Abstract: A method for testing and controlling a rapid shutdown device, and a tester are provided. The method includes: transmitting a heartbeat signal of first signal strength to a target rapid shutdown device in a target rapid shutdown module to switch the target rapid shutdown device on and testing the target rapid shutdown device using a preset testing program t, on receipt of a rapid shutdown device testing request, where all rapid shutdown devices in the target rapid shutdown module are previously off; and transmitting a heartbeat signal of second signal strength to the target rapid shutdown module to switch the rapid shutdown devices on or off, on receipt of a rapid shutdown device control request, where the first signal strength is lower than the second signal strength. The rapid shutdown devices can be tested and controlled efficiently, thereby effectively avoiding safety hazards and thus protecting workers.

Abstract: A surgical stapler includes an anvil and a cartridge that cooperate with each other, a handle, and a connecting tube for connecting the cartridge to the handle. A stent mounting rod is arranged at a front end of the anvil, and a stent for distracting an orifice is movably connected to the stent mounting rod. The stent has a flexible and deformable tubular structure and can distract a lumen of the human orifice after a radial constraint is removed. The stent is coated with an anti-leakage film. An anti-reflux film is further arranged on the stent. The surgical stapler can effectively solve some complications after anastomosis by an existing surgical stapler, and can be widely used in the technical field of medical anastomosis.

Abstract: A core-shell gradient ternary precursor and a preparation method and application thereof. The preparation method includes (1) mixing a terephthalic acid solution with alkaline liquor to obtain a terephthalic acid salt solution, adding a nickel source solution for a reaction to obtain a Ni-MOF solution, mixing the Ni-MOF solution with ammonia water, and adjusting a pH value to obtain a base solution; and (2) adding a nickel-cobalt-manganese ternary mixed salt solution, a liquid alkali solution, and an ammonia-water solution simultaneously to the base solution obtained in step (1) for a co-precipitation reaction, and obtaining the core-shell gradient ternary precursor after aging treatment. The Ni-MOF is pre-prepared and used as a core for the co-precipitation reaction, to obtain the core-shell like precursor with a gradient. Carbon in the core of the core-shell gradient ternary precursor reacts with oxygen, thereby reducing a nickel oxidation state on particle surfaces and reducing crack generation.

Abstract: Embodiments in the present description provide an operation request processing method and apparatus, and a device, and a readable storage medium, and a system. In the present embodiment, after obtaining an operation request for a data table, a read-write node can return a request processing completion message to a requester in time without waiting for all read-only nodes; a locking operation is performed on the data table, a log of locking the data table is written into a redo log file; and after status information of the log of locking is written into a status record, a monitoring processing process can achieve log playback monitoring of all the read-only nodes by using the status record and the log of locking. Thus, an asynchronous processing mechanism is achieved, and the stability and efficiency of operation request execution are improved.

Abstract: A closed variable-frequency heat pump drying device with a heat regenerator includes a variable-frequency compressor, a condenser, a throttling valve, an evaporator, a heat regenerator, a three-way valve, a variable-frequency fan, an air inlet temperature sensor, an air inlet humidity sensor, a drying bin, an air outlet temperature sensor, an air outlet humidity sensor and a controller. The controller regulates frequency of the variable-frequency compressor by comparing magnitudes of actual and set air inlet temperatures; a ratio of a straight-through air volume to a regenerated air volume of the three-way valve by comparing magnitudes of actual and set air inlet humidity; and frequency of the variable-frequency fan by comparing magnitudes of actual and set air humidity difference and magnitudes of actual and set air temperature difference of medium air entering and exiting the drying bin.

