The Gasbag Phase-change Carbon Dioxide Energy Storage System leverages elastic gasbags to store carbon dioxide under varying geographical conditions.This approach utilizes the phase-change sensible heat effect to effi...The Gasbag Phase-change Carbon Dioxide Energy Storage System leverages elastic gasbags to store carbon dioxide under varying geographical conditions.This approach utilizes the phase-change sensible heat effect to efficiently manage energy storage and release.This technology requires lower pressure and temperature control,resulting in reduced energy consumption and improved efficiency.Additionally,it is less restricted by geographical factors to a certain extent,enabling the formation of a closed-loop system.This contributes to the development of new energy utilization systems.The article examines and compares two experimental energy storage projects employing elastic gasbags to maintain a constant pressure supply of carbon dioxide on the low-pressure side.It further details the precise calculation methods for system cycle efficiency and energy storage density while analyzing energy losses incurred during the storage and release phases.Finally,an economic analysis is conducted using specific data,demonstrating that optimizing temperature and pressure parameters at various nodes enhances overall system efficiency while reducing energy consumption.Furthermore,the study highlights the system's high sensitivity to grid electricity prices.This research is anticipated to contribute to the development of more efficient and reliable energy storage solutions for power systems,addressing the growing energy demands and sustainability challenges.展开更多
Battery storage systems are subject to frequent charging/discharging cycles,which reduce the operational life of the battery and reduce system reliability in the long run.As such,several Battery Management Systems(BMS...Battery storage systems are subject to frequent charging/discharging cycles,which reduce the operational life of the battery and reduce system reliability in the long run.As such,several Battery Management Systems(BMS)have been developed to maintain system reliability and extend the battery’s operative life.Accurate estimation of the battery’s State of Charge(SOC)is a key challenge in the BMS due to its non-linear characteristics.This paper presents a comprehensive review on the most recent classifications and mathematical models for SOC estimation.Future trends for SOC estimation methods are also presented.展开更多
With the increasing demand of high-power and pulsed power electronic devices,environmental-friendly potassium sodium niobate((Na_(0.5)K_(0.5))NbO_(3),KNN)ceramic-based capacitors have attracted much attention in recen...With the increasing demand of high-power and pulsed power electronic devices,environmental-friendly potassium sodium niobate((Na_(0.5)K_(0.5))NbO_(3),KNN)ceramic-based capacitors have attracted much attention in recent years owning to the boosted energy storage density(W_(rec)).Nevertheless,the dielectric loss also increases as the external electric field increases,which will generate much dissipated energy and raise the temperature of ceramic capacitors.Thus,an effective strategy is proposed to enhance the energy storage efficiency(η)via tailoring relaxor behavior and bad gap energy in the ferroelectric 0.9(Na_(0.5)K_(0.5))-NbO_(3)-0.1Bi(Zn_(2/3)(Nb_(x)Ta_(1−x))1/3)O_(3) ceramics.On the one hand,the more diverse ions in the B-sites owing to introducing the Ta could further disturb the long-range ferroelectric polar order to form the short−range polar nanoregions(PNRs),resulting in the highη.On the other hand,the introduction of Ta ions could boost the intrinsic band energy gap and thus improve the Eb.As a result,high Wrec of 3.29 J/cm^(3) and ultrahighηof 90.1%at the high external electric field of 310 kV/cm are achieved in x=0.5 sample.These results reveal that the KNN-based ceramics are promising lead-free candidate for high-power electronic devices.展开更多
Designing dielectric materials with the tremendous energy storage density is fundamentally important for developing pulse power capacitors.An effective approach was proposed to favorably modify the dielectric energy s...Designing dielectric materials with the tremendous energy storage density is fundamentally important for developing pulse power capacitors.An effective approach was proposed to favorably modify the dielectric energy storage properties(ESP)of Bi_(0.5)Na_(0.5)TiO_(3) ceramics using CaTiO_(3) incorporation.The dielectric breakdown strength was effectively enhanced,and simultaneously the relaxor behavior was optimized to lower the remnant polarization,which is resulted from the decreased grains size with the introduction of Ca^(2+)ion.Remarkably,at a CaTiO_(3) doping level of 0.2,a 0.8Bi_(0.5)Na_(0.5)TiO_(3)-0.2CaTiO_(3)(0.8BNT-0.2CT)ceramic obtained both high energy storage density(Wtotal)of~1.38 J/cm^(3) together with excellent efficiency(h)of~91.3%.Furthermore,an ultrafast discharge response speed(t0:9)~94 ns was achieved in 0.8BNT-0.2CT ceramic,as well as tremendous current density(C_(D)~1520 A/cm2)and power density(P_(D)~115 MW/cm^(3)).This study not only revealed the superior ESP mechanism as regards Bi_(0.5)Na_(0.5)TiO_(3) based ceramics but also provided candidate materials in pulse power capacitor devices.展开更多
