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
The inversion of ocean subsurface temperature and salinity(TS)is a hot topic and challenging problem in the oceanic sciences.In this study,a new method for the inversion of underwater TS in the South China Sea is prop...The inversion of ocean subsurface temperature and salinity(TS)is a hot topic and challenging problem in the oceanic sciences.In this study,a new method for the inversion of underwater TS in the South China Sea is proposed based on an improved generative adversarial network(GAN).The proposed model can derive the underwater TS from sea surface data(specifically,sea surface temperature and the sea surface height anomalies)with an eddy-resolving horizontal resolution of(1/12)°.For comparison,a robust statistics-based model,the Modular Ocean Data Assimilation System(MODAS),is also used to invert the subsurface TS in this study.Results show that the root-mean-square errors(RMSEs)of the TS inversions from the GAN-based model are significantly smaller than those from MODAS,especially in the thermocline of the South China Sea,where the RMSE of temperature can be reduced by up to 21.7%and the subsurface salinity RMSE is smaller than 0.32.In particular,the inversion results obtained using the proposed model are more accurate in either the seasonalscale or the synoptic-scale analysis.Firstly,the GAN-based model is more effective for the seasonal-scale extraction and diagnosis of the subsurface stratification,especially in the Luzon Strait and coastal shelf sea areas,in which stronger nonlinearities arise from the Kuroshio intrusion or complex coastal processes dominate the ocean subsurface dynamics.Secondly,the vertical heat pump and cold suction effects in the ocean's upper layers induced by the passage of a typhoon can be reflected more reasonably based on the synoptic-scale analysis with the proposed model.Furthermore,the underwater 3D structure of mesoscale eddies can be skillfully captured by AIGAN(Attention and Inception GAN),which can extract more refined eddy patterns with stronger recognition capability compared with the statistics-based MODAS.The present study can be extended to further explore the subsurface characteristics of the internal variability in the South China Sea.展开更多
High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant a...High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant and salt-resistant foaming agents is commonly used to control gas channeling.The feasibility of the compound system of dodecyl hydroxyl sulfobetaine(HSB12)andα-olefin sulfonate(AOS)as foaming agent for sandstone reservoir was studied at 130℃and 22×10^(4)mg/L.The results showed that the foaming agent(HSB12 and AOS were compounded in a 6:1 mass ratio,in this article,this foaming agent is simply referred to as SA61)had good solubility in 22×10^(4)mg/L simulated formation water.Besides,the foaming volume of SA61 and HSB12 was similar,but the foam decay half-life of SA61was 10-25 times higher than that of HSB12.The foaming performance of SA61 on the surface of quartz sand remained above 90%of that before adsorption.The strong interaction between HSB12 and AOS in the compound system SA61 was demonstrated by surface rheological measurements and NMR studies of surfactants.The results of co re flow test showed that SA61 had better mobility control ability than HSB12under the same surfactant concentration.In addition,SA61 showed a selective mobility reduction in2005.30 and 632.00 mD cores.The above research results can guide the selection and application of foaming agent in clastic reservoir.展开更多
In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experi...In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experiment were conducted to explore the effects of moisture content,confining pressure,and temperature on the stress-strain characteristics and failure modes of frozen soil,as well as the changes in the internal microstructure of the sample.The experimental results show that the strength of frozen sulfate saline soil first increases and then decreases with the increase of moisture content,and the maximum strength corresponds to a moisture content of 15%.The changes in confining pressure and strength have the same trend.The lower the temperature,the greater the strength of the sample.During the entire loading process,the specimens undergo a gradual transition from volume shrinkage to volume expansion.Due to the strain harden behavior of the stress-strain curve throughout the entire loading process,the failure mode of the specimens is plastic failure.The internal microstructure of the sample gradually transitions from point-point contact and edge-point contact before shearing to edge-surface contact and edge-edge contact after shearing,and the pore size inside the sample increases after shearing,with a loose arrangement of the particle skeleton.The above research conclusions can lay a certain theoretical foun-dation for the engineering design and construction of sulfate saline soil in cold and arid areas.展开更多
A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying sc...A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying scenarios including nitrogen fertilization rates,irrigation rates,and air temperatures in the Hetao Irrigation District(HID)over the 38-year period.DAYCENT model was used to predict carbon dioxide(CO_(2))fluxes from cultivated soils in the HID,Inner Mongolia from^(2)023 to 2060(the year of achieving the"carbon neutrality"goal)in this study.Results showed that mean soil CO_(2)fluxes in the sunflower field[1035.13 g/(m^(2).yr)]were significantly lower than those in the maize field[1405.54 g/(m^(2).yr)].An increase in nitrogen fertilization rate led to a significant escalation in soil CO_(2)fluxes.Moreover,elevating irrigation rates for washing salts by irrigation(WSBI)diminished soil CO_(2)fluxes in the sunflower field while amplifying them in the maize field.A rise in air temperature resulted in an increase in soil CO_(2)fluxes from the maize field,with annual increases observed,but a reduction in soil CO_(2)fluxes from the sunflower field.The sunflower fields in the HID have a more substantial advantage than the corn fields in mitigating soil CO_(2)emissions.展开更多
We propose an in-fiber Michelson-Fabry-Perrot(M-FP)hybrid interferometer for the simultaneous measurement of seawater temperature and salinity.The sensor head consists of two parallel hetero Fabry-Perot(FP)cavities fa...We propose an in-fiber Michelson-Fabry-Perrot(M-FP)hybrid interferometer for the simultaneous measurement of seawater temperature and salinity.The sensor head consists of two parallel hetero Fabry-Perot(FP)cavities fabricated on the end face of the twin core fiber(TCF).A fiber fusion taper is used to split and recouple the light in the two cores.In this case,the Vernier effect can be obtained which can greatly enhance the sensitivity and solve the problem of temperature cross-sensitivity.Different from the traditional demodulation method based on envelop detection,we employed frequency domain decomposition method(FDDM)to demodulate the sensing signal.The simulation results indicate that the proposed sensor has high sensitivity to salinity and temperature.Thanks to the merits of high sensitivity,ease of fabrication and small footprint,the proposed seawater temperature and salinity sensor would have potential applications in marine science,food industry and ocean ranching.展开更多
