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Focusing on the issue of thermal deformation in dry hobbing machine tools, the mechanisms of temperature change and the characteristics of temperature rise are thoroughly investigated. By analyzing heat generation through the energy conversion of various heterogeneous forms, including electrical, mechanical, and hydraulic energy, a comprehensive heat transfer model is developed to elucidate the complex thermal processes within the dry hobbing machine tool. The temperature at critical points of the machine tool during the dry hobbing of automotive gears is measured using a combination of infrared thermal imaging and online sensor technology. Experimental data are processed using Python to generate the machine tool's temperature rise curve. Based on this analysis, the temperature rise characteristics of the dry hobbing machine tool are further explored. The findings provide valuable insights for controlling thermal deformation and designing thermal balance systems for dry hobbing machine tools. [ABSTRACT FROM AUTHOR]

The process of coal and gas outburst (hereinafter referred to as "outburst") is inevitably accompanied by temperature variation. To further reveal the temperature evolution law and proposal of risk indicator of deep outburst, taking the outburst coal seam of Pingmei No.11 Coal Mine as the research object, the outburst tests with simulated buried depths of 600 m, 800 m, 1000 m, 1200 m, 1400 m, and 1600 m are carried out. The relationship between outburst parameters (critical gas pressure, test-effective stress), acoustic emission signal, and temperature variation is analyzed. The approximate range of the critical buried depth of Pingmei No.11 Coal Mine is given. According to the characteristics that the temperature variation decreases earlier than the acoustic emission signal, a new outburst risk indicator is established. The results show that the coal-seam temperature variation in the outburst process is determined by gas pressure and gas content. When the buried depth is higher than the critical depth, the influence of gas content on outburst is intensified, and the sensitivity of outburst to gas content is greater than that of gas pressure. The test-effective stress is negatively correlated with temperature, and the gas-expansion work is positively correlated with temperature. The development of outburst leads to the variation in internal temperature of coal seam. The temperature variation eventually reacts to the development of outburst. The risk indicators P2, N1, N2, and S are defined based on acoustic emission signal and temperature variation. According to the change of risk indicators, the outburst risk is divided into four grades: "no, weak, moderate, and strong", which is of great significance for the prediction and early warning of outbursts. Highlights: The development of outburst incubation leads to the variation of internal temperature of coal seam, and the temperature variation eventually reacts to the development of outburst incubation. The variation of internal temperature of coal seam in the outburst process is determined by gas pressure and gas content. When the critical buried depth is exceeded, the sensitivity of outburst to gas content is greater than that of gas pressure. The difference in falling time between of temperature variation and gas pressure in the process of outburst incubation is obtained. A new risk indicator of outburst based on AE signal and temperature variation is proposed. [ABSTRACT FROM AUTHOR]

Infrared thermography techniques have proven to be very effective for assessing the fatigue limits of metallic materials with obvious temperature variations. But for some materials, it has been shown that the temperature variation is very limited, and the accuracy of infrared thermographic techniques is not verified. In this study, the fatigue properties of a high-strength steel (SAE52100) were evaluated with traditional fatigue-loading techniques and infrared thermographic methods. The traditional fatigue experiments were loaded at a frequency of 80 Hz with a stress ratio of R = −1, and the fatigue limit at the fatigue lifetime of N = 107 cycles was about 800 MPa. Besides, three additional specimens were loaded with step-by-step increasing stress-loading amplitude, where the maximum temperature increments and temperature distribution were recorded via infrared thermographic techniques. The infrared detections revealed that the maximum value of the temperature increase was only about 1 °C. The fatigue limit was first evaluated based on the maximum temperature variation, then the prediction was refined based on fatigue intrinsic dissipation. The fatigue limits predicted with maximum temperature variation were shown to be 841 MPa, 772 MPa, and 787 MPa, respectively, while the fatigue limits predicted based on fatigue intrinsic dissipation were 793 MPa, 791 MPa, and 789 MPa. Finally, an FEM simulation of temperature variation during fatigue loading was implemented to verify the experimental results. This study provides a solid foundation for the applications of infrared thermography techniques for materials with lower energy dissipations. [ABSTRACT FROM AUTHOR]

