Search

Microwave assisted extraction (MAE) has been investigated for its potential to aid in extraction of soymilk from soybeans. A batch type grinding cum microwave heating unit was specifically designed and developed for this purpose. MAE of soymilk has resulted in significant increase (p < 0.05) in extraction yield (24%) and protein content (44.4%) as compared to conventional soymilk. Protein characteristics such as protein solubility and protein digestibility of extracted soymilk also showed significant increase (p < 0.05) with respect to conventional milk. The influence of microwave process parameters including microwave power level (540–810W), target temperature (70–90 °C) and stirring speed (140–180 RPM) on protein characteristic of soymilk were analysed. Microwave power level and target temperature were significant (p < 0.05) parameters for the extraction process. The optimal MAE conditions were power level of 675W, target temperature of 80 °C and stirring speed of 160 RPM. • Microwave assisted extraction has been proven as an effective method to increase extraction yield and quality of soymilk. • Yield, protein content and protein solubility of soymilk was increased by 24%, 44.4% and 94.6% respectively by this method. • Microwave power and target temperature were significant for yield and quality of soymilk. • SEM imaging revealed increased breakdown of soybean cell wall structure. This attributes to the success of MAE. [ABSTRACT FROM AUTHOR]

Abstract The present work aims to develop the method for indirect determination of the magnetron target temperature. This method is based on the measurements of heating kinetic curves of the thermocouple sensor's sensing element. The measurements were performed during operation of the magnetrons with cold and hot titanium targets. In order to calculate the hot target temperature, a transcendental equation was derived using the Stefan-Boltzmann law and the Hertz-Knudsen equation. In the general case, the equation uses the difference of the fluxes transferred to the sensing element. The study revealed that in the target temperature range of 1000–1500 °C, the influence of the heat flux transferred by the evaporated atoms of the titanium target on the substrate temperature can be neglected. And the heat fluxes caused by the gas discharge with a current density in the range of 50–100 mA/cm2 have a significant influence on the substrate temperature. Highlights • Target temperature calculation based on substrate temperature is highly accurate. • Heat flux of the evaporated titanium target atoms negligibly impacts substrate. • At the hot target temperature of 1500 °C only thermal radiation impacts the substrate. • Substrate temperature is strongly affected by the gas discharge heat flux. [ABSTRACT FROM AUTHOR]

Body temperature (T b ) is one of the most influential factors affecting physiological processes in ectothermic animals. Reptiles use behaviours such as shuttling, and postural and orientation adjustments to ensure that T b remains close to a target. It is thought that target body temperature (T target ) is aligned to the physiological and behavioural thermal optima of the animal. The Sungazer ( Smaug giganteus ), a Threatened lizard species, is unique amongst the Cordylidae in that lizards inhabit self-excavated burrows in open grasslands, a habitat in which there are few exposed rock basking sites. In this situation, T b s are likely to be greatly influenced by postural and orientation adjustments during basking. We measured T b s using modified iButtons, and calculated T target of free-ranging Sungazers in order to assess the impact of body posture and orientation in the thermoregulation of the species. We used camera traps to record lizard behaviour at burrow entrances and aligned these measures to measures of T b . T target was 30 ± 1.4 °C, and T b s remained within this range for 371 ± 162 min per day. The anterior body-up postures resulted in faster heating and higher T b s. Lizards heated faster when facing away from the sun and spent proportionally more time in this orientation in the morning when T b s were lower than T target . Our findings suggest that their wide behavioural repertoire allows Sungazers to thermoregulate effectively over a broad range of environmental conditions and may thus be able to effectively respond to changing climatic conditions. [ABSTRACT FROM AUTHOR]

Abstract: The method of electric preheating pipelines in the district heating system was introduced. The thermal–structural coupling analysis was used for the electric preheating insulation pipe by ANSYS. The three-dimensional transient finite element model of electric preheating pipeline in the district heating system is established according to the principle of thermology and mechanics. Through the experiment, the result obtained with experiments agrees with the finite element result. And it makes theoretical deduction and experimental analysis to electric preheating method. By analyzing energy, the current of electric preheating has been obtained. Basing on the test data of measuring current of several heating pipelines, these formulas have advantage of easy calculation, wide applications, high reliability and less error rate. [Copyright &y& Elsevier]

Abstract: Surface modification with high-power glow discharges is a promising physical vapor deposition (PVD) technology for industrial usage. A metal ion density higher than 1018 m−3 can be obtained due to a high-power input in the plasma. In the present paper, titanium films were deposited on Si (100) substrates using high-power impulse magnetron sputtering (HIPIMS). The pulse duration was varied to investigate the deposition rate and the titanium film structure. The plasma source was an unbalanced magnetron sputtering (UBMS) discharge generation system. The deposition rate was correlated to the electrical characteristics. There was an instantaneous power threshold of approximately 36 kW to significantly increase the deposition rate by 4–5 times. The deposition rate increased linearly with respect to the average power until the average power reached 5.6 kW (about 30 W/cm2 for a total area of the target), and an 83% increase of the deposition rate from the linear relationship was observed. The increase of the deposition rate was possibly closely related to the so-called thermal spike, where the target temperature increases due to a high power input to the target. The surface morphology and the crystalline structure of the films were studied for a variety of pulse durations, and the results were compared to the case of the direct-current magnetron sputtering (dcMS) process. The titanium films at an average power of 1.2 kW and a pulse duration of 50 μs have a smaller crystalline size and a smoother surface than those at an average power of 825 W by dcMS. The crystal orientation (101) was dominated when the pulse duration was lengthened to 180 μs, although the (002) orientation was dominant in dcMS. The crystal size and the surface roughness increased significantly when the pulse duration was increased from 50 μs to 180 μs in HIPIMS. The consumed power in the plasma by HIPIMS can be an important parameter for the crystal size and the structure. [Copyright &y& Elsevier]

