Effect Of Temperature Research Articles

A Unified Interpretation of Variability in Precipitation Isotope Ratios

Abstract Several mechanisms have been proposed to explain why the isotope ratios of precipitation vary in space and time and why they correlate with other climate variables like temperature and precipitation. Here, we argue that this behavior is best understood through the lens of radiative transfer, which treats the depletion of atmospheric vapor transport by precipitation as analogous to the attenuation of light by absorption or scattering. Building on earlier work by Siler et al., we introduce a simple model that uses the equations of radiative transfer to approximate the two-dimensional pattern of the oxygen isotope composition of precipitation (δp) from monthly mean hydrologic variables. The model accurately simulates the spatial and seasonal variability in δp within a state-of-the-art climate model and permits a simple decomposition of δp variability into contributions from gradients in evaporation and the length scale of vapor transport. Outside the tropics, δp is mostly controlled by gradients in evaporation, whose dependence on temperature explains the positive correlation between δp and temperature (i.e., the temperature effect). At low latitudes, δp is mostly controlled by gradients in the transport length scale, whose inverse relationship with precipitation explains the negative correlation between δp and precipitation (i.e., the amount effect). This suggests that the temperature and amount effects are both mostly explained by the variability in upstream rainout, but they reflect distinct mechanisms governing rainout at different latitudes. Significance Statement The isotopic composition of precipitation has long been used to make inferences about past climates based on its observed relationship with precipitation in the tropics and with temperature at higher latitudes. These relationships—known as the “amount effect” and “temperature effect,” respectively—have been attributed to many different mechanisms, most of which are thought to operate at either high or low latitudes but not both. Here, we present a unified framework for interpreting the isotope variability that can explain the latitude dependence of the temperature and amount effects despite making no distinction between high and low latitudes. Although our results are generally consistent with certain interpretations of the amount effect, they suggest that the temperature effect is widely misunderstood.

Influence of alginate extraction conditions from the brown seaweed Dictyota mertensii on the functional properties of a novel glycerol plasticized alginate film.

Influence of alginate extraction conditions from the brown seaweed Dictyota mertensii on the functional properties of a novel glycerol plasticized alginate film.

Effect of Weather Variables on the Inoculum of Diaporthe amygdali Causal Agent of Twig Canker and Shoot Blight in Almond Orchards.

Diaporthe amygdali is the causal agent of twig canker and shoot blight disease on almond. The main objective of this study was to elucidate the effect of weather variables on the D. amygdali inoculum in almond orchards in Mediterranean conditions. For that purpose, a quantitative PCR (qPCR) assay for the detection and quantification of D. amygdali was developed. This methodology was used to detect and quantify inoculum of D. amygdali in spore traps placed at two almond orchards from different locations in two growing seasons (2019 to 2020 and 2020 to 2021). Weather variables were also recorded. Two-part Hurdle models, which include a qualitative part (Bernoulli), with a binary response, and a quantitative part (Gamma), were used to study the relationships of DNA concentration of D. amygdali on the traps with weather variables. The temperature effect was related to the daily thermal amplitude; narrower thermal ranges increased DNA detection, while wider thermal ranges reduced DNA concentration. Days with average relative humidity higher than 80% had a negative effect on the concentration of D. amygdali DNA. Rainfall had a positive influence on both parts of the model, confirming the contribution of precipitation in the abundance of inoculum. Finally, wind speed positively influenced both parts of the models in both growing seasons. The relationships between weather variables and inoculum of D. amygdali will assist to develop a decision support system to optimize the management of twig canker and shoot blight disease on almond.