AbstractThis article presents the Airy stress function method for predicting the structural response of a fixed beam subjected to a linear temperature distribution, using the superposition principle. In this approach, the fixed-end beam is decomposed into three simply supported beams with unknown reactions and a linear temperature variation. For each loading condition, the suitable Airy’s stress functions were formulated to satisfy the stress equilibrium and strain compatibility equations. The results obtained using this method are subsequently contrasted with those derived from finite element modeling. To validate the analytical and experimental results, two finite element modeling approaches, namely two-dimensional and three-dimensional modeling, are implemented using the ANSYS finite element software. This numerical modeling approach utilizes a sequentially coupled steady-state thermal and static structural analysis. In addition to employing Airy’s stress function method and finite element analysis, experiments were conducted on SS304 rectangular specimens under proper insulation to investigate their thermal bowing response. Samples were tested in a simple thermal bending experimental setup under fixed support conditions, and subjected to conduction-type heating to achieve linear temperature changes along their depth. The analytical method predicts that the beam will not deflect under linear temperature variation in a fixed-beam situation. The numerical analysis results confirm this, showing a minimal deflection, that aligns well with the Airy’s stress function method. However, the deflection measured in the experimental program is significantly larger than the predictions from the analytical method. This method eliminates the complexity involved in applying boundary conditions along with thermal loading on a fixed beam. [ABSTRACT FROM AUTHOR]

This study assessed the impact of various temperature indices, including mean temperature (MT), diurnal temperature range (DTR), and temperature changes between neighboring days (TCN) on hospitalization rates for cardiovascular system diseases among residents of Zhangye City, a typical western city in China. The Quasi-Poisson generalized additive regression model (GAM) in conjunction with a distributed lag nonlinear model (DLNM) was applied to estimate the association of temperature indices with CVD hospitalization rates in Zhangye City during the periods of 2015–2021. The exposure–response relationship and relative risk were discussed and stratified analyses by age and gender were conducted. We found that the hospitalization rates of cardiovascular disease (CVD) patients in Zhangye City was significantly related to different temperature indicators (MT, DTR, TCN). Both low and high MT, DTR, and TCN increased the risk of cardiovascular disease (CVD) among residents. Besides, different demographic populations exhibited distinct sensitivities to temperature conditions. Relevant authorities should devise corresponding preventive and control measures to protect vulnerable populations. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Engineering Technology is the property of Editorial Department of Electric Power Engineering Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Air pollution caused by fine particles known as PM2.5 is a significant health concern worldwide, contributing to illnesses like asthma, heart disease, and lung cancer. To address this issue, this study focused on improving air purification systems using negative ions, which can attach to these harmful particles and help remove them from the air. This paper developed a novel mathematical model based on linear differential equations to study how PM2.5 particles interact with negative ions, making it easier to design more effective purification systems. The proposed model was validated in a small, controlled space, using common urban pollutants such as cigarette smoke, incense, coal, and gasoline. These tests were conducted at different temperatures and under two levels of ion generation. The results showed that the system could remove over  99 %  of PM2.5 particles in five minutes when temperatures were low or moderate. However, at higher temperatures, the system's performance dropped significantly. This research goes beyond earlier studies by examining how temperature affects the process, which had not been fully explored before. Furthermore, this approach aligns with global sustainability goals by promoting public health, reducing healthcare costs, and providing scalable solutions for sustainable urban living. [ABSTRACT FROM AUTHOR]

Purpose: Large amplitude vibrations of a multilayered nanocomposite arch enriched by graphene nanoplatelets (GNPs) are investigated in this article. Method: The linear and nonlinear vibrational frequencies are analytically formulated for the nanocomposite arch on an elastic nonlinear support. The influence of temperature variation through the arch’s thickness is also investigated. Thermomechanical properties of the multilayered nanocomposite arch are evaluated by employing the Halpin-Tsai model of mixtures. The kinematic nonlinearity is included into the formulation within the framework of the von Kármán assumption. The kinematic relationships are valid for each layer on the basis of Reddy’s third-order shear deformation model. The equations of motion are formulated by implementing the Hamilton’s principle. A perturbation-based solution method is implemented to formulate the analytical expressions for the small- and largeamplitude vibrations. The obtained results present a comprehensive insight into the linear and nonlinear vibrations of laminated composite shallow arches in thermal field. Results: Results of this examination illustrate the effects of arch’s slenderness ratio, temperature variation, arch’s curvature ratio, weight fraction and distribution pattern of GNPs, and also foundation stiffness on the frequencies of the nanocomposite arch. Conclusion: It is seen that temperature change, radius of the arch, weight fraction of GNPs, Pattents of GNPs, stiffness of foundations are all important factors on frequencies of the composite arch. [ABSTRACT FROM AUTHOR]

