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Electrocaloric effect (ECE) refrigeration stands out as a promising alternative to conventional compression refrigeration owing to its potential for miniaturization, high energy conversion efficiency, cost-effectiveness, and environmental friendliness. However, the practical applications of ECE refrigeration in lead-free ceramics face limitations due to the challenge of achieving a substantial adiabatic temperature change (Δ T) and a wide operating temperature span (T span). In this study, we tackle this challenge by introducing rare-earth Sm3+ ions into Ba(Ti 0 · 90 Sn 0.10)O 3 (BTSn) ceramics to enhance their ECE stability. We comprehensively investigate the structural, dielectric, and ECE properties of (Ba 1−3 x /2 Sm x) (Ti 0 · 9 Sn 0.1)O 3 (BSmTSn, x = 0−0.03) ceramics. Our findings reveal that the incorporation of Sm3+ ions leads to a reduction in the temperature at which the permittivity reaches its maximum, accompanied by an increased dispersion compared to undoped BTSn ceramics. Particularly noteworthy is the achievement of a Δ T of 0.9 K with a T span of 55.5 °C in the x = 0.005 composition. Furthermore, increasing x to 0.01 enables the realization of a wide T span of 70 °C, starting from 30 °C. These significant enhancements in the T span across all BSmTSn ceramics, facilitated by the introduction of Sm3+ ions, present a promising strategy for optimizing the ECE performance of BaTiO 3 -based ceramics. [ABSTRACT FROM AUTHOR]

• Diagram of solubility in the studied quaternary water-salt system at the different temperatures was calculated on the base of classical Pitzer's equations. • Temperature of double salt formation in ternary and quaternary systems was determined. • Classification of non-variant points was provided. Diagram of solubility in quaternary water-salt system N a + , N i 2 + / / C l - , S O 4 2 - - H 2 O in the temperature range −5 ÷ 90 °С was calculated on the base of classical Pitzer's equations. Linear temperature approximation of solubility products of solid phases was used. [ABSTRACT FROM AUTHOR]

The role of thermal cycling on the deformation behaviour and microscopic damage mechanisms of 316L stainless steel are clarified through isothermal fatigue (IF) and thermomechanical fatigue (TMF) tests under various temperature ranges. Corresponding microscopic damage mechanism is revealed based on the analysis of dislocation structure, plastic deformation, and crack initiation mode. Results show that the introduction of thermal cycling, as well as an increase in average temperature and temperature difference, result in the saturation of cyclic peak stresses, a decrease in fatigue life, and an intensification of dynamic strain ageing (DSA). Notably, under TMF loading at the same average temperature, there is a significant recovery process compared to IF. High-density dislocations transform into low-energy dislocation structures through cross-slip, indicating a pronounced recovery phenomenon. At large temperature differences and high average temperatures, the accumulation of dislocation tangles at grain boundaries and the formation of dislocation cell structures lead to severe incoherence in plastic deformation and the accumulation of damage. Furthermore, the introduction of thermal cycling and an increase in temperature differences also induce severe creep damage. It is observed that the dominant crack initiation mode changes from fatigue-dominated transgranular cracking to oxidation-induced intergranular cracking as the average temperature increases. Finally, a modified life prediction model is developed by incorporating thermal plastic strain energy to reflect the effect of thermal cycling on TMF behaviour. [ABSTRACT FROM AUTHOR]

