摘要:
This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.
摘要:
This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.
摘要:
This invention relates to a supported nonmetallocene catalyst for olefin polymerization, which is produced by directly reacting a nonmetallocene ligand with a catalytically active metallic compound on a carrier through an in-situ supporting process. The process according to this invention is simple and feasible, and it is easy to adjust the load of the nonmetallocene ligand on the porous carrier. The supported nonmetallocene catalyst according to this invention can be used for olefin homopolymerization/copolymerization, even in combination with a comparatively less amount of the co-catalyst, to achieve a comparatively high polymerization activity. Further, the polymer product obtained therewith boasts desirable polymer morphology and a high bulk density.
摘要:
The present invention relates to a magnesium compound-supported nonmetallocene catalyst, which is produced by directly contacting a catalytically active metallic compound with a nonmetallocene ligand-containing magnesium compound, or by directly contacting a nonmetallocene ligand with a catalytically active metal-containing magnesium compound, through an in-situ supporting process. The process is simple and flexible. In the process, there are many variables in response for adjusting the polymerization activity of the catalyst, and the margin for adjusting the catalyst load or the catalyst polymerization activity is broad. The magnesium compound-supported nonmetallocene catalyst according to this invention can be used for olefin homopolymerization/copolymerization, in combination with a comparatively less amount of the co-catalyst, to achieve a comparatively high polymerization activity. Further, the polymer product obtained therewith boasts high bulk density and adjustable molecular weight distribution.
摘要:
This invention relates to a supported nonmetallocene catalyst for olefin polymerization, which is produced by directly reacting a nonmetallocene ligand with a catalytically active metallic compound on a carrier through an in-situ supporting process. The process according to this invention is simple and feasible, and it is easy to adjust the load of the nonmetallocene ligand on the porous carrier. The supported nonmetallocene catalyst according to this invention can be used for olefin homopolymerization/copolymerization, even in combination with a comparatively less amount of the co-catalyst, to achieve a comparatively high polymerization activity. Further, the polymer product obtained therewith boasts desirable polymer morphology and a high bulk density.
摘要:
The present invention relates to a magnesium compound-supported nonmetallocene catalyst, which is produced by directly contacting a catalytically active metallic compound with a nonmetallocene ligand-containing magnesium compound, or by directly contacting a nonmetallocene ligand with a catalytically active metal-containing magnesium compound, through an in-situ supporting process. The process is simple and flexible. In the process, there are many variables in response for adjusting the polymerization activity of the catalyst, and the margin for adjusting the catalyst load or the catalyst polymerization activity is broad. The magnesium compound-supported nonmetallocene catalyst according to this invention can be used for olefin homopolymerization/copolymerization, in combination with a comparatively less amount of the co-catalyst, to achieve a comparatively high polymerization activity. Further, the polymer product obtained therewith boasts high bulk density and adjustable molecular weight distribution.
摘要:
The invention related to the recycling field of waste printed circuit boards (WPCB), and especially involved a complete non-cyanogens wet process for green recycling of WPCB, which belonged to the field of recycle economy. In the invention, the process included that WPCB were broken by the jaw crusher, and then mixed copper powders and nonmetallic powders were separated by the method of air classification, the mixed copper powders were smelted and casted to get copper anode plates, the copper was purified by electrolytion, the valuable metals (such as copper, gold, silver, platinum and palladium, lead and tin) were recycled from the copper anode slime, and the waste water was recycled. The recovery ratio of all-metal was above 98%. The purity of the cathode copper was up to 4N level. The ratio of de-coppering was above 96%. The recovery ratio of gold was above 98.
摘要:
Tri-level-cell dynamic random access memory (DRAM) stores 3 levels of voltage (0, VDD/2, VDD) into a plurality of memory cells. Selected memory cell connected to bitline (BLT) to develop signal voltage, and adjacent reference bitline (BLR) develops reference voltage at VDD/2. An asymmetrical sensing amplifier (ASA), which has alternative positive offset and negative offset, is used to sense signal voltage and reference voltage for both their difference and sameness. ASA control signals, A and B, switch at different timing points or at different voltage level or the combination of both to have offset voltage set at either positive or negative polarity. Two consecutive read out from one ASA or one single read out from two ASA can be implemented to read memory cells data to local IOs. Output from ASA will be used to restore voltage back to the accessed memory cells.
摘要:
An epitaxial growth method for preventing auto-doping effect is presented. This method starts with the removal of impurities from the semiconductor substrate and the reaction chamber to be used. Then the semiconductor substrate is loaded in the cleaned reaction chamber to be pre-baked under vacuum conditions before the extraction of the dopant atoms desorbed from the surface of the semiconductor substrate. Next, under high temperature and low gas flow conditions, a first intrinsic epitaxial layer is formed on the surface of said semiconductor substrate. Following this, under low temperature and high gas flow conditions, a second epitaxial layer of required thickness is formed on the structural surface of the grown intrinsic epitaxial layer. Last, silicon wafer is unloaded after cooling. This method can prevent auto-doping effect during the epitaxial growth on semiconductor substrate and thus ensure the performance and enhance the reliability of the devices in peripheral circuit region.
摘要:
According to an embodiment of the present invention, a data storage device comprising a motor having a stator is disclosed. The stator may include a substrate having a first surface and a second surface opposite to the first surface; and a n-phase winding arrangement having n phase windings; wherein each phase winding comprises m flat fractional-pitch coils arranged on the first surface of the substrate such that the coils are spaced apart uniformly along a closed loop and connected in series; wherein each coil together with an angular section of the substrate between the coil and an adjacent coil of the same phase winding defines a stator pole-pair; and wherein m is an integer larger than 1.