With the large-scale application of electrochemical energy storage, the safety of energy storage prefabricated cabin has become increasingly prominent. The study of the differences in energy storage prefabricated cabin fires under different thermal runaway positions in the energy storage prefabricated cabin can help to design more effective monitoring and fire extinguishing systems, and to improve the safety performance of the energy storage prefabricated cabin. Therefore, it is of great significance to simulate and study the change rule of smoke dispersion and temperature evolution in energy storage prefabricated cabin under different thermal runaway positions. Based on direct numerical simulation and vortex simulation, a numerical model of lithium iron phosphate energy storage prefabricated cabin based on the size of the actual energy storage prefabricated cabin is studied, and the t2 model which is more in line with the development of the fire situation compared with the stable fire model, and investigated the change rule of the smoke dispersion and temperature inside the prefabricated cabin by simulating the fire situation with different thermal runaway positions. The simulation results demonstrate that smoke displays distinct dynamic behaviors depending on the thermal runaway positions within the energy storage prefabricated cabin. When thermal runaway positions occur closer to the bottom, smoke exhibits swifter movement and the cabin fills up in a shorter time. Additionally, as the thermal runaway positions above 1.85 meters approach the top, accompanied by significant temperature fluctuations. Notably, there is a noticeable amplification in the temperature disparity along the horizontal axis of the energy storage prefabricated cabin. Moreover, the design scheme of the fire extinguishing system for a standard energy storage prefabricated cabin with a rated capacity of 1.2 MW ·h is analyzed. This perfluorohexane fire extinguishing system, with a sprinkler intensity of 20 L/(min ·m2), a sprinkler angle of 120°and a particle size of 50 μm, can successfully controls fires and mitigates fire damage. The research results in the article can provide theoretical guidance for the distributed deployment strategy in energy storage prefabricated cabin and fire safety design of monitoring and warning devices.

The variation of temperature in the geomagnetic relative recording room can cause deviations in the relative recording data, thereby affecting the geomagnetic baseline value. This article uses observation data of annual and daily temperature differences in relative recording rooms from 40 geomagnetic reference stations in China from 2021 to 2023, and analyzes the relationship between the construction of relative recording rooms at each station and temperature changes based on the data results. The research results show that about 70% of the total statistics are stations have an annual temperature difference of less than 10℃ in the relative recording room, and about 85% of stations have a daily temperature difference of less than 0.3 ℃. The findings suggest that a well-insulated geomagnetic relative recording room has smaller impact on temperature. Fully underground recording rooms exhibit the best insulation performance, followed by the insulation effect of the semi underground type recording room. Conversely, fully above-ground structures have poorer insulation, although a thicker insulation layer can still meet regulatory requirements. In the construction or renovation of relative recording rooms, priority should be given to selecting a fully underground structure for geomagnetic stations with significant annual temperature changes. For semi-underground recording rooms or fully above-ground buildings, increasing the thickness of the insulation layer is recommended.

Abstract Background Climate change is driving increased extreme weather events that can impact ecology by moderating host–pathogen interactions. To date, few studies have explored how cold snaps affect disease prevalence and proliferation. Using the Daphnia magna–Ordospora colligata host-parasite system, a popular model system for environmentally transmitted diseases, the amplitude and duration of cold snaps were manipulated at four baseline temperatures, 10 days post-exposure, with O. colligata fitness recorded at the individual level. Results Cold snaps induced a fivefold increase or a threefold decrease in parasite burden relative to baseline temperature, with complex nuances and varied outcomes resulting from different treatment combinations. Both amplitude and duration can interact with the baseline temperature highlighting the complexity and baseline dependence of cold snaps. Furthermore, parasite fitness, i.e., infection prevalence and burden, were simultaneously altered in opposite directions in the same cold snap treatment. Conclusions We found that cold snaps can yield complicated outcomes that are unique from other types of temperature variation (for example, heatwaves). These results underpin the challenges and complexity in understanding and predicting how climate and extreme weather may alter disease under global change.

