6 research outputs found

    RECENT RESEARCH IN VLSI, MEMS AND POWER DEVICES WITH PRACTICAL APPLICATION TO THE ITER AND DREAM PROJECTS

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    Several MEMS (Micro Electro-Mechanical Systems) devices have been analysed and simulated. The new proposed model of SiC MPS (Merged PIN-Schottky) diodes is in full agreement with the real MPS devices. The real size DLL (Dynamic Lattice Liquid) simulator as well as the research on modelling and simulation of modern VLSI devices with practical applications have been presented. In the basis of experience in the field of ATCA (Advanced Telecommunications Computing Architecture) based systems a proof-of-concept DAQ (data acquisition) system for ITER (International Thermonuclear Experimental Reactor) have been proposed

    A Comparative Analysis of Thermoelectric Modules for the Purpose of Ensuring Thermal Comfort in Protective Clothing

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    In recent times, more and more workers are exposed to thermal stress due to climate changes and increased ambient temperature. Demanding physical activities and the use of protective clothing are additional sources of thermal load for workers. Therefore, recent research has focused on the development of protective clothing with a cooling function. Phase change materials, air or liquid, were mainly used for this purpose; only a few publications were concerned the use of thermoelectric modules. This publication analyzes the influence of such factors as supplied current, ambient temperature, and the type of heat sink on the amount of heat flux transferred by a thermoelectric cooler (TEC) and the electric power consumed by it. In the course of laboratory tests, a flexible thermoelectric module and three heat sink variants were tested. For this purpose, a polymer TEGway heat sink, a metal one, and a self-made one based on a superabsorbent were used. The research showed that at a temperature of 30 °C and above, the amount of the heat flux transferred by a TEC with a total area of 58 cm2, and an active area of 10 cm2 should be expected to be from 1 W to 1.5 W. An increase in ambient temperature from 20 to 35 °C caused a significant reduction in the heat flux by about 1 W. The results obtained indicated that the type of heat sink affects the heat flux drawn by the TEC to a statistically significant extent. The heat sink using the evaporation effect turned out to be the most efficient

    Evaluation of Performance and Power Consumption of a Thermoelectric Module-Based Personal Cooling System—A Case Study

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    Thermoelectric (TE) technology is promising for reducing thermal discomfort of workers during their routine professional activities. In this manuscript, a preliminary evaluation of a newly developed personal cooling system (PCS) with flexible TE modules is presented based on an analysis of cooling efficiency and power consumption. For this purpose, tests with human participation were performed involving the monitoring of local skin temperature changes and electrical parameters of the controller. Thanks to TE cooling, a significant reduction of local skin temperature was observed at the beginning of the experiment, reaching as much as 6 °C. However, the observed effect systematically became weaker with time, with the temperature difference decreasing to about 3 °C. Cooling efficiency stayed at the same level over the ambient temperature range from 25 °C to 35 °C. The obtained results showed that a proper fitting of the PCS to the human body is a crucial factor influencing the PCS cooling efficiency

    Analysis of Efficiency of Thermoelectric Personal Cooling System Based on Utility Tests

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    Thermoelectric modules can find practical application in clothing with a cooling function. A personal cooling system using Peltier modules integrated with clothing was developed and tested with the participation of a person. A dedicated electronic controller was designed that enabled the power or temperature to be controlled and recorded. In the research, the influence of heat sinks and the method of controlling the operation of the module on the cooling efficiency was assessed. The research was aimed at selecting the operating mode of the controller and choosing the arrangement of modules comparing cooling efficiency. The research showed that by selection of appropriate controlling mode, the electric power used can be reduced while keeping the cooling efficiency at the same level. The location of Peltier modules in places where they can tightly adhere to the body increases their performance

    The Responses of Bioactive Betanin Pigment and Its Derivatives from a Red Beetroot (Beta vulgaris L.) Betalain-Rich Extract to Hypochlorous Acid

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    Neutrophils produce hypochlorous acid (HOCl) as well as other reactive oxygen species as part of a natural innate immune response in the human body; however, excessive levels of HOCl can ultimately be detrimental to health. Recent reports suggest that betacyanin plant pigments can act as potent scavengers of inflammatory factors and are notably effective against HOCl. Comparison of the in vitro anti-hypochlorite activities of a novel betalain-rich red beetroot (Beta vulgaris L.) extract with its pure betalainic pigments revealed that the extract had the highest anti-hypochlorite activity, far exceeding the activity of all of the betalainic derivatives and selected reference antioxidants. This suggests that it may be an important food-based candidate for management of inflammatory conditions induced by excessive HOCl production. Among all pigments studied, betanidin exhibited the highest activity across the pH range

    Metabolite Profiling Analysis and the Correlation with Biological Activity of Betalain-Rich <i>Portulaca grandiflora</i> Hook. Extracts

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    The aim of the study was to evaluate the possible correlation between the bioactivity and the phytochemical profile of four betalain-rich extracts from Portulaca grandiflora Hook. The HPLC-DAD-ESI-MS analysis indicated the presence of 19 betaxanthins and two betacyanins. The highest concentrations of betaxanthins (982 mg/100 g DE) and betacyanins (650 mg/100 g DE) were noticed in orange and purple flowers extracts, respectively. The HPLC-DAD-ESI-HRMS/MS analyses revealed the presence of a total of 71 compounds. Fifteen new betaxanthins and fifty other metabolites were identified for the first time. The antioxidant activity of the studied flower extracts increased in the sequence of yellow P. grandiflora extracts were non-toxic to normal VERO cells. No significant antiviral activity towards Human Herpesvirus type 1 was observed (62 µg/mL). Among the tested varieties, the purple one showed anticancer selectivity towards colon carcinoma cells (RKO)
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