Abstract: This application provide a data management method for a blockchain system, a medium, and an electronic device. The system includes an accounting node sub-network and a service node sub-network. The method includes: adding, after an accounting node generates a first data block, first key information used for verifying a block header of a second data block generated after the first data block to a block header of the first data block; generating a signature corresponding to the first data block, and adding the signature corresponding to the first data block to the block header of the first data block; and releasing the block header of the first data block to the service node sub-network, to cause a service node to verify the signature included in the block header of the first data block, and obtaining the first key information after a successful verification to verify the block header of the second data block.

Abstract: A process for purifying a gaseous feed stream of natural gas including methane, CO2 and heavy hydrocarbons including step a): cooling the gaseous feed stream in a heat exchanger; step b): introducing the cooled stream into a phase-separating chamber to produce a liquid stream depleted in methane and enriched in heavy hydrocarbons and a gaseous stream; step c): separating the gaseous stream obtained from step b) in a first membrane producing at least one CO2-enriched permeate stream and a residual stream enriched in methane; step d): introducing the residual stream obtained from step c) into a phase-separator to produce a liquid stream and a gaseous stream; step e): heating the gaseous stream obtained from step d) by introducing it into the heat exchanger used in step a) counter-currentwise with the feed stream thereby producing a gaseous stream depleted in CO2 and enriched in methane.

Abstract: A jig for inspecting a display module, the display module including a display module body and a lug, the jig including a bottom plate and a cover plate, the cover plate operatively covering the bottom plate; the bottom plate being provided with a first flat portion and the cover plate being provided with a second flat portion, wherein the bottom plate is provided with a first concave portion surrounded by the first flat portion, and/or the cover plate provided with a second concave portion surrounded by the second flat portion, the first concave portion and/or the second concave portion form(s) a receiving area for the display module body, and the first flat portion and the second flat portion are configured to clamp the lug.

Abstract: The present disclosure provides a method for preparing a perovskite quantum dot film by one-step crystallization, and belongs to the field of perovskite quantum dot material technology. The present disclosure uses adamantanemethylamine and hydrohalic acid as ligands, first mixes a cesium halide, a lead halide, and the ligands with a solvent to obtain a precursor solution, then deposits the precursor solution on a substrate, and then heats the substrate to obtain the CsPbX3 perovskite quantum dot film. The present disclosure uses adamantanemethylamine and hydrohalic acid as the ligands, which can quickly coat the perovskite, complex with the CsPbX3 perovskite, and directly form the perovskite quantum dot via a strong steric effect. Further, the present disclosure is simple and inexpensive, can directly obtain a high-quality perovskite quantum dot film with a thickness of more than 500 nm by one-step crystallization.

Abstract: Embodiments of this disclosure disclose a resource transfer data management method and apparatus, and a storage medium, which belong to the field of Internet technologies. The method includes: receiving transaction data transmitted by a first server, wherein the transaction data is obtained by the first server by signing resource transfer data according to a private key of the first server; verifying the transaction data according to a public key of the first server; and generating a second block according to the transaction data and a feature value of a first block in a blockchain when the verification succeeds, and adding the second block as a next block of the first block to the blockchain.

Abstract: In a transaction method, transaction information is obtained. The transaction information includes a type identifier and quantity of first assets, and a type identifier and quantity of second assets. Transaction records, corresponding to a transaction in a block, are stored upon verification of the transaction information. The transaction records include first and second transaction records. The first transaction record includes first input and output items corresponding to the first assets, and the first input and output items each includes the type identifier of the first assets. The second transaction record includes second input and output items corresponding to the second assets, and the second input and output items each includes the type identifier of the second assets. The block is broadcasted to other nodes in the blockchain network, and verification results are received. The block is added to a blockchain of a current node based on the verification results.

Abstract: A data backup method includes querying a first block of a first blockchain for unused transaction output information based on a first condition being met, the first block including each block of all blocks included in the first blockchain; generating transaction information according to the unused transaction output information obtained based on the querying, the transaction information indicating a transaction operation based on an account address to which the unused transaction output information belongs; recording the transaction information in a second block and releasing the second block, and recording the second block on which a consensus is reached on a second blockchain; and backing up the first blockchain into a storage system, and deleting the first blockchain. Counterpart apparatus, terminal, server, and/or non-transitory computer-readable medium are also contemplated.

Abstract: A method for electing a representative node device performed by a first node device in a blockchain system includes: broadcasting candidate addition transaction data in the blockchain system, the candidate addition transaction data carrying credential data, the credential data being received from a target server and indicating that a first node device meets a qualification requirement for a candidate node device; storing the candidate addition transaction data on a target blockchain of a blockchain system when a plurality of node devices in the blockchain system verify the candidate addition transaction data by consensus; and participating in an election of the representative node device according to the candidate addition transaction data stored on the target blockchain.

Abstract: A method for electing a representative node device is performed at a blockchain system, including: obtaining voting transaction data from the node devices, the voting transaction data being used for voting for one or more node devices of the blockchain system as representative node devices; generating and storing the voting transaction data into a target blockchain of the blockchain system when a plurality of node devices of the blockchain system verify the voting transaction data by consensus; and when a quantity of blocks in the target blockchain generated using the voting transaction data reaches a preset quantity, determining an election result according to quantities of votes of the node devices determined from the voting transaction data, the election result identifying a plurality of representative node devices in the blockchain system being configured to generate new blocks for the target blockchain and perform verification on the new blocks by consensus.

