Noticeable Heating Research Articles

Transformations of the Image of Turkey in the Soviet Satirical Press of the 1940s — 1950s

The article analyzes the transformation of the image of Turkey in the Soviet satirical press during the 1940s and 1950s. That was a period characterized by a noticeable heating of the Soviet-Turkish relations due to the neutrality policy of Turkey during the Second World War. Using the methodological tools of imagology, the author explores the content diversity and polyphony of political subtexts of cartoons and journalistic essays of the Soviet satirical magazine “Krokodil” during the period of 1944—1953. The substantial deconstruction of the materials allows us to trace the nature of the transformation of the image of Turkey and the perception of Turkish political figures in the USSR. The study revealed the correlation of cartoons and satirical images of Turkey and Turks with the nonlinear dynamics of the development of the Soviet-Turkish relations. If in the mid-1940s individual political figures were mainly criticized, in the late 1940s — early 1950s the focus shifted to criticism of the foreign and domestic political actions of the Republic of Turkey, in particular its involvement in the Korean War (1950—1953), as well as a grotesque depiction of the plight, subordinate position of the Turkish people in relation to the West.

The Brain as a Constructor: What Does the Visual Perception Has in Common With Language?

Halloysite nanotubes (HNTs) with immobilized gold (Au) nanoparticles (NPs) were explored to enhance photoheating of aqueous media under excitation by continuous wave (CW) and nanosecond pulsed lasers with wavelengths close to the plasmonic resonance of Au-NPs. The structure and plasmonic properties of HNTs/Au-NP nanocomposites were analyzed by means of the transmission electron microscopy and optical spectroscopy. A remarkable photothermal effect with initial temperature growth of about 0.5 °C/min was observed for HNTs/Au-NPs’ aqueous suspension under relatively low excitation intensity, while the same photoexcitation of bare HNTs’ aqueous suspension did not result in any noticeable heating. In vitro experiments with Paramecium caudatum unicellular organisms have revealed a strong suppression of the cell viability after photoexcitation. While the average photoheating effect did not exceed 3–4 °C, the cell viability was decreased multifold, especially for the pulsed photoexcitation. The experimental results are explained by the spatially and temporally localized photohyperthermia in the vicinity of Au-NPs. The observed photoheating of HNTs/Au-NP nanocomposite is promising for applications in antibacterial treatment and targeted cancer therapy.

Gold nanoparticles immobilized on halloysite nanotubes for spatially-temporally localized photohyperthermia

Halloysite nanotubes (HNTs) with immobilized gold (Au) nanoparticles (NPs) were explored to enhance photoheating of aqueous media under excitation by continuous wave (CW) and nanosecond pulsed lasers with wavelengths close to the plasmonic resonance of Au-NPs. The structure and plasmonic properties of HNTs/Au-NP nanocomposites were analyzed by means of the transmission electron microscopy and optical spectroscopy. A remarkable photothermal effect with initial temperature growth of about 0.5 °C/min was observed for HNTs/Au-NPs’ aqueous suspension under relatively low excitation intensity, while the same photoexcitation of bare HNTs’ aqueous suspension did not result in any noticeable heating. In vitro experiments with Paramecium caudatum unicellular organisms have revealed a strong suppression of the cell viability after photoexcitation. While the average photoheating effect did not exceed 3–4 °C, the cell viability was decreased multifold, especially for the pulsed photoexcitation. The experimental results are explained by the spatially and temporally localized photohyperthermia in the vicinity of Au-NPs. The observed photoheating of HNTs/Au-NP nanocomposite is promising for applications in antibacterial treatment and targeted cancer therapy.

Composite pressure cell for pulsed magnets.

Extreme pressures and high magnetic fields can affect materials in profound and fascinating ways. However, large pressures and fields are often mutually incompatible; the rapidly changing fields provided by pulsed magnets induce eddy currents in the metallic components used in conventional pressure cells, causing serious heating, forces, and vibration. Here, we report a diamond-anvil-cell made mainly out of insulating composites that minimizes inductive heating while retaining sufficient strength to apply pressures of up to 8GPa. Any residual metallic component is made of low-conductivity metals and patterned to reduce eddy currents. The simple design enables rapid sample or pressure changes, desired by pulsed-magnetic-field-facility users. The pressure cell has been used in pulsed magnetic fields of up to 65T with no noticeable heating at cryogenic temperatures. Several measurement techniques are possible inside the cell at temperatures as low as 500 mK.

