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Quantifying the temperature sensitivity of methane (CH4) production is crucial for predicting how wetland ecosystems will respond to climate warming. Typically, the temperature sensitivity (often quantified as a Q10 value) is derived from laboratory incubation studies and then used in biogeochemical models. However, studies report wide variation in incubation-inferred Q10 values, with a large portion of this variation remaining unexplained. Here we applied observations in a thawing permafrost peatland (Stordalen Mire) and a well-tested process-rich model (ecosys) to interpret incubation observations and investigate controls on inferred CH4 production temperature sensitivity. We developed a field-storage-incubation modeling approach to mimic the full incubation sequence, including field sampling at a particular time in the growing season, refrigerated storage, and laboratory incubation, followed by model evaluation. We found that CH4 production rates during incubation are regulated by substrate availability and active microbial biomass of key microbial functional groups, which are affected by soil storage duration and temperature. Seasonal variation in substrate availability and active microbial biomass of key microbial functional groups led to strong time-of-sampling impacts on CH4 production. CH4 production is higher with less perturbation post-sampling, i.e. shorter storage duration and lower storage temperature. We found a wide range of inferred Q10 values (1.2-3.5), which we attribute to incubation temperatures, incubation duration, storage duration, and sampling time. We also show that Q10 values of CH4 production are controlled by interacting biological, biochemical, and physical processes, which cause the inferred Q10 values to differ substantially from those of the component processes. Terrestrial ecosystem models that use a constant Q10 value to represent temperature responses may therefore predict biased soil carbon cycling under future climate scenarios.

The relative fluorescence intensity from different multi-photon processes is affected by the excitation light source fluctuation, which reduces the anti-interference and sensitivity of thermometers based on fluorescence intensity ratio (FIR) in upconversion (UC) luminescence. Ca 1-x Mg x WO 4 : Yb3+, Er3+ phosphors with scheelite structure were synthesized to investigate their anti-interference and higher temperature sensitivity. With x increasing from 0 to 1, the Bragg angle shifted toward higher angle, indicating that the larger disorders were introduced into the phosphors. The emissions assigned to Er3+ were enhanced with Mg2+ concentration increasing, attributed to oxygen vacancies according to the results of electron paramagnetic resonance. The photon numbers of upconversion luminescence assigned to 2H 11/2 → 4I 15/2 , 4S 3/2 → 4I 15/2 and 4F 9/2 → 4I 15/2 transitions of Er3+ were three- and two-photon processes, respectively. The ratio between the cube of 4S 3/2 and the square of 2H 11/2 emissions revealed higher temperature sensing performance and anti-interference on the excitation source power than the that between 4S 3/2 and 2H 11/2. The maximum relative sensitivity was 0.66 % K−1 at 300 K based on the common optical ratiometric thermometry. The maximum relative sensitivity based on the emissions assigned to different multi-photon processes was 7.2 % K−1 at 573 K. The dopants of Mg2+ composited of oxygen vacancies in CaWO 4 crystals improved the luminous intensity and temperature sensing performance. This suggested the potential application of optical ratiometric thermometers based on different multi-photons of UC luminescence in temperature sensing field. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) and phosphorus (P) depositions have been shown to alter nutrient availability in terrestrial ecosystems and thus largely influence soil carbon cycling processes. However, the general pattern of nutrient‐induced changes in the temperature response of soil carbon decomposition is unknown. Yet, understanding this pattern is crucial in terms of its effect on soil carbon–climate feedback. Here, we report that N and P additions significantly increase the temperature sensitivity of soil organic carbon decomposition (Q10) by sampling soils from 36 sites across China's forests. We found that N, P, and their co‐addition (NP) significantly increased the Q10 by 11.3%, 11.5%, and 23.9%, respectively. The enhancement effect of nutrient addition on Q10 was more evident in soils from warm regions than in those from cold regions. Moreover, we found that nutrient‐induced changes in substrate availability and initial substrate and nutrient availability mainly regulated nutrient addition effects. Our findings highlight that N and P deposition enhances the temperature response of soil carbon decomposition, suggesting that N and P deposition should be incorporated into Earth system models to improve the projections of soil carbon feedback to climate change. [ABSTRACT FROM AUTHOR]

Ecosystem respiration (Reco) arises from interacting autotrophic and heterotrophic processes constrained by distinct drivers. Here, we evaluated up‐scaling of observed components of Reco in a mature eucalypt forest in southeast Australia and assessed whether a land surface model adequately represented all the fluxes and their seasonal temperature responses. We measured respiration from soil (Rsoil), heterotrophic soil microbes (Rh), roots (Rroot), and stems (Rstem) in 2018–2019. Reco and its components were simulated using the CABLE–POP (Community Atmosphere‐Biosphere Land Exchange–Population Orders Physiology) land surface model, constrained by eddy covariance and chamber measurements and enabled with a newly implemented Dual Arrhenius and Michaelis‐Menten (DAMM) module for soil organic matter decomposition. Eddy‐covariance based Reco (Reco.eddy, 1,439 g C m−2 y−1) was slightly higher than the sum of the respiration components (Reco.sum, 1,295 g C m−2 y−1) and simulated Reco (1,297 g C m−2 y−1). The largest mean contribution to Reco was from Rsoil (64%) across seasons. The measured contributions of Rh (49%), Rroot (15%), and Rstem (22%) to Reco.sum were very close to model outputs of 46%, 11%, and 22%, respectively. The modeled Rh was highly correlated with measured Rh (R2 = 0.66, RMSE = 0.61), empirically validating the DAMM module. The apparent temperature sensitivities (Q10) of Reco were 2.22 for Reco.sum, 2.15 for Reco.eddy, and 1.57 for CABLE‐POP. This research demonstrated that bottom‐up respiration component measurements can be successfully scaled to eddy covariance‐based Reco and help to better constrain the magnitude of individual respiration components as well as their temperature sensitivities in land surface models. Plain Language Summary: Ecosystem respiration (Reco) represents losses of carbon from the land to the atmosphere and consists of aboveground plant respiration and belowground root and microbial respiration. Because respiration processes increase exponentially with temperature, understanding their contributions to Reco is critical to predicting carbon cycle responses to warming. We used field observations to test and improve the modeling of respiration components of an evergreen eucalypt forest in Australia. Field measurements indicated that the model adequately captured the quantitative contributions of respiration components to Reco. In particular, the improved microbial version of the model was in good agreement with measurements. However, improvements are needed for modeling and measuring the autotrophic components from roots, stems, and forest canopy. This study highlights that scaling up individual respiratory sources and their temperature responses provides insights to understanding ecosystem scale carbon cycle‐climate feedbacks. Key Points: Concurrent scaled chamber measurements matched flux tower observations to within 10%Implementing a substrate function into a land surface model improved representation of heterotrophic respirationDiscrepancies between observations and simulations were largest for temperature sensitivity of canopy and root respiration [ABSTRACT FROM AUTHOR]

