Extreme Low Temperature Research Articles

Interannual variation of the number of winter extreme low temperature days in southern China and influencing factors

The interannual variation of the number of winter extreme low temperature days (NELTD) in southern China from 1980 to 2019 is analyzed, and the individual and combined effects of the autumn sea surface temperature anomaly (SSTA) in the central equatorial Pacific and Siberian snow cover extent anomaly (SCEA) are investigated. The analysis shows that the anomalous atmospheric circulation in Eurasia is dominated by the meridional dipole pattern with the characteristic of “high north and low south” during the winter with large NELTD in southern China. The autumn SSTA in the central equatorial Pacific influences the winter NELTD mainly through the anomalous atmospheric circulation at the mid–low latitudes while the Siberian SCEA in October acts by affecting that at the mid–high latitudes. A cold SSTA is conducive to strengthening the winter East Asian trough and subtropical jet, as well as abnormal northeasterly wind in most parts of southern China. However, the central equatorial Pacific SSTA has a limited influence on the Ural ridge, polar front jet, and Siberian High at the mid–high latitudes. On the other hand, the Siberian SCEA could result in anomalous atmospheric circulation at the mid–high latitudes, which has a strengthening and supplementing effect on that of SSTA in the central equatorial Pacific. During the winter following the negative SCEA in October, the Ural ridge and Siberian High are strengthened while the polar front jet is weakened. The anomalous atmospheric circulation in Eurasia is dominated by a meridional dipole pattern of “high north and low south”. The comparative analysis reveals that both SSTA and SCEA play an important role in the NELTD in southern China, but they are independent factors and act in different ways. Therefore, the combined effect of autumn SSTA in the central equatorial Pacific and Siberian SCEA could contribute to the prediction of the winter NELTD in southern China.

Disaster process-based spatiotemporal characteristics of apricot frost in the warm temperate zone (WTZ), China.

Frost stress is a major environmental factor that limits apricot growth in the warm temperate zone (WTZ) of China, and is always triggered by extreme low temperature weather processes. In this study, the characteristics of the apricot frost processes f(D, Tcum), which were identified from historical disaster representation, were analyzed and apricot frost evaluation indicators were developed, thus facilitating the process-based assessment and spatiotemporal analysis of apricot frost processes. Periods of low temperature that persist for 1~2, 3, and ≥4 days (i.e., duration days, D) provide the initial identification indicator for light, moderate, and severe apricot frost. The threshold ranges for Tcum are 0~3.9, 9.2~12.0, and >16.2 for D values of 1~2, 3, and ≥4, respectively. The northwest of the WTZ is dominated by apricot frost, with approximately 80% of apricot frost being light, followed by moderate and severe. Regional apricot frost exhibited a significant decreasing trend over the last four decades. A total of 29.65% of stations, which were mainly located in the northwest and middle parts of the study region, detected an increasing trend in apricot frost. The results provide technical support for targeted apricot frost level detection, and the process-based spatiotemporal characteristics of apricot frost can provide basic information for the prevention and mitigation of apricot frost.

The Impact of Extreme Temperatures on Grain Production in the Huaihe River Basin

The Huaihe River Basin is an important major grain producing area in China, maintaining the stability of grain output is of great significance to food security. However, with global warming, the frequency of extreme temperature events has increased, and the frequent meteorological disasters have brought great challenges to the stable supply of food production. In this paper, the impact of extreme temperature on grain production in the Huaihe River Basin was analyzed by using the daily temperature and agricultural production related data of 28 prefecture-level cities in the Huaihe River Ecological Economic Belt from 2001 to 2020. The following conclusions are drawn: 1) The influence coefficient of extreme high temperature on grain production in the Huaihe River Basin is -0.021, extreme low temperature has no significant impact on food production. 2) The effects of extreme temperature on food production in different regions in the river basin were heterogeneous, but the overall impact was negative. The influence coefficients of extremely high temperature days on the eastern region and Midwest region were -0.035 and -0.052, respectively, while the influence coefficients of extremely low temperature days on the eastern region were -0.413. The results showed that the increase in the number of extremely high temperature days would reduce production in the eastern region andMidwest region of the basin, while the northern region was not significantly affected by extreme heat. The increase in the number of extremely low temperature days will reduce grain production in the eastern region, and the impact on the Midwest region and the northern region will not be significant. Based on the above conclusions, three suggestions are put forward to maintain the safety of food production in the Huaihe River Basin: 1) enhance the ability to detect climate change in the basin; 2) Protect the stability of grain cultivated land in the river basin; 3) Innovative breeding of climate-resilient food crop seeds.