●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were ...●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were related to soil microbial diversity.●Root litter quality had little effect on soil physicochemical properties.●High root litter quality was the main driver of enhanced soil C storage efficiency.Decomposing root litter is a major contributor to soil carbon(C)storage in forest soils.During decomposition,the quality of root litter could play a critical role in soil C storage.However,it is unclear whether root litter quality influences soil C storage efficiency.We conducted a two-year greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality,represented by C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency in subtropical forest soils in China.‘High-quality’root litter(C/N ratio=26)decayed faster during the first year(0−410 days),whereas‘low-quality’root litter(C/N ratio=46)decomposed faster toward the end of the two-year period(598−767 days).However,over the two years of the study,mass loss from high-quality root litter(29.14±1.42%)was lower than‘low-quality’root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency(i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly greater for high-quality root litter,with twice as much litter-derived C stored in soils compared to low-quality root litter at the end of the experiment.Root litter quality likely influenced soil C storage via changes in microbial diversity,as the decomposition of high-quality litter declined with increasing bacterial diversity,whereas the amount of litter-derived soil C from low-quality litter increased with fungal diversity.Our results thus reveal that root litter quality mediates decomposition and C storage in subtropical forest soils in China and future work should consider the links between root litter quality and soil microbial diversity.展开更多
Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage tech...Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage technologies,the coupled approach of power-to-hydrogen(H2)and underground H2storage(UHS)offers advantages such as extended storage duration and large-scale capacity,making it highly promising for future development.However,during UHS,particularly in porous media,microbial metabolic processes such as methanogenesis,acetogenesis,and sulfate reduction may lead to H2consumption and the production of byproducts.These microbial activities can impact the efficiency and safety of UHS both positively and negatively.Therefore,this paper provides a comprehensive review of experimental,numerical,and field studies on microbial interactions in UHS within porous media,aiming to capture research progress and elucidate microbial effects.It begins by outlining the primary types of UHS and the key microbial metabolic processes involved.Subsequently,the paper introduces the experimental approaches for investigating gas-water-rock-microbe interactions and interfacial properties,the models and simulators used in numerical studies,and the procedures implemented in field trials.Furthermore,it analyzes and discusses microbial interactions and their positive and negative impacts on UHS in porous media,focusing on aspects such as H2consumption,H2flow,and storage safety.Based on these insights,recommendations for site selection,engineering operations,and on-site monitoring of UHS,as well as potential future research directions,are provided.展开更多
To obtain the precise calculation method for the peak energy density and energy evolution properties of rocks subjected to uniaxial compression(UC)before the post-peak stage,particularly at s0.9sc(s denotes stress and...To obtain the precise calculation method for the peak energy density and energy evolution properties of rocks subjected to uniaxial compression(UC)before the post-peak stage,particularly at s0.9sc(s denotes stress and sc is the peak strength),extensive UC and uniaxial graded cyclical loading-unloading(GCLU)tests were performed on four rock types.In the GCLU tests,four unloading stress levels were designated when σ<0.9σc and six unloading stress levels were designated forσ≥0.9σc.The variations in the elastic energy density(ue),dissipative energy density(ud),and energy storage efficiency(C)for the four rock types under GCLU tests were analyzed.Based on the variation of ue whenσ≥0:9σc,a method for calculating the peak energy density was proposed.The energy evolution in rock under UC condition before the post-peak stage was examined.The relationship between C0.9(C atσ≥0:9σc)and mechanical behavior of rocks was explored,and the damage evolution of rock was analyzed in view of energy.Compared with that of the three existing methods,the accuracy of the calculation method of peak energy density proposed in this study is higher.These findings could provide a theoretical foundation for more accurately revealing the failure behavior of rock from an energy perspective.展开更多
