176 results about "Electronic effect" patented technology

Devices and methods for detecting the constituent parts of biological polymers are disclosed. A molecular analysis device comprises a molecule sensor and a molecule guide. The molecule sensor comprises a single electron transistor including a first terminal, a second terminal, and a nanogap or at least one quantum dot positioned between the first terminal and the second terminal. A nitrogenous material disposed on the at least one quantum dot is configured for an interaction with an identifiable configuration of a molecule. The molecule sensor develops an electronic effect responsive to the interaction. The molecule guide is configured for guiding at least a portion of the molecule substantially near the molecule sensor to enable the interaction.

The invention relates to novel carbene ligands and their incorporated monomeric and resin / polymer linked ruthenium catalysts, which are recyclable and highly active for olefin metathesis reactions. It is disclosed that significant electronic effect of different substituted 2-alkoxybenzylidene ligands on the catalytic activity and stability of corresponding carbene ruthenium complexes, some of novel ruthenium complexes in the invention can be broadly used as catalysts highly efficient for olefin metathesis reactions, particularly in ring-closing (RCM), ring-opening (ROM), ring-opening metathesis polymerization (ROMP) and cross metathesis (CM) in high yield. The invention also relates to preparation of new ruthenium complexes and the use in metathesis.

Provided are a metallocene complex, a preparation method therefor, and a catalyst composition. The catalyst composition comprises a metallocene complex as represented by formula (I) and an organic boron salt. In contrast to the prior art, the metallocene complex as represented by the catalyst formula (I) used in the present invention contains no side chain, and has a large open degree of coordination space of the central metal, therefore having a higher catalytic activity and a higher insertion rate for strongly sterically hindered monomers. Moreover, the metallocene complex as represented by formula (I) used in the present invention is a fused heterocyclic cyclopentadienyl ligand, wherein the heterocycle has a strong capacity of supplying electrons, which can be used for fusing the cyclopentadienyl and changing the electronic effect in the metal centre so as to increase the activity of the catalyst. Hence, the metallocene complex as represented by formula (I) can be used for the preparation of a copolymer of ethylene and other alkenes with a high activity and a high insertion rate, and can also be used for catalyzing the polymerization of styrene and substituted styrene with high syndiotacticity and high activity.

A sensor for the detection of an analyte comprising a cis-diol moiety, which comprises a holographic element comprising a medium and a hologram disposed throughout the volume of the medium, wherein an optical characteristic of the element changes as a result of a variation of a physical property occurring throughout the volume of the medium, and wherein the medium is a polymer comprising a group of formula (I): wherein n is 0, 1, 2, 3 or 4; each X (if present) is independently is an atom or group which, via an electronic effect, promotes formation of a tetrahedral geometry about the boron atom; and Y is a spacer which, when n is 0 or otherwise optionally, is an atom or group which, via an electronic effect, promotes formation of a tetrahedral geometry about the boron atom. Such a sensor may be used for the detection of glucose.