Optimum Temperature Range Research Articles

Eelgrass (Zostera marina) Trait Variation Across Varying Temperature-Light Regimes

Seagrass trait variation, which results from both local genetic adaptation and phenotypic plasticity, has important effects on ecosystems. Physical drivers underlie these processes and are important determinants of trait variation. Despite this, few studies examine multivariate predictive relationships between sets of physical drivers and sets of seagrass traits. Here, we use redundancy analysis to define this relationship for eelgrass Zostera marina, using traits that represent bed structure, morphology, and physiology and physical drivers that emphasize light conditions and temperature variability on different time scales. We found a relationship between plant size (i.e., leaf length and width, rhizome width, number of leaves) and shoot density that dominated the trait variation. Specifically, as temperatures became warmer, more variable, and light was less limiting, plants became smaller (shorter, narrower, and fewer leaves, thinner rhizomes) but beds became denser. Plant biomass (leaf area index), which increased with decreasing temperature variability and bottom light, further refined this relationship. Overall, temperature variability (i.e., daily temperature range, heat accumulation, time in the optimal temperature range, and tidal and meteorological variability), as well as bottom light, were important predictors of eelgrass traits. We further identified three distinct temperature-light regimes across which traits differed; these included the cool low variability temperature regime with low light, the warm high variability temperature regime with high light, and the intermediate case between these endpoints. Our study identifies specific temperature and light drivers that define certain eelgrass traits and provides a multivariate statistical model that can be used to predict eelgrass trait values from known physical conditions.

Study on the Mechanism of Temperature Effect on SO2 Electrochemical Gas Sensor

Abstract Temperature can affect the measurement values of electrochemical gas sensors, increasing measurement errors. The influence mechanism of temperature on electrochemical gas sensors was studied based on Fick's first law and the limit diffusion current formula. Temperature affects the sensitive characteristics of sensor by changing the diffusion coefficient Dl1 of SO2 in air, the Henry's coefficient KH of SO2 dissolved in water and the water content of the electrolyte solution. When the temperature increases, the degree of influence of Henry's coefficient KH and the reduction of water content is greater than the degree of influence on the increase in diffusion coefficient, which decreases the sensor measurement value. The results of the temperature experiments show that the optimal temperature range for the sensor is -25 °C to 50 °C, and the average measurement error in this temperature range is less than 20%. When the temperature exceeds 50 ℃, it will cause a reduction in the evaporation of water in the electrolyte solution, leading to a rapid increase in the measurement error. The structure of the sensor can be improved by adding a water retention layer inside the sensor to supplement the electrolyte solution with water, so as to reduce the measurement error.

Immobilization and characterization of β-galactosidase from Aspergillus oryzae in polyvinyl alcohol hydrogels.

One of the main goals of contemporary biotechnology has been the development of novel immobilized enzyme formulations. In the present study, the industrially important β-galactosidase was trapped in a polyvinyl alcohol (PVA) gel to immobilize it. The optimization of immobilization method and characterization of the immobilized enzyme were studied. The results were compared with free enzymes. The results indicate that the optimal temperature range for the enzyme to be at following immobilization is between 40°C and 50°C. At pH 7, the optimal pH, the activity increased, the Vmax value increased from 1.936 to 2.495 Umg‒1, and the Km value decreased from 4.861 to 0.982mM.Depending on how stable the immobilized enzyme when stored, β-galactosidases immobilized on PVA gels showed 52.87% activity at the end of the seventh week and 58.86% activity at the end of the fifth week. Their initial activity subsided after three reuses. The final result was 66%. Therefore, one may argue that it increases the catalytic effect of the enzyme. As a result, it has been found that immobilized β-galactosidase has more potent enzymatic properties than free β-galactosidase, which may make it more advantageous for industrial processes. Further studies could delve deeper into the mechanistic aspects of the immobilization process in an effort to improve optimization and tailor the immobilized enzyme to specific industrial needs.

