SOUTHERN JOURNAL OF SCIENCES

An indicator of the health of the human body in the state of the oral mucosa. Mechanical and chemical factors constantly influence it. At the first stage of the study, a comparative analysis of the frequency of various forms of traumatic injuries of the oral mucosa was carried out. The distribution of patients into groups was also carried out, depending on the medicinal product used. Then clinical examinations were carried out. After that, the therapy of traumatic erosive and ulcerative lesions of the oral mucosa began. The developed method for treating traumatic lesions of the oral mucosa with medicine based on phytoecdysteroids provides for eliminating the traumatic factor, applying ointment based on phytoecdysteroids to the dried out focus twice a day. The use of phyto-ointment leads to complete repair of traumatic erosive and ulcerative lesions of the oral mucosa on average by the eighth day from the start of treatment; a similar effect with the use of "Solcoseryl dental adhesive paste" is achieved by the tenth day, and the gel "Cholisal Dental" - at a later date, which is confirmed in this study. The most significant positive effect on the level of quality of life associated with the effectiveness of treatment of traumatic erosive and ulcerative lesions of the oral mucosa in comparison with the dental “Solcoseryl dental adhesive paste” and the gel “Cholisal Dental” is exerted by phyto-ointment, where a decrease in the total points was recorded. When conducting routine examinations of patients, it is necessary to pay attention to the oral mucosa damage. Moreover, in treating traumatic injuries of the oral mucosa, it is recommended to use phytoointment, which contains phytoecdysteroids.

Background: MQ-series gas sensors belong to the metal oxide semiconductor (MOS) family of sensors that can sense the presence of many gases. These sensors find their application in gas alarm systems as key components. While necessary sensor circuit output voltage value for alarm point in a stand-alone gas alarm system is desirable, but what exact combination of the sensor circuit parameters is required? Hitherto, the determination of these circuit parameters has not been given much attention in the research community. Aim: the purpose of this work is to explore a structured graphical approach of determination of MQ series gas sensor circuit parameters for a stand-alone gas alarm system that yields desired sensor circuit output voltage value for the alarm point; the main objective of the study was to develop mathematical model equations that relate the: (i) sensor resistance (RS) with the gas concentration (x) and the sensor resistance at standard calibration concentration of the sensor base gas in the clean air (Ro) and (ii) sensor circuit output voltage (VRL), load resistance (RL) and sensor resistance (RS). It is expected from the model equations developed that graphical correlations of the sensor circuits parameters will be generated. Using these graphs for a particular case of an MQ-4 gas sensor under the influence of LPG, the parameters that yield desired sensor circuit output voltage of 2V for 1000 ppm of LPG alarm point will be determined. Methods: Model equations were developed for the sensor dynamics, and based on these model equations, graphs for the determination of required sensor parameters were plotted for a case of MQ-4 gas sensor response to LPG. Results and Discussion: The results yielded optimal values for R_O,R_S and R_L of 20 kΩ, 30 kΩ and 20 kΩ respectively, for alarm settings of 1000 ppm and a desired sensor circuit output voltage of 2 V. Based on determined parameters, the calibration equation for determination of best concentration value for a given value of emulated LPG concentration was developed. Using the method proposed in this study makes the process of determining the MQ-series gas sensor circuit parameters less cumbersome as their value can easily be obtained from the resulting graphs. Conclusions: a structured graphical approach for determination of MQ-series gas sensor circuit parameters for alarm points in a stand-alone gas alarm system showed that using MQ-4 gas sensor and LPG as the target gas, and for a sensor circuit output voltage of 2 V for alarm point at 1000 ppm of LPG, the corresponding value of R_O, R_S and R_L obtained were 20 kΩ, 30 kΩ, and 20 kΩ respectively. Hence, a structured graphical approach is suitable for determining MQ series gas sensor circuit parameters for a stand-alone gas alarm system under the influence of its associated gases.

Background: Recently, research has been carried out to improve the efficiency of electronic devices in general. With the commercial search for consolidated materials and the growth in demand with monitoring of costs, research has sought to minimize these effects with the replacement or functionalization of other substances, which may be applied at lower costs without compromising operating yields already achieved. Objective: This work aimed to obtain molecular modeling and reactivity parameters of -caprolactam and o-phenanthroline to evaluate the interaction capacity in the formation of molecular systems. Conductance measurements were taken to observe the electrolytic behavior. Infrared and UV-visible spectra were recorded to characterize vibrational transitions and evaluate spectrochemical properties. Methods: The WebLab program was used to obtain structural data and calculate reactivity parameters. Conductance was obtained in QUIMIS Q-405 equipment. IR spectra were recorded on PERKIN ELMER FRONTIER equipment. UV-vis spectra were recorded in a SHIMADZU equipment 200 – 1000 nm range to record the main transitions. Results and Discussions: Electron donor atoms are centered mainly on oxygen and nitrogen, respectively, which are sterically more favorable. The behavior was non-electrolyte. Groups with vibrational transitions sensitive to chemical interactions are comprised of C=N, C-N, and C=O bonds. The  parameter indicates transitions in the 190 – 300 nm region and the near-infrared, and the oscillator strength is typical of molecules used as dyes and sensitizers in optical light-emitting systems or light-to-electricity converters. Conclusions: We observed that these ligands have a donor capacity for the formation of complex systems that meet the need for electron transfer in optical pumping devices for the intensification of transitions or radiation converters, which can also be applied in radiation-to-electricity converter systems.