Relationship between extensive and persistent extreme cold events in China and stratospheric circulation anomalies

This study examines the relationship between the extensive and persistent extreme cold events (EPECEs) in China and geopotential height anomalies in the stratosphere using daily mean fields of outgoing long wave radiation (OLR) produced by the NCAR and daily atmospheric circulations produced by the NCEP/NCAR. The OLR composite analysis for the EPECE in China demonstrates that the negative OLR height anomalies (cold air) originated from Siberia influence China progressively from north to south. The largest negative OLR height anomaly (cooling event) occurs in the region to the north of the Nanling Mountains. This suggests that the OLR height anomalies can be used to represent the temporal and spatial characteristics of extreme low temperatures and cold air activities in winter in China. The composite analysis of large-scale atmospheric circulations during the EPECE reveals characteristic evolutions of stratospheric and tropospheric circulations during the extreme cold event. We demonstrate the important role of atmospheric circulation anomalies in the outbreak and dissipation of the EPECE in China. We also demonstrate that significant perturbations in the stratospheric circulation occur more than 10 days prior to the outbreak of the EPECE, with positive height anomalies in the Arctic stratosphere. These positive anomalies propagate downward from the stratosphere and affect the formation and development of the high pressure ridge in the middle troposphere over the Ural Mountains. Significant changes also occur in the atmospheric circulation in the mid-latitude stratosphere. These changes propagate downward from the stratosphere and strengthen the low pressure trough in the troposphere in the region to the east of Lake Balkhash and Lake Baikal. Therefore, the changes in the stratospheric circulation during the EPECE in China occur prior to changes in the tropospheric circulation and are very useful for predicting extreme wintertime cold temperatures in China.

Possible Linkage Between Winter Extreme Low Temperature Over Western‐Central China and Autumn Sea Ice Loss

AbstractBased on reanalysis datasets and sea‐ice sensitivity experiments, this study has pointed out that the autumn sea ice loss in East Siberian‐Chukchi‐Beaufort (EsCB) Seas significantly increases the frequency of winter extreme low temperature over western‐central China. Autumn sea ice loss warms the troposphere and generates anticyclonic anomaly over the Arctic region 1 month later. Under the effects of synoptic eddy‐mean flow interaction and anomalous upward propagated planetary wave 2, the Arctic anticyclonic anomaly strengthens and develops toward Greenland‐Northern Europe, accompanied by a weakened stratospheric polar vortex. In winter, following intra‐seasonal downward propagation of stratospheric anomalies, the Northern European positive geopotential height anomalies enhance and expand downstream within 7 days, favoring Arctic cold air east of Novaya Zemlya southward (the hyperpolar path) accumulating in Siberia around Lake Baikal. In the subsequent 2–3 days, these cold anomalies rapidly intrude western‐central China and induce abrupt sharp cooling, thus more frequent extreme low temperature there. In contrast, the role of autumn Barents‐Kara (BK) sea ice loss exhibits quite different features, mainly favoring northwestern, northeastern and eastern China to experience increased frequency of extreme low temperature in winter.