Assessments and Investigation of Process Parameter Impacts on Surface Roughness, Microstructure, Tensile Strength, and Porosity of 3Dprinted Polyetherether Ketone (PEEK) Materials:

Additive manufacturing (AM) is emerging as a competitive technology with promising applications across various sectors, including biomedical, automotive, construction, and dental implants. This study investigates the influence of key process parameters on the surface roughness, microstructure, tensile strength, and porosity of Polyether Ether Ketone (PEEK), a high-performance thermoplastic used in dental prosthetics. Traditionally, metals and ceramics have been the standard for dental restorations, but advancements in computer-aided design (CAD) and computer-aided manufacturing (CAM) have improved accuracy, particularly for implant-supported prostheses. However, conventional methods like CAD-milling face challenges such as material waste and tool wear. AM techniques, such as fused deposition modeling (FDM), offer a solution by constructing objects layer by layer, minimizing waste. This research explores the effects of nozzle temperature on the mechanical properties of 3D-printed PEEK, emphasizing its role in optimizing performance and minimizing issues like porosity. Key factors like surface roughness and microstructure are highlighted as critical to the biocompatibility and longevity of dental restorations. The study identifies the optimal nozzle temperature range for PEEK 380-440°C, noting that deviations from this range lead to compromised mechanical properties. Overall, the findings provide valuable insights into optimizing the AM process for PEEK in dental applications and suggest that further biological and chemical studies are necessary to fully realize the material's potential in replacing traditional dental restoration materials.

Achieving refined microstructures and improved mechanical properties in a cup-shaped Mg-Gd-Y-Zr alloy casting by novel near-liquidus squeeze cast process

We have recently proposed a novel process named low frequency electro-magnetic stirring assisted near-liquidus squeeze cast (NSC), which has been shown effective grain refinement effect in pure Mg and binary Mg-RE alloys. In this work, the NSC process was introduced for fabricating of a cup-shaped casting by Mg-Gd-Y-Zr alloy (VW103K). The cup-shaped VW103K alloy castings fabricated by NSC process show good surface quality and dimensional accuracy, as well as with fine microstructures and no megascopic pores and surface shrinkages. At the cross section of the cup-shaped castings, the grain size, phase compositions and hardness are nearly equally distributed. The NSC processed VW103K alloy show finer average grain size and higher yield strength than that of gravity cast, squeeze cast and rheo-squeeze cast counter parts. Pouring temperature is critical and may influence the microstructure and mechanical properties of NSC processed alloys. With the decrease of pouring temperature from ∼660 to ∼630 °C, the grain size is decreased initially and then coarsened slightly, while the distribution of eutectic phase gets worse continuously. An optimal pouring temperature range of ∼660 to ∼640 °C was obtained for fabricating of VW103K alloy. The mechanisms on formation of fine microstructures in NSC processed VW103K alloys is the combined effects influenced by applied pressure, pouring temperature and the shape of mold cavity.

Preparation and Formation Mechanism of β-SiC Coatings Using a SiCl4-CH4-H2-N2 System.

The mechanism of β-SiC preparation via chemical vapor deposition (CVD) of the SiCl4-CH4-H2-N2 system remains unclear. Consequently, the change of molar Gibbs free energy of the CVD β-SiC chemical reaction in the SiCl4-CH4-H2-N2 system has been studied by the Helsinki Software Corporation (HSC) Chemistry code for the first time. The role of nitrogen in the reaction was confirmed. Seven potential reaction pathways of CVD β-SiC were presented, and the thermodynamic equilibrium components of each reaction were calculated systematically. The most viable reaction pathway and corresponding optimal temperature range for CVD β-SiC were determined. In addition, a kinetic study of CVD β-SiC was conducted. The microscopic morphology and crystal structure of β-SiC coatings prepared on the graphite surface at different temperatures were charactered by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman, etc. Ultimately, through SEM, XRD, and Raman observation, uniform and dense β-SiC coatings with fine grains and high crystallinity were successfully obtained. Furthermore, large β-SiC-coated graphite trays with diameters of 230 and 465 mm were prepared by CVD using the SiCl4-CH4-H2-N2 system, and the average thickness of β-SiC was about 100.6 μm. This study provides a theoretical basis and technical recommendations for the fabrication of SiC-coated graphite trays used in metal-organic chemical vapor deposition (MOCVD) equipment.

