Abstract:
Metal precision weights (1) used primarily in laboratory conditions become polluted and contaminated on their surface during use, e.g. from the ambient air, from contact with hands, from water adsorption, and the like. These impurities (3) cause an increase in the mass of the weights (1) above the permitted tolerances, leading to the movement of the weights (1) to a lower class of accuracy and to the need to purchase new weights (1). According to the invention, the weight (1) is provided on its surface with a photocatalytic layer (2) which adsorbs the impurities, (3) and the contaminated weight (1) is then irradiated with electromagnetic radiation (9) having a wavelength from 0.2 nm to 1000 nm. During the subsequent photocatalytic reaction, the impurities (3) are converted into a gaseous phase (10) and are discharged from the surface of the weight (1 ) which thus returns to its initial nominal weight value.
Abstract:
A method of plasma treatment of an internal and/or external surface of a hollow electrically non-conductive body (1), the principle of which consists in that on the internal surface (2) of a hollow electrically non-conductive body (1) and/or on the external surface (3) of a hollow electrically non-conductive body (1) there acts a layer of electrical plasma of a surface dielectric barrier discharge generated in a volume (7, 9) of gas by alternating or pulse voltage (10) with an amplitude higher than 100 V from a pair of liquid electrodes formed by an internal electrically conductive liquid (4) situated inside the hollow electrically non-conductive body (1) and by an external electrically conductive liquid (5) situated outside the hollow electrically conductive body (1). The electrical plasma is generated above the surface (6, 8) of the electrically conductive liquid (4, 5), where in the volume (7, 9) of the gas, there forms a layer of electrical plasma forming a ring (11) copying the shape of the surface (2, 3) of the hollow electrically non-conductive body (1), wherein the electrical resistance between the liquid electrodes is greater than 10 kΩ. The invention also is a device for carrying out the aforementioned method of plasma treatment of the internal and/or external surface of a hollow electrically non-conductive body (1).
Abstract:
The method relates to triggering a self-propagating reduction-exfoliation process of graphene oxide in a porous material containing graphene oxide to increase the total electric conductivity and the specific surface area of the porous material. It's subject matter consists in that the initial electric plasma is generated in the adjacent part and only partly in the inside part (4) of the total volume (2) of the reduced-exfoliated porous material. This triggers the self-propagating reduction-exfoliation process, wherein to generate the initial electric plasma the parameters of the following group are fulfilled: the temperature of the working gas is less than 400°C, the pressure of the working gas is higher than 10 kPa, the speed of the working gas is less than 0,1 m×s-1, the temperature of the total volume of the porous material is less than 200°C.
Abstract:
The plasma modification of gases in large volumes, and the modification of powders and liquids at atmospheric pressure presents a considerable problem due to the specific properties of the plasma sources. For the decontamination of gases, a rotary type of gliding arc discharge is used, generated by a high voltage source (2) connected to an outer electrode (3) with a rotationally symmetrical discharge chamber (4) and to an inner conical electrode (5) arranged in isolation and rotatably inside the discharge chamber (4), wherein the discharge is blown from the discharge chamber (4) by a stream of working transport gas (13). The methods and the device according to present invention are also based on the generation of a rotary type of gliding arc discharge but advantageously without blowing by gas (13), only by rotating the inner electrode (5), which has a specific shape of discharge scroll (16) or discharge propeller (17), without any negative pressure difference.