Abstract: Raman scattering, while a powerful and versatile technique, relies of the detection of weak signals. Detecting the signal can be difficult if there is interference, especially if the interference comes from scattered stray light of the laser used to generate the Raman signal. Described here is a frequency modulation technique in combination with heterodyne detection that simultaneously rejects interference from ambient light as well as from scattered stray laser light. This provides a means to detect Raman signal and discriminate against scattered light without using an expensive and bulky spectrometer.

Abstract: Raman scattering, while a powerful and versatile technique, relies of the detection of weak signals. Detecting the signal can be difficult if there is interference, especially if the interference comes from scattered stray light of the laser used to generate the Raman signal. Described here is a frequency modulation technique in combination with heterodyne detection that simultaneously rejects interference from ambient light as well as from scattered stray laser light. This provides a means to detect Raman signal and discriminate against scattered light without using an expensive and bulky spectrometer.

Abstract: A Raman analyzer for analyzing light emitted from a Raman cell is provided that has a beam splitter configured to split the light emitted from the Raman cell into a first beam and a second beam. An atomic vapor filter can be used to filter a Raman scattered line from the first beam and a chopper system can periodically interrupt the first and second beams that are directed towards a photo detector, which can convert light from the first and second beams into an electrical signal. The signal output from the photo detector can optionally be amplified, digitized, Fourier filtered, and/or subjected to Fourier analysis.

Abstract: A Raman analyzer for analyzing light emitted from a Raman cell is provided that has a beam splitter configured to split the light emitted from the Raman cell into a first beam and a second beam. An atomic vapor filter can be used to filter a Raman scattered line from the first beam and a chopper system can periodically interrupt the first and second beams that are directed towards a photo detector, which can convert light from the first and second beams into an electrical signal. The signal output from the photo detector can optionally be amplified, digitized, Fourier filtered, and/or subjected to Fourier analysis.

Abstract: A Raman head is provided capable of operating at high surrounding pressures. The Raman head has housing having a first, sealed chamber filled with an incompressible liquid and a second chamber that is open to the surrounding environment. At least one bellows can be used to equalize pressure between the first sealed chamber and the surrounding environment. A planar side of a pair of plano-concave lens is positioned within the first chamber and the concave side of each plano-concave lens is positioned within the second chamber of the Raman head. Light emitted as a result of a laser beam in communication with the pair of plano-concave lens can be analyzed by a Raman analyzer.

Abstract: A compact, ultra-sensitive, inexpensive NIR spontaneous Raman spectrometer is presented. High sensitivity is achieved by the use of a multi-pass cell configuration combined with the electromotive properties of silicon crystal surface. A thin layer of silicon oxide chemisorbs molecules, which stick to its surface without altering their spectroscopic signatures. This new Raman spectrometer may be used to detect less than 40 ng (?0.5 n mol) of ammonium nitrate deposited on the silicon surface with the signal-to-noise ratio better than 50 during 0.1 s recording time and for an illuminated area of 2×10?8 m2. These results may be useful in many areas, for example the foundation of an extended project to record the dissolved NO3? ions in a large river such as the Mississippi.

Abstract: A fuel pump according to the invention includes a housing and a part, which is a moving part during operation and which bears on a housing region at least indirectly. It is proposed that the fuel pump includes a coating which is applied to the housing region on a side of the housing region which faces towards the moving part, and that the coating is composed of a plastic.

Abstract: A compact, ultra-sensitive, inexpensive NIR spontaneous Raman spectrometer is presented. High sensitivity is achieved by the use of a multi-pass cell configuration combined with the electromotive properties of silicon crystal surface. A thin layer of silicon oxide chemisorbs molecules, which stick to its surface without altering their spectroscopic signatures. This new Raman spectrometer may be used to detect less than 40 ng (?0.5 n mol) of ammonium nitrate deposited on the silicon surface with the signal-to-noise ratio better than 50 during 0.1 s recording time and for an illuminated area of 2x10?8 m2. These results may be useful in many areas, for example the foundation of an extended project to record the dissolved NO3? ions in a large river such as the Mississippi.

Abstract: A Raman head is provided capable of operating at high surrounding pressures. The Raman head has housing having a first, sealed chamber filled with an incompressible liquid and a second chamber that is open to the surrounding environment. At least one bellows can be used to equalize pressure between the first sealed chamber and the surrounding environment. A planar side of a pair of plano-concave lens is positioned within the first chamber and the concave side of each plano-concave lens is positioned within the second chamber of the Raman head. Light emitted as a result of a laser beam in communication with the pair of plano-concave lens can be analyzed by a Raman analyzer.

Abstract: A Raman analyzer for analyzing light emitted from a Raman cell is provided that has a beam splitter configured to split the light emitted from the Raman cell into a first beam and a second beam. An atomic vapor filter can be used to filter a Raman scattered line from the first beam and a chopper system can periodically interrupt the first and second beams that are directed towards a photo detector, which can convert light from the first and second beams into an electrical signal. The signal output from the photo detector can optionally be amplified, digitized, Fourier filtered, and/or subjected to Fourier analysis.