Effects of Climate Change on Temperature Sensitivity of Vegetation Growth in Huang-Huai-Hai Plain: Spatial–Temporal Dynamics and Ecological Adaptability

This paper explores the optimal temperature change in normalized difference vegetation index (NDVI) growth in the Huang-Huai-Hai Plain under the background of climate change, aiming to better cope with the impact of global warming on vegetation growth. The temporal and spatial variation characteristics of the NDVI and temperature factors were analyzed by using the NDVI, average temperature (Tavg), maximum temperature (Tmax) and minimum temperature (Tmin) datasets from 1982 to 2020. Through the Buishand U test and sliding slope detection, 1998 was determined to be a year of abrupt climate change. Furthermore, SHAP important feature analysis, a generalized additive model, correlation analysis, and other methods were used to identify the trend in the optimum temperature of vegetation growth before and after climate change. The results showed that (1) from 1982 to 2020, Tavg, Tmax, Tmin, and the NDVI in Huang-Huai-Hai Plain showed a significant upward trend. At the same time, the spatial distribution of these indicators shows the distribution characteristics of high in the south and low in the north. (2) The NDVI was positively correlated with Tavg, Tmax, and Tmin, and the correlation with Tmin was most significant. (3) The most suitable Tavg, Tmax, and Tmin intervals for vegetation growth were 20~30 °C, 25~35 °C, and 16~25 °C, respectively. (4) The optimum temperature range of vegetation growth was expanded after climate change, and the change rates of the Tavg and Tmax lower limits reached 24% and 25%, respectively, under the best condition of vegetation growth. (5) After abrupt climate change, the temperature suitable for vegetation growth increased significantly in the northern part of the plain but decreased slightly in the southern part.

Impact of Temperature on Reaction Rate in Catalytic Reactions

Purpose: The aim of the study was to assess the impact of temperature on reaction rate in catalytic reactions. Methodology: This study adopted a desk methodology. A desk study research design is commonly known as secondary data collection. This is basically collecting data from existing resources preferably because of its low cost advantage as compared to a field research. Our current study looked into already published studies and reports as the data was easily accessed through online journals and libraries. Findings: The study indicated that as higher temperatures generally increase the rate at which reactions occur. This is due to the fact that elevated temperatures provide the reactant molecules with more kinetic energy, enabling them to collide more frequently and with greater force, which is necessary to overcome the activation energy barrier. In catalytic reactions, temperature not only accelerates the intrinsic rate of the reaction but can also affect the activity and selectivity of the catalyst. However, too high a temperature can lead to catalyst deactivation through processes such as sintering or coke formation, where the catalyst surface is altered or blocked. Thus, an optimal temperature range is crucial to balance enhanced reaction rates while maintaining catalyst integrity and performance. Implications to Theory, Practice and Policy: Arrhenius equation, transition state theory and collision theory may be used to anchor future studies on the impact of temperature on reaction rate in catalytic reactions. In practical applications, industries should implement advanced temperature control systems to maintain optimal reaction conditions during catalytic processes. Policymakers have a critical role in shaping the landscape of catalytic reactions by developing regulatory guidelines focused on temperature management.

Optimal control of Hydrocarbon Reducer (HC) injection based on Trust-Region-Reflective Algorithm (TRRA) and physical models for Diesel Oxidation Catalyst (DOC)

The aim of this paper is to control the DOC outlet gas temperature between 600 ± 15 °C by optimizing the hydrocarbon (HC) injection into the Diesel Oxidation Catalyst (DOC) for active regeneration of the downstream Diesel Particulate Filter (DPF). First, based on the physical model of the DOC thermal dynamics, the energy conservation equation for the gas phase temperature is simplified by using variable substitution, and the energy conservation equation for the solid phase temperature is simplified by considering only the heat generated by the HC injection. By solving the simplified model using the Trapezoidal Rule-Backward Differentiation Formula 2 (TR-BDF2) method and optimizing the model parameters in combination with the Gauss-Newton method, the computational efficiency and accuracy were significantly improved. Next, the DOC downstream temperature observer is designed by combining the solution characteristics of the DOC model with the unscented Kalman filter (UKF) algorithm to ensure that the catalyst operates within the optimal temperature range. Then, this paper verifies the accuracy of the model and observer through bench tests covering four steady-state operation conditions and World Harmonized Transient Cycle (WHTC) test cycle, and the results show that the model and observer exhibit high accuracy in both steady-state and transient operation conditions. Finally, the DOC temperature was successfully maintained between 600 ± 15 °C by optimizing the control of the HC injection rate, thus achieving the expected temperature control target. These research results provide theoretical and practical support for diesel engine emission control and DPF active regeneration.