Is Solar Wind electron precipitation a source of neutral heating in the nightside Martian upper atmosphere?

Solar Wind (SW) electron precipitation is able to deposit a substantial amount of energy in the nightside Martian upper atmosphere, potentially exerting an influence on its thermal structure. This study serves as the first investigation of such an issue, with the aid of the simultaneous measurements of both neutral density and energetic electron intensity made on board the recent Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. We report that, from a statistical point of view, the existing measurements do not support a scenario of noticeable neutral heating via SW electron precipitation. However, during 3%−4% of the MAVEN orbits for which data are available, strong correlation between nightside temperature and electron intensity is observed, manifested as collocated enhancements in both parameters, as compared to the surrounding regions. In addition, our analysis also indicates that neutral heating via SW electron precipitation tends to be more effective at altitudes below 160 km for integrated electron intensities above 0.01 ergs·cm⁻²·s⁻¹ over the energy range of 3−450 eV. The results reported here highlight the necessity of incorporating SW electron precipitation as a heat source in the nightside Martian upper atmosphere under extreme circumstances such as during interplanetary coronal mass ejections.

Chemical and morphological changes in fibre structure due to material heating during ultrasonic-assisted embossing of cardboard

Embossing is a commonly used design element on printed products and packaging. It enhances the product impression with optical and haptic effects. The material deformation during the embossing of cardboard is normally done using high mechanical pressure between two dies. The use of ultrasound in the embossing process leads to a noticeable reduction of the embossing pressure and a greater embossing precision. However, there is a noticeable heating of the cardboard during the ultrasonic-assisted embossing process. This work aimed to characterise the effects of heating and to understand the reasons for the greater precision with decreased force when ultrasound is used. Therefore, the effects of the thermal ultrasonic energy on the chemical composition and the morphological properties of the fibres were investigated. The findings showed that no noticeable changes occurred in the chemical composition or fibre geometry as a result of the embossing process with ultrasound.

Thermal characterization of a single microdischarge in atmospheric pressure air dielectric barrier discharges

This work investigates the effect and mechanisms of gas heating in atmospheric pressure air dielectric barrier discharges with experimental measurements and numerical models developed. The heating sources of a single microdischarge (MD) are evaluated by the 1.5D plasma fluid model (PFM) with heating mechanisms including elastic collisions, the ionic Joule heating, and kinetics considered. A 3D gas flow model (GFM) simulating the temperature distribution of the reactor with the convective effect of airflow considered is developed to verify heating sources calculated by comparing the simulated gas temperature with the rotational temperature determined from N2 emission spectra measured. The source term of the energy equation in the 3D GFM is evaluated from the overall heating source calculated by the 1.5D PFM. The experimental average power consumption of the reactor is obtained and compiled statistically as 3.4 W. The average number of MDs in one cycle is compiled statistically as 140 MDs; therefore the average power consumption of a single MD obtained is around 0.024 W. The simulated power consumption of a single MD is around 0.028 W which agrees the average measured power consumption of a single MD. The heating sources of different mechanisms are evaluated by the 1.5D PFM and are provided as the average volumetric source term to the 3D GFM for evaluating the temperature distribution in the reactor. The simulated result shows that around 45% of power consumption is converted to thermal energy. The simulated average gas temperature at the center of the reactive zone is 460 K which agrees the rotational temperature determined as 470 K. Besides, both the simulated highest temperature and the temperature distribution of the reactor surface are close to those measured by the IR thermometer. The analysis of heating source finds that the ionic Joule heating and kinetics contribute to most of the heating source as 47% and 52%, respectively. Among the ionic species considered, plays the essential role and contributes to around 66% of the ionic Joule heating. Among the kinetics considered, exothermic processes contribute to most of the heating source as around 88%. Further analysis shows that the ozone generation and destruction reactions contribute to remarkable heating sources. The quenching processes of excited atomic oxygen and nitrogen species also contribute to noticeable heating sources and result in fast evolution of species densities. The N2(v) and O2(v) contribute to only a small percentage (∼10%) of the kinetic heating source under the operating conditions in this work.

