Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusi...Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed slightly.The dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)increased.With the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical<2111>-<1123>rare-earth(RE)textures.The alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening contributions.These results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.展开更多
Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability o...Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported.Herein,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock method.Such a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode materials.Coupled with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°C.Based on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.展开更多
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac...Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines.展开更多
This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junctio...This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.展开更多
The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nit...The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nitrogen-doped carbon fibers loaded with a ternary metal sulf-ide((Fe,Co,Ni)_(9)S_(8))for use as the sulfur host in Li-S batteries.This materi-al was prepared using transfer blot filter paper as the carbon precursor,thiourea as the source of nitrogen and sulfur,and FeCl_(3)·6H_(2)O,CoCl_(2)·6H_(2)O and NiCl_(2)·6H_(2)O as the metal ion sources.It was synthesized by an impreg-nation method followed by calcination.The nitrogen doping significantly in-creased the conductivity of the host,and the metal sulfides have excellent catalytic activities.Theoretical calculations,and adsorption and deposition experiments show that active sites on the surface of FCNS@NCFs selectively adsorb polysulfides,facilitate rapid adsorption and conversion,prevent cathode passivation and inhib-it the polysulfide shuttling.The FCNS@NCFs used as the sulfur host has excellent electrochemical properties.Its initial dis-charge capacity is 1639.0 mAh g^(−1) at 0.2 C and room temperature,and it remains a capacity of 1255.1 mAh g^(−1) after 100 cycles.At−20~C,it has an initial discharge capacity of 1578.5 mAh g^(−1) at 0.2 C,with a capacity of 867.5 mAh g^(−1) after 100 cycles.Its excellent performance at both ambient and low temperatures suggests a new way to produce high-performance low-temper-ature Li-S batteries.展开更多
The use of solar energy is today widely recognized for the green transition but also for addressing societal challenges associated with the rise in global surface temperature. The design of a photovoltaic solar panel ...The use of solar energy is today widely recognized for the green transition but also for addressing societal challenges associated with the rise in global surface temperature. The design of a photovoltaic solar panel field may require an understanding of how solar radiation oscillates with other variables or factors since multiple interactions occur during its transfer within the atmosphere. In this study, three years of the incoming shortwave radiation (SWin) and air temperature (Tair) data acquired within the “Institut de Mathématiques et de Sciences Physiques” were analyzed using the continuous wavelet transform to extract the inherent variability of these signals. The underlying characteristics meaning the timescale of these variabilities as well as the lead-lag relationship between SWin and Tair were also examined. With the wavelet power spectrum, the highest variability was evidenced at the 2 - 8 band period for the SWin, coinciding almost with that of Tair. This suggests that these two signals are well interconnected at this temporal scale. The results obtained with the phase (∅xy) difference analysis, reveal that SWin leads Tair by ~ 23.5˚ on average when (0 ∅xy∅xyi.e., periods ≤ 32 days), Tair increases with an increasing SWin since the lags between these two signals range between 0.09 - 2.30 days. However, when looking at their interdependence at a larger temporal scale (> 32 days), Tair lags SWin. An increase in SWin might not directly imply an increase in Tair. Overall, these findings give insight into complex relationships across scales between the incoming shortwave radiation and air temperature in a tropical humid region of Bénin.展开更多
The objective of this research is to investigate the effects of cosmic ray Forbush Decreases (FDs) exceeding 7% in magnitude, occurring between 1985 and 2016, on upper atmospheric pressure and temperature at Abha and ...The objective of this research is to investigate the effects of cosmic ray Forbush Decreases (FDs) exceeding 7% in magnitude, occurring between 1985 and 2016, on upper atmospheric pressure and temperature at Abha and Tabouk. Employing the super epoch analysis method, the study concentrated on altitudes of 5 km and 10 km, uncovering significant variations. Seasonal and synoptic-scale variations were considered and excluded when necessary across eight 9-day periods. Both locations showed considerable fluctuations in pressure and temperature before and after the events. At 5 km altitude (21 events), Abha experienced more pressure increases both before (9 vs. 7) and after (12 vs. 11) the events compared to Tabouk. For temperature, Abha recorded more increases before the events (5 vs. 1), while Tabouk showed more decreases (19 vs. 15). Post-event, Tabouk had more temperature increases (13 vs. 10). At 10 km altitude (20 events), both regions experienced more decreases than increases in pressure and temperature before the events and more increases afterward. Notably, Abha experienced more pressure increases both 4 days before (9 vs. 7) and after the events (12 vs. 11) than Tabouk. For temperature, Abha recorded more increases before the events (5 vs. 1), while Tabouk showed more decreases (19 vs. 15). Post-event, Tabouk had more temperature increases (13 vs. 10). These findings underscore both similarities and differences in atmospheric responses to FDs between Abha and Tabouk. Both locations exhibited cooling trends before and warming trends after the events, with Tabouk demonstrating a more pronounced warming trend post-event. These results enhance our understanding of the atmospheric dynamics linked to FDs and assist in predicting weather patterns associated with these phenomena.展开更多