Influence of Land–Atmosphere Coupling on Low Temperature Extremes Over Southern Eurasia

AbstractLand–atmosphere coupling is a crucial factor influencing extreme weather and climate. Based on the ERA5‐Land reanalysis data set and sensitivity experiments with the CESM1.2.2 model, this study investigated the possible impacts of land–atmosphere coupling on low temperature extremes (LTEs) during fall and winter over southern Eurasia (SEA). The results suggested that LTEs show evident interdecadal variations in recent 60 years (1958–2017) and exhibit significant positive correlations with soil moisture anomalies based on the ERA5‐Land data set. Numerical simulations (the control run and sensitivity run with prescribed climatological soil moisture) isolated the effects of soil moisture‐related land surface processes and demonstrated that land–atmosphere coupling explains around 70% of temperature variability, increases the near‐surface air temperature by 0.81 K, and favors the reduction of LTEs by 8.20 d·yr−1. In the perturbation scenarios, the impacts of coupling on the frequency and spatial coverage of LTEs are more prominent. Further analysis revealed that the thermal cooling anomalies induced by the coupling could alter the atmospheric circulation, thereby affecting the frequency and intensity of LTEs. When the land–atmosphere interactions are weakened, the surface latent heat flux increases accompanied by intense evapotranspiration, while the sensible heat flux and net infrared radiation decrease. Land surface cooling is apparent, and it weakens with increasing altitude, along with geopotential height anomalies that are positive in the lower troposphere and weaker at higher altitudes. The northeasterly wind anomalies over the East European Plain facilitate the development of cold advection, providing a favorable circulation background for the generation of LTEs over SEA.

Adaptation measures for asphalt pavements to climate change in China

Climate change is impacting on pavement infrastructure in China. To eliminate the issues of asphalt freeway pavement caused by climate change, this study evaluated the temperature change in China from 2020 to 2059. The related pavement issues include rutting, fatigue life, and thermal crack caused by climate change are assessed based on the prediction models incorporated with the predicted future climate. The potential future distresses were analyzed, quantified, and cataloged, then the effectiveness of optional adaptation measures included adjustment of structure thickness, dynamic modulus, and creep stiffness were analyzed. Finally, a method to select and quantify the adaptation measures was developed based on the effectiveness analysis of adaptation measures. The major findings of this study are listed below: (1) Temperature rise is the general trend, rutting and fatigue issue is typical issue caused by climate change. (2) Extreme low temperature issue would occur more severe for some area in future, up to 35% of pavement would have more severe thermal crack issue caused by climate change in 2050s. (3) Six quantified adaptation measures were suggested to solve these two types of issues caused by climate change.

Spatial–Temporal Distribution Pattern of Ormosia hosiei in Sichuan under Different Climate Scenarios

Ormosia hosiei is an endemic plant in China listed as a national grade II key protected wild plant with important scientific, economic, and cultural values. This study was designed to predict the potential suitable distribution areas for O. hosiei under current and future climate change and to provide a reference to enhance the species’ conservation and utilization. Based on the actual geographical locations of O. hosiei in Sichuan, we applied two species distribution models (BIOCLIM and DOMAIN) to predict its current and future potential suitable areas and future change patterns. We also analyzed the major climatic variables limiting its geographical distribution with principal component analysis. The results indicated that O. hosiei was mainly distributed in the eastern region of Sichuan and concentrated in the middle subtropical climate zone at relatively low elevations. The principal component analysis identified two critical factors representing temperature and moisture. The temperature was the most critical factor limiting O. hosiei distribution in Sichuan, especially the effect of extreme low temperatures. Both models’ simulation results of potential suitable areas under the current climate scenario showed that the excellent suitable habitat was consistent with the current actual distribution, remaining in the eastern region of Sichuan. Under the future climate scenario with doubled CO2 concentration (2100), both models predicted a sharp decrease in the areas of excellent and very high suitable habitats. The findings can inform strategies and guidelines for O. hosiei research, conservation, nursery production, and cultivation in Sichuan.

