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Electrocaloric effect (ECE) refrigeration stands out as a promising alternative to conventional compression refrigeration owing to its potential for miniaturization, high energy conversion efficiency, cost-effectiveness, and environmental friendliness. However, the practical applications of ECE refrigeration in lead-free ceramics face limitations due to the challenge of achieving a substantial adiabatic temperature change (Δ T) and a wide operating temperature span (T span). In this study, we tackle this challenge by introducing rare-earth Sm3+ ions into Ba(Ti 0 · 90 Sn 0.10)O 3 (BTSn) ceramics to enhance their ECE stability. We comprehensively investigate the structural, dielectric, and ECE properties of (Ba 1−3 x /2 Sm x) (Ti 0 · 9 Sn 0.1)O 3 (BSmTSn, x = 0−0.03) ceramics. Our findings reveal that the incorporation of Sm3+ ions leads to a reduction in the temperature at which the permittivity reaches its maximum, accompanied by an increased dispersion compared to undoped BTSn ceramics. Particularly noteworthy is the achievement of a Δ T of 0.9 K with a T span of 55.5 °C in the x = 0.005 composition. Furthermore, increasing x to 0.01 enables the realization of a wide T span of 70 °C, starting from 30 °C. These significant enhancements in the T span across all BSmTSn ceramics, facilitated by the introduction of Sm3+ ions, present a promising strategy for optimizing the ECE performance of BaTiO 3 -based ceramics. [ABSTRACT FROM AUTHOR]

PurposeFew studies examined the relationship between temperature fluctuation metrics and acute myocardial infarction (AMI) hospitalizations within a single cohort. We aimed to expand knowledge on two basic measures: temperature range and difference.MethodsWe conducted a time-series analysis on the correlations between temperature range (TR), daily mean temperature differences (DTDmean), and daily mean-maximum/minimum temperature differences (TDmax/min) and AMI hospitalizations, using data between 2013 and 2016 in Beijing, China. The effects of TRn and DTDmeann over n-day intervals were compared, respectively. Subgroup analysis by age and sex was performed.ResultsA total of 81,029 AMI hospitalizations were included. TR1, TDmax, and TDmin were associated with AMI in J-shaped patterns. DTDmean1 was related to AMI in a U-shaped pattern. These correlations weakened for TR and DTDmean with longer exposure intervals. Extremely low (1st percentile) and high (5°C) DTDmean1 generated cumulative relative risk (CRR) of 2.73 (95% CI: 1.56–4.79) and 2.15 (95% CI: 1.54–3.01). Extremely high TR1, TDmax, and TDmin (99th percentile) correlated with CRR of 2.00 (95% CI: 1.73–2.85), 1.71 (95% CI: 1.40–2.09), and 2.73 (95% CI: 2.04–3.66), respectively. Those aged 20–64 had higher risks with large TR1, TDmax, and TDmin, while older individuals were more affected by negative DTDmean1. DTDmean1 was associated with a higher AMI risk in females.ConclusionTemperature fluctuations were linked to increased AMI hospitalizations, with low-temperature extremes having a more pronounced effect. Females and the older adult were more susceptible to daily mean temperature variations, while younger individuals were more affected by larger temperature ranges.

Developing a good understanding of the interactions between forest plantation growth and climate is essential for predicting the impact of climate change on terrestrial ecosystems and for assessing the adaptation and vulnerability of tree species. One such interaction, the response in growth rate of a forest stand to changes in temperature, may be described mathematically. Some models that run on monthly time steps assume a yearly optimum, minimum, and maximum temperature for simplicity, which may not represent well to actual forest growth. Here, we developed a finer-resolution methodology that encompasses monthly growth rates and temperature limits to calibrate the parameters for an envelope curve in Eucalyptus plantations in South America. Several polynomial curves were tested to determine temperature patterns, and their yearly tree growth patterns demonstrated that responses to temperature differed by as much as 10 °C among seasons. The best curve was a second-degree polynomial curve, whose extreme values indicated the optimum temperature and whose real roots limited the minimum and maximum temperatures for growth. This polynomial was fitted every month to describe yearly changes in optimum, maximum, and minimum temperatures. When fitted to annual data, it determined 7 °C, 19 °C, and 31 °C as the minimum, optimum, and maximum temperatures for tree growth, respectively. The monthly model predictions indicated that the minimum, optimum, and maximum temperatures lay between 8 °C and 16 °C, 18 °C and 22 °C, and 27 °C and 30 °C, respectively. These monthly temperature ranges can improve the estimation of productivity in process-based models. Our results contribute to the understanding of tree growth dynamics and its relationship to changes in temperature. Accurate ranges of temperature can be used to improve productivity predictions in new expanding planting regions with no previous information or to suggest a regionalization for potential species. [ABSTRACT FROM AUTHOR]

