Abstract: A method of preparing a mixture of ribonucleotides consisting in hydrolysis f yeast nucleic acid with pancreatic ribonuclease at a pH 4.5-5.5. Thereafter, separating the ribonucleotide fraction from the obtained hydrolyzate is effective on membranes with pores sized 50-150 .ANG. with subsequent purification and isolation of the end product.

Abstract: An apparatus for measuring hardness of materials has an indentor to be pressed into the surface of material, a rod in the form of a center plate having a shank rigidly secured to one end thereof and the indentor rigidly secured to the other end thereof. The apparatus also has a dynamometric gauge having a first branch thereof with a hole in which the shank of the rod is received. A second branch of the dynamometric gauge supports a spindle of a device for loading the indentor. One of the branches of the dynamometric gauge carries at least one pick-up for measuring the load at the indentor engageable with the other branch of the dynamometric gauge. The apparatus also has a device for measuring the depth of penetration of the indentor into the surface of material in the form of a frame having its opposed bars enclosing the first branch of the dynamometric gauge.

Abstract: A heat engine speed governor in which a differential mechanism has its input shaft operatively connected to a unidirectional electric motor, an input shaft connected to a heat engine and an output shaft connected to a fuel metering member of the heat engine. An electric motor speed control channel has a measuring means for measuring speed of the shaft connected to an input of a device for forming a control signal which has a master input connected to an output of a device for forming an electric motor speed control program. A means for measuring speed of the input shaft in a channel for correcting the electric motor speed in accordance with the heat engine speed is connected to a differentiating unit having an output connected to a correcting input of the device.

Abstract: The centrifuge has a drive rotating a rotor whose position relative to the vertical axis of the centrifuge is monitored by an unbalance sensor located on the installation plate which is accommodated in a recess of the ring in a plane perpendicular to the vertical axis. The ring is installed on the mounting surface of the drive casing with a provision for being moved and set relative to said surface so that the plane of the ring is constantly parallel with the lower surface of the rotor. The installation plate has a hollow for accommodating the unbalance sensor, the shape of the surface of said hollow being mutually complementary with the shape of the mounting surface of the drive casing and the installation plate is located in said ring with a provision for moving in said plane perpendicular to the vertical axis.

Abstract: The proposed machine comprises a chamber accommodating a headstock and a tailstock. The headstock has a rotation drive, whereas the tailstock is capable of longitudinal movement along a guide. The machine also includes a rod carrying a spray gun capable of lateral reciprocations by a drive in guides secured on the carriage capable of moving longitudinally by a drive along a guide. The tailstock has a hole, whereas a table of a size smaller than the dimensions of the hole is secured on the guide. A rear wall of the chamber has a longitudinal slot, the chamber having a gate capable of longitudinal displacement and engageable with a hollow pusher secured on the carriage and receiving the rod. The drives are arranged at the outer side of the rear wall of the chamber.

Abstract: An intrauterine device comprises a strip, a rod interconnected with the strip to form a T-shaped element therewith, a coil mounted on the rod, and a thread connected to the rod for dynamic monitoring of the IUD while in the uterine cavity. The coil has at least two layers, of which the first layer is made of an elastic polymer material, serves as a base, and faces directly the rod, while the second layer is made of metal.

Abstract: An apparatus for designing three-dimensional structures comprises a unit for recording linear coordinates having a movable support and guideways, crosspiece, carriage and vertical rod which are coupled to one another and which cause displacement along linear coordinates. Sensors of displacement along linear coordinates X, Y, Z are coupled to the guideways, crosspiece, carriage and vertical rod for causing displacement. The apparatus also has an angle joint having three series-connected angle arms for rotation with respect to X, Y, Z axes, respectively. Sensors for recording a change in an angular coordinate .phi., .phi..sub.1, .phi..sub.2, respectively, of rotation with respect to X, Y, Z axes, respectively, are coupled to the angle arms, the point of intersection of X, Y, Z axes of entered coordinates of the movable support coinciding with a point of intersection of X, Y, Z axes of the angle arms for rotation with respect to X, Y, Z axes, respectively.