Extreme low apparent temperature forecasting for early warning of mortality by data-driven deep learning

Abrupt changes in environmental temperature, wind and humidity can lead to great threats to human life safety. The Gansu marathon disaster of China highlights the importance of early warning of hypothermia from extremely low appar-ent temperature (AT). Here a deep convolutional neural network model together with a statistical downscaling framework is developed to forecast environmental factors for 1 to 12 h in advance to evaluate the effectiveness of deep learning for AT prediction at 1 km resolution. The experiments use data for temperature, wind speed and relative humidity in ERA-5 and the results show that the developed deep learning model can predict the upcoming extreme low temperature AT event in the Gansu marathon region several hours in advance with better accuracy than climatological and persistence forecast-ing methods. The hypothermia time estimated by the deep learning method with a heat loss model agrees well with the observed estimation at 3-hour lead. Therefore, the developed deep learning forecasting method is effective for short-term AT prediction and hypothermia warnings at local areas.

Atrazine decontamination by a newly screened psychrotroph Paenarthrobacter sp. KN0901 in an aquatic system: Metabolic pathway, kinetics, and hydroponics experiment

Atrazine residues running off the fields and entering water resources are a major threat to food security and the ecosystem. In this study, a psychrotrophic functional strain named KN0901 to remove atrazine residues was screened. KN0901 could degrade 30 mg·L−1 atrazine in 4 days at 15ºC with 105 CFU·mL−1 incubation. The phylogenetic results showed KN0901 belonged to Paenarthrobacter sp. PCR results showed that the functional genes consist of trzN, atzB, and atzC, suggesting atrazine was transformed to cyanuric acid by KN0901. KN0901 could degrade atrazine without adding exogenous carbon and nitrogen sources. What’s more, KN0901 could tolerate extreme low temperature (5ºC) and high atrazine concentration (100 mg·L−1). When growth and degradation curves were compared, the results indicated the length of lag time showed significant correlation to atrazine degradation rate. The hydroponic experiments showed that the toxicity of atrazine was significantly reduced with KN0901 treatment. The study provided an effective, economic, and eco-friendly bioremediation measure to address atrazine contamination.

Effects of sowing patterns on nitrogen utilization and yield formation of winter wheat in the western Huang-Huai-Hai region.

To examine the differences of three improved sowing methods in winter wheat yield and nitrogen efficiency and reveal the characteristics responsible for such differences, we conducted field experiments in the Jinnan area of the western Huang-Huai-Hai wheat region for three consecutive seasons from 2016 to 2019. The three improved sowing methods were wide space sowing (WSS), furrow sowing in moisture soil (FS), and three-dimensional uniform sowing (TDUS), with conventional drilling sowing (CDS) as the control. The results showed that meteorological factors such as accumulated temperature, solar radiation, and precipitation in the growing seasons from 2016 to 2019 showed great intra- and inter-annual variations. Compared with CDS, the improved sowing methods (WSS, FS, and TDUS) enhanced spike number per unit area and increased grain yield in three growing seasons by 18.3%-55.5%, 8.6%-22.2%, and 10.9%-39.5%, respectively. The three methods increased nitrogen uptake efficiency (NEup) by 5.8%-57.1%, pre-flowering nitrogen transfer ratio (Np/Nt) by 3.0%-15.3%, and nitrogen efficiency by 7.9%-35.7%, respectively. We developed a structural equation model (SEM) by integrating meteorological factors and experimental variables. The results showed that the three improved sowing methods could reduce the effects of extreme low temperature on wheat plant population, increase NEup and Np/Nt, and provide sufficient nitrogen supply to the grains of high-spike number wheat population for high yield and high nitrogen efficiency. In summary, our results demonstrated that WSS, FS, and TDUS all improved NEup and Np/Nt in the 2016-2017 season when meteorological conditions were favorable for wheat growth, and enhanced yield components with high SN, leading to high yield and high nitrogen efficiency. In contrast, in both 2017-2018 and 2018-2019 seasons with extremely low temperature and uneven distribution of meteorological conditions, WSS had a higher number of tillers at the jointing stage and enhanced pre-flowering nitrogen uptake and translocation, whereas TDUS had a relatively stable nitrogen uptake rate, leading to a stable grain yield.