The Effect of Cooling Rate on Solidification Characteristics and Grain Structure of Al-9Si Cast Alloy

A thermal analysis study is essential before the semisolid metal processing of a particular alloy. The surrounding environment, especially the cooling rate is also an important factor. This study investigated the influence of different cooling rates on the solidification characteristics and microstructure evolution of the Al-9Si cast alloy. Four cooling mediums were designed, and their cooling rates are 0.16 ℃/s, 1.0 ℃/s, 1.3 ℃/s, and 1.9 ℃/s, respectively. The results show that the primary dendrite size of the Al-9Si alloy was reduced from 162.61 μm to 86.86 μm as the cooling rate increased from 0.16 ℃/s to 1.9 ℃/s. Significant grain refinement was observed, however, the external cooling has a negligible impact on solid fraction. The optimal temperature range of the Al-9Si cast alloy for the semisolid metal processing at a solid fraction of 0.5 to 0.7 is between 554 ℃ and 563 ℃. With these thermal profiles provided, the relationship between the solid fraction and the solidification time could be expressed using the polynomial equation, which is also useful for point prediction in the subsequent semisolid metal processing.

Designing Artificial Laccase Catalysts by Introducing Substrate Oxidation Metals into Oxygen-Reducing Metal-Organic Frameworks: Cu-doped ZIF-67.

Laccase, a multi-copper oxidase, is limited by its optimal temperature range and isolation costs. To overcome these challenges, we synthesized copper-doped zeolitic imidazolate framework-67 (Cu-ZIF-67) with 16 mol% Cu as an artificial laccase catalyst. The introduced Cu site acts as the phenol oxidation site, and Co-based ZIF-67 is the four-electron oxygen reduction site. Laccase also employs this division of oxidation and reduction sites. Cu-doped ZIF-67 demonstrated significant catalytic activity, superior to natural laccase, especially at elevated temperatures, and maintained stability across multiple reaction cycles. These findings suggest that Cu-doped ZIF-67 is a robust, reusable alternative for industrial applications requiring high thermal stability and efficient catalysis.

Study on biological zero and effective accumulated temperature of embryonic development and gonadal development of cuttlefish Sepia pharaonis

ABSTRACT Research on the aquaculture of cephalopods has emerged in the last 30 years. Compared to other animals, limited information exists on the fundamental biology of cephalopods, particularly regarding their gonadal and embryonic development. Detailed investigation into their reproduction and development could provide a solid practical basis for understanding their methods of reproduction and reproductive patterns for enhancing artificial-seeding cultivation techniques. Therefore, this study utilised the second generation (F2) of cultured cuttlefish, Sepia pharaonis Ehrenberg, 1831, controlling the hatching temperature of fertilised eggs and recording data at various stages of gonadal development. We calculated the biological zero, the effective cumulative temperature, the temperature coefficient for embryonic development and the effective cumulative temperature for gonadal development. The results indicated that the biological zero and effective cumulative temperature for embryonic development of S. pharaonis were 7.46 and 434.87 °C·d, respectively, with the optimal temperature range for embryonic development being 24–27 °C. The effective cumulative temperature for gonadal development was 853.04 ± 57.51 °C·d. This study provides essential information on the biological zeros and effective cumulative temperatures for both embryonic and gonadal development of S. pharaonis, offering significant practical information and a theoretical basis for future large-scale artificial cultivation of this species.

