Bath Temperature Research Articles

Implementation of instantaneous comparison methods in temperature gradient evaluation of stirred liquid temperature baths

Temperature gradient is an important performance indicator of a stirred liquid bath. Its evaluation requires measuring the temperature differences between different bath positions. A common way to do that is to place two SPRTs at two positions and measure their resistances against a standard resistor (R SPRT1/R S and R SPRT2/R S) sequentially (the sequential method). A drawback of this method is the existence of a time gap between the two measurements rendering the results susceptible to temporal temperature variation. The instantaneous comparisons method offers a better solution by measuring the resistance ratio of two SPRTs directly (R SPRT1/R SPRT2) and deriving their temperature difference at the same moment eliminating the time gap. To implement this method at the Standards and Calibration Laboratory (SCL) of Hong Kong, the resistance ratio of SPRT1 to a standard resistor (R SPRT1/R s) is firstly measured to determine the initial bath temperature. After that, the resistance ratios of SPRT1 to SPRT2 (R SPRT1/R SPRT2) are measured with the two SPRTs placed at different positions and immersion depths in the bath. This paper describes the derivation of the temperature difference from the SPRT resistance ratio using the ITS-90 reference equations and the estimation of the measurement uncertainties. The potential of reducing the uncertainties of measured temperature gradient by leveraging the correlation of the two SPRTs calibrated at the same set of temperature fixed points is discussed. The paper also compares the calibration results obtained by the instantaneous comparisons method and the sequential method.

Growth process and mechanism of hot-dip galvanised Zn–5Al coating on steel

ABSTRACT In this paper, the growth process and mechanism of hot-dip galvanised Zn–5Al coating on steel at different bath temperatures and immersion times were investigated by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The result shows that the growth of Zn–5Al coating is approximately divided into three stages: initial incubation stage, rapid thickening stage and steady detaching stage. The thickening and outbreak of the intermetallic layer is responsible for the thickening of the coating. When immersed into the Zn–Al bath, an Fe–Al intermetallic layer forms on the interface of liquid and steel and prevents the coating growing at the initial time; with the immersion time increasing, the solid-soluble Zn in the Fe–Al intermetallic layer makes the intermetallic layer unstable, the liquid Zn is discharged outward from the intermetallic layer and many pores and cracks occur, making the coating growth enter the rapid thickening stage. As the liquid phase areas keep expanding, the intermetallic layer will start to detach outward and produce a large amount of dross, the coating with linear growth finally enters the steady detaching stage. Increasing the immersion temperature will accelerate the growing rate of the coating and shorten the initial incubation stage of the coating.

Stable method for electrodepositing network-like magnesium hydroxide layer with superhydrophobicity and enhanced surface performance under structure direction of xanthan gum/glycerol

Investigation of magnesium hydroxide superhydrophobic layer would significantly improve the application of green and low-cost superhydrophobic materials, for the abundant source, low economic cost, nontoxicity and environment friendliness of magnesium hydroxide. In this work, an obviously developed method which is stable and easy for fabricating network-like magnesium hydroxide superhydrophobic layer on iron substrate has been rendered, simply by cathodic electrodeposition with magnesium nitrate aqueous solution under structure direction of glycerin cross-linked xanthan gum, and subsequent surface modification with 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The preparation process could be carried out at tremendously wide range of bath temperature (from 15 °C to 75 °C), xanthan gum/glycerol dissolving temperature (from room temperature to 100 °C), and storage times (from 0 day to 30 days). The superhydrophobic layer obtained at 35 °C bath temperature with addition of xanthan gum/glycerol dissolved at room temperature and stored for 7 days, shows strong water repellency (160.1° water contact angle, 3.2° sliding angle), and excellent self-cleaning performance. The layer also demonstrates good mechanical property according to cross hatch adhesion and tape peeling test, and owns an inhibition current efficiency as high as 99.98%, taking advantage of its extremely high anti-corrosion resistance (Rct = 2.87 × 105 Ω cm−2, Rf = 1.49 × 109 Ω cm−2).

