Topics discussed in this unit on the borderline of chemistry, physics and biology are used in many areas of life. For example, the RGB scale is used e.g. in the case of monitors, computer and television. The composition of colours, the colour mixing is applied in painting (also in the room one). It is the practical knowledge, that may be useful in the life of each student. Interactive websites that show demonstrate the mixing the colours are also worth visiting:
Optical phenomena are widely used in technology: the reflection of light – in the pier glasses, mirrors, reflectors; the refraction of light – in lenses and devices containing lenses; the total internal reflection – in optical fibres; polarization in displays. Prisms are used in sights and rangefinders.
The UV lamps are applied for instance in:
- polygraphy – drying and curing of paints and varnishes (digital printing, pad printing and offset printing, and also the furniture industry), exposures of templates for screen printing, production of packaging for foods (the UV flexo),
- curing of adhesives and nail tips,
- dealing with harmful microorganisms and disinfection of:
- transporters and conveyor belts (the food, chemical and cosmetic industry)
- air (laboratories, the so-called “cleanrooms” e.g. in the pharmaceuticals industry, offices, hospitals)
- water – in the water supply systems, swimming pools and aquariums
The infrared lamp (Sollux) in used for the treatment of such disorders as ear, nose and throat diseases, it is also used in case of bruises, as well as in the treatment of rheumatic diseases. It is also widely applied in dermatology and cosmetology e.g. in the treatment of acne. Infrared lamps irradiation helps in the muscle diseases, rheumatism, arthritis and back pain. Moreover, suchirradiation will strengthen the immune system and may suppress the development of the disease when the first symptoms of colds occur. Infrared rays have also relaxing and calming effects. Heat emitted by the infrared lamps penetrates deep into the skin, stimulates the metabolism and the blood circulation, and thus may be useful in the fight against cellulite. The lamps are being increasingly used for hair drying in hairdressing salons and beauty salons, as well as for heating churches and cafes in the fall-winter season.
Knowledge about the light and its effects on the skin is used in the production of sunscreen means (creams / foams / sunbathing oils).
Photosensitive materials are used in photography, production of films, and some fax machines.
Mid-infrared spectroscopy is used for: identification of substances of known structure, determination of molecular structure on the basis of group frequency table, determination of the compounds purity, control of the course of the reaction, quantitative analysis, the study of intermolecular interactions.
The near-infrared spectroscopy is used in the study of the moisture content in flour, starch, milk powder, instant coffee, crisps, and also in the analysis of the spectrum of light reflected or emitted by the planets.
Colorimetry is an analytical technique for determining of the concentration of colour solutions through visual comparison of the colour intensity of the test solution with the intensity of the colour of the reference solution. The method is regarded as simple, fast and accurate. Miniature handheld colorimetric kits with colour tables are used in medicine, food testing (beer, alcoholic drinks of a whisky type, and the caramel dye, oils and fats present in them):
measurements of the water parameters in the power industry and the production of industrial water, drinking water and in the wastewater treatment plants:
Colorimetry is widely used for quick estimation of solution pH by means of the calibrated indicator papers. It is one of the methods widely used in the water studies in the laboratories of the National Sanitary Inspection.