This study aimed to determine the optimal water, temperature, and density conditions, alongside antifungal treatments, for pea (Pisum sativum L.) germination in a laboratory setting, with implications for research, breeding, and microgreen production. Germination and early seedling growth were assessed across various temperatures (5 °C to 40 °C), water levels (0–14 mL per Petri dish), seed densities (5, 7, 9, and 11 seeds per Petri dish), and antifungal treatments (Hypo and Bordeaux mixture). The results indicated that optimal germination occurred between 15 °C and 25 °C, with peak performance at 25 °C. Water levels between 7 and 11 mL per 9 cm diameter Petri dish supported robust root and shoot development, while minimal water levels initiated germination but did not sustain growth. Five seeds per Petri dish was optimal for healthy development, whereas higher densities led to increased competition and variable outcomes. Antifungal treatments showed slight improvements in germination and growth, though differences were not statistically significant compared to controls. The study's novelty lies in its holistic approach to evaluating multiple factors affecting pea germination, offering practical guidelines for enhancing germination rates and seedling vigor. These findings support efficient and resilient crop production systems adaptable to varying environmental conditions, contributing to sustainable agriculture and food security. Future research should explore these factors in field settings and across different pea cultivars to validate and refine the recommendations. [ABSTRACT FROM AUTHOR]

The temperature sensitivity (Q10) of soil organic C (SOC) decomposition is an important parameter to predict C dynamics under climate change. Given that SOC is mainly protected by aggregates and minerals, differentiating the Q10 of the two C fractions helps to explain bulk soil C dynamics. In the present study, we collected agricultural soils from adjacent paddy and upland areas in mid‐temperate (Mollisols) and subtropic (Ultisols) regions of China. We employed density fractionation to separate aggregate‐protected and free mineral‐associated C fractions of soil samples and determined the Q10 of SOC and the two C fractions at 15 and 25°C incubated conditions. Results showed that the Q10 of SOC for Mollisols were lower than that for Ultisols, with an exception of aggregates in upland soils. Aggregate‐protected C had lower Q10 than free mineral‐associated C, except in the upland Mollisols. The Q10 of SOC was negatively correlated with the proportion of C protected in aggregates, whereas it was positively correlated with the proportions of mass or C of free minerals. Given that the mass and C proportion of aggregates in bulk soils of Mollisols were 271% and 80% higher than of Ultisols, respectively, the SOC of Mollisols exhibited lower Q10 than Ultisols. Therefore, stronger soil aggregation and higher proportion of aggregate‐protected C contributed to the lower temperature sensitivity of SOC in Mollisols. Consequently, agricultural practices aimed at promoting soil aggregation will alleviate SOC loss under future global warming scenarios. [ABSTRACT FROM AUTHOR]

Tropical forest photosynthesis can decline at high temperatures due to (1) biochemical responses to increasing temperature and (2) stomatal responses to increasing vapor pressure deficit (VPD), which is associated with increasing temperature. It is challenging to disentangle the influence of these two mechanisms on photosynthesis in observations, because temperature and VPD are tightly correlated in tropical forests. Nonetheless, quantifying the relative strength of these two mechanisms is essential for understanding how tropical gross primary production (GPP) will respond to climate change, because increasing atmospheric CO2 concentration may partially offset VPD‐driven stomatal responses, but is not expected to mitigate the effects of temperature‐driven biochemical responses. We used two terrestrial biosphere models to quantify how physiological process assumptions (photosynthetic temperature acclimation and plant hydraulic stress) and functional traits (e.g., maximum xylem conductivity) influence the relative strength of modeled temperature versus VPD effects on light‐saturated GPP at an Amazonian forest site, a seasonally dry tropical forest site, and an experimental tropical forest mesocosm. By simulating idealized climate change scenarios, we quantified the divergence in GPP predictions under model configurations with stronger VPD effects compared with stronger direct temperature effects. Assumptions consistent with stronger direct temperature effects resulted in larger GPP declines under warming, while assumptions consistent with stronger VPD effects resulted in more resilient GPP under warming. Our findings underscore the importance of quantifying the role of direct temperature and indirect VPD effects for projecting the resilience of tropical forests in the future, and demonstrate that the relative strength of temperature versus VPD effects in models is highly sensitive to plant functional parameters and structural assumptions about photosynthetic temperature acclimation and plant hydraulics. [ABSTRACT FROM AUTHOR]

In this study, we studied the shear thickening performance of a novel silicon nitride and silica-mixed nanoparticles suspension. Silicon-nitride/silica-shear thickening fluids (Si3N4/SiO2-STFs) with different mass fraction ratios were prepared using polyethylene glycol as a dispersion medium. For the Si3N4/SiO2-STFs, the results showed that the viscosity increased from 168.35 (0.0 wt% Si3N4) to 1387.73 Pa s (7.5 wt% Si3N4), and a concomitant decrease in the critical shear rate from 10.0 to 3.55 s–1, while thickening period decreased from 60.92 to 16.03 s–1. Dynamic rheological analysis showed that compared with SiO2-based STF (SiO2-STF), the peak values of storage and loss modulus of 7.5%Si3N4/20%SiO2-STF (7.5 wt% Si3N4 and 20 wt% SiO2) increased nearly six times and three times, respectively. The results also showed that, compared with SiO2-STF, the thickening ratio of 7.5%Si3N4/20%SiO2-STF increases by 174% at 45°C and slows down the effect of temperature increase on the thickening period. This work provides a novel method for high-performance STF. [ABSTRACT FROM AUTHOR]

Rod-type metal corrosion probes based on electromechanical impedance (EMI) technique can quantitatively assess the amount of corrosion, which have a promising application in pipeline corrosion monitoring and have received much more attention. In the field of structural health monitoring, the EMI technique based on series and parallel connections has been widely studied and is very promising, but it is yet to be used in the probe design. In this work, a kind of novel metal corrosion probe with two piezoelectric elements in series and parallel connections was proposed, and its performance was investigated comprehensively by combining theoretical analysis with experiment research. Theoretical models of the proposed probe in the longitudinal vibration mode for both series and parallel connections were established, and verified by the experimental results. Influences of the thicknesses of piezoelectric layer and ceramic layer on the probe performance were analyzed. Artificial quantitative corrosion tests and accelerated corrosion tests were designed to evaluate the quantitative corrosion monitoring capacity. Temperature sensitivity tests were conducted to study the temperature dependence. The wireless impedance measurement was performed to confirm the online monitoring ability. Comparisons for the probe performance between the series and parallel connections were also presented. This work provided a comprehensive understanding for this kind of novel probe, which is beneficial to develop low-cost, high-precision, high-stability pipeline corrosion real-time monitoring technology. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office 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.)