A novel temperature and salinity discriminative sensing method based on forward Brillouin scattering(FBS)in 1060-XP single-mode fiber(SMF)is proposed.The measured frequency shifts corresponding to different radial aco...A novel temperature and salinity discriminative sensing method based on forward Brillouin scattering(FBS)in 1060-XP single-mode fiber(SMF)is proposed.The measured frequency shifts corresponding to different radial acoustic modes in 1060-XP SMF show different sensitivities to temperature and salinity.Based on the new phenomenon that different radial acoustic modes have different frequency shift-temperature and frequency shift-salinity coefficients,we propose a novel method for simultaneously measuring temperature and salinity by measuring the frequency shift changes of two FBS scattering peaks.In a proof-of-concept experiment,the temperature and salinity measurement errors are 0.12℃and 0.29%,respectively.The proposed method for simultaneously measuring temperature and salinity has the potential applications such as ocean surveying,food manufacturing and pharmaceutical engineering.展开更多
The formation mechanism of high salinity geothermal water is significant for utilizing geothermal resources and mineral resources.The high salinity in geothermal water may be derived from the geothermal mother fluid o...The formation mechanism of high salinity geothermal water is significant for utilizing geothermal resources and mineral resources.The high salinity in geothermal water may be derived from the geothermal mother fluid or from the evaporite dissolution.It is difficult to distinguish between these two sources because they may have similar hydrochemistry.In this paper,water chemistry and stable isotopes were used to explore the high salinity geothermal water in Yanchanghe geothermal field,central China.It is a lowtemperature hydrothermal system in the inland karst area.The thermal water is Cl-Na type with high salinity(TDS>8,400 mg/L).The modified silicon thermometer is more suitable and the reasonable result is about 58.8℃.The maximum circulation depth is 1.9 km.Using the temperature of hot and cold water to estimate the mixing ratio is 58%-81%.Saturation index(SI),Na/1000-K/100-Mg1/2 and Gibbs diagram suggest that the main source of salt in geothermal water is derived from the evaporite dissolution,which provides Cl-of 11,264-31,279 mg/L and Na+of 9,272-21,236 mg/L.We found the combination of temperature and hydrogeochemistry can be used to investigate the formation mechanism and mixing process of high-salinity geothermal water formed in a karst low-temperature hydrothermal system.展开更多
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
Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural applications.The emerging face-centered cubic medium-entropy alloys(MEAs)demonstra...Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural applications.The emerging face-centered cubic medium-entropy alloys(MEAs)demonstrate outstanding mechanical properties at both ambient and cryogenic temperatures.They are anticipated to extend their applicability to elevated temperatures,owing to their inherent advantages in leveraging multiple strengthening and deformation mechanisms.Here,a dual heterostructure,comprising of heterogeneous grain structure with heterogeneous distribution of the micro-scale Nb-rich Laves phases,is introduced in a CrCoNi-based MEA through thermo-mechanical processing.Additionally,a high-density nano-coherentγ’phase is introduced within the grains through isothermal aging treatments.The superior thermal stability of the heterogeneously distributed precipitates enables the dual heterostructure to persist at temperatures up to 1073 K,allowing the MEA to maintain excellent mechanical properties across a wide temperature range.The yield strength of the dual-heterogeneous-structured MEA reaches up to 1.2 GPa,1.1 GPa,0.8 GPa,and 0.6 GPa,coupled with total elongation values of 28.6%,28.4%,12.6%,and 6.1%at 93 K,298 K,873 K,and 1073 K,respectively.The high yield strength primar-ily stems from precipitation strengthening and hetero-deformation-induced strengthening.The high flow stress and low stacking fault energy of the dual-heterogeneous-structured MEA promote the formation of high-density stacking faults and nanotwins during deformation from 93 K to 1073 K,and their density increase with decreasing deformation temperature.This greatly contributes to the enhanced strainhardening capability and ductility across a wide temperature range.This study offers a practical solution for designing dual-heterogeneous-structured MEAs with both high yield strength and large ductility across a wide temperature range.展开更多
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa...High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.展开更多
In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increas...In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increase in salinity resulted in a decrease in particle size of the granular sludge,which was concentrated in the range of 0.5-1.0 mm.The content of EPS(extracellular polymeric substances)in the granular sludge gradually increased with increasing salinity and the addition of betaine(a typical compatible solute).Meanwhile,the microbial community structure was significantly affected by salinity,with high salinity reducing the diversity of bacteria.At higher salinity,Patescibacteria and Proteobacteria gradually became the dominant phylum,with relative abundance increasing to 13.53%and 12.16%at 20 g/L salinity.Desulfobacterota and its subordinate Desulfovibrio,which secrete EPS in large quantities,dominated significantly after betaine addition.Their relative abundance reached 13.65%and 7.86%at phylum level and genus level.The effect of these changes on the treated effluent was shown as the average chemical oxygen demand(COD)removal rate decreased from 82.10%to 79.71%,78.01%,68.51%and 64.55%when the salinity gradually increased from 2 g/L to 6,10,16 and 20 g/L.At the salinity of 20 g/L,average COD removal increased to 71.65%by the addition of 2 mmol/L betaine.The gradient elevated salinity and the exogenous addition of betaine played an important role in achieving stability of the anaerobic system in a highly saline environment,which provided a feasible strategy for anaerobic treatment of organic saline wastewater.展开更多
Two anaerobic ammonia oxidation(anammox)systems,one with adding nano-scale zerovalent iron modified biochar(nZVI@BC)and the other with adding biochar,were constructed to explore the feasibility of nZVI@BC for enhancin...Two anaerobic ammonia oxidation(anammox)systems,one with adding nano-scale zerovalent iron modified biochar(nZVI@BC)and the other with adding biochar,were constructed to explore the feasibility of nZVI@BC for enhancing the resistance of low-nitrogen anammox processes to low temperatures.The results showed that the average nitrogen removal efficiency with nZVI@BC addition at lowtemperatureswas maintained at about 80%,while that with biochar addition gradually decreased to 69.49%.The heme-c content of biomass with nZVI@BC was significantly higher by 36.60%-91.45%.Additional,nZVI@BC addition resulted in more extracellular polymeric substances,better biomass granulation,and a higher abundance of anammox bacteria.In particularly,anammox genes hzsA/B/C,hzo and hdh played a pivotal role in maintaining nitrogen removal performance at 15℃.These findings suggest that nZVI@BC has the potential to enhance the resistance of low-nitrogen anammox processes to low temperatures,making it a valuable approach for practical applications in low-nitrogen and low-temperature wastewater treatment.展开更多