Concrete dam deformation prediction model considering the time delay of monitoring variables

Concrete dam structures respond to various influencing factors with complex nonlinear characteristics and notable time lags. Deformation serves as a crucial monitoring metric, providing a direct indication of the structural response of these dams. An effective deformation analysis and prediction model is essential for accurately assessing the health of concrete dam structures. Current deformation prediction models have limitations in simulating time-delay effects. This study introduces time-shifted correlation coefficients and time-delayed transfer entropy to analyze the direction of information transmission and the time delays among environmental temperature, dam body temperature, and deformation monitoring variables. A methodology is proposed to determine the dimensions of temperature factors and their respective time delays. Utilizing a long short-term memory (LSTM) neural network integrated with Dropout regularization, a concrete dam deformation prediction model that accounts for the time delay effect of environmental temperature is developed. The results demonstrate that the proposed deformation prediction model offers superior fitting accuracy and predictive capability, effectively elucidating how environmental and dam body temperatures influence dam deformation.

Optical fibers performance parameters management under the control of spectral functional light sources with various wavelength windows and thermal effects

Abstract This paper has clarified the high speed performance signature of single-mode/multimode graded index silica-doped fibers in point to point link transceiver communication system. Fiber signal attenuation is studied versus ultraviolet wavelength region and different germanium dopant ratios added to silica fibers in point to point link. The fiber signal attenuation is also clarified versus near infrared wavelength region and different germanium dopant ratios added to silica fibers in point to point link. Fiber scattering loss is demonstrated against spectral operating wavelength region and different thermal effects of fiber temperature in point to point link. The modal fiber dispersion is investigated clearly and clarified in relation to fiber numerical aperture at different relative refractive index difference at operating spectral wavelength of 1,550 nm and 1,300 nm near infrared regions.

Carbonization Tuned Core‐Shell Fe3O4@C Nanostructures with Enhanced Electromagnetic Wave Absorption

AbstractWith the advent of high‐power electronic devices, communication satellites, and military radar systems, electromagnetic (EM) waves have caused significant pollution. In this work, hollow Fe3O4@C (H‐FO@C) composites are synthesized by employing an in situ polymerization and carbonization treatment. Effects of carbonization temperature on electromagnetic wave absorption of core‐shell structured H‐FO@C composites are symmetrically analyzed, and the impedance matching and attenuation ability are improved significantly by controlling carbonization temperature. The reflection loss (RL) and effective absorption bandwidth (EAB) of H‐FO@C composites carbonized at 650 °C are improved to −51.85 dB and 5.36 GHz (thickness 2.1 mm), respectively. When the thickness of composites increases from 2.1 to 2.4 mm, the EAB reaches 6.24 GHz. According to CST Studio Suit, the radar cross section (RCS) reduction value can be 24.26 dB m2 for H‐FO@C composites. Both experiment and simulation results confirm that the H‐FO@C composites possess excellent EWA performance. This work provides a new way for advancing EWA materials.

The Effect of Temperature and Current on the Insulation Performance of PE and PVC Power Cables: A Finite Element Approach

In this study, a numerical simulation was used to evaluate the insulation performance of polyethylene (PE) and polyvinyl chloride (PVC) under varied environmental and electrical conditions. Tests were conducted at temperatures of 22 °C and 55 °C, with current levels of 40 A and 60 A, examining key parameters such as electric field intensity, current density, and Joule heating. The results show that, under lower temperature and current conditions, PE demonstrates greater current capacity but suffers from increased Joule heating and energy loss. Conversely, PVC provides more stable insulation with lower energy dissipation. At higher temperatures and currents, PE experiences significant electrical stress and thermal loading, increasing the risk of overheating, while PVC maintains consistent performance. These findings offer valuable guidance for selecting optimal insulation materials in power distribution systems.

Radiochromic film dosimeter based on povidone-iodine for gamma dosimetric applications

Abstract A novel radiochromic polymeric film dosimeter based on povidone-iodine was prepared. The spectrophotometric properties of unirradiated and gamma-irradiated films were investigated using a UV–Vis spectrophotometer. This study proved that the polymeric films of PVP-I/PVA can be used as gamma radiation dosimeters in the dose range from 1 to 25 kGy as their color appears and intensity increases with increasing gamma radiation absorbed dose peaking at λ max = 295 nm and 365 nm. The stability of the color of the polymeric films, effects of temperature and relative humidity were measured. These film dosimeters can be applied in many fields as they have many advantages.

