Temperature Region Research Articles

Selective Segregation of Thermo-Responsive Microgels via Microfluidic Technology.

Separation of equally sized particles distinguished solely by material properties remains still a very challenging task. Here a simple separation of differently charged, thermo-responsive polymeric particles (for example microgels) but equal in size, via the combination of pressure-driven microfluidic flow and precise temperature control is proposed. The separation principle relies on forcing thermo-responsive microgels to undergo the volume phase transition during heating and therefore changing its size and correspondingly the change in drift along a pressure driven shear flow. Different thermo-responsive particle types such as different grades of ionizable groups inside the polymer matrix have different temperature regions of volume phase transition temperature (VPTT). This enables selective control of collapsed versus swollen microgels, and accordingly, this physical principle provides a simple method for fractioning a binary mixture with at least one thermo-responsive particle, which is achieved by elution times in the sense of particle chromatography. The concepts are visualized in experimental studies, with an intend to improve the purification strategy of the broad distribution of charged microgels into fractioning to more narrow distribution microgels distinguished solely by slight differences in net charge.

SrTiO3 doped KLBBNT ceramics with wide dielectric temperature stable range and high permittivity

(1-x)K0.05La0.05Ba0.054(Bi0.5Na0.5)0.846Ti0.95Cr0.025Nb0.025O3-xSrTiO3 ceramics (abbreviated as (1-x)KLBBNT-xST, x=0.05, 0.1, 0.15, 0.2) were fabricated using solid state reaction method. The ceramic sample with x=0.05 demonstrates outstanding temperature stability of dielectric properties, achieving a maximum permittivity (εrmax) of approximately 3420. The temperature coefficient of capacitance (TCC) of x=0.05 ceramics remains within −15 %≤TCC≤15 % over the temperature range of 54–308 ℃. Analysis of the phase structure and ε-temperature graphs suggests that the outstanding dielectric temperature performance may be attributed to the multiple elements doping strategy, which improves the dielectric constant while expanding the temperature region of dielectric temperature stability. This study presents a novel approach for achieving wide dielectric temperature stable range and high permittivity in BNT-based ceramics simultaneously.

Analysis of a Rainstorm Process in Nanjing Based on Multi-Source Observational Data and Lagrangian Method

Using multi-source observation data including automatic stations, radar, satellite, new detection equipment, and the Fifth Generation European Centre for Medium-Range Weather Forecasts Reanalysis (ERA-5) data, along with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) platform, an analysis was conducted on a rainstorm process that occurred in Nanjing on 15 June 2020, with the aim of providing reference for future urban flood control planning and heavy rainfall forecasting and early warning. The results showed that this rainstorm process was generated under the background of an eastward-moving northeast cold vortex and a southward retreat of the Western Pacific Subtropical High. Intense precipitation occurred near the region of large top brightness temperature (TBB) gradient values or the center of low TBB values on the northern side of the convective cloud cluster. During the heavy precipitation period, the differential propagation phase shift rate (KDP), differential reflectivity factor (ZDR), and zero-lag correlation coefficient (ρHV) detected by the S-band dual-polarization radar all increased significantly. The vertical structure of the wind field detected by the wind profile radar provided a good indication of changes in precipitation intensity, showing a strong correspondence between the timing of maximum precipitation and the intrusion of upper-level cold air. The abrupt increase in the integrated liquid water content observed by the microwave radiometer can serve as an important indicator of the onset of stronger precipitation. During the Meiyu season in Nanjing, convective precipitation was mainly composed of small to medium raindrops with diameters less than 3 mm, with falling velocities of raindrops mainly clustering between 2 and 6 m·s−1. The rainstorm process featured four water vapor transport channels: the mid-latitude westerly channel, the Indian Ocean channel, the South China Sea channel, and the Pacific Ocean channel. During heavy rainfall, the Pacific Ocean water vapor channel was the main channel at the middle and lower levels, while the South China Sea water vapor channel was the main channel at the upper level, both accounting for a trajectory proportion of 34.2%.

