Abstract: A calibration module and methods for a time-of-flight ranging system. The calibration module may be built into the circuitry of the time-of-flight ranging system and allows various operating parameters to be measured and evaluated. The calibration modes include amplitude calibration, frequency calibration, and time delay calibration. The calibration mode also includes an electronic noise measurement mode. The calibration modes may be initiated on power-up or reset, or in response to user input or time-based trigger.

Abstract: A current limiter circuit which exhibits a low dropout voltage. The current limiter circuit is suitable for protecting process control equipment operating on a current loop. The current limiter circuit includes an interface for coupling to the current loop, and a current source element coupled to the process control equipment. The current source element comprises a current limiter circuit to limit the current flowing to the process control equipment, and a voltage reference circuit coupled to the current limiter circuit provides a predetermined voltage reference during operation of the current source element.

Abstract: A current loop control circuit for a process variable transmitter coupled to a receiver at a remote location through a two-conductor current loop. The current loop control circuit efficiently utilizes the current in the loop to produce an optimal voltage and current for the operation of the process variable measurement transmitter.

Abstract: A universal switching power supply for generating one or more output voltage levels wherein the power supply is operable over a range of AC and DC input supply voltages. The universal switching power supply achieves a ratio between the highest voltage and lowest voltage of at least 27. The universal switching power supply also features an intrinsically safe output. The intrinsically safe output circuitry comprises a multi-layer PCB with a planar core transformer.

Abstract: An envelope detector for detecting the envelope of an input signal. The envelope detector includes an inverter for inverting the input signal and two offsetting circuits for offsetting the input signal and the inverted input signal so as to align the peaks of the signals with zero volts. The two offset signals are then summed, which results in a signal proportional to the inverted envelope of the input signal.

Abstract: An electronic power management system includes at least one power distribution unit, a control panel, and at least one data bus. The power distribution unit distributes electrical power to at least one electric load and provides status of each electrical load and characteristics of the electrical power. The control panel receives the status and electrical power characteristics and controls operation of the electrical loads in response to the status and electrical power characteristics. The data bus communicatively couples the control panel and the power distribution units. The electrical characteristics for each load include measured electric current and voltage values, and an indication as to whether measured values are over, under, within a range, or out of a range of threshold values.

Abstract: An envelope detector for detecting the envelope of an input signal. The envelope detector includes an inverter for inverting the input signal and two offsetting circuits for offsetting the input signal and the inverted input signal so as to align the peaks of the signals with zero volts. The two offset signals are then summed, which results in a signal proportional to the inverted envelope of the input signal.

Abstract: A universal switching power supply for generating one or more output voltage levels wherein the power supply is operable over a range of AC and DC input supply voltages. The universal switching power supply achieves a ratio between the highest voltage and lowest voltage of at least 27. The universal switching power supply also features an intrinsically safe output. The intrinsically safe output circuitry comprises a multi-layer PCB with a planar core transformer.

Abstract: Compounds containing a primary amino group are converted into compounds containing a fluorine atom in place of the amino group by reaction of the amino compound with hydrogen fluoride and a nitrosating reagent under the influence of ultrasound or microwaves.

Abstract: An electronic relay for use with an ultrasonic transducer. The electronic relay selectively couples the ultrasonic transducer to an electronic circuit. The transducer includes an input/output port for receiving excitation signals from the circuit and for transmitting echo signals back to the circuit. The electronic relay comprises a solid state switch and a leakage control circuit. The solid state switch is connected between the transducer and the electronic circuit. The switch is responsive to an actuation signal from the circuit for opening and closing the switch. The leakage control circuit is coupled to the switch and functions to control leakage current when the switch is open so as to electrically isolate the transducer from the electronic control circuit.

Abstract: The present invention relates to a composition which can be used as reduction catalyst.This composition is characterized in that it comprises a support whose constituent material comprises at least one oxide chosen from oxides which are inert or capable of being made inert relative to the reaction mixture and a phase at least partially covering the said support, of which at least part comprises an intermetallic ruthenium-tin compound of composition Ru.sub.3 Sn.sub.7. The invention also describes the use of the reduction catalyst and its application to organic synthesis.

Abstract: The present invention relates to a process for the preparation of terpenic ketones, which comprises reacting a 1,3-butadiene derivative with a .beta.-keto ester followed by decarbalkoxylation of the product.

Abstract: The instant invention relates to a process for the preparation of fluoroanilines of formula (I) wherein a fluorinated nitrated benzene compound of formula (II) is subjected to a catalytic hydrogenation in a liquid medium containing a catalyst, under hydrogen pressure, carrying out a catalytic reduction reaction and, optionally, a hydrogenolysis reaction, wherein the compound of formula (II) is introduced gradually into the said medium so that the content of compound of formula (II) in the liquid remains less than or equal to 1000 ppm by mass, in order selectively to form the compound of formula (I).

Abstract: Substituted aromatic hydrocarbons, e.g. 1,3-difluorobenzene, are produced by dediazoniation of the corresponding aromatic primary amines by converting them into a corresponding diazonium salt in the presence of hypophosphorous acid and a metal catalyst so that the diazonium group is replaced by hydrogen as it is formed.

Abstract: The present invention relates to a process and a catalyst for hydrogenation of aromatic nitro or nitroso (nitrosated) compounds. The process, useful in hydrogenation, especially in the liquid phase, of compounds, nitroaromatic ones in particular, is defined in that the said compound is hydrogenated in the presence of tungsten carbide, the partial pressure of hydrogen being at least equal to two atmospheres (2.times.10.sup.5 pascals). The process also has application to organic synthesis.

Abstract: Terpene derivatives of formula I, their preparation and their use. In formula I, R represents a hydrogen atom or an alkanoyl radical and R' represents a hydrogen atom or an aliphatic hydrocarbon radical.

Abstract: Terpene derivatives of formula I, their preparation and their use. In formula I, R represents a hydrogen atom or an alkanoyl radical and R' represents a hydrogen atom or an aliphatic hydrocarbon radical.

Abstract: A process for the preparation of citral by the cracking of prenal diprenyl acetal in a vapor phase in the presence of a heterogeneous type of acid catalyst.

Abstract: The pressure regulator comprises a valve with a slide member (5) whose displacements are controlled by the pressure prevailing in the control chamber (7). This pressure is adjusted by an obturator (11) of tubular shape which, in its upper position, places the chamber (7) in communication with the opening (4) of the fluid outlet. The fluid is admitted into the valve by an opening (2) and the displacements of slide member (5) permit adjusting the pressure in the opening (3) which supplies a user. The control chamber (7) is fed from the opening (3) through a conduit (20) with fluid whose pressure is already adjusted.

Abstract: A process for converting tertiary amine N-oxides to aldehydes by reacting tertiary amine N-oxides in the presence of a catalytic quantity of a vanadium containing compound.