Technology Trends of Catalysts in Hydrogenation Reactions: A Patent Landscape Analysis.

The purpose of this review is to present an overview of the patent landscape for catalysts used in hydrogenation reactions. Based on patent data extracted from PatBase®, we use predefined patent classifications as well as a keyword-based search for our analyses. The results indicate that the number of patent families that protect heterogeneous catalysts grows twice as fast as that for their homogeneous counterparts.

Direct estimate of the internal π-donation to the carbene centre within N-heterocyclic carbenes and related molecules.

Fifteen cyclic and acylic carbenes have been calculated with density functional theory at the BP86/def2-TZVPP level. The strength of the internal X→p(π) π-donation of heteroatoms and carbon which are bonded to the C(II) atom is estimated with the help of NBO calculations and with an energy decomposition analysis. The investigated molecules include N-heterocyclic carbenes (NHCs), the cyclic alkyl(amino)carbene (cAAC), mesoionic carbenes and ylide-stabilized carbenes.

Dental health knowledge, attitudes and behaviour among students at the Kuwait University Health Sciences Centre.

Objective: The aim of the study was to determine the extent of dental health knowledge among students at the Kuwait University Health Sciences Centre (HSC), as well as their attitudes toward dental health and their oral hygiene habits.

Methods: A structured questionnaire was distributed to 450 of the 800 students enrolled in 3 faculties of the HSC from March to April 2000. The questionnaire was completed anonymously by the students.