Surgeon Survey Shows No Adverse Events With MRI in Patients With Magnetically Controlled Growing Rods (MCGRs)

Study DesignSurgeon survey. ObjectivesTo determine if magnetic resonance imaging (MRI) following implantation of magnetically controlled growing rods (MCGRs) is associated with any adverse events. Summary of Background DataMagnetically controlled growing rods have been shown to reduce the need for repeated surgical procedures and improve costs when compared to traditional growing rods, but concerns about MRI compatibility exist. MRIs are often clinically indicated in the EOS population. MethodsPediatric spine surgeons who are members of the Growing Spine Study Group, Children's Spine Study Group, and early international users of this technology were surveyed regarding MRI use after performing MCGR surgery. ResultsA total of 118 surgeons were surveyed. Four surgeons reported that 10 patients had an MRI with an implanted MCGR. Loss of fixation (0%, 0/10), movement of implants (0%, 0/10), unintended lengthening/shortening (0%, 0/10), or noticeable heating of MCGR (0%, 0/10) were not observed. No problems were observed with function of the MCGR following MRI, and a mean of 2.1 mm was obtained at the next lengthening (range, 0.5-3.0 mm). Two patients had brain MRIs, both of which could be interpreted. All cervical spine MRIs could be interpreted without excessive artifact (100%, 7/7). Six patients had MRIs of the thoracic or lumbar spine, but these were considered uninterpretable as a result of artifact from the MCGR device (0%, 0/6). ConclusionThese are the first reported cases of MRI use in humans with MCGR. There were no adverse events observed. MCGR rods lengthened as expected following MRI. MRIs of the brain and cervical spine were able to be interpreted, but MRIs of the thoracolumbar spine could not be interpreted because of MCGR artifact. MRIs can be safely performed in patients with MCGRs; however, MRIs of thoracic and thoracolumbar spine may be of limited clinical benefit because of artifact. Level of EvidenceLevel IV, case series.

Evaluation of the shape memory behavior of a poly(cyclooctene) based nanocomposite device

The objective of the present work is to investigate the electro‐activated shape memory behavior of a polycyclooctene (PCO) based nanocomposite device. At this aim, carbon black (CB) and exfoliated graphite nanoplatelets (xGnP) were melt compounded with a PCO matrix crosslinked with a dicumylperoxide content of 2 wt% and a total filler amount of 4 wt%. Electrical resistivity measurements on bulk materials evidenced a noticeable decrease of the electrical resistivity upon CB addition, while no synergistic effects were detected mixing CB and xGnP. Nanocomposite with a CB amount of 4 wt% revealed also a noticeable heating capability through Joule effect for voltage levels higher than 100 V. The subsequent characterization of an electro active shape memory device based on this composition demonstrated how it is possible to prepare a shape memory nanocomposite material able to completely recover its original shape after 100 s with a voltage of 90 V. The retention of the shape memory behavior after several (50) programming cycles was also demonstrated. POLYM. ENG. SCI., 58:430–437, 2018. © 2017 Society of Plastics Engineers