The seasonal freeze-thaw environment is a primary factor contributing to the deterioration of manually excavated disturbed rock masses on reservoir bank slopes in highland alpine areas. To investigate the mechanical properties and damage deterioration mechanism of excavation-unloading rock under seasonal freeze-thaw environment in cold region, the freeze-thaw cycle tests with different temperature difference levels (−10–10 °C, −15–25 °C, −20–40 °C) and different cycle times (0,10,20,30) were simulated for the triaxial unloading damaged marble. Then, the mechanical parameters of unloaded marble after freezing and thawing were obtained by uniaxial compression and triaxial compression tests, and the influence laws of temperature ranges, number of freezing and thawing cycles and confining pressure on the mechanical properties of unloaded marble were analyzed. Finally, the damage model of unloaded marble considering freeze-thaw action was established. The results show that the strength of unloaded marble is significantly weakened under the combined effect of F-T (freezing and thawing) and loading, and that the deterioration effect of the number of F-T cycles is stronger than that of the temperature ranges. The increase in the confining pressure increased the compressive strength and elastic modulus of the unloaded marble, and suppressed the damage of the unloaded marble after the freeze-thaw treatment. The porosity of the unloaded marble developed gradually and increased exponentially with the increase of the number of freeze-thaw cycles, the compressive strength and elastic modulus had a negative exponential relationship with the number of freeze-thaw cycles, and the shear strength parameter had a quadratic polynomial relationship with the number of freeze-thaw cycles. In addition, the softening mechanism of unloaded marble by natural water plays a key role in the process of freeze-thaw cycle, and the damage model considering freeze-thaw is established, and the theoretical curves are well matched with the experimental results. The outcomes of this study hold significant theoretical and engineering importance for evaluating the stability of excavated unloaded rock in highland alpine regions. • Unloaded marble mechanical properties tested under freeze-thaw and confining pressures. • The coupling effects of different freeze-thaw temperature ranges, cycles and confining pressures were analyzed. • A model of unloaded marble considering freezing-thawing and load was established. [ABSTRACT FROM AUTHOR]

In this paper a low complexity, sub-1V, reference voltage generator with low voltage sensitivity over PVT variation and high power supply rejection ratio (PSRR) is proposed. It consists of a traditional bandgap reference core where resistors are used for generating both the PTAT and CTAT currents, which are then added forming a temperature-independent current. A new 1 V modified folded cascode operational amplifier is proposed and used in the main bandgap's loop resulting in low offset, high loop gain and adequate loop phase margin of 58.9°. The loop consists of only two inverting stages and the circuit can be integrated entirely without the need of external large capacitors for frequency compensation. A regulated cascode current source is employed for accurately mirroring of the core temperature-independent current to a resistive load, where the reference voltage is generated. The proposed circuit was simulated in SPECTRE achieving an output reference voltage variation of 3.62%, without trimming, over process variation corners with ±10% variation of the 1 V power supply voltage and within the industrial temperature range, from −40 °C to 125 °C. The temperature coefficient from −40 °C to 125 °C is 6.81 ppm/°C at 1 V at the typical process corner. The PSRR at 1 Hz and the output RMS noise within a bandwidth of 100 MHz are −69.85 dB and 279 μV RMS, respectively, at the typical process corner, at a supply voltage of 1 V and temperature of 27 °C. Typical power consumption is 452 μA at 1 V. [ABSTRACT FROM AUTHOR]

• Energy and power densities quantitation of Li-ion cells (NMC NCA) from −20 to 55 °C. • Investigation and validation of an efficient model only based on datasheet at 25 °C. • Extension of this electro-thermal model to wider temperature and power ranges. • Proposition of a non-isothermal Ragone plot to select the most suitable Li-ion cells. Ragone plot is a conventional tool to compare different energy storage systems in terms of energy and power densities. The selection of the most suitable Li-ion technology for a given application is usually based on the specific energy and power extracted from datasheets at ambient temperatures (25 °C). However, these values are highly temperature-dependent. This study investigates experimentally and via numerical simulations a quantification of the energy and power densities for two different Li-ion chemistry cells in a wide operating temperature range. The experimental results reveal that these values determined from constant current discharge are approximately 15% higher than those determined for a constant power discharge. Therefore, a simple and efficient coupled electrical–thermal model based on an equivalent circuit model (ECM) is proposed, which is able to estimate the voltage, temperature, and available discharged energy of 18,650 Li-ion cells with a good accuracy. Moreover, all parameters in the model can be directly identified with manufacturer's datasheets at 25 °C. Then, the proposed Ragone plot model can be extended to wider temperature and power ranges. The relative error of the simulated energy density is below 2% for both technologies for all operating conditions from – 20 °C to 55 °C. Thus, a non-isothermal Ragone plot is established by considering the thermal effect for the first time. The proposed method could be employed as a conception aid tool for the selection of Li-ion cells in a system design process. [ABSTRACT FROM AUTHOR]