Examining the Relationship Between Extreme Temperature, Microclimate Indicators, and Gestational Diabetes Mellitus in Pregnant Women Living in Southern California.

We utilized 2008-2018 data for pregnant women from Kaiser Permanente Southern California electronic health records. GDM screening occurred between 24 and 28 gestational weeks for most women using the Carpenter-Coustan criteria or the International Association of Diabetes and Pregnancy Study Groups criteria. Daily maximum, minimum, and mean temperature data were linked to participants' residential address. We utilized distributed lag models, which assessed the lag from the first to the corresponding week, with logistic regression models to examine the exposure-lag-response associations between the 12 weekly extreme temperature exposures and GDM risk. We used the relative risk due to interaction (RERI) to estimate the additive modification of microclimate indicators on the relation between extreme temperature and GDM risk. GDM risks increased with extreme low temperature during gestational weeks 20--24 and with extreme high temperature at weeks 11-16. Microclimate indicators modified the influence of extreme temperatures on GDM risk. For example, there were positive RERIs for high-temperature extremes and less greenness, and a negative RERI for low-temperature extremes and increased impervious surface percentage. Susceptibility windows to extreme temperatures during pregnancy were observed. Modifiable microclimate indicators were identified that may attenuate temperature exposures during these windows, which could in turn reduce the health burden from GDM.

New genotyping rescues old phenotypes: beneficial traits in Heterorhabditis bacteriophora wild type material and association to single nucleotide polymorphisms

Summary The entomopathogenic nematode (EPN), Heterorhabditis bacteriophora, is a biocontrol agent with almost world-wide distribution, thus providing a huge source of biodiversity available for exploitation in breeding programmes to improve beneficial traits. For management of economically important insect pests, the nematode is mass-produced in liquid culture, formulated with inert carriers, and transported under controlled temperature conditions to maintain its quality. The biocontrol potential of nematode materials is defined by their genetic background. Previous reports have assessed the phenotypic plasticity of H. bacteriophora. Major beneficial traits are field efficacy influenced by their virulence, longevity and field persistence and tolerance to abiotic stresses like oxidative stress, desiccation and extreme low and high temperatures. For several of these traits high heritability values (h2) have been reported, providing a platform for trait improvement by selection. Modern breeding uses molecular markers to track beneficial traits. Recent studies reported hundreds of single nucleotide polymorphisms (SNPs) in H. bacteriophora. This investigation revived a large set of cryopreserved wild types, hybrids and phenotyped materials of H. bacteriophora. Additional phenotypic data on the virulence (LC50) of H. bacteriophora strains against mealworm (Tenebrio molitor) were produced ranging from 1.4 ± 0.3 to 8.0 ± 3.6 nematodes per insect. Markers linked to beneficial traits were used for a comprehensive genotype analysis transferring reported SNP sequence information into the multiplex platform SeqSNP. Specific alleles associated to beneficial traits were identified and 65 materials were classified for the presence of relevant SNPs associated to beneficial traits. This information provides a valuable platform for exploitation of the nematode’s biodiversity for future breeding and selection approaches.

Significant colony differences in thermal tolerances and decoupling of high and low critical temperatures in the army ant Eciton burchellii parvispinum

Abstract Differences in behaviour and physiology among social insect colonies provide opportunities for evolutionary responses to environmental selection. Colony differences in thermal physiology can indicate potential for social insect populations to accommodate temperature extremes and determine how populations will respond to changing climates. We tested whether army ant (Eciton burchellii parvispinum) colonies differed in their distributions of worker tolerances of extreme low temperatures (CTmin) and extreme high temperatures (CTmax). We sampled workers across a range of body sizes in each colony, and we collected data from colonies at both warmer low elevation sites and cooler high elevation sites. Colonies differed significantly in the distributions of both CTmin and CTmax; colony mean CTmin and CTmax were not correlated. The colony differences were not associated with worker body size variation. Some thermal physiology differences were associated with local climates: colonies from warmer lower elevation sites had significantly higher CTmin and higher CTmax, but much of the inter‐colony variation was unexplained. If significant colony variation in thermal physiology is associated with genetic differences, thermal environments could drive evolutionary changes in thermal physiology.

