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China is rich in hydropower resources, and mountain rivers have abundant water resources and huge development potential, which have a profound impact on the pattern of water resources allocation in China. As the main way of water resources and hydropower development, the construction of cascade hydropower stations, while meeting the requirements of water resources utilization for social development, has also brought adverse effects on river ecosystems. Therefore, the impact of the construction of cascade hydropower stations on mountainous river ecosystems, where the minimum ecological flow of rivers must be ensured and reviewed. In addition, this paper proposed the deficiencies and outlooks for cascade hydropower stations based on previous research results.

Adsorption heat pumps (AHPs) powered by low-grade waste heat or renewable energy can reduce electricity consumption and carbon emission.

Vegetation plays a vital role in the terrestrial ecosystem. Vegetation variations not only result from climatic and environmental change but also feed back to the climate through biogeochemical and biogeophysical processes. Previous studies have mainly focused on the influence of environmental factors on vegetation changes, but the interactions between vegetation and the prevalent environmental factors in the karst areas of southwestern China have been poorly understood. Based on remote sensing data, this study used trend analysis and Granger causality analysis to investigate vegetation trends, the driving factors, and their interactions during the period 2001 to 2021. In summary, we explored how these factors influenced vegetation growth and how vegetation changes fed back to produce ecosystems and environmental variations in southwestern China during this period. The results showed improvements in water conditions as well as a vegetation greening trend in most of the regions of southwestern China, together with a weakening trend of rocky desertification and an increasing trend of vegetation growth during the period. Both terrestrial water storage and vegetation growth in the energy-limited alpine regions are sensitive to temperature. Natural restoration is suggested in this area. Vegetation growth in the karst areas is sensitive to water stress-related variables due to the particular geological and soil characteristics. The bidirectional causality relationship between vegetation greening and the environment factors in many of these areas indicates that the vegetation changes can also significantly affect water balance and conditions. Ecological engineering projects are suggested in this area. The vegetation growth in the SC Basin, HN, HB, GD, and eastern GX is also sensitive to water stress, while these regions are vulnerable to waterlogging. This study helps to improve our understanding of ecosystem management and promote sustainable development in southwestern China.

Capturing formaldehydes (HCHO) from indoor air with porous adsorbents still faces challenges due to their low capacity and poor selectivity. Metal-organic frameworks (MOFs) with tunable pore properties were regarded as promising adsorbents for HCHO removal. However, the water presence in humid air heavily influences the formaldehyde capture performance due to the competition adsorption. To find suitable MOFs for formaldehyde capture and explore the relationship between MOFs structure and performance both in dry air and humid air, we performed grand canonical Monte Carlo (GCMC) molecular simulations to obtain working capacity and selectivity that evaluated the HCHO capture performance of MOFs without humidity. The results reveal that small pore size (~5 Å) and moderate heat of adsorption (40–50 kJ/mol) are favored for HCHO capture without water. It was found that the structure with a 3D cage instead of a 2D channel benefits the HCHO adsorption. Atoms in these high-performing MOFs should possess relatively small charges, and large Lennard-jones parameters were also preferred. Furthermore, it was indicated that Henry’s constant (KH) can reflect the HCHO adsorption performance without humidity, in which the optimal range is 10−2–101. Hence, Henry’s constant selectivity of HCHO over water (SKH HCHO/H2O) and HCHO over mixture components (H2O, N2, and O2) was obtained to screen MOFs at an 80% humidity condition. It was suggested that SKH for the mixture component overestimates the influence of N2 and O2, in which the top structures absorb a quantity of water in GCMC simulation, while SKH HCHO/H2O can efficiently find high-performing MOFs for HCHO capture at humidity in low adsorption pressure. The ECATAT found in this work has 0.64 mol/kg working capacity, and barely adsorbs water during 0–1 bar, which is the promising candidate MOF for HCHO capture.