The fast and reversible sodiation/desodiation of anode materials remains an indelible yet fascinating target.Herein, a class of the densely packed Si/MXene composite microspheres is constructed and prepared, taking ad...The fast and reversible sodiation/desodiation of anode materials remains an indelible yet fascinating target.Herein, a class of the densely packed Si/MXene composite microspheres is constructed and prepared, taking advantages of the synergistic effects of the activated Si nanoparticles and conductive flower-like MXene microspheres with ample ion-diffusion pathways. Consequently,the intrinsic MXene nanosheets with intelligently regulated interlayer spacing can accommodate the volume change induced strain during cycling, and the strong interaction between the Si and MXene matrix greatly contributes to the robust structural stability. As expected, the Si/MXene composite architecture exhibits boosted sodium storage performance, in terms of an inspiring reversible capacity of 751 mAh·g^(-1)at 0.1 A·g^(-1), remarkable long-term cycling stability of 376 mAh·g^(-1)at 0.1 A·g^(-1) over 500 cycles, and outstanding rate capability(after one consecutive current density changing from 0.1 to 2.0 A·g^(-1), a large capacity of 275 mAh·g^(-1) is regained after suddenly returning the initial current density back to 0.1 A·g^(-1) and in the subsequent 200 cycles this composite architecture anode still delivers a capacity of 332 mAh·g^(-1)). The kinetics analysis indicates superior pseudocapacitive property, high electronic conductivity, and favorable sodium-ion adsorption and diffusion capability,confirming fast sodium storage performance. Impressively, ex-situ X-ray diffraction and selected area electron diffraction characterizations corroborate the formation of NaSi;as the main sodiation products during the reversible evolutions of cycled proceeding with sodium-ion insertion. This work sheds light on the elaborate design of silicon-based nanostructured anodes towards advanced high-performance sodium-ion batteries.展开更多
A storage-efficient reconstruction framework for cartographic planar contours is developed.With a smaller number of control points,we aim to calculate the area and perimeter as well as to reconstruct a smooth curve.Th...A storage-efficient reconstruction framework for cartographic planar contours is developed.With a smaller number of control points,we aim to calculate the area and perimeter as well as to reconstruct a smooth curve.The input data forms an oriented contour,each control point of which consists of three values:the Cartesian coordinates(x,y)and tangent angleθ.Two types of interpolation methods are developed,one of which is based on an arc spline while the other one is on a cubic Hermite spline.The arc spline-based method reconstructs a G1 continuous curve,with which the exact area and perimeter can be calculated.The benefit of using the Hermite spline-based method is that it can achieve G2 continuity on most control points and can obtain the exact area,whereas the resulting perimeter is approximate.In a numerical experiment for analytically defined curves,more accurate computation of the area and perimeter was achieved with a smaller number of control points.In another experiment using a digital elevation model data,the reconstructed contours were smoother than those by a conventional method.展开更多
Finite element（FE） is a powerful tool and has been applied by investigators to real-time hybrid simulations（RTHSs）. This study focuses on the computational efficiency, including the computational time and accuracy...Finite element（FE） is a powerful tool and has been applied by investigators to real-time hybrid simulations（RTHSs）. This study focuses on the computational efficiency, including the computational time and accuracy, of numerical integrations in solving FE numerical substructure in RTHSs. First, sparse matrix storage schemes are adopted to decrease the computational time of FE numerical substructure. In this way, the task execution time（TET） decreases such that the scale of the numerical substructure model increases. Subsequently, several commonly used explicit numerical integration algorithms, including the central difference method（CDM）, the Newmark explicit method, the Chang method and the Gui-λ method, are comprehensively compared to evaluate their computational time in solving FE numerical substructure. CDM is better than the other explicit integration algorithms when the damping matrix is diagonal, while the Gui-λ（λ = 4） method is advantageous when the damping matrix is non-diagonal. Finally, the effect of time delay on the computational accuracy of RTHSs is investigated by simulating structure-foundation systems. Simulation results show that the influences of time delay on the displacement response become obvious with the mass ratio increasing, and delay compensation methods may reduce the relative error of the displacement peak value to less than 5% even under the large time-step and large time delay.展开更多
A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity...A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these non-uniform access behaviors,an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy,facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies,the approach excels at identifying and evicting infrequently used data,thereby optimizing cache utilization.The evaluation shows impressive performance improvement,especially on workloads with irregular access patterns.Benefiting from fine granularity,the proposal achieves superior storage efficiency compared with commonly used cache management schemes,providing a potential optimization opportunity for modern resource-constrained processors,such as spacecraft processors.Furthermore,the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications,enhancing their overall efficacy.展开更多
Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum n...Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum networks.展开更多
In this study,the influence of the phase-change cooling storage system on integrating and controlling of the combined cooling,heating,and power system was analyzed through experiments and computational fluid dynamics ...In this study,the influence of the phase-change cooling storage system on integrating and controlling of the combined cooling,heating,and power system was analyzed through experiments and computational fluid dynamics simulations.The model of three-dimensional phase change material plate and cold storage tank was established and verified.The phase change material selected in this study is a eutectic salt with a phase change temperature of 8℃.The thermodynamic performance of the cold storage tank filled with phase change material plates was calculated,and the energy storage and release efficiency of the phase-change cooling storage system was analyzed.The results indicate that the phase change process correlates positively with the heat transfer fluid flow rate.The heat transfer fluid flow rates of 1.2 m^(3)/h,1.6 m^(3)/h,and 2.0 m^(3)/h all allow the phase change material within the encapsulation module to completely solidify within 8 hours;the flow rate required for melting is not less than 2.0 m^(3)/h,and the highest energy storage efficiency is up to 72%.Considering the thermodynamic performance of the phase-change cooling storage system,it is recommended to use a heat transfer fluid flow rate of 1.6 m^(3)/h for the cooling charge process and 2.0 m^(3)/h for the cooling release process.展开更多
Cement-based materials are the foundation of modern buildings but suffer from intensive energy consumption.Utilizing cement-based materials for efficient energy storage is one of the most promising strategies for real...Cement-based materials are the foundation of modern buildings but suffer from intensive energy consumption.Utilizing cement-based materials for efficient energy storage is one of the most promising strategies for realizing zero-energy buildings.However,cement-based materials encounter challenges in achieving excellent electrochemical performance without compromising mechanical properties.Here,we introduce a biomimetic cement-based solid-state electrolyte(labeled as l-CPSSE)with artificially organized layered microstructures by proposing an in situ ice-templating strategy upon the cement hydration,in which the layered micropores are further filled with fast-ion-conducting hydrogels and serve as ion diffusion highways.With these merits,the obtained l-CPSSE not only presents marked specific bending and compressive strength(2.2 and 1.2 times that of traditional cement,respectively)but also exhibits excellent ionic conductivity(27.8 mS·cm^(-1)),overwhelming most previously reported cement-based and hydrogel-based electrolytes.As a proof-of-concept demonstration,we assemble the l-CPSSE electrolytes with cement-based electrodes to achieve all-cement-based solid-state energy storage devices,delivering an outstanding full-cell specific capacity of 72.2 mF·cm^(-2).More importantly,a 5×5 cm^(2) sized building model is successfully fabricated and operated by connecting 4 l-CPSSE-based full cells in series,showcasing its great potential in self-energy-storage buildings.This work provides a general methodology for preparing revolutionary cement-based electrolytes and may pave the way for achieving zero-carbon buildings.展开更多
To meet the demands of the global energy transition,photothermal phase change energy storage materials have emerged as an innovative solution.These materials,utilizing various photothermal conversion carriers,can pass...To meet the demands of the global energy transition,photothermal phase change energy storage materials have emerged as an innovative solution.These materials,utilizing various photothermal conversion carriers,can passively store energy and respond to changes in light exposure,thereby enhancing the efficiency of energy systems.Photothermal phase change energy storage materials show immense potential in the fields of solar energy and thermal management,particularly in addressing the intermittency issues of solar power.Their multifunctionality and efficiency offer broad application prospects in new energy technologies,construction,aviation,personal thermal management,and electronics.展开更多