Developing reliable adaptation and mitigation strategies to combat climate change is necessary at regional and local scales. The present study analyses the ability of the multi-model ensemble (MME) composed of fourtee...Developing reliable adaptation and mitigation strategies to combat climate change is necessary at regional and local scales. The present study analyses the ability of the multi-model ensemble (MME) composed of fourteen (14) CORDEX-Africa simulations to capture characteristics of the mean temperature for the present day (1979-2005) and associated extremes over Côte d’Ivoire. For this end, the analysis uses the mean variables of the temperature (i.e., minimum temperature (TMIN), mean temperature (TMEAN) and maximum temperature (TMAX)) as well as associated extremes such as intra-period extreme temperature range (ETR), warm spell duration index (HWFI) and warm days index (TX90P) during January-February-March (JFM), April-May-June (AMJ), July-August-September (JAS) and October-November-December (OND) seasons. The results indicate that mean temperature variables (TMIN, TMEAN and TMAX) are underestimated by CORDEX MME in general, except TMEAN in the centre of Côte d’Ivoire. On the other hand, extreme temperature indices are overestimated over Côte d’Ivoire, except ETR in JAS with an underestimation of about 2˚C and TX90P during JAS in the southern part of the country in JFM, AMJ and OND with an underestimation varying between 1% to 4%. In addition, CORDEX MME and observational datasets (CPC and NCEP) have a significant correlation in simulating temperature variables (TMIN, TMEAN, TMIN), while this correlation is not significant in general for extreme temperature, except ETR and HWFI. Furthermore, extreme temperatures (TX90P and HWFI) are characterized by more important interannual variability in the observations CPC and NCEP for ETR. Moreover, mean temperature variables (TMIN, TMEAN, TMAX) show slight interannual variability with respect to the observations CPC and NCEP, which are characterized by the most variability. Overall, CORDEX MME outperforms the seasonal and spatial variability of the temperature and associated extremes over Côte d’Ivoire, although some biases in representing their magnitudes. Thus, the results of the present study will help take appropriate adaptation and mitigation strategies against heatwaves and extreme temperature advent over Côte d’Ivoire as these climate extremes are projected to increase over the country.展开更多
The influence of pouring temperature and mold temperature on the fluidity and hot tearing behavior of Al-2Li-2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloys was investigated by experimental investigation and simulation assessment...The influence of pouring temperature and mold temperature on the fluidity and hot tearing behavior of Al-2Li-2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloys was investigated by experimental investigation and simulation assessment.The results showed that the length of the spiral fluidity sample increases from 302 to 756 mm as the pouring temperature increases from 680 to 740℃,and from 293 to 736 mm as the mold temperature increases from 200 to 400℃.The hot tearing susceptibility(HTS)firstly decreases and then increases with increasing pouring and mold temperatures,which is mainly caused by the oxide inclusion originating from the high activity of Li at excessive pouring temperature.Excessive pouring and mold temperatures easily produce oxide inclusions and holes,leading to a reduction in fluidity and an increase in HTS of the alloy.Combining the experimental and simulation results,the optimized pouring and mold temperatures are~720℃ and~300℃ for the cast Al-Li alloy,respectively.展开更多
This study investigates the compressive and tensile properties of basalt fiber-reinforced concrete (BFRC) after ultra-low-temperature freeze-thaw cycles. Scanning electron microscope (SEM) analysis was conducted to ex...This study investigates the compressive and tensile properties of basalt fiber-reinforced concrete (BFRC) after ultra-low-temperature freeze-thaw cycles. Scanning electron microscope (SEM) analysis was conducted to examine the deterioration mechanisms caused by freeze-thaw cycles and sulfate erosion. The results show that compressive and tensile strengths increase with basalt fiber dosage. The optimal dosage is 0.2%. With longer exposure to sulfate erosion, both strengths decline significantly. Basalt fibers effectively bridge cracks, control expansion, enhance compactness, and improve concrete performance. Ultra-low-temperature freeze-thaw cycles and sulfate erosion cause rapid crack growth. Sulfate erosion produces crystallization products and expansive substances. These fill cracks, create pressure, and damage the internal structure. Freezing and expansion forces further enlarge voids and cracks. This provides space for expansive substances, worsening concrete deterioration and reducing its performance.展开更多
In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining me...In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining method coupled with a temperature compensation strategy.To improve performance,a T-type device with a 1μm gap was fabricated resulting in an average sensitivity of 1.10 V/lgPa,which was 2.89 times larger than that(0.38 V/lgPa)of a L-type device with a 100μm gap.Additionally,FEA simulations were conducted,analyzing the influence of heater temperature on sensitivity and the attenuation of sensitivity across varying ambient temperatures.A semi-empirical theoretical mode was derived for performance prediction,demonstrating strong alignment with experimental results,underscoring its effectiveness in compensating for sensitivity attenuation.Building on the foundation,the device’s performance under different ambient temperatures was characterized and effectively compensated in two distinct operational modes:constant temperature mode and constant temperature difference mode(the whole range temperature compensation error can be controlled within 2.5%).Finally,the short-time stability(variation level is approximately 1 mV),noise floor(Vrms=384μV)and detection limit(0.07 Pa@1 Hz)of the device were characterized,confirming its suitability for practical implementation.展开更多
Three-dimensional ocean subsurface temperature and salinity structures(OST/OSS)in the South China Sea(SCS)play crucial roles in oceanic climate research and disaster mitigation.Traditionally,real-time OST and OSS are ...Three-dimensional ocean subsurface temperature and salinity structures(OST/OSS)in the South China Sea(SCS)play crucial roles in oceanic climate research and disaster mitigation.Traditionally,real-time OST and OSS are mainly obtained through in-situ ocean observations and simulation by ocean circulation models,which are usually challenging and costly.Recently,dynamical,statistical,or machine learning models have been proposed to invert the OST/OSS from sea surface information;however,these models mainly focused on the inversion of monthly OST and OSS.To address this issue,we apply clustering algorithms and employ a stacking strategy to ensemble three models(XGBoost,Random Forest,and LightGBM)to invert the real-time OST/OSS based on satellite-derived data and the Argo dataset.Subsequently,a fusion of temperature and salinity is employed to reconstruct OST and OSS.In the validation dataset,the depth-averaged Correlation(Corr)of the estimated OST(OSS)is 0.919(0.83),and the average Root-Mean-Square Error(RMSE)is0.639°C(0.087 psu),with a depth-averaged coefficient of determination(R~2)of 0.84(0.68).Notably,at the thermocline where the base models exhibit their maximum error,the stacking-based fusion model exhibited significant performance enhancement,with a maximum enhancement in OST and OSS inversion exceeding 10%.We further found that the estimated OST and OSS exhibit good agreement with the HYbrid Coordinate Ocean Model(HYCOM)data and BOA_Argo dataset during the passage of a mesoscale eddy.This study shows that the proposed model can effectively invert the real-time OST and OSS,potentially enhancing the understanding of multi-scale oceanic processes in the SCS.展开更多