Carbon dioxide (CO2 ${\text{CO}}_{2}$), an important trace species that is gradually increasing in the atmosphere due to anthropogenic activities, causes enhanced warming in the lower atmosphere. The increased concentration of CO2 ${\text{CO}}_{2}$ in the upper atmosphere results in enhanced radiative cooling rates leading to the contraction of the upper atmosphere. Due to its long lifetime and large vertical gradient, CO2 ${\text{CO}}_{2}$ concentration is also influenced by large dynamic events. We report a startling case of variability in CO2 ${\text{CO}}_{2}$ density and its infrared radiative cooling rates in the mesosphere and lower thermosphere during a major sudden stratospheric warming (SSW) event. A counter‐intuitive connection between CO2 ${\text{CO}}_{2}$ density and resulting CO2 ${\text{CO}}_{2}$ radiative cooling has been observed during the 2009 major SSW event. The behavior of CO2 ${\text{CO}}_{2}$ cooling rates during such a dramatic events draws attention to our current understanding of CO2 ${\text{CO}}_{2}$ infrared cooling variation and its connection to changes in CO2 ${\text{CO}}_{2}$ concentration. The significance of temperature and atomic oxygen variability in the observed cooling patterns despite changes in CO2 ${\text{CO}}_{2}$ concentration, is also highlighted. Plain Language Summary: CO2 ${\text{CO}}_{2}$ is a greenhouse gas that is gradually increasing in the earth's atmosphere due to anthropogenic activities causing variations in the thermal structure of the atmospheric layers. The collision of CO2 ${\text{CO}}_{2}$ with other atmospheric constituents excites it in the vibrational state, which radiates the 15 μ ${\upmu }$m band, therefore converting the kinetic energy into radiation and engendering cooling. Many dynamical events, such as sudden stratospheric warming events, influence the typical structure of the middle atmosphere (∼ ${\sim} $30–110 km), including the transport of trace species such as CO2 ${\text{CO}}_{2}$. These events occur when vertically propagating planetary waves deposit momentum on breaking and lead to a change in circulation, primarily in the stratosphere. We have studied the changes that occurred in the CO2 ${\text{CO}}_{2}$ density and CO2 ${\text{CO}}_{2}$ infrared radiative cooling in the mesosphere and lower thermosphere at 60° ${}^{\circ}$–70° ${}^{\circ}$N during the 2008–2009 winter. The CO2 ${\text{CO}}_{2}$ density shows variations in the polar mesosphere during the SSW event. These variations in CO2 ${\text{CO}}_{2}$ density are due to circulation changes, causing an ascent (descent) of CO2 ${\text{CO}}_{2}$ rich (poor) air‐mass into higher altitudes during (after) these events. The effect of CO2 ${\text{CO}}_{2}$ variability on the CO2 ${\text{CO}}_{2}$ radiative cooling has also been analyzed during the major SSW event, and it is found that atomic oxygen, in addition to temperature variation, plays a crucial role in the CO2 ${\text{CO}}_{2}$ radiative cooling changes. Key Points: The circulation changes during a major SSW event can cause an increase in mesospheric CO2 ${\text{CO}}_{2}$ density during peak warming periodThe CO2 ${\text{CO}}_{2}$ infrared radiative flux is found to be anticorrelated with CO2 ${\text{CO}}_{2}$ density during the main phase of SSW eventThe CO2 ${\text{CO}}_{2}$ 15 μ $\mu $m radiative cooling is dynamically influenced by the changes in temperature and atomic oxygen density in addition to the change in CO2 ${\text{CO}}_{2}$ abundance [ABSTRACT FROM AUTHOR]

Salt expansion and frost heave are the main diseases of salted frozen soil roadbeds. Salt swelling and frost heave disease are closely related to the salted soil water–salt migration, temperature variation, and salt crystallization amount change. This article establishes a coupled model of water, heat, and salt fields based on the capillary model and the unfrozen water characteristic curve. The study shows that the different initial moisture contents have minimal effects on the location of soil salt migration and aggregation. The different initial salt concentrations have a substantial effect on the soil water–salt migration aggregation position; when the concentration of sodium sulfate increases, different from chloride saline soils, the position of the freezing front fluctuates up and down over time. The water–salt migration and aggregation are smaller in the closed condition, where they are reduced by 38% and 20%, respectively. [ABSTRACT FROM AUTHOR]