Purpose: A prerequisite for the successful application of phytoliths in paleoenvironmental reconstruction is the correct interpretation of their environmental significance. In this context, key questions include: What magnitude of temperature/precipitation change is required to effect significant changes in surface soil phytolith percentages? When temperature/precipitation increases by a certain amount, what is the corresponding response of the percentages and assemblages of surface soil phytoliths? Additional detailed research is required to answer these questions. Materials and methods: We analyzed the phytoliths in 90 surface soil samples collected along the isohyets corresponding to the mean annual precipitation (MAP) of 400 mm (with the mean annual temperature (MAT) range of 3.24℃) and 600 mm (with the MAT range of 8.29℃) in Northeast China. Our objective was to determine the response of phytoliths to different temperature gradients. Soil phytoliths were extracted and identified using heavy liquid separation and microscope observations. Results: The DA of the phytolith percentages enabled the separation of samples collected along the two isohyets, with a total accuracy of 94.44%. MAT was the principal factor affecting the spatial distribution of phytoliths, with an explanation rate of 46.40%. In the surface soil samples collected along the two isohyets, the percentages of ELONGATE, ACUTE BULBOSUS, and PTERIDOPHYTE-TYPE morphotypes, were significantly negatively correlated with MAT, while the percentages of SQUARE were significantly positively correlated with MAT. However, the relationship between PAPILLATE percentages and MAT varied, showing both positive and negative correlations. A temperature gradient of ~ 3℃ was insufficient to significantly affect the percentages of SADDLE, BULLIFORM FLABELLATE, and BILOBATE. The phytolith index (C/W) can be effectively used to reconstruct the palaeoclimate in Northeast China. An MAP change of 200 mm resulted in significant changes in the percentages of ELONGATE, SADDLE, BULLIFORM FLABELLATE, and TRACHEARY (with the respective rates of 39.57%, 780.77%, 179.00% and 81.25%). However, the percentages of ACUTE BULBOSUS, SQUARE, RONDEL, BILOBATE, CRENATE, PTERIDOPHYTE-TYPE, SILICIFIED STOMATA, and PAPILLATE did not change significantly. Conclusions: Our results contribute to an improved understanding of the response of various phytolith morphotypes to temperature, and they provide a modern process basis for future phytolith-based paleoclimatic reconstruction in this region. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry 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.)

An evaluation of low damage guar gum fracturing fluid system based on deep coalbed methane reservoir stimulation was carried out, its on-site application research was conducted. The results indicate that the gel breaking time decreases with increasing temperature. Low damage guar gum fracturing fluid has a significant breaking expression in a short period of time at temperature above 40 ℃, which is not obvious at 20 ℃ and 30 ℃. The permeability of coal core is sensitive to temperature, which leads to an increase in core damage rate, but the amplitude of change is relatively small. For low damage guar gum fracturing fluid, the increase rate of temperature sensitivity of coal core to damage rate is much lower than the decrease rate of guar gum fracturing fluid damage rate to coal core with the increasing temperature from 20 ℃ to 40 ℃. Overall, the damage rate of guar gum fracturing fluid to coal core significantly decreases with the increase of temperature. For active water, the damage rate of active water to coal core increases when the temperature rises from 20 ℃ to 40 ℃. The backflow fluid viscosity reaches 5 mPa·s of guar gum fracturing in 2 hours at temperatures above 40 ℃, meeting the needs of on-site construction. By comparing the fracturing results of low damage guar gum fracturing and active water in the same well and horizontal well at the same layer, low damage guar gum fracturing fluid can achieve a fracturing process with less injection volume, larger sand volume, higher sand ratio, and smoother pressure.

The Tibetan Plateau holds the world's largest alpine permafrost and is undergoing an acceleration of warming. Phenological shifts over alpine permafrost in a warmer world have been little studied and are greatly underrepresented in current syntheses.Here, we conducted seasonal and gradient temperature‐controlled experiments in a permafrost‐affected meadow to evaluate how warming drives shifts in spring and autumn phenology, and associated growing‐season length at both community and species levels.We found that there is no sign of slowdown in spring advance with warming under a higher year‐around warming treatment, aligning with a future medium warming scenario. Although spring advance led to an advance in autumn senescence according to spring‐only warming experiments, the advance could not offset the delay due to concurrent warming. As a result, year‐around warming significantly delayed autumn senescence, although there was a deceleration in delay with warming under high temperature treatment than under the low one.This finding can be attributed to the possibility that winter warming is insufficient to reduce chilling accumulation, which would not delay spring phenology and then lead to a non‐slowdown in spring phenological advancement. Taken together, there is no slowdown in an extension of growing season length with warming under a higher year‐around warming treatment, with an increase of length by 9 and 21 days at the end of this century under a CO2 stabilization and medium warming scenarios, respectively.Synthesis. Our results suggest that a continued growing season extension at least under the medium warming scenario would help permafrost‐affected meadow ecosystems to mitigate permafrost carbon release on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composition and microbial respiration from decomposing wood of angiosperms and gymnosperms in a subtropical forest. Nutrient additions significantly increased wood microbial respiration via fungal composition, but effects varied with nutrient types and taxonomic groups. Specifically, phosphorus addition significantly increased wood microbial respiration (65%) through decreased acid phosphatase activity and increased abundance of fast‐decaying fungi (e.g., white rot), while nitrogen addition marginally increased it (30%). Phosphorus addition caused a greater increase in microbial respiration in gymnosperms than in angiosperms (83.3% vs. 46.9%), which was associated with an increase in Basidiomycota:Ascomycota operational taxonomic unit abundance in gymnosperms but a decrease in angiosperms. The temperature dependencies of microbial respiration were remarkably constant across nutrient levels, consistent with metabolic scaling theory hypotheses. This is because there was no significant interaction between temperature and wood phosphorus availability or fungal composition, or the interaction among the three factors. Our results highlight the key role of tree identity in regulating nutrient response of wood microbial respiration through controlling fungal composition. Given that the range of angiosperm species may expand under climate warming and forest management, our data suggest that expansion will decrease nutrient effects on forest carbon cycling in forests previously dominated by gymnosperm species. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) residues (root and straw) are unique substrates for microbes in paddy soils. Microbial respiration (RH) of paddy soils is likely to be affected by substrate quality. However, no relevant study on the effects of changed rice residue chemistry by climate change on the temperature sensitivity (Q10) of the RH of soils amended with the residues is available. To fill this knowledge gap, we conducted an incubation experiment (at 15, 25, and 35 °C) with rice residues of which lignin, nonstructural carbohydrate (NSC), and carbon-to-nitrogen ratio (C/N) were modified by growing the rice plants under different CO2 and air temperature (Tair). Co-elevated CO2 and Tair decreased lignin and C/N but increased the NSC contents of the residues, leading to the greater RH in the soils amended with rice residues produced under co-elevated CO2 and Tair compared to other CO2 or Tair treatments. However, the Q10 values of the RH of soils amended with rice residues produced under different CO2 and Tair were marginally changed, probably due to other confounding factors such as soil enzyme activity and nutrient availability. Despite that, there was a negative relationship between NSC and Q10 for soils amended with straw of which C/N is lower than root, agreeing with the kinetic theory on "substrate quality–Q10 relationship". Our result suggests that residue chemistry may not affect the Q10 of soils with root residue, but for straw-amended soils, less-recalcitrant NSC rather than more-recalcitrant lignin of straw may be critical in determining the Q10 of the soils. [ABSTRACT FROM AUTHOR]