Abstract: A polyethylene composition having from about 0.5 to about 20 wt % of alpha-olefin derived units other than ethylene-derived units, with the balance including ethylene-derived units, total internal unsaturations (Vy1+Vy2+T1) of from about 0.15 to about 0.40 per 1000 carbon atoms, an MI of from about 0.1 to about 6 g/10 min, an HLM1 of from about 5.0 to about 40 g/10 min, a density of from about 0.890 to about 0.940 g/ml, a Tw1-Tw2 value of from about ?50 to about ?23° C., an Mw1/Mw2 value of from about 2.0 to about 3.5, an Mw/Mn of from about 4.5 to about 12, an Mz/Mw of from about 2.5 to about 3.0, an Mz/Mn of from about 15 to about 25, and a g?(vis) greater than 0.90.

Abstract: This invention relates to a supported catalyst system comprising: (i) at least one first catalyst component comprising a group 4 metallocycle containing metallocene complex; (ii) at least one second catalyst component comprising a 2,6-bis(imino)pyridyl iron complex; (iii) activator; and (iv) support. The catalyst system may be used for preparing polyolefins, such a bimodal polyethylene, typically in a gas phase polymerization.

Abstract: This invention relates to a supported catalyst system comprising: (i) at least one first catalyst component comprising a group 4 bis(phenolate) complex; (ii) at least one second catalyst component comprising a 2,6-bis(imino)pyridyl iron complex; (iii) activator; and (iv) support. The catalyst system may be used for preparing polyolefins, such a bimodal polyethylene, typically in a gas phase polymerization.

Abstract: Catalyst systems and methods for making and using the same. A method of polymerizing olefins to produce a polyolefin polymer with a multimodal composition distribution, includes contacting ethylene and a comonomer with a catalyst system. The catalyst system includes a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system. The first catalyst compound includes a compound with the general formula (C5HaR1b)(C5HcR2d)HfX2. The second catalyst compound comprises the following formula: wherein each R3 or R4 is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R3 or R4 may be the same or different, and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R3 group.

Abstract: A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.

Abstract: The present disclosure generally relates to catalyst systems, polyethylene compositions, and uses of such compositions in, e.g., films. In an embodiment is provided a film that includes a polyethylene composition, comprising: ethylene and a C3-C40 olefin comonomer, the polyethylene composition having at least 75 wt % ethylene content and from 0 wt % to 25 wt % of a C3-C40 olefin comonomer content based upon the total weight of the composition as determined by GPC-IR5-LS-VIS, the film having: an average of MD and TD 1% secant modulus of 42,000 psi or greater as determined by ASTM D-882, and a Dart Drop Impact of greater than 400 g/mil, as determined by ASTM D1709.

Abstract: The present disclosure generally relates to catalyst systems, polyethylene compositions, and uses of such compositions in, e.g., films. In an embodiment is provided a film that includes a polyethylene composition, comprising: ethylene and a C3-C40 olefin comonomer, the polyethylene composition having at least 65 wt % ethylene content and from 0 wt % to 35 wt % of a C3-C40 olefin comonomer content based upon the total weight of the composition, the film having: an average of MD and TD 1% secant modulus of 43,000 psi or greater, and a Dart Drop Impact Strength of greater than 500 g/mil. In another embodiment is provided a process for producing a polyethylene composition that includes introducing ethylene and a C3-C40 alpha-olefin to a catalyst system, the catalyst system comprising a first catalyst compound, a second catalyst compound, and an activator; and forming a polyethylene composition.

Abstract: Provided herein are polyethylene films made of the polyethylene blends having improved properties, particularly in Elmendorf tear and puncture resistance. The polyethylene blends include two primary polyethylene blends.

Abstract: Embodiments relate to polyolefin compositions containing one or more high-density polyethylenes (HDPEs) and linear low-density polyethylenes (LLDPEs) and methods for forming the same. The polyolefin composition contains about 40 wt % to about 60 wt % of HDPE and about 40 wt % to about 60 wt % of LLDPE, by weight of the polyolefin composition. The HDPE has a density of greater than 0.93 g/cm3 and a melt index of about 0.2 dg/min to about 10 dg/min. The LLDPE has a density of less than 0.915 g/cm3 and a melt index of about 0.2 dg/min to about 10 dg/min. The polyolefin composition has a density of about 0.91 g/cm3 or greater, a melt index of about 0.5 dg/min to about 6 dg/min, and a Tw1?Tw2 value of about ?25° C. or less.