Late-onset hypogonadism (LOH) is a syndrome in middle-aged and elderly men caused by age-related testosterone deficiency. Age-related change of total testosterone (TT) of Asian males is different from Caucasian population, suggesting difference for LOH identification in Asians. A nationwide cross-sectional study involving six centers in China was conducted. Totally 6296 men aged 40-79 were recruited. After exclusions 5980 men were left for analyses. The serum TT level, was neither decreased with aging nor correlated with most hypogonadal symptoms. Instead, ten hypogonadal symptoms were found to be significantly correlated with free testosterone and testosterone secretion index, thus were chosen to form a concise scale. Further analysis identified a level of free testosterone

Background Liver cancer (LC) is the sixth most common cancer and the second leading cause of cancer mortality worldwide, and its incidence rate is high in China. Methods In this study, we aimed to investigate the contribution of MIR137HG (MIR137 Host Gene) polymorphisms to LC risk in a case-control study with 432 LC patients and 430 healthy controls. A logistic recession model was used to evaluate the effects of candidate single nucleotide polymorphisms (SNPs) on LC risk. HaploReg v 4.1 database was conducted to predict the potential functionality of SNPs. Results The results revealed that rs17371457 and rs7554283 in the MIR137HG gene were correlated with an enhanced LC risk under the allele (P = 0.001 and P = 0.043, respectively) and genetic models (P 55 years (P < 0.05); rs17371457 was related to higher LC risk in males (P < 0.05). Similarly, the haplotype AG constituted by rs12333983 and rs3735451 significantly increased LC risk in Chinese Li population (P = 0.043). Six SNPs distributed in MIR137HG were successfully predicted as regulatory SNPs with different biological functions. Conclusion Our research firstly showed that MIR137HG gene polymorphisms were implicated in LC susceptibility among Chinese Li population.

Understanding the changes in regional droughts is important for promoting overall sustainable development. However, the spatiotemporal dynamics of soil droughts in Guangxi under the background of global warming and regional vegetation restoration have not been studied extensively, and the potential causes are scarcely understood. Here, using TerraClimate soil moisture data, we constructed a monthly standardized soil moisture index (SSMI), analyzed the seasonal and annual spatiotemporal distribution of droughts from the perspective of soil moisture, and studied past soil drought events in Guangxi. Migration methods of drought centroid, trend analysis, and principal component decomposition were used. In the interannual dynamics, the overall SSMI increased, indicating that the soil drought situation was gradually alleviated in Guangxi. Further, the frequency of extreme and severe droughts decreased with time, mainly in autumn and winter. During early drought stages, the migration path was short, which extended as the droughts progressed. Ocean temperature and soil moisture were strongly correlated, indicating that abnormal ocean surface temperature may drive soil moisture. This study provides scientific guidance for the early warning, prevention, and mitigation of losses associated with soil droughts in Guangxi and serves as valuable reference for understanding the impacts of large-scale climate anomalies on soil moisture.

High latent heat of phase change materials (PCM) has made them as one of the most potential materials in many advanced applications. However, application of PCM is limited by the issues of low thermal conductivity, leakage and strong rigidity. In this work, a novel form-stable and thermally induced flexible composite PCM inspired by shape memory polymers was successfully prepared. Here, paraffin (PA) with large latent heat was employed as PCM, olefin block copolymer (OBC) performed as the supporting material and expanded graphite (EG) was the additives for thermal conductivity enhancement. The structure and properties of prepared composites were characterized by FT-IR, XRD, SEM, DSC and TG. There was a good physicochemical compatibility among the components of the PA/OBC/EG composites. Two well-distinguished melting points could be observed and the obtained composites presented a good thermal stability during the working temperature range. Further, the composites also demonstrated excellent form-stable property according to the leakage test. There was no obvious PA leakage when the mass fraction of OBC in PA/OBC blends was 20% and EG had a positive effect on the leakage rate. Simultaneously, the good softness and flexibility achieved by triggering the phase transition of PA could lead to many deformation modes such as bend and compression, which were beneficial for thermal contact resistance decrease and installation improvement. Finally, the heat transfer characteristics were investigated experimentally. The heating and cooling processes were mainly affected by three factors, namely, thermal conduction, natural convection and absorption of latent heat. With EG impregnated in the composites, the heating and cooling rate could be amplified and thus improved the overall thermal performance. The results presented in this work indicate that the prepared composite PCM possesses a potential application for thermal energy storage and thermal management.