Low temperature(LT)in spring has become one of the principal abiotic stresses that restrict the growth and development of wheat.Diverse analyses were performed to investigate the mechanism underlying the response of w...Low temperature(LT)in spring has become one of the principal abiotic stresses that restrict the growth and development of wheat.Diverse analyses were performed to investigate the mechanism underlying the response of wheat grain development to LT stress during booting.These included morphological observation,measurements of starch synthase activity,and determination of amylose and amylopectin content of wheat grain after exposure to treatment with LT during booting.Additionally,proteomic analysis was performed using tandem mass tags(TMT).Results showed that the plumpness of wheat grains decreased after LT stress.Moreover,the activities of sucrose synthase(SuS,EC 2.4.1.13)and ADP-glucose pyrophosphorylase(AGPase,EC 2.7.7.27)exhibited a significant reduction,leading to a significant reduction in the contents of amylose and amylopectin.A total of 509 differentially expressed proteins(DEPs)were identified by proteomics analysis.The Gene Ontology(GO)enrichment analysis showed that the protein difference multiple in the nutritional repository activity was the largest among the molecular functions,and the up-regulated seed storage protein(ssP)played an active role in the response of grains to LT stress and subsequent damage.The Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis showed that LT stress reduced the expression of DEPs such as sucrose phosphate synthase(SPS),glucose-1-phosphate adenylyltransferase(glgC),andβ-fructofuranosidase(FFase)in sucrose and starch metabolic pathways,thus affecting the synthesis of grain starch.In addition,many heat shock proteins(HsPs)were found in the protein processing in endoplasmic reticulum pathways,which can resist some damage caused by LT stress.These findings provide a new theoretical foundation for elucidating the underlying mechanism governing wheat yield developmentafterexposuretoLTstress inspring.展开更多
In the applications such as food production,the environmental temperature should be measured continuously dur-ing the entire process,which requires an ultra-low-power temperature sensor for long-termly monitoring.Conv...In the applications such as food production,the environmental temperature should be measured continuously dur-ing the entire process,which requires an ultra-low-power temperature sensor for long-termly monitoring.Conventional tempera-ture sensors trade the measurement accuracy with power consumption.In this work,we present a battery-free wireless tempera-ture sensing chip for long-termly monitoring during food production.A calibrated oscillator-based CMOS temperature sensor is proposed instead of the ADC-based power-hungry circuits in conventional works.In addition,the sensor chip can harvest the power transferred by a remote reader to eliminate the use of battery.Meanwhile,the system conducts wireless bidirectional communication between the sensor chip and reader.In this way,the temperature sensor can realize both a high precision and battery-free operation.The temperature sensing chip is fabricated in 55 nm CMOS process,and the reader chip is imple-mented in 65 nm CMOS technology.Experimental results show that the temperature measurement error achieves±1.6℃ from 25 to 50℃,with battery-free readout by a remote reader.展开更多
Lithium-ion batteries(LIBs)face significant limitations in low-temperature environments,with the slow interfacial de-solvation process and the hindered Li+transport through the interphase layer emerging as key obstacl...Lithium-ion batteries(LIBs)face significant limitations in low-temperature environments,with the slow interfacial de-solvation process and the hindered Li+transport through the interphase layer emerging as key obstacles beyond the issue of ionic conductivity.This investigation unveils a novel formulation that constructs an anion-rich solvation sheath within strong solvents,effectively addressing all three of these challenges to bolster low-temperature performance.The developed electrolyte,characterized by an enhanced concentration of contact ion pairs(CIPs)and aggregates(AGGs),facilitates the formation of an inorganic-rich interphase layer on the anode and cathode particles.This promotes de-solvation at low temperatures and stabilizes the electrode-electrolyte interphase.Full cells composed of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)and graphite,when equipped with this electrolyte,showcase remarkable cycle stability and capacity retention,with 93.3% retention after 500 cycles at room temperature(RT)and 95.5%after 120 cycles at -20℃.This study validates the utility of the anion-rich solvation sheath in strong solvents as a strategy for the development of low-temperature electrolytes.展开更多
Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and capro...Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and caprock under in-situ high-temperature and confine-ment conditions is of considerable importance. Compared to conventional mechanical experiments on rock samples after high-temperat-ure treatment, in-situ high-temperature experiments can more accurately characterize the behavior of rocks in practical engineering,thereby providing a more realistic reflection of their mechanical properties. In this study, an in-situ high-temperature triaxial compressiontesting machine is developed to conduct in-situ compression tests on sandstone at different temperatures(25, 200, 400, 500, and 650℃)and confining pressures(0, 10, and 20 MPa). Based on the experimental results, the temperature-dependent changes in compressivestrength, peak strain, elastic modulus, Poisson's ratio, cohesion, and internal friction angle are thoroughly analyzed and discussed. Resultsindicate that the mass of sandstone gradually decreases as the temperature increases. The thermal conductivity and thermal diffusivity ofsandstone exhibit a linear relationship with temperature. Peak stress decreases as the temperature rises, while it increases with higher con-fining pressures. Notably, the influence of confining pressure on peak stress diminishes at higher temperatures. Additionally, as the tem-perature rises, the Poisson's ratio of sandstone decreases. The internal friction angle also decreases with increasing temperature, with 400℃ acting as the threshold temperature. Interestingly, under uniaxial conditions, the damage stress of sandstone is less affected by tem-perature. However, when the confining pressure is 10 or 20 MPa, the damage stress decreases as the temperature increases. This study en-hances our understanding of the influence of in-situ high-temperature and confinement conditions on the mechanical properties of sand-stone strata. The study also provides valuable references and experimental data that support the development of low-to medium-maturityoil shale resources.展开更多