The magnitude of terrestrial carbon (C)‐climate feedback largely depends on the temperature sensitivity of soil organic matter (SOM) decomposition (Q10). However, our understanding of determinants of Q10 for SOM fractions such as particulate and mineral‐associated organic matter (POM and MAOM, respectively) is still inadequate. Particularly, it remains unclear whether microbial effects on Q10 are fraction‐dependent, which induces large uncertainties in projecting soil C dynamics. Here, we conducted large‐scale topsoil sampling on the Tibetan Plateau, in combination with SOM fractionation and 300‐day laboratory incubation to assess SOM fraction‐dependent linkages between Q10 and microbial properties. We found that compared with MAOM, POM had larger Q10 and greater microbial diversity, and also structured distinct microbial communities as well as their co‐occurrence patterns. Furthermore, associations of Q10 with microbial properties differed between the two SOM fractions. Bacterial community composition and relative abundance of bacterial keystone taxa affected Q10 for POM and MAOM respectively, while bacterial alpha diversity showed opposite relationships with Q10 for POM and MAOM. These findings highlight the necessity of incorporating SOM fraction‐dependent microbial properties and their linkages with Q10 into Earth system models to accurately predict terrestrial C‐climate feedback. [ABSTRACT FROM AUTHOR]

Summary: The temperature sensitivity (e.g. Q10) of night‐time leaf respiratory CO2 efflux (RCO2) is a fundamental aspect of leaf physiology. The Q10 typically exhibits a dependence on measurement temperature, and it is speculated that this is due to temperature‐dependent shifts in the relative control of leaf RCO2. Two decades ago, a review hypothesized that this mechanistically caused change in values of Q10 is predictable across plant taxa and biomes. Here, we discuss the most appropriate measuring protocol among existing data and for future data collection, to form the foundation of a future mechanistic understanding of Q10 of leaf RCO2 at different temperature ranges. We do this primarily via a review of existing literature on Q10 of night‐time RCO2 and only supplement this to a lesser degree with our own original data. Based on mechanistic considerations, we encourage that instantaneous Q10 of leaf RCO2 to represent night‐time should be measured: only at night‐time; only in response to short‐term narrow temperature variation (e.g. max. 10°C) to represent a given midpoint temperature at a time; in response to as many temperatures as possible within the chosen temperature range; and on still attached leaves. [ABSTRACT FROM AUTHOR]

Accurate modeling of photovoltaic (PV) modules/cells is crucial for evaluating the efficiency of solar PV systems. However, the lack of specific parameters of solar cells, which are not included in the manufacturer's datasheet, often results in flawed cell modeling. Quick and convenient parameter extraction techniques are required to overcome this challenge and create a robust solar PV cell model. These models are useful in optimization, simulation, and enhanced energy harvesting from PV-based renewable energy systems. This paper uses a recent optimizer called Rat Search Algorithm Particle Swarm Optimization (RSAPSO), for extracting the parameters of single diode and double diode models of PV cells. RSAPSO combines the exploration and exploitation advantages of both algorithms. The RSAPSO's parameter optimization results were compared against five other techniques, and the superiority of the suggested algorithm was confirmed through ranking tests, statistical error analyses, and temperature variation sensitivity analyses. [ABSTRACT FROM AUTHOR]

Multiphase phosphors have garnered increased attention for their notable photothermal sensing properties. The temperature sensitivity of multiphase composites is significantly influenced by heat treatment, which impacts the interfacial diffusion of emitting centers. This study delved into the structural and optical properties of ZnAl 2 O 4 :Eu3+-ZnTiO 3 :Mn4+ composites with varying annealing temperatures. Distinct photoluminescence spectra of Eu3+ were observed in ZnAl 2 O 4 matrix, accompanied by a robust emission band corresponding to the 2E g → 4A 2g transition of Mn4+ in cubic ZnTiO 3 crystals. Notably, a sharp emission band at 714 nm emerged as the measurement temperature decreased, which is attributed to Mn4+ in hexagonal ilmenite ZnTiO 3. The emission intensity of Mn4+ in mixed phosphors decreased with increasing annealing temperature. The temperature dependence of emission peaks was investigated in two temperature regions of 80–260 K and 300–390 K for the ZnAl 2 O 4 :Eu3+-ZnTiO 3 :Mn4+ mixed phosphors with varying annealing temperatures. A second heat treatment at different temperature significantly influenced the optical properties associated with Eu3+ and Mn4+. In low temperature region, the highest temperature relative sensitivity reached 2.83% K−1 @230 K for the composites annealed at 1073 K. In high temperature region, the maximum relative sensitivity of 4.86% K−1@300 K was achieved based on the FIR of I 614 nm /I Mn 4+ in both the as-synthesized composites and those annealed at 1073 K. All the phosphors demonstrated excellent repeatability over 15 recycles. The findings suggested that ZnAl 2 O 4 :Eu3+-ZnTiO 3 :Mn4+ mixed phosphors had significant potential applications in optical thermometers. [ABSTRACT FROM AUTHOR]

Nano‐aluminum, renowned for its remarkable efficacy in augmenting propulsion efficiency and regressive velocity, stands out as a compelling choice for incorporation into heterogeneous propellant compositions. Nevertheless, the considerable expense of this ultrafine aluminum variant, coupled with the inherent hazards associated with conducting propellant trials, may deter extensive allocation of resources and efforts towards the intricate processes of amalgamation, molding, and comprehensive analysis of the combustion characteristics of freshly devised propellant blends. To provide theoretical support for predicting the chemical properties of nano‐Al composite propellant, we establish a numerical framework to study the combustion characteristics under the working environment of a solid rocket motor. A new five‐step kinetic mechanism is developed in this model to describe the reaction process in the gas phase while accounting for heat conduction, radiative effects, and non‐planar moving surfaces. The comparison between our theoretical work and experimental results confirms that making no distinction among Al particle sizes below 3 μm is reasonable. Finally, the effects of nano‐Al on combustion, burning rate variation, and temperature sensitivity are analyzed in detail. [ABSTRACT FROM AUTHOR]

High-speed global surface temperature distributions and heat flux measurements on the Initial Concept 3.X vehicle (IC3X) model were investigated at the UTSA Mach 7 wind tunnel, examining angles of attack of 0° and 5° at a freestream unit Reynolds number (Re) ~7 × 106 m−1. A ruthenium-based, fast-responding, temperature-sensitive paint (fast-TSP) prepared in-house was applied to a 7.1% scale model of the vehicle. Static calibration was performed to convert the intensity measurements into surface temperature values. The surface temperatures and derived heat flux fields conformed to the predicted trends, which was corroborated by Schlieren flow visualization. Notably, the average surface temperature variation was identified to range from 6 to 34 K at a 0° angle of attack and from 11 to 44 K at a 5° angle of attack, with the most pronounced gradient detected at the stagnation point. Additional measurements provided a detailed thermal assessment of the model, including estimations of the stagnation point heat flux, the convective heat transfer coefficient, and the modified Stanton number. Statistical and time series analyses of the data collected revealed the absence of prevailing unsteady phenomena, suggesting that the tested design geometry is well suited for hypersonic flight applications. These experimental outcomes not only shed light on the aerothermodynamics experienced during high-speed flight but also underscore the effectiveness of fast-TSP in capturing both quantitative and qualitative thermal data. [ABSTRACT FROM AUTHOR]

