Abstract: A fully perfluorinated thermoplastic hollow fiber membrane fluid-fluid contactor and a process for manufacturing the contactor is described. The contactor has a unitary end structure produced by a single step potting and bonding process. The contactor can be operated with low surface tension liquids and in harsh chemical environments.

Abstract: High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding a heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Extrusion can be conducted either vertically or horizontally.

Abstract: High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Extrusion can be conducted either vertically or horizontally.

Abstract: A method for forming dendritic metal powders, comprising the steps of: (1) heating a powder comprising non-dendritic particles, under conditions suitable for initial stage sintering, to form a lightly sintered material; and (2) breaking the lightly sintered material to form a powder comprising dendritic particles. In one embodiment, the lightly sintered material is broken by brushing the material through a screen. Another aspect of the present invention comprises the dendritic particles that are produced by the method described above. These particles can comprise any suitable metal, such as transition metals, rare earth metals, main group metals or metalloids or an alloy of two or more such metals. The particles can also comprise a ceramic material, such as a metal oxide. These particles are characterized by a dendritic, highly anisotropic, morphology arising from the fusion of substantially non-dendritic particles, and by a low apparent density relative to the substantially non-dendritic starting material.

Abstract: Systems and methods for determining differential currents in a pair of circuits. In a preferred embodiment, an excitation voltage and a tightly coupled differencing current transformer are coupled to a differential capacitance manometer to generate a differential current. This differential current is input to a low-impedance summing node of a charge amplifier that effectively integrates the differential current. A shielding structure surrounding the current transformer and amplifier is driven to the excitation voltage potential. The output of the charge amplifier is passed through a common mode transformer which is coupled to the excitation voltage source in order to remove the guard potential (corresponding to the excitation signal) from the output signal. A synchronous detector then converts the resulting signal to a DC level indicative of the differential capacitance of the sensor.

Abstract: A connector apparatus is provided which is configured to replace a separation module in a system for dispensing a fluid. When it is desired to purge the system of a dispensed fluid, the connector apparatus, having the same configuration of an inlet and an outlet as the separation module, replaces the separation module and a purging fluid is passed through the system.

Abstract: A connector apparatus is provided which is configured to replace a separation module in a system for dispensing a fluid. When it is desired to purge the system of a dispensed fluid, the connector apparatus, having the same configuration of an inlet and an outlet as the separation module, replaces the separation module and a purging fluid is passed through the system.

Abstract: Compositions and methods for selectively binding specific metal ions, such as Ca2+ and Cd2+, contained in a source solution are disclosed and described. This is accomplished by the use of a composition comprised of an EGTA ligand covalently bonded to a membrane support. The composition formula of the present invention is M—B—L where M is a membrane having a hydrophilic, partially hydrophilic or a composite membrane with a hydrophilic surface, B is a covalent linkage, and L is an EGTA ligand. The separation is accomplished by passing a source solution containing the ions to be separated through a device containing the membrane-ligand composition, causing the selected ions to be complexed to the EGTA ligands and subsequently removing the selected ions from the device by passing an aqueous receiving solution through the device and quantitatively stripping the selected ions from the EGTA ligand.

Abstract: A method for controlling the gas flow within a digital mass flow controller. The method calculates a digitally enhanced flow rate signal that more accurately represents an actual flow rate through the digital mass flow controller. The digitally enhanced flow rate is calculated using a sensed flow rate signal output from a flow sensor, a scaled first derivative of the sensed flow rate signal, and a scaled, filtered second derivative of the sensed flow rate signal. A set-point signal is compared to the digitally enhanced flow rate signal to generate a digital error signal. The digital error signal is provided to a digitally realized PI (proportional integral) controller. The PI controller generates a digital control signal which is used to control a valve in the digital mass flow controller.

Abstract: A system and method for regulating the temperature of a sensor to reduce temperature gradients that form within the sensor. In one embodiment, the temperature gradients are reduced utilizing a temperature regulator with two controlled zones that surround a variable capacitance sensor. Measurements are made for the ambient temperature of at least one of the two temperature controlled zones, and the temperature differential between the two temperature controlled zones. The temperature regulator then adjusts the temperature of the two controlled zones based upon this differential in order to minimize the existing temperature gradient.

Abstract: A plating cell base design that utilizes a single connection that provides both fluid communication and electrical communication to the cell. The design eliminates many of the components previously necessary to effectuate fluid and electrical seals. With fewer connections, material cost is reduced, reliability is enhanced, and downtime is reduced.