Thermal Effect during Electromagnetic Pulse Welding Process

Magnetic pulse welding (MPW) is a solid state joining process, successfully utilized to join dissimilar metals. This advantage attracted manufacturing industries to fabricate hybrid materials to attain materials with a combination of multiple attributes. The high speed impact during the welding process causes various interfacial phenomena, which have been reported in previous research studies. Combined high speed collision, Joule heating due to eddy current and plastic heat dissipation cause noticeable heating in the workpiece. The heating from the plastic work and collision energy could particularly be significant at the vicinity of the interface compared to other regions of the workpiece. The Joule heating due to eddy current affects the entire workpiece that is prominent before the collision. There is a sharp increase of the temperature at the onset of weld formation due to dissipation of plastic work during the collision. 3D simulations of coupled electromagnetic-mechanical-thermal were carried out to investigate the heating due to the combined Joule heating and plastic dissipation. A case study of MPW, consist of a one turn coil combined with a field shaper, is used to investigate the welding process. The simulations were performed using LS-DYNA®, which has the capability of using both finite and boundary elements to solve the thermo-mechanical problem during electromagnetic forming. The predicted temperature distributions from numerical simulations show expected phenomena of Joule heating and plastic heat dissipation while the analytical approach used to estimate the localized increase in temperature due to supersonic gaseous compression. Minimizing the heating effect by identifying the influencing factors could help to optimize and control the quality of the magnetic pulse welded parts.

Safe Discharge of Damaged Li-Ion Batteries with Redox-Shuttle Additives

Due to continuous research and development efforts, the intrinsic safety of Li-ion batteries (LIBs) has increased significantly over the last years. A critical issue to resolve remains the question what to do with damaged LIBs in the charged state. Batteries can contain protection mechanisms, the activation of which may result in situations where the battery cannot be electrically discharged any longer. This contribution presents a safe way of discharging batteries at a cell level using water, aqueous salt solutions, or organic solutions of redox-shuttle additives as discharge agents. The discharge solutions can be added to the cell from the outside when discharge is required, or, in case they are already contained in the cell, they can be activated by adequate technical trigger mechanisms. A number of examples of compounds is shown and compared for 20 Ah prismatic Li-ion cells. Typical discharge times are in the range of 30 to 60 hours (shorter times are expected for higher concentrations of the discharge agents than tested here). The end-of-discharge voltage is typically between 0 and 1 V, depending on the respective discharge agent. Discharge with water and aqueous solutions is the cheapest way of discharge, but since it is accompanied by gas evolution, it may cause secondary risks via the evolved gas. The organic solutions of redox-shuttle additives enable a complete discharge without any gas evolution, and are thus the safer option (cf. Figure: Evolution of cell voltage after addition of redox-shuttle additives). During discharge the chemical energy contained in the charged cell is converted into thermal energy. For the timescale of the given experiment, however, no noticeable heating of the cell was observed (with the temperature changes remaining < 3 °C, which was within the natural variation of the ambient temperature). The underlying discharge reaction mechanisms are explained and requirements and limitations for the discharge agents are discussed. Acknowledgement: Financial support of parts of this work from the German Association of the Automotive Industry (VDA) is gratefully acknowledged. Figure 1

Impact of Heterostructure Design on Transport Properties in the Second Landau Level ofIn SituBack-Gated Two-Dimensional Electron Gases

We report on transport in the second Landau level in \emph{in-situ} back-gated two-dimensional electron gases in GaAs/Al$_x$Ga$_{1-x}$As quantum wells. Minimization of gate leakage is the primary heterostructure design consideration. Leakage currents resulting in dissipation as small as $\sim$ 10 pW can cause noticeable heating of the electrons at 10 mK, limiting the formation of novel correlated states. We show that when the heterostructure design is properly optimized, gate voltages as large as 4V can be applied with negligible gate leakage, allowing the density to be tuned over a large range from depletion to over 4 $\times$ 10$^{11}$ cm$^{-2}$. As a result, the strength of the $\nu = 5/2$ state can be continuously tuned from onset at n $\sim 1.2 \times 10^{11}$ cm$^{-2}$ to a maximum $\Delta_{5/2} = 625$ mK at n = $3.35 \times 10^{11}$ cm$^{-2}$. An unusual evolution of the reentrant integer quantum Hall states as a function of density is also reported. These devices can be expected to be useful in experiments aimed at proving the existence of non-Abelian phases useful for topological quantum computation.

