SU476873A1 - Device for laboratory testing of biological substrates in heat exchange medium - Google Patents

Description

one

The invention relates to the design of laboratory devices for the examination of sperm of farm animals during deep freezing, which can be used at central and local artificial insemination stations to find the optimal freezing and thawing regimes of sperm manufacturers.

A device for freezing semen of farm animals is known, comprising a Dewar vessel, an evaporator, a cooler connected by a pipeline, and a measuring device.

In order to determine the optimal freezing and thawing of the seed in the proposed device, the cooler is made in the form of a sectional chamber, the sections of which are formed by corrugated plates installed parallel to each other, the plates of each section being located at different distances from each other and connected to the measuring device.

The drawing shows the proposed device, the overall appearance.

The device consists of a cooler 1, made in the form of a sectional chamber, the sections of which are formed by corrugated plates 2, a Dewar 3, an evaporator 4 and a measuring device 5. In each section 6

temperature sensors 7 are located associated with the meter.

The device works as follows.

Before freezing, the biological substrate is diluted sperm, pre-cooled to 2-5 ° C. poured into the cooler between sections. Under the action of heat coming from the electric heater, part of the liquefied gas evaporates, creating an overpressure in the Dewar vessel.

Under pressure, the liquefied gas is displaced into the evaporator, where it turns into a gaseous state, after which it enters section 6. After taking away from the cooler and the sperm, in the section, heat, the gas heats up and goes to the atmosphere. In the Dewar vessel, the pressure increases gradually. The higher the pressure, the more liquified gas is displaced into the evaporator and the faster the space in the cooler is cooled. Regulating the pressure in the Dewar vessel, thereby regulating the temperature of the freezing of sperm for each section, and at a constant pressure of liquid nitrogen vapor in the system, due to the difference in volume of the sections, freezing of the sperm occurs in different modes and at different speeds, which is recorded by sensors 7 The signals from which are sent to the local supply bay 5. After all sections have a temperature of minus 80-120 ° C, liquid nitrogen is fed into the system to bring the temperature of the object to be frozen to minus 196 ° C. The defrosting process is carried out as follows. Heated water is fed to section 6. After part of the heat is given to the space of the cooler and the sperm frozen in the sections, the cooled water flows outside into any collecting vessel or sewage system. In this way, various conditions are created for defrosting sperm, and the actual temperatures that are obtained are recorded by measuring device 5. Thus, this device determines which optimal volume is necessary to freeze one or another biological substrate with a high yield of viable cells and what defrosting mode is required for this. and, moreover, the selection of the liquid phase that occurs during defrosting, taking into account the exact temperatures, makes it possible to investigate the kinetics of changes in activity and vaemosti sperm depending on the mode defrosting. The subject of the invention is a device for the laboratory investigation of biological substrates in a heat exchange medium, for example, seed of farm animals, including a Dewar vessel, an evaporator, a cooler, connected by a pipeline and a measuring device, which is designed to determine the optimal freezing and thawing of the seed, the cooler made in the form of a sectional chamber, the sections of which are formed by corrugated plates installed in parallel, with the plates of each section being located each other t pa other different distances.

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