摘要:
Catalyst compositions comprising a first metallocene compound, a second metallocene compound, an activator-support, and an organoaluminum compound are provided. An improved method for preparing cyclopentadienyl complexes used to produce polyolefins is also provided.
摘要:
The present techniques relate to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene compound comprising bridged η5-cyclopentadienyl-type ligands, typically in combination with a cocatalyst, and an activator. The bridged η5-cyclopentadienyl-type ligands are connected by a cyclic substituent.
摘要:
A method of deriving blood perfusion indices for a region of interest (ROI) of a subject, comprising the steps of administering a contrast agent to the subject during a dynamic imaging scan, converting signal intensity data from raw images of the scan into contrast agent concentration data, deriving parameters from the contrast agent concentration data using at least one transport function that accounts for delay and dispersion of the contrast agent, and calculating the blood perfusion indices from the derived parameters.
摘要:
A liquid dispenser includes a liquid supply channel and a liquid ejector channel that includes an outlet opening. A liquid supply provides a flow of a pressurized liquid through the liquid ejector channel from the liquid supply channel. The pressurized liquid has a momentum as the liquid moves through the liquid ejector channel. A liquid return channel receives the liquid after the liquid passes through the liquid ejector channel. A diverter member forms at least a portion of a wall of the liquid ejector channel. A portion of the diverter member is selectively movable into the liquid flowing through the liquid ejector channel. The momentum of the liquid causes some of the liquid to be diverted through the outlet opening when the portion of the diverter member is moved into the liquid flowing through the liquid ejector channel.
摘要:
This disclosure provides for olefin wax oligomer compositions, methods of producing olefin wax oligomer composition, and methods for oligomerizing olefin waxes. This disclosure encompasses metallocene-based olefin wax oligomerization catalyst systems, including those that include a metallocene and an aluminoxane, a metallocene and a solid oxide chemically-treated with an electron withdrawing anion, and a metallocene, a solid oxide chemically-treated with an electron withdrawing anion, and an organoaluminum compound. The olefin wax oligomers prepared with these catalyst systems can decreased needle penetrations, increased viscosity, and an increased drop melt, making them useful as an additive in candles, stone polishes, liquid polishes, and mold release formulations.
摘要:
A liquid dispenser includes a liquid supply channel, a liquid supply adapted to feed a stream of liquid through the supply channel, a liquid return channel adapted to receive liquid from the supply channel, a liquid dispensing outlet opening, and a diverter member forming at least a portion of a wall of the liquid supply channel, said diverter member being selectively movable to form a convex surface along which liquid remains attached, thereby to divert droplets from the supply channel through the dispensing outlet opening. The motion of the diverter member is substantially orthogonal to the direction of liquid flow, so that energy associated with moving the diverter member imparts no energy to the diverted droplets. The energy associated with moving the diverter member is less than 100 nJ per pL droplet volume.
摘要:
A liquid dispenser includes a liquid supply channel, a liquid supply adapted to feed a stream of liquid through the supply channel, a liquid return channel adapted to receive liquid from the supply channel, a liquid dispensing outlet opening, and a diverter member selectively movable into the supply channel to divert droplets to the dispensing outlet opening. The liquid flows from the liquid supply channel to the liquid return channel by Coanda effect when not diverted. The motion of the diverter member is substantially orthogonal to and opposes the direction of liquid flow, so that energy associated with moving the diverter member imparts no energy to the diverted droplets. The energy associated with moving the diverter member is less than 100 nJ per pL droplet volume. In some embodiments, the energy associated with moving the diverter member is less than 10 nJ per pL droplet volume.
摘要:
A method is disclosed for detecting unfair ratings in rating data over a period of time in connection with an on-line rating system. The method includes the steps of: detecting changes in an arrival rate of ratings in the rating data over the period of time and providing arrival rate change data; detecting changes in a model of the rating data over the period of time such that changes in the model are represented as model errors and providing model error data; detecting changes in a histogram of the rating data over the period of time and providing histogram detection data; detecting changes in a mean of the rating data over the period of time and providing mean change detection data; and processing the arrival rate change data, the model error data, the histogram detection data, and the mean change detection data to identify unfair ratings in the rating data.
摘要:
A method of printing and an apparatus for controlling the directionality of liquid emitted from nozzles of a printhead are provided. Example embodiments of the apparatus include directionality control of liquid jets or liquid drops using a liquid jet directionality control mechanism. Example embodiments of the liquid jet directionality control mechanism include asymmetric energy application device configurations, nozzle geometry configurations, liquid delivery channel geometry configurations, or combinations of these configurations.
摘要:
This invention relates to catalyst compositions, methods, and polymers encompassing at least one Group 4 metallocene compound comprising bridging η5-cyclopentadienyl-type ligands, typically in combination with at least one cocatalyst, and at least one activator. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.