The development of blue-phase liquid crystal (BPLC) materials with a wide temperature range is of great significance for practical applications in the optoelectronic field. In the study, bent-core derivatives with a 3-hexyl-2,5-disubstituted thiophene central ring in the λ-shaped molecular structure were designed and synthesized. Their mesomorphic behavior and effect on the blue-phase (BP) temperature range were investigated. Interestingly, a BP was achieved both during the heating and cooling processes by doping with a proper concentration of chiral compound into the thiophene bent-shaped molecule with high rigidity, while derivatives with fluorine atom substitution only exhibited cholesteric phase no matter how many chiral compounds were added. This result proved that BP is highly sensitive to the molecular structures of bent-shaped molecules. Moreover, the BP temperature range was broadened when adding these molecules into a BPLC host, which thus improved the BP temperature range from the initial value, no more than 4 °C, to as much as 24 °C. The experimental phenomena were reasonably explained through molecular simulation calculations. The study may provide some experimental basis and theoretical guidance for the design of novel bent-shaped molecules and BPLC material with a wide temperature range. [ABSTRACT FROM AUTHOR]

Holopelagic Sargassum species have bloomed recurrently in the northern tropical Atlantic since 2011, causing socioeconomic and environmental problems. Little is known about their basic biology and responses to the abiotic environment. The aim of this study was to determine how temperature affects the growth rates of the genotypes S. fluitans III, S. natans I, and S. natans VIII that predominate in these blooms. The growth rates were evaluated in specially designed ex situ systems between 22 and 31 °C, which corresponds with the natural temperature range of these seaweeds in the northern tropical Atlantic. All the genotypes had decreased growth rates at 31 °C, and they varied in their response to temperature, with S. fluitans III presenting a maximal rate of 0.096 doublings· day−1 (doubling its weight in 10.5 d) at 28 °C and S. natans VIII a minimal rate of 0.045 doublings· day−1 (doubling its weight in 22.2 d) at 31 °C. In addition, the response to the temperature varied depending on the time of the year. Understanding the role of temperature in the growth of holopelagic Sargassum genotypes, amongst other factors influencing their physiology (such as nutrients, salinity tolerance, or light, including their interactions), could help to understand the dynamics of the recent blooms in the tropical North Atlantic.

Holopelagic Sargassum species have bloomed recurrently in the northern tropical Atlantic since 2011, causing socioeconomic and environmental problems. Little is known about their basic biology and responses to the abiotic environment. The aim of this study was to determine how temperature affects the growth rates of the genotypes S. fluitans III, S. natans I, and S. natans VIII that predominate in these blooms. The growth rates were evaluated in specially designed ex situ systems between 22 and 31 °C, which corresponds with the natural temperature range of these seaweeds in the northern tropical Atlantic. All the genotypes had decreased growth rates at 31 °C, and they varied in their response to temperature, with S. fluitans III presenting a maximal rate of 0.096 doublings· day−1 (doubling its weight in 10.5 d) at 28 °C and S. natans VIII a minimal rate of 0.045 doublings· day−1 (doubling its weight in 22.2 d) at 31 °C. In addition, the response to the temperature varied depending on the time of the year. Understanding the role of temperature in the growth of holopelagic Sargassum genotypes, amongst other factors influencing their physiology (such as nutrients, salinity tolerance, or light, including their interactions), could help to understand the dynamics of the recent blooms in the tropical North Atlantic. [ABSTRACT FROM AUTHOR]

Benzene with Butyl/Pentyl Parabens is evaluated using the volumetric and acoustic study as a function of temperature. The properties such as partial and apparent molar volumeand partial and apparent molar compressibility of the mixtures were studied. The thermoacoustic properties of the mixture, such as acoustic impedanceand free lengthwere analyzed. These measurements were utilized to interpret the intermolecular interactions among the constituents. [ABSTRACT FROM AUTHOR]