High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)ban...High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)band—along with microwave stealth and efficient thermal management at high temperatures,remains a significant challenge.Here,we propose a strategy that integrates an IR-selective emitter(Mo/Si multilayer films)and a microwave metasurface(TiB2–Al2O3–TiB2)to enable multi-infrared band stealth,encompassing mid-wave infrared(MWIR),long-wave infrared(LWIR),and SWIR bands,and microwave(X-band)stealth at 700℃,with simultaneous radiative cooling in non-atmospheric window(5–8μm).At 700℃,the device exhibits low emissivity of 0.38/0.44/0.60 in the MWIR/LWIR/SWIR bands,reflection loss below−3 dB in the X-band(9.6–12 GHz),and high emissivity of 0.82 in 5–8μm range—corresponding to a cooling power of 9.57 kW m^(−2).Moreover,under an input power of 17.3 kW m^(−2)—equivalent to the aerodynamic heating at Mach 2.2—the device demonstrates a temperature reduction of 72.4℃ compared to a conventional low-emissivity molybdenum surface at high temperatures.This work provides comprehensive guidance on high-temperature stealth design,with far-reaching implications for multispectral information processing and thermal management in extreme high-temperature environments.展开更多
Luminescent materials with tunable emission wavelengths/colors hold great potential for smart response devices,data security,sensors,and so on.However,development of stimuli-responsive luminescent materials with tradi...Luminescent materials with tunable emission wavelengths/colors hold great potential for smart response devices,data security,sensors,and so on.However,development of stimuli-responsive luminescent materials with traditional organic or inorganic luminophores remains challenging due to their lack of tunability.Herein,we report the tunable luminescence and ratiometric temperature sensing applications with a europium-organic cage(Eu4L4)featuring concentration-dependent hierarchical self-assembly behavior.Notably,white light emission was achieved by adjusting the equilibrium ratio between the red-emissive cage monomer and cyan-emissive cage aggregate.Taking advantage of the dual emissive nature of the system,ratiometric luminescent temperature sensing has also been achieved,exhibiting a sensitivity of 2.04% and linear correlation coefficient of 0.997 from 250 to 320 K.展开更多
Tropical mountain peatlands in Brazil’s Southern Espinhaço Range are vital ecosystems,acting as carbon reservoirs,hydrological buffers,and biodiversity hotspots while sustaining traditional livelihoods and prese...Tropical mountain peatlands in Brazil’s Southern Espinhaço Range are vital ecosystems,acting as carbon reservoirs,hydrological buffers,and biodiversity hotspots while sustaining traditional livelihoods and preserving paleoenvironmental records.Despite their importance,peatlands outside protected areas face degradation by grazing and fires,threatening their ability to regulate ecosystem processes sensitive to temperature,such as greenhouse gas emissions,water cycling,biological activity,and organic matter decomposition.Since 2016,we have monitored peat temperatures in two contrasting peatlands–one preserved(within a protected area)and one disturbed(outside the protected area)–to understand how anthropogenic disturbances and climate variability impact these fragile ecosystems.Seasonal patterns dominated temperature variation,accounting for 60% of air and 81%–92% of peatland temperature variation.However,average temperatures and amplitudes differed between peatlands and depths.Interannual variability revealed stronger trends in the disturbed peatland,where a 1℃ increase in air temperature caused the trend to increase 0.70℃–0.87℃ on average at depths of 0.85 m–0.92 m.By contrast,the preserved peatland showed smaller increases(0.20℃–0.24℃)at comparable depths(1.06 m–1.24 m),suggesting a greater resilience.Temperature variation in the monitored peatlands was majorly driven by seasonal patterns,as revealed by time series decomposition and sinewave fit.Average temperature and amplitude varied between the two peatlands and among sampling sites,reflecting differences in environmental conditions and measurement depth.Interannual variability also exhibited distinct effects between peatlands and monitoring sites.The time series trend component showed more pronounced fluctuations at shallower depths and in the disturbed peatland.For every 1℃ increase in the trend component of the air temperature,the trend component of the peatland time series increased by 0.70℃ and 0.87℃on average at depths of 0.85 m and 0.92 m,respectively,in the disturbed peatland.In contrast,the preserved peatland exhibited smaller increases of 0.20℃ and 0.24℃ at comparable depths(1.06 m and 1.24 m).These findings highlight the potential for feedback responses between peatland disturbance and climate change,threatening their critical role in regulating carbon and water cycles.Expanding long-term monitoring,strengthening conservation efforts,and raising public awareness are essential to safeguard the ecosystem services provided by tropical mountain peatlands.展开更多
In this paper,a dual Mach-Zehnder interferometer for measuring both temperature and strain is proposed and verified by experiments.The sensor configuration involves cascading a four-core fiber and a double-clad fiber ...In this paper,a dual Mach-Zehnder interferometer for measuring both temperature and strain is proposed and verified by experiments.The sensor configuration involves cascading a four-core fiber and a double-clad fiber between two single-mode fibers.By exploiting the different responses of the two Mach-Zehnder interferometers to temperature and strain,we construct a matrix using two selected resonance dips from the transmission spectra,so that both temperature and strain can be measured simultaneously.The experimental results show the sensor’s remarkable performance,with the maximum temperature sensitivity of-94.2 pm/℃and the maximum strain sensitivity of 2.68 pm/με.The maximum temperature error and strain error are found to be±0.35℃and±4.8με,respectively.Compared with other optical fiber sensors,the sensor has high sensitivity,a simple structure,and ease to manufacture and implement,making it a structure choice for applications in quality inspection of materials.展开更多
