Abstract: The present invention provides a preparation method of a catalyst component for olefin polymerization, comprising firstly dissolving an anhydrous magnesium halide into a mixed solvent which comprises an oxygen-containing organic titanium compound, an organic epoxy compound, a hydroxy-containing compound, and an inert solvent, and does not comprise a phosphate compound, so as to form a magnesium halide solution; then mixing the magnesium halide solution with a halogen-containing compound to precipitate a solid, so as to obtain the catalyst component, wherein the halogen-containing compound comprises at least one selected from a group consisting of halogen and titanium-containing compounds, halogenated organic hydrocarbon compounds, acyl halide compounds, halogen and phosphorus-containing compounds, halogen and boron-containing compounds, halogenated organic aluminum compounds, and halogen and silicon-containing compounds.

Abstract: A magnesium halide solution is disclosed. The magnesium halide solution comprises a magnesium halide, an oxygen-containing organic titanium compound, a hydroxyl-containing compound, and an organic solvent. The magnesium halide solution further comprises an organic heterocyclic compound. The organic solvent is a hydrocarbon and/or a halogenated hydrocarbon. The organic heterocyclic compound is at least one selected from a group consisting of a sulphur-containing organic heterocyclic compound, a nitrogen-containing organic heterocyclic compound, and an organic epoxy compound. The magnesium halide solution has a good stability, and can be used for preparing a catalyst for olefin polymerization and copolymerization reactions. The raw material of the magnesium halide solution is cheap and easy to be obtained. The preparing method is easy to be performed and is environment-friendly.

Abstract: A magnesium halide solution is disclosed. The magnesium halide solution comprises a magnesium halide, an oxygen-containing organic titanium compound, a hydroxyl-containing compound, and an organic solvent. The magnesium halide solution further comprises an organic heterocyclic compound. The organic solvent is a hydrocarbon and/or a halogenated hydrocarbon. The organic heterocyclic compound is at least one selected from a group consisting of a sulphur-containing organic heterocyclic compound, a nitrogen-containing organic heterocyclic compound, and an organic epoxy compound. The magnesium halide solution has a good stability, and can be used for preparing a catalyst for olefin polymerization and copolymerization reactions. The raw material of the magnesium halide solution is cheap and easy to be obtained. The preparing method is easy to be performed and is environment-friendly.

Abstract: The present invention provides a preparation method of a catalyst component for olefin polymerization, comprising firstly dissolving an anhydrous magnesium halide into a mixed solvent which comprises an oxygen-containing organic titanium compound, an organic epoxy compound, a hydroxy-containing compound, and an inert solvent, and does not comprise a phosphate compound, so as to form a magnesium halide solution; then mixing the magnesium halide solution with a halogen-containing compound to precipitate a solid, so as to obtain the catalyst component, wherein the halogen-containing compound comprises at least one selected from a group consisting of halogen and titanium-containing compounds, halogenated organic hydrocarbon compounds, acyl halide compounds, halogen and phosphorus-containing compounds, halogen and boron-containing compounds, halogenated organic aluminium compounds, and halogen and silicon-containing compounds.

Abstract: The present invention discloses a method for implementing a Push-To-Talk (PTT) service, including: establishing a connection between a terminal and a conference room in a conference system with half-duplex communication mode; receiving a request sent by the terminal and providing the PTT corresponding to the request according to a stored corresponding relation between the PTT services and the requests. According to the method, PTT service talk among conference room members or groups in the conference room is implemented. Embodiments of the present invention also disclose another method for implementing the PTT service, as well as a terminal, a conference application server and a system for implementing the PTT service. According to the embodiments of the present invention, the PTT service with wide signal coverage and small call delay is implemented.