Experimental Analysis of Mechanical and Physical Properties of Hexagonal Paver Block using Plastic Polymer as a Binder

Nepal faces significant challenges in solid waste management, especially with non-biodegradable plastic waste. Recycling and reusing plastic waste as construction material can help reduce its impact significantly. This study evaluates the mechanical and physical properties of paver blocks bonded with waste polymer, specifically Polyethylene Terephthalate (PET), by varying the PET-to-sand proportions. Fifty-four hexagonal block samples were made by applying 100 bars of pressure in a hydraulic press machine. PET and sand were mixed in the following proportions: 15:85, 20:80, 25:75, 30:70, 35:65, and 40%. The compressive strength after 7 days and 14 days varied between 15.51 MPa to 33.47 MPa and 15.72 MPa to 35.54 MPa, respectively. And the compressive strength ranged between 18.27 MPa and 33.73 MPa after 14 days, with the temperature effect. With increasing PET proportion, the bulk density varied from 1886.772 kg/m3 to 2144.974 kg/m3. And the water absorption varied from 1.42 to 4.46. The outcome shows that the compressive strength of paver blocks rises with an increase in PET percentage up to 25%, after which the compressive strength decreases. When the proportion of PET rises, bulk density and water absorption both falls.

Traceable Uncertainty of Exhaust Flow Meters Embedded in Portable Emission Measurement Systems

Portable emissions measurement systems (PEMS) are used in the type approval tests of diesel- and petrol-fuelled light-duty vehicles. PEMS measure the amount of pollutants emitted during on-road, real driving, and testing of a vehicle. PEMS are comprised of gas analyzers, which measure the concentration of pollutants in the exhaust gas, and exhaust flow meters (EFMs), which measure the amount of emitted exhaust gas during an on-road test. With the adoption of the real driving emissions (RDE) legislation in 2016–2018, usage of PEMS during on-road tests became mandatory in the European Union for the type approval of light-duty vehicles. For accurate assessment of pollutant emissions, SI-traceable calibration of PEMS equipment is required, which is typically performed under the carefully controlled conditions of a calibration laboratory. However, when using the PEMS equipment in real driving conditions on the road, additional factors contribute to the measurement uncertainty with respect to the laboratory measurement uncertainty as established during the SI-traceable calibration. For this reason, the RDE prescribes the usage of conformity factors to account for additional measurement uncertainty in real-driving-type approval tests. The pollutant emissions measurements are a combination of the gas analyzer measurements and the EFM flow measurement. The EFM measurement uncertainty contributes strongly to the overall pollutant emissions measurement uncertainties. Further, the EFM measurement uncertainty in on-road conditions is not fully characterized. Consequently, SI-traceable, quantitative information on on-road factors affecting measurement uncertainty is needed. Important factors potentially affecting EFM measurement uncertainty are exhaust flow transients, flow pulsations, gas composition, temperature effects, and flow meter drift. For an improved understanding of representative, SI-traceable, EFM measurement uncertainty (I) a generic uncertainty analysis is presented, which is obtained from performing an uncertainty analysis on state-of-the-art knowledge stemming from literature. This is followed by (II) presenting quantitative and partly traceable measurement results of experiments dedicated to the assessment of uncertainty from potentially significant factors contributing to the overall measurement uncertainty of the EFM in on-road conditions. Experimental results indicate that the EFM can match the (laboratory) accuracy limits as defined in the RDE. Other experimental results indicate that specific potential on-road conditions can affect the EFM such that the resulting overall measurement uncertainty exceeds the limit from the employment of the RDE-prescribed conformity factor.