Constraint on the chemical potentials of hydrogen and proton in recombination

In this paper, we revisit the hydrogen recombination history from a novel perspective: the evolution of chemical potentials. We derive expressions for the chemical potentials, which depend on the thermal bath temperature and the ionization degree of the universe. Our main finding reveals a constraint between the chemical potentials of hydrogen and proton at zapprox 1200 when the free electron fraction is X_eapprox 1/3. Furthermore, we present important data on the chemical potentials during recombination, highlighting the differences between the predictions of the Peebles’ and CosmoRec code solutions. Finally, we discuss a particular case related to the chemical potential of hydrogen.

Performance of chemically synthesized polyaniline film based asymmetric supercapacitor: Effect of reaction bath temperature

Performance of chemically synthesized polyaniline film based asymmetric supercapacitor: Effect of reaction bath temperature

Characterization of local non-equilibrium phonons in bulk MoS2 probed by temperature-dependent Raman scattering

This study presents an experimental implementation to determine the temperature dependence of Raman spectra of bulk 2H-MoS2 in the temperature range of 300–650 K. In addition, we have measured according to the anti-Stokes to Stokes integrated intensity ratio (). The results indicate that Raman shift of both the vibration modes and exhibits a linear temperature-dependent behavior in the heating and cooling processes. It is confirmed that the sample did not deteriorate by oxidization and decomposition at high temperatures. However, above 500 K, the measured phonon temperature deviated from the heat bath temperature. It is suggested that the does not correspond to the equilibrium population of optical phonons, thus indicating that the measurement was not in thermal equilibrium but in a thermal steady state under laser irradiation. We conclude that this is caused by the difference in relaxation times in the thermal steady state.

Refining at the impact and emulsion zones of basic oxygen steel making process – a fundamental study

ABSTRACT Insights into the kinetics occurring during the combined blown (top and bottom blowing) oxygen steelmaking process, particularly at the impact and emulsion zones within separate reactors, can provide a deeper understanding of the refining mechanism in steelmaking. A dynamic model has been developed that can predict the contributions of various refining processes such as decarburization, desiliconization, demanganization, and dephosphorization. The model considers gas–metal interactions at the impact zone and slag–metal–gas interactions at the emulsion zone in an oxygen steelmaking converter. The model includes sub-models for lime dissolution and heat loss calculation. FactSage™ software and its macro programming facility were employed to integrate thermochemical and kinetic information into the model. The model predicts the temperature, composition, and volume of several phases involved in the process. The model predictions transient metal and slag compositions and metal bath temperature, were found to be consistent with the plant data.

Quenching with Aqueous Polymer Solutions

Abstract Quenching with aqueous polymer solutions has some distinct advantages over classical oil quenching. Among these are the good environmental properties and the possibility to adjust the quenching performance between oil and water quenching. Nevertheless, critical aspects must also be taken into account. When quenching steel parts with polymer solutions, “explosion-like” phenomena can occur, often accompanied by large cooling rate changes. These “explosions” can lead to pressure waves and vibrations in the quenching tank, which in the long run can even destroy weld seams of the quenching tank. In the framework of a research project, experimental investigations were carried out in a laboratory quenching bath and in an industrial quenching tank. The polymer type, the type of incident flow, the flow velocity, the bath temperature and the size of the test shafts were varied. Near-surface temperature measurements inside the shafts were performed to characterize the resulting quenching processes. Simultaneously, electrical conductivity measurements and audio and video recordings were made to localize insulating films on the surface and their collapse. To systematize and characterize the large number of measurement results, characteristic types of cooling processes and characteristic numbers for their characterization were defined and will be presented in this paper.