Introduction. Providing people with high quality drinking water has always come first. However, its transportation through pipeline systems was often associated with some problems, such as the temperature of the water and the environment, as well as the possibility of water hammer on certain pipe sections. This was especially true for systems that use polyethylene pipes. Temperature is a key factor affecting the flexibility properties of polyethylene pipes, and it affects not only the design, but also the investment in the development of water supply networks. The purpose of these studies was to study the effect of water and ambient temperature on the density, properties of the pipe material and the speed of propagation of a hydraulic shock wave in polyethylene pipes.Materials and Methods. In the experiments performed, the method of field research was used, when tests are carried out on specialized equipment on samples specially made for the pursued purposes. Here, samples of high-density polyethylene pipes were used, which were subjected to tensile tests on a tensile testing machine, and each experiment was carried out three times.In the course of the experiments, the samples were exposed to certain temperature regimes (both external and internal), while the influence of the hydrodynamic pressure of the liquid in the pipe was also investigated, as a result of the change in time of the liquid velocity in its sections. To do this, the samples were supplied with liquid under a certain pressure in order to find out the influence on the pipes of an effect known as water hammer.Results. In the course of the research, it was found that the value of the elastic modulus of high-density polyethylene PE100 decreases with increasing water temperature, and the decrease at a temperature of 60° C reaches 60.21% compared to its value at a water temperature of +4° C. Based on the results of experiments to determine the effect of the elastic modulus of polyethylene with increasing temperature, an exponential equation was derived to calculate the value of the polyethylene coefficient as a function of time E = 1.312e-0,01t with the correlation coefficient R2 = 0.988 ; and based on the results of the studies carried out to calculate the value of the propagation velocity of a hydraulic shock wave, an exponential equation was derived as a function of time C = 275.9e-0,01t with the coefficient correlation R2 = 0.987 .Discussion and Conclusions. In the course of the research, it was found that such a phenomenon as water hammer has a harmful effect on the pipe walls, which, if possible, should be avoided even at the design stage of the water supply network. During the experiments, it was found that with an increase in temperature, the values of the elastic modulus of polyethylene decreased with a simultaneous decrease in the values of the propagation velocity of the hydraulic shock wave.

Temperature sensitivity (Q10) of soil organic matter (SOM) decomposition is an essential parameter that reflects the feedback relationship between climate warming and atmospheric CO2 concentration and plays a key role in accurately estimating changes in soil carbon pools and their feedback to climate change. Setting the incubation temperature range (ITR) scenario is essential to accurately estimate the temperature sensitivity of SOM decomposition; however, this has been widely ignored. To address this issue, we conducted a systematic incubation experiment using 54 soils covering the most typical ecosystems in China and nine ITR scenarios. The results showed that ITR scenarios had a significant effect on Q10 in different ecosystems and soil types. Combining the results of fitting mean annual temperature (MAT) to the Q10 of different ITR and the interpretation rate of factors (including climate, soil, and microbial community composition) to the Q10 of different ITR, the results indicate that the growing season average temperature range (GSA) scenario had better performance than the other ITR scenarios and should be the optimum ITR scenario. Furthermore, the variation of main influence factors of Q10 across different ecosystems should be accounted for to accurately predict the feedback between soil C cycle and climate change. Overall, our findings highlight the importance of the ITR for the estimates of Q10 using widespread experimental data, providing a reference for subsequent experiments accurately measure Q10, as well as compare and compile global data to better predict the feedback between the global carbon cycle and climate change.