A functional mixed effect model approach to explore regional climate patterns in Bangladesh

As global warming intensifies, localized climate studies have become essential to understanding the nuanced impacts of climate change, particularly in vulnerable countries like Bangladesh. While global climate models highlight general trends, the detailed temporal and regional variations within countries remain underexplored. Bangladesh, with its susceptibility to climate extremes, requires precise methodologies to analyze short-term climate projections and inform adaptive strategies. This study utilizes the Functional Linear Mixed-effects Model (FLMM), a sophisticated statistical framework for analyzing functional data with repeated observations, to investigate the effects of temporal and regional variations of the effect of daily temperature on annual precipitation across Bangladesh from 2008 to 2022. The population slope function βt was represented using 35 Fourier basis functions, while individual-level variability bi(t) was captured using 25 basis functions. A Residual Maximum Likelihood with Expected Maximisation algorithm (REML-based EM algorithm) estimated fixed effects and random effect variance parameters. The findings reveal significant district-wise variations in rainfall estimates, influenced by daily temperature patterns over time. Additionally, a functional autoregressive model (FAR(1)) highlights the influence of one-year rainfall differences on precipitation projections for the subsequent year. By capturing localized variability and addressing uncertainties, the model provides valuable insights for short-term climate forecasting, resource prioritization, and adaptive planning. Such insights can inform targeted interventions, including flood mitigation measures, drought-resistant agriculture, and dynamic resource allocation for climate adaptation strategies in Bangladesh.

The effect of changing the temperature of the vacuum carburizing process on the layer properties of steels used in the automotive industry

Abstract This study examines the effects of vacuum carburizing temperatures ranging from 960 to 1000 °C on the properties of 16MnCr5 and 20NiMoCr6-5 steels, which are frequently employed in automotive manufacturing. Utilizing ALD ModulTherm equipment, controlled chemical heat treatment was conducted, achieving carbon saturation depths of 0.5 to 0.8 mm. The investigation focuses on critical parameters such as grain size, microstructure, and microhardness profiles to elucidate how these properties are influenced by temperature variations. The results demonstrate that carburizing temperature significantly alters the mechanical properties of the steels, particularly affecting microhardness and grain structure. Higher carburizing temperatures enhance microhardness but may also lead to undesirable coarsening effects in the austenitic grain structure. These findings highlight the importance of optimizing carburizing temperatures to improve the durability and overall functionality of automotive components.

Ba‐Modified Bi–Na–Sr Titanate: Exploring Structural, Dielectric, and Electrocaloric Properties for Cooling Applications

The present work reports the structural, dielectric, and electrocaloric properties of Ba‐doped (Bi0.5Na0.5)0.8Sr0.2TiO3 (BNST) synthesized by the solid‐state reaction route. Rietveld refined X‐ray diffraction data is used to analyze the influence of Ba doping on the lattice parameters, crystallite size, and lattice strain of BNST. The dielectric characteristics of the Ba‐doped BNST samples are analyzed in terms of complex permittivity, AC conductivity, and complex impedance. The dynamic properties of dipoles and the conduction charges are investigated from the frequency‐dependent (100 Hz–1 MHz) dielectric response. Electrocaloric properties are assessed by the indirect method using the Maxwell equation. Polarization of pure and Ba‐substituted BNST varies in a complex manner as a function of temperature leading to positive and negative electrocaloric effects in different temperature ranges within room temperature‐160 °C, beneficial for exploiting the increasing and decreasing, both, cycles of the applied electric field for producing cooling effect. The dipolar entropy is consistent with the literature.