Electric vehicles with green power system are viable alternatives to reduce greenhouse gas emissions and dependence on fossil energy resources. The power source such as Li-ion battery has high sensitivity to temperature, which is a challenge related to battery thermal management. Battery thermal management system plays a vital role in the high efficiency, dependability and security of these batteries. Modern commercial electric vehicles normally use liquid based battery thermal management system, which has high heat transfer efficiency with the function of cooling or heating. This paper firstly looks at the effects of temperature on the battery performance from three aspects: low temperature, high temperature and differential temperature. Then the battery management system is discussed with the main emphasis on battery modeling methods and thermal management strategies. Further, a systematic review of liquid based system is presented in terms of direct and indirect contact mode. Progress made in liquid channel configuration and heat transfer fluid aiming at improving the overall thermal performance is also discussed. With the function of liquid-gas phase change process, the heat pipe based battery thermal management is feasible and effective for its high heat transfer efficiency. To further facilitate vehicle-mounted energy optimization, an integrated vehicle thermal management system with appropriate energy allocation is required. In addition, the battery thermal management system connected with the other subsystems (e.g., heating ventilation air conditioning system) by utilizing the liquid circulation in vehicle thermal management has great potential in energy-saving and efficiency promotion.

Air-cooled battery thermal management system (BTMS) is one of the most commonly used solutions to maintain the appropriate temperature of battery pack in electric vehicle. In the present study, the cooling efficiency of the air-cooled BTMS is improved through designing the flow pattern of the system. The BTMSs with various positions of the inlet region and the outlet region are considered. The performances of the systems are evaluated using the numerical method, the effectiveness of which is validated by experiment. The results show that the symmetrical BTMS with the inlet and outlet located on the middle of the plenums achieves high cooling efficiency. Subsequently, an optimization strategy is proposed to optimize the positions of the inlet region and the outlet region for cooling efficiency improvement of the system. It is found that the optimized BTMS has better cooling performance than other BTMSs. Compared to the typical BTMS with Z-type flow, the maximum temperature and the maximum cell temperature difference of the optimized BTMS are reduced by 4.5 K and 7.7 K, respectively. Compared to the symmetrical system, the maximum cell temperature difference of the optimized BTMS is reduced by 1.7 K with the power consumption decreased by 12%.

The optimal treatment for acute non-A-non-B aortic dissection remains controversial. Triple-branched stent graft (TBSG) implantation has been used to treat acute type A aortic dissection. This study aimed to evaluate the safety and efficacy of TBSG as a treatment for acute non-A-non-B aortic dissection.Fifty patients with non-A-non-B dissection received TBSG implantation in our center between January 2014 and December 2019. Early mortality, morbidity, and dissected aorta remodeling during follow-up were calculated.There were no deaths in-hospital or within 30 days. Postoperative complications included pneumonia (n = 12), acute kidney injury (n = 6; preoperative renal malperfusion, n = 4), transient cerebral injury (n = 6; preoperative cerebral malperfusion, n = 4), pleural effusion (n = 4), and pericardial effusion (n = 2). During follow-up, 1 patient experienced a stroke, and 2 patients required secondary interventional therapy for residual dissection below the level of the TBSG. All implanted TBSGs had good positioning, and all sidearm stent graft grafts were fully patent. No retrograde aortic dissection or type I endoleak was detected.TBSG implantation for acute non-A-non-B aortic dissection had a low incidence of mortality and morbidity, featuring good remodeling of the dissected aortic wall during follow-up. The early outcomes of this technique were satisfactory.