In recent years, water-side free cooling has been broadly applied in data centers to lessen the high cost of energy consumption. The energy-saving opportunities of free cooling have been recognized by numerous studies across the world. In this paper, the field test and energy performance evaluation were performed in an operational data center with water-side free cooling, located in Chongqing, China. Existing problems were found during tests, including the insufficient cooling capacity of towers in wintertime and the inability to activate partial-free cooling. The results of the tests show that the reduction in Power Usage Effectiveness (PUE) is much lower than the expected. To understand the marked discrepancies, the performance of the cooling tower was discussed in terms of the approach temperature and actual cooling capacity. The maximum cooling capacity in winter is only about 50 % of the rated. With the consideration of the cooling tower configuration performance in different climate conditions, the conservative energy effects were calculated in 34 provincial cities of China. To prolong the hours available, optimized operation schemes of cooling towers are presented. The available hours for free cooling could be increased from 730 h to 1300 h when operating at 67 % of rated flow rate, resulting in a decrease in the energy saving of chillers between 8.44 % and 21.05 %. [ABSTRACT FROM AUTHOR]

A room temperature curable heat-resistant adhesive with broad working temperature range was prepared through organic and inorganic modification. The preceramic polymethylsiloxane showed low bonding strength for silicon carbide from 400 °C to 600 °C because of the decomposition of polymer network. So the modification with epoxy resin was used to generate strong blending and copolymerization network which decomposed at higher temperature over 500 °C. The ceramization of active fillers and preceramic polymer compensated the bonding strength with rising temperature, thus eliminating the weak stage from 400 °C to 600 °C. The modification with fillers greatly improved its bonding strength at high temperature over 1000 °C. Consequently, the modified adhesive exhibited outstanding bonding strength tested at room temperature between 9.29 ± 0.56 MPa and 37.28 ± 1.33 MPa after heat-treatment from 25 °C to 1500 °C and the bonding strength directly tested at the temperature from 25 °C to 800 °C over 8.21 ± 0.40 MPa. The adhesive shows the potential to extend the application for engineering ceramic joining. [ABSTRACT FROM AUTHOR]

• MPCM slurry viscosity and thermal conductivity affect its heat transfer. • Spraying MPCM slurry weakens the above-mentioned adverse effects. • The working and phase change temperature ranges of the used MPCM slurry are matched. • Faster cooling yields more supercooling and a wider phase change temperature range. • Heat–mass transfer is better for MPCM slurry than for sprayed pure water. A spraying system was constructed with a microencapsulated phase change material (MPCM) slurry as the working medium to weaken the adverse effects of the slurry's high viscosity and low thermal conductivity on heat transfer in a wall tube heat exchanger. The temperature distributions of pure water and MPCM slurry were first obtained through infrared thermal imaging in spraying. Furthermore, the latent heat use of MPCM slurry was investigated through a new method based on the temperature properties of the phase change fluid, in which the working and phase change temperature ranges are matched. The heat-mass transfer characteristics are compared and discussed with those of the base fluid, and the latent heat use of 10wt% MPCM slurry containing the core material n-docosane (C 22 H 46). The experimental results indicate that the phase change enables the MPCM slurry droplets to maintain a higher temperature than a fluid with no phase change or base fluid. Different application modes (static and spraying) have correspondingly different phase change temperature ranges owing to supercooling, and the degree of matching between the working and phase change temperature ranges has a critical impact on the latent heat use of the MPCM slurry. Finally, comparing the heat transfer coefficients and Lewis numbers between the base liquid and MPCM slurry reveals that the phase change not only enhances the heat transfer but also slightly reduces water evaporation compared with pure water spraying. [ABSTRACT FROM AUTHOR]