Analytical Techniques for Detecting Rare Earth Elements in Geological Ores: Laser-Induced Breakdown Spectroscopy (LIBS), MFA-LIBS, Thermal LIBS, Laser Ablation Time-of-Flight Mass Spectrometry, Energy-Dispersive X-ray Spectroscopy, Energy-Dispersive X-ray Fluorescence Spectrometer, and Inductively Coupled Plasma Optical Emission Spectroscopy

Rare earth elements (REEs) hold significant industrial, scientific, and modern technological worth. This study focused on detecting and quantifying REEs in various geological ore samples. These samples were collected from different REE-bearing locations recommended by geological experts. The analysis was conducted using laser-induced breakdown spectroscopy (LIBS) and laser ablation time-of-flight mass spectrometry (LA-TOF-MS). In this work, LIBS methodology was employed using three different configurations: standard LIBS, LIBS with an applied magnetic field, and LIBS with both an applied magnetic field and target sample heating within an optimal temperature range. Elements from the REE group, specifically lanthanum (La), cerium (Ce), and neodymium (Nd), were identified and quantified. To detect, quantify, and validate the results from LIBS and LA-TOF-MS, we utilized an array of analytical techniques—Energy-Dispersive X-ray Spectroscopy (EDX), Energy-Dispersive X-ray Fluorescence Spectrometer (ED-XRF), and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Interestingly, the quantitative results for REEs (La, Ce, and Nd) in the ore samples obtained using the LIBS technique with various configurations were found to be in agreement with those from LA-TOF-MS, EDX, XRF, and ICP-OES. In addition, LIBS enables detailed microchemical imaging, allowing the map of the spatial distribution of elements within the mineral–ore matrix. The high-resolution microscale elemental mapping of REEs was accomplished using the emission lines Ce (II) at 446.0 nm, La (II) at 492.1 nm, and Nd (II) at 388.8 nm. By integrating multiple analytical techniques, our study enabled the construction of a complete elemental distribution map, providing new insights into the geochemical processes and mineral composition of rare earth ores, while advancing geochemistry and contributing valuable data for rare earth resource exploration.

Analysis of Chiller Machine Energy Efficiency in the Paint Shop Air Handling Unit (AHU) Process

Abstract The Energy Efficiency in Industrial, Commercial, and Public Sector (EINCOPS) program is the result of a collaboration between the Indonesian Ministry of Energy and Mineral Resources and Danida (Danish International Development Assistance), which began in 2008 to support Indonesian government policies in achieving development goals in the field of sustainable environmental management. Energy users have gradually adopted energy efficiency measures in the industrial, commercial, and public sectors, starting with a large class. This research aims to obtain the optimal temperature range for using a chiller machine so that it continues to run efficiently. The method used is to calculate the coefficient of performance and energy efficiency ratio of each chiller when it is used. The number of chillers can be affected by the temperature range of the air handling unit (AHU), which uses wind from the environment as the main source for processing, and the temperature range is linear with weather conditions. This research found that in the environmental temperature range of 26°–29° Celsius taken by AHU for distribution to production areas, chiller performance is still not optimal. In the previous operation, three chillers were used out of the four available units, so after knowing the results of the chiller load analysis in this temperature range were still below standard or not optimal, the number of chillers could be reduced from three units full time to only two units when the temperature environment was in the range of 26°–29° Celsius. The results of calculating the average Coefficient of Performance and Efficiency Energy Ratio using two chillers when the temperature range of 26°–29° Celsius is still included in the standard, namely by increasing 0.15, the pre-improvement value is 5,833, and the chiller efficiency load increases to 14 percent.

Study on Pseudomonas spp. isolated from pork and chicken meat

Pseudomonas spp. are heterotrophic, Gram-negative, aerobic bacteria widely distributed in the environment, acting as food spoilage agents and opportunistic pathogens in humans. In this study, we applied the ISO 13720:2010 for enumeration of presumptive Pseudomonas spp. in meat and meat products to investigate the contamination of Pseudomonas spp. in pork and chicken meat samples collected from markets in various districts of Ho Chi Minh City. The results indicated that 78% of pork samples and 72% of chicken samples were contaminated with Pseudomonas spp., with average densities of 4.9×106 CFU/g and 6.8×106 CFU/g, respectively. Almost isolated Pseudomonas strains could grow at neutral and alkaline pH, with an optimal temperature range of 10°C to 44°C, and tolerate to NaCl 5%. These findings provide critical information on the distribution and growth characteristics of Pseudomonas spp. in meat, therefore, being a premise to propose the research on density thresholds to ensure food quality.