Vegetation indices (VIs) data derived from satellite imageries play a vital role in land surface vegetation and dynamic monitoring. Due to the excessive noises (e.g., cloud cover, atmospheric contamination) in daily VI data, temporal compositing methods are commonly used to produce composite data to minimize the negative influence of noise over a given compositing time interval. However, VI time series with high temporal resolution were preferred by many applications such as vegetation phenology and land change detections. This study presents a novel strategy named DAVIR-MUTCOP (DAily Vegetation Index Reconstruction based on MUlti-Temporal COmposite Products) method for normalized difference vegetation index (NDVI) time-series reconstruction with high temporal resolution. The core of the DAVIR-MUTCOP method is a combination of the advantages of both original daily and temporally composite products, and selecting more daily observations with high quality through the temporal variation of temporally corrected composite data. The DAVIR-MUTCOP method was applied to reconstruct high-quality NDVI time-series using MODIS multi-temporal products in two study areas in the continental United States (CONUS), i.e., three field experimental sites near Mead, Nebraska from 2001 to 2012 and forty-six AmeriFlux sites evenly distributed across CONUS from 2006 to 2010. In these two study areas, the DAVIR-MUTCOP method was also compared to several commonly used methods, i.e., the Harmonic Analysis of Time-Series (HANTS) method using original daily observations, Savitzky–Golay (SG) filtering using daily observations with cloud mask products as auxiliary data, and SG filtering using temporally corrected composite data. The results showed that the DAVIR-MUTCOP method significantly improved the temporal resolution of the reconstructed NDVI time series. It performed the best in reconstructing NDVI time-series across time and space (coefficient of determination (R2 = 0.93~0.94) between reconstructed NDVI and ground-observed LAI). DAVIR-MUTCOP method presented the highest robustness and accuracy with the change of the filtering parameter (R2 = 0.99~1.00, bias = 0.001, root mean square error (RMSE) = 0.020). Only MODIS data were used in this study; nevertheless, the DAVIR-MUTCOP method proposed a universal and potential way to reconstruct daily time series of other VIs or from other operational sensors, e.g., AVHRR and VIIRS.

The quantum anomalous Hall (QAH) effect in magnetic topological insulator (TI) represents a new state of matter originated from the interplay between topology and magnetism. The defining characteristics of the QAH ground state are the quantized Hall resistivity ($\rho_{yx}$) and vanishing longitudinal resistivity ($\rho_{xx}$) in the absence of external magnetic field. A fundamental question concerning the QAH effect is whether it is merely a zero-magnetic-field quantum Hall (QH) effect, or if it can host unique quantum phases and phase transitions that are unavailable elsewhere. The most dramatic departure of the QAH systems from other QH systems lies in the strong magnetic disorders that induce spatially random magnetization. Because disorder and magnetism play pivotal roles in the phase diagram of two-dimensional electron systems, the high degree of magnetic disorders in QAH systems may create novel phases and quantum critical phenomena. In this work, we perform systematic transport studies of a series of magnetic TIs with varied strength of magnetic disorders. We find that the ground state of QAH effect can be categorized into two distinct classes: the QAH insulator and anomalous Hall (AH) insulator phases, as the zero-magnetic-field counterparts of the QH liquid and Hall insulator in the QH systems. In the low disorder limit of the QAH insulator regime, we observe a universal quantized longitudinal resistance $\rho_{xx} = h/e^{2}$ at the coercive field. In the AH insulator regime, we find that a magnetic field can drive it to the QAH insulator phase through a quantum critical point with distinct scaling behaviors from that in the QH phase transition. We propose that the transmission between chiral edge states at domain boundaries, tunable by disorder and magnetic fields, is the key for determining the QAH ground state., Comment: 17 pages, 5 figures

In this paper, a three-dimensional thermal model of a prismatic battery with multi-layer structure was established and validated by the measured surface temperature of the battery. The proposed model was used to analyze and optimize thermal performance of the battery in three cases that its surface was integrated with one of three shape-stabilized phase change material (PCM) configurations. The results showed that the internal anisotropic characteristics of the prismatic battery have significant effect on the heat transfer and thermal performance of the configurations. The configuration that PCM wrapped around the battery had the best performing temperature rising and distribution due to the large thermal storage capacity of PCM and highest contact area between the PCM and the battery. Furthermore, there were critical values of PCM thickness and convective heat transfer coefficient (e.g., 2.08 mm and 10 W m−2 K−1 for PCM around the cell) at which the process of phase change was almost completed, and the temperature distribution was significantly different across these values. The temperature gradient across the cell decreased as the thickness increased. However, the effect of increasing convective heat transfer coefficient on the decrease of temperature gradient was limited due to the relatively low internal heat conduction ability of the battery.