Abstract: A composition comprising a magnesium halide coated macroporous carbonaceous substrate is provided for effecting moisture removal from a hydrogen halide fluid. Moisture removal is effected by intimately contacting the hydrogen halide fluid with the magnesium halide coated macroporous carbonaceous substrate and separating the fluid from the coated substrate.

Abstract: A composition comprising a magnesium halide coated macroporous carbonaceous substrate is provided for effecting moisture removal from a hydrogen halide fluid. Moisture removal is effected by intimately contacting the hydrogen halide fluid with the magnesium halide coated macroporous carbonaceous substrate and separating the fluid from the coated substrate.

Abstract: The mass flow controller of the present invention includes a sensor. This sensor is used to detect a mass flow within a gas line. Additionally, this sensor provides an output to an electronic control system coupled to the sensor. The electronic control system will determine an expected mass flow based on the output of the sensor. The electronic control system will adjust a control valve with a control signal to regulate a first gas flow through the control valve.

Abstract: A composition comprising a magnesium halide coated macroporous carbonaceous substrate is provided for effecting moisture removal from a hydrogen halide fluid. Moisture removal is effected by intimately contacting the hydrogen halide fluid with the magnesium halide coated macroporous carbonaceous substrate and separating the fluid from the coated substrate.

Abstract: A system and method for regulating the temperature of a sensor to reduce temperature gradients that form within the sensor. In one embodiment, the temperature gradients are reduced utilizing a temperature regulator with two controlled zones that surround a variable capacitance sensor. Measurements are made for the ambient temperature of at least one of the two temperature controlled zones, and the temperature differential between the two temperature controlled zones. The temperature regulator then adjusts the temperature of the two controlled zones based upon this differential in order to minimize the existing temperature gradient.

Abstract: A method for producing a filter element of a plurality of hollow fiber membranes made of perfluorinated thermoplastic polymer with a pot or seal made of perfluorinated thermoplastic polymer. A bundle of hollow fiber membranes is prepared with the fibers substantially aligned, with at least one end sealed. The sealed end is placed in a temporary recess made in a molten pool of perfluorinated thermoplastic potting material and held in the molten pool while potting material flows around and up the fibers to form a unified pot after cooling and solidification of the potting material.

Abstract: A system and method for integrating gas components that combines together, either in an in-line or modular fashion, at least two gas components used in a gas stick for flowing a gas from a first point to an end point. In one embodiment, the present invention can be used to combine a pressure transducer, a filter, and a display into a single unit that will reduce the gas stick size along the gas flow axis of the gas stick. The gas components can be integrated using VCR connections for an in-line use of the present invention. In the modular form, the present invention can use a number of different connections to connect the gas components vertically on a modular base block (i.e., stacked approximately perpendicular to the modular base block). Thus, the gas components will stack vertically with respect to the traditional horizontal gas flow path axis.

Abstract: Systems and methods for digitally controlling sensors. In one embodiment, a digital controller for a capacitance diaphragm gauge is embedded in a digital signal processor (DSP). The controller receives digitized input from a sensor AFE via a variable gain module, a zero offset module and an analog-to-digital converter. The controller automatically calibrates the received input by adjusting the variable gain and zero offset modules. The controller also monitors and adjusts a heater assembly to maintain an appropriate temperature at the sensor. The controller utilizes a kernel module that allocates processing resources to the various tasks of a gauge controller module. The kernel module repetitively executes iterations of a loop, wherein in each iteration, all of a set of high priority tasks are performed and one of a set of lower priority tasks are performed. The controller module thereby provides sensor measurement output at precisely periodic intervals, while performing ancillary functions as well.

Abstract: Fluid separation assembly that allows easy and fast change-out even in confined spaces, and also minimizes or eliminates leakage during change-out. A fluid separation unit having a housing containing separation means, the housing having an inlet and an outlet spaced from the inlet, each including a fitting for attachment of the housing to a manifold or other device allowing fluid communication through the separation means to a point of use is provided. The fittings are designed for quick connect/disconnect, and for minimal or no leakage. The fittings may be on opposite ends, with top and bottom fittings of different configurations, thereby ensuring proper installation of the assembly. The particular medium to be separated is not particularly limited, and can include slurries, fluids including water, and pre-loaded chromatography columns.