Renewable resource-derived elastomer vitrimer and its sustainable manufacturing and application in extreme environmental conditions

The development of biomass (e.g., lignin, cellulose or vegetable oil)-based reversibly dynamic covalent cross-linked elastomer vitrimer materials is a novel approach to address issues related to the recycling of waste cross-linked elastomer material. The primary questions discussed are about how to design chemically recycled biomass-derived cross-linked elastomer vitrimer materials, what are the potential challenges in sustainable manufacturing of cross-linked renewable resources derived elastomer vitrimer materials, and what are their potential advanced applications under extreme environmental conditions, such as extreme low or high temperature and irradiated environments.

PO-04-041 EFFICACY OF BALLOON EXPANDABLE EXTREME-LOW TEMPERATURE "XLT" VENTRICULAR EPICARDIAL CRYOABLATION: A PRE-CLINICAL DOSE RANGING STUDY

Lack of transmural lesion formation with catheter or surgical ablation for ventricular tachycardia (VT) can be an important determinant of arrhythmia recurrence. The aim of this study was to evaluate the feasibility and efficacy of a novel balloon expandable extreme-low temperature (XLT) cryoablation device for epicardial ventricular ablation. A total of six healthy Yorkshire swine (63 ± 6 kg) underwent surgical epicardial access. Four-to-five right (RV) and left (LV) ventricular epicardial targets were identified: anterior (1-2), lateral (1-2), summit (1-2). Ablation was performed with the novel 'XLT-cryo' device (HeartPad®Mini, Corfigo, Montclair, NJ), a balloon-expandable epicardial device that circulates extremely cold helium (∼ -253C) at a high flow rate through a flat pad with dimensions of ∼15 x 15mm. It is mounted onto the surface of an ∼30mm insulation balloon with blunted ends for fixation and parietal pericardial protection. At the end of each timed ablation, a thaw cycle was initiated to warm the device and allow repositioning to the next target. Ablation lesion size was measured using TTC staining. A total of 27 epicardial lesions were created (RV: n=2; LV: n = 25). The average lesion depth increased with time and reached complete transmurality with a plateau at 1 minute (time [T; sec] and mean depth±stdv [mm]; T15=11±0.5, T30=12±1, T60=15±1, T120=16±0.5, T240=17±0.5; Figure). Lesion transmurality was achieved in all lesions with ablation time ≥2 min. Lesion geometry was similar across different RV/LV locations, including the LV summit. Ventricular fibrillation (which is common in Yorkshire swine) occurred during/following 3 applications out of 27. Our results indicate that epicardial cryoablation using the novel balloon expandable HeartPad® device with extremely low temperature applications can efficiently produce transmural ventricular lesions in different epicardial locations. This technology holds potential for both surgical and catheter-based VT ablation in humans.

The observed features and some possible reasons of annual temperature extremes over Beijing‐Tianjin‐Hebei region for a century long‐term based on newly constructed daily observations

AbstractThe observation facts of trend and variability are estimated for a century‐long timescale, as well as some possible attributions affecting temperature extremes over Beijing‐Tianjin‐Hebei region. In this paper, the new constructed daily maximum and minimum temperature series during the last 100 years in situ stations of Beijing, Tianjin and Baoding city are used, and two 30‐year baseline climatology of 1961–1990 and 1980–2010 are both used in calculating extreme temperature events. The results indicate that there are long‐lasting, frequent and serious extreme warming over Beijing‐Tianjin‐Hebei region, especially for extreme low temperature, with larger declining trends (at 5% significance) from 1981 to 2010 baseline than those from 1961 to 1990 baseline. And from a statistical perspective, El Niño decay years and surface sea temperature (SST) anomalies at some typical ocean regions of the Arabian Sea and the Bengal Bay on the northern Indian Ocean, the Western Pacific and the Mid Atlantic, Southern Indian Ocean and around 45°–85°E, 68°–82°N on the southwest Arctic Ocean can be used as the warning signals denoting extreme warming over Beijing‐Tianjin‐Hebei region. Additionally, urbanization has a significant (at 5% significance) effect on extreme warming over Beijing‐Tianjin‐Hebei region since 1979, with 24.3% warming contribution for annual minimum temperature.