Shortages and fluctuations in precipitation are influential limiting factors for the sustainable cultivation of rain-fed winter wheat on the Loess Plateau of China. Plastic film mulching is one of the most effective w...Shortages and fluctuations in precipitation are influential limiting factors for the sustainable cultivation of rain-fed winter wheat on the Loess Plateau of China. Plastic film mulching is one of the most effective water management practices to improve soil moisture, and may be useful in the Loess Plateau for increasing soil water storage. A field experiment was conducted from July 2010 to June 2012 on the Loess Plateau to investigate the effects of mulching time and rates on soil water storage, evapotranspiration （ET）, water use efficiency （WUE）, and grain yield. Six treatments were conducted： （1） early mulching （starting 30 days after harvest） with whole mulching （EW）; （2） early mulching with half mulching （EH）; （3） early mulching with no mulching （EN）; （4） late mulching （starting 60 days after harvest） with whole mulching （LW）; （5） late mulching with half mulching （LH）; and （6） late mulching with no mulching （LN）. EW increased precipitation storage efficiency during the fallow periods of each season by 18.4 and 17.8%, respectively. EW improved soil water storage from 60 days after harvest to the booting stage and also outperformed LN by 13.8 and 20.9% in each growing season. EW also improved spike number per ha by 13.8 and 20.9% and grain yield by 11.7 and 17.4% during both years compared to LN. However, EW decreased WUE compared with LN. The overall results of this study demonstrated that EW could be a productive and efficient practice to improve wheat yield on the Loess Plateau of China.展开更多
At present,water and fertilizer use efficiency is low in many cultivation areas in southern China.Studies show that the buried straw layer can effectively conserve water and fertilizer.To investigate the optimal irrig...At present,water and fertilizer use efficiency is low in many cultivation areas in southern China.Studies show that the buried straw layer can effectively conserve water and fertilizer.To investigate the optimal irrigation upper limit above the straw barrier and its effect on soil moisture and nitrogen distribution,an indoor soil column experiment was conducted.Six treatments were designed consisting of two levels of straw layer i.e.,(with and without buried straw layer at 25 cm depth),and three irrigation water upper limits i.e.,(saturated moisture content(s),field water holding capacity(f),and 80%of field water holding capacity(0.8f)as the upper limit of irrigation).The result revealed that the buried straw layer can inhibit water infiltration and significantly increase the water storage capacity and water storage efficiency of 0-25 cm soil depth.Under the condition of no evaporation,when the upper limit of irrigation water does not exceed the field water holding capacity,the storage efficiency of 0-25 cm soil water reaches 89%-91%after 6 d.Moreover,a buried straw layer can inhibit the deep percolation of nitrate nitrogen and increase the amount of nitrate-nitrogen in 0-25 cm soil.The 80%field water holding capacity irrigation upper limit combined with straw interlayer treatment had a higher nitrate-nitrogen content in the 0-25 cm soil layer than other treatments.Therefore,80%of field water holding capacity as the upper limit of irrigation combined with buried straw layer is the optimal strategy to conserve soil water and nitrogen in the upper soil profile.展开更多
基金funded by the Natural Science Foundation of Heilongjiang Province,China(Grant No.PL2024E027)。
文摘The Gasbag Phase-change Carbon Dioxide Energy Storage System leverages elastic gasbags to store carbon dioxide under varying geographical conditions.This approach utilizes the phase-change sensible heat effect to efficiently manage energy storage and release.This technology requires lower pressure and temperature control,resulting in reduced energy consumption and improved efficiency.Additionally,it is less restricted by geographical factors to a certain extent,enabling the formation of a closed-loop system.This contributes to the development of new energy utilization systems.The article examines and compares two experimental energy storage projects employing elastic gasbags to maintain a constant pressure supply of carbon dioxide on the low-pressure side.It further details the precise calculation methods for system cycle efficiency and energy storage density while analyzing energy losses incurred during the storage and release phases.Finally,an economic analysis is conducted using specific data,demonstrating that optimizing temperature and pressure parameters at various nodes enhances overall system efficiency while reducing energy consumption.Furthermore,the study highlights the system's high sensitivity to grid electricity prices.This research is anticipated to contribute to the development of more efficient and reliable energy storage solutions for power systems,addressing the growing energy demands and sustainability challenges.
基金This work was supported by research and innovation management center(RIMC)UNIMAS through Fundamental Research Grant Scheme FRGS/1/2017/TK10/UNIMAS/03/1,Ministry of Higher Education,Malaysia.
文摘Battery storage systems are subject to frequent charging/discharging cycles,which reduce the operational life of the battery and reduce system reliability in the long run.As such,several Battery Management Systems(BMS)have been developed to maintain system reliability and extend the battery’s operative life.Accurate estimation of the battery’s State of Charge(SOC)is a key challenge in the BMS due to its non-linear characteristics.This paper presents a comprehensive review on the most recent classifications and mathematical models for SOC estimation.Future trends for SOC estimation methods are also presented.
