摘要:
The productivity of a catalyst in a gas phase polymerization of olefins (e.g. grams of polymer per gram of catalyst) may be increased by including in the gas phase from 1 to 20 weight % of an inert non-polymerizable hydrocarbon. The hydrocarbon may be in gaseous form but preferably is in liquid form.
摘要:
The present invention provides a novel process for preparing a catalyst useful in gas phase polymerization of olefins wherein the physical properties of the polymer and the productivity of the catalyst can be altered depending on the sequence of addition of the catalyst components. The catalyst consists of compounds of Ti, Mg, Al and optionally an electron donor supported on an amorphous support.
摘要:
The present invention provides a novel process for preparing a catalyst, preferably free of electron donor, useful in gas phase polymerization of olefins having a broad polydispersity.
摘要:
The present invention provides a novel process for preparing a catalyst, preferably free of electron donor, useful in gas phase polymerization of olefins having a broad polydispersity.
摘要:
Some properties such as dart impact strength, hexane extractables and resin stickiness of a polyethylene copolymer produced in a gas phase polymerization using a Ziegler-Natta catalyst are better controlled by regulating the ratio of aluminum from the co-catalyst to the polymer production rate. This enables one to improve properties such as dart impact strength and reduce hexane extractables by changing the amount of co-catalyst fed into the reactor.
摘要:
The present invention provides a novel process for preparing a catalyst useful in gas phase polymerization of olefins wherein the physical properties of the polymer and the productivity of the catalyst can be altered depending on the sequence of addition of the catalyst components. The catalyst consists of compounds of Ti, Mg, Al and optionally an electron donor supported on an amorphous support.
摘要:
Embodiments of the present invention are directed to apparati and associated methods for an easy on-off device to support and provide direct therapeutic cooling relief to the affected genitalia of persons having post-operative pain and swelling.
摘要:
Methods and systems of managing meetings may involve intercepting an outgoing message from a sender to a recipient, and conducting an analysis of the outgoing message with respect to a calendar associated with the sender. In addition, delivery of the message may be suspended if the analysis indicates that the sender and the recipient have a scheduled meeting. In one example, the outgoing message includes at least one of an email message, a chat message and a text message.
摘要:
Acclimatizing a user to a scheduling pattern change includes: in a calendar system implemented by at least one processor, determining an anticipated scheduling pattern change for the user; establishing with the calendar system an acclimatization period to transition the user to the scheduling pattern change; receiving in the calendar system a request to schedule an event for the user at a time within the acclimatization period; and prompting the user to reschedule the event to a time outside of the acclimatization period with the calendar system.
摘要:
The invention provides a method for obtaining a binding compound for a protein family, wherein the members of the protein family bind a common ligand. The method includes the steps of (a) providing a sample containing a protein from the protein family, a first ligand and a second ligand under conditions wherein the first ligand, the second ligand and the protein form a bound complex; (b) detecting magnetization transfer between the first ligand and the second ligand in the bound complex, thereby determining that the two ligands are proximal in the bound complex; and (c) obtaining a candidate binding compound including the first ligand, or a fragment thereof linked to the second ligand, or a homolog thereof, whereby the population contains binding compounds that bind to members of the protein family.