Leaf cutting ants of the genus Atta cultivate fungal gardens,carefully modifying environmental conditions to maintain optimal temperature for fungal growth.Antennal nerves from Atta are highly temperature sensitive,bu...Leaf cutting ants of the genus Atta cultivate fungal gardens,carefully modifying environmental conditions to maintain optimal temperature for fungal growth.Antennal nerves from Atta are highly temperature sensitive,but the underlying molecular sensor is unknown.Here,we utilize Atta texana(Texas leaf cutter ant)to investigate the molecular basis of ant temperature sensation and how it might have evolved as the range expanded northeast across Texas from ancestral populations in Mexico.We focus on transient receptor potential(TRP)channel genes,the best characterized temperature sensor proteins in animals.Atta texana antennae express 6 of 13 Hymenopteran TRP channel genes and sequences are under a mix of relaxed and intensified selection.In a behavioral assay,we find A.texana workers prefer 24℃(range 21−26℃)for fungal growth.There was no evidence of regulatory evolution across a temperature transect in Texas,but instead Hymenoptera-specific TRPA(HsTRPA)expression highly correlated with ambient temperature.When expressed in vitro,HsTRPA from A.texana is temperature activated with Q10 values exceeding 100 on initial exposure to temperatures above 33℃.Surprisingly,HsTRPA also appears to be activated by cooling,and therefore to our knowledge,the first non-TRPA1 ortholog to be described with dual heat/cold activation and the first in any invertebrate.展开更多
Implantable temperature sensors are revolutionizing physiological monitoring and playing a crucial role in diagnostics,therapeutics,and life sciences research.This review classifies the materials used in these sensors...Implantable temperature sensors are revolutionizing physiological monitoring and playing a crucial role in diagnostics,therapeutics,and life sciences research.This review classifies the materials used in these sensors into three categories:metal-based,inorganic semiconductor,and organic semiconductor materials.Metal-based materials are widely used in medical and industrial applications due to their linearity,stability,and reliability.Inorganic semiconductors provide rapid response times and high miniaturization potential,making them promising for biomedical and environmental monitoring.Organic semiconductors offer high sensitivity and ease of processing,enabling the development of flexible and stretchable sensors.This review analyzes recent studies for each material type,covering design principles,performance characteristics,and applications,highlighting key advantages and challenges regarding miniaturization,sensitivity,response time,and biocompatibility.Furthermore,critical performance parameters of implantable temperature sensors based on different material types are summarized,providing valuable references for future sensor design and optimization.The future development of implantable temperature sensors is discussed,focusing on improving biocompatibility,long-term stability,and multifunctional integration.These advancements are expected to expand the application potential of implantable sensors in telemedicine and dynamic physiological monitoring.展开更多
This study investigates the effect of different in situ conditions like flaw infill,heat-treatment temperatures,and sample porosities on the anisotropic compressive response of jointed samples with an impersistent fla...This study investigates the effect of different in situ conditions like flaw infill,heat-treatment temperatures,and sample porosities on the anisotropic compressive response of jointed samples with an impersistent flaw.Jointed samples of different porosities are prepared by mixing Plaster of Paris(POP)with different water contents,i.e.60%(i.e.for lower porosity)and 80%(i.e.for higher porosity).These samples are grouted with different infill materials,i.e.un-grouted,cement and sand-cement(3:1)-bio-concrete(SCB)mix and subsequently subjected to different temperatures,i.e.100℃,200℃ and 300℃.The results reveal the distinct stages in the stress-strain responses of samples characterized by initial micro-cracks closure,elastic transition,and non-linear response till peak followed by a post-peak behaviour.The un-grouted samples exhibit their lowest strength at 30°joint orientation.The ratios of maximum to minimum strength are 3.11 and 3.22 with varying joint orientations for lower and higher porosity samples,respectively.Strengths of cement and SCB mix grouted samples are increased for all joint orientations ranging between 16.13%-69.83%and 18.04%-73%at low porosity and 22%-48.66%and 27.77%-51.57%at high porosity,respectively as compared to the un-grouted samples.However,the strength of the grouted samples is decreased by 66.94%-75.47%and 77.17%-81.05%at lower porosity,and 79.37%-82.86%and 81.29%-95.55%at higher porosity for cement and for SCB grouts with an increase in the heating temperature from 30℃ to 300℃,respectively.These observations could be due to the suppression of favourable crack initiation locations,i.e.flaw tips along the samples due to the filling of the crack by grouting and generation of thermal cracks with temperature.The mechanism of strength behaviour is elucidated in detail based on fracture propagation analysis and the anisotropic response of with or,without grouted samples.展开更多
BaTiO_(3) (BT)-based piezoceramics with large temperature-stable strains and low hysteresis are urgently needed for high-precision actuators because of increasing environmental problems. Here, tetragonal [001]c-textur...BaTiO_(3) (BT)-based piezoceramics with large temperature-stable strains and low hysteresis are urgently needed for high-precision actuators because of increasing environmental problems. Here, tetragonal [001]c-textured (Ba_(0.98)Ca_(0.02))(Ti_(0.96)Sn_(0.04))O_(3) (BCTS) ceramics with a texture degree (F_(001)) of ~98% were obtained via the templated grain growth (TGG) method. A large maximum unipolar strain (S_(max)) of ~0.24% with a low strain hysteresis (Hs) of ~3.8% and an optimized piezoelectric strain coefficient (d_(33)^(*)) of ~1124 pm·V^(−1) are simultaneously achieved in the textured BCTS ceramics. Moreover, the variation in the strain response is less than 20% from room temperature (RT) to 100℃ for the textured ceramics. The underlying mechanism for the optimized strain performance could be attributed to the synergetic effect of the polarization extension and a fine domain structure. This work provides new insight for achieving a balance of multiple strain properties (large strain, low hysteresis, and high-temperature stability) in BT-based ceramics, showing the widespread application prospects of lead-free ceramics in high-precision actuators.展开更多
基金supported by the National Science and Technology Major Project,China(No.2019-VI-0004-0118)the National Natural Science Foundation of China(No.51771152)the National Key R&D Program of China(No.2018YFB1106800)。
文摘Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed slightly.The dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)increased.With the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical<2111>-<1123>rare-earth(RE)textures.The alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening contributions.These results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.