基金supported by the National Natural Science Foundation of China(Grant No.52072150)the Young Elite Scientists Sponsorship Program of the Chinese Academy of Space Technology(CAST)and Open Foundation of Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices(EFMD2021002Z).
文摘With the increasing demand of high-power and pulsed power electronic devices,environmental-friendly potassium sodium niobate((Na_(0.5)K_(0.5))NbO_(3),KNN)ceramic-based capacitors have attracted much attention in recent years owning to the boosted energy storage density(W_(rec)).Nevertheless,the dielectric loss also increases as the external electric field increases,which will generate much dissipated energy and raise the temperature of ceramic capacitors.Thus,an effective strategy is proposed to enhance the energy storage efficiency(η)via tailoring relaxor behavior and bad gap energy in the ferroelectric 0.9(Na_(0.5)K_(0.5))-NbO_(3)-0.1Bi(Zn_(2/3)(Nb_(x)Ta_(1−x))1/3)O_(3) ceramics.On the one hand,the more diverse ions in the B-sites owing to introducing the Ta could further disturb the long-range ferroelectric polar order to form the short−range polar nanoregions(PNRs),resulting in the highη.On the other hand,the introduction of Ta ions could boost the intrinsic band energy gap and thus improve the Eb.As a result,high Wrec of 3.29 J/cm^(3) and ultrahighηof 90.1%at the high external electric field of 310 kV/cm are achieved in x=0.5 sample.These results reveal that the KNN-based ceramics are promising lead-free candidate for high-power electronic devices.
基金This work was supported by the National Natural Science Foundation of China(Grant NO 51872177)The authors would also like to thank the Natural Science Basic Research Plan in the Shaanxi Province of China(Grant No.2022JQ-338,2021ZDLSF06-03,2021JM-201)+1 种基金Science and Technology Project of Xian,China(Grant No.2020KJRC0014)the Fundamental Research Funds for the Central Universities(Program No.GK202002014).
文摘Designing dielectric materials with the tremendous energy storage density is fundamentally important for developing pulse power capacitors.An effective approach was proposed to favorably modify the dielectric energy storage properties(ESP)of Bi_(0.5)Na_(0.5)TiO_(3) ceramics using CaTiO_(3) incorporation.The dielectric breakdown strength was effectively enhanced,and simultaneously the relaxor behavior was optimized to lower the remnant polarization,which is resulted from the decreased grains size with the introduction of Ca^(2+)ion.Remarkably,at a CaTiO_(3) doping level of 0.2,a 0.8Bi_(0.5)Na_(0.5)TiO_(3)-0.2CaTiO_(3)(0.8BNT-0.2CT)ceramic obtained both high energy storage density(Wtotal)of~1.38 J/cm^(3) together with excellent efficiency(h)of~91.3%.Furthermore,an ultrafast discharge response speed(t0:9)~94 ns was achieved in 0.8BNT-0.2CT ceramic,as well as tremendous current density(C_(D)~1520 A/cm2)and power density(P_(D)~115 MW/cm^(3)).This study not only revealed the superior ESP mechanism as regards Bi_(0.5)Na_(0.5)TiO_(3) based ceramics but also provided candidate materials in pulse power capacitor devices.
基金supported by the National Natural Science Foundation of China(Grant No.31901135)the Guangdong Natural Science Foundation(Grant No.2020A1515011257)+1 种基金the Research Grants Council of the Hong Kong Special Administrative Region,China(Grant Nos.CUHK14302014,CUHK14305515 and CUHK14122521)the Chinese University of Hong Kong(Grant No.4052228).
文摘●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were related to soil microbial diversity.●Root litter quality had little effect on soil physicochemical properties.●High root litter quality was the main driver of enhanced soil C storage efficiency.Decomposing root litter is a major contributor to soil carbon(C)storage in forest soils.During decomposition,the quality of root litter could play a critical role in soil C storage.However,it is unclear whether root litter quality influences soil C storage efficiency.We conducted a two-year greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality,represented by C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency in subtropical forest soils in China.‘High-quality’root litter(C/N ratio=26)decayed faster during the first year(0−410 days),whereas‘low-quality’root litter(C/N ratio=46)decomposed faster toward the end of the two-year period(598−767 days).However,over the two years of the study,mass loss from high-quality root litter(29.14±1.42%)was lower than‘low-quality’root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency(i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly greater for high-quality root litter,with twice as much litter-derived C stored in soils compared to low-quality root litter at the end of the experiment.Root litter quality likely influenced soil C storage via changes in microbial diversity,as the decomposition of high-quality litter declined with increasing bacterial diversity,whereas the amount of litter-derived soil C from low-quality litter increased with fungal diversity.Our results thus reveal that root litter quality mediates decomposition and C storage in subtropical forest soils in China and future work should consider the links between root litter quality and soil microbial diversity.