The impact of extreme temperatures on the health of individuals in different organizations remains uncertain.We employed stratified analyses to examine the impacts of summer(April-September)daily maximum temperatures ...The impact of extreme temperatures on the health of individuals in different organizations remains uncertain.We employed stratified analyses to examine the impacts of summer(April-September)daily maximum temperatures and winter(October-March)daily minimum temperatures on blood pressure and lipid profiles across government staff,com-pany employees,and researchers.We examined 209,477 physical examination records from a physical examination center in the First Affiliated Hospital of USTC from 2017 to 2021.Employing a segmented regression model within the frame-work of generalized linear regression(GLM),we examined the causal impact of extreme temperatures on health outcomes.Additionally,sensitivity analyses were conducted via distributed lag nonlinear models(DLNMs),with a focus on ob-serving the long-term effects over a period of 21 days.Our findings indicate that government staff face increased health risks during extremely low temperatures,regardless of the season.Compared with participants experiencing median tem-peratures,government staff exposed to extremely low temperatures(below the 10th percentile,below 24℃)in the sum-mer presented maximum increases of 2.32 mmHg(95%CI:1.542-3.098)in diastolic blood pressure and 6.481 mmHg(95%CI:5.368-7.594)in systolic blood pressure.In winter,government staff exposed to temperatures below the 10th per-centile(below 1℃)demonstrated maximum increases of 0.278 mmol/L(95%CI:0.210-0.346)in total cholesterol,0.153 mmol/L(95%CI:0.032-0.274)in triglycerides,and 0.077 mmol/L(95%CI:0.192-0.134)in low-density lipoprotein.Conversely,warm winters benefit company employees,whereas researchers exhibit lower sensitivity to temperature changes in winter.The maximum temperatures in summer and minimum temperatures in winter had greater impacts on in-dividuals.Small temperature fluctuations impact health more than large changes do.Notably,both the maximum and min-imum temperatures were better predictors of health outcomes than the daily average temperature was.Blood pressure con-sistently displayed significant associations with temperature across all three groups,with extremely low temperatures in-creasing the risk and extremely high temperatures reducing it.However,the relationship between temperature and blood lipids is complex.展开更多
The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design c...The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design concept of eutectic electrolyte is presented by mixing long chain polymer molecules,polyethylene glycol dimethyl ether(PEGDME),with H_(2)O based on zinc trifluoromethyl sulfonate(Zn(OTf)2),to reconstruct the Zn^(2+)solvated structure and in situ modified the adsorption layer on Zn electrode surface.Molecular dynamics simulations(MD),density functional theory(DFT)calculations were combined with experiment to prove that the long-chain polymer-PEGDME could effectively reduce side reactions,change the solvation structure of the electrolyte and priority absorbed on Zn(002),achieving a stable dendrite-free Zn anode.Due to the comprehensive regulation of solvation structure and zinc deposition by PEGDME,it can stably cycle for over 3200 h at room temperature at 0.5 mA/cm^(2)and 0.5 mAh/cm^(2).Even at high-temperature environments of 60℃,it can steadily work for more than 800 cycles(1600 h).Improved cyclic stability and rate performance of aqueous Zn‖VO_(2)batteries in modified electrolyte were also achieved at both room and high temperatures.Beyond that,the demonstration of stable and high-capacity Zn‖VO_(2)pouch cells also implies its practical application.展开更多
The roughness of the fracture surface directly affects the strength,deformation,and permeability of the surrounding rock in deep underground engineering.Understanding the effect of high temperature and thermal cycle o...The roughness of the fracture surface directly affects the strength,deformation,and permeability of the surrounding rock in deep underground engineering.Understanding the effect of high temperature and thermal cycle on the fracture surface roughness plays an important role in estimating the damage degree and stability of deep rock mass.In this paper,the variations of fracture surface roughness of granite after different heating and thermal cycles were investigated using the joint roughness coefficient method(JRC),three-dimensional(3D)roughness parameters,and fractal dimension(D),and the mechanism of damage and deterioration of granite were revealed.The experimental results show an increase in the roughness of the granite fracture surface as temperature and cycle number were incremented.The variations of JRC,height parameter,inclination parameter and area parameter with the temperature conformed to the Boltzmann's functional distribution,while the D decreased linearly as the temperature increased.Besides,the anisotropy index(Ip)of the granite fracture surface increased as the temperature increased,and the larger parameter values of roughness characterization at different temperatures were attained mainly in directions of 20°–40°,60°–100°and 140°–160°.The fracture aperture of granite after fracture followed the Gauss distribution and the average aperture increased with increasing temperature,which increased from 0.665 mm at 25℃to 1.058 mm at 800℃.High temperature caused an uneven thermal expansion,water evaporation,and oxidation of minerals within the granite,which promoted the growth and expansion of microfractures,and reduced interparticle bonding strength.In particular,the damage was exacerbated by the expansion and cracking of the quartz phase transition after T>500℃.Thermal cycles contributed to the accumulation of this damage and further weakened the interparticle bonding forces,resulting in a significant increase in the roughness,anisotropy,and aperture of the fracture surface after five cycles.展开更多
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 the National Research and Development Program of China(Grant No.2021YFC2803003)the National Natural Science Foundation of China(Grant No.42375143)。
文摘The inversion of ocean subsurface temperature and salinity(TS)is a hot topic and challenging problem in the oceanic sciences.In this study,a new method for the inversion of underwater TS in the South China Sea is proposed based on an improved generative adversarial network(GAN).The proposed model can derive the underwater TS from sea surface data(specifically,sea surface temperature and the sea surface height anomalies)with an eddy-resolving horizontal resolution of(1/12)°.For comparison,a robust statistics-based model,the Modular Ocean Data Assimilation System(MODAS),is also used to invert the subsurface TS in this study.Results show that the root-mean-square errors(RMSEs)of the TS inversions from the GAN-based model are significantly smaller than those from MODAS,especially in the thermocline of the South China Sea,where the RMSE of temperature can be reduced by up to 21.7%and the subsurface salinity RMSE is smaller than 0.32.In particular,the inversion results obtained using the proposed model are more accurate in either the seasonalscale or the synoptic-scale analysis.Firstly,the GAN-based model is more effective for the seasonal-scale extraction and diagnosis of the subsurface stratification,especially in the Luzon Strait and coastal shelf sea areas,in which stronger nonlinearities arise from the Kuroshio intrusion or complex coastal processes dominate the ocean subsurface dynamics.Secondly,the vertical heat pump and cold suction effects in the ocean's upper layers induced by the passage of a typhoon can be reflected more reasonably based on the synoptic-scale analysis with the proposed model.Furthermore,the underwater 3D structure of mesoscale eddies can be skillfully captured by AIGAN(Attention and Inception GAN),which can extract more refined eddy patterns with stronger recognition capability compared with the statistics-based MODAS.The present study can be extended to further explore the subsurface characteristics of the internal variability in the South China Sea.