Developing a good understanding of the interactions between forest plantation growth and climate is essential for predicting the impact of climate change on terrestrial ecosystems and for assessing the adaptation and vulnerability of tree species. One such interaction, the response in growth rate of a forest stand to changes in temperature, may be described mathematically. Some models that run on monthly time steps assume a yearly optimum, minimum, and maximum temperature for simplicity, which may not represent well to actual forest growth. Here, we developed a finer-resolution methodology that encompasses monthly growth rates and temperature limits to calibrate the parameters for an envelope curve in Eucalyptus plantations in South America. Several polynomial curves were tested to determine temperature patterns, and their yearly tree growth patterns demonstrated that responses to temperature differed by as much as 10 °C among seasons. The best curve was a second-degree polynomial curve, whose extreme values indicated the optimum temperature and whose real roots limited the minimum and maximum temperatures for growth. This polynomial was fitted every month to describe yearly changes in optimum, maximum, and minimum temperatures. When fitted to annual data, it determined 7 °C, 19 °C, and 31 °C as the minimum, optimum, and maximum temperatures for tree growth, respectively. The monthly model predictions indicated that the minimum, optimum, and maximum temperatures lay between 8 °C and 16 °C, 18 °C and 22 °C, and 27 °C and 30 °C, respectively. These monthly temperature ranges can improve the estimation of productivity in process-based models. Our results contribute to the understanding of tree growth dynamics and its relationship to changes in temperature. Accurate ranges of temperature can be used to improve productivity predictions in new expanding planting regions with no previous information or to suggest a regionalization for potential species.

The development of blue-phase liquid crystal (BPLC) materials with a wide temperature range is of great significance for practical applications in the optoelectronic field. In the study, bent-core derivatives with a 3-hexyl-2,5-disubstituted thiophene central ring in the λ-shaped molecular structure were designed and synthesized. Their mesomorphic behavior and effect on the blue-phase (BP) temperature range were investigated. Interestingly, a BP was achieved both during the heating and cooling processes by doping with a proper concentration of chiral compound into the thiophene bent-shaped molecule with high rigidity, while derivatives with fluorine atom substitution only exhibited cholesteric phase no matter how many chiral compounds were added. This result proved that BP is highly sensitive to the molecular structures of bent-shaped molecules. Moreover, the BP temperature range was broadened when adding these molecules into a BPLC host, which thus improved the BP temperature range from the initial value, no more than 4 °C, to as much as 24 °C. The experimental phenomena were reasonably explained through molecular simulation calculations. The study may provide some experimental basis and theoretical guidance for the design of novel bent-shaped molecules and BPLC material with a wide temperature range.

• Diagram of solubility in the studied quaternary water-salt system at the different temperatures was calculated on the base of classical Pitzer's equations. • Temperature of double salt formation in ternary and quaternary systems was determined. • Classification of non-variant points was provided. Diagram of solubility in quaternary water-salt system N a + , N i 2 + / / C l - , S O 4 2 - - H 2 O in the temperature range −5 ÷ 90 °С was calculated on the base of classical Pitzer's equations. Linear temperature approximation of solubility products of solid phases was used. [ABSTRACT FROM AUTHOR]

The paper considers the issues of technology for soldering a terminal (contactor) to auto-glass heating systems for cars, i.e. technology of soldering metal to non-metal bodies. A technique for conducting an experiment measuring temperature on a setup specially designed for this system is described. The results of experimental studies using various solder compositions are presented. The optimal variants of terminal soldering technologies for auto glass heating systems are determined and presented. Purpose: Experimental study of the soldering process of the terminal to the auto-glass heating system in a specially designed soldering installation. The soldering plant is designed and built using modern computer automation tools. Methods: In the experiments, automatic control systems were used to control the load supply to the soldering irons and the pressure on them. Registration (removal of information) was carried out on the SAMKOON touch panel. Results: Experimental data were obtained that provide temperatures for the optimal soldering mode of the terminal to heating systems. Conclusion: It has been experimentally proven that to obtain the required soldering of the terminal to the auto glass base, it is necessary to create a multilayer base and use hard solder that wets the soldered layer. The temperature holding interval of the soldering iron is in the range of 161 ÷ 242 ℃. The composition and weight of the solders used in soldering were also investigated.

Problems. In the process of obtaining a strip in a casting and rolling device, the question arises of combining the process of hot rolling of the solidified material and the process of crystallization of the liquid melt. This makes it possible to implement an efficient technology for producing thin-sheet products. Purpose of the study. Determination of rational parameters for performing mathematical modeling of material behavior during roll casting requires clearly defined recommendations. The material for the rolling process is steel. The starting material was used in solid, solid-liquid and liquid states. Implementation technique. The analysis of the properties of steel was carried out on the basis of the results of experiments obtained at the Physico-Technological Institute of Metals and Alloys of the National Academy of Sciences of Ukraine. To analyze the rheological properties of steel, the dependences of the yield stress for alloyed and carbon steels were used in a certain temperature range. The selected temperature range includes solidus and solid-liquid state of steel, located above 0.8 melting point. Research results. Based on the research results, the analysis of the rheological properties of steel in solid, solid-liquid and liquid states during continuous casting-rolling on rolls was carried out. The use of the obtained dependencies makes it possible to perform mathematical modeling of the deformation and hydrodynamics of the material during continuous casting-rolling of steel strips using roll casting-rolling devices. Conclusions. The constructed dependences, together with studies of the viscosity of steel in the liquid state and the resistance of steel to deformation in the solid state, most fully describe the rheological properties of steels during casting-deformation processes. The obtained dependences will make it possible to implement an ultra-efficient technology for producing thin-sheet rolled products.