Effect of heating temperature on pore structure of briquette coal using SEM, NMR, N2/CH4 adsorption-desorption analyses

The development of briquettes capable of effectively replacing raw coal samples in physical simulation experiments is crucial for coal mine gas disaster prevention. We invented a new method for preparing briquette coal (BC), and studied how the heating temperature changed its pore structures using scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), the low temperature liquid nitrogen adsorption test (LTNAT), and the CH4 adsorption-desorption test. We found that with an increase in heating temperature, SEM analysis showed that the surface roughness of the coal body increased, and the pores gradually changed from non-developed to large pores. NMR analysis showed that the content of briquette micropores decreased, and that of the macropores increased. Furthermore, at 300 °C, the cumulative total porosity of the BC was less than that of other coal samples. In the LNLDT test, all coal samples had inverted “S” type and IV type isothermal adsorption curves, with the minimization of peak values of pore volume and specific surface area occurring at 600 °C; D1 gradually decreased, and D2 gradually increased. The CH4 adsorption-desorption test showed that a higher preparation temperature during the adsorption process resulted in a greater adsorption capacity of briquette to CH4. A Langmuir model was used to fit the adsorption data, where the adsorption constant “a” of coal increased and “b” decreased. Our results provide a reference for studying similar materials and can be used in physical simulation experiments for the prevention and control of coal and gas outbursts.

The Effect of Low Temperature and Strain Rate on the Mechanical Behavior of Precipitation-Strengthened HSLA Steels Alloyed with Ti and Nb

The Effect of Low Temperature and Strain Rate on the Mechanical Behavior of Precipitation-Strengthened HSLA Steels Alloyed with Ti and Nb

Deformation Behavior and Strengthening Mechanisms of a Typical Bimodal L12 Precipitates Strengthened Nickel‐Based Superalloy Over a Wide Range of Strain Rates and Temperatures

Nickel‐based superalloys with bimodal L12 precipitates have been widely used in extreme environments due to their excellent mechanical properties. However, limited studies have focused on the deformation behavior and mechanisms under combined high strain rates and high temperatures. In this study, uniaxial compression experiments were conducted on a typical bimodal L12 precipitates strengthened nickel superalloy over a wide range of temperatures (293–1273 K) and strain rates (1 × 10−3 s−1–5 × 103 s−1) to reveal the coupling effect of temperature and strain rate on the mechanical behavior. The results show that the mechanical behavior is highly sensitive to temperature and strain rate, with the alloy exhibiting remarkable high temperature strength, particularly under dynamic loading. The third‐type strain aging (3rd SA) effect is observed in this alloy, and its underlying mechanism is analyzed. Microstructural characterizations are conducted at various conditions, providing multiscale insight into the intricate relationship between microstructure and property. A transition in dominant deformation mechanisms is observed, shifting from anti‐phase boundary dislocation pair shearing to stacking fault as temperature increases. Additionally, a comprehensive diagram is provided to elucidate the deformation mechanisms of the alloy under a wide range of strain rates and temperatures.

Analysis of the Mechanical Stability of Power Transformer Windings Considering the Influence of Temperature Field

The power transformer is a critical primary device in the power grid, and the verification of its winding mechanical stability is of paramount importance in ensuring the safe and stable operation of the power grid. In the conventional numerical calculation methods for verifying the mechanical stability of power transformer windings, the influence of temperature variations at the winding hot spots on winding mechanical stability has not been taken into account. In reality, factors such as the transformer’s operating load rate, ambient temperature, and the duration of short-circuit fault currents passing through will affect the mechanical stability margin of the transformer windings. Under conditions such as winding aging, deformation, or other reasons, the transformer windings may become unstable due to material parameter degradation, leading to insufficient mechanical stability margin. This paper analyzes the mechanical stability of power transformer windings considering the impact of the temperature field. Initially, a numerical model for calculating short-circuit currents in transformers was established to compute the short-circuit current under three-phase short-circuit-to-ground conditions as an excitation. Subsequently, a 3D electromagnetic force finite element calculation model was developed to determine the electromagnetic forces experienced under this condition. The results of the calculated electromagnetic forces were then used in a numerical calculation method to assess the mechanical stability of the windings. Furthermore, a 3D transformer electromagnetic–thermal flow finite element model was created to calculate the steady-state temperature rise under various operating conditions of the transformer. This model is validated through transformer temperature rise tests, and transient temperature rises under different operating conditions are calculated. The obtained data are fitted using the nonlinear least squares method to derive a fitting function for the winding hot spot temperature concerning load rate, ambient temperature, and short-circuit time. Taking into consideration the influence of temperature on the yield strength and modulus of elasticity of transformer winding materials, the variation in mechanical stability margin of transformer windings due to temperature effects is analyzed. Additionally, the operating domain for preventing the transformer from becoming unstable under three-phase short-circuit impacts is calculated for different degrees of material parameter degradation. This method provides an effective reference for transformer design and operation, demonstrating clear practical value.