Anchored Weakly‐Solvated Electrolytes for High‐Voltage and Low‐Temperature Lithium‐ion Batteries

AbstractElectrolytes endowed with high oxidation/reduction interfacial stability, fast Li‐ion desolvation process and decent ionic conductivity over wide temperature region are known critical for low temperature and fast‐charging performance of energy‐dense batteries, yet these characteristics are rarely satisfied simultaneously. Here, we report anchored weakly‐solvated electrolytes (AWSEs), that are designed by extending the chain length of polyoxymethylene ether electrolyte solvent, can achieve the above merits at moderate salt concentrations. The −O−CH2−O− segment in solvent enables the weak four‐membered ring Li+ coordination structure and the increased number of segments can anchor the solvent by Li+ without largely sacrificing the ionic dissociation ability. Therefore, the single salt/single solvent AWSEs enable solvent co‐intercalation‐free behavior towards graphite (Gr) anode and high oxidation stability towards high‐nickel cathode (LiNi0.8Co0.1Mn0.1O2‐NCM811), as well as the formation of inorganic rich electrode/electrolyte interphase on both of them due to the anion‐rich solvation shells. The capacity retention of Gr||NCM811 Ah‐class pouch cell can reach 70.85 % for 1000 cycles at room‐temperature and 75.86 % for 400 cycles at −20 °C. This work points out a promising path toward the molecular design of electrolyte solvents for high‐energy/power battery systems that are adaptive for extreme conditions.

Anchored Weakly-Solvated Electrolytes for High-Voltage and Low-Temperature Lithium-ion Batteries.

Electrolytes endowed with high oxidation/reduction interfacial stability, fast Li-ion desolvation process and decent ionic conductivity over wide temperature region are known critical for low temperature and fast-charging performance of energy-dense batteries, yet these characteristics are rarely satisfied simultaneously. Here, we report anchored weakly-solvated electrolytes (AWSEs), that are designed by extending the chain length of polyoxymethylene ether electrolyte solvent, can achieve the above merits at moderate salt concentrations. The -O-CH2-O- segment in solvent enables the weak four-membered ring Li+ coordination structure and the increased number of segments can anchor the solvent by Li+ without largely sacrificing the ionic dissociation ability. Therefore, the single salt/single solvent AWSEs enable solvent co-intercalation-free behavior towards graphite (Gr) anode and high oxidation stability towards high-nickel cathode (LiNi0.8Co0.1Mn0.1O2-NCM811), as well as the formation of inorganic rich electrode/electrolyte interphase on both of them due to the anion-rich solvation shells. The capacity retention of Gr||NCM811 Ah-class pouch cell can reach 70.85 % for 1000 cycles at room-temperature and 75.86 % for 400 cycles at -20 °C. This work points out a promising path toward the molecular design of electrolyte solvents for high-energy/power battery systems that are adaptive for extreme conditions.

Low cycle fracture resistance of the superalloy at single- and two-frequency modes of loading

Fatigue and long static damages to the majority of high-loaded units develop under repeated stresses and strains of large amplitudes in elastic and elastoplastic regions at a low number of the main cycles and superimposition of dynamic stresses of significantly smaller value with higher frequencies which results in the so-called two-frequency modes of loading. It is shown that in the region of elevated and high temperatures, which determine the manifestation of temperature and time effects in the material, parameters of the rate and duration of deformation which enter the basic equation for determination of the fatigue life through the frequency and time of loading become the most significant parameters determining the fracture process. The results of theoretical and experimental study carried out on nickel superalloy specimens under a hard mode of loading and high temperatures have shown that estimation of the strength and fatigue life in this case for the single-frequency and two-frequency modes of loading can be performed on the basis of the analysis of strain parameters and diagrams of cyclic elastoplastic deformation using the deformation-kinetic criterion of summation of damages accumulated in the material. A decrease in the fatigue life under two-frequency mode of loading and the possibility of estimating it using the specified criterion and corresponding dependences with the introduction of the parameters of frequency/amplitude ratios of the strains (both full and that imposed on the main process) is experimentally proved. The calculated dependences include the parameters of temperature conditions, frequency and duration of loading which allows (when assessing damage from low-frequency and high-frequency components of cyclic strains) taking into account the effects of cyclicity and time of loading, as well as the existence of a variable coefficient of the asymmetry of high-frequency cycles of the two-frequency mode during high-temperature cyclic elastoplastic deformation.