Inspired by human skin, soft sensors that are capable of sensing various external signals have been an active area of research. However, the vast majority of the developed soft sensors still lag far behind human skin in terms of multimodal sensing capability. Herein, this work reports on a multimodal soft sensor that can decouple thermal and mechanical signals. The sensor is made of poly(ethylene glycol) gel (PEGgel) containing ionic liquid, which is stretchable and transparent and shows decent strain and temperature sensing performances. Importantly, analysis of the ion relaxation dynamics shows that the charge relaxation time and capacitance change of the sensor are independently sensitive to the variations of temperature and mechanical deformation, respectively. By measuring the charge relaxation time and capacitance, the thermal and mechanical signals detected by the PEGgel sensor can be nicely decoupled without signal interference. Such a multimodal soft sensor may serve as a starting point for the development of lifelike soft sensors for high‐tech applications in a variety of fields such as soft robotics, the internet of things, and human–machine interaction. [ABSTRACT FROM AUTHOR]

In the past few decades, the injection and transporting characteristics of charge carriers in organic light emitting diodes (OLEDs) have been analyzed using hole‐only and electron‐only devices (HODs and EODs). However, such methods cannot fully explain the dynamic characteristics of OLEDs such as charge accumulation and recombination. In this study, we well‐established the combination of modulus spectroscopy and capacitance‐voltage measurement and applied it to describe the carrier dynamics in OLED devices. [ABSTRACT FROM AUTHOR]

The menthol sensor transient receptor potential melastatin-8 (TRPM8) can be activated by cold and, thus, serves as a biothermometer in a primary afferent sensory neuron for innocuous-to-noxious cold detection. However, the precise structural origins of specific temperature thresholds and sensitivity have remained elusive. Here, a grid thermodynamic model was employed, to examine if the temperature-dependent noncovalent interactions found in the 3-dimensional (3D) structures of thermo-gated TRPM8 could assemble into a well-organized fluidic grid-like mesh network, featuring the constrained grids as the thermorings for cold-sensing in response to PIP2, Ca2+ and chemical agents. The results showed that the different interactions of TRPM8 with PIP2 during the thermal incubation induced the formation of the biggest grids with distinct melting temperature threshold ranges. Further, the overlapped threshold ranges between open and pre-open closed states were required for initial cold activation with the matched thermo-sensitivity and the decrease in the systematic thermal instability. Finally, the intact anchor grid near the lower gate was important for channel opening with the active selectivity filter. Thus, PIP2-dependent thermorings in TRPM8 may play a pivotal role in cold sensing. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

Accurately predicting the feedback mechanisms between forest ecosystem carbon cycling and climate change is crucial for effective climate mitigation. Understanding soil organic carbon (SOC) responses to the combined impacts of plant biomass, litter, and nitrogen deposition, especially regarding temperature sensitivity, is essential but remains poorly understood. We conducted incubation experiments using buried black soil from a cool temperate deciduous broad-leaved forest in Japan, which has high C content and a highly stable molecular structure. The stepwise addition of glucose and a temperature increase from 15 to 35 °C accelerated SOC mineralization by 74.0 mg C kg−1 with a positive priming effect (PE) during the 49-day incubation period, while the simultaneous addition of nitrogen had no significant effect on this phenomenon, with SOC mineralization measured at 75.5 mg C kg−1. Conversely, glucose mineralization was significantly accelerated by 10%, from 241.0 to 261.3 mg C kg−1, by stepwise nitrogen addition and temperature increase. Under the combined impacts, the Q10 value of the soil increased significantly from 1.6 to 2.0 compared to that in the unmodified conditions, primarily due to the stepwise addition of glucose. We also found a strong positive correlation between activation energy (Ea) and Q10. This result strongly supports the carbon quality–temperature (CQT) hypothesis. These results likely stem from interactions between SOC quality and carbon availability, suggesting that, in the future, climate change is likely to have a positive feedback effect, especially on buried black soils. [ABSTRACT FROM AUTHOR]

The transition from vegetative to reproductive growth in rice (Oryza sativa) is mainly regulated by photoperiod and temperature; however, it remains unclear how photoperiod-insensitive (photo-In) early heading rice varieties make this transition. Vegetative growth consists of a basic vegetative phase (BVP) and a photoperiod-sensitive phase (PSP). A certain duration of the BVP is required prior to the PSP, which varies according to daylength conditions. PSP duration is conventionally used as a parameter of photoperiod sensitivity, but this is not applicable to photo-In rice varieties. Here, we aimed to characterize the PSP in photo-In rice varieties. We examined four photo-In varieties and photoperiod-sensitive (photo-Se) varieties grown in four controlled environments, evaluating the lengths of their growth phases based on the turning point of the interval of leaf emergence and panicle initiation (PI). The photo-In varieties had an extremely short PSP, regardless of daylength, compared with the photo-Se varieties. Low temperature uniformly prolonged all growth stages in the photo-In varieties but led to a much longer PSP in the photo-Se varieties. The photo-In varieties, each carrying a non-functional allele of Ghd7, lost the ability to suppress PI, resulting in early heading. Hemi-knockout plants at the Ghd7 locus demonstrated the earlier heading than the wild-type plant due to shortening of PSP. Our results suggest that the photo-In varieties begin PI immediately after the end of the BVP, but their flowering is not a temperature-dependent process.

The menthol sensor transient receptor potential melastatin-8 (TRPM8) can be activated by cold and, thus, serves as a biothermometer in a primary afferent sensory neuron for innocuous-to-noxious cold detection. However, the precise structural origins of specific temperature thresholds and sensitivity have remained elusive. Here, a grid thermodynamic model was employed, to examine if the temperature-dependent noncovalent interactions found in the 3-dimensional (3D) structures of thermo-gated TRPM8 could assemble into a well-organized fluidic grid-like mesh network, featuring the constrained grids as the thermorings for cold-sensing in response to PIP2, Ca2+ and chemical agents. The results showed that the different interactions of TRPM8 with PIP2 during the thermal incubation induced the formation of the biggest grids with distinct melting temperature threshold ranges. Further, the overlapped threshold ranges between open and pre-open closed states were required for initial cold activation with the matched thermo-sensitivity and the decrease in the systematic thermal instability. Finally, the intact anchor grid near the lower gate was important for channel opening with the active selectivity filter. Thus, PIP2-dependent thermorings in TRPM8 may play a pivotal role in cold sensing.

