Abstract: A barrier fabric with a nano-fibrous layer for mechanical retention of organic substances formed by a sandwich structure containing a basic material from unwoven fabric of “spunbond” type with areal weight of 15 to 50 g/m2 to which at least one nano-fibrous layer is arranged, selected from hydrophilic polymer, a hydrophobic polymer, or in the case of double-layer arrangement, a combination of the hydrophilic polymer in one layer and the hydrophobic polymer in the other layer. The nano-fibrous layer is equipped with a protective covering layer, and the individual layers of the sandwich are connected to each other. The nano-fibrous layer has an organic polymer material with areal weight of 0.05 to 0.3 g/m2 and thickness from 90 to 150 nm. The covering layer is selected from an unwoven fabric of “spunbond” type, “meltblown” type, cotton textile and/or a mixture of cotton and polyester.

Abstract: A barrier fabric with a nano-fibrous layer for mechanical retention of organic substances formed by a sandwich structure containing a basic material from unwoven fabric of “spunbond” type with areal weight of 15 to 50 g/m2 to which at least one nano-fibrous layer is arranged, selected from hydrophilic polymer, a hydrophobic polymer, or in the case of double-layer arrangement, a combination of the hydrophilic polymer in one layer and the hydrophobic polymer in the other layer. The nano-fibrous layer is equipped with a protective covering layer, and the individual layers of the sandwich are connected to each other. The nano-fibrous layer has an organic polymer material with areal weight of 0.05 to 0.3 g/m2 and thickness from 90 to 150 nm. The covering layer is selected from an unwoven fabric of “spunbond” type, “meltblown” type, cotton textile and/or a mixture of cotton and polyester.

Abstract: A barrier fabric with a nano-fibrous layer for mechanical retention of organic substances, wherein it is formed by a sandwich structure containing a basic material from unwoven fabric of “spunbond” type with areal weight of 15 to 50 g/m2 to which at least one nano-fibrous layer is arranged, selected from the group comprising a hydrophilic polymer, a hydrophobic polymer, or in the case of double-layer arrangement, a combination of the hydrophilic polymer in one layer and the hydrophobic polymer in the other layer, and where the nano-fibrous layer is equipped with a protective covering layer, and where the individual layers of the sandwich are connected to each other, and where the nano-fibrous layer used as a barrier against penetration of allergens produced by the dust mites through the upholstery material of mattresses, pillows, bedclothes or soft furnishings, is created by an organic polymer material with areal weight of 0.05 to 0.

Abstract: Column for liquid chromatography contains a glass tube for sorbent packing closed with simple column seals and inserted into a jacket made of metal or plastic material. The jacket transfers axial forces exerted on the column seals by liquid pressure action by means of sockets. It secures the tightness of the column, enables the connection of the column to a chromatographic system, and has a protective function at the same time. The columns can be coupled in series by means of doubled sockets.

Abstract: The invention pertains to the sealing of pistons for pressurizing, pumping and displacing aggressive liquids and organic solvents. The design includes the sealing head proper and its attachment to the piston. Owing to its shape and material it is made of, the sealing head ensures a variable sealing thrust proportional to the pressure acting on the piston, thus enhancing the useful life of the seal.

Abstract: The invention relates to a method for preparation of perfectly spherical particles of silicagel with controlled particle size and controlled pore diameter, which are suitable as packings for high-speed liquid chromatography and gel permeation chromatography. Free liquid silicic acid is obtained by acidifying of solutions of alkaline metal silicates in organic solvents by organic acids miscible with water in the presence of higher amine as an emulsifier and polymerized to hydrogel in the form of spherical particles. These are isolated and partially hardened by heating above 100.degree. C in a neutral organic medium, e.g. amyl acetate or dibutyl sebacate, to remove a part of water by distillation, then subjected to hydrothermal processing with water under pressure at a temperature above 150.degree. C and eventually stabilized.