基金supported from Science and Technology Development Program of Jilin Province(Nos.20240101128JC,20230402058GH)National Natural Science Foundation of China(No.52130101).
文摘Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported.Herein,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock method.Such a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode materials.Coupled with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°C.Based on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.
基金funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan(Grant No.AP19680589).
文摘Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines.
文摘This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.
基金partially supported by National Natural Science Foundation of China(52172250)Institute of Process Engineering(IPE)Project for Frontier Basic Research(QYJC-2023-06)。
文摘The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nitrogen-doped carbon fibers loaded with a ternary metal sulf-ide((Fe,Co,Ni)_(9)S_(8))for use as the sulfur host in Li-S batteries.This materi-al was prepared using transfer blot filter paper as the carbon precursor,thiourea as the source of nitrogen and sulfur,and FeCl_(3)·6H_(2)O,CoCl_(2)·6H_(2)O and NiCl_(2)·6H_(2)O as the metal ion sources.It was synthesized by an impreg-nation method followed by calcination.The nitrogen doping significantly in-creased the conductivity of the host,and the metal sulfides have excellent catalytic activities.Theoretical calculations,and adsorption and deposition experiments show that active sites on the surface of FCNS@NCFs selectively adsorb polysulfides,facilitate rapid adsorption and conversion,prevent cathode passivation and inhib-it the polysulfide shuttling.The FCNS@NCFs used as the sulfur host has excellent electrochemical properties.Its initial dis-charge capacity is 1639.0 mAh g^(−1) at 0.2 C and room temperature,and it remains a capacity of 1255.1 mAh g^(−1) after 100 cycles.At−20~C,it has an initial discharge capacity of 1578.5 mAh g^(−1) at 0.2 C,with a capacity of 867.5 mAh g^(−1) after 100 cycles.Its excellent performance at both ambient and low temperatures suggests a new way to produce high-performance low-temper-ature Li-S batteries.
文摘The use of solar energy is today widely recognized for the green transition but also for addressing societal challenges associated with the rise in global surface temperature. The design of a photovoltaic solar panel field may require an understanding of how solar radiation oscillates with other variables or factors since multiple interactions occur during its transfer within the atmosphere. In this study, three years of the incoming shortwave radiation (SWin) and air temperature (Tair) data acquired within the “Institut de Mathématiques et de Sciences Physiques” were analyzed using the continuous wavelet transform to extract the inherent variability of these signals. The underlying characteristics meaning the timescale of these variabilities as well as the lead-lag relationship between SWin and Tair were also examined. With the wavelet power spectrum, the highest variability was evidenced at the 2 - 8 band period for the SWin, coinciding almost with that of Tair. This suggests that these two signals are well interconnected at this temporal scale. The results obtained with the phase (∅xy) difference analysis, reveal that SWin leads Tair by ~ 23.5˚ on average when (0 ∅xy∅xyi.e., periods ≤ 32 days), Tair increases with an increasing SWin since the lags between these two signals range between 0.09 - 2.30 days. However, when looking at their interdependence at a larger temporal scale (> 32 days), Tair lags SWin. An increase in SWin might not directly imply an increase in Tair. Overall, these findings give insight into complex relationships across scales between the incoming shortwave radiation and air temperature in a tropical humid region of Bénin.
文摘The objective of this research is to investigate the effects of cosmic ray Forbush Decreases (FDs) exceeding 7% in magnitude, occurring between 1985 and 2016, on upper atmospheric pressure and temperature at Abha and Tabouk. Employing the super epoch analysis method, the study concentrated on altitudes of 5 km and 10 km, uncovering significant variations. Seasonal and synoptic-scale variations were considered and excluded when necessary across eight 9-day periods. Both locations showed considerable fluctuations in pressure and temperature before and after the events. At 5 km altitude (21 events), Abha experienced more pressure increases both before (9 vs. 7) and after (12 vs. 11) the events compared to Tabouk. For temperature, Abha recorded more increases before the events (5 vs. 1), while Tabouk showed more decreases (19 vs. 15). Post-event, Tabouk had more temperature increases (13 vs. 10). At 10 km altitude (20 events), both regions experienced more decreases than increases in pressure and temperature before the events and more increases afterward. Notably, Abha experienced more pressure increases both 4 days before (9 vs. 7) and after the events (12 vs. 11) than Tabouk. For temperature, Abha recorded more increases before the events (5 vs. 1), while Tabouk showed more decreases (19 vs. 15). Post-event, Tabouk had more temperature increases (13 vs. 10). These findings underscore both similarities and differences in atmospheric responses to FDs between Abha and Tabouk. Both locations exhibited cooling trends before and warming trends after the events, with Tabouk demonstrating a more pronounced warming trend post-event. These results enhance our understanding of the atmospheric dynamics linked to FDs and assist in predicting weather patterns associated with these phenomena.