The fresh carbon (C) induced priming effect (PE) on soil organic C (SOC) decomposition is critical for global C cycling. Climate warming could raise absorptive roots production and turnover, and then increase the input of absorptive roots litter (ABRL). Therefore, it is urgent to understand the PE induced by ABRL under warming. We conducted a 210-day experiment by adding ABRL of Cunninghamia lanceolata into a C4 soil and incubating them at 19 °C and 23 °C. We found that adding ABRL caused positive PE throughout the incubation. At the early stage (ES: first 30 days), labile C compounds dominated the decomposition of ABRL, significantly higher dissolved organic C (DOC), microbial biomass C (MBC), and absolute hydrolase activities were found in the ABRL treatment than in the control. These results supports that labile C inputs stimulating microbial growth, enzyme activities and cause positive PE via co-metabolic. At the later stage (LS: after 180 days), the release of structural C compounds dominated the decomposition of ABRL, a significantly lower available nitrogen (N) and a significantly higher specific potential N-acquisition (Nacq) enzymes were found in the ABRL treatment than in the control. These results suggests that microbes utilizing the C as energy to increase Nacq enzymes to decompose SOC for N mining under N limitation induced positive PE. Warming significantly increased the PEs at both stages. At the ES, warming increased the MBC at the cost of DOC, suggesting that warming intensifies the microbial co-metabolism. At the LS, warming significantly decreased the available N and increases the absolute potential oxidases activities, suggesting an increased N limitation and oxidation for N-rich recalcitrant SOC, i.e., a promoted microbial N mining. Nevertheless, we did not observe a significant effect of ABRL addition on the temperature sensitivity of SOC decomposition compared to the control. This study provides a valuable insight that warming could consistently increase the ABRL induced PE but through different microbial mechanisms along with the decomposition processing.

The soil microbiome is a driver of nitrous oxide (N2O) emissions in terrestrial ecosystems. Identifying the core microbiome of N2O emissions and its temperature sensitivity from trillions of soil microorganisms is a great challenge and is essential to improving the predictability of soil-climate feedback related to increasing temperature. Here, the integrated soil microbiome covering archaeal, bacterial, fungal, algal, and microfaunal communities was studied to disengage the potential linkage with its N2O emissions and its temperature sensitivity in paddy fields by hunting for core species pairs. The results showed that between-group interactions of core bacterial and archaeal members and the within-group interactions of core bacterial members jointly contributed to the N2O emissions and its temperature sensitivity. The contribution of between-group interactions (32 to 33%) was greater than that of within groups (10 to 18%). These results suggested that N2O emissions and their fluctuations related to climate warming are affected by the within- and between-group interactions of the soil microbiome. Our results help advance the knowledge on the importance of microbial keystone species and network associations in controlling N2O production and their responses to increasing temperature. IMPORTANCE Soil microorganisms drive emissions of nitrous oxide from soils; this is a powerful greenhouse gas and the dominant ozone-depleting agent. N2O emissions can be partly predicted from soil properties and specific microbial groups, whereas a possible role of below-ground microbial interactions has largely been overlooked. Here, the integrated soil microbiome covering archaeal, bacterial, fungal, algal, and microfaunal communities was studied to disengage the potential linkage with the N2O emissions and temperature sensitivity of the microbiome in paddy fields by hunting for core species pairs. The results showed that between-group interactions of core bacterial and archaeal members and the within-group interactions of core bacterial members jointly contributed to the N2O emissions. The contribution of between-group interactions (32 to 33%) was greater than that of within-group interactions (10 to 18%). Our results help advance the knowledge on the importance of microbial keystone species and interactions in controlling N2O production and their responses to increasing temperature.

In order to develop a highly sensitive flexible temperature sensor,a temperature sensitive conductive core-spun yarn constructed by conductive polymer and carbon nanomaterials was prepared by electrospinning. The morphology structure,electrical property,temperature sensitivity,reusability,humidity resistance and bending deformation interference resistance of the prepared temperature sensitive conductive core-spun yarn were tested. The results showed that the conductivity of the temperature sensitive conductive core-spun yarn was the highest and reaching 1 099.53 S/m when the mass fraction of PAN was 12 % and the mass fraction of rGO was 1.5 %. It showed better electrical property.The temperature sensitive conductive core-spun yarn prepared in the experiment had a high sensitivity response of 1.6 s compared with water of a difference of 1 °C at room temperature. The temperature sensitive conductive core-spun yarn prepared in the experiment had better humidity resistance and better bending deformation resistance. It is considered that the temperature sensitive conductive core-spun yarn prepared in the experiment is expected to replace the traditional metal conductive yarn.It has wide application prospect in wearable intelligent device, intelligent garment, temperature inspection and so on. [ABSTRACT FROM AUTHOR]

Circadian regulation and temperature dependency are important orchestrators of molecular pathways. How the integration between these two drivers is achieved, is not understood. We monitored circadian-and temperature-dependent effects on transcription dynamics of cold-response protein RNA Binding Motif 3 (Rbm3). Temperature changes in the mammalian master circadian pacemaker, the suprachiasmatic nucleus (SCN), induced Rbm3 transcription and regulated its circadian periodicity, whereas the core clock gene Per2 was unaffected. Rbm3 induction depended on a full Brain And Muscle ARNT-Like Protein 1 (Bmal1) complement: reduced Bmal1 erased Rbm3 responses and weakened SCN circuit resilience to temperature changes. By focusing on circadian and temperature dependency, we highlight weakened transmission between core clock and downstream pathways as a potential route for reduced circadian resilience. [ABSTRACT FROM AUTHOR]

Porous asphalt pavements are widely used in rainy and wet areas for their skid resistance, noise reduction, runoff minimization and environmental sustainability. Long-term moisture vapor erosion and the destabilization of large pore structures can easily result in pavement problems such as fragmentation, spalling, cracking, and excessive permanent deformation. To this end, four different preventive maintenance materials, including the rejuvenation (RJ), cohesion reinforcement (CEM), polymerization reaction, and emulsified asphalt (EA) types, were selected in this paper to improve the high-viscosity porous asphalt pavement. The effects of the different preventive maintenance materials on the temperature sensitivity, rheological properties and fatigue performance of high-viscosity modified asphalt were evaluated through temperature sweep, frequency sweep, multi-stress creep recovery (MSCR), linear amplitude sweep (LAS), and bending beam rheometer (BBR) tests. The results showed that the four preventive maintenance materials exhibit different enhancement mechanisms and effects. RJ improves the fatigue properties, deformation resistance and low-temperature cracking resistance of aged asphalt by adding elastomeric components; CEM materials are more conducive to increasing the low-temperature crack resistance of aged asphalt; while GL1 and EA improve the viscoelastic behavior of aged asphalt, but the effect of the dosing ratio needs to be considered. [ABSTRACT FROM AUTHOR]

In this study, the Bi3+ doped LuBaZn 3 GaO 7 fluorescent powder was produced using a high-temperature solid-state technique, and its long afterglow luminescence and dynamic anti-counterfeiting capabilities were thoroughly examined. Under the ultraviolet (UV) light excitation, the LuBaZn 3 GaO 7 host exhibits broadband self-activated emission band peak at 594 nm, attributed to the O-vacancies. Upon Bi3+ doping, the phosphor produces a narrow emission band in the 350–450 nm wavelength range, which is caused by the 3P 1 –1S 0 transition of the Bi3+ ions in the Ba2+ site. Remarkably, oxygen vacancy-induced electronic localization around the Bi3+ ions increases the emission intensity of LuBaZn 3 GaO 7 :0.01Bi3+ around ten times that of LuBaZn 3 GaO 7 between 450 and 850 nm wavelength. With the variation in excitation light wavelength, the intensity of the two emission bands of LuBaZn 3 GaO 7 : Bi3+ changed accordingly, exhibiting multi-color luminescence. While the excitation was removed after 3-min irradiation, LuBaZn 3 GaO 7 : Bi3+ phosphors continued to emit for 10 min. Moreover, the phosphor emission has good temperature-sensitive characteristics based on the fluorescence intensity ratio (FIR) of the emission bands of Bi3+ ions and host. Hence, an optical thermometry with high-temperature sensitivity was constructed. Consequently, it can be concluded that fluorescent powder has the potential to be applied in the fields of fluorescence temperature measurement and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Pharmaceutical University is the property of Shenyang Pharmaceutical University 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.)

