Abstract: A computer-implemented method for supporting a blockchain asset issued on a blockchain, the computer-implemented method including: determining, by a blockchain anchor, that an off-chain asset of a particular amount is in a frozen state; issuing, by the blockchain anchor, the blockchain asset on the blockchain, wherein an amount of the blockchain asset is within the particular amount; and publishing, by the blockchain anchor, a transaction record of the blockchain asset in a blockchain ledger of the blockchain, the transaction record containing a freeze certificate for the blockchain asset showing that the blockchain asset is supported by the off-chain asset that has been determined to be in the frozen state.

Abstract: This specification describes techniques for transferring assets between blockchain members. A request for transferring a first amount of blockchain assets between a first user and a second user is received by a first blockchain member of a blockchain. A second blockchain member corresponding to the second user, and a plurality of intermediate blockchain members between the first blockchain member and the second blockchain member are determined by the first blockchain member, where adjacent blockchain members respectively hold blockchain assets issued by a same anchor point. An asset transfer contract operation is initiated by the first blockchain member and based on an asset transfer condition published by each intermediate blockchain member. Whether the asset transfer contract operation takes effect is determined by the first blockchain member. In response to determining that the asset transfer contract operation takes effect, an atomic transaction is performed by the first blockchain member.

Abstract: A blockchain transaction record that is selected from a blockchain account book associated with a blockchain and satisfies a specified condition is obtained by a blockchain member. The blockchain transaction record is compared with an off-chain transaction record maintained by the blockchain member to obtain a comparison value indicating whether the off-chain transaction record is consistent with the blockchain transaction record. If the comparison value indicates that the off-chain transaction record is inconsistent with the blockchain transaction record, the off-chain transaction record is modified based on the blockchain transaction record to make the off-chain transaction record consistent with the blockchain transaction record.

Abstract: Input information associated with a data field is received. The data field is included in a page. A determination is made as to whether the input information includes an error. In response to determining that the input information includes an error an anchor is determined in the page corresponding to a location of the data field in the page. An error popup is displayed on the page. The error popup includes an error list that includes an error notification associated with the error. The error notification includes the location of the data field in the page.

Abstract: A viewing user is provided with social advertisements when accessing content associated with a social networking system. A social advertisement can include a candidate advertisement and an associated social story. Candidate advertisements are advertisements provided by one or more advertisers, where the advertisements each specify a relationship between their advertising content and one or more social networking objects. To identify social stories associated with the candidate advertisements, the social networking system identifies other users associated with the viewing user who has interacted with social networking objects that are related to candidate advertisements. Additionally, the social networking system identifies the one or more interactions between the other users and the one or more objects as a social story.

Abstract: A method for forming an electrocatalyst for fuel cell applications comprises electrolessly depositing a first plurality of nickel particles onto carbon-support particles. The nickel particles are formed from a nickel ion-containing aqueous solution. At least a portion of the nickel particles are replaced with platinum via a galvanic displacement reaction to form a second plurality of nickel particles coated with a platinum layer. During this displacement reaction step, the nickel particles are heated to a temperature sufficient to form the platinum layer. Finally, the second plurality of nickel particles is optionally incorporated into a cathode layer of a fuel cell.

Abstract: An apparatus for the synthesis and treatment of electrocatalyst particles in batch or continuous fashion is provided. In one embodiment, the apparatus is comprised of a three-electrode cell which includes a cell body electrode, a reference electrode and a floating counter electrode. The floating counter electrode may be disposed inside a counter electrode compartment which is adapted to float in a slurry containing a plurality of nanoparticles and an electrolyte.

Abstract: A fuel cell membrane and a method of making the same. The membrane includes at least one non-reinforced layer and at least one reinforced layer. Both layers include a proton-conductive ionomer, while the reinforced layer additionally includes nanofiber-supported catalyst that improve mechanical and chemical durability of the membrane. The nanofiber-supported catalyst is made up of structural fibers onto which an electrocatalyst is coated, deposited or otherwise formed. The structural nanofibers give increased strength and stiffness to the layers that include them, while the electrocatalyst helps to resist electrochemical degradation to the membranes that include them. Such a membrane may form the basis of a fuel cell's membrane electrode assembly.

Abstract: An apparatus and method for synthesis and treatment of electrocatalyst particles in batch or continuous fashion is provided. In one embodiment, the apparatus comprises a sonication bath and a two-compartment chamber submerged in the sonication bath. The upper and lower compartments are separated by a microporous material surface. The upper compartment comprises a cover and a working electrode (WE) connected to a Pt foil contact, with the foil contact connected to the microporous material. The upper chamber further comprises reference counter electrodes. The lower compartment comprises an electrochemical cell containing a solution of metal ions. In one embodiment, the method for synthesis of electrocatalysts comprises introducing a plurality of particles into the apparatus and applying sonication and an electrical potential to the microporous material connected to the WE.