Thermal Fisher and Wigner–Yanase information correlations in two-qubit Heisenberg XYZ chain

Using Wigner–Yanase and Fisher information [including local quantum uncertainty (LQU) and local quantum Fisher information (LQFI)] as well as log-negativity, we investigate the thermal non-local correlations of two-qubit Heisenberg XYZ non-X states produced in the presence of the Dzyaloshinskii–Moriya (DM) interaction. The two-spin XYZ-Heisenberg non-local correlation decay can be weakened by increasing the DM interaction as well as the spin–spin XYZ-Heisenberg interactions. The LQFI correlation has greater resistance to thermal degradation. The spin–spin y-component antiferromagnetic coupling has a higher ability to protect the generated spin–spin nonlocal correlations against high temperatures. The emergence of the phenomena of the sudden death of log-negativity and the sudden change of the LQFI and LQU depend on the spin–spin XYZ-Heisenberg and DM interactions as well as on the bath temperature. The generated asymmetric correlations resulting due to the x,y-component spin interactions confirm that the antiferromagnetic coupling has a high ability to generate a maximally correlated two-qubit state. While the generated correlations, due to two-spin z-component interaction, present symmetric dynamics, and its amount depends on the x-component spin interaction.

Effect of heating temperature on electrical properties and gel properties of carp surimi

AbstractFor better application of ohmic heating technology in the food industry, it is necessary to study the variation of the electrical properties of food materials with temperature. In this paper, various initial heating temperatures were applied to investigate the impact of temperature on the electrical properties of rinsed and unrinsed carp surimi. An impedance analyzer was utilized to measure the electrical parameters of carp surimi within the frequency range of 20 ~ 120 MHz. The frequency and temperature characteristics of electrical parameters were explained based on biological and electromagnetic theories. These findings furnish theoretical references and experimental evidence for applying ohmic heating technology. The results showed that the parallel inductance (Lp), parallel capacitance (Cp), parallel resistance (Rp), and impedance (Z) of surimi decreased as the internal temperature of the surimi increased. The greater the heating temperature of the water bath, the larger the parameter values. The Lp, Cp, Rp, and Z values were lower for unrinsed surimi than for rinsed surimi. During the heating and cooling process, the parameter values at the same temperature point differed due to the different states of the surimi gel. As the frequency increased, the Rp and Z of surimi showed different regular changes, with similar trends at the same temperature. Rinsing has been demonstrated to improve the gel properties of surimi effectively. Prolonged periods in the temperature range of 60 ~ 70°C can cause the modori phenomenon (gel degradation), leading to reduce the gel strength of surimi. Thus, it is essential to pass through this temperature zone as soon as possible during the preparation of surimi gel. The relationship between the internal microstructure of surimi gel and the electrical parameters needs to be further investigated.Practical ApplicationsAs an emerging technology for food heat treatment, ohmic heating has the characteristics of uniform heating and fast heat production. As a homogeneous material, surimi is ideal for ohmic heating. However, the heating process is not easy to control when the electrical parameters are unknown, so the purpose of this study is to explore the changes of the electrical parameters of surimi at different heating rates and temperatures, provide data reference for the heat treatment of surimi by ohmic heating, and promote the application of ohmic heating in surimi processing.

Thermal radiation in asymmetrically driven coupled non-linear photonic cavities

We study thermal radiation from a system of two coupled photonic cavities including the nonlinear Kerr effect, using numerical simulations and analytical methods. The general system, which can be implemented as two cavities in a waveguide, is asymmetrically driven with a monochromatic pumping from a single side. We describe the eigenmodes in the linear and nonlinear regime as well as the transmission of the coupled system. These results are then employed to understand the thermal radiation exhibited from both sides as each part of the system is coupled to a bath at a different temperature. Interestingly, the radiation spectrum is complicated, and can present up to four peaks due to the rich nonlinear coupling features. Furthermore, in certain regimes these spectra can drastically change upon variation of the bath temperatures. In addition, interference between the emitted and reflected radiation can lead to dips in the thermal radiation. Moreover, the system can exhibit self-pulsing, leading to comblike spectra for thermal radiation with peaks of very large amplitude. Our proposed analytical model for thermal radiation in the stable regime fits very well with the numerical results and describes a general class of devices.