High fertilizer application and over-irrigation in sugarcane systems can cause considerable N2O emissions. Optimized water-fertilization management which reduces N2O emissions, while maintaining sugarcane biomass, is crucial, but may affect nitrogen fixation by sugarcane. This study evaluated the combined effect of water-fertilization on sugarcane biomass and nitrogen fixation in field trials in southern China. Treatments included drip and spray irrigation, with three levels (0% (low), 50% (medium), 100% (high)) of irrigation and of fertilizer. A rain-fed crop (no irrigation or fertilizer) was included as the control. The results showed that (1) spray irrigation with medium water and high fertilization increased biomass. The optimum combination in sugarcane elongation stage was drip irrigation with medium water and high fertilization, while drip irrigation with high water and high fertilization was the best choice for maturity stage. (2) For sugarcane nitrogen (δ15N) content, spray irrigation with medium water and high fertilization was the best combination in seedling and tillering stages. The optimum combination in the elongation stage was drip irrigation with medium water and high fertilization, and in maturity stage was drip irrigation with high water and high fertilization. (3) For soil (δ15N content), drip irrigation with high water and high fertilization proved optimal for seedling, tillering, and maturity stages. (4) In seedling stage, sugarcane (δ15N content) was found to be strongly correlated with leaf area index, soil water, soil temperature, and soil electrical conductivity. Soil (δ15N content) was correlated with photosynthesis and soil temperature. In conclusion, drip irrigation appears most suitable for field planting, while the best treatment in seedling and tillering stages is medium water-high fertilization, and that the best in elongation stage is high water-medium fertilization. The optimum water-fertilizer combinations identified here can provide a scientific basis for optimization and management of irrigation and fertilization in China and other regions with similar environments.

The hybrid thermal management scheme for lithium-ion battery combining the advantages of various thermal management strategies has been widely adopted. However, due to the complex influence parameters involved in the hybrid thermal management system, its optimal design has become a difficult problem. In this study, a hybrid thermal management system based on phase change material (PCM), liquid cooling, and heat pipe is first designed, and then a precise and reliable numerical heat transfer model is established. In order to optimize the system and improve the optimization efficiency, the Adaptive-Kriging-High dimensional model representation (HDMR) method is used to construct a surrogate model of the thermal management system, and the influencing factors sensitivity analysis and optimization design of the hybrid thermal management system are also conducted. The results show that the thermal conductivity of PCM, the thickness of PCM, the length of heat pipe and the velocity of inlet water have a significant influence on the maximum temperature and temperature difference of the battery system. According to the optimization design of these four factors based on the multi-objective particle swarm optimization (MOPSO), it is found that the optimized thermal management system has the best ability to dissipate heat and maintain temperature uniformity as compared to the original design. In addition, this optimization system has the ability to prevent thermal runaway propagation under the condition of thermal abuse conditions. With these prominent performances, the proposed method is expected to provide insights into the engineering design and optimization of the battery thermal management system for electric vehicle.

A coupled battery thermal management (BTM) system based on novel quaternary phase change material plate (PCMP) is developed to balance the temperature in rectangular LiFePO 4 battery modules. Paraffin (PA), expanded graphite (EG), low-density polyethylene, and copper mesh were combined into a quaternary PCMP to strengthen the heat transfer. The thermal conductivity of the PCMP with double copper mesh (DCM-PCMP) was increased by 36.0% compared with that of PCMP composed of EG and PA. Accordingly, the DCM-PCMP reduced the maximum temperature and maximum temperature difference within the battery module to less than 52.8 and 3 °C, respectively, both the lowest among the four methods. The coupled system based on DCM-PCMP and forced air convection showed excellent thermal performance, which contributed to a stable temperature during the cycling process. Thermal simulations showed that the double outstretched copper mesh through the DCM-PCMP disturbed the air flow tempestuously, giving rise to a decrease in thermal resistance. Thus, the temperature distribution inside the battery and temperature uniformity within the battery module were both better optimized. The analysis of the power consumption of the DCM-PCMP method revealed that the optimal heat dissipation performance for the battery module is achieved at an air velocity of 6 m/s.