• Setting the incubation temperature range (ITR) is essential for experiments on Q 10. • We addressed this using 54 soils from typical ecosystems under nine ITR scenarios. • ITRs have a significant impact on Q 10 in different ecosystem or soil types. • The growing season average temperature range is the optimum ITR across ecosystems. • ITR should be considered as a key parameter for Q 10 estimation in the future. Temperature sensitivity (Q 10) of soil organic matter (SOM) decomposition is an essential parameter that reflects the feedback relationship between climate warming and atmospheric CO 2 concentration and plays a key role in accurately estimating changes in soil carbon pools and their feedback to climate change. Setting the incubation temperature range (ITR) scenario is essential to accurately estimate the temperature sensitivity of SOM decomposition; however, this has been widely ignored. To address this issue, we conducted a systematic incubation experiment using 54 soils covering the most typical ecosystems in China and nine ITR scenarios. The results showed that ITR scenarios had a significant effect on Q 10 in different ecosystems and soil types. Combining the results of fitting mean annual temperature (MAT) to the Q 10 of different ITR and the interpretation rate of factors (including climate, soil, and microbial community composition) to the Q 10 of different ITR, the results indicate that the growing season average temperature range (GSA) scenario had better performance than the other ITR scenarios and should be the optimum ITR scenario. Furthermore, the variation of main influence factors of Q 10 across different ecosystems should be accounted for to accurately predict the feedback between soil C cycle and climate change. Overall, our findings highlight the importance of the ITR for the estimates of Q 10 using widespread experimental data, providing a reference for subsequent experiments accurately measure Q 10 , as well as compare and compile global data to better predict the feedback between the global carbon cycle and climate change. [ABSTRACT FROM AUTHOR]

Understanding how germination traits can influence the distribution pattern of adult plants is still an important issue for seed ecologists and biologists. Here, we evaluated if seed germination responses to abiotic factors may be related to the occurrence of two Moquiniastrum species in different phytophysiognomies from the Brazilian savanna. To evaluate if germination responses are distinct between species, seeds of M. barrosoae (common to typical savanna) and M. polymorphum (common to typical and forested savanna) were set to germinate under different constant (5 to 40 °C) and alternating (15–30, 20–30, 25–30 and 25–35 °C) temperature regimes in light and dark conditions, different red:far-red ratios (0.1, 0.5, 2.0 and 7.2 R:FR) of light, and water availability (0 to −1.0 MPa) in controlled experiments. Seed germination responses were distinct between species, with M. polymorphum presenting higher germinability over a wider temperature range, with lower light requirement for germination, less sensitivity to alteration of R:FR ratios and higher tolerance to water limitation compared to M. barrosoae , which presented more specific environmental requirements to seed germination. Therefore, we demonstrate that seed germination responses may contribute to the distribution pattern observed in adult plants, since the more widely distributed species ( M. polymorphum ) presented higher germinability over a broader range of environmental conditions, which may enable this species to occur in different phytophysiognomies compared to the species with the more restricted distribution area ( M. barrosoae ). [ABSTRACT FROM AUTHOR]

Naranga aenescens Moore is an important insect pest found in rice paddy field. We investigated the development periods of N. aenescens egg, larva, pupa, and total immature insects at eight constant temperatures: 15.0 °C, 17.5 °C, 20.0 °C, 22.5 °C, 25.0 °C, 27.5 °C, 30.0 °C, and 32.5 °C. N. aenescens developed successfully from the egg stage to the adult stage at all the tested temperatures except 15.0 °C. The developmental time of each life stage was significantly influenced by temperatures. The developmental rate of N. aenescens increased as the temperature increased from 15.0 °C to 30.0 °C but declined at 32.5 °C, except in the pupa stage. The lower developmental threshold (LDT) and the thermal constant (K) was estimated using linear regression. The higher temperature threshold and the lower temperature threshold were calculated using two nonlinear functions. LDT and K from egg to adult emergence were 12.01 °C and 330.84 degree days, respectively. The temperature range of N. aenescens from the lower developmental threshold to the higher developmental threshold using a performance model (24.03) was wider than that determined using the Sharpe–Schoolfield–Ikemoto model (19.77). Developmental completion of N. aenescens was described using a two-parameter Weibull distribution model. Adult emergence frequency of N. aenescens over a full range of constant temperatures was simulated using developmental rate functions and the Weibull function. Biological characteristics of N. aenescens populations from different geographic areas were discussed. [ABSTRACT FROM AUTHOR]

