摘要:
Anion exchange membrane and methods of making and using the same. In one embodiment, the anion exchange membrane may be made by a method that includes a two-step polymerization. In the first step, an α-olefin monomer containing a pendant halide, such as 8-bromo-1-octene, may be polymerized by Ziegler-Natta polymerization to form a first polymer portion, the first polymer portion being a homopolymer. In the second step, the polymerization is charged with a non-functionalized α-olefin monomer, such as ethylene, thereby forming a second polymer portion, the second polymer being a copolymer made up predominantly of the non-functionalized olefin monomer. If desired, a small amount of an α-olefin monomer containing a crosslinking functionality may be included in the first and/or second steps. Following the two-step polymerization, the polymer is fabricated into a thin film. Thereafter, the thin film may be functionalized by replacing the pendant halides with pendant cations.
摘要:
System for gas treatment of cellular implants. The system enhances the viability and function of cellular implants, particularly those with high cellular density, for use in human or veterinary medicine. The system utilizes a miniaturized electrochemical gas generator subsystem that continuously supplies oxygen and/or hydrogen to cells within an implantable and immunoisolated cell containment subsystem to facilitate cell viability and function at high cellular density while minimizing overall implant size. The cell containment subsystem is equipped with features to allow gas delivery through porous tubing or gas-only permeable internal gas compartments within the implantable cell containment subsystem. Furthermore, the gas generator subsystem includes components that allow access to water for electrolysis while implanted, thereby promoting long-term implantability of the gas generator subsystem. An application of the system is a pancreatic islet (or pancreatic islet analogue) implant for treatment of Type 1 diabetes (T1D) that would be considered a bio-artificial pancreas.
摘要:
Membrane electrode assembly and method for fabricating the same. In one embodiment, the method may involve providing an anion exchange membrane and then applying catalyst coatings to opposing surfaces of the anion exchange membrane, whereby a membrane electrode assembly may be formed. Next, the membrane electrode assembly may be subjected to a two-part treatment process. In a first part of the process, the membrane electrode assembly may be swelled, at room temperature, by exposure to an aqueous ethanol solution vapor while being retained under tension in a frame. The aqueous ethanol solution vapor may be, for example, 80:20 by volume ethanol and water. In a second part of the process, the swollen membrane electrode assembly may be removed from the frame and then pressed, at room temperature, between two plates. A layer of rubber and a layer polytetrafluoroethylene may be placed between each plate and the swollen membrane electrolyte assembly.
摘要:
Method and system for detection and quantification of oxidizable organics in water. The method involves the partial electrolytic decomposition of the oxidizable organics in a short time frame, preferably less than five seconds, and does not involve the use of toxic reagents. The system includes an electrochemical sensor probe that, in turn, includes a boron-doped diamond microelectrode array. The system additionally includes an electronic transducer and a computing device. The system utilizes an analysis technique to convert sensor signal to a result that can be correlated with COD or BOD values obtained by standard methods. The method and system are particularly suitable for, but not limited to, use in monitoring of water quality at wastewater treatment plants. By employing the method before and after adding aerobic microorganisms to the sample, the method may be used to distinguish biologically oxidizable organics from total oxidizable organics.
摘要:
A method for the detection of carbon dioxide gas using an electrochemical sensor. The method includes exposing a gas to a sensor, which includes a non-conductive solid substrate and at least one each of a metal oxide sensing electrode, a reference electrode and a counter electrode positioned on the substrate. A solid polymer electrolyte anion-exchange membrane is in intimate contact with the sensing electrode, reference electrode and counter electrode. The method is highly sensitive and selective to carbon dioxide with a very rapid response time.
摘要:
Ternary alloy electrocatalysts comprising platinum and at least two less noble elements are described. The ternary alloy electrocatalysts when employed in the cathode of a fuel cell utilizing a phosphoric acid electrolyte provide improved oxygen activity and stability in comparison to unalloyed platinum. The cost of the electrocatalysts is also reduced in comparison to an unalloyed platinum electrocatalyst.
摘要:
A fast response diffusion-type sensor cell for the detection of carbon monoxide and other oxidizable or reducible gases comprising a three-electrode hydrated proton-conducting membrane cell configuration, with all electrodes in intimate contact with the same proton-conducting membrane is described. The liquid electrolyte-free system has a porous gas-diffusion sensing electrode and a counter electrode located on the same side of and in intimate contact with the proton-conducting membrane. The reference electrode is spatially located on the same or opposite side of the membrane as are the sensing and counter electrodes. The cell configuration is advantageous in that (1) the ionic resistance value between the sensing/reference electrodes is lower than that between the sensing/counter electrodes, and (2) the sensing and counter electrodes being on the same side of the membrane and connected by one or more hydrated proton-exchange membrane channels leads to faster response times and greater immunity to interference from counter electrode reaction products.
摘要:
Atomically dispersed platinum-group metal-free catalyst and method for synthesizing the same. According to one embodiment, the catalyst is made by a method in which, in a first step, a metal oxide/zeolitic imidazolate frameworks (ZIF) composite is formed by combining (i) nanoparticles of an oxide of at least one of iron, cobalt, nickel, manganese, and copper, (ii) a hydrated zinc salt, and (iii) an imidazole. Then, in a second step, the metal oxide/ZIF composite is thermally activated, i.e., carbonized, to form an M-N—C catalyst. Thereafter, the M-N—C catalyst may be mixed with a quantity of ammonium chloride, and then the M-N—C/NH4Cl mixture may be pyrolyzed. The foregoing NH4Cl treatment may improve the intrinsic activity of the catalyst. Then, a thin layer of nitrogen-doped carbon may be added to NH4Cl-treated M-N—C catalyst by chemical vapor deposition (CVD). Such CVD treatment may improve the stability of the catalyst.
摘要:
Method and system for detecting a fungal gene and kit for use with same. According to one embodiment, a nucleotide capture probe is coupled to a surface, such as a well of a 96-well plate, using a biotin-streptavidin interaction. The capture probe is preferably specific for a portion of a target sequence of a fungal gene of interest. Upon capture, additional portions of the target sequence of the fungal gene of interest are tagged with nucleotide labeling probes. An enzyme label, which is preferably a poly-horseradish peroxidase conjugate, is then attached to each of the labeling probes, for example, by a biotin-streptavidin interaction. The enzyme label catalyzes the oxidation of a substrate, such as 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. The oxidized substrate may then be detected photonically, by visually detecting a colorimetric change or by absorbance readings, and/or detected electrochemically in the presence of an acid.
摘要:
Electrolytic gas generator and multi-functional current collector for use in same. In one embodiment, the current collector is constructed both to conduct current from an electrode to a conductive lead and to conduct gas generated at the electrode to external tubing. Accordingly, the current collector may be formed by bonding together a top metal plate and a bottom metal plate of similar profiles, each of which may be shaped to include a main portion and a lateral extension. The bottom metal plate may have central through hole in the main portion for receiving gas from the anode. The top metal plate may have a recess on its bottom surface. The recess may have a first end aligned with the through hole on the bottom metal plate and may have a second end at the end of the lateral extension. A lead and tubing may be attached to the lateral extension.