Distribution of temperature field in phantom of hand with microwave radiation

The present work presents the results of phantom of human hand simulation with the dielectric properties, very similar with human tissues properties. The simulation was conducted with using “CST Studio” software. The phantom was made by a “papier-mâché” method. The thermal field distribution was measured twice: for the simulation of phantom in “CST Studio” software, and for the phantom filled with dispersed meat of pork, the power was 2.45 GHz. The heating profile of certain points on phantom, including fingers, has been studied. It is shown that the heating profile of fingers zone is different from heating profile of wrist and forearm. The obtained experimental data have shown the possibility of using microwave radiation for deep cold injuries treatment.

WIRELESS METHANE DETECTOR WITH TEMPERATURE MODULATED HEATING PROFILE

The results of development of an autonomous methane detector in a dynamic measurement mode are presented. Industrial catalytic sensor was used as a sensitive element. To prevent burnout of the catalytic sensor microheater which often occurs during pulsed heating, the special form of heating pulse has been developed. The proposed dynamic mode of the sensor heating provides the measurements with low power consumption and the required level of safety in the measurement range of pre-explosive methane concentrations from 0.1 to 2 vol.%. Based on the analysis of the obtained results, the estimation of autonomous operating time of the detector is given.

Correlation of heating profile with calcination temperature for the extraction of nano hydroxyapatite (Nano-HAp) derived from bone

Bone is one of the major sources of hydroxyapatite (HAp) in the form of calcium phosphate. The increasing demand for HAp has brought much interest in research line to find the best method for its production either synthetically or naturally. Calcination of natural bone is a common heat treatment method for production of HAp. However, the optimum temperature of calcination depends on source and heating profile of the bone. Therefore, this study aimed to determine heating profile and the optimum calcination temperature of Nano-hyroxyapatite (Nano-HAp) extracted from spotted sardinella (Amblygaster sirm) bone. Characterization of Nano-HAp was carried out using thermogravimetric analysis (TGA), chromameter and X-ray diffraction (XRD) spectroscopy. The composition of protein, ash, moisture and lipid content of raw bone (RB) were 1.08%, 50.98%, 10.47% and 3.78%, respectively. Results demonstrated that the optimum temperature for extracted nano-hydroxyapatite (HAp-1) was 700°C based on yield percentage (55%) and colour changes value (∆E=18). Heating profile of raw bone demonstrated the highest reduction of weight loss percentage (320°C to 610°C=36%); which determined the melting point of the bone that acted as a supporting analysis for calcination. XRD confirmed the crystallinity phase of HAp-1 particle similar to the standard peak of HAp, (PDF No: 1-1008) and comparable with the standard HAp. Based on the heating profile and colour changes value, the findings demonstrated that the calcination of HAp from bone of spotted sardinella (Amblygaster sirm) could be carried out at an optimum temperature of 700°C. Overall findings have suggested that the optimum calcination temperature obtainedmay contribute to the development of optimal method for the extraction of HAp via heat treatment process with different fish species.

The Empirical Influences of Tibetan Plateau Soil Moisture on South Asian Monsoon Onset

The South Asian High (SAH) location and intensity are linked with the Tibetan Plateau (TP) and Yangtze River basin latent heating. The existing feedbacks of SAH variability is rarely linked with TP soil moisture regulated energy fluxes. In this study, remotely sensed soil moisture and global atmospheric reanalysis products are used to quantify the relationship between the TP spring (April, May, June) soil moisture with SAH and South Asian (SA) monsoon onset during 1988–2008. The diagnostic analysis infers that the SAH exhibits a significant correlation (R ≥ 0.90) with TP spring soil moisture and monsoon onset indices (R≥ -0.56−-0.61). During the early and late monsoon onset, a significant anomalous soil moisture regime influenced the surface energy fluxes, which affected the vertical diabatic heating profile. The diabatic heating profile affects the TP ascending motion and SAH intensity, which leads to regional monsoon circulation changes and onset. An asymmetric SAH movement in the upper troposphere appears before the early and late monsoon onset composites and drives the lower tropospheric westerlies/easterlies winds towards the continental SA. The wind shear and transition from prevailing easterlies into westerlies during the pre-onset, onset, and post-onset pentad results in strong/weak ascent in the Bay of Bengal and advances into continental regions. The onset- mechanism further suggested intensified/weaker westerlies/easterlies during early/late onset composites. The SAH intensity and movement are linked with TP soil moisture, which exhibits teleconnections with the regional circulation pattern. A detailed model experiment will be conducted to verify the influence of soil moisture as a driver of energy fluxes and SA monsoon onset.