Tardigrade-inspired extremotolerant glycerogels

We developed extremotolerant glycerogels (GGs) with well-modulated polymer structures, functions, and properties, inspired by the tun formation of tardigrades. GGs comprising extreme protected intra- and intermolecular networks are obtained through a very slow structure building process, which includes the smooth replacement of water in predesigned hydrogels with glycerol and thermal annealing while retaining the structures and functions of the original hydrogels. Four different GGs are fabricated as proofs-of-concept using different crosslinkers and polymers. Although various polyol-based wide-temperature-tolerant gels fabricated by conventional methods fail to demonstrate stabilities at low and high temperature extremes simultaneously, the GGs fabricated by our bioinspired method exhibit long-term stability (approaching one month) over an extremely wide temperature range (−50–80 °C) and thermal-shock-absorption capabilities at 150 °C. Furthermore, our versatile method enables us to program GGs with wide ranges of stiffness, strength, stretchability, and toughness values and elasticity, plasticity, hysteresis, and self-recoverability capabilities. The self-weldability, electrical patternability, and applicability characteristics of the GGs as electrolytes and supercapacitors demonstrate their complex 3D designability and facile functionalization capability aspects. The various functional GGs developed through the proposed method are applicable for the design of diverse extremotolerant, flexible, and stretchable devices for biological, electrical/electronic, and soft robotics applications.

Flexible and Antifreezing Fiber-Shaped Solid-State Zinc-Ion Batteries with an Integrated Bonding Structure

Fiber-shaped solid-state zinc-ion battery (FZIB) is a promising candidate for wearable electronic devices, but challenges remain in terms of mechanical stability and low temperature tolerance. Herein, we design and fabricate a FZIB with an integrated device structure through effective incorporation of the active electrode materials with a carbon fiber rope (CFR) and a gel polymer electrolyte. The gel polymer electrolyte incorporated with ethylene glycol (EG) and graphene oxide (GO) endows the FZIB with a high Zn stripping/plating efficiency under extreme low temperature conditions. A high power density of 1.25 mW cm-1 and large energy density of 0.1752 mWh cm-1 are obtained. In addition, a high capacity retention of 91% after 2000 continuous bending cycles is achieved. Furthermore, the discharge capacity is fairly retained at more than 22% even at the low temperature of -20 °C. Toward practical applications, the FZIB integrated into textiles to power electronic products is demonstrated.

Intelligent sliding mode fault-tolerant control of aviation propulsion motor system based on adaptive chaotic gray wolf optimization

In order to solve the problem of motor fault caused by extreme low temperature and vibration in the high altitude of aviation propulsion motor, using the intelligent sliding mode fault-tolerant control, a speed controller based on variable exponential power reaching law and an extended sliding mode disturbance observer is designed; furthermore, the parameters are optimized by the adaptive chaotic gray wolf optimization algorithm. In addition, a second-order nonsingular terminal sliding mode observer and a frequency adaptive complex coefficient filter are designed. First, variable exponential power reaching law is helpful to eliminate the speed tracking error and buffeting for the speed controller, the external disturbance can be estimated and compensated using the extended sliding mode disturbance observer, and adaptive chaotic gray wolf optimization algorithm can enhance the accuracy of parameters. Second, for the sake of making the aviation propulsion motor run smoothly in the case of speed sensor fault, second-order nonsingular terminal sliding mode observer is designed to estimate the speed and position of aviation propulsion motor, and adaptive complex coefficient filter is designed to improve the estimation accuracy. Finally, based on MATLAB/Simulink simulation and STM32 motor series experiments, the effectiveness of the proposed observer and controller algorithm is verified.