Photon-counting with single stoichiometric TiN layer-based optical MKIDs

We demonstrate the single photon counting mode at 405 and 850 nm with stoichiometric TiN-based microwave kinetic inductance detectors realized on a sapphire substrate and operated at bath temperatures over 300 mK. The detectors use single 15–25 nm-thick TiN layers featuring a critical temperature in the 2–3 K range. We found that the energy-resolving power R=E/ΔE exhibits an optimum with bath temperature, occurring in the 300–450 mK range, which can be almost double compared to those obtained at the lowest temperatures. Furthermore, the single photon regime is observed up to 700 mK. In addition to a high-temperature operation, the single stoichiometric layer would allow achieving a better uniformity in the critical temperature and, thus, kinetic inductance, compared to the often desired ∼1 K sub-stoichiometric TiN.

Property evaluation of magnesia-based cement emulsified asphalt mortar (MCAM) as pavement repair material

ABSTRACT In order to meet the requirements of compatibility and timeliness of repair materials for asphalt pavement, a rapid-hardening magnesia-based cement emulsified asphalt mortar (MCAM) is prepared. The results show that high temperature or high-temperature water bath treatment reduces the stability of MCAM, and MCAM prepared from emulsified asphalt with high softening point and low water content has better high-temperature stability. Increasing the asphalt-cement (A/C) ratio decreases the dynamic stability and stiffness modulus of the MCAM-repaired asphalt mixture, but increases its failure strain, which is determined by the material properties of the asphalt and cement phases. The splitting tensile strength of MCAM-asphalt mixture specimens are all above 0.8 MPa, and the strength ratio before and after freezing and thawing is above 90%, which is significantly higher than that of traditional asphalt-based, epoxy-based and polyurethane-based pavement repair materials. When MCAM is used to repair dried surface of asphalt mixtures, its pull-out bonded strength is significantly higher than that after wet and aged treatments. In addition, the microstructure of MCAM also shows that the asphalt phase and the cement phase are mixed together, and the microstructure becomes loose as the A/C ratio increases.

Investigation of copper corrosion behavior in chloride bath for nickel electrodeposition

The present study is devoted to the electrodeposition of nickel layers on copper substrates by cyclic voltammetry from chloride bath at a scan rate of 20 mV/s and at different bath temperatures between 25 and 55 °C and then after to their corrosion behavior in chloride bath. The electrochemical behavior and corrosion properties were evaluated by cyclic voltammetry, potentiodynamic and electrochemical impedance spectroscopy. While the surface analysis of nickel coating at different temperatures was conducted by optical microscopy and white light interferometer (WLI). The obtained results show that the Ni layers have been deposited successfully on the Cu substrates. It was found that raising the bath temperature to 55 °C leads to smoother, dense, compact and recovering Ni coatings with a grain size of 0.024 nm and 0.294 µm as average roughness, which is mainly due to Ni grain refinement. While the effect of increasing bath temperature leads to a decrease in the corrosion resistance of copper.

Influence of Deposition Parameters for Cu2O and CuO Thin Films by Electrodeposition Technique: A Short Review

The transition metal oxide-based nanomaterial attracted researchers for its various applications due to its interesting physical, chemical, and optical properties. Copper oxide thin films with different oxidation states were prepared on various transparent, nontransparent nature conducting substrates from the acidic and alkaline medium by electrodeposition technique. The deposition parameters such as potential, bath temperature, solution pH, and deposition time determine the physical, chemical, and optical properties. The complexing agents such as sodium thiosulfate, lactic acid, citric acid, and triethanolamine determine the stability of cuprous and cupric ions in the deposited films. Optical properties reported that the deposited films have direct band gap value 1.3 and 3.7 eV represents the absorbance of the deposited films in the visible region of solar spectrum. The absorbance of light in visible region, good electrical conductivity, and various nanostructure morphologies with the environment-friendly constituents are the distinctive properties of copper metal oxides.

