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Laccases are enzymes belonging to the Oxidoreductases class. These enzymes may be good biocatalysts for different processes, at laboratory and industrial levels. A successful use at industrial scale demands a higher stability of the enzyme. As an easy way to obtain longer life biocatalysts, the immobilization process is recommended. Thus, the paper presents different ways of obtaining new biocatalysts by a laccase covalent immobilization on a macroporous carrier based on poly(vinyl alcohol) cryogel. Different procedures of covalent immobilization are described, the newly obtained biocatalysts being characterized. According to the experimental data, the stability of the immobilized enzyme increased and the pH profile changed, compared with those of the free enzyme.

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Apart from the strict elements related to the organization of the work place of the equipment and operated machines, the productivity of an operator or factory is addiction on other elements of ergonomics such as: temperature and relative humidity of the air, speed of air currents, noise level, level vibrations and their directions, CO2 level, brightness, radiation level, chromatic from the production hall, ambient music and its volume. In this paper we analyzed the influence of light intensity and ambient music on productivity in a clothing section in which 70-80 workers manufacture sports equipment in which dark colours predominate, for children, women and men. Some levels of light intensity were chosen, different from those provided in standards (400 lx for light colours and 700 lx for dark colours), and for ambient music we chose as a volume level, with 5-10 dB above the average noise level in the production hall. We mention that in this section is not used ambient music currently. We mention that all the laboratory equipment used are in the SIProM laboratory, (study, hygiene and labor protection ), within the Faculty of Engineering, and the collective of this study was an interdisciplinary one formed by researchers from the Textile Industry field and a researcher from the Accounting field. Initially, timings were made to determine the execution times for certain technological phases, namely: the overlock machine, the elastic applicator machine and the simple machine, for zipper application. These measurements were made under the usual working conditions in this hall production, for lighting levels of 550-750 lx and without ambient music. At the end of the study, data on labour efficiency were processed and calculations were made regarding labour costs for workers who served the three types of machines. For a complete image of the activity of the entire section, production department, the information was processed for the entire section, both in terms of productivity per worker, for each machine, and the costs for manpower were calculated for the nine weeks of the our study. For a more complete information of the activity of the whole section, the results were extended for the whole section, both in terms of efficiency per worker, for each machine and the costs for the work of the entire group of workers were calculated.

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In this paper we compared a classic and an unconventional system for the manufacturing of cotton yarns 100%. For this comparison we analyzed the complexity of classical and unconventional technological lines, the differences between the yarn structures, the fields of use of the yarns, as well as a cost-benefit analysis. From the point of view of the complexity of the technological lines and implicitly of all the necessary adjustments we can say that the technological line for the unconventional system is much easy and shorter. Considering the complexity of technological lines, we can say that the human resources requirement is much lower for unconventional technological lines. For this we realised a comparative calculation of costs for workers and for taxes that an employer has to pay. Starting from the complexity of the technological lines, the unconventional technological line being shorter with two machines, we made a comparative calculation of the energy consumption. The calculations were made for a spinning mill with a production of 4000 t/year, a typical production for a medium size. From the point of view of the production costs and investment effort, we can say that the unconventional system is better, but considering the structure of the yarns we can say that the destinations are different, so the unconventional yarns are better suited to certain products, such as the jeans clothing.

In the current context of involvement in the fight against COVID 19 wearing protective masks are strictly necessary to limit the spread of the virus SARS-CoV2. Since the appearance of this virus, solutions have been sought to cover the needs of masks for the population and also to improve their wearing comfort compared to nonwoven fabric (TNT) masks. These masks are made of chemical fibres and it is recommended to be worn for a maximum of 4-8 hours and then they must be discarded. In this study, two types of masks from wool and silk blended knitted fabrics were manufactured and analysed. The masks were initially subjected to manual ironing sterilization and disinfection. Subsequently, several analyses were performed: specific mass, density, abrasion and pilling resistance, colourfastness to crocking, colour fastness to accelerated laundering, air permeability, bacterial filtration efficiency and breathability. The analysed masks can be washed and disinfected at home and are reusable. This aspect offers a strong sense of safety for the user, but also has beneficial effects on environmental protection. Even so, they do not correspond to bacterial filtration efficiency. Eventually, the comfort perception of about 300 volunteers was also taken into consideration.