Abstract: Core-shell particles encapsulated by a thin film of a catalytically active metal are described. The particles are preferably nanoparticles comprising a non-noble core with a noble metal shell which preferably do not include Pt. The non-noble metal-noble metal core-shell nanoparticles are encapsulated by a catalytically active metal which is preferably Pt. The core-shell nanoparticles are preferably formed by prolonged elevated-temperature annealing of nanoparticle alloys in an inert environment. This causes the noble metal component to surface segregate and form an atomically thin shell. The Pt overlayer is formed by a process involving the underpotential deposition of a monolayer of a non-noble metal followed by immersion in a solution comprising a Pt salt. A thin Pt layer forms via the galvanic displacement of non-noble surface atoms by more noble Pt atoms in the salt. The overall process is a robust and cost-efficient method for forming Pt-coated non-noble metal-noble metal core-shell nanoparticles.

Abstract: A method of coating carbon based electrodes and thick electrodes without mud-cracking is described. The electrode ink is deposited on a decal substrate, and transferred to a hot press before the electrode ink is completely dried. The partially dried electrode ink is hot pressed to the membrane to form a membrane electrode assembly. A membrane electrode assembly including a polymer membrane; and a pair of crack-free electrode layers on opposite sides of the polymer membrane, each of the pair of electrode layers having a thickness of at least about 50 ?m is also described.

Abstract: A membrane/electrode assembly for fuel cell applications includes an ion conducting polymer and a porphyrin-containing compound at least partially dispersed within the ion conducting polymer, a first electrode and a second electrode. At least one of the first and second electrodes also includes the porphyrin-containing compound. The membrane/electrode assembly exhibits improved performance over membrane/electrode assembly not incorporating such porphyrin-containing compounds.

Abstract: A fuel cell membrane and a method of making the same. The membrane includes at least one non-reinforced layer and at least one reinforced layer. Both layers include a proton-conductive ionomer, while the reinforced layer additionally includes nanofiber-supported catalyst that improve mechanical and chemical durability of the membrane. The nanofiber-supported catalyst is made up of structural fibers onto which an electrocatalyst is coated, deposited or otherwise formed. The structural nanofibers give increased strength and stiffness to the layers that include them, while the electrocatalyst helps to resist electrochemical degradation to the membranes that include them. Such a membrane may form the basis of a fuel cell's membrane electrode assembly.

Abstract: The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

Abstract: An apparatus and method for the synthesis and treatment of electrocatalyst particles in batch or continuous fashion is provided. In one embodiment, the apparatus is comprised of a three-electrode cell which includes a cell body electrode, a reference electrode, and a counter electrode. A slurry containing non-noble metal ions and a plurality of particles is introduced into the apparatus. During operation an electrical potential is applied and the slurry is stirred. When particles in the slurry collide with the electrically conductive region of the cell body electrode the transferred charge facilitates deposition of an adlayer of the desired metal. In this manner film growth can commence on a large number of particles simultaneously. After the non-noble metal ions are deposited onto the particles, they are displaced by noble-metal ions by galvanic displacement. This process is especially suitable for forming catalytically active layers on nanoparticles for use in energy conversion devices.

Abstract: An apparatus and method for synthesis and treatment of electrocatalyst particles in batch or continuous fashion is provided. In one embodiment, the apparatus comprises a sonication bath and a two-compartment chamber submerged in the sonication bath. The upper and lower compartments are separated by a microporous material surface. The upper compartment comprises a cover and a working electrode (WE) connected to a Pt foil contact, with the foil contact connected to the microporous material. The upper chamber further comprises reference counter electrodes. The lower compartment comprises an electrochemical cell containing a solution of metal ions. In one embodiment, the method for synthesis of electrocatalysts comprises introducing a plurality of particles into the apparatus and applying sonication and an electrical potential to the microporous material connected to the WE.

Abstract: A method for forming an electrocatalyst for fuel cell applications comprises electrolessly depositing a first plurality of nickel particles onto carbon-support particles. The nickel particles are formed from a nickel ion-containing aqueous solution. At least a portion of the nickel particles are replaced with platinum via a galvanic displacement reaction to form a second plurality of nickel particles coated with a platinum layer. During this displacement reaction step, the nickel particles are heated to a temperature sufficient to form the platinum layer. Finally, the second plurality of nickel particles is optionally incorporated into a cathode layer of a fuel cell.

Abstract: A method for forming an electrocatalyst for fuel cell applications comprises electrolessly depositing a first plurality of nickel particles onto carbon-support particles. The nickel particles are formed from a nickel ion-containing aqueous solution. At least a portion of the nickel particles are replaced with platinum via a galvanic displacement reaction to form a second plurality of nickel particles coated with a platinum layer. During this displacement reaction step, the nickel particles are heated to a temperature sufficient to form the platinum layer. Finally, the second plurality of nickel particles is optionally incorporated into a cathode layer of a fuel cell.

Abstract: A method of treating electrically conductive nanoparticles using a dynamic processing electrochemical cell.

Abstract: A viewing user is provided with social advertisements when accessing content associated with a social networking system. A social advertisement can include a candidate advertisement and an associated social story. Candidate advertisements are advertisements provided by one or more advertisers, where the advertisements each specify a relationship between their advertising content and one or more social networking objects. To identify social stories associated with the candidate advertisements, the social networking system identifies other users associated with the viewing user who has interacted with social networking objects that are related to candidate advertisements. Additionally, the social networking system identifies the one or more interactions between the other users and the one or more objects as a social story.