Structural Health Monitoring (SHM) is important for the prevention and detection of corrosion, leaks and other damage types that could compromise their pose significant environmental, structural integrity and safety risks. This simulation work concentrates on the SHM of underground pipelines using polyimide coated LPFG-FBG-LPFG sensors; this simultaneous modeling focuses on temperature and pressure sensitivity effects. By using MATLAB coding, this work studies and investigates the sensors performance and modeling techniques. The sensitivity of temperature was calculated to be 3.7 nm/°C. While the pressure sensitivity was calculated to be 5.3 nm/Pa. The proposed sensor shows good linearity behavior and the coefficients of determination were found to be 0.9939 and 0.9878 for temperature and pressure sensors, respectively. The main findings of the current work demonstrate that the polyimide coated LPFG-FBG-LPFG sensors are highly sensitive and stable, making them suitable for long-term monitoring of pipeline structural health. The proposed simultaneous modeling regarding temperature and pressure effects by using MATLAB coding provides a reliable and accurate approach for diagnosing and detecting and pipeline anomalies. This model will enable the real time detection and diagnosis of underground pipelines damage or leaks, hence enhancing their safety, reliability, and reducing costs of maintenance aspects. [ABSTRACT FROM AUTHOR]

The sterile insect technique can suppress and eliminate population outbreaks of the Australian horticultural pest, Bactrocera tryoni, the Queensland fruit fly. Sterile males mate with wild females that produce inviable embryos, causing population suppression or elimination. Current sterile insect releases are mixed sex, as the efficient removal of unrequired factory-reared females is not yet possible. In this paper, we assessed the known Drosophila melanogaster temperature-sensitive embryonic lethal alleles shibire (G268D, shits1) and RNA polymerase II 215 (R977C, RpII215ts) for potential use in developing B. tryoni genetic sexing strains (GSS) for the conditional removal of females. Complementation tests in D. melanogaster wild-type or temperature-sensitive genetic backgrounds were performed using the GAL4–UAS transgene expression system. A B. tryoni wild-type shibire isoform partially rescued Drosophila temperature lethality at 29°C by improving survivorship to pupation, while expressing B. tryoni shits1 failed to rescue the lethality, supporting a temperature-sensitive phenotype. Expression of the B. tryoni RpII215 wild-type protein rescued the lethality of D. melanogaster RpII215ts flies at 29°C. Overexpressing the B. tryoni RpII215ts allele in the D. melanogaster wild-type background unexpectedly produced a dominant lethal phenotype at 29°C. The B. tryoni shibire and RpII215 wild-type alleles were able to compensate, to varying degrees, for the function of the D. melanogaster temperature-sensitive proteins, supporting functional conservation across species. Shibire and RpII215 hold potential for developing insect strains that can selectively kill using elevated temperatures; however, alleles with milder effects than shits1 will need to be considered. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) mineralization is a key component of the global carbon cycle. Its temperature sensitivity Q10 (which is defined as the factor of change in mineralization with a 10 °C temperature increase) is crucial for understanding the carbon cycle-climate change feedback but remains uncertain. Here, we demonstrate the universal control of carbon quality-availability tradeoffs on Q10. When carbon availability is not limited, Q10 is controlled by carbon quality; otherwise, substrate availability controls Q10. A model driven by such quality-availability tradeoffs explains 97% of the spatiotemporal variability of Q10 in incubations of soils across the globe and predicts a global Q10 of 2.1 ± 0.4 (mean ± one SD) with higher Q10 in northern high-latitude regions. We further reveal that global Q10 is predominantly governed by the mineralization of high-quality carbon. The work provides a foundation for predicting SOC dynamics under climate and land use changes which may alter soil carbon quality and availability. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) is a major global carbon (C) pool vulnerable to ongoing warming, as microbial SOM decomposition and CO2 respiration are sensitive to temperature. We characterized the edaphic characteristics that explain variation in soil C concentration, cycling, and temperature sensitivity (Q10) across two sites of differing elevation, forest community composition, and mineral parent material at Hopkins Memorial Forest, Williamstown, Massachusetts, USA. We found that the upper site maintained significantly higher surface soil C concentration, despite similar litterfall inputs across sites. We found large differences in the fraction of total soil C that is protected from microbial decomposition, with enhanced physical protection in macroaggregate-rich, upper site soils. Upper site plots maintain a higher relative abundance of plants producing lignin-rich litter, which may fuel aggregate formation and SOM protection. Experimental addition of glucose, vanillin, and lignin substrates produced broadly conserved respiratory responses across sites, suggesting that microbial communities maintain similar decomposition capacity, although lignin addition induced slightly elevated respiration responses in upper relative to lower site plots. Seasonal Q10 of soil respiration was higher at the upper site and increased with soil potassium (K+) availability across plots, potentially reflecting K+ constraints on autotrophic and heterotrophic metabolic activity. Our findings suggest that variation in the extent of physical protection of soil C, particularly through macroaggregate formation, is an important mechanism for long-term soil C storage at the site. Despite enhanced SOM physical protection at the upper site, the higher temperature sensitivity of soil respiration may reduce soil C in the context of future warming. [ABSTRACT FROM AUTHOR]

Nitrogen (N) additions often decrease soil respiration and increase soil organic carbon (C) stock. However, it is unclear how microbial substrates may shift with N additions and increasing temperature. Leveraging 12 years of N fertilization experiments and the associated shift in the dominant vegetation from C4 to C3, we explored the δ13C‐CO2 and temperature sensitivities of respired CO2 and extracellular enzyme activities in control and fertilized soils. N additions increased cellulose‐decaying extracellular enzyme activity while respiration remained similar between the control and fertilized soils. Temperature sensitivity of cellulose‐decaying extracellular enzyme activity decreased with the N additions. The δ13C‐CO2 data reveal that, as temperature increased, microbes in fertilized soils changed their dominant substrate from bulk soil organic C to plant litterfall. Our results suggest that long‐term N fertilization imposed C limitation on microbes, leading to enhanced microbial efforts to acquire C. This study highlights how long‐term N additions can promote the relative preservation of organic C in mineral soil while litterfall, the precursor to mineral‐associated C, is increasingly decayed as temperatures increase. [ABSTRACT FROM AUTHOR]