Thermal management is a crucial strategy that needs to be carefully considered for lithium-ion batteries under extreme operating conditions. One promising approach is the use of phase change material (PCM), which can bring benefits such as passively thermal buffering and extending lifespan. In this paper, a paraffin/expanded graphite (EG) composites based battery module (PCM module), as well as the two dimensional thermal model is proposed. The effects of different EG mass fractions associated with different phase change enthalpy and thermal conductivity are investigated firstly under high-rate discharge condition. The results show that an optimal mass fraction of EG is needed to achieve the best thermal performance and the EG mass fraction of 15–20% is recommended to be used for battery thermal management. In order to further improve the overall performance, we also design a novel pyrolytic graphite sheets (PGS)-enhanced paraffin/EG composites based battery module (PCM/PGS module). EG with porous structure can create the primary thermal conductive network for PCM to increase the heat absorption rate. PGS forms the secondary thermal conductive network for the module to improve the whole thermal homogeneity. As a result, the as-designed PCM/PGS module presents much better heat dissipation performance and temperature uniformity compared with the PCM module during discharge–charge cycles. Also, the introduction of PGS is beneficial for thermal fluctuations and energy saving, for instance, the thermal performance of PCM/PGS module with a convective heat transfer coefficient of 50 W m−2 K−1 is comparable to PCM module with 200 W m−2 K−1. In the case of failure mode, to achieve the prevention of thermal runaway propagation, the spacing between cells for PCM module is up to 14 mm. However, the use of PGS lowers the spacing (i.e. less composite PCM consumption) by a decreasing rate of ∼71.4% in comparison with PCM module.

In this paper, a heat pipe-assisted phase change material (PCM) based battery thermal management (BTM) system is designed to fulfill the comprehensive energy utilization for electric vehicles and hybrid electric vehicles. Combining the large heat storage capacity of the PCM with the excellent cooling effect of heat pipe, the as-constructed heat pipe-assisted PCM based BTM is feasible and effective with a relatively longer operation time and more suitable temperature. The experimental results show that the temperature maldistribution of battery module can be influenced by heat pipes when they are activated under high discharge rates of the batteries. Moreover, with forced air convection, the highest temperature could be controlled below 50 °C even under the highest discharge rate of 5C and a more stable and lower temperature fluctuation is obtained under cycling conditions. Meanwhile, the effectiveness of further increasing air velocity (i.e., more fan power consumption) is limited when the highest temperature continues to reduce at a lower rate due to the phase transition process of PCM. These results are expected to provide insights into the design and optimization of BTM systems.

The quantum anomalous Hall effect in magnetic topological insulators provides an ideal platform for building topological phases and devices. Here we construct a bilayer structure consisting of two magnetic topological insulator films with drastically different coercive field. In the intermediate field regime, the two quantum anomalous insulators have opposite spin orientation and counter-propagating edge states, thus realizing a synthetic quantum spin Hall phase. Multi-terminal transport measurements show that a moderate magnetic field can tune the system between chiral and helical edge state transport regimes. The interlayer transport realizes quantized spin-biased resistance, and the coupling between the two edges can be tuned by an epitaxially grown spacer layer in a sandwich structure. The tunable chiral and helical edge states in the quantum anomalous Hall bilayer may find unique applications in spintronics and topological quantum computation.