Data-driven prediction of fracture toughness size effect in ductile-to-brittle transition using Two-Step-Scaling procedure

The fracture properties of ferritic steels in transition temperature region are usually statistically treated by models that presuppose the existence of various forms of quenched disorder (critical cleavage triggers). In this study, the fracture toughness from the Euro fracture toughness dataset (stress intensity factor used in the master curve KJc) for reactor steel 22NiMoCr37 is used with the aim of outlining a methodology for using the recently proposed two-step scaling (2SS) method. Three widely different temperatures (−154 °C, −91 °C, and 0 °C), which cover the entire range from lower shelf to upper shelf fracture, are selected to demonstrate the accuracy of extrapolation and interpolation of the fracture toughness CDF (cumulative distribution function) and the pertinent issues related to the procedure application. The obtained predictions at the two lower temperatures are in good agreement with the experimental results and well within the inherent experimental data scatter, while 2SS method is shown not to be applicable in upper-shelf transition region. Special attention is devoted to the effect of statistical sample size on prediction accuracy/reliability along with the minimum sample size requirement. Moreover, the reduction in random sample size affects the Weibull parameters, which in turn impacts the accuracy of predictions, introducing a degree of uncertainty and highlighting limitations in the method.

Effect of cooling rate in the mid-temperature region on fatigue crack propagation rate of bainitic steel

Controlling continuous cooling is an important means to control the most important mechanical properties of bainitic steel for frogs in railroad applications. In this paper, a bainitic steel for railway frogs is taken as the research object. By designing different cooling rates in the bainitic transformation medium temperature region, the effect of cooling rate on fatigue crack propagation rate was studied. The results show the sample of 4 °C/s cooling rate exhibits higher strength and impact toughness, while the crack propagation rate near the threshold is significantly lower and the threshold is relatively higher at 0.1 °C/s cooling rate. This is related to the fact that more massive blocky retained austenite and coarse microstructure in the sample at 0.1 °C/s cooling rate are more favorable to the occurrence of crack closure effect, especially in the near-threshold region. The fatigue crack propagation rate of the tested steel in the stable propagation region at 4 °C/s cooling rate is slightly higher than that at 0.1 °C/s. This is related to its complex interface distribution characteristics. However, with the increase of Δ K, the tested steel at 0.1 °C/s cooling rate tends to preferentially fail, which is related to its poor toughness.

Investigation of Residual Stress Effect on Cleavage Fracture Toughness in the Transition Temperature Region by Considering the Crack-Tip Constraint

Investigation of Residual Stress Effect on Cleavage Fracture Toughness in the Transition Temperature Region by Considering the Crack-Tip Constraint

Implementing the predictor-corrector approach to examine the thermo-solutal convection for buongiorno eyring-powell nanofluid model with squeezed microcantilivier surface

The Buongiorno nanofluid model serves as a foundational model for theoretical and experimental research in the field of nanofluids, and this model can be applied to various engineering problems, including heat exchangers, biomedical applications, solar collectors, nuclear reactors, and different cooling systems in the automotive and electronics industries. The use of nanofluids in the Eyring-Powell fluid over a squeezed sensing surfaces is a vital area of research for the design and improvement of microfluidic devices and sensors, which find widespread usage in industrial and medical applications. The main purpose of this work is to note the augmentation in thermal conductivity by using the Buongiorno nanofluid model along with the natural convective flow of non-Newtonian Eyring-Powell fluid that is moving on the squeezed sensory surface along with slip velocity. The viscosity of a fluid is assumed to be dependent on temperature. The Cattaneo-Christov heat and mass flux and chemical reaction are assumed to determine the combined effect of heat and mass transport. The governing model of equations is in the form of dimensional partial differential equations, and we have to convert these equations into ordinary differential equations; therefore, a set of similarity transformations is adopted for making the equations into dimensionless form. The numerical results were obtained by adopting the predictor and corrector multistep method, namely the ‘Adams-Bashforth’ technique, in Matlab software. The use of natural convective flow enhances the velocity region. The velocity slip parameter increases the velocity of the fluid, whereas the viscosity parameter drops the velocity profile. The thermophoresis and Brownian motion parameters are the sources of the increment in the temperature region. The thermal relaxation and solutal relaxation parameters are the sources of decline in the temperature region. The squeezing parameter is the source of reduction in the skin friction, whereas the result indicates that the fluid parameter, Grashof number, and viscosity coefficients increase the skin friction.

Competing Effects of Temperature and Polymer Concentration on Evolution of Re-entrant Interactions in the Nanoparticle-Block Copolymer System.

