This study was conducted with the aim of protecting groundwater, which plays a crucial role in ensuring food quality in the market, preserving public health, and safeguarding the ecosystem, as many regions rely on clean natural groundwater for their population’s survival. The objective of this study was to use the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) for groundwater at 12 stations in the Okhla Industrial Area, Nangloi, and Karol Bagh in the Delhi Region. CCME WQI is an effective tool for assessing groundwater quality and communicating water conditions to various users. The research methodology involved fieldwork from June to October 2020 for three different periods in the year: pre-monsoon, monsoon, and post-monsoon, to observe variations in water quality and differences in various physicochemical properties of water. The CCME WQI was applied using sixteen water quality parameters, fourteen of which were physicochemical parameters and two of which were microbiological parameters. Among the physicochemical parameters were color, odor, pH, turbidity, nitrate, total hardness, iron, chloride, fluoride, total dissolved solids, calcium, magnesium, sulfate, and alkalinity, while the microbiological parameters included the total coliform and Escherichia coli counts. Based on the results obtained from the water quality index, station A9 scored between 0 and 44, indicating the lowest water quality index due to wastewater discharges and industrial contamination. The water quality at other stations also requires attention to achieve excellent ratings. The study concludes that serious measures should be taken for proper management of the area to protect the population from hazardous diseases. The research results show that stations 1, 2, and 10 were rated as excellent, station 12 as good, stations 4, 5, and 8 as moderate, stations 3, 6, and 11 as marginal, and station 9 as the poorest in terms of water quality in the year 2020 during the pre-monsoon, monsoon, and post-monsoon periods. To improve the parameters and groundwater quality, it would be necessary to reduce the impact of industry, anthropogenic–geogenic activities, and domestic activities.

Reinforcing of elastomers by the addition of various nanofillers has led to significant improvements in elastomer properties, and therefore, to the increase of potentials for use as suitable materials for special applications. The aim of this study was to investigate the effects of combinations of two active fillers (carbon black and synthesized silica (50/0; 35/15; 25/25; 15/35; 0/50; phr)) on the morphology, curing, as well as thermal, dynamic-mechanical and mechanical properties of nanocomposites based on the styrene-butadiene rubber as the network precursor. Based on SEM results, the largest agglomerates were observed in the structure of the nanocomposite containing 25 phr of carbon black and 25 phr of SiO2. Determination of curing characteristics indicated that the minimum torque at 100, 150 and 160?C had higher magnitudes for the compounds with silica filler, which is in accordance with the tendency of SiO2 to form filler-filler interactions. Values of the scorch time and the optimal time of crosslinking increased by increasing the silica phr content in the fillers mixture. It could be thus supposed that the fraction of occluded and trapped chains in the structure of elastomer reinforced by SiO2 is higher due to the almost 2-fold higher value of the silica NDBP number as compared to the NDBP number of carbon black particles. On the basis of MDSC results, it was assessed that the addition of combined active fillers had negligible effects on the glass transition temperature, registered at about -47?C for all tested samples. The obtained DMA data, concerning storage moduli in the temperature range from -20 to 0?C, (characteristic for "Payne" effect) are very significant for predictions of the properties of the tyre tread such as the slip resistance on the road on ice and in the wet conditions. The increase of silica content in the combined filler induced a decrease of the dynamic mechanical loss factor of prepared nanocomposites in the temperature range from 40 to 80?C. The obtained results are very important for the structuring of elastomeric materials aimed for production of tyres with reduced rolling resistance and fuel consumption. The elastomer containing the highest content of carbon black showed the highest value of the tensile strength (21.8 MPa). The abrasion resistance of the synthesized nanocomposites increased as the silica content was reduced in the combined fillers.

Light is an integral part of our environment. Its effect on humans is significant - it affects not only their visual performance or well-being but also other extra-visual functions of the body, which affect the quality of their life. Lack of light causes various health problems of physiological or psychological dimensions caused by visual discomfort at the workplace. The presented article describes the possibilities of assessing the visual well-being of the workplace by implementing digital ergonomic tools during the flexible screening of lighting. The introductory part of the article is focused on a theoretical description of the issues in the field and then the tools of digital ergonomics are introduced, through which the experiment is carried out. The main part of the article provides an overview of the achieved results and describes the conclusions based on the analysis. Regarding the achieved results, at the end of the article, there is a description of the possibilities of ensuring rationalization measures and the direction of further research.

The basic questions that arise when maintaining an automated electric drive relate to the safety and reliability of the elements in operation. The maintenance strategy of these elements is planned to start from the basic facts related to the plant’s importance, type and purpose. The main purpose of maintenance is the timely detection of a fault and its elimination, i.e. ensuring continuous operation of the plant. In this work, the operation of the cable car was analyzed by monitoring the reliability of the electric drive. An analysis of the significance of reliability coefficients is a potentially new method for maintenance planning. The aim of the research was to define a new strategy for the maintenance of the facility and ensure the maximum safety of skiers through the analysis of previous events. Research is based on coefficients that indicate the reliability, frequency of failures, availability and unavailability of the elements that make up a drive. The essence of the conducted research is based on a new strategy for planning and maintaining such a facility, aiming to ensure skiers’ safety and protection.

Various strategies for achieving a functional poly(lactic acid) (PLA) have been developed such as ring-opening copolymerization with a functional monomer, the use of functional initiator and various post polymerization modifications. It is possible to obtain the star shaped polymer using natural oil with at least three OH groups as an initiator. It was estimated that despite of low-molecular mass of star-shaped PLA, the hydrophobic castor oil central core influenced the slow degradation rate in the case of injectable biomedical application. The star-shaped polymers with low-molecular-mass have a lower melt viscosity correlated with linear counterparts. In soft tissue reparation the polymer viscosity increases with fluid body contact and the solid implant can be formed. To ensure liquid state at injection temperature the low molar mass polymer is favorable. There is a particular size for each macromolecular chains at which chain entanglement occurs. In this work the influence of the l-lactide (LA) and the castor oil (CO) contents on the size of biodegradable branched polyester polyols was studied. The average molecular masses of synthesized polymers were estimated by GPC procedure. In sample formulations the [LA]/[CO] ratios were from to 113 to 533. Mn values for obtained polymers were from 5000 to 20000 Da. The molecular mass distribution for the resulting polymers was between 1.09 and 1.37.