EVALUATION OF TECHNOLOGICAL PLASTICITY OF HIGH BORON CORROSION-RESISTANT STEEL DURING HOT DEFORMATION OF PIPES USED FOR SPENT NUCLEAR FUEL STORAGE

Statement of the problem. The sustainable development of the global nuclear power industry in the future depends on how effectively the problems of radiation safety and nuclear proliferation are addressed. Such problems occur, among other things, at the final stage of the nuclear fuel cycle – spent fuel management. This task is currently on the agenda of both the international community and national governments of countries that develop or intend to develop nuclear energy [1−3]. Today, in connection with ensuring the safety of nuclear energy, boron-containing steels are widely used in the world practice as a material for biological protection and for the manufacture of special equipment parts. This is due to the fact that the B10 isotope in steels provides neutron capture [4]. Hexagonal pipes made of high-boron steel were needed to shield the support cover of the compacted spent fuel storage facility at nuclear power plants. Corrosion-resistant steels alloyed with boron are widely used in the nuclear power industry due to their special nuclear properties. During the operation of nuclear power plants, fuel assemblies that have served their useful life must be stored in special storage facilities using containers – hexagonal tubes made of 04Сr14Ti3B2V steel. To reduce costs during in the construction and operation of NPPs, part of the spent nuclear fuel management should be performed at Ukrainian enterprises. This will provide a significant import substitution effect. To manufacture hexagonal tubes from 04Сr14Ti3B2V steel according to the ingot-hot deformation-profiling-heat treatment scheme, it is necessary to develop the parameters of hot deformation and subsequent technological operations. The use of these pipes in compacted spent fuel storage facilities of NPPs will allow to increase the storage capacity by 2 times, which will give a significant national economic effect Material and methods of research. Material used for the study was steel 04Сr14Ti3B2V (CS-82), smelted using two variants (vacuum-induction – “VI” and vacuum-induction followed by vacuum-arc remelting – (“VD”). Steel grade 04Сr14Ti3B2V belongs to high-alloy, corrosion-resistant ferritic steels with a high boron content of up to 2 %. The method of differential thermal analysis was used to study the phase transformation temperatures in the steel. X-ray diffraction and micro-X-ray spectral analysis were used to assess the phase state. The steel samples were tested for weldability After cooling, the welded samples were subjected to X-ray transmission [5]. Hot twisting tests and mechanical tests at high temperatures were also performed. The macro- and microstructure of the metal was studied. Results. The macro- and microstructure of steel was evaluated depending on the smelting method. The phase composition of the steel was studied. The study of the plastic properties of steel ChS-82 by means of penetration and hot twisting tests showed that the temperature range of maximum plasticity is in a wide range (from 1 025 to 1 150 0C) with a rather low resistance to deformation. During hot deformation in the temperature range of 1 175 0C and above, metal fracture was observed along the grain boundaries at the melting points of the Cr−Fe−B boride phase. The optimal temperature range for hot deformation of steel ChS-82 is 1 000−1 050 ⁰С. Scientific novelty. For corrosion-resistant high boron steel used for spent nuclear fuel storage, the temperature range of hot deformation was selected and the structural and phase composition was estimated, which will allow deforming the metal on the piercing mill and manufacturing pipes.

Feasibility of upcycling red mud for low-CO2 cement via calcination: A comparative study with FA and GGBFS based in China

This study examines the feasibility of developing low-CO2 cement using calcined red mud (RM) and explores positive scenarios that simultaneously attain technical, environmental, and economic benefits in reference to conventional fly ash (FA) and ground granulated blast furnace slag (GGBFS) cements. Based on the variables of RM's content and calcination temperature, we investigated the fresh properties (paste rheology and mortar flowability), strength development, microstructure, embodied CO2 emissions, and cost of the RM-blended cement. The results show that there was an optimal range of RM's calcination temperature (400–600 °C) that improved the cement paste viscosity while attaining a higher strength than that of FA cement. Considering the cradle-to-gate CO2 emissions and cost of cement production, the optimal cement composition is comprised of up to 30% RM calcined at 600 °C, where the cement cost is lowered by 19.3% compared to the FA reference having a comparable CO2 footprint. According to the geographical analysis, the calcined RM shows minimal advantages over GGBFS but could substitute FA as a cleaner, cheaper, and more reactive supplementary cementitious material in regions where electricity grid is dominated by clean energy. Therefore, RM offers a plausible solution to future low-CO2 cement in light of the increasing shortage of FA led by the declining use of coal-powered electricity.

