with nonequivalent cb ligands. A minor component of the reaction mixture is believed to be the substitutional isomer 2, in which both carbazole ligands are equivalent. Alkylation of 1 with LiCH 2 SiMe 3 or PhCH 2 MgCl generates the corresponding monoalkyl derivatives [(C 5 Me 4 -CH 2 )Ta(cb) 2 (R)] (7 or 8, respectively). Structural studies of 1, 7, and 8 support an η 1 :η 5 -CH 2 C 5 Me 4 (σ:η 5 -CH 2 C 5 Me 4 ) description for the metalated ligands, with significant slippage toward an η 1 :η 3 -CH 2 C 5 Me 4 resonance form. To compare the extent of π-bonding between cb and dialkylamido ligands, the complex [(cb) 2 Ta(NMe 2 ) 3 ] (9) was synthesized and structurally characterized. The molecular structure of 9 consists of a tbp arrangement of nitrogen atoms with trans, axial cb ligands. The Ta-cb distances are 0.2 Å longer than the Ta-NMe 2 distances. An improved (safer) procedure for the synthesis of [Ta(NMe 2 ) 5 ] is presented.

Research paper thumbnail of Tyrosinase: The four oxidation states of the active site and their relevance to enzymatic activation, oxidation and inactivation

Bioorganic & Medicinal Chemistry, 2014

and sharing with colleagues.

Research paper thumbnail of The effect of age on the dynamics of a constrained chair rise

Journal of Biomechanics, 1993

Research paper thumbnail of NYLATRON WHITE NYLON WOOD CERAMIC SCREW CONVEYOR DRIVE WITH ACCESSORIES SPEED REDUCER SHAFT MOUNTED WITH ACCESSORIES. SADDLES AND FEET FLANGED COVER WITH ACCESSORIES

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