The paper presents a low supply voltage CMOS voltage reference with low line sensitivity and high PSRR. Generally, the reference voltage is obtained using both complementary-to-absolute-temperature (CTAT) current and proportional-to-absolute-temperature (PTAT) current. This technique increases the complexity and area of the reference circuit. To overcome these drawbacks, the temperature compensated reference voltage has been proposed using only CTAT currents. Mostly, the CTAT current generators are simple, power-efficient, and area-efficient as compared to the PTAT current generators. The negative feedback loop has been formed in the proposed design to obtain a supply independent CTAT current and to avoid the use of startup drivers. The proposed circuit has been designed using Cadence virtuoso analog design environment in BSIM3V3 180 nm CMOS technology. The simulation results of the proposed circuit show a reference voltage of 312 mV with a temperature coefficient (TC) of 38.85 ppm/∘C over a wide temperature range of − 4 0 ∘ C to 125∘C with a supply voltage of 0.8 V. The line sensitivity is 0.027% ∕ V with a supply voltage ranging from 0.8 V to 3 V. The power supply rejection ratio (PSRR) without using any capacitive filter is observed as − 8 0. 8 4 and − 7 1. 6 6 dB at 100 Hz and 100 kHz frequency, respectively. The circuit is simple and occupies a chip area of 0.0027 mm2. [ABSTRACT FROM AUTHOR]

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Fish are considered auspicious and powerful in Vastu shastra, and they reflect good fortune, prosperity, and abundance in feng shui. Additionally, fish can provide a high degree of positive vibes, create a pleasant environment, relieve stress, and assist in a good night's sleep. Proper management of a fish tank at home will help to reduce hypertension and a rapid heartbeat. The quality and liquid level, the number of calories fed to the fish, the feeding cycles, and temperature fluctuations are all assessed. The project's objective is to computerize the system and reduce human intervention, by using a smartphone where the control for initiating the system can be done remotely by the user. Simultaneously, instant data of the feed, volume of water, the ambience of the water tank are noticed by the user and hence one can monitor the system in his/her absence. Tinkercad is used to build the simulation results. [ABSTRACT FROM AUTHOR]

The influence of the soldering temperature on the performance of flip-chip light-emitting diodes (FC-LED) filaments soldered with SAC0307 has been investigated. Scanning electron microscopy (SEM) images, void rates, shearing force, junction temperature, steady-state voltage, blue light luminous flux, and luminous efficiency were measured to characterize the filament performance. The microstructure of the fracture surface after shear failure of the FC-LED filament joints soldered at 250°C and 270°C showed the lowest percentage of voids and was smoother than for the other groups. The shearing force of the FC-LED filament solder joints formed at 250°C and 270°C was higher than that for the other three groups, but the shearing force of all five groups of solder joints exceeded 200 gf. The steady-state voltage and junction temperature of the 250°C and 270°C FC-LED filaments were lower than those of the other three groups, and the blue light luminous flux of the 250°C and 270°C FC-LED filaments was higher than for the other three groups. In conclusion, the FC-LED filaments exhibited good photoelectric performance and thermal reliability when using soldering temperatures between 250°C and 270°C. [ABSTRACT FROM AUTHOR]

Cold agglutinin are erythrocyte antibodies which possess the property of agglutinating red blood cells at temperatures of below 37°C, this phenomenon is reversible after heating. This is usually immunoglobulin M (IgM) class. Their pathogenicity is much more related to their temperature range of activity than their title. As we report in this observation, cold hemagglutination makes it difficult to interpret certain immunological tests such as ABO Rh blood grouping or searching for irregular antibodies (SAI). The discovery of cold agglutinins can be fortuitous revealing itself by disturbances and aberrations in the results of blood count or as part of a suggestive clinical or laboratory table cold hemagglutinin disease. The search for a lymphoid hematological at their diagnosis should be systematic.

