Abstract:
A fueled cell system comprising: an anode compartment comprising a compound having the formula R1R2N—NR3R4, a salt, a hydrate or a solvate thereof, as fuel, and a catalyst layer which comprises copper or a copper alloy;a cathode compartment comprising an oxidant; and a separator interposed between said cathode and said anode compartments, wherein each of R1-R4 is independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, heteroalicyclic, alkoxy, carboxy, ketone, amide, hydrazide and amine, provided that at least one of R1-R4 is hydrogen.
Abstract:
A system for highly sensitive electrochemical detection of trace nitro-aromatic compounds in air, uses a carbon or carbon/gold working electrode with a surface that is modified to increase the electron transfer kinetics of nitro-aromatic compounds, Chemical modifiers of the working electrode surface include amino-aromatic compounds such as aniline and its derivatives The detection method involves dissolving trace nitro-aromatic compounds in an electrolyte including aprotonic solvents, or dipolar solvents, in the electrochemical cell including a working electrode, a reference electrode and an auxiliary electrode. Voltage is varied across the working electrode and the reference electrode, and an electrical current is measured between the working electrode aid the auxiliary electrode. The measured electrical peak current is a sensitive indication of the concentration of the trace compounds. This invention is appropriate for portable, field-testing of trace explosive compounds in air.
Abstract:
An electrochemical detection system and method for detecting trace explosives, the system including: an electrochemical cell having: (a) a working electrode for providing a current as a function of potential; (b) a reference electrode for providing a reference current as a function of potential; (c) an auxiliary electrode for completing an electric circuit within the cell, and (d) a liquid electrolyte disposed between and interacting with the working electrode, the auxiliary electrode, and the reference electrode, and wherein the electrolyte has a composition including: (i) at least 15%, by weight, of at least one organic solvent for dissolving nitro-aromatic compounds and cyclic nitro-amine compounds, wherein a solubility of RDX in the at least one organic solvent is at least 0.5%, by weight, at 20° C., and (ii) water.
Abstract:
A novel method for preparation of electrodes at a low temperature from electroconducting refractory powder materials. The electrodes are useful for analytical purposes. The method is based on cold pressing of the powders, wetted with solution of a polymer and placed into a disposable frame of the same polymer, with the help of a laboratory hand device producing a relatively small pressure. Control of the end of pressing is done by means of measurement of the electrode resistance. A puncheon serves as a current conductor. Electrodes thus prepared have a low resistance, a high sensitivity and stability. In comparison with glassy carbon electrodes, the most widely applied ones in electroanalytical chemistry, the novel electrodes are cheaper, yet not inferior to such glassy carbon electrodes, and even sometimes better. For example, an electrode prepared from titanium nitride powder has a wider anodic range of potentials and may be used for determination of compounds containing SH-groups, which is impossible to achieve with glassy carbon electrode.
Abstract:
A fuel cell system comprising an anode compartment which comprises an anode having a copper catalyst layer, a cathode configured as an air cathode and a separator interposed between said anode and said cathode, operable by an amine-derived fuel and oxygen (or air) is disclosed. Further disclosed are fuel cell systems comprising an anode compartment which comprises an anode having a copper catalyst layer, a cathode and a separator interposed between said anode and said cathode, which are operable by a mixture of two types of amine-derived compounds (e.g., ammonia borane, hydrazine and derivatives thereof). Also disclosed are methods of producing electric energy by, and electric-consuming devices containing and operable by, the disclosed fuel cell systems.
Abstract:
Fuel cell systems comprising ammonia borane or derivatives thereof as fuel and an anode and/or cathode which comprises a non-noble metal (e.g., copper) or a non-metallic substance (e.g., an iron electron-transfer mediating complex) as a catalyst are disclosed. Fuel cell systems comprising ammonia borane or derivatives thereof as fuel and a peroxide as an oxidant are also disclosed. Uses of the fuel devices are further disclosed.
Abstract:
A fuel cell system comprising an anode compartment which comprises an anode having a copper catalyst layer, a cathode configured as an air cathode and a separator interposed between said anode and said cathode, operable by an amine-derived fuel and oxygen (or air) is disclosed. Further disclosed are fuel cell systems comprising an anode compartment which comprises an anode having a copper catalyst layer, a cathode and a separator interposed between said anode and said cathode, which are operable by a mixture of two types of amine-derived compounds (e.g., ammonia borane, hydrazine and derivatives thereof). Also disclosed are methods of producing electric energy by, and electric-consuming devices containing and operable by, the disclosed fuel cell systems.
Abstract:
A fueled cell system comprising: an anode compartment comprising a compound having the formula R1R2N—NR3R4, a salt, a hydrate or a solvate thereof, as fuel, and a catalyst layer which comprises copper or a copper alloy; a cathode compartment comprising an oxidant; and a separator interposed between said cathode and said anode compartments, wherein each of R1-R4 is independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, heteroalicyclic, alkoxy, carboxy, ketone, amide, hydrazide and amine, provided that at least one of R1-R4 is hydrogen.
Abstract:
Fuel cell systems comprising ammonia borane or derivatives thereof as fuel and an anode and/or cathode which comprises a non-noble metal (e.g., copper) or a non-metallic substance (e.g., an iron electron-transfer mediating complex) as a catalyst are disclosed. Fuel cell systems comprising ammonia borane or derivatives thereof as fuel and a peroxide as an oxidant are also disclosed. Uses of the fuel devices are further disclosed.
Abstract:
An electrochemical system and method for electrochemical detection of both nitro-aromatic and cyclic nitro-amine compounds in a single sample, the system having an electrochemical cell including: (a) a modified working electrode having a surface modified by a chemical modifier; wherein the chemical modifier includes a heterocyclic organic compound in which a heterocycle of the compound includes at least one nitrogen atom.