Abstract: A fuel pump according to the invention includes a housing and a part, which is a moving part during operation and which bears on a housing region at least indirectly. It is proposed that the fuel pump includes a coating which is applied to the housing region on a side of the housing region which faces towards the moving part, and that the coating is composed of a plastic.

Abstract: A fuel injection valve for internal combustion engines having a valve body in which a bore is embodied, a valve seat face, at least one injection opening embodied on the end toward the combustion chamber of the bore, and at least one injection opening connecting the bore with the combustion chamber of the engine. A nozzle needle is longitudinally displaceably guided in the bore and on its end toward the combustion chamber it has a sealing face, which cooperates with the valve seat face and thus controls the at least one injection opening. The nozzle needle has a central longitudinal bore, in which an inner needle is disposed that is fixed immovably relative to the valve body. The nozzle needle is guided over at least part of its length on the inner needle, so that the nozzle needle is kept exactly centrally in the bore at all times.

Abstract: A fuel injection valve for internal combustion engines, having a valve body (3) in which a bore (7) is embodied. A valve seat face (10) and at least one injection opening (9) are embodied on the end toward the combustion chamber of the bore (7), and at least one injection opening (9) connects the bore (7) with the combustion chamber of the engine. A nozzle needle (12) is longitudinally displaceably guided in the bore (7) and on its end toward the combustion chamber it has a sealing face (217), which cooperates with the valve seat face (10) and thus controls the at least one injection opening (9). The nozzle needle (12) has a central longitudinal bore (19), in which an inner needle (14) is disposed that is fixed immovably relative to the valve body (3). The nozzle needle (12) is guided over at least part of its length on the inner needle (14), so that the nozzle needle (12) is kept exactly centrally in the bore (7) at all times (FIG. 1).

Abstract: An electric power tool, in particular a right-angle grinder is disclosed, having an elongated motor housing in which an electric motor is received, having a gear drive housing at a first end of the motor housing to receive a gear drive for driving a working spindle, having a handle element which is fastened rotatably at a second end of the motor housing and in which a grip switch is arranged, and having air intake slots to cool the electric motor which are arranged at the second end of the motor housing. In addition, at least one baffle plate, which serves to deflect particles and can simultaneously be configured as a cooling panel for cooling electronic components, is preferably located in the flow region of the air intake slots.

Abstract: A power tool is disclosed, having an elongated motor housing in which an electric motor is received, having a gear drive housing at a first end of the motor housing to receive a gear drive for driving a working spindle, and having a handle element which is fastened rotatably at a second end of the motor housing and in which a grip switch is arranged. The handle element is rotatable with respect to the motor housing into at least four predefined angular positions that are preferably offset from one another by angles of 90°, and can be snap-locked in them.

Abstract: A motor-driven machine with variable torque setting includes a motor, a planetary gearing driving a work spindle and a rotatably mounted internal gear actuating a motor de-energizer against the action of a spring force when a settable limit torque is exceeded. To achieve a compact design, a torsion spring element extending in the axial direction alongside the planetary gearing is provided for generating the spring force. The torsion spring element carries a swivel element at one end which engages a cam on the internal gear and is held at an opposite end in a support so that the swivel element can swivel out of an initial position against the action of the force of the torsion spring element to de-energize the motor.

Abstract: An electric tool with a source of power that is independent of the line and with a transmission housing or motor housing that is also designed to function as a grip, with another grip merging into one side of it. To position the center of gravity such that the tool will be easier to handle and to allow the operator to continue working when one battery pack goes dead, attachments for battery packs are provided at the end of each grip.

Abstract: In motor-operated machines, especially portable electric tools, it is essential to prevent an impermissibly high torque on the driveshaft or operating spindle. This is attained by means of a torque-disengagement mechanism. An especially elegant, compact, precisely responsive torque-disengagement mechanism is attained by mounting one of the two bearings for a driveshaft in the machine housing or similar structure in such a way that it can move across the longitudinal axis or radially far enough to initiate a switching procedure. The bearing is secured in an initial position by means of an opposing force. The position represents both the zero position for the switching procedure and the correct position of the axis of the driveshaft during operation. If the machine includes a means of varying the torque, the power of the opposing force can be adjusted and maintained either continuously or discontinuously.

Abstract: A power-screwdriver device with variable torque adjustment consists essentially of a drive mechanism, transmission, and cutoff mechanism. In order to provide a power screwdriver that is strong and inexpensive and in which the torque can be controlled with no need for a torque clutch, there is a bearing site on a transmission shaft. The bearing allows the shaft to move radially. There is a sensor that emits a motor-cutoff signal when the shaft does move radially. The radial deviation is employed as a measure of torque. The measure is adjusted with an adjusting device.

Abstract: In an exemplary embodiment, radiography and fluoroscopy is carried out by a film cassette, an image intensifier television chain and a circuit for the automatic influencing of parameters determining the x-ray image quality, which circuit exhibits a radiation sensor, and a comparator for the comparison of a nominal setpoint value with the actual value delivered by the sensor, in which analog to digital converters are provided for the formation of an electric signal corresponding to the electrode voltages of the x-ray image intensifier, which electric signal is supplied in the form of an address to a memory in which the dependency of the conversion factor of the x-ray image intensifier upon the electrode voltage is stored.