Thermal management analysis with different PCMs in Sodium-Ion batteries

The advent of modern technology has led to a significant increase in the utilisation of rechargeable secondary batteries. Despite the sustainability of lithium-ion (Li-ion) batteries, the limited availability of lithium has driven research into alternative energy storage technologies. Sodium-ion (Na-ion) batteries, as a potential alternative to Li-ion batteries, have emerged as a highly promising contender. However, for these batteries to become industrially viable, certain properties such as energy and power density need to be enhanced. To address this issue, batteries have been a focus of research, and battery thermal management systems have been developed. These systems aim to evaluate battery performance, which is strongly influenced by temperature. Effective thermal management ensures that the battery operates within the optimal temperature range. This study models a pouch-type battery and evaluates the effects of phase changing materials (PCM) on battery temperature control. Comparative analysis is conducted using different PCMs to understand their impact. The study analyses the battery's response to specific temperature ranges and assesses how different PCMs affect battery cooling performance. The results provide critical insights for ensuring efficient battery operation. Furthermore, this research supports the broader adoption of Na-ion batteries in industrial applications and contributes to the development of sustainable energy storage systems.

Optimization for the temperature range of radiator for preventing draught risk of cold window

High surface temperature of radiator can provide thermal plume with enough momentum intensity and thus counteracts the downdraft caused by window. Meanwhile, it is necessary to avoid causing indoor temperature to exceed upper limit of thermal comfort zone. In this paper, influence of heat transfer coefficients of window and exterior wall, outdoor temperature, and average surface temperature of radiator on operative temperature (Top) and temperature difference between indoor air and window (Td) was investigated. Based on response surface method, single factor and interaction effects for the four influencing factors on Top and Td were analyzed. A framework optimizing average surface temperature of radiator for preventing draught risk of window was established. When the heat transfer coefficient of window was around 1.4 W/m2·°C and satisfied related energy-conservation standard, cold draught could be eliminated without causing indoor environment overheating. Based on the optimized temperature range, the supply water temperature was controlled, and seasonal performance using the variable temperature strategy was investigated based on TRNSYS simulation. With the variable water temperature control strategy, the output hourly indoor air temperature was within the comfortable range. In the whole heating season, hours that did not meet cold draught requirement occupied 77.22 %, as the heat transfer coefficients of window dis-satisfied the energy-saving design standard. As meeting the design standard, the proportion decreased to 12.97 %. Utilizing the optimized temperature interval can prevent discomfort caused by cold draught to the greatest extent. This study is conducive to improving thermal environment with the convective–heating system and may lead to the reduction of energy consumption for heating.

Sintering trials and microstructural changes mechanism of analogues of americium oxides for radioisotope power systems

Radioisotope thermoelectric generators (RTGs) are deal energy supply devices for deep space and deep-sea exploration, and it is also the energy core of the operation of the working equipment. Except for 238Pu (Plutonium), 241Am (Americium) was also used as a nuclide in the radioactive energy system for future space exploration missions. In this work, neodymium oxide (Nd2O3) was used as analogues for Am2O3. Cold-press-and-sinter methods was used. Different particle parameters (morphology, size, and crystal structure) and synthesized parameters of Nd2O3 were investigated. The synthesized powders contained lath-shaped particles, and batches with different particle sizes and microscopic topography were made and sintered. The results show that the optimal precipitation temperature of Nd2O3 is 25 °C. The optimal thermal decomposition temperature range is 900 °C to 1100 °C, and the optimal thermal decomposition heating rate is 10 °C min−1. The samples of Nd2O3 pellets without cracking is obtained with relative density of 85%–90 %. The Vickers hardness of Nd2O3 pellets was also studied. This paper provides an important scientific guiding significance for the cold-press-and-sinter of radioisotope 241Am batteries in the future.