Abstract: A method for electing a representative node device for a blockchain system includes: receiving IP address information of a first node device, the first node device being in a candidate state for a representative node device; receiving, from the first node device, an IP address obtaining request for requesting IP address information of a representative node device; when the first node device is determined to be a representative node device of the blockchain system elected in a current election process, transmitting, to the first node device, an IP address list comprising IP address information of representative node devices elected in the current election process; and when the first node device is determined not to be a representative node device of the blockchain system elected in the current election process, skipping the IP address obtaining request.

Abstract: Natural gas may be purified by removing C3+ hydrocarbons and CO2 in respective one or more separation units to yield conditioned gas lower in C3+ hydrocarbons and CO2 in comparison to the un-conditioned natural gas. Notably, the feed gas need not be subjected to joule-thomson expansion and molecular sieve dehydration performed by conventional processes. Rather, any water-rich reject stream from the separation unit(s) is dried downstream with a smaller compressor and smaller molecular sieve or gas separation membrane dehydration unit before it may be re-injected deep underground or deep under the sea bed.

Abstract: A bipolar plate of a proton exchange membrane fuel cell is prepared from graphite powder, thermosetting resin and an electrically conductive polymer. The electrically conductive polymer has good electrically conductive properties, and can be cured by heating, which improves the strength and air tightness while ensuring the electrical conductivity of the graphite/thermosetting resin composite bipolar plate. A method of preparing the bipolar plate is further provided, including dispersing the graphite powder in a first organic solvent to obtain a first mixture; dispersing the electrically conductive polymer in a second organic solvent to obtain a second mixture; uniformly mixing the first mixture and the second mixture followed by heating and drying to obtain a powder mixture; mixing, the powder mixture and the thermosetting resin followed by ball milling, thermal press curing, cooling and demolding to obtain the bipolar plate.

Abstract: Nitrogen is removed from biogas using a three-stage separation system based on gas separation membranes. The first stage separates a biomethane feed stream into a first permeate gas stream and a first retentate gas stream. The second stage separates the first permeate stream into a biomethane product gas and a first low quality biomethane gas stream. The third stage separates the first retentate into a second low quality biomethane gas stream and a waste gas. A biogas feed stream is pretreated to remove amounts of water, VOCs, and CO2 to yield a methane-enriched biogas stream. The methane-enriched biogas stream is compressed together with the first and second low quality biomethane gas streams to form the biomethane feed stream.

Abstract: A method for improvement of magnetic performance of sintered NdFeB magnet includes the following steps. Firstly, material containing element R, H and X is to be covered on a surface of the sintered NdFeB magnet to form a finish coat. After that, proceed with a diffusion treatment and an aging treatment to the sintered NdFeB magnet with the finish coat in the environment of vacuum or inert gas. R is at least one of such elements as Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. H is hydrogen. X is at least one of such elements as C, O, N, S, B, Cl and Si.

Abstract: A liquid hydrocarbon fuel containing dissolved oxygen is at least partially deoxygenated with a membrane device comprising a composite hollow fiber membrane that is comprised of an ultra-thin amorphous fluoropolymer layer superimposed on a porous PEEK polymer substrate.

Abstract: A liquid hydrocarbon fuel containing dissolved oxygen is at least partially deoxygenated with a membrane device comprising a composite hollow fiber membrane that is comprised of an ultra-thin amorphous fluoropolymer layer superimposed on a porous PEEK polymer substrate.

Abstract: A process for purifying a feed gas including methane and heavy hydrocarbons, including: step a): cooling the feed gas in a heat exchanger; step b): introducing the resulting into a first phase separator to produce a liquid stream depleted in methane and enriched in heavy hydrocarbons and a gas stream; step c): separating the gas stream in a membrane from which a methane-enriched permeate stream and a partially condensed residue stream exit; step d): introducing the residue stream from step c) into a second phase separator vessel in order to produce a liquid stream and a gas stream; step e): introducing at least one portion of the gas stream resulting from step d) into a JT expansion means; and step f): heating at least one portion of the expanded stream in the heat exchanger used in step a) counter-current to the feed stream in order to cool the latter.

Abstract: The invention relates to a process for recovering methane from digester biogas or landfill gas. More specifically, the invention pertains to a method for producing biomethane that removes impurities from a compressed digester biogas with staged membrane modules of at least two different types, to produce a biomethane having at least 94% CH4, below 3% of CO2, and below 4 ppm of H2S.

Abstract: The present application relates to an easy-to-install LED double-ring ceiling lamp, including a base plate, a LED light source board, a driving power supply, a translucent cover and a press ring. The LED light source board and the driving power supply are installed on the base plate, the translucent cover is covered on the base plate, and the press ring is covered outside the translucent cover and configured to support the translucent cover. The press ring and the base plate are detachably connected by multiple installation column-shaped bolts, and at least one of the multiple installation column-shaped bolts is a bendable installation column-shaped bolt.

Abstract: The present application relates to an easy-to-install LED double-ring ceiling lamp, including a base plate, a LED light source board, a driving power supply, a translucent cover and a press ring. The LED light source board and the driving power supply are installed on the base plate, the translucent cover is covered on the base plate, and the press ring is covered outside the translucent cover and configured to support the translucent cover. The press ring and the base plate are detachably connected by multiple installation column-shaped bolts, and at least one of the multiple installation column-shaped bolts is a bendable installation column-shaped bolt.