Abstract: The present invention relates to a sinter powder (SP) comprising 59.5% to 99.85% by weight of at least one thermoplastic polyurethane (A), 0.05% to 0.5% by weight of at least one flow agent (B), 0.1% to 5% by weight of at least one organic additive (C), 0% to 5% by weight of at least one further additive (D) and 0% to 30% by weight of at least one reinforcer (E), based in each case on the sum total of the percentages by weight (A), (B), (C), (D) and (E). The present invention further relates to a method of producing a shaped body by sintering the sinter powder (SP), to a shaped body obtainable by the method of the invention, and to the use of at least one flow agent (B) and at least one organic additive (C) in a sinter powder (SP) to improve the flowability and coalescence of the sinter powder (SP). The present invention further relates to the use of the sinter powder (SP) in a sintering method, and to a method of producing the sinter powder (SP).

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A circuit for biasing a gallium arsenide (GaAs) power amplifier includes a reference voltage generator circuit implemented in a gallium arsenide (GaAs) material system, a field effect transistor (FET) bias circuit implemented in the gallium arsenide material system and adapted to receive an output of the reference voltage generator circuit and adapted to provide an output to a radio frequency (RF) amplifier stage.

Abstract: A method and apparatus for biasing an amplifying device whereby the bias current tracks the input power or the power level of a control signal to thereby efficiently match the bias current with needs of the amplifying device. This method and apparatus overcomes the drawbacks of the prior art by biasing, not for maximum output power, but for the power level of the input signal or the control signal. In one embodiment a current conditioner operates in connection with the self adjusting biasing circuit to scale or adjust, potentially on an exponential basis, the biasing current for one or more amplifier stages. A cancellation current source may be configured within the bias circuit to cancel unneeded current to further minimize current consumption.

Abstract: According to one exemplary embodiment, a circuit arrangement includes a power amplifier configured to receive an RF input signal. The circuit arrangement further includes a control circuit configured to receive and convert the RF input signal to an output DC voltage. The control circuit includes a voltage amplifier coupled to a peak detector circuit, where the peak detector circuit outputs the output DC voltage. The circuit arrangement further includes an analog control bias circuit coupling the output DC voltage to a bias input of the power amplifier. The output DC voltage causes the power amplifier to have a quiescent current that increases in a way that is substantially logarithmic with respect to the amplitude of the RF input signal. An increase in the RF input power can cause a substantially linear increase in the output DC voltage, where the RF input power is measured in dBm.

Abstract: A method and apparatus for biasing an amplifying device whereby the bias current tracks the input power or the power level of a control signal to thereby efficiently match the bias current with needs of the amplifying device. This method and apparatus overcomes the drawbacks of the prior art by biasing, not for maximum output power, but for the power level of the input signal or the control signal. In one embodiment a current conditioner operates in connection with the self adjusting biasing circuit to scale or adjust, potentially on an exponential basis, the biasing current for one or more amplifier stages. A cancellation current source may be configured within the bias circuit to cancel unneeded current to further minimize current consumption.

Abstract: According to one exemplary embodiment, a circuit arrangement includes a power amplifier configured to receive an RF input signal. The circuit arrangement further includes a control circuit configured to receive and convert the RF input signal to an output DC voltage. The control circuit includes a voltage amplifier coupled to a peak detector circuit, where the peak detector circuit outputs the output DC voltage. The circuit arrangement further includes an analog control bias circuit coupling the output DC voltage to a bias input of the power amplifier. The output DC voltage causes the power amplifier to have a quiescent current that increases in a way that is substantially logarithmic with respect to the amplitude of the RF input signal. An increase in the RF input power can cause a substantially linear increase in the output DC voltage, where the RF input power is measured in dBm.

Abstract: A high-isolation, low-power high-speed multiplexer circuit suitably includes a buffer stage and a current steering tree stage. By employing common select lines for both stages of the circuit, both the input buffer and the deselected channel provide cumulative isolation for the deselected channels.

Abstract: There is disclosed herein an automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking to the location of solid or very viscous samples. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pump of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration.

Abstract: There is disclosed a sample preparation chamber for a system for preparing samples of various compositions for assay by liquid chromatography. The sample preparation chamber is includes a container having a threaded cap and a threaded, lightweight, translucent plastic cup. A stirrer/grinder shaft driven by a motor and connected to a propeller/grinder passes through the cap. The cup has a sloped bottom with a sump region, and a fill/empty pipe passes through the cap and has its outlet at or near the sump. A nozzle/fill pipe arrangement allows the walls to be washed down as liquid is pumped into the cup. A second fill pipe with its outlet spaced up from the bottom of the cup is also used, and a sample metering valve having an inlet in said cup is present.

Abstract: An automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking solid or very viscous samples to the sample preparation system. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pumping of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration.

Abstract: An automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking solid or very viscous samples to the sample preparation system. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pumping of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration.

Abstract: A sample metering valve for both liquid samples and slurry samples with entrained gas bubbles. The sample metering valve for liquids is comprised of a piston with sample chambers formed in the side thereof said piston moving freely into and out of a cylinder having an aperture matching the size of the piston. Sealing is provided by a seal which has no dead volume which cold flows under a spring bias to maintain the seal under various operating conditions. The sample metering valve for slurry samples includes a syringe embodiment having separately moving piston and valve in a cylinder. The syringe valve sucks up sample with a piston, isolates the sample with the valve and compresses the entrained gas bubbles with the piston. Another embodiment uses three, three way valves which are coupled to a pump and a means to compress the sample.

Abstract: An automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking solid or very viscous samples to the sample preparation system. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogenous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cap to allow pumping of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a know volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration.

Abstract: A sample metering valve for both liquid samples and slurry samples with entrained gas bubbles. The sample metering valve for liquids is comprised of a piston with sample chambers formed in the side thereof said piston moving freely into and out of a cylinder having an aperture matching the size of the piston. Sealing is provided by a seal which has no dead volume which cold flows under a spring bias to maintain the seal under various operating conditions. The sample metering valve for slurry samples includes a syringe embodiment having separately moving piston and valve in a cylinder. The syringe valve sucks up sample with a piston, isolates the sample with the valve and compresses the entrained gas bubbles with the piston. Another embodiment uses three, three way valves which are coupled to a pump and a means to compress the sample.

Abstract: A sample metering valve for both liquid samples and slurry samples with entrained gas bubbles. The sample metering valve for liquids is comprised of a piston with sample chambers formed in the side thereof said piston moving freely into and out of a cylinder having an aperture matching the size of the piston. Sealing is provided by a seal which has no dead volume which cold flows under a spring bias to maintain the seal under various operating conditions. The sample metering valve for slurry samples includes a syringe embodiment having separately moving piston and valve in a cylinder. The syringe valve sucks up sample with a piston, isolates the sample with the valve and compresses the entrained gas bubbles with the piston. Another embodiment uses three, three way valves which are coupled to a pump and a means to compress the sample.