AbstractThis paper presents a static analysis of large deflection behavior in functionally graded magneto-electro-elastic porous (FG-MEEP) cylindrical shells using the geometric fully nonlinear finite element (FE) method. The governing equations are derived based on the first-order shear deformation theory (FOSD) and the strain-displacement relationship considering large rotations. A nonlinear dynamic model is developed employing the Hamiltonian principle. Four gradient models of temperature variation along the thickness are constructed, such as uniform, linear, sinusoidal and heat conduction. Moreover, the porosity effects of FG-U, FG-V, FG-O and FG-X distributions are taken into account. The accuracy and efficiency of the proposed model are verified by comparing with the results of existing literature and commercial software. The subsequent extensive research is conducted to investigate the influence of various parameters on the mechanical response of the FG-MEEP structure. It is concluded that adopting the large rotation theory (LRT) can yield more precise outcomes for structures experiencing significant deformations under thermal environments, providing valuable insights for future research on FG-MEEP structures. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Earthquake Sciences is the property of China Earthquake Administration, Institute of Geophysics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Climate change is driving increased extreme weather events that can impact ecology by moderating host–pathogen interactions. To date, few studies have explored how cold snaps affect disease prevalence and proliferation. Using the Daphnia magna–Ordospora colligata host-parasite system, a popular model system for environmentally transmitted diseases, the amplitude and duration of cold snaps were manipulated at four baseline temperatures, 10 days post-exposure, with O. colligata fitness recorded at the individual level. Results: Cold snaps induced a fivefold increase or a threefold decrease in parasite burden relative to baseline temperature, with complex nuances and varied outcomes resulting from different treatment combinations. Both amplitude and duration can interact with the baseline temperature highlighting the complexity and baseline dependence of cold snaps. Furthermore, parasite fitness, i.e., infection prevalence and burden, were simultaneously altered in opposite directions in the same cold snap treatment. Conclusions: We found that cold snaps can yield complicated outcomes that are unique from other types of temperature variation (for example, heatwaves). These results underpin the challenges and complexity in understanding and predicting how climate and extreme weather may alter disease under global change. [ABSTRACT FROM AUTHOR]

This study investigates the effects of a back plate preheating assistance system and deep rolling (DR) on axial force and tunnel defects during friction stir welding (FSW). Different preheating configurations—advancing side (AS), retreating side (RS), and both sides—were examined to evaluate their impact on axial force reduction, temperature distribution, and defect minimization. Axial force measurements were taken using a dynamometer, and temperature histories were recorded with a thermal camera. The results demonstrate that a preheating temperature of 200 °C is optimal, reducing axial force by 30.24% and enhancing material flow. This temperature also facilitated deeper tool penetration, especially when preheating was applied to both sides. Preheating on the AS resulted in the smallest tunnel defects, reducing defect size by 80.15% on the RS and 96.91% on the AS compared to the non-preheated condition. While DR further reduced tunnel defects, its effectiveness was limited by the proximity of defects to the surface. These findings offer significant insights for improving the FSW process. [ABSTRACT FROM AUTHOR]

To study the temperature and stress variation laws of fast-hardening concrete for bridge deck paving,finite element simulation was employed to model the temperature and stress changes of fast-hardening concrete at different ages,and the results were compared and analyzed with the measured data from sensing optical cables to verify the accuracy of the finite element simulation. The results indicate that the temperature cracking index for all ages is greater than 1.5,and the tensile strength of fast-hardening concrete at 6 h can resist the tensile stress caused by hydration heat,possessing a certain crack resistance capability. For the fast-hardening concrete in bridge deck paving,the bottom layer,middle layer,and surface layer reach their peak temperatures approximately 4h after pouring,with the highest temperatures being 39,37,32,respectively,after which the temperature in each layer gradually decreases over time. Within the first 0 to 3d,as the age increases,the strain in the middle and bottom layers of the fast-hardening concrete for bridge deck paving gradually increases,reaching a peak at 3 d,then decreasing by 7 to 28 d. The finite element simulation calculations are basically consistent with the measured values,which can provide a reference for the crack prevention and construction process optimization of fast-hardening concrete in emergency repairs of large scale bridge deck pavement. [ABSTRACT FROM AUTHOR]

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However, it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network shutdowns, which could potentially trigger hydrate formation, the installation of methanol injection connectors remains necessary to ensure production safety. [ABSTRACT FROM AUTHOR]

Soil moisture variation plays a key role in maintaining the engineering properties of soils. One of the main factors that impact the soil moisture content is the temperature, which has a strong impact to change the initial or design moisture and results in significant soil volume changes. This study aims to investigate the effects of temperature on the performance of enzymatically stabilised soils. The enzyme used in this study is Eko-soil and the soil used is clayey silt of low plasticity (ML). The mechanical behaviour was first assessed through the unconfined compression strength and weight measurements based on samples exposed to a series of operational temperatures. X-ray μCT tomography images were then used to assess the microstructure. Porosity, size and geometrical shape of the pores were analysed at elevated temperatures. Results revealed that the enzyme is effective in maintaining the initial pore structure under the tested temperature range. [ABSTRACT FROM AUTHOR]