An interesting evolution of the re-entrant interaction has been observed in an anionic silica nanoparticle (NP)-block copolymer (P85) dispersion due to mutually competing effects of temperature and polymer concentration. It has been demonstrated that a rise in the temperature leads to an evolution of attraction in the system, which interestingly diminishes on increasing the polymer concentration. Consequently, the system exhibits a re-entrant transition from repulsive to attractive and back to repulsive at a given temperature but with respect to the increasing polymer concentration, within a selected region of concentration and temperature. The intriguing observations have been elucidated based on the temperature/concentration-dependent modifications in the interactions governing the system, as probed by contrast-variation small-angle neutron scattering. The initial transition from the repulsive to attractive system is attributed to the temperature-driven enhancement in the hydrophobicity of the amphiphilic triblock copolymer (P85) adsorbed on nanoparticles. The strength and range of this attraction are found to be more than van der Waals attraction while relatively less than electrostatic interaction. At higher polymer concentrations, the saturation of polymer adsorption on nanoparticles introduces additional steric repulsion along with electrostatic interaction between their conjugates, effectively reducing the strength of the attraction. However, with a significant increase in temperature (>75 °C), the attraction again dominates the system, which eventually leads to the particle aggregation at all the measured polymer concentrations (>0.1 wt %). Our study provides useful inputs to develop smart NP-polymer composites having capabilities to respond to external stimuli such as temperature/concentration variation.

The Marginal Effect and LSTM Prediction Model under the Chinese Solar Greenhouse Film

The solar greenhouse is a significant agricultural facility in China. It enables the cultivation of crops during periods that do not coincide with the natural growing season, thus alleviating the pressure on the supply of fruits and vegetables during the winter months. The primary rationale behind the necessity of greenhouse cultivation lies in the fact that the temperature conditions conducive to optimal crop growth can be precisely replicated within this controlled environment. However, it is important to acknowledge that a distinct low-temperature area persists under the film during the overwintering period, with the precise delineation of its boundaries and distribution patterns remaining uncertain. In order to investigate the characteristics of the temperature distribution within the marginal region under the solar greenhouse film, experimental studies, CFD simulations, and LSTM prediction models were employed. The results of these studies indicate that, during the overwintering period, a low-temperature region was observed with approximately equal temperatures near the film membrane. The maximum horizontal distance from the south-side bottom corner was 6130 mm, while the minimum height from the ground was 600 mm. The lowest temperature in the low-temperature region was 4 °C, and the maximum observed temperature difference within the same period in different months was 1 °C. Additionally, a region of elevated temperatures was observed under the film. The lowest temperature in this region was 36.7 °C, and the highest temperature point was within the optimal range for crop growth. The CFD numerical simulation results were consistent with the actual observations, and the LSTM prediction model demonstrated high reliability. The findings of this study offer a theoretical foundation for the distribution of high and low temperatures in solar greenhouses. Furthermore, the developed prediction model provides the necessary buffer time for control, thus enhancing the efficiency of greenhouse cultivation.

Fabrication of bulk-sized W-1.1%TiC alloy with helium bubble retention via powder metallurgical route incorporated with helium ambient mechanical alloying

In the field of materials irradiation, it has been noted that incorporating helium (He) element into metals may have the beneficial effect of improving both strength and ductility in the high temperature region where creep occurs. In order to fabricate such new functional materials and apply them to a wide range of fields, it is necessary to establish new fabrication methods for bulk-size materials. In this study, bulk-sized W-1.1%TiC alloys containing He bubbles were fabricated by a powder metallurgical route using mechanical alloying in a He atmosphere and subsequent thermo-mechanical processing. Transmission electron microscopy observations showed that this fabrication process successfully incorporated nano-sized He bubbles into W-1.1%TiC. Since this fabrication process is free of radioactivation and irradiation-induced defects, it will facilitate research into the fundamental understanding of the independent effects of He bubbles on the physical and mechanical properties of various materials concerned.

High In-Plane Thermoelectric Performance of Layered Bi4O4SeCl2.

The van der Waals semiconductor Bi4O4SeCl2 has recently attracted great interest due to its extremely small lattice thermal conductivity, which may find possible application in the field of energy conversion. Herein, we accurately predict the thermoelectric transport properties of Bi4O4SeCl2 using first-principles calculations and Boltzmann transport theory, where the carrier relaxation time is obtained by fully considering the electron-phonon coupling. It is found that a maximum p-type ZT value of 3.1 can be reached at 1100 K along the in-plane direction, which originates from increased Seebeck coefficient induced by multivalley band structure, as well as enhanced electrical conductivity caused by relatively stronger intralayer bonding. Besides, it is interesting to note that comparable p- and n-type ZT values can be realized in certain temperature regions, which is very desirable in the fabrication of thermoelectric modules.