文摘Developing reliable adaptation and mitigation strategies to combat climate change is necessary at regional and local scales. The present study analyses the ability of the multi-model ensemble (MME) composed of fourteen (14) CORDEX-Africa simulations to capture characteristics of the mean temperature for the present day (1979-2005) and associated extremes over Côte d’Ivoire. For this end, the analysis uses the mean variables of the temperature (i.e., minimum temperature (TMIN), mean temperature (TMEAN) and maximum temperature (TMAX)) as well as associated extremes such as intra-period extreme temperature range (ETR), warm spell duration index (HWFI) and warm days index (TX90P) during January-February-March (JFM), April-May-June (AMJ), July-August-September (JAS) and October-November-December (OND) seasons. The results indicate that mean temperature variables (TMIN, TMEAN and TMAX) are underestimated by CORDEX MME in general, except TMEAN in the centre of Côte d’Ivoire. On the other hand, extreme temperature indices are overestimated over Côte d’Ivoire, except ETR in JAS with an underestimation of about 2˚C and TX90P during JAS in the southern part of the country in JFM, AMJ and OND with an underestimation varying between 1% to 4%. In addition, CORDEX MME and observational datasets (CPC and NCEP) have a significant correlation in simulating temperature variables (TMIN, TMEAN, TMIN), while this correlation is not significant in general for extreme temperature, except ETR and HWFI. Furthermore, extreme temperatures (TX90P and HWFI) are characterized by more important interannual variability in the observations CPC and NCEP for ETR. Moreover, mean temperature variables (TMIN, TMEAN, TMAX) show slight interannual variability with respect to the observations CPC and NCEP, which are characterized by the most variability. Overall, CORDEX MME outperforms the seasonal and spatial variability of the temperature and associated extremes over Côte d’Ivoire, although some biases in representing their magnitudes. Thus, the results of the present study will help take appropriate adaptation and mitigation strategies against heatwaves and extreme temperature advent over Côte d’Ivoire as these climate extremes are projected to increase over the country.
基金financially supported by the National Natural Science Foundation of China(Nos.51871148,51821001)。
文摘The influence of pouring temperature and mold temperature on the fluidity and hot tearing behavior of Al-2Li-2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloys was investigated by experimental investigation and simulation assessment.The results showed that the length of the spiral fluidity sample increases from 302 to 756 mm as the pouring temperature increases from 680 to 740℃,and from 293 to 736 mm as the mold temperature increases from 200 to 400℃.The hot tearing susceptibility(HTS)firstly decreases and then increases with increasing pouring and mold temperatures,which is mainly caused by the oxide inclusion originating from the high activity of Li at excessive pouring temperature.Excessive pouring and mold temperatures easily produce oxide inclusions and holes,leading to a reduction in fluidity and an increase in HTS of the alloy.Combining the experimental and simulation results,the optimized pouring and mold temperatures are~720℃ and~300℃ for the cast Al-Li alloy,respectively.
文摘This study investigates the compressive and tensile properties of basalt fiber-reinforced concrete (BFRC) after ultra-low-temperature freeze-thaw cycles. Scanning electron microscope (SEM) analysis was conducted to examine the deterioration mechanisms caused by freeze-thaw cycles and sulfate erosion. The results show that compressive and tensile strengths increase with basalt fiber dosage. The optimal dosage is 0.2%. With longer exposure to sulfate erosion, both strengths decline significantly. Basalt fibers effectively bridge cracks, control expansion, enhance compactness, and improve concrete performance. Ultra-low-temperature freeze-thaw cycles and sulfate erosion cause rapid crack growth. Sulfate erosion produces crystallization products and expansive substances. These fill cracks, create pressure, and damage the internal structure. Freezing and expansion forces further enlarge voids and cracks. This provides space for expansive substances, worsening concrete deterioration and reducing its performance.
基金funded by the National Natural Science Foundation of China(62304023)partially funded by the National Key R&D Program of China(2023YFB3507300)+1 种基金Natural Science Foundation of Chongqing(2022NSCQ-MSX5423)Beijing Institute of Technology Research Fund Program for Young Scholars(XSQD-202206004).
文摘In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining method coupled with a temperature compensation strategy.To improve performance,a T-type device with a 1μm gap was fabricated resulting in an average sensitivity of 1.10 V/lgPa,which was 2.89 times larger than that(0.38 V/lgPa)of a L-type device with a 100μm gap.Additionally,FEA simulations were conducted,analyzing the influence of heater temperature on sensitivity and the attenuation of sensitivity across varying ambient temperatures.A semi-empirical theoretical mode was derived for performance prediction,demonstrating strong alignment with experimental results,underscoring its effectiveness in compensating for sensitivity attenuation.Building on the foundation,the device’s performance under different ambient temperatures was characterized and effectively compensated in two distinct operational modes:constant temperature mode and constant temperature difference mode(the whole range temperature compensation error can be controlled within 2.5%).Finally,the short-time stability(variation level is approximately 1 mV),noise floor(Vrms=384μV)and detection limit(0.07 Pa@1 Hz)of the device were characterized,confirming its suitability for practical implementation.
基金jointly supported by the National Key Research and Development Program of China(2022YFC3104304)the National Natural Science Foundation of China(Grant No.41876011)+1 种基金the 2022 Research Program of Sanya Yazhou Bay Science and Technology City(SKJC-2022-01-001)the Hainan Province Science and Technology Special Fund(ZDYF2021SHFZ265)。
文摘Three-dimensional ocean subsurface temperature and salinity structures(OST/OSS)in the South China Sea(SCS)play crucial roles in oceanic climate research and disaster mitigation.Traditionally,real-time OST and OSS are mainly obtained through in-situ ocean observations and simulation by ocean circulation models,which are usually challenging and costly.Recently,dynamical,statistical,or machine learning models have been proposed to invert the OST/OSS from sea surface information;however,these models mainly focused on the inversion of monthly OST and OSS.To address this issue,we apply clustering algorithms and employ a stacking strategy to ensemble three models(XGBoost,Random Forest,and LightGBM)to invert the real-time OST/OSS based on satellite-derived data and the Argo dataset.Subsequently,a fusion of temperature and salinity is employed to reconstruct OST and OSS.In the validation dataset,the depth-averaged Correlation(Corr)of the estimated OST(OSS)is 0.919(0.83),and the average Root-Mean-Square Error(RMSE)is0.639°C(0.087 psu),with a depth-averaged coefficient of determination(R~2)of 0.84(0.68).Notably,at the thermocline where the base models exhibit their maximum error,the stacking-based fusion model exhibited significant performance enhancement,with a maximum enhancement in OST and OSS inversion exceeding 10%.We further found that the estimated OST and OSS exhibit good agreement with the HYbrid Coordinate Ocean Model(HYCOM)data and BOA_Argo dataset during the passage of a mesoscale eddy.This study shows that the proposed model can effectively invert the real-time OST and OSS,potentially enhancing the understanding of multi-scale oceanic processes in the SCS.