Enhanced geothermal systems (EGSs) are expected to be one of the most promising methods of supplying energy to meet the world's increasing energy demand. However, little attention has been paid to the influence of the number of production wells on the heat extraction performance of an EGS. A series of numerical simulations is organized in this work with three cases: Case 1 (one production well), Case 2 (two production wells), and Case 3 (three production wells). The results indicate that a slight temperature difference exists among the three simulation cases at the planes X-Y (Z = 0) and Y-Z (X = 0), while Case 1 ensures a greater cooling area, and the more production wells, the smaller the cooling area during the heat extraction in plane X-Z (Y = 0). In addition, the continuous injection of cooling water from the injection well and its arrival at different reference points enable the temperature at each point to declining with a variable amplitude of variation. This work also sets an efficiency (ef) to investigate the temperature variation in the EGS, where Case 1 exhibits a similar variation as Case 2, which is also similar to Case 3. It is hoped that this work will play a guiding role in EGS-related exploration and exploitation. [ABSTRACT FROM AUTHOR]

Summary: In this study, the effect of short‐term storage at different temperatures (0, 4 and −8 °C) on the quality of Antarctic krill was investigated using the main quality indicators as a reference, combined with electronic nose and untargeted metabolomics. Antarctic krill stored at lower temperatures (−8 °C) were of better quality and had a flavour similar to that of the original Antarctic krill. Metabolomics analyses showed that differential metabolites (DMS) were more abundant in Antarctic krill at higher temperatures (4 °C), with sixty‐five metabolites having reduced expression and forty‐five metabolites having increased expression; Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that amino acid metabolism and nucleotide metabolism pathways were the Five DMS, including α‐ketoglutarate, glutamate, succinate, sucrose and glutarate, can be used as potential biomarkers to monitor quality changes during short‐term storage of Antarctic krill. In addition, the association between quality indicators and differential metabolites remains to be explored. [ABSTRACT FROM AUTHOR]

The failure of MOSFET at ultra-small dimensions has directed researchers to investigate alternate FETs. Vast applications and the compactness of integrated circuits have made the investigation of FETs against variation in temperature and lattice heating very crucial; hence, in this work, the effect of variation in temperature and lattice heating on the characteristics of a charge plasma based tunnel field-effect transistor is analyzed. To enhance tunnelling probability, SiGe composite is used at the source electrode, and silicon is used across the drain terminal. To overcome the fabrication issues faced by doped TFET, charge plasma technique is utilised to create a doping profile. Variation is examined on different device, analog and linearity parameters. For investigation, temperature is varied from 200 to 400 K, and it was detected that operation at a lower temperature results in better ION/IOFF characteristics but degrades the linearity characteristics of the device. At 200 K, lowest IOFF of order 10-19A/µm and high ION/IOFF of 4.66 × 1012 is obtained. Work done also illustrates that the effect of lattice heating becomes dominant at voltages greater than 1.5 V. Lattice hating improves analog characteristics by a factor of 1.02 but degrades linearity parameters such as VIP3 and IIP3 by 0.27dBm and 0.03dBm respectively. [ABSTRACT FROM AUTHOR]

Terahertz (THz) spectroscopy has demonstrated significant potential for substance detection due to its low destructiveness and due to the abundance of molecular fingerprint absorption signatures that it contains. However, there is limited research on the fingerprint detection of substances at different temperatures. Here, we propose a THz metamaterial slit array sensor that exploits localized surface plasmons to enhance the electric field within the slit. The transmission peak frequency can be modulated via temperature adjustments. This method enables the detection of molecular absorption characteristics at multiple spectral frequency points, thereby achieving a specific and highly sensitive detection of characteristic analyte fingerprint spectra. Additionally, the sensor supports the detection of substances at multiple temperatures and sensitively identifies changes in their absorption properties as a function of temperature. Our research has employed temperature variation to achieve a highly sensitive and specific detection of trace analytes, offering a new solution for THz molecular detection. [ABSTRACT FROM AUTHOR]

