A halogen-containing compound as shown in a formula I can be used as a ligand for an ethylene oligomerization catalyst composition. The ethylene oligomerization catalyst composition containing the halogen-containing compound can be used to catalyze ethylene oligomerization, trimerization and tetramerization reactions. As a ligand of a catalyst for ethylene oligomerization, a fluoropolymer can effectively improve the catalytic performance of a catalyst system, and particularly exhibits improved activity and selectivity in an ethylene oligomerization reaction. ##STR00001##

The present invention relates to ligands based on calixarenes, metal complexes comprising such ligands and their use as homogeneous or heterogeneous catalysts.

The disclosure relates to chemical synthesis, and more particularly to a biphenyltetradentate phosphite compound and a preparation and application thereof. The compound has a structure of formula(I): ##STR00001##

A halogen-containing compound as shown in a formula I can be used as a ligand for an ethylene oligomerization catalyst composition. The ethylene oligomerization catalyst composition containing the halogen-containing compound can be used to catalyze ethylene oligomerization, trimerization, and tetramerization reactions. As a ligand of a catalyst for ethylene oligomerization, a fluoropolymer can effectively improve the catalytic performance of a catalyst system, and particularly exhibits improved activity and selectivity in an ethylene oligomerization reaction.

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The present disclosure relates to an organometallic framework modified using a compound having a hydroxyl group (—OH), a catalyst for a hydrogenation reaction including the same, and a method of manufacturing the same. The catalyst according to the present disclosure has high activity to the hydrogenation reaction even at a low temperature of 30 to 40° C., thus making low-grade waste heat usable.

The invention relates to a new dialkyl tin oxide catalyst composition and its use for the synthesis of amino alkyl (meth)acrylates by transesterification from an alkyl (meth)acrylates and an amino alcohol, and especially 2-dimethylaminoethyl (meth)acrylate.

The invention also relates to polymers made with quaternized amino alkyl (meth)acrylates and use of said polymers in water treatment, sludge dewatering, papermaking process, agriculture, cosmetic and detergency composition, textile process, oil and gas recovery process such as enhanced oil recovery, fracturing, mining operation such as tailings treatment.

A method of synthesizing a doped carbonaceous material includes mixing a carbon precursor material with at least one dopant to form a homogeneous/heterogeneous mixture; and subjecting the mixture to pyrolysis in an inert atmosphere to obtain the doped carbonaceous material. A method of purifying water includes providing an amount of the doped carbonaceous material in the water as a photocatalyst; and illuminating the water containing the doped carbonaceous material with visible light such that under visible light illumination, the doped carbonaceous material generates excitons (electron-hole pairs) and has high electron affinity, which react with oxygen and water adsorbed on its surface forming reactive oxygen species (ROS), such as hydroxyl radicals and superoxide radicals, singlet oxygen, hydrogen peroxide, that, in turn, decompose pollutants and micropollutants.

The disclosure relates to chemical synthesis, and more particularly to a biphenyltetradentate phosphite compound and a preparation and application thereof. The compound has a structure of formula(I):

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The invention includes procedures for stereoselective β-acylation of carboxylic acids having a β-carbon atom. For example, stereoselective acylation procedures include the following reactions: (I) ##STR00001##

A high-activity double-metal-cyanide catalyst, a method for fabricating the same, and applications of the same are disclosed. An organic complexing ligand, which is formed via mixing fatty alcohols and alicyclic carbonates, is used to generate a high-activity double-metal-cyanide catalyst. The high-activity double-metal-cyanide catalyst includes at least one double-metal-cyanide compound, at least one organic complexing ligand, and an optional functionalized compound. The double-metal-cyanide catalyst of the present invention has a higher activity than the conventional double-metal-cyanide catalysts. The polyols generated by the present invention has an insignificant amount of high-molecular-weight compounds.