• Frosting mechanisms from general-low to ultra-low temperatures were investigated. • Frost morphology and properties were identified in terms of frosting factors. • Unique phenomena occurring at ultra-low temperatures were discussed. The frosting at ultra-low temperatures can cause significant degradation of the thermal performance of heat exchangers, which also leads to a decrease in the energy efficiency of air-source heat pumps. In this paper, the temperature terminologies for frosting were classified, and the frosting mechanism and frost properties were investigated from general-low to ultra-low temperatures. The dominant phase change mechanisms at general-low and ultra-low temperatures were condensation-freezing and desublimation, respectively. The frost layer growth mechanism at ultra-low temperatures can be classified into the formation of ice nuclei, growth of ice particles, and deposition of a frost layer in the initial stage of frosting. The frost morphology at ultra-low temperatures showed wisteria or shrub-shaped frost, which was not observed at general-low temperatures. Frost properties are determined depending on frosting factors such as cooling surface temperature, air temperature, absolute humidity, and air velocity, while the thermal conductivity of frost was determined by frost porosity. At ultra-low temperatures, some unusual phenomena were observed that were not observed at general-low temperatures. When the cooling surface temperature was at ultra-low temperatures, the fog was formed near the cooling surface along with the frost, and this fog was dominantly influenced by the frost surface temperature. In addition, unique phenomena such as thread-shaped frost and leading-edge frost concentrations were observed at ultra-low temperatures, and there was a clear difference in the frosting mechanism based on the temperature range. [ABSTRACT FROM AUTHOR]

Highlights: [•] A real-scale prototype house was built. [•] Coconut fibre filled ferrocement precast channel roof components present a thermal offset of 210min (3½h). [•] A lower thermal damping of 43% compared to ferrocement-only precast channel roof. [•] Coconut fibre limits the flow of heat at peak times where temperatures reach their highest values. [•] Ferrocement fibre filled precast channel roof components can bring thermal comfort. [Copyright &y& Elsevier]

• A gel electrolyte with safety and workability under harsh conditions is developed. • Dissociation of ion–solvent clusters enables the electrolyte to work at -20°C. • Low dielectric loss minimizes damages, enabling the electrolyte to work at 80°C. • Graphene oxide-doped polymers promote charring, rendering electrolytes inflammable. Safety and workability under harsh conditions are two of the major challenges for carbon-based electric double layer capacitors (EDLCs). Gel polymer electrolytes (GPEs), comprising a graphene oxide (GO)-decorated polymer blend of poly(acrylonitrile-co-methyl acrylate) and poly(ethylene glycol) integrated into a liquid electrolyte (LE), are developed. Under firing, the polymer entraps solvent molecules and the GO facilitates the charring of the GO-decorated GPE (GPEG), resulting in low flammability. The GO-polymer framework enhances the dissociation of counter-ion pairs and solvent−ion clusters to increase the ionic conductivity (to a value higher than that of the LE) and reduce the dielectric loss. The GPEG–EDLC outperforms EDLCs assembled using the LE and GO-free GPE with respect to capacitance, rate capability, and cycling stability. The high dissociation of the counter-ion pairs and solvent−ion clusters in the GPEG facilitates ion diffusion into the carbon micropores, thus improving the capacitive performance. The GPEG–EDLC presents excellent performance at −20°C due to the solvent−ion cluster dissociation. Its stable performance at 80°C is ascribable to the low dielectric loss, which minimizes the chemical damage to the system. Our study demonstrates the use of a GO-decorated dielectric polymer to address issues of safety and workability at extreme-temperatures. Dielectric gel electrolytes for safe charge storage from −20 to 80°C by double-layer capacitors [Display omitted]. [ABSTRACT FROM AUTHOR]