基金supported by the European Union's“Horizon Europe programme”—LOC3G(Grant No.101129729)the Henan Center for Outstanding Overseas Scientists(Grant No.GZS2024001)。
文摘Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage technologies,the coupled approach of power-to-hydrogen(H2)and underground H2storage(UHS)offers advantages such as extended storage duration and large-scale capacity,making it highly promising for future development.However,during UHS,particularly in porous media,microbial metabolic processes such as methanogenesis,acetogenesis,and sulfate reduction may lead to H2consumption and the production of byproducts.These microbial activities can impact the efficiency and safety of UHS both positively and negatively.Therefore,this paper provides a comprehensive review of experimental,numerical,and field studies on microbial interactions in UHS within porous media,aiming to capture research progress and elucidate microbial effects.It begins by outlining the primary types of UHS and the key microbial metabolic processes involved.Subsequently,the paper introduces the experimental approaches for investigating gas-water-rock-microbe interactions and interfacial properties,the models and simulators used in numerical studies,and the procedures implemented in field trials.Furthermore,it analyzes and discusses microbial interactions and their positive and negative impacts on UHS in porous media,focusing on aspects such as H2consumption,H2flow,and storage safety.Based on these insights,recommendations for site selection,engineering operations,and on-site monitoring of UHS,as well as potential future research directions,are provided.
基金the National Natural Science Foundation of China(Grant Nos.52104133 and 52304227)the Postdoctoral Foundation of Henan Province(Grant No.HN2022015)are appreciated.
文摘To obtain the precise calculation method for the peak energy density and energy evolution properties of rocks subjected to uniaxial compression(UC)before the post-peak stage,particularly at s0.9sc(s denotes stress and sc is the peak strength),extensive UC and uniaxial graded cyclical loading-unloading(GCLU)tests were performed on four rock types.In the GCLU tests,four unloading stress levels were designated when σ<0.9σc and six unloading stress levels were designated forσ≥0.9σc.The variations in the elastic energy density(ue),dissipative energy density(ud),and energy storage efficiency(C)for the four rock types under GCLU tests were analyzed.Based on the variation of ue whenσ≥0:9σc,a method for calculating the peak energy density was proposed.The energy evolution in rock under UC condition before the post-peak stage was examined.The relationship between C0.9(C atσ≥0:9σc)and mechanical behavior of rocks was explored,and the damage evolution of rock was analyzed in view of energy.Compared with that of the three existing methods,the accuracy of the calculation method of peak energy density proposed in this study is higher.These findings could provide a theoretical foundation for more accurately revealing the failure behavior of rock from an energy perspective.
基金the National Natural Science Foundation of China(No.21703209)Shanxi Province Science Foundation(No.201901D211270)+1 种基金Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi,Key Research and Development(R&D)Projects of Shanxi Province(No.201803D121037)the Specialized Research Fund for Sanjin Scholars Program of Shanxi Province and the Graduate Student Education Innovation Projects of Shanxi Province。
文摘The fast and reversible sodiation/desodiation of anode materials remains an indelible yet fascinating target.Herein, a class of the densely packed Si/MXene composite microspheres is constructed and prepared, taking advantages of the synergistic effects of the activated Si nanoparticles and conductive flower-like MXene microspheres with ample ion-diffusion pathways. Consequently,the intrinsic MXene nanosheets with intelligently regulated interlayer spacing can accommodate the volume change induced strain during cycling, and the strong interaction between the Si and MXene matrix greatly contributes to the robust structural stability. As expected, the Si/MXene composite architecture exhibits boosted sodium storage performance, in terms of an inspiring reversible capacity of 751 mAh·g^(-1)at 0.1 A·g^(-1), remarkable long-term cycling stability of 376 mAh·g^(-1)at 0.1 A·g^(-1) over 500 cycles, and outstanding rate capability(after one consecutive current density changing from 0.1 to 2.0 A·g^(-1), a large capacity of 275 mAh·g^(-1) is regained after suddenly returning the initial current density back to 0.1 A·g^(-1) and in the subsequent 200 cycles this composite architecture anode still delivers a capacity of 332 mAh·g^(-1)). The kinetics analysis indicates superior pseudocapacitive property, high electronic conductivity, and favorable sodium-ion adsorption and diffusion capability,confirming fast sodium storage performance. Impressively, ex-situ X-ray diffraction and selected area electron diffraction characterizations corroborate the formation of NaSi;as the main sodiation products during the reversible evolutions of cycled proceeding with sodium-ion insertion. This work sheds light on the elaborate design of silicon-based nanostructured anodes towards advanced high-performance sodium-ion batteries.