基金financial support from the Major Scientific and Technological Projects of CNPC(Award No.ZD2019-183-007)。
文摘High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant and salt-resistant foaming agents is commonly used to control gas channeling.The feasibility of the compound system of dodecyl hydroxyl sulfobetaine(HSB12)andα-olefin sulfonate(AOS)as foaming agent for sandstone reservoir was studied at 130℃and 22×10^(4)mg/L.The results showed that the foaming agent(HSB12 and AOS were compounded in a 6:1 mass ratio,in this article,this foaming agent is simply referred to as SA61)had good solubility in 22×10^(4)mg/L simulated formation water.Besides,the foaming volume of SA61 and HSB12 was similar,but the foam decay half-life of SA61was 10-25 times higher than that of HSB12.The foaming performance of SA61 on the surface of quartz sand remained above 90%of that before adsorption.The strong interaction between HSB12 and AOS in the compound system SA61 was demonstrated by surface rheological measurements and NMR studies of surfactants.The results of co re flow test showed that SA61 had better mobility control ability than HSB12under the same surfactant concentration.In addition,SA61 showed a selective mobility reduction in2005.30 and 632.00 mD cores.The above research results can guide the selection and application of foaming agent in clastic reservoir.
基金supported by the National Natural Science Foun-dation of China(12362032)the Key Research and Development Pro-gram of Gansu Province-Social Development(23YFFA0063).
文摘In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province,triaxial compression tests and scanning electron microscopy(SEM)analysis experiment were conducted to explore the effects of moisture content,confining pressure,and temperature on the stress-strain characteristics and failure modes of frozen soil,as well as the changes in the internal microstructure of the sample.The experimental results show that the strength of frozen sulfate saline soil first increases and then decreases with the increase of moisture content,and the maximum strength corresponds to a moisture content of 15%.The changes in confining pressure and strength have the same trend.The lower the temperature,the greater the strength of the sample.During the entire loading process,the specimens undergo a gradual transition from volume shrinkage to volume expansion.Due to the strain harden behavior of the stress-strain curve throughout the entire loading process,the failure mode of the specimens is plastic failure.The internal microstructure of the sample gradually transitions from point-point contact and edge-point contact before shearing to edge-surface contact and edge-edge contact after shearing,and the pore size inside the sample increases after shearing,with a loose arrangement of the particle skeleton.The above research conclusions can lay a certain theoretical foun-dation for the engineering design and construction of sulfate saline soil in cold and arid areas.
基金Supported by Natural Science Foundation of the Inner Mongolia Autonomous Region(2020MS04001)Inner Mongolia Autonomous Region Science and Technology Program Project+1 种基金Hetao College Science and Technology Research Project(HYYB202303)Hetao College Science and Technology Innovation Team.
文摘A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying scenarios including nitrogen fertilization rates,irrigation rates,and air temperatures in the Hetao Irrigation District(HID)over the 38-year period.DAYCENT model was used to predict carbon dioxide(CO_(2))fluxes from cultivated soils in the HID,Inner Mongolia from^(2)023 to 2060(the year of achieving the"carbon neutrality"goal)in this study.Results showed that mean soil CO_(2)fluxes in the sunflower field[1035.13 g/(m^(2).yr)]were significantly lower than those in the maize field[1405.54 g/(m^(2).yr)].An increase in nitrogen fertilization rate led to a significant escalation in soil CO_(2)fluxes.Moreover,elevating irrigation rates for washing salts by irrigation(WSBI)diminished soil CO_(2)fluxes in the sunflower field while amplifying them in the maize field.A rise in air temperature resulted in an increase in soil CO_(2)fluxes from the maize field,with annual increases observed,but a reduction in soil CO_(2)fluxes from the sunflower field.The sunflower fields in the HID have a more substantial advantage than the corn fields in mitigating soil CO_(2)emissions.
基金supported by the National Natural Science Foundation of China(Nos.62275131,62231005 and 62105164)the Natural Science Foundation of Tianjin(Nos.21JCQNJC00210,22JCQNJC01540 and 21JCYBJC00080)。
文摘We propose an in-fiber Michelson-Fabry-Perrot(M-FP)hybrid interferometer for the simultaneous measurement of seawater temperature and salinity.The sensor head consists of two parallel hetero Fabry-Perot(FP)cavities fabricated on the end face of the twin core fiber(TCF).A fiber fusion taper is used to split and recouple the light in the two cores.In this case,the Vernier effect can be obtained which can greatly enhance the sensitivity and solve the problem of temperature cross-sensitivity.Different from the traditional demodulation method based on envelop detection,we employed frequency domain decomposition method(FDDM)to demodulate the sensing signal.The simulation results indicate that the proposed sensor has high sensitivity to salinity and temperature.Thanks to the merits of high sensitivity,ease of fabrication and small footprint,the proposed seawater temperature and salinity sensor would have potential applications in marine science,food industry and ocean ranching.
