Abstract: An electrolytic method for suppressing liquid eluent containing previously separated sample analyte anions, counterions to the sample anions, and non-sample anions suppressible to weak acids in an electrolytic device comprising a housing defining at least a sample stream flow channel and an ion receiving flow-through channel separated by an ion exchange bather. The sample stream flow channel includes an upstream channel portion and a downstream channel portion. A first current is applied across the upstream channel portion for substantially completely suppression. A second current is applied across the downstream channel portion at a magnitude of less than 10% of the magnitude of the first current.

Abstract: An electrolytic device comprising a housing includes at least first and second adjacent liquid flow-through channels. A bather impermeable to ion flow and to bulk liquid flow is disposed between the first and second channels. A first electrode assembly is disposed adjacent to one end of the channels and a second electrode assembly is disposed adjacent the other end of the channels. Also, a contaminant removal method using the above electrolytic device. A first aqueous stream including contaminants flows through the first channel while passing a current between the first and second electrode assemblies to remove contaminants. Effluent from the first channel flows, with or without further treatment, through the second channel while passing current between said first and second electrode assemblies to remove further contaminants.

Abstract: An extraction cell assembly includes a cell body, a cap assembly having a cap body and a cap insert, a bed support and a seal. The cap body is removably secured to the cell body and includes a throughbore and a peripheral wall. The cap insert includes a plunger, a peripheral flange extending outwardly from the plunger, and a recess disposed within the plunger. The flange and plunger of the cap insert are slidably received, respectively, inside the peripheral wall and throughbore of the cap body. The bed support is removably received within the recess. The seal is removably received within the throughbore. The seal forms a fluid seal between the cell body and the cap assembly when the cap assembly is secured to the cell body. A method of using the extraction cell assembly is also disclosed.

Abstract: The present invention provides a new design for high capacity stationary phases for chromatography, for example, ion chromatography. The stationary phases include a first polymer layer in contact with and at least partially coating the substrate of the stationary phase. The first polymer layer serves as a foundation for the attachment, and in various embodiments, the growth and attachment, of a highly hyperbranched polymer structure, typically based on one or more products of condensation polymerization. Multiple components are of use in forming the first polymer layer and the hyperbranched polymer structure, thereby providing a stationary phase that can be engineered to have a desired property such as ion capacity, ion selectivity, and the like. Exemplary condensation polymers are formed by the reaction of at least one polyfunctional compound with at least one compound of complimentary reactivity, e.g., a nucleophilic polyfunctional compound reacting with an electrophilic compound.

Abstract: A method for pretreating and extracting a liquid sample by sorbing an aqueous liquid sample, including an organic analyte and an acid or a base, in a solid sorbent material, and at least partially neutralizing the acid or base by reaction with neutralizing ions retained on a support surface, and contacting the liquid sample-sorbed sorbent material at elevated temperature and pressure with an organic solvent to extract the analyte into said solvent, preferably in a vessel having an extraction chamber with a zirconium metal interior surface.

Abstract: An electrolytic device, e.g. a suppressor, including at least two flow-through channels separated by a charged membrane barrier, and a catalyst, for combining hydrogen and oxygen gas, together with ion exchange material, disposed in one of the channels. Also, a method for simultaneous electrolysis and catalytic gas elimination in a channel of the device is described.

Abstract: The present invention provides a new design for high capacity stationary phases for dianion selective ion chromatography. The stationary phases include one or more layers which are products of condensation polymerization. Multiple components are of use in forming the first polymer layer and the condensation polymer structure, thereby providing a stationary phase that can be engineered to have a desired property such as ion capacity, ion selectivity, and the like. Exemplary condensation polymers are formed by the reaction of at least one polyfunctional compound with at least one compound of complimentary reactivity, e.g., a nucleophilic polyfunctional compound reacting with an electrophilic compound.

Abstract: This invention relates to an improved process for the preparation of green fatty acid methyl esters (FAME; commonly called as biodiesel) from different triglyceride oils using mixed metal oxides derived from layered double hydroxides (referred here as LDHs) as reusable solid heterogeneous base catalysts. This process uses very low alcohohoil molar ratio and catalyst and/or products are easily separable after the reaction through simple physical processes. The properties of thus obtained biodiesel meet the standard biodiesel values and can directly be used as transport fuel.

Abstract: An electrolytic device comprising: a central sample flow channel, first and second regenerant flow channels, first and second charged barriers disposed between said sample flow channel and first and second regenerant flow channels, and pairs of oppositely charged, spaced electrodes disposed in the regenerant flow channels. Also, electrolytic devices with a different electrode configuration are described. Also, methods of using the devices, e.g., for suppression in an ion chromatography system are described.

Abstract: An electrolytic device includes four channels separated by three charged barriers. The device can be used to suppress an eluent stream containing separated sample analyte ions and/or to pretreat a sample stream containing unseparated analyte ions.