Cold agglutinin are erythrocyte antibodies which possess the property of agglutinating red blood cells at temperatures of below 37°C, this phenomenon is reversible after heating. This is usually immunoglobulin M (IgM) class. Their pathogenicity is much more related to their temperature range of activity than their title. As we report in this observation, cold hemagglutination makes it difficult to interpret certain immunological tests such as ABO Rh blood grouping or searching for irregular antibodies (SAI). The discovery of cold agglutinins can be fortuitous revealing itself by disturbances and aberrations in the results of blood count or as part of a suggestive clinical or laboratory table cold hemagglutinin disease. The search for a lymphoid hematological at their diagnosis should be systematic. [ABSTRACT FROM AUTHOR]

Amazonian protected areas (PAs) play an important role in maintaining the regional and global ecosystem services, biodiversity and climate change mitigation. The effects of Amazonian PAs on climate change mitigation mainly focus on the carbon sequestration benefits. The biophysical effects of PAs on regulating the local energy budgets, and hence changing local climate, however, are often ignored. Using multiple satellite observation datasets, we evaluated the effects of Amazonian PAs on land surface temperature (LST) and the biophysical mechanisms of PAs on surface albedo and evapotranspiration (ET). We showed that Amazonian PAs have a cooling effect on local LST in relative to nearby croplands and non-protected areas (non-PAs) with the same land cover as PAs. The asymmetrical cooling effects of Amazonian PAs between daytime and nighttime, and between the dry and wet seasons sustain lower diurnal and seasonal temperature ranges, respectively, than non-PAs and croplands. The protected forests have stronger cooling effects, and more effectively moderate the diurnal and seasonal temperature ranges than the protected savannas due to the higher effects on surface albedo and ET. The non-PAs show weaker cooling effect than PAs, indicating reduced thermal buffering effect in non-PAs. Our results highlighted the great potential of natural vegetation in PAs versus non-PAs and croplands in buffering local thermal environment and the necessity of natural vegetation conservation in Amazon region.

The seasonal freeze-thaw environment is a primary factor contributing to the deterioration of manually excavated disturbed rock masses on reservoir bank slopes in highland alpine areas. To investigate the mechanical properties and damage deterioration mechanism of excavation-unloading rock under seasonal freeze-thaw environment in cold region, the freeze-thaw cycle tests with different temperature difference levels (−10–10 °C, −15–25 °C, −20–40 °C) and different cycle times (0,10,20,30) were simulated for the triaxial unloading damaged marble. Then, the mechanical parameters of unloaded marble after freezing and thawing were obtained by uniaxial compression and triaxial compression tests, and the influence laws of temperature ranges, number of freezing and thawing cycles and confining pressure on the mechanical properties of unloaded marble were analyzed. Finally, the damage model of unloaded marble considering freeze-thaw action was established. The results show that the strength of unloaded marble is significantly weakened under the combined effect of F-T (freezing and thawing) and loading, and that the deterioration effect of the number of F-T cycles is stronger than that of the temperature ranges. The increase in the confining pressure increased the compressive strength and elastic modulus of the unloaded marble, and suppressed the damage of the unloaded marble after the freeze-thaw treatment. The porosity of the unloaded marble developed gradually and increased exponentially with the increase of the number of freeze-thaw cycles, the compressive strength and elastic modulus had a negative exponential relationship with the number of freeze-thaw cycles, and the shear strength parameter had a quadratic polynomial relationship with the number of freeze-thaw cycles. In addition, the softening mechanism of unloaded marble by natural water plays a key role in the process of freeze-thaw cycle, and the damage model considering freeze-thaw is established, and the theoretical curves are well matched with the experimental results. The outcomes of this study hold significant theoretical and engineering importance for evaluating the stability of excavated unloaded rock in highland alpine regions. • Unloaded marble mechanical properties tested under freeze-thaw and confining pressures. • The coupling effects of different freeze-thaw temperature ranges, cycles and confining pressures were analyzed. • A model of unloaded marble considering freezing-thawing and load was established. [ABSTRACT FROM AUTHOR]