IntroductionEpidemiological evidence suggests cerebrovascular disease (CVD) incidence is correlated to meteorological conditions. However, research on the primary meteorological factors influencing the incidence of CVD and their influence thresholds in low-latitude mountainous regions remains insufficient. We aimed to investigate the association between meteorological conditions and CVD occurrence in Guizhou province.MethodsUtilizing daily incidence cases for CVD alongside concurrent meteorological data from four microclimate representative stations in Guizhou Province during 2021-2022, we firstly performed random forest and decision tree analysis to identify the significant meteorological factors influencing the incidence of CVD, and then we applied distributed lag non-linear model (DLNM) to assess the effect of meteorological factors on CVD incidence.ResultsCritical meteorological factors associated with CVD incidence include diurnal temperature range (DTR), temperature change between neighboring days (TCN), diurnal pressure range (DPR), pressure change between neighboring days (PCN), and minimum temperature. The risk of CVD incidence markedly increased with narrow DTR, positive TCN, and colder conditions. The thresholds of minimum temperature and TCN droped with the decrease of annual average temperature in microclimate zone. In the middle subtropical region of Jiangkou, the northern subtropical region of Xishui, and the warm temperate region of Shuicheng, there was a risk of CVD when the minimum temperature falled below 12.2°C, 10.7°C, and 6.7°C, respectively. When TCN exceeded the critical threshold (0.2°C in Shuicheng, 0.3°C in Xishui, and 0.4°C in Jiangkou and Ceheng), the risk of CVD incidence increased linearly. DPR and PCN displayed varied thresholds across different microclimate without consistent patterns. DPR in middle subtropical region of Jiangkou and warm temperate region of Shuicheng played a protective role, while the risk of the disease increased linearly when DPR was lower than 3.2 hPa and 2.7 hPa in south subtropical region of Ceheng and north subtropical region of Xishui, respectively. The short-term effects within 5 days with small DTR and narrow positive TCN were more obvious. The thresholds and lag times of other meteorological environmental factors remained indistinct in the four microclimate zones.DiscussionOur findings delineated the common characteristics of the effect on the incidence of CVD of meteorological environments in various microclimate zones, and clarified the influence of minimum temperature and TCN exhibited spatial heterogeneity, Which may be assistance for meteorological risk forecasting in CVD prevention and control.

Lithium-ion batteries are essential to modern technology, requiring accurate estimation of the state of charge (SOC) for optimal performance. Traditional methods such as Coulomb Counting (CC) are ineffective in the face of temperature variations, leading to inaccuracies in SOC estimation, which in turn cause obvious deformation of hysteresis curves. To address this, this paper introduces a novel method called Polynomial Fit State of Charge (FPSOC), for effective SOC estimation. This method incorporates a fifth-degree polynomial fitting that accounts for a wide range of temperature variations (from -10 °°C to +80 °°C), a feature that, according to the authors, has not been offered by all previously published methods. A series of simulation tests using the MATLAB/Simulink tool are conducted under various temperature profiles to evaluate the effectiveness of the FPSOC method. The results demonstrate the notable superiority of the FPSOC model compared to the CC method, with a significantly reduced RMSE of only 0.93 % compared to 6.77 % of the CC model. Particularly effective at low SOC levels (30 %), the FPSOC model demonstrates precision up to six times higher compared to the CC model. Additionally, when evaluated against other recent SOC estimation techniques such as CM, RLSF, EKF, DST, BBDST, ASMO, LPM_H, LSTM-SA Group A and B, and baseline ECM-ID, The FPSOC method proves extremely accurate, with the lowest average error under different temperature conditions.

Salt expansion and frost heave are the main diseases of salted frozen soil roadbeds. Salt swelling and frost heave disease are closely related to the salted soil water–salt migration, temperature variation, and salt crystallization amount change. This article establishes a coupled model of water, heat, and salt fields based on the capillary model and the unfrozen water characteristic curve. The study shows that the different initial moisture contents have minimal effects on the location of soil salt migration and aggregation. The different initial salt concentrations have a substantial effect on the soil water–salt migration aggregation position; when the concentration of sodium sulfate increases, different from chloride saline soils, the position of the freezing front fluctuates up and down over time. The water–salt migration and aggregation are smaller in the closed condition, where they are reduced by 38% and 20%, respectively.