基金supported by National Key Research and Development Program of China(Grant No.2024YFA1210500)National Natural Science Foundation of China(Grant Nos.U2341225 and 62375242)+1 种基金Sichuan Science and Technology Program(2025YFHZ0297)Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240647).
文摘High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)band—along with microwave stealth and efficient thermal management at high temperatures,remains a significant challenge.Here,we propose a strategy that integrates an IR-selective emitter(Mo/Si multilayer films)and a microwave metasurface(TiB2–Al2O3–TiB2)to enable multi-infrared band stealth,encompassing mid-wave infrared(MWIR),long-wave infrared(LWIR),and SWIR bands,and microwave(X-band)stealth at 700℃,with simultaneous radiative cooling in non-atmospheric window(5–8μm).At 700℃,the device exhibits low emissivity of 0.38/0.44/0.60 in the MWIR/LWIR/SWIR bands,reflection loss below−3 dB in the X-band(9.6–12 GHz),and high emissivity of 0.82 in 5–8μm range—corresponding to a cooling power of 9.57 kW m^(−2).Moreover,under an input power of 17.3 kW m^(−2)—equivalent to the aerodynamic heating at Mach 2.2—the device demonstrates a temperature reduction of 72.4℃ compared to a conventional low-emissivity molybdenum surface at high temperatures.This work provides comprehensive guidance on high-temperature stealth design,with far-reaching implications for multispectral information processing and thermal management in extreme high-temperature environments.
基金granted by the National Natural Science Foundation of China(Nos.22171264 and 22301301)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB1170000)the Self-Deployment Project Research Program of Haixi Institutes,Chinese Academy of sciences(No.CXZX-2022-GH02).
文摘Luminescent materials with tunable emission wavelengths/colors hold great potential for smart response devices,data security,sensors,and so on.However,development of stimuli-responsive luminescent materials with traditional organic or inorganic luminophores remains challenging due to their lack of tunability.Herein,we report the tunable luminescence and ratiometric temperature sensing applications with a europium-organic cage(Eu4L4)featuring concentration-dependent hierarchical self-assembly behavior.Notably,white light emission was achieved by adjusting the equilibrium ratio between the red-emissive cage monomer and cyan-emissive cage aggregate.Taking advantage of the dual emissive nature of the system,ratiometric luminescent temperature sensing has also been achieved,exhibiting a sensitivity of 2.04% and linear correlation coefficient of 0.997 from 250 to 320 K.
基金This study was financed in part by the Coordenacao de Aperfeiçoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001the Brazilian Conselho Nacional de Pesquisa-CNPq(study and research grants and research funding-Process 303666/2018-8,408162/2018-0,441335/2020-9,302969/2021-7,and 50484/2022-4)Fundacao de ApoioaPesquisa do Estado de Minas Gerais-FAPEMIG(study grants and research funding-Process CRA/APQ 0100-18,APQ-03364-21 and CAG/PPM 00568-16).
文摘Tropical mountain peatlands in Brazil’s Southern Espinhaço Range are vital ecosystems,acting as carbon reservoirs,hydrological buffers,and biodiversity hotspots while sustaining traditional livelihoods and preserving paleoenvironmental records.Despite their importance,peatlands outside protected areas face degradation by grazing and fires,threatening their ability to regulate ecosystem processes sensitive to temperature,such as greenhouse gas emissions,water cycling,biological activity,and organic matter decomposition.Since 2016,we have monitored peat temperatures in two contrasting peatlands–one preserved(within a protected area)and one disturbed(outside the protected area)–to understand how anthropogenic disturbances and climate variability impact these fragile ecosystems.Seasonal patterns dominated temperature variation,accounting for 60% of air and 81%–92% of peatland temperature variation.However,average temperatures and amplitudes differed between peatlands and depths.Interannual variability revealed stronger trends in the disturbed peatland,where a 1℃ increase in air temperature caused the trend to increase 0.70℃–0.87℃ on average at depths of 0.85 m–0.92 m.By contrast,the preserved peatland showed smaller increases(0.20℃–0.24℃)at comparable depths(1.06 m–1.24 m),suggesting a greater resilience.Temperature variation in the monitored peatlands was majorly driven by seasonal patterns,as revealed by time series decomposition and sinewave fit.Average temperature and amplitude varied between the two peatlands and among sampling sites,reflecting differences in environmental conditions and measurement depth.Interannual variability also exhibited distinct effects between peatlands and monitoring sites.The time series trend component showed more pronounced fluctuations at shallower depths and in the disturbed peatland.For every 1℃ increase in the trend component of the air temperature,the trend component of the peatland time series increased by 0.70℃ and 0.87℃on average at depths of 0.85 m and 0.92 m,respectively,in the disturbed peatland.In contrast,the preserved peatland exhibited smaller increases of 0.20℃ and 0.24℃ at comparable depths(1.06 m and 1.24 m).These findings highlight the potential for feedback responses between peatland disturbance and climate change,threatening their critical role in regulating carbon and water cycles.Expanding long-term monitoring,strengthening conservation efforts,and raising public awareness are essential to safeguard the ecosystem services provided by tropical mountain peatlands.
基金supported by the Key Research and Development Plan of Anhui Province(Grant No.202104a05020059)Excellent Scientific Research and Innovation Team of Anhui Province(Grant No.2022AH010003).
文摘In this paper,a dual Mach-Zehnder interferometer for measuring both temperature and strain is proposed and verified by experiments.The sensor configuration involves cascading a four-core fiber and a double-clad fiber between two single-mode fibers.By exploiting the different responses of the two Mach-Zehnder interferometers to temperature and strain,we construct a matrix using two selected resonance dips from the transmission spectra,so that both temperature and strain can be measured simultaneously.The experimental results show the sensor’s remarkable performance,with the maximum temperature sensitivity of-94.2 pm/℃and the maximum strain sensitivity of 2.68 pm/με.The maximum temperature error and strain error are found to be±0.35℃and±4.8με,respectively.Compared with other optical fiber sensors,the sensor has high sensitivity,a simple structure,and ease to manufacture and implement,making it a structure choice for applications in quality inspection of materials.