Abstract: In this work a batch of MEMS-based vibration energy harvesters consisting of a silicon/PZT thick film ntilever with integrated proof mass is characterized. The purpose of a vibration energy harvester is to convert low grade vibrations to useful electrical power. Optimally, the natural frequency of the harvester should match the frequency of he ambient vibration. The first step to achieve this is to evaluate the uniformity of the fabricated harvesters and nderstand the effects of temperature on the harvesters during operation. Therefore, the uniformity of 40 energy harvesters from one wafer has been evaluated. Thereafter the performance of the energy harvesters operating at emperatures between -30°C to 100°C was measured. [Copyright &y& Elsevier]

Abstract: Environmental temperature is known to correlate with schizophrenia, but little is known about the association with changes in temperature. This 12-year study aimed to evaluate the relationship between the mean daily range of ambient temperature and schizophrenia admissions in a national cohort of psychiatric inpatients in Taiwan. Meteorological data provided by the Central Weather Bureau of Taiwan were interpolated to create representative estimates. Psychiatric inpatient admissions in all hospitals with medical services enrolled in the current health care insurance system were retrieved from the 1996–2007 Psychiatric Inpatient Medical Claim dataset of the National Health Insurance Research Database. Generalized linear models with Poisson distributions were used to analyze the impact of mean diurnal change of temperature on schizophrenia admissions, controlling for internal correlations and demographic covariates. The daily temperature range varied between 1.7°C and 12.1°C (1st to 99th percentile). The relative risk of schizophrenia admission was significantly increased at a temperature range of 3.2°C (10th percentile), and the maximum was at 12.1°C (99th percentile); however, no such association was found with schizoaffective disorder. When restricted to the capital and largest city, the effects of temperature range were prominent and may correlate with temperature itself. The joint effect of temperature and temperature range was associated with elevated risk, particularly at cooler temperatures. A positive correlation was found between increasing temperature range and schizophrenia admissions. The increase in morbidity at high percentiles suggests that the increasing dynamics of temperature range are a valid reflection of risk, highlighting the need for precautionary action. [Copyright &y& Elsevier]

Abstract: The agricultural sector is probably the one that will suffer most directly from the climatic variations expected at the global level. In particular, the analysis of the changes expected in water availability and demand is fundamental in order to correctly establish both the present water resource management and the definition of new strategies. In this paper the time series of some climatic and agro-climatic indices in the Region of Umbria (Central Italy) have been analyzed with the aim of finding signs of climate changes and identifying the potential impacts on the agricultural water balance. The aforesaid indices include the precipitation, the mean maximum and minimum temperatures (Tmin, Tmax), the mean temperature range (ΔT), the reference evapotranspiration (ET0) and two drought indices, Standardized Precipitation Index (SPI) and Standardized Deficit Index (SDI, based on the difference between ET0 and precipitation). These indices were analyzed with reference to different periods (in particular the average growing and irrigation seasons). Furthermore, more specific information was obtained by analyzing the simulated water requirement (CWR) and evapotranspiration deficit (ED) of two typical annual crops (corn and sunflower). The time series of the indices were quantified for 38 stations in the region and they were then analyzed with non-parametric tests both at single sites and at the regional level. The tendencies in cumulated precipitation are generally decreasing (particularly during the wet period) and they are also characterized by a defined spatial pattern. The rainfall reduction during the irrigation season, although less widespread, could have the most important practical consequences. The significant trends detected for both the Tmax and Tmin are mainly positive, and they are more evident for Tmin, often resulting in a reduction of ΔT. ET0 shows a prevailing stationary condition due to the counteracting effects of the prevalent reduction observed for the ΔT and the increment of the mean temperature. At any rate, with reference to the irrigation season, ET0 trends are mainly positive. The results obtained for SPI and SDI are in accordance with the tendencies of non-standardized indices with an expectation of extreme drought event occurrence doubled or even tripled over a 30-year time span. Finally, the analysis of the CWR for corn and the ED for sunflower shows a relevant presence of significant positive trends whose impacts can be estimated in respective mean increments of about 23% and 44% over a 50-year time span. [Copyright &y& Elsevier]