Abstract: The present disclosure provides a cup lid and a self-producing water cup. The cup lid includes: a housing, a condensing mechanism, and a heat dissipation mechanism. The housing defines a housing space, an air inlet, an air outlet, and a water outlet. The air inlet, the air outlet, and the water outlet are connected to an outside. The air inlet, the air outlet, and the water outlet are connected to the housing space. The condensing mechanism is housed in the housing and connected to the air inlet. The condensing mechanism is configured to condense air flowing from the air inlet into water, and the water flows out through the water outlet. The heat dissipation mechanism is housed in the housing and connected to the air outlet. The heat dissipation mechanism is configured to dissipate heat generated by the condensing mechanism.

Abstract: A polyethylene comprising of ethylene derived units and 0.5 wt % to 10 wt % C3 to C12 ?-olefin derived units may be synthesized using a mixed catalyst that comprises rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride and a zirconium co-catalyst in a mole ratio of 50:50 to 90:10, and wherein the zirconium co-catalyst is a poor comonomer incorporator as compared to the rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride catalyst. Such a polyethylene may have a density of 0.91 g/cm3 to 0.93 g/cm3, an I2 value of 0.5 g/10 min to 2 g/10 min, an I21 value of 25 g/10 min to 75 g/10 min, an I21/I2 ratio of 25 to 75, a molar reversed-co-monomer index (RCI,m) of 30 to 180, a phase angle equal or lower than 70° at complex modulus G* of 10,000 Pa, a ?2 of 1.5 radians to ?1.5 radians, and a low density population of 50% and 70% by weight of the polyethylene.

Abstract: A polyethylene suitable for use in blown film can comprise ethylene derived units and C3 to C12 ?-olefin derived units at 0.5 wt % to 10 wt % of the polyethylene and have a reversed-co-monomer index (RCI,m) of 35 to 100, a comonomer distribution ratio (CDR-2,m) of 1.20 to 1.80, and a weight average molecular weight (Mw) to number average molecular weight (Mn) of 5 to 7.

Abstract: The present disclosure provides a cup lid and a self-producing water cup. The cup lid includes: a housing, a condensing mechanism, and a heat dissipation mechanism. The housing defines a housing space, an air inlet, an air outlet, and a water outlet. The air inlet, the air outlet, and the water outlet are connected to an outside. The air inlet, the air outlet, and the water outlet are connected to the housing space. The condensing mechanism is housed in the housing and connected to the air inlet. The condensing mechanism is configured to condense air flowing from the air inlet into water, and the water flows out through the water outlet. The heat dissipation mechanism is housed in the housing and connected to the air outlet. The heat dissipation mechanism is configured to dissipate heat generated by the condensing mechanism.

Abstract: A polyethylene composition comprising from about 0.5 to about 20 wt % of alpha-olefin derived units other than ethylene-derived units, with the balance including ethylene-derived units, total internal unsaturations (Vy1+Vy2+T1) of from about 0.10 to about 0.40 per 1000 carbon atoms, an MI of from about 0.1 to about 6 g/10 min, an HLMI of from about 5.0 to about 40 g/10 min, a density of from about 0.890 to about 0.940 g/ml, a Tw1-Tw2 value of from about ?25 to about ?20° C., an Mw1/Mw2 value of from about 1.2 to about 2.0, an Mw/Mn of from about 4.5 to about 12, an Mz/Mw of from about 2.0 to about 3.0, an Mz/Mn of from about 7.0 to about 20, and a g?(vis) greater than 0.90.

Abstract: This invention relates to a supported catalyst system comprising: (i) at least one first catalyst component comprising a group 4 bis(phenolate) complex; (ii) at least one second catalyst component comprising a 2,6-bis(imino)pyridyl iron complex; (iii) activator; and (iv) support. The catalyst system may be used for preparing polyolefins, such a bimodal polyethylene, typically in a gas phase polymerization.