Distributed Activation Energy Modelling Using a Parabolic Heating Profile

This work investigates the thermal decomposition of forest waste for a non-linear temperature distribution inside the pyrolysis reactor. Quantitative analysis of the distributed activation energy model is explained graphically. It has been assumed that thermal profile varies according to the general parabolic equation with the initial condition (0, T0). The approximated solution of the non-analytical integral is determined by the Laplace integral method. The integral limit for the distributed activation energy model (DAEM) is found to vary from 211 to 810 kJ·mol−1; whereas the frequency factor (the first-order reactions) for the corresponding range of the activation energy lies in the domain of 400–2000 min−1. The acceleration in the char formation has been found for the reactions other than that of the first order.

MICROWAVE PYROLYSIS OF BIOMASS IN A ROTATORY KILN REACTOR: DEEP CHARACTERIZATION AND COMPARATIVE ANALYSIS OF PYROLYTIC LIQUIDS PRODUCTS

The pursuit of sustainable relationship between the production and consumption of energy has accelerated the research into new fuels alternatives, and mainly focused on new technologies for biomass based fuels. Microwave pyrolysis of biomass is a relatively new process which has been long recognized to provide better quality bio-products in shorter reaction time due to the direct sample heating and the particular heating profile resulting from the interaction of biomass with the electric field component of an electromagnetic wave [1,2]. During the course of this research, flax shives were pyrolysed using a rotatory kiln reactor inside a microwave single mode cavity using a range of power between 100 and 200 watts, to reach a temperature range between 450 °C and 650°C. The liquid bio-oil samples recovered in each case were analyzed though gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID) to identify and quantify the different molecules presents and paying a particular attention to the BTX’s concentration. More than two hundred compounds were identified and grouped into families such as carboxylic acids, alcools, sugars for a deep analysis of the results. The effect of the operating conditions on the proportion of gas, liquid and char produced were studied as well as some properties of the pyrolysis products. In most cases, carboxylic acids were the dominating chemical group present. It was also noticed that the increase of temperature enhanced the carboxylic acids production and diminished the production of other groups, as sugars. Finally, pyrolysis oils were produced in higher quantities by microwaves than in a classical oven and showed a different composition. The examination of the pyrolytic liquid products from different biomass components helped to determine the provenance of each molecule family. On the operational side, the rotatory kiln reactor provided a fast and homogeneous heating profile inside the reactor, desired for fast pyrolysis. The high temperature was maintained without making hot spots during the reaction time. The microwave irradiation setup consisted in a single-mode cavity, a system of plungers, incident and reflected power monitors, an isolator and a 2.45 GHz continuous microwave generator with a power upper limit of 2000 watts. The plunger system was calibrated to maintain a range of reflective wave between 5 and 15%, taking advantage of a minimum of 85 percent of the applied power. In conclusion, the developed microwave pyrolysis process gives a clear way to produce an exploitable bio-oil with enhanced properties. References Beneroso, D., Monti, T., Kostas, E., Robinson, J., CEJ, 2017.,316, 481- 498. Autunes E., Jacob M., Brodie, G., Schneider, A., JAAP, 2018,129, 93-100.