The indoor constant temperature culture method was adopted, and the 40-year-old tea garden soil applied with biochar-based fertilizer (BF) and without biochar-based fertilizer (CK) were selected as the research objects. Three different temperature scenarios were set at 15℃, 25℃ and 35℃, and the soil organic carbon (SOC) mineralization characteristics were continuously monitored and the temperature sensitivity of SOC mineralization was analyzed. It will provide reference for evaluating carbon sequestration emission reduction and obstacle reduction in aged tea gardens. The results showed that: (1) biochar-based fertilizer increased the pH and SOC content of tea garden soil under the temperature variation. At 15℃, 25℃ and 35℃, compared with CK treatment, the soil pH of BF treatment increased by 0.45, 0.07 and 0.28, respectively. The SOC content of BF treatment increased by 22.19%, 16.65% and 25.50%, respectively. (2) Biochar-based fertilizer increased the SOC accumulative mineralization amount, mineralization potential (CS) and soil respiration intensity in tea gardens under temperature change, showing a positive priming effect on SOC mineralization. At 15℃, 25℃ and 35℃, compared with CK treatment, the accumulated SOC mineralization amount of BF treatment increased by 15.61%, 46.51% and 36.89%, respectively. The CS value of BF treatment first increased and then decreased with rising temperature. Compared with 15℃ and 35℃, the CS value of BF treatment at 25℃ increased by 147.11% and 29.21% respectively. (3) Biochar-based fertilizer decreased the temperature sensitivity of SOC mineralization in tea gardens under increasing temperature. In the temperature range of 25-35℃, the Q10 (temperature sensitivity of soil organic carbon mineralization) value of BF treatment decreased by 6.25% compared with CK treatment. The Q10 value of BF treatment in the temperature range of 25-35℃ decreased by 25% compared with the Q10 value in the temperature range of 15-25℃. The results indicated that the application of biochar-based fertilizer can effectively improve the physical and chemical properties of the 40-year-old tea garden soil, increase soil carbon sequestration, and improve the stability of the soil carbon pool in response to temperature changes in the tea garden. Biochar-based fertilizer is conducive to optimizing the sustainable production management of low-yield and aging tea gardens. [ABSTRACT FROM AUTHOR]

In optical fiber sensing systems based on fiber Bragg gratings (FBGs), there are numerous parameters that significantly limit the overall sensing performance. In this study, the effects of FBG parameters such as grating length, Bragg wavelength, and reflection rate on temperature sensitivity have been investigated considering there are no strain effects along the length of the grating. For this purpose, the OptiSystem program has been utilized to design an FBG-based sensing system, which is a relevant approach for simulating and analyzing the performance of FBGs. For temperature variations in the range of 1–120 °C, variations of wavelength shift and grating length have been obtained between 14 and 1680 pm and between 0.1 and 100 mm, respectively. It has been observed that the grating length changes have no direct impact on the temperature sensitivity. On the other hand, a 1 °C variation in temperature causes a wavelength change of ~ 14 pm. Furthermore, temperature sensitivities have been found to be 3.66 pm/°C, 4.58 pm/°C, 5.50 pm/°C, 9.2 pm/°C, 14 pm/°C and 18.4 pm/°C for the Bragg wavelengths of 400 nm, 500 nm, 600 nm, 1000 nm, 1550 nm and 2000 nm, respectively. Moreover, the change in temperature sensitivity depending on Bragg wavelength has been computed as ~ 9.15 × 10–3 pm/°C(nm)−1. For the reflection rate variations in the range of 0.001–0.99%, temperature sensitivity has taken the value of ~ 14 pm/°C at 100 °C whilst the reflected powers have varied from 11.1 to 42 dBm. Moreover, a change in temperature sensitivity with reflection rate has been acquired as ~ 0.021 pm/°C(%)−1. [ABSTRACT FROM AUTHOR]

Soil carbon (C) cycling plays a critical role in regulating global C budget and atmospheric CO2 concentrations. The ongoing global warming potentially accelerates soil C loss induced by microbial respiration (MR) and makes soil a large C source to the atmosphere. Quantifying the drivers of MR and its response to rising temperature (also called temperature sensitivity, Q10) should be a high priority to improve the modeling and prediction of terrestrial C cycle under global warming. In this study, we applied a standardized soil sampling along nine gradients from 410 to 1080 m in a subtropical forest in southern China. All soil samples were incubated at varying temperature gradients (10–15–20–25–20–15°C) to measure MR and Q10 every day for three weeks. Then all the measured MR was adjusted by the field temperature of each elevation gradient. Our objectives were to examine the response of MR and Q10 to the environmental change induced by elevational gradients in the subtropical forest and then quantify their main drivers. We totally collected 54 abiotic and biotic factors relative to the MR and Q10. Our results showed that the incubated MR increased from low to high elevation. However, a significant elevation trend of the adjusted MR was not examined after adjusting the field temperature of sampling sites, due to the trade‐off between increasing soil C concentration and declining temperature as elevation increased. We further found that the elevational gradients did not cause significant change in Q10. The variation in Q10 was negatively dominated by soil C quality, which declined nonlinearly along the elevation gradients. This study highlights the trade‐off between environment and biotic factors in determining soil C decomposition along elevational gradients. The uncertainty of MR measurements caused by unifying incubated temperature should not be ignored in future model development. [ABSTRACT FROM AUTHOR]

The rising costs of construction materials, particularly sandcrete blocks, necessitate the exploration of cost-effective alternatives. This study examines the feasibility of incorporating iron filings (IF), a by-product of metal workshops, into hollow sandcrete block production and assesses their performance under harsh conditions. IF was used to replace 5–20 % of the fine aggregate component in blocks at a step of 5 %, mixed at a 1:8 ratio, and sized at 450mm×150mm×225mm. The study evaluated the impact of acidic exposure on the density, sorptivity, and compressive strength of these blocks, as well as their sensitivity to elevated temperatures. The results showed that IF blocks had significantly lower density than non-IF blocks, especially those cured with H₂SO₄. For instance, blocks with 15 % IF and cured in 0.3 mol/dm³ H₂SO₄ had a 13.9 % reduction in density. Despite higher acid concentrations, IF samples demonstrated better sorptivity, absorbing water more slowly than non-IF samples. However, exposure to acidic media reduced compressive strength by 1.9 %–47.8 % for HNO₃ exposure and 0.5 %–42.4 % for H₂SO₄ exposure. None of the acid-exposed blocks met the minimum standards for load-bearing (2.5 MPa) or non-load-bearing walls (2.0 MPa) as per NIS standards. Furthermore, the sensitivity of IF sandcrete blocks to changes in compressive strength under elevated temperatures decreased by almost half, from 0.026 to 0.014 MPa/°C, as the curing period increased from 7 to 28 days. Blocks with 5–15 % IF showed improved compressive strength at temperatures below 150 °C, but strength declined sharply beyond this temperature. By utilising IF, a readily available waste material, the implications of the study are significant for promoting a circular economy in the construction industry. However, the performance of the blocks against durability concerns needs to be improved further before integrating such waste materials into developing sustainable and resilient construction materials