Effect of Classical and Quantum Superposition of Atomic States on Quantum Correlations

In this paper, we report the effect of classical and quantum superposition of atomic states on quantum correlations. Coupled photon pairs generated in a ladder quantum beat laser using coherent-induced classical field and atomic state coherent superposition are considered. Once the quantum coherence get sufficient time, it can generate quantum correlations that include quantum discord, quantum entanglement, and quantum steering, which quickly increase with time until they get their maximum strength. Their strength can be improved further by increasing the number of superposed atoms per unit time, selecting an appropriate amplitude of the classical fields, and managing the amount of temperatures and phase fluctuations. In particular, two-way quantum steering, which is a guarantee for the existence of quantum discord and quantum entanglement, can be achieved by increasing the rate of atomic injection from 2 kHz to 25 kHz even if the mean temperature of the heat bath is considered. The maximum achievable strength of quantum correlations is enhanced by increasing the rate of atomic injection and choosing an appropriate parameters of the coherent-induced classical field in the open quantum system which is treated by using the density operator approach.

Nanostructured membranes with interconnected pores via a combination of phase inversion and solvent crystallisation approach

Polyethersulfone (PES) is an important membrane material in wastewater and medical applications due to its outstanding thermal and mechanical properties. However, when processing the PES into the asymmetric membranes through nonsolvent-induced phase separation (NIPS) method, the emergence of macro voids and discrete porosities has hampered its permeation performance. In this study, we present a novel phase inversion and solvent crystallisation approach that combines NIPS with the combined crystallisation and diffusion (CCD) technique, named as (NIPS-CCD) to significantly improve PES ultrafiltration membrane permeation without use of any additives. The NIPS-CCD method is simple and requires only a change in casting plate material and water bath temperature. The resultant membrane features a typical NIPS-like skin layer and elongated finger like structure, which are integrally connected to aligned microchannels formed through the CCD technique. With the enhanced pore connectivity, a 50-fold increase in water permeation up to 771 LMH bar−1 was obtained from the NIPS-CCD membrane with the pore size of 6–7 nm. This approach can be easily adapted to industrial production for other high-performance membrane materials with a minimal process modification, making it a promising strategy for improving the permeation properties of membranes used in various applications.

The influence of ultrasound-assisted osmotic dehydration as a pre-treatment method on the quality of vacuum dried pineapple

This study investigated the effect of ultrasound-assisted osmotic dehydration (UAOD) as a pre-treatment before vacuum drying on the drying time, quality, and microstructure of pineapple. At first, the best conditions for water desorption during osmotic dehydration (OD) were optimized. Pineapple cubes were subjected to OD at different osmotic solution concentrations (30, 40, and 60°Brix), pre-treatment time (0.5 and 1 hr), and temperature (35ºC) using two types of osmotic agents (sucrose and fructose). According to the results, sucrose was the best osmotic agent because it reduced the sample's moisture content and water activity. Secondly, the influence of UAOD on sugar gain, water loss, and drying time was evaluated using sucrose as an osmotic agent. Pineapple cubes were subjected to UAOD at different osmotic solution concentrations (30 and 60°Brix), pre-treatment time (10, 20, and 30 mint), and temperature (40 ºC) in an ultrasonic bath (ultrasound frequency of 40 kHz and ultrasound power of 300 W). Results exhibited that the application of UAOD increased the sugar gain and water loss, consequently decreasing the drying time. Overall, a 15.31 % reduction in vacuum drying time on a self-designed vacuum dryer and a 9 % reduction in total processing time were observed when UAOD (30 ºBrix) was applied for 20 min. Moreover, the influence of UAOD on the quality of dried pineapple in terms of rehydration ratio, firmness, and color change was also determined. Results showed that the pre-treatment with UAOD (30 ºBrix) of 20 min provided a better rehydration ability, with minimum change in color and textural properties. However, an increase in the pre-treatment time beyond 20 min diminished the rehydration ability of the dried product. Scanning electron microscope (SEM) images of pretreated and dried pineapples were also analyzed to determine the effect of pre-treatments applied for different lengths of time on the microstructure of the pineapple. The study's results suggested that applying UAOD as a pre-treatment considerably reduced the processing time and better retention of the pineapple properties.