Experimental investigation and industrial application of Ranque-Hilsch vortex tube

Despite long period of study, Ranque effect remains unexplored in natural gas industry. There is a lack of industrial operation data. No information was found about achieving high temperatures due to Ranque effect on natural gas plants. In present experimental research, temperature separation in high pressure natural gas stream within a counter flow vortex tube was investigated. An industrial vortex tube was designed and implemented into low-temperature separation plant. It was found that Joule-Thomson effect has significant influence on temperature separation process and should be taken into account when analyzing operation data. Noticeable heating effect under investigated conditions could be seen only at very small hot stream mass fractions. To avoid liquid loading problems free gas condensate and water should be removed before the vortex tube or directly from its body. The increase of pressure ratio leads to higher temperature differences. Cold stream temperature drop is higher than Joule-Thomson effect on almost all range of cold stream mass fractions. The ejecting type of flow was achieved in experiments that causes the reduction of Ranque effect efficiency. However, such flow could also be useful for utilization of flashed petroleum gases.

Optical mapping at increased illumination intensities

Voltage-sensitive fluorescent dyes have become a major tool in cardiac and neuro-electrophysiology. Achieving high signal-to-noise ratios requires increased illumination intensities, which may cause photobleaching and phototoxicity. The optimal range of illumination intensities varies for different dyes and must be evaluated individually. We evaluate two dyes: di-4-ANBDQBS (excitation 660 nm) and di-4-ANEPPS (excitation 532 nm) in the guinea pig heart. The light intensity varies from 0.1 to 5 mW/mm2, with the upper limit at 5 to 10 times above values reported in the literature. The duration of illumination was 60 s, which in guinea pigs corresponds to 300 beats at a normal heart rate. Within the identified duration and intensity range, neither dye shows significant photobleaching or detectable phototoxic effects. However, light absorption at higher intensities causes noticeable tissue heating, which affects the electrophysiological parameters. The most pronounced effect is a shortening of the action potential duration, which, in the case of 532-nm excitation, can reach ∼30%. At 660-nm excitation, the effect is ∼10%. These findings may have important implications for the design of optical mapping protocols in biomedical applications.

Ion dynamics at supercritical quasi-parallel shocks: Hybrid simulations

By separating the incident ions into directly transmitted, downstream thermalized, and diffuse ions, we perform one-dimensional (1D) hybrid simulations to investigate ion dynamics at a supercritical quasi-parallel shock. In the simulations, the angle between the upstream magnetic field and shock nominal direction is θBn=30°, and the Alfven Mach number is MA∼5.5. The shock exhibits a periodic reformation process. The ion reflection occurs at the beginning of the reformation cycle. Part of the reflected ions is trapped between the old and new shock fronts for an extended time period. These particles eventually form superthermal diffuse ions after they escape to the upstream of the new shock front at the end of the reformation cycle. The other reflected ions may return to the shock immediately or be trapped between the old and new shock fronts for a short time period. When the amplitude of the new shock front exceeds that of the old shock front and the reformation cycle is finished, these ions become thermalized ions in the downstream. No noticeable heating can be found in the directly transmitted ions. The relevance of our simulations to the satellite observations is also discussed in the paper.

Phase transitions, intermolecular interactions and electrical conductivity behavior in carbon multiwalled nanotubes/nematic liquid crystal composites

The phase transitions, intermolecular interactions and electrical percolation behavior in the composites of multiwalled carbon nanotubes (MWNTs) and nematic LC ( p-ethoxybenzylidene- p′-butylaniline, EBBA) are experimentally investigated in this work. The concentration of nanotubes was between 0 and 1% (wt), and the temperature interval was 273–363 K. The experimental data of differential scanning calorimetry (DSC) and FTIR adsorption spectra evidence the presence of strong interactions inside MWNTs/EBBA nanocomposites. An increase of both isotropic-to-nematic (by 0.5-1 K) and nematic-to-crystalline (by 1.5-3 K) phase transition temperatures was observed for EBBA filled with MWNTs. The FTIR spectroscopic data evidence an enhancement of the strong binding interaction between MWNTs and EBBA with increase of the concentration of MWNTs. It was shown that intermolecular interactions affect noticeably the electrical conductivity of MWNTs/EBBA composites. The percolation transition from non-conductive to high conductive state, and the effect of positive temperature coefficient (PTC effect) were observed at MWNT concentrations exceeding 0.05-0.1 wt.% Within the nematic phase temperature range, the electrical conductivity of the composites reveals a noticeable heating–cooling hysteresis and follows Arrhenius behavior. The activation energy decreases when MWNTs concentration increases, which supports the dominating role of the junction mechanism related to the thermal motion of nanotubes. The electric field dependence of the electrical conductivity was explained by the existence of the field-enhanced charge transport through hopping junctions in the LC gaps.