Abstract: A speakerphone having transmit path with a microphone and a first amplifier having a gain determined by a controller and an input coupled to the microphone, a receive path with a second amplifier having a gain determined by the controller and a speaker coupled to an output of the second amplifier, and operable in a half-duplex mode using an adaptive echo canceller to at least partially remove from the transmit path acoustically-coupled signals from the receive path. The controller increases the gain of the first amplifier and decreases the gain of the second amplifier when a level of signals in the transmit path exceed a level of signals in the receive path, and decreases the gain of the first amplifier and increases the gain of the second amplifier when the level of signals in the receive path exceed the level of signals in the transmit path.

Abstract: A sandwich suppressor in an ion chromatography system in which loosely packed ion exchange resin of low density is disposed in the central sample stream flow channel. Also, a method of using the suppressor is described.

Abstract: A parallel accelerated solvent extraction system includes a plurality of extraction cells, a temperature controlled zone for maintaining the plurality of extraction cells at a desired temperature, a plurality of collection vessels, each fluidly coupled to a respective extraction cell via a flow restrictor configured to maintain a pressure, a solvent pump for supplying extraction solvent to the plurality of extraction cells, and a switching valve for sequentially directing extraction solvent flowing from the solvent pump to respective ones of the plurality of extraction cells. A method of parallel accelerated solvent extraction is also disclosed.

Abstract: A chromatographic method including chromatographically separating sample ionic species in an eluent stream, detecting the separated sample ionic species, catalytically combining hydrogen and oxygen gases or catalytically decomposing hydrogen peroxide in a catalytic gas elimination chamber, and recycling the effluent stream from the chamber to the chromatography separation column. The residence time between the detector and the chamber is at least about one minute. Also, flowing the recycle sequentially through two detector effluent flow channels of an electrolytic membrane suppressor. Also, applying heat or UV energy between the detector and the chamber. Also, detecting bubbles after the chamber. Also, a Platinum group metal catalyst and ion exchange medium in the chamber. Apparatus for performing the methods.

Abstract: A chromatographic method including chromatographically separating sample ionic species in an eluent stream, detecting the separated sample ionic species, catalytically combining hydrogen and oxygen gases or catalytically decomposing hydrogen peroxide in a catalytic gas elimination chamber, and recycling the effluent stream from the chamber to the chromatography separation column. The residence time between the detector and the chamber is at least about one minute. Also, flowing the recycle sequentially through two detector effluent flow channels of an electrolytic membrane suppressor. Also, applying heat or UV energy between the detector and the chamber. Also, detecting bubbles after the chamber. Also, a Platinum group metal catalyst and ion exchange medium in the chamber. Apparatus for performing the methods.

Abstract: An IC system including sample preparation. The system includes a liquid sample injection loop, an ion concentrator, an ion separator, and only a single pump for pumping fluid through the system.

Abstract: An apparatus for detecting analytes in a liquid sample may include an elongated primary channel through which an ionic species flows, the primary channel extending through a primary channel member, a first regenerant channel through which a regenerant flows, the first regenerant channel extending adjacent to the primary channel and being formed in a first block, a first charged barrier having exchangeable ions capable of passing ions of only one charge, positive or negative, and of blocking bulk liquid flow, the first charged barrier disposed between the primary channel member and the first block for separating the primary channel from the first regenerant channel, and a first sealing member disposed between the first charged barrier and the first block defining the first regenerant channel.

Abstract: A method of extracting an analyte from a sample is described. The sample is added to a sample container. A liquid solvent and a gas are added into the sample container. The addition of the gas is controlled to establish an elevated pressure within the sample container. The liquid solvent is heated to an elevated temperature that is below the boiling temperature of the liquid solvent at the elevated pressure. A type of gas is used that does not transition to a supercritical fluid at the elevated temperature and pressure used in the extraction process. The analyte can dissolve from the solid sample into the liquid solvent. Next, at least a portion of the liquid solvent containing the dissolved analyte can be removed from the sample container for subsequent analysis.

Abstract: A non-electrolytic method and apparatus for treating an aqueous sample stream including analyte ions and matrix ions of opposite charge, for pretreatment or suppression. The apparatus includes an ion exchange membrane capable of passing only ions of opposite charge to the analyte ions, a sample stream flow channel, a first aqueous stream ion receiving flow channel adjacent one side of the sample stream flow channel and separated therefrom by the first ion exchange membrane, and stationary flow-through ion exchange packing disposed in the sample stream flow channel. The ion receiving channel has an ion exchange capacity for the matrix ions less than about 25% of the ion exchange capacity for the matrix ions.

Abstract: A speakerphone having transmit path with a microphone and a first amplifier having a gain determined by a controller and an input coupled to the microphone, a receive path with a second amplifier having a gain determined by the controller and a speaker coupled to an output of the second amplifier, and operable in a half-duplex mode using an adaptive echo canceller to at least partially remove from the transmit path acoustically-coupled signals from the receive path. The controller increases the gain of the first amplifier and decreases the gain of the second amplifier when a level of signals in the transmit path exceed a level of signals in the receive path, and decreases the gain of the first amplifier and increases the gain of the second amplifier when the level of signals in the receive path exceed the level of signals in the transmit path.