Universal Subdiffusive Behavior at Band Edges from Transfer Matrix Exceptional Points.

We discover a deep connection between parity-time symmetric optical systems and quantum transport in one-dimensional fermionic chains in a two-terminal open system setting. The spectrum of one dimensional tight-binding chain with periodic on-site potential can be obtained by casting the problem in terms of 2×2 transfer matrices. We find that these non-Hermitian matrices have a symmetry exactly analogous to the parity-time symmetry of balanced-gain-loss optical systems, and hence show analogous transitions across exceptional points. We show that the exceptional points of the transfer matrix of a unit cell correspond to the band edges of the spectrum. When connected to two zero temperature baths at two ends, this consequently leads to subdiffusive scaling of conductance with system size, with an exponent 2, if the chemical potential of the baths are equal to the band edges. We further demonstrate the existence of a dissipative quantum phase transition as the chemical potential is tuned across any band edge. Remarkably, this feature is analogous to transition across a mobility edge in quasiperiodic systems. This behavior is universal, irrespective of the details of the periodic potential and the number of bands of the underlying lattice. It, however, has no analog in absence of the baths.

Central Basis For MDMA (ecstasy) Induced Hyponatremia

Clinical studies have shown that hyponatremia can be induced by the ingestion of the recreational drug MDMA (3,4-Methyl​enedioxy​methamphetamine, ecstasy) when combined with a water intake (Baggot et al., 2016). However, the mechanisms by which MDMA induces hyponatremia is unknown. Hyponatremia is a life-threatening condition that causes rapid swelling of the brain and is commonly encountered in critical care medicine (emergency) (Woods et al., 1993 & Kirch, Bigelow, Weinberger, 1985). Under the Controlled Drugs and Substances Act (CDSA), MDMA is a schedule 1 drug (illegal) and consumption usually occurs at dance parties or raves. Nonetheless, despite MDMA’s scheduling, the Multidisciplinary Association for Psychedelic Studies (MAPS) has headed the movement toward using MDMA for assisted psychotherapy for PTSD (Sessa, Higbed, & Nutt, 2019). In summary, with a prevalence of 3.5% of young adults 18-25 years old using MDMA in the United States in 2014 (Betzler, Viohl, & Romanczuk-Seiferth, 2017), along with the mainstream marketing of MDMA for PTSD, combined with very serious and potentially deathly side effects makes this substance worthwhile to investigate. Findings could not only aid in MDMA associated hyponatremia but could also provide the foundation clinically for fluid regulation during MDMA assisted psychotherapy. Clinically, ingestion of MDMA has been shown to cause an increase in the hormones vasopressin and oxytocin (Wolf et al., 2006). Therefore, we examined cFos activity in male rats, we show that there is an increase in both cFos activation of vasopressin as well as oxytocin neurons of the supra optic nucleus. Next, we wanted to test the notion that MDMA causes an increase in thirst. Our data shows that an injection of MDMA does not increase drinking behavior. Combatting the conventional thinking that MDMA causes an increase in thirst. Interestingly, in line with the human literature, when you combine MDMA with a gastric water load, it is sufficient to drop serum sodium levels to hyponatremic levels i.e. <135mmol/L. Indicating that a water load combined with MDMA is necessary for MDMA induced hyponatremia. Conventionally, MDMA has been shown to increase the amount of serotonin within the synaptic cleft, via the inhibition of uptake via the serotonin transporter (Oeri, 2021). To determine if MDMA is working via the release of 5HT in a temperature-controlled environment we utilized whole cell patch clamp slice electrophysiology of male double transgenic Wistar rats enabling fluorescent identification of vasopressin and oxytocin neurons. Interestingly, at a bath temperature of a constant 30°C, a bath application of 5HT was sufficient in causing an enhancement of action potential firing, and this could be blocked by a 5HT receptor antagonist. Moreover, a bath application of MDMA also caused an increase in action potential firing, which too could be blocked by a 5HT receptor antagonist. CIHR. HBHL, McGill Faculty of Medicine This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.