Effects of Different Temperatures on the Physiological Characteristics of Sweet Potato (Ipomoea batatas L. Lam) Storage Roots and Growth of Seedlings During the Sprouting and Seedling Period

Seedling cultivation is the foremost part of sweet potato (Ipomoea batatas L. Lam) production. It is of great significance to reveal the effects of different temperatures on the nutrients of sweet potato storage roots and their relationship with the sprouting quality and to explore the appropriate temperature management for seedlings. In this study, we simulated the temperature differences during the sprouting and seedling period in the summer growing area of sweet potato in the Yangtze River Basin and set three constant temperatures (17 °C, 22 °C and 27 °C) and corresponding three-day/night variable temperatures (21/13 °C, 26/18 °C and 31/23 °C). Thus, we investigated the nutrients, amylase activity, endogenous hormones, and sprouting characteristics of storage roots during the sprouting and seedling period of three sweet potato cultivars with different starch contents. The results showed that with the increase in temperature, the starch and soluble protein (SP) contents in sweet potato storage roots decreased, and the total soluble sugar (TSS), reducing sugar (RS), and sucrose contents increased during the sprouting and seedling period. The amylase activity enhanced; the hormone (IAA) content increased, and the abscisic acid (ABA) content decreased, which, in turn, led to an earlier time of sprouting time (ST), emergence stage (ES), and full stand of seedling stage (FSS). Comparing at the same average temperature, the physiological metabolism and sprouting time and quality of sweet potato were better at variable temperatures than at constant temperatures, in which 31/23 °C was more conducive to the advancement of the ST of sweet potato. At the same time, it was more conducive to the improvement of the seedling cutting amount (SCA), seedling weight (SDW), and seedling number (SDN). The sprouting time and quality of different sweet potato cultivars differed, and cultivars with higher starch content were superior to those with lower starch content. The sucrose and starch contents at different sprouting stages of storage roots can be used as important indicators of the quality of sweet potato seedlings.

Effects of Water Temperature, Light Intensities and Photoperiod on the Survival and Growth of Juvenile Schizothorax irregularis and Diptychus maculates

An experimental ecological method was used to study the effects of water temperature, photoperiod, and light intensity on the survival, feeding, and growth of juvenile Schizothorax irregularis and Diptychus maculates. The Box–Benhnken experiment was designed to predict the optimal environmental conditions for juvenile growth. With the maximum specific growth rate at 15 °C and a photoperiod of LD16:8, the results demonstrated that the juvenile S. irregularis had a survival rate of over 85% in water temperatures ranging from 5 to 25 °C. A daily light duration of 15.86 h and a light intensity of 1166.28 lx, with the water temperature maintained at 10.45 °C, allowed the juvenile S. irregularis fish to attain the optimal circumstances for growth and survival. At water temperatures below 25 °C, the juvenile D. maculates exhibited maximum specific growth rates at 10 °C and LD16:8 light period. Additionally, as the light intensity reached 1000 lx, the juvenile fish grew better. Furthermore, the juvenile D. maculates fish achieved theoretically optimal survival and growth circumstances when the water temperature was maintained at 10.87 °C with a light period of 15.0.5 h per day and a light intensity of 1474.68x. The results showed that both fish species may be raised in captivity in highland regions, but precise control over water temperature is required.

Effects of temperature on marbled crayfish (Procambarus virginalis, Lyko 2017) invasion ecology

Effects of temperature on marbled crayfish (Procambarus virginalis, Lyko 2017) invasion ecology