Abstract: Several new electrode materials and electrolyte additives have been tested at Yardney in various combinations in order to improve the performance of LIB at elevated temperature and to extend the calendar life performance. The cell cycling results with new electrode/additive combinations were compared to the lithium-ion systems that normally work well at low temperatures. The goal of this effort was to enhance the cells’ cyclability at elevated temperature (70°C) without losing the performance at −20°C. [Copyright &y& Elsevier]

An analytical method has been developed to quantitize tar, liquids and gaseous products resulting from the flash pyrolysis of sub-bituminous Makarwal coal. The method involves the thermal decomposition of 200mg of 85-mesh size coal at 690°C under the flow of nitrogen using Shimadzu PYR-2A open tubular pyrolyzer. The resulting tar and liquid fractions were separated using two traps at the exit of the pyrolyzer while the gaseous products leaving the traps were on line injected to gas chromatograph equipped with porapak Q column and flame ionization detector for the analysis. Effect of demineralization on the yields of products was investigated by treating raw samples with 2M HCl. Removal of inherent minerals from coal by acid wash decreased the yield of total volatiles indicating catalytic properties of mineral under the condition used in present study. The influence of pyrolysis temperature on the yield of pyrolysates and hydrocarbon gases, resulting from raw coal samples, was studied over the temperature range of 500–770°C. [Copyright &y& Elsevier]

Microencapsulated phase change material (MPCM) slurries are energy-carrier fluids. Their latent heat utilization has been investigated by a new method based on the temperature properties of the phase-change fluid, in which match of the working and phase-change temperature ranges is considered. Based on the working-temperature range (3–15 °C) in heat-exchange circulation, the dynamic heat-transfer characteristics and utilization of the MPCM slurry with the core material n -docosane (C 22 H 46) are discussed. The experimental results indicate that the effects of the stirring rate and flow rate on the dynamic heat-transfer characteristics are similar to those of water, and they have little influence on utilization of the 10% MPCM slurry, whereas the corresponding effect of the concentration is relatively large. When investigating the effect of the concentration, it was found that a low phase-change ratio suppressed movement of the phase-change-temperature range owing to the residual solid core material acting as a crystal nucleus, while the heat-transfer performance and latent heat utilization of the MPCM slurry suppressed each other. The 10% MPCM slurry is the most suitable energy carrier fluid, but supercooling still needs to be resolved. The experimental results provide a reference for practical efficient application of MPCM slurries as energy carrier fluids. • Matching analysis of the working and phase-change temperature ranges used to evaluate MPCM slurry utilization. • Apparent specific heat capacity of the MPCM slurry measured in static and dynamic tests. • Heat-exchange circulation used to obtain the dynamic heat-transfer characteristics. • MPCM slurry's latent-heat utilization and heat-transfer coefficient are mutually restricted. • Residual solid core material is conducive to eliminating supercooling. [ABSTRACT FROM AUTHOR]