Temperature Effect on the Interlayer Exchange Interaction in a Co/Pd/Co Heterostructure

Using Kerr microscopy, the magnetization reversal of the Co(0.4 nm)/Pd(6 nm)/Co(0.4 nm) heterostructure was studied in the temperature range 15–300 K. The temperature dependence of the domain nucleation field in a sample magnetized to saturation was obtained. The nucleation field in both ferromagnetic layers was shown to decrease monotonically with increasing temperature. A region of unstable temperatures of 160–174 K was found, below which the through domains of the new phase nucleated simultaneously in both layers, while in this region domains also nucleated simultaneously in different layers, but in different sites of the sample. The temperature dependence of the effective field HJ of the interlayer exchange interaction was obtained, which increased or decreased the pressure on the domain wall depending on whether this field was added to or subtracted from the external field.

Integrated assessment of decentralized wastewater treatment plants in semi-arid region in Bolivia

ABSTRACT This study comprehensively evaluates four decentralized wastewater treatment plants intended for agricultural reuse in a semi-arid low-moderate temperature region. It considers environmental, technical, economic, and social perspectives. Anaerobic baffled reactors with hybrid gravel filters (ABR + HGF + VGF) proved the most efficient, with moderate requirements in space, O&M, and energy, albeit the highest treatment cost. Up-flow sludge blanket reactor with activated sludge (UASB + AS) demonstrated high efficiency and compactness, with moderate treatment costs. However, it incurred high energy demands, complex O&M, and more sludge generation. UASB with horizontal gravel filter (UASB + HGF) was among the most land-intensive systems, with moderate costs and O&M requirements, and low energy consumption. However, it fell short of meeting certain environmental criteria. ABR with stabilization ponds (ABR + PONDS) emerged as the most economical, with low energy consumption, but was also among the most land-intensive and failed to achieve adequate effluent quality. Socially, all WWTPs were well accepted for agricultural reuse benefits. In terms of odor perception, UASB + AS and ABR + HGF + VGF exhibit the lowest impact. The Most Appropriate Treatment Technology Index (MATTI) ranked ABR + HGF + VGF and UASB + AS as adequate technologies, while UASB + HGF and ABR + PONDS were poorly adequate. The study recommends a four-dimensional assessment for selecting the most suitable technology, considering the specific context.

Lithology and elevated temperature impact phoD-harboring bacteria on soil available P enhancing in subtropical forests

Plants are generally limited by soil phosphorus (P) deficiency in forest ecosystems. Soil available P is influenced by lithology, temperature, and soil microbes. However, the interactive effects of these factors on soil P availability in subtropical forests remain unclear. To assess their impacts, we measured soil inorganic and available P fractions and the diversity, composition, and co-occurrence network of phoD-harboring bacteria in two contrasting forest soils (lithosols in karst forests and ferralsols in non-karst forests) in the subtropical regions of southwestern China across six temperature gradients. The present results showed that the complexities in composition and network and the diversity indices of phoD-harboring bacteria were higher in the karst forest soils than those in the non-karst forest soils, with marked differences in composition. In both types of forest soils, the complexities of composition and networks and the diversity indices were higher in the high-temperature regions (mean annual temperature (MAT) > 16 °C) compared to the low-temperature regions (MAT <16 °C). Soil total inorganic and available P contents were lower in the karst forest soils compared to the non-karst forest soils. Soil total available P contents were lower in the high temperature regions than those in the low temperature regions in both forest soils, whereas soil total inorganic P contents were contrary. Variance partitioning analysis showed that soil inorganic and available P fractions were predominantly explained by lithology and its interaction with soil microbes and climate. The present findings demonstrate that soil P availability in subtropical forests of southwestern China is influenced by lithology and temperature, which regulate the diversity, composition, and network connectivity of phoD-harboring bacteria. Furthermore, this study highlights the significance of controlling the composition of phoD-harboring bacteria for mitigating plant P deficiency in karst ecosystems.