The turbulence in free shear flows and in accretion discs

Physical models of the development of turbulence in free shear flows and in accretion discs are proposed. The models are based on the results of numerical simulations of turbulent flow development. The main idea of the proposed theory of turbulence in free shear flow is stated as follows: the onset of turbulence begins with the formation of large vortices. The formation and evolution of large-scale turbulence in accretion discs are considered. It is shown that the kinetic energy of vortices forming in a turbulent flow is a virtually constant fraction of the initial kinetic energy of the rotating matter of an accretion disc. A possible mechanism explaining the transfer of angular momentum by large vortices that form in the disc without any noticeable heating of the matter is suggested.

Spin-bottleneck due to spin-charge separation in a superconductor

An experimental device was designed to measure the effect of the injection of spin-polarized carriers on the superconductive gap and density of states (DOS). Quasiparticles were injected from a ferromagnet $({\mathrm{Ni}}_{0.8}{\mathrm{Fe}}_{0.2})$ through a tunnel junction into a conventional superconductor (Nb), while charge neutrality was maintained by a supercurrent. The DOS of the superconductor was measured through a second tunnel junction with a normal paramagnetic metal. No significant decrease of the superconductive gap was observed while a noticeable heating of the quasiparticles of the superconductor was measured. A similar experiment performed with current injected from a paramagnet (Al or Ag) showed no heating of quasiparticles. These observations are consistent with spin-charge separation of Bogoliubov quasiparticles and spin-bottleneck due to the enhanced recombination time of pure spin excitations.

Micro-Raman investigation of optical phonons in ZnO nanocrystals

We have measured nonresonant and resonant Raman-scattering spectra from ZnO nanocrystals with an average diameter of 20nm. Based on our experimental data and comparison with the recently developed theory, we show that the observed shifts of the polar optical-phonon peaks in the resonant Raman spectra are not related to the spatial phonon confinement. The very weak dispersion of the polar optical phonons in ZnO nanocrystals does not lead to any noticeable redshift of the phonon peaks for 20-nm nanocrystals. The observed phonon shifts have been attributed to the local heating effects. We have demonstrated that even the low-power ultraviolet laser excitation, required for the resonant Raman spectroscopy, can lead to the strong local heating of ZnO nanocrystals. The latter causes significant (up to 14cm−1) redshift of the optical-phonon peaks compared to their position in bulk crystals. Nonresonant Raman excitation does not produce noticeable local heating. The obtained results can be used for identification of the phonons in the Raman spectra of ZnO nanostructures.

A high current density DC magnetohydrodynamic (MHD) micropump

This paper describes the working principle of a DC magnetohydrodynamic (MHD) micropump that can be operated at high DC current densities (J) in 75-microm-deep microfluidic channels without introducing gas bubbles into the pumping channel. The main design feature for current generation is a micromachined frit-like structure that connects the pumping channel to side reservoirs, where platinum electrodes are located. Current densities up to 4000 A m(-2) could be obtained without noticeable Joule heating in the system. The pump performance was studied as a function of current density and magnetic field intensity, as well as buffer ionic strength and pH. Bead velocities of up to 1 mm s(-1) (0.5 microL min(-1)) were observed in buffered solutions using a 0.4 T NdFeB permanent magnet, at an applied current density of 4000 A m(-2). This pump is intended for transport of electrolyte solutions having a relatively high ionic strength (0.5-1 M) in a DC magnetic field environment. The application of this pump for the study of biological samples in a miniaturized total analysis system (microTAS) with integrated NMR detection is foreseen. In the 7 T NMR environment, a minimum 16-fold increase in volumetric flow rate for a given applied current density is expected.