文摘Leaf cutting ants of the genus Atta cultivate fungal gardens,carefully modifying environmental conditions to maintain optimal temperature for fungal growth.Antennal nerves from Atta are highly temperature sensitive,but the underlying molecular sensor is unknown.Here,we utilize Atta texana(Texas leaf cutter ant)to investigate the molecular basis of ant temperature sensation and how it might have evolved as the range expanded northeast across Texas from ancestral populations in Mexico.We focus on transient receptor potential(TRP)channel genes,the best characterized temperature sensor proteins in animals.Atta texana antennae express 6 of 13 Hymenopteran TRP channel genes and sequences are under a mix of relaxed and intensified selection.In a behavioral assay,we find A.texana workers prefer 24℃(range 21−26℃)for fungal growth.There was no evidence of regulatory evolution across a temperature transect in Texas,but instead Hymenoptera-specific TRPA(HsTRPA)expression highly correlated with ambient temperature.When expressed in vitro,HsTRPA from A.texana is temperature activated with Q10 values exceeding 100 on initial exposure to temperatures above 33℃.Surprisingly,HsTRPA also appears to be activated by cooling,and therefore to our knowledge,the first non-TRPA1 ortholog to be described with dual heat/cold activation and the first in any invertebrate.
基金supported by the National Natural Science Foundation of China(NSFC)(62422501)Beijing Nova Program(20230484254,20240484742)Hebei Natural Science Foundation(F2024105039).
文摘Implantable temperature sensors are revolutionizing physiological monitoring and playing a crucial role in diagnostics,therapeutics,and life sciences research.This review classifies the materials used in these sensors into three categories:metal-based,inorganic semiconductor,and organic semiconductor materials.Metal-based materials are widely used in medical and industrial applications due to their linearity,stability,and reliability.Inorganic semiconductors provide rapid response times and high miniaturization potential,making them promising for biomedical and environmental monitoring.Organic semiconductors offer high sensitivity and ease of processing,enabling the development of flexible and stretchable sensors.This review analyzes recent studies for each material type,covering design principles,performance characteristics,and applications,highlighting key advantages and challenges regarding miniaturization,sensitivity,response time,and biocompatibility.Furthermore,critical performance parameters of implantable temperature sensors based on different material types are summarized,providing valuable references for future sensor design and optimization.The future development of implantable temperature sensors is discussed,focusing on improving biocompatibility,long-term stability,and multifunctional integration.These advancements are expected to expand the application potential of implantable sensors in telemedicine and dynamic physiological monitoring.
文摘This study investigates the effect of different in situ conditions like flaw infill,heat-treatment temperatures,and sample porosities on the anisotropic compressive response of jointed samples with an impersistent flaw.Jointed samples of different porosities are prepared by mixing Plaster of Paris(POP)with different water contents,i.e.60%(i.e.for lower porosity)and 80%(i.e.for higher porosity).These samples are grouted with different infill materials,i.e.un-grouted,cement and sand-cement(3:1)-bio-concrete(SCB)mix and subsequently subjected to different temperatures,i.e.100℃,200℃ and 300℃.The results reveal the distinct stages in the stress-strain responses of samples characterized by initial micro-cracks closure,elastic transition,and non-linear response till peak followed by a post-peak behaviour.The un-grouted samples exhibit their lowest strength at 30°joint orientation.The ratios of maximum to minimum strength are 3.11 and 3.22 with varying joint orientations for lower and higher porosity samples,respectively.Strengths of cement and SCB mix grouted samples are increased for all joint orientations ranging between 16.13%-69.83%and 18.04%-73%at low porosity and 22%-48.66%and 27.77%-51.57%at high porosity,respectively as compared to the un-grouted samples.However,the strength of the grouted samples is decreased by 66.94%-75.47%and 77.17%-81.05%at lower porosity,and 79.37%-82.86%and 81.29%-95.55%at higher porosity for cement and for SCB grouts with an increase in the heating temperature from 30℃ to 300℃,respectively.These observations could be due to the suppression of favourable crack initiation locations,i.e.flaw tips along the samples due to the filling of the crack by grouting and generation of thermal cracks with temperature.The mechanism of strength behaviour is elucidated in detail based on fracture propagation analysis and the anisotropic response of with or,without grouted samples.
基金supported by the National Natural Science Foundation of China(No.52102132)the Natural Science Foundation of Shandong Province of China(Nos.ZR2024ME201 and ZR2021ME085)+1 种基金the Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices(No.EFMD2023001M)the Natural Science Foundation of Heilongjiang Province(No.LH2022E049).
文摘BaTiO_(3) (BT)-based piezoceramics with large temperature-stable strains and low hysteresis are urgently needed for high-precision actuators because of increasing environmental problems. Here, tetragonal [001]c-textured (Ba_(0.98)Ca_(0.02))(Ti_(0.96)Sn_(0.04))O_(3) (BCTS) ceramics with a texture degree (F_(001)) of ~98% were obtained via the templated grain growth (TGG) method. A large maximum unipolar strain (S_(max)) of ~0.24% with a low strain hysteresis (Hs) of ~3.8% and an optimized piezoelectric strain coefficient (d_(33)^(*)) of ~1124 pm·V^(−1) are simultaneously achieved in the textured BCTS ceramics. Moreover, the variation in the strain response is less than 20% from room temperature (RT) to 100℃ for the textured ceramics. The underlying mechanism for the optimized strain performance could be attributed to the synergetic effect of the polarization extension and a fine domain structure. This work provides new insight for achieving a balance of multiple strain properties (large strain, low hysteresis, and high-temperature stability) in BT-based ceramics, showing the widespread application prospects of lead-free ceramics in high-precision actuators.
