Abstract: A metal heat exchanger tube for the evaporation of liquids on the outside of the tube, having a tube axis, a tube wall, and integrally formed ribs that run circumferentially on the outside of the tube. The ribs have a rib foot, rib flanks, and a rib tip, wherein the rib foot projects substantially radially from the tube wall. A respective groove is located between every two ribs that are adjacent to one another in the axial direction. At least first, second, and third lateral material projections, which are formed from the material of the ribs, are arranged on a first, second, and third level on the rib flanks in such a way that the grooves are largely covered by all of the material projections. The first, second, and third lateral material projections are formed on levels that are in each case differently spaced apart from the tube wall in the radial direction.

Abstract: A metal heat exchanger tube for the evaporation of liquids on the outside of the tube, having a tube axis, a tube wall, and integrally formed ribs that run circumferentially on the outside of the tube. The ribs have a rib foot, rib flanks, and a rib tip, wherein the rib foot projects substantially radially from the tube wall. A respective groove is located between every two ribs that are adjacent to one another in the axial direction. At least first, second, and third lateral material projections, which are formed from the material of the ribs, are arranged on a first, second, and third level on the rib flanks in such a way that the grooves are largely covered by all of the material projections. The first, second, and third lateral material projections are formed on levels that are in each case differently spaced apart from the tube wall in the radial direction.

Abstract: A metal heat exchanger tube for the evaporation of liquids on the outside of the tube, having a tube axis, a tube wall, and integrally formed ribs that run circumferentially on the outside of the tube. The ribs have a rib foot, rib flanks, and a rib tip, wherein the rib foot projects substantially radially from the tube wall. A respective groove is located between every two ribs that are adjacent to one another in the axial direction. At least first, second, and third lateral material projections, which are formed from the material of the ribs, are arranged on a first, second, and third level on the rib flanks in such a way that the grooves are largely covered by all of the material projections. The first, second, and third lateral material projections are formed on levels that are in each case differently spaced apart from the tube wall in the radial direction.

Abstract: The invention relates to a metal heat exchanger tube for the evaporation of liquids on the outside of the tube, comprising a tube axis, a tube wall, and integrally formed ribs that run circumferentially on the outside of the tube. The ribs have a rib foot, rib flanks, and a rib tip, wherein the rib foot projects substantially radially from the tube wall. A respective groove is located between every two ribs that are adjacent to one another in the axial direction. At least first, second, and third lateral material projections, which are formed from the material of the ribs, are arranged on a first, second, and third level on the rib flanks in such a way that the grooves are largely covered by all of the material projections. According to the invention, the first, second, and third lateral material projections are formed on levels that are in each case differently spaced apart from the tube wall in the radial direction.

Abstract: The invention relates to a heat exchanger tube with at least one structured region on the inside of the tube, which has the following features: a) integral internal ribs of height H run on the inside of the tube in axially parallel or helical-line-shaped manner continuously over the circumference at an angle of inclination ?1, measured with respect to the tube axis, with primary grooves being formed, b) the internal ribs are crossed over the entire circumference of the tube by spaced-apart secondary grooves which, parallel to one another at an angle of inclination ?2, measured with respect to the tube axis, have a notch depth T2 and a groove opening angle ?2, c) the internal ribs and the secondary grooves are crossed over the entire circumference of the tube by spaced-apart tertiary grooves which run continuously over the circumference parallel to one another at an angle of inclination ?3, measured with respect to the tube axis, and have a notch depth T3 and a groove opening angle ?3.

Abstract: An optical irradiation device for the polarization of alkali metal atoms for the hyperpolarization of noble gases by spin exchange includes at least one semiconductor laser device which can generate laser light which, with regard to its wavelength, is suitable for the polarization of the alkali metal atoms. A polarizer effects circular polarization of the laser light generated by the semiconductor laser device. A device for introducing the laser light into a working region in which the alkali metal atoms to be polarized can be present, and a device for defining a wavelength of the laser light, which can couple part of the laser light back into the semiconductor laser device in order thereby to define the wavelength of the laser light at a predetermined wavelength or a predetermined wavelength range.

Abstract: An optical irradiation device for the polarization of alkali metal atoms for the hyperpolarization of noble gases by spin exchange includes at least one semiconductor laser device which can generate laser light which, with regard to its wavelength, is suitable for the polarization of the alkali metal atoms. A polarizer effects circular polarization of the laser light generated by the semiconductor laser device. A device for introducing the laser light into a working region in which the alkali metal atoms to be polarized can be present, and a device for defining a wavelength of the laser light, which can couple part of the laser light back into the semiconductor laser device in order thereby to define the wavelength of the laser light at a predetermined wavelength or a predetermined wavelength range.

Abstract: The invention relates to a heat exchanger tube with at least one structured region on the inside of the tube, which has the following features: a) integral internal ribs of height H run on the inside of the tube in axially parallel or helical-line-shaped manner continuously over the circumference at an angle of inclination ?1, measured with respect to the tube axis, with primary grooves being formed, b) the internal ribs are crossed over the entire circumference of the tube by spaced-apart secondary grooves which, parallel to one another at an angle of inclination ?2, measured with respect to the tube axis, have a notch depth T2 and a groove opening angle ?2, c) the internal ribs and the secondary grooves are crossed over the entire circumference of the tube by spaced-apart tertiary grooves which run continuously over the circumference parallel to one another at an angle of inclination ?3, measured with respect to the tube axis, and have a notch depth T3 and a groove opening angle ?3.