摘要:
Elastomers based on acrylates, which are comprised, in the amount of at least 40 wt. % and as much as 100 wt. %, of one or more copolymers having a molecular weight>50,000 daltons and comprised of units of:i) acrylate monomers in the amount of 50-95 wt. %, andii) macromonomers comprised of a vinylic group and, covalently bonded with such group, a polyvinyl unit selected from the group of acrylates and methacrylates and having a glass transition temperature Tg at least 60.degree. C. and molecular weight 500-100,000 dalton.
摘要:
Copolymers, adaptable for use as molding compositions for optically readable data storage media, said copolymers being free of aromatic groups and comprising;(A) 5 to 95 percent by weight of at least one ester of the formula ##STR1## wherein R.sub.1 is an unsubstituted or alkyl substituted alicycle having from 5 to 19 carbon atoms, a homopolymer of such an ester having a Vicat softening temperature above 80.degree. C.;(B) 90 to 5 percent by weight of at least one ester of the formula ##STR2## wherein R.sub.2 is hydrogen or methyl and R.sub.3 is a linear or branched aliphatic group having from 2 to 22 carbon atoms, a homopolymer of such an ester having a Vicat softening temperature below 90.degree. C.;(C) 0 to 50 percent by weight of methyl methacrylate; and(D) 0 to 20 percent by weight of an oprotic monomer having a polar group.
摘要:
An apparatus for measuring liquid level in a container, particularly the fuel tank of a motor vehicle, has a plurality of detector stages for sensing or detecting a plurality of liquid level ranges, whereby an indicator stage can be arranged to indicate a first, normal range of measurement, and a second, precise resolution can be obtained of at least a portion of the overall measurement range, without requiring an excessively larger indicator stage. This is accomplished by arranging at least two groups of sensing elements one above the other in the tank and connecting them to indicator elements via change-over circuits such that one range of measurement is made via one group of sensing elements and a second, more precise range of measurements is made via a second group of sensing elements.
摘要:
A device for the electric monitoring of the level of a liquid contained in a container, comprising at least one temperaturedependent resistance sensor immersed in the liquid the level of which is to be monitored, a constant current source being connectable to the resistance sensor under the control of a program control device controlling a device for detecting and storing the initial voltage drop on the resistance sensor at an initial time and the measurement voltage at a specified time after connection of the constant current source, and a device for evaluating the voltages by subtracting the measurement voltage from the initial voltage and under the circumstances inverting the difference to form a display voltage which corresponds to the level of the liquid. Several of these resistance sensors are arranged at different levels within the container, the sensors being connectable one after the other, controlled by the program control device, to the constant current source and to the device for evaluating the voltage drop on them. A fixed-value storage provides a supply of fixed-value voltages one of which respectively is selectably dependent on the respective resistance sensor active at the time, and an adder is appliable in order to form the display voltage, with the evaluated voltage which is analog to the depth of immersion of the active resistance sensor and with the fixed-value voltage which corresponds to the height of that resistance sensor.
摘要:
Products based on polymethylmethacrylate (PMMA) so resistant to yellowing and so highly transparent that even the edges of plates produced from this material have a neutral colour, i.e. do not display any yellow tone. This effect is obtained by the admixture of 5 to 50 ppm inorganic, reducing phosphorus compounds after polymerisation. This enables the brightener content to be reduced under 10 ppb, and so the end product may also be used in contact with foodstuffs.
摘要:
A flow meter includes a rotor housing having an inlet, an outlet, and a bore extending axially through the housing from the inlet to the outlet, and a screw spindle arrangement including at least two rotary helical worm bodies which are disposed in the bore and which engage in a form fit manner within one another. A pulse generator is mounted on one of the worm bodies and triggers electrical pulses in the mating measuring transducer which are dependent upon the rotational speed of the worm body. The measuring transducer has a pulse-adjusting and pulse-shaping stage which adjusts the magnitude and/or frequency of the pulses relative to a volumetric flow rate of fuel to the bore. An electric counting mechanism receives the electric pulses from the pulse-adjusting and pulse-shaping stage and typically transmits these pulses to a display unit for display.
摘要:
Elastomers based on acrylates, which are comprised, in the amount of at least 40 wt. % and as much as 100 wt. %, of one or more copolymers having a molecular weight >50,000 daltons and comprised of units of:i) acrylate monomers in the amount of 50-95 wt. %, andii) macromonomers comprised of a vinylic group and, covalently bonded with such group, a polyvinyl unit selected from the group of acrylates and methacrylates and having a glass transition temperature Tg at least 60.degree. C. and molecular weight 500-100,000 dalton.
摘要:
A step motor which, in addition to an exciter system for step-by-step movement, is provided with a further exciter system. As a result of the direct or indirect influence of the magnetic field generated by the secondary exciter system on the rotor which is supported so as to be able to move in an axial direction with respect to the stator, the rotor can be induced to move in a direction perpendicular to its step-by-step rotary motion, as well. Both exciter systems can be energized independently of one another, so that step-by-step rotary movement can be performed at any axial position of the rotor, and the rotor can be made to move in an axial direction during its rotary movement, as well as when it is at rest.