Despite the crucial role of herbivory in shaping community assembly, our understanding on biogeographical patterns of herbivory on seagrasses is limited compared to that on terrestrial plants. In particular, the drivers of such patterns remain largely unexplored. Here, we used a comparative-experimental approach in Cymodocea nodosa meadows, across all possible climate types within the seagrass distribution, 2000 km and 13° of latitude in two ocean basins, to investigate biogeographical variation in seagrass herbivory intensity and their drivers during July 2014. Particularly, the density and richness of herbivores and their food resources, seagrass size, carbon and nitrogen content, as well as latitude, sea surface temperature, salinity, chlorophyll, and sediment grain size, were tested as potential drivers. We found that shallow meadows can be subjected to intense herbivory, with variation in herbivory largely explained by fish density, seagrass size, and annual sea temperature range. The herbivorous fish density was the most important determinant of such variation, with the dominant seagrass consumer, the fish Sarpa salpa , absent at meadows from regions with low herbivory. In temperate regions where herbivorous fish are present, annual temperature ranges drive an intense summer herbivory, which is likely mediated not only by increased herbivore metabolic demands at higher temperatures, but also by higher fish densities. Invertebrate grazing (mainly by sea urchins, isopods, amphipods, and/or gastropods) was the dominant leaf herbivory in some temperate meadows, with grazing variation mainly influenced by seagrass shoot size. At the subtropical region (under reduced annual temperature range), lower shoot densities and seagrass nitrogen contents contributed to explain the almost null herbivory. We evidenced the combined influence of drivers acting at geographic (region) and local (meadow) scales, the understanding of which is critical for a clear prediction of variation in seagrass herbivory intensity across biogeographical regions. Unlabelled Image • We examine drivers of seagrass herbivory across 2000 km and 13° of latitude in 2 ocean basins. • Fish density, seagrass size, and sea temperature range mostly determine herbivory intensity. • In temperate regions, high summer temperatures drive an intense herbivory via greater fish density and metabolic demands. • Almost no herbivory at the subtropic likely due to lower seagrass density and N content [ABSTRACT FROM AUTHOR]

High-resolution clay mineral and δ 18O carb analyses have been performed on three sections of Valanginian age (Early Cretaceous), from northwestern (~20–30°N) and southern (~53°S) Tethyan realms. The data have been integrated in a large set of published mineralogical (clays), and geochemical (δ 18O carb , δ 18O bivalve, δ 18O lenticulina , δ 18O belemnite , and TEX 86) data from 17 sections, situated between ~45°N and ~53°S. Based on this data set, we provide new insights into Valanginian climate conditions from a wide range of palaeolatitudes. We highlight climate trends within specific areas and identify main climate belts. In the Proto-North Atlantic realm (~15–17°N) large amounts of smectite together with the occurrence of palygorskite testify for a semi-arid climate belt throughout the Valanginian. Significant variations in kaolinite content in the northwestern Tethyan realm (~20 to 30°N) suggest that this realm has been more sensitive to changes in hydrological cycling and subsequent erosion and runoff processes during the early to early–late Valanginian transition interval. This time interval, that is coincident with the pronounced positive and globally recognized carbon isotope excursion (CIE; the Weissert episode), documents the wet conditions of a humid subtropical climate belt. Temperature ranges derived from δ 18O records suggest climate warming by about 3–5±0.9°C in the northern hemisphere, during the Weissert episode. This is followed by a global cooling of about ca. 1–5±0.9°C in both hemispheres, during the late Valanginian. We postulate that these patterns were due to interplays between tectonic and orbital factors, which have controlled the distribution of regional palaeoclimate belts during the Valanginian. The semi-arid belt expressed in the Proto North Atlantic realm has probably been induced by its specific palaeogeographic configuration and the existence of isolated basins, which were each characterized by strong and continuous thermohaline circulation. An eccentricity paced monsoon-like system might have played a significant role in maintaining the subtropical belt around the northwestern Tethyan realm, up to the mid latitudes (~35–45°N). Superimposed on these regional processes, a widespread magmatic pulse in Paraná-Etendeka volcanic activity might have stimulated greenhouse conditions, impacting marine biota and favouring the development of a dense vegetation cover on the continent. An increase in sedimentary burial of 13C depleted organic carbon on the continents may have contributed to the progressive global positive carbon isotope excursion. In the medium term, it has also probably led to a significant decrease in atmospheric CO 2 , as testified by the global cooling recorded during the late Valanginian in both hemispheres and the probable concomitant extension of polar ice caps. [ABSTRACT FROM AUTHOR]