Abstract: Thermal analysis was performed for a titanium drive-in target of a D–D neutron generator. Computational fluid dynamics code CFX-5 was used in this study. To define the heat flux term for the thermal analysis, beam current profile was measured. Temperature of the target was calculated at some of the operating conditions. The cooling performance of the target was evaluated by means of the comparison of the calculated maximum target temperature and the critical temperature of titanium. [Copyright &y& Elsevier]

Abstract: Thermal shock resistance is one of the most important parameters in Ultra-High Temperature Ceramics (UHTCs) since it determines their performance in various applications. In this paper, due to the fact that the material parameters of UHTCs are very sensitive to the variations of temperature, the temperature-dependent thermal shock resistance parameters of UHTCS are studied using an analytical model. The effects of target temperature on the thermal shock behavior of UHTCs thermal protection system (TPS) under active cooling are examined. The calculated results show that thermal shock behavior of the UHTCs’ TPS is strongly affected by the target temperature. [Copyright &y& Elsevier]

Abstract: Titanium nitride or dioxide coatings have been reactively sputter-deposited under unstable sputtering conditions using a cold or hot target. We have shown that increasing the sputtered titanium flux in cold target sputtering (CTS), by increasing either the discharge current or the discharge voltage, increases the metalloid content in the coating deposited when the target operates at the higher reactive gas flow rate of the elemental sputtering mode. Using a hot target allows a perfect stabilisation of the process in the presence of an argon–nitrogen discharge, whereas only a slight stabilisation occurs when the sputtering stage takes place in argon–oxygen mixtures. It is shown that the stabilisation effect of hot target sputtering (HTS) is due to the strong increase of reactive species diffusion into the bulk target, which is more pronounced with nitrogen than with oxygen, as soon as the target heats up to the α-Ti→β-Ti transformation temperature. [Copyright &y& Elsevier]

Abstract: In this work, the formulas for the absorption coefficient and the absorptivity depending on target temperature are derived from Maxwell Equations and the Lambert–Beer''s law. A new theoretical model of laser ablation considering the temperature dependence of the absorption coefficient and the absorptivity has been developed. Then, as an example of Copper target, a finite difference method is employed to simulate the space-dependent and time-dependent absorption coefficient, absorptivity and temperature, as well as the time-dependent melt depth. The temperature evolution is compared with the result obtained from the heat conduction model taking the absorption coefficient and the absorptivity as constants. It is shown that the time-dependent absorption coefficient and absorptivity play an important role during the radiation of laser. Our calculated melt depth evolution is in better agreement with the experimental data than the result of the heat conduction model that regards the absorption coefficient and absorptivity as constants. Meanwhile, the corresponding physical mechanism is analyzed theoretically in detail. [Copyright &y& Elsevier]

The processes of ion back-scattering from the surfaces of various targets have been studied by means of the computer simulation (different modifications of the Monte-Carlo method). The analysis of the experimental and calculated data allows proposing the mechanism explaining the target temperature dependence of the shapes of the back-scattered ion spectra. The formula satisfactorily describing the dependence under study has been developed. [Copyright &y& Elsevier]

In this study, the influence of distance from focusing-lens to target-surface (DFTT) on the spectral characteristics of femtosecond and nanosecond laser-ablated Cu plasmas for different target temperatures was compared in air. The results showed that the spectral intensities were dependent on the DFTT and the target temperature. The spectral intensities increased with an up-regulation in the target temperature. In addition, as the target temperature increased, the maximum spectral emission and electron temperature moved away from the focusing-lens in the case of the femtosecond laser, while the maximum spectral emission and electron temperature moved closer to the focusing-lens in the case of the nanosecond laser. These phenomena were mainly based on the different pulse widths between femtosecond and nanosecond laser-ablated mechanisms. [Display omitted] • Increasing the target temperature can enhance the spectral intensity of the Cu plasmas. • Spectral intensities firstly increased, and then dropped with an increase in the DFTT. • Spectral maximum in fs moved away from focusing-lens as the target temperature increased. • Spectral maximum in ns moved close to focusing-lens as the target temperature increased. [ABSTRACT FROM AUTHOR]

Thermal properties of the magnetron discharge with uncooled copper and chromium targets were studied experimentally and theoretically for DC and long HiPIMS (L-HiPIMS) operation modes. A set of thermal fluxes was considered to build a numerical model of the hot target exposed to DC and high-power pulsed plasma. The modeling results were tested in the experiments. The temperature of targets was measured directly in course of magnetron discharge operation with an elaborated contact thermocouple method. The measurements were made in two modes. At first the temporal evolution of temperature was recorded for a fixed applied discharge power. The results were found to well agree with temperature values expected from calculations. At 2 kW power, it takes ~50 s to reach the melting point of copper. The steady-state temperature values were also measured for a number of discharge power levels. The obtained dependence clearly demonstrated that the main mechanisms of the target heat balance at high temperatures are surface radiation and heat transfer due to thermal conductivity of the heat insulation supports between the target and water-cooled cathode. The parameters of DC hot target magnetron were compared to the high-power pulsed regime with the pulse-on time 20 ms. A promising method of a hot target magnetron discharge operation was considered that involves applying long (>20 ms) high-power pulses to the target pre-heated in the DC mode during the pulse-off period. • Thermal processes in hot target DC and L-HiPIMS modes were considered. • Temperature of uncooled Cu and Cr targets was measured with a contact method directly during the DC magnetron operation. • The results of numerical modeling agree with the experimental temperature data. • Pre-heated hot target L-HiPIMS pulse was modeled. [ABSTRACT FROM AUTHOR]