文摘A storage-efficient reconstruction framework for cartographic planar contours is developed.With a smaller number of control points,we aim to calculate the area and perimeter as well as to reconstruct a smooth curve.The input data forms an oriented contour,each control point of which consists of three values:the Cartesian coordinates(x,y)and tangent angleθ.Two types of interpolation methods are developed,one of which is based on an arc spline while the other one is on a cubic Hermite spline.The arc spline-based method reconstructs a G1 continuous curve,with which the exact area and perimeter can be calculated.The benefit of using the Hermite spline-based method is that it can achieve G2 continuity on most control points and can obtain the exact area,whereas the resulting perimeter is approximate.In a numerical experiment for analytically defined curves,more accurate computation of the area and perimeter was achieved with a smaller number of control points.In another experiment using a digital elevation model data,the reconstructed contours were smoother than those by a conventional method.
基金National Natural Science Foundation of China under Grant Nos.51639006 and 51725901
文摘Finite element（FE） is a powerful tool and has been applied by investigators to real-time hybrid simulations（RTHSs）. This study focuses on the computational efficiency, including the computational time and accuracy, of numerical integrations in solving FE numerical substructure in RTHSs. First, sparse matrix storage schemes are adopted to decrease the computational time of FE numerical substructure. In this way, the task execution time（TET） decreases such that the scale of the numerical substructure model increases. Subsequently, several commonly used explicit numerical integration algorithms, including the central difference method（CDM）, the Newmark explicit method, the Chang method and the Gui-λ method, are comprehensively compared to evaluate their computational time in solving FE numerical substructure. CDM is better than the other explicit integration algorithms when the damping matrix is diagonal, while the Gui-λ（λ = 4） method is advantageous when the damping matrix is non-diagonal. Finally, the effect of time delay on the computational accuracy of RTHSs is investigated by simulating structure-foundation systems. Simulation results show that the influences of time delay on the displacement response become obvious with the mass ratio increasing, and delay compensation methods may reduce the relative error of the displacement peak value to less than 5% even under the large time-step and large time delay.
文摘A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these non-uniform access behaviors,an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy,facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies,the approach excels at identifying and evicting infrequently used data,thereby optimizing cache utilization.The evaluation shows impressive performance improvement,especially on workloads with irregular access patterns.Benefiting from fine granularity,the proposal achieves superior storage efficiency compared with commonly used cache management schemes,providing a potential optimization opportunity for modern resource-constrained processors,such as spacecraft processors.Furthermore,the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications,enhancing their overall efficacy.
基金National Natural Science Foundation of China(NSFC)(12104358,12104361,12304406,12175168,12404390,92476105,92050103)Shaanxi Fundamental Science Research Project for Mathematics and Physics(22JSQ035,23JSQ014)Postdoctoral Fellowship Program ofChinaPostdoctoral Science Foundation(CPSF)(GZC20232118).
文摘Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum networks.
基金supported by the National Key Research and Development Program of China (Grant No.2023YFB4204000)National Key Research and Development Program of China (Grant No.2024YFB4206500)。
文摘In this study,the influence of the phase-change cooling storage system on integrating and controlling of the combined cooling,heating,and power system was analyzed through experiments and computational fluid dynamics simulations.The model of three-dimensional phase change material plate and cold storage tank was established and verified.The phase change material selected in this study is a eutectic salt with a phase change temperature of 8℃.The thermodynamic performance of the cold storage tank filled with phase change material plates was calculated,and the energy storage and release efficiency of the phase-change cooling storage system was analyzed.The results indicate that the phase change process correlates positively with the heat transfer fluid flow rate.The heat transfer fluid flow rates of 1.2 m^(3)/h,1.6 m^(3)/h,and 2