基金supported by the Na-tional Natural Science Foundation of China(Nos.62175105,61875086)Fundamental Research Funds for the Cen-tral Universities of China(No.ILB240041A24)。
文摘A novel temperature and salinity discriminative sensing method based on forward Brillouin scattering(FBS)in 1060-XP single-mode fiber(SMF)is proposed.The measured frequency shifts corresponding to different radial acoustic modes in 1060-XP SMF show different sensitivities to temperature and salinity.Based on the new phenomenon that different radial acoustic modes have different frequency shift-temperature and frequency shift-salinity coefficients,we propose a novel method for simultaneously measuring temperature and salinity by measuring the frequency shift changes of two FBS scattering peaks.In a proof-of-concept experiment,the temperature and salinity measurement errors are 0.12℃and 0.29%,respectively.The proposed method for simultaneously measuring temperature and salinity has the potential applications such as ocean surveying,food manufacturing and pharmaceutical engineering.
基金supported by the National Natural Science Foundation of China(Grant number:41440027)。
文摘The formation mechanism of high salinity geothermal water is significant for utilizing geothermal resources and mineral resources.The high salinity in geothermal water may be derived from the geothermal mother fluid or from the evaporite dissolution.It is difficult to distinguish between these two sources because they may have similar hydrochemistry.In this paper,water chemistry and stable isotopes were used to explore the high salinity geothermal water in Yanchanghe geothermal field,central China.It is a lowtemperature hydrothermal system in the inland karst area.The thermal water is Cl-Na type with high salinity(TDS>8,400 mg/L).The modified silicon thermometer is more suitable and the reasonable result is about 58.8℃.The maximum circulation depth is 1.9 km.Using the temperature of hot and cold water to estimate the mixing ratio is 58%-81%.Saturation index(SI),Na/1000-K/100-Mg1/2 and Gibbs diagram suggest that the main source of salt in geothermal water is derived from the evaporite dissolution,which provides Cl-of 11,264-31,279 mg/L and Na+of 9,272-21,236 mg/L.We found the combination of temperature and hydrogeochemistry can be used to investigate the formation mechanism and mixing process of high-salinity geothermal water formed in a karst low-temperature hydrothermal system.
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 by the Tianjin Science and Technology Plan Project(No.22JCQNJC01280)the Central Funds Guiding the Local Science and Technology Development of Hebei Province(Nos.226Z1001G and 226Z1012G)+1 种基金the National Natural Science Foundation of China(No.52002109,52071124)the Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001).
文摘Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural applications.The emerging face-centered cubic medium-entropy alloys(MEAs)demonstrate outstanding mechanical properties at both ambient and cryogenic temperatures.They are anticipated to extend their applicability to elevated temperatures,owing to their inherent advantages in leveraging multiple strengthening and deformation mechanisms.Here,a dual heterostructure,comprising of heterogeneous grain structure with heterogeneous distribution of the micro-scale Nb-rich Laves phases,is introduced in a CrCoNi-based MEA through thermo-mechanical processing.Additionally,a high-density nano-coherentγ’phase is introduced within the grains through isothermal aging treatments.The superior thermal stability of the heterogeneously distributed precipitates enables the dual heterostructure to persist at temperatures up to 1073 K,allowing the MEA to maintain excellent mechanical properties across a wide temperature range.The yield strength of the dual-heterogeneous-structured MEA reaches up to 1.2 GPa,1.1 GPa,0.8 GPa,and 0.6 GPa,coupled with total elongation values of 28.6%,28.4%,12.6%,and 6.1%at 93 K,298 K,873 K,and 1073 K,respectively.The high yield strength primar-ily stems from precipitation strengthening and hetero-deformation-induced strengthening.The high flow stress and low stacking fault energy of the dual-heterogeneous-structured MEA promote the formation of high-density stacking faults and nanotwins during deformation from 93 K to 1073 K,and their density increase with decreasing deformation temperature.This greatly contributes to the enhanced strainhardening capability and ductility across a wide temperature range.This study offers a practical solution for designing dual-heterogeneous-structured MEAs with both high yield strength and large ductility across a wide temperature range.
基金supported by the National Nature Science Foundation of China(Nos.22305066 and 52372041).
文摘High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.
基金supported by the Guangdong Special Support ProgramProject(No.2021JC060580)the Foshan Innovation Team Project(No.2130218003140).
文摘In this study,the effects of different salinity gradients and addition of compatible solutes on anaerobic treated effluent water qualities,sludge characteristics and microbial communities were investigated.The increase in salinity resulted in a decrease in particle size of the granular sludge,which was concentrated in the range of 0.5-1.0 mm.The content of EPS(extracellular polymeric substances)in the granular sludge gradually increased with increasing salinity and the addition of betaine(a typical compatible solute).Meanwhile,the microbial community structure was significantly affected by salinity,with high salinity reducing the diversity of bacteria.At higher salinity,Patescibacteria and Proteobacteria gradually became the dominant phylum,with relative abundance increasing to 13.53%and 12.16%at 20 g/L salinity.Desulfobacterota and its subordinate Desulfovibrio,which secrete EPS in large quantities,dominated significantly after betaine addition.Their relative abundance reached 13.65%and 7.86%at phylum level and genus level.The effect of these changes on the treated effluent was shown as the average chemical oxygen demand(COD)removal rate decreased from 82.10%to 79.71%,78.01%,68.51%and 64.55%when the salinity gradually increased from 2 g/L to 6,10,16 and 20 g/L.At the salinity of 20 g/L,average COD removal increased to 71.65%by the addition of 2 mmol/L betaine.The gradient elevated salinity and the exogenous addition of betaine played an important role in achieving stability of the anaerobic system in a highly saline environment,which provided a feasible strategy for anaerobic treatment of organic saline wastewater.
基金supported by the China Postdoctoral Science Foundation(No.2020M671624)the State Key Laboratory of Pollution Control and Resource Reuse(No.PCRRF20011).
文摘Two anaerobic ammonia oxidation(anammox)systems,one with adding nano-scale zerovalent iron modified biochar(nZVI@BC)and the other with adding biochar,were constructed to explore the feasibility of nZVI@BC for enhancing the resistance of low-nitrogen anammox processes to low temperatures.The results showed that the average nitrogen removal efficiency with nZVI@BC addition at lowtemperatureswas maintained at about 80%,while that with biochar addition gradually decreased to 69.49%.The heme-c content of biomass with nZVI@BC was significantly higher by 36.60%-91.45%.Additional,nZVI@BC addition resulted in more extracellular polymeric substances,better biomass granulation,and a higher abundance of anammox bacteria.In particularly,anammox genes hzsA/B/C,hzo and hdh played a pivotal role in maintaining nitrogen removal performance at 15℃.These findings suggest that nZVI@BC has the potential to enhance the resistance of low-nitrogen anammox processes to low temperatures,making it a valuable approach for practical applications in low-nitrogen and low-temperature wastewater treatment.