Tunable thermal expansion via the magnetic phase competition in kagome magnets

Negative thermal expansion materials can solve the challenge of mismatched coefficients of thermal expansion of components in precision instruments, thereby improving the thermal shock resistance of devices. The adjustment of negative thermal expansion performance can improve the universality of its application. In this work, tunable thermal expansion has been achieved in Hf1−xTaxFe2 kagome magnets via magnetic phase competition. The transition from ferromagnetism to antiferromagnetism results in a sharp volume shrinkage of Hf0.83Ta0.17Fe2 within a narrow temperature range of 190–230 K, which limits its practical application. As the Ta content decreases, the ferromagnetic ground state becomes more robust and eventually suppresses the antiferromagnetism completely, achieving a negative thermal expansion in Hf0.88Ta0.12Fe2 caused by the ferromagnetic to paramagnetic transition over a wide temperature region and containing room temperature (αV = −37.63 × 10−6 K−1, 250–350 K). This work realizes the regulation of negative thermal expansion through magnetic phase competition, which provides guidance for the regulation of thermal expansion of magnetic materials in the future.

Effects of Fe substitution for Mn on structural, magnetic and magnetocaloric properties of TbMn2-xFexSi2

The structural and magnetic properties of TbMn2-xFexSi2 compounds (x = 0.0–0.4) have been investigated in details by high-resolution synchrotron x-ray and neutron powder diffraction, specific heat, and dc magnetization measurements. The replacement of Fe for Mn in TbMn2-xFexSi2 does not change the crystal structure but leads to a significant contraction of the unit cell (dV/dx ∼ - 6 Å3) and modification of three magnetic phase transition temperatures – the Curie temperatures Tc1, Tc2 and the Néel temperature TN. For example, the Tc1, Tc2 and TN values of TbMn2Si2 decrease from Tc1 = 50 K, Tc2 = 64 K and TN = 500 K to Tc1 = 27 K, Tc2 = 37 K and TN = 440 K for TbMn1.6Fe0.4Si2. Detailed neutron diffraction investigations have allowed us to determine the magnetic structures and construct the magnetic phase diagram as well as confirm the presence of magnetoelastic coupling effects. The significantly different responses of Tc1 and Tc2 to applied magnetic fields (e.g. dTc1/dB = 0.52 K/T and dTc2/dB = 4.7 K/T for TbMn1.6Fe0.4Si2), leads to expansion of the temperature region (ΔT = Tc2- Tc1) for the canted ferromagnetic state Fmc-ii between Tc1 and Tc2. In the case of TbMn1.6Fe0.4Si2, ΔT increases from ΔT = 9 K for applied magnetic field B = 0.2 T to ΔT = 36 K for B = 6 T, resulting in plateau-like behaviour of magnetic entropy change and enhances the relative cooling power (RCP) in this system. Under a change of magnetic field of 0 T – 5 T, the maximum value of the magnetic entropy changes -ΔSmax and adiabatic temperature change, ΔTad are derived to be -ΔSmax = 13.1 J/kg K and ΔTad = 8.4 K with the RCP = 411 J/kg for x=0.4 sample. The plateau-like magnetocaloric effect and relatively large RCP make these materials potentially suitable for application in cryogenic magnetic refrigeration.

A high sensitivity temperature coefficient of the Au/n-Si with (CdTe-PVA) structure based on capacitance/conductance-voltage (C/G-V) measurements in a wide range of temperature

This study focused on revealing the temperature-sensing performance and rudimental electrical-properties of the Au/(CdTe-PVA)/n-Si depending on the temperature via impedance-measurements. The temperature-sensitivity (S) for constant-capacitance drive mode shows two-distinct linear-regions corresponding to low/moderate temperatures. The highest S value was achieved as 15.5 mV/K at 0.60 nF value. Nicollian-Brews and Hill-Coleman methods were applied to determine series-resistance (RS) and density of surface-states (NSS) values. The low RS values and the proper magnitude of NSS demonstrate the high quality and performance of the Au/(CdTe-PVA)/n-Si. Additionally, the electrical parameters obtained from C-2-V plots show almost temperature-independent behavior at moderate temperature regions. The low activation-energy values (Ea) determined via Arrhenius-plot indicate hopping of the trapped electron from trap to trap or conduction band dominates the ac conduction. In conclusion, the variations of electrical-parameters and the high S value consolidate the usability of Au/(CdTe-PVA)/n-Si as a thermal sensor in the low-temperature regions.