Background Liver cancer (LC) is the sixth most common cancer and the second leading cause of cancer mortality worldwide, and its incidence rate is high in China. Methods In this study, we aimed to investigate the contribution of MIR137HG (MIR137 Host Gene) polymorphisms to LC risk in a case–control study with 432 LC patients and 430 healthy controls. A logistic recession model was used to evaluate the effects of candidate single nucleotide polymorphisms (SNPs) on LC risk. HaploReg v 4.1 database was conducted to predict the potential functionality of SNPs. Results The results revealed that rs17371457 and rs7554283 in the MIR137HG gene were correlated with an enhanced LC risk under the allele (P = 0.001 and P = 0.043, respectively) and genetic models (P < 0.05). When the sample was stratified by gender and age, statistically significant associations were found. Rs9440302, rs17371457 and rs7554283 were associated with an increased the risk of LC among individuals aged >55 years (P < 0.05); rs17371457 was related to higher LC risk in males (P < 0.05). Similarly, the haplotype AG constituted by rs12333983 and rs3735451 significantly increased LC risk in Chinese Li population (P = 0.043). Six SNPs distributed in MIR137HG were successfully predicted as regulatory SNPs with different biological functions. Conclusion Our research firstly showed that MIR137HG gene polymorphisms were implicated in LC susceptibility among Chinese Li population.

In this paper, the low temperature performance of lithium-ion batteries under various charge rates ranged from 0.2 C to 1 C were studied. To shed some light on the degradation modes and aging mechanism, non-invasive and post-mortem analysis were adopted. The results reveal that there is a considerable reversible capacity loss and internal resistance increase with the increase in charge rate. Particularly, the relative capacity of 1C charged cell after 150 cycles is below 0.8, indicating the end of life is achieved. In addition, the increased internal resistance will lead to a substantial increase in heat generation rate, which is an important factor to the thermal safety control of battery related to the design of thermal management strategy. Besides the resistance increase, two major degradation modes i.e., loss of lithium inventory and loss of active material are demonstrated according to the differential voltage and incremental capacity analysis. It is found that lithium plating is regarded as the main aging mechanism. The anode material of cycled cell display distinct deterioration even exfoliated from the copper foil upon a macroscopic check, and a thick deposited layer morphology and cracking of the layer is visible from a micro point of view through cell opening. During the low temperature charging, lithium plating could be triggered due to the limitation of charge transfer resulted from high-rate charge as well as the limitation of solid-state diffusion resulted from low temperature. The continuous lithium-consuming during cycling will lead to secondary SEI formation, which may result in dead lithium and stripping, eventually reversible capacity loss.

We report transport measurements on Josephson junctions consisting of Bi2Te3 topological insulator (TI) thin films contacted by superconducting Nb electrodes. For a device with junction length L = 134 nm, the critical supercurrent Ic can be modulated by an electrical gate which tunes the carrier type and density of the TI film. Ic can reach a minimum when the TI is near the charge neutrality regime with the Fermi energy lying close to the Dirac point of the surface state. In the p-type regime the Josephson current can be well described by a short ballistic junction model. In the n-type regime the junction is ballistic at 0.7 K < T < 3.8 K while for T < 0.7 K the diffusive bulk modes emerge and contribute a larger Ic than the ballistic model. We attribute the lack of diffusive bulk modes in the p-type regime to the formation of p-n junctions. Our work provides new clues for search of Majorana zero mode in TI-based superconducting devices., 6 pages, 4 figures, The manuscript with the same title will be published by Chinese Physics Letters

As an important method for battery thermal management, traditional phase change material (PCM) technology is facing challenges due to the relatively low thermal conductivity, weak skeleton strength and/or leakage phenomenon of PCM. Herein we develop a copper mesh (CM)-enhanced paraffin (PA)/expanded graphite (EG) composite as a composite PCM for battery thermal management. EG with porous structure can absorb liquid phase PA, preventing PA leakage. CM acts as a skeleton to further enhance both the thermal conductivity and strength of the whole module. As a result, the as-constructed CM enhanced PCM of PA/EG plate (PCMP) presents much better heat dissipation performance and temperature uniformity compared to PCMP without CM, especially in harsh working conditions. Moreover, with forced air convection, copper fins exposed from the composite may play a crucial role in not only heat dissipation, but also disturbing the air flow, and thus further strengthen the heat transfer capability.