The revolutionary future of proton-exchanging membrane fuel cells (PEMFC) has recently garnered a great deal of excitement, as has their green energy source. Maximizing the production of electricity from PEMFC is crucial to maintaining effectiveness. This research article thoroughly analyzes a research study using a strategy known as MPPT, or maximum power point tracking that uses the neuro-fuzzy method for PEMFC operating under diverse temperatures, pressures, and joining constraints. The neuro-fuzzy controller cleverly regulates the point of maximal operation of a hydrogen fuel cell system, allowing exact adherence to the highest possible power scale. According to simulation results, the neuro-fuzzy MPPT technique improves PEMFC validity across a wide range of operating scenarios.

Octreotide is the first synthetic peptide hormone, consisting of eight amino acids, that mimics the activity of somatostatin, a natural hormone in the body. During the past decades, advanced instrumentation and crystallographic software have established X-Ray Powder Diffraction (XRPD) as a valuable tool for extracting structural information from biological macromolecules. The latter was demonstrated by the successful structural determination of octreotide at a remarkably high d-spacing resolution (1.87 Å) (PDB code: 6vc1). This study focuses on the response of octreotide to different humidity levels and temperatures, with a particular focus on the stability of the polycrystalline sample. XRPD measurements were accomplished employing an Anton Paar MHC-trans humidity-temperature chamber installed within a laboratory X’Pert Pro diffractometer (Malvern Panalytical). The chamber is employed to control and maintain precise humidity and temperature levels of samples during XRPD data collection. Pawley analysis of the collected data sets revealed that the octreotide polycrystalline sample is remarkably stable, and no structural transitions were observed. The compound retains its orthorhombic symmetry (space group: P212121, a = 18.57744(4) Å, b = 30.17338(6) Å, c = 39.70590(9) Å, d ~ 2.35 Å). However, a characteristic structural evolution in terms of lattice parameters and volume of the unit cell is reported mainly upon controlled relative humidity variation. In addition, an improvement in the signal-to-noise ratio in the XRPD data under a cycle of dehydration/rehydration is reported. These results underline the importance of considering the impact of environmental factors, such as humidity and temperature, in the context of structure-based drug design, thereby contributing to the development of more effective and stable pharmaceutical products.

This paper examines the effect of temperature variation on the surface triangular grating of the surface plasmon polariton (SPP) on the effectiveness of the entire array of silicon thin-film solar cells. Thin-film solar cells' optical and electrical characteristics are examined using the electromagnetic and semiconductor models. The 3D Multiphysics simulator is used to present this study. The MATLAB/SIMULINK model based on mathematical formulas is developed to simulate the entire array of solar cells with thin films. This approach is suggested for quickly simulating the thin-film array. The presented model was applied on thin-film solar cells with and without SPP depending on the complete cell parameters from the COMSOL Multiphysics model. The triangle's SPPs accomplish a 14.76% efficiency increase of 1.07% over a solar cell without SPPs. [ABSTRACT FROM AUTHOR]

Octreotide is the first synthetic peptide hormone, consisting of eight amino acids, that mimics the activity of somatostatin, a natural hormone in the body. During the past decades, advanced instrumentation and crystallographic software have established X-Ray Powder Diffraction (XRPD) as a valuable tool for extracting structural information from biological macromolecules. The latter was demonstrated by the successful structural determination of octreotide at a remarkably high d-spacing resolution (1.87 Å) (PDB code: 6vc1). This study focuses on the response of octreotide to different humidity levels and temperatures, with a particular focus on the stability of the polycrystalline sample. XRPD measurements were accomplished employing an Anton Paar MHC-trans humidity-temperature chamber installed within a laboratory X'Pert Pro diffractometer (Malvern Panalytical). The chamber is employed to control and maintain precise humidity and temperature levels of samples during XRPD data collection. Pawley analysis of the collected data sets revealed that the octreotide polycrystalline sample is remarkably stable, and no structural transitions were observed. The compound retains its orthorhombic symmetry (space group: P212121, a = 18.57744(4) Å, b = 30.17338(6) Å, c = 39.70590(9) Å, d ~ 2.35 Å). However, a characteristic structural evolution in terms of lattice parameters and volume of the unit cell is reported mainly upon controlled relative humidity variation. In addition, an improvement in the signal-to-noise ratio in the XRPD data under a cycle of dehydration/rehydration is reported. These results underline the importance of considering the impact of environmental factors, such as humidity and temperature, in the context of structure-based drug design, thereby contributing to the development of more effective and stable pharmaceutical products. [ABSTRACT FROM AUTHOR]