26,942 research outputs found
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Department of Management EngineeringFirms participating in printer industries have invested their constrained resources into technology development in order to sustain their competitiveness in the industry. Considering the fast-changing market circumstances, each firm???s own investment decisions on technology portfolio may directly affect their performance.
In this study, we analyzed patent data, namely number of forward citations and technological classification data (CPC). Using this data, the technological portfolio of a specific firm can be identified, which can further help our understanding on firms??? R&D investment strategies. Number of studies mainly focused on patent class combinations of individual technology level, but portfolios of patent class at a firm level have been understudied.
In this study, we tracked the change of class composition within each firms??? technological patents??? portfolio and attempted to identify practical and theoretical implications to portfolio management. We utilized Entropy Index, Co-occurrence and cosine similarities measurements for each indicating diversification, patent scope and portfolio similarities within each patents??? classification subclasses. Additionally, performance evaluation of each portfolio is conducted using forward citation data.
This paper shows that in-depth patent data analysis can allow us to explore deeper insights at various levels, individual technology, products and product lines, and firms sufficing different stories.ope
Regioselective Intermolecular Coupling Reaction of Arylketones and Alkenes Involving C-H Bond Activation Catalyzed by an \u3cem\u3ein Situ\u3c/em\u3e Formed Cationic Ruthenium-Hydride Complex
The cationic ruthenium hydride complex, formed in situ from the treatment of the tetranuclear ruthenium hydride complex {[(PCy3)(CO)RuH]4(ÎŒ4-O)(ÎŒ3-OH)(ÎŒ2-OH)} with HBF4·OEt2, was found to be a highly effective catalyst for the intermolecular coupling reaction of arylketones and 1-alkenes to give the substituted indene and ortho-CâH insertion products. The formation of the indene products resulted from the initial alkene isomerization followed by regioselective ortho-CâH insertion of 2-alkene and dehydrative cyclization. The preliminary mechanistic studies revealed a rapid and reversible ortho-CâH bond activation followed by the rate-limiting CâC bond formation step for the coupling reaction
Efficient Dehydrogenation of Amines and Carbonyl Compounds Catalyzed by a Tetranuclear Ruthenium-Ό-oxo-Ό-hydroxo-hydride Complex
The tetranuclear ruthenium-ÎŒ-oxo-ÎŒ-hydroxo-hydride complex {[(PCy3)(CO)RuH]4(ÎŒ4-O)(ÎŒ3-OH)(ÎŒ2-OH)} (1) was found to be a highly effective catalyst for the transfer dehydrogenation of amines and carbonyl compounds. For example, the initial turnover rate of the dehydrogenation of 2-methylindoline was measured to be 1.9 sâ1 with a TON of 7950 after 1 h at 200 °C. The extensive H/D scrambling patterns observed from the dehydrogenation reaction of indoline-N-d1 and indoline-α-d2 suggest a monohydride mechanistic pathway with the CâH bond activation rate-limiting step
Chain-Selective and Regioselective Ethylene and Styrene Dimerization Reactions Catalyzed by a Well-Defined Cationic Ruthenium-Hydride Complex: New Insights on the Styrene Dimerization Mechanism
The cationic ruthenium hydride complex [(η6-C6H6)(PCy3)(CO)RuH]+BF4â was found to be a highly regioselective catalyst for the ethylene dimerization reaction to give 2-butene products (TOF = 1910 hâ1, \u3e95% selectivity for 2-butenes). The dimerization of styrene exclusively produced the head-to-tail dimer (E)-PhCH(CH3)CHâCHPh at an initial turnover rate of 2300 hâ1. A rapid and extensive H/D exchange between the vinyl hydrogens of styrene-d8 and 4-methoxystyrene was observed within 10 min without forming the dimer products at room temperature. The inverse deuterium isotope effect of kH/kD = 0.77 ± 0.10 was measured from the first-order plots on the dimerization reaction of styrene and styrene-d8 in chlorobenzene at 70 °C. The pronounced carbon isotope effect on both vinyl carbons of styrene as measured by using Singletonâs method (13C(recovered)/13C(virgin) at C1 = 1.096 and C2 = 1.042) indicates that the CâC bond formation is the rate-limiting step for the dimerization reaction. The Eyring plot of the dimerization of styrene in the temperature range of 50â90 °C led to ÎH⧧ = 3.3(6) kcal/mol and ÎS⧧ = â35.5(7) eu. An electrophilic addition mechanism has been proposed for the dimerization of styrene
Intermolecular Dehydrative Coupling Reaction of Arylketones with Cyclic Alkenes Catalyzed by a Well-Defined Cationic Ruthenium-Hydride Complex: A Novel Ketone Olefination Method via Vinyl CâH Bond Activation
The cationic rutheniumâhydride complex [(η6-C6H6)(PCy3)(CO)RuH]+BF4â was found to be a highly effective catalyst for the intermolecular olefination reaction of aryl ketones with cycloalkenes. The preliminary mechanistic analysis revealed that an electrophilic rutheniumâvinyl complex is the key species for mediating both vinyl CâH bond activation and the dehydrative olefination steps of the coupling reaction
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