基金supported by the National Natural Science Foundation of China(32372223)the National Key Research and Development Program of China(2022YFD2301404)+1 种基金the College Students'Innovationand Entrepreneurship Training Program of Anhui Province,China(S202210364136)the Natural Science Research Project of Anhui Educational Committee,China(2023AH040133).
文摘Low temperature(LT)in spring has become one of the principal abiotic stresses that restrict the growth and development of wheat.Diverse analyses were performed to investigate the mechanism underlying the response of wheat grain development to LT stress during booting.These included morphological observation,measurements of starch synthase activity,and determination of amylose and amylopectin content of wheat grain after exposure to treatment with LT during booting.Additionally,proteomic analysis was performed using tandem mass tags(TMT).Results showed that the plumpness of wheat grains decreased after LT stress.Moreover,the activities of sucrose synthase(SuS,EC 2.4.1.13)and ADP-glucose pyrophosphorylase(AGPase,EC 2.7.7.27)exhibited a significant reduction,leading to a significant reduction in the contents of amylose and amylopectin.A total of 509 differentially expressed proteins(DEPs)were identified by proteomics analysis.The Gene Ontology(GO)enrichment analysis showed that the protein difference multiple in the nutritional repository activity was the largest among the molecular functions,and the up-regulated seed storage protein(ssP)played an active role in the response of grains to LT stress and subsequent damage.The Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis showed that LT stress reduced the expression of DEPs such as sucrose phosphate synthase(SPS),glucose-1-phosphate adenylyltransferase(glgC),andβ-fructofuranosidase(FFase)in sucrose and starch metabolic pathways,thus affecting the synthesis of grain starch.In addition,many heat shock proteins(HsPs)were found in the protein processing in endoplasmic reticulum pathways,which can resist some damage caused by LT stress.These findings provide a new theoretical foundation for elucidating the underlying mechanism governing wheat yield developmentafterexposuretoLTstress inspring.
基金supported by the National Key R&D Program of China under Grant 2024YFE0203500Xiaomi Young Talents Program。
文摘In the applications such as food production,the environmental temperature should be measured continuously dur-ing the entire process,which requires an ultra-low-power temperature sensor for long-termly monitoring.Conventional tempera-ture sensors trade the measurement accuracy with power consumption.In this work,we present a battery-free wireless tempera-ture sensing chip for long-termly monitoring during food production.A calibrated oscillator-based CMOS temperature sensor is proposed instead of the ADC-based power-hungry circuits in conventional works.In addition,the sensor chip can harvest the power transferred by a remote reader to eliminate the use of battery.Meanwhile,the system conducts wireless bidirectional communication between the sensor chip and reader.In this way,the temperature sensor can realize both a high precision and battery-free operation.The temperature sensing chip is fabricated in 55 nm CMOS process,and the reader chip is imple-mented in 65 nm CMOS technology.Experimental results show that the temperature measurement error achieves±1.6℃ from 25 to 50℃,with battery-free readout by a remote reader.
基金the National Natural Science Foundation of China(No.22279070[L.Wang]and U21A20170[X.He])the Ministry of Science and Technology of China(No.2019YFA0705703[L.Wang])。
文摘Lithium-ion batteries(LIBs)face significant limitations in low-temperature environments,with the slow interfacial de-solvation process and the hindered Li+transport through the interphase layer emerging as key obstacles beyond the issue of ionic conductivity.This investigation unveils a novel formulation that constructs an anion-rich solvation sheath within strong solvents,effectively addressing all three of these challenges to bolster low-temperature performance.The developed electrolyte,characterized by an enhanced concentration of contact ion pairs(CIPs)and aggregates(AGGs),facilitates the formation of an inorganic-rich interphase layer on the anode and cathode particles.This promotes de-solvation at low temperatures and stabilizes the electrode-electrolyte interphase.Full cells composed of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)and graphite,when equipped with this electrolyte,showcase remarkable cycle stability and capacity retention,with 93.3% retention after 500 cycles at room temperature(RT)and 95.5%after 120 cycles at -20℃.This study validates the utility of the anion-rich solvation sheath in strong solvents as a strategy for the development of low-temperature electrolytes.
基金financially supported by the Beijing Natural Science Foundation,China (No.JQ21028)the National Natural Science Foundation of China (Nos.52311530070,52278326,and 52004015)+2 种基金the Major National Science and Technology Project for Deep Earth,China (No.2024ZD1003805)the Project from PetroChina RIPED:the Study on the evolution law of Mineral Structure and Rock Mechanical Properties Under Ultra-High Temperature Conditions (No.2022-KFKT-02)the Fundamental Research Funds for the Central Universities of China (No.FRF-IDRY-20-003,Interdisciplinary Research Project for Young Teachers of USTB)。
文摘Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and caprock under in-situ high-temperature and confine-ment conditions is of considerable importance. Compared to conventional mechanical experiments on rock samples after high-temperat-ure treatment, in-situ high-temperature experiments can more accurately characterize the behavior of rocks in practical engineering,thereby providing a more realistic reflection of their mechanical properties. In this study, an in-situ high-temperature triaxial compressiontesting machine is developed to conduct in-situ compression tests on sandstone at different temperatures(25, 200, 400, 500, and 650℃)and confining pressures(0, 10, and 20 MPa). Based on the experimental results, the temperature-dependent changes in compressivestrength, peak strain, elastic modulus, Poisson's ratio, cohesion, and internal friction angle are thoroughly analyzed and discussed. Resultsindicate that the mass of sandstone gradually decreases as the temperature increases. The thermal conductivity and thermal diffusivity ofsandstone exhibit a linear relationship with temperature. Peak stress decreases as the temperature rises, while it increases with higher con-fining pressures. Notably, the influence of confining pressure on peak stress diminishes at higher temperatures. Additionally, as the tem-perature rises, the Poisson's ratio of sandstone decreases. The internal friction angle also decreases with increasing temperature, with 400℃ acting as the threshold temperature. Interestingly, under uniaxial conditions, the damage stress of sandstone is less affected by tem-perature. However, when the confining pressure is 10 or 20 MPa, the damage stress decreases as the temperature increases. This study en-hances our understanding of the influence of in-situ high-temperature and confinement conditions on the mechanical properties of sand-stone strata. The study also provides valuable references and experimental data that support the development of low-to medium-maturityoil shale resources.
