We employ a variant of the joint time-frequency analysis (JTFA) for identifying transient, temperature-dependent noise emitted from porous journal bearings operated at temperatures between -40°C and 0°C. This phenomenon, called "cold squealing", is difficult to reproduce in laboratory environments, as it requires a suitable (and typically system-specific) resonator to occur. We systematically tested real-world bearings impregnated with various oils on a custom-designed experimental rig, fitted with a coolable sample holder and a vibration sensor, over a range of rotational speeds. By analyzing temperature-differential JTFA signal maps, we succeeded in detecting transient cold-squealing as well as ranking the bearing lubricants according to their low-temperature quiet running properties.

In an urbanized context, the need for a thorough understanding of the relationship between plants and human well-being becomes more and more important. It is documented that plants in the work environment bring a number of benefits, not only aesthetic but also psychological and physical benefits. The present study sought to determine if ornamental plants have positive effects on a wide range of factors such as productivity, mood states, creativity and stress on employees in an real organizational context. Questionnaire with 15 statements was used as method to examine the employees perceptions, applied before, after the installation of plants for each office and in swich phase. The study results were examined to determine if are statistically significant differences between the two groups at every stage. There were significant differences between the experimental and control group over the work environment. Research has found that for a better perceived working environment is a close link between creativity, reduced stress and job satisfaction. Results support the evidence of the psychological benefits of ornamental plants on employees and a general preference for plants. The direct impact of these benefits is on well-being and general performance of companies and the incorporation of ornamental plants in the workplace is deemed imperative for the future organizations to achieve the desired results.

Air pollution has become a mass phenomenon, a major and global problem of modern society, affecting billions of people and environment. People are exposed to various levels of pollutants not just in the outdoor environment, but also in indoors. The quality of life and well-being of employees can be increased by incorporating ornamental plants in the work environment. Among the great variety of plants species able to remove/reduce indoor air pollutants Dracaena deremensis, Sansevieria trifasciata and Ficus elastica were hereby investigated. Their ability to remove chemical pollutants was evaluated in real-life conditions and the changes induced by the environmental stress on the structure and biochemical composition of the plants leaves were evidenced by the Fourier transform infrared spectroscopy. The most pronounced concentration decrease was noticed for the CO2 (58.33% removed concentration), whereas the mean value of the removed concentration of other chemical pollutants was of ≈25%. The Fourier transform infrared spectra analysis revealed that, although the plants are subjected to the chemical pollutants action, they maintain the structure by adjusting their metabolism. A decrease in the overall protein contribution in the amide bands and an increase of the bands assigned to polysaccharide vibrations, illustrate the consequences of the pollution action. Moreover, the chlorophyll presence is evidenced in the IR spectra of all samples by the bands around 1040, 1445, 1620, and 1735 cm −1 . The results show that the Fourier transform infrared spectra are an important source of information for the rapid characterization of the chemical structure of the biological systems under environmental stress.