基金supported by the National Natural Science Foundation of China(72072169)the Fundamental Re-search Funds for the Central Universities(YD2040002015).
文摘The impact of extreme temperatures on the health of individuals in different organizations remains uncertain.We employed stratified analyses to examine the impacts of summer(April-September)daily maximum temperatures and winter(October-March)daily minimum temperatures on blood pressure and lipid profiles across government staff,com-pany employees,and researchers.We examined 209,477 physical examination records from a physical examination center in the First Affiliated Hospital of USTC from 2017 to 2021.Employing a segmented regression model within the frame-work of generalized linear regression(GLM),we examined the causal impact of extreme temperatures on health outcomes.Additionally,sensitivity analyses were conducted via distributed lag nonlinear models(DLNMs),with a focus on ob-serving the long-term effects over a period of 21 days.Our findings indicate that government staff face increased health risks during extremely low temperatures,regardless of the season.Compared with participants experiencing median tem-peratures,government staff exposed to extremely low temperatures(below the 10th percentile,below 24℃)in the sum-mer presented maximum increases of 2.32 mmHg(95%CI:1.542-3.098)in diastolic blood pressure and 6.481 mmHg(95%CI:5.368-7.594)in systolic blood pressure.In winter,government staff exposed to temperatures below the 10th per-centile(below 1℃)demonstrated maximum increases of 0.278 mmol/L(95%CI:0.210-0.346)in total cholesterol,0.153 mmol/L(95%CI:0.032-0.274)in triglycerides,and 0.077 mmol/L(95%CI:0.192-0.134)in low-density lipoprotein.Conversely,warm winters benefit company employees,whereas researchers exhibit lower sensitivity to temperature changes in winter.The maximum temperatures in summer and minimum temperatures in winter had greater impacts on in-dividuals.Small temperature fluctuations impact health more than large changes do.Notably,both the maximum and min-imum temperatures were better predictors of health outcomes than the daily average temperature was.Blood pressure con-sistently displayed significant associations with temperature across all three groups,with extremely low temperatures in-creasing the risk and extremely high temperatures reducing it.However,the relationship between temperature and blood lipids is complex.
基金supported by the National Natural Science Foundation of China(Nos.22208221,22178221)the Natural Science Foundation of Guangdong Province(Nos.2024A1515011078,2024A1515011507)+1 种基金the Shenzhen Science and Technology Program(Nos.JCYJ20220818095805012,JCYJ20230808105109019)the Start-up Research Funding of Shenzhen University(No.868-000001032522).
文摘The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design concept of eutectic electrolyte is presented by mixing long chain polymer molecules,polyethylene glycol dimethyl ether(PEGDME),with H_(2)O based on zinc trifluoromethyl sulfonate(Zn(OTf)2),to reconstruct the Zn^(2+)solvated structure and in situ modified the adsorption layer on Zn electrode surface.Molecular dynamics simulations(MD),density functional theory(DFT)calculations were combined with experiment to prove that the long-chain polymer-PEGDME could effectively reduce side reactions,change the solvation structure of the electrolyte and priority absorbed on Zn(002),achieving a stable dendrite-free Zn anode.Due to the comprehensive regulation of solvation structure and zinc deposition by PEGDME,it can stably cycle for over 3200 h at room temperature at 0.5 mA/cm^(2)and 0.5 mAh/cm^(2).Even at high-temperature environments of 60℃,it can steadily work for more than 800 cycles(1600 h).Improved cyclic stability and rate performance of aqueous Zn‖VO_(2)batteries in modified electrolyte were also achieved at both room and high temperatures.Beyond that,the demonstration of stable and high-capacity Zn‖VO_(2)pouch cells also implies its practical application.
基金funding support from the National Natural Science Foundation of China(Grant No.52274082)the Program of Qingjiang Excellent Young Talents,Jiangxi University of Science and Technology(Grant No.JXUSTQJBJ2020003)the Innovation Fund Designated for Graduate Students of Jiangxi Province(Grant No.YC2023-B215).
文摘The roughness of the fracture surface directly affects the strength,deformation,and permeability of the surrounding rock in deep underground engineering.Understanding the effect of high temperature and thermal cycle on the fracture surface roughness plays an important role in estimating the damage degree and stability of deep rock mass.In this paper,the variations of fracture surface roughness of granite after different heating and thermal cycles were investigated using the joint roughness coefficient method(JRC),three-dimensional(3D)roughness parameters,and fractal dimension(D),and the mechanism of damage and deterioration of granite were revealed.The experimental results show an increase in the roughness of the granite fracture surface as temperature and cycle number were incremented.The variations of JRC,height parameter,inclination parameter and area parameter with the temperature conformed to the Boltzmann's functional distribution,while the D decreased linearly as the temperature increased.Besides,the anisotropy index(Ip)of the granite fracture surface increased as the temperature increased,and the larger parameter values of roughness characterization at different temperatures were attained mainly in directions of 20°–40°,60°–100°and 140°–160°.The fracture aperture of granite after fracture followed the Gauss distribution and the average aperture increased with increasing temperature,which increased from 0.665 mm at 25℃to 1.058 mm at 800℃.High temperature caused an uneven thermal expansion,water evaporation,and oxidation of minerals within the granite,which promoted the growth and expansion of microfractures,and reduced interparticle bonding strength.In particular,the damage was exacerbated by the expansion and cracking of the quartz phase transition after T>500℃.Thermal cycles contributed to the accumulation of this damage and further weakened the interparticle bonding forces,resulting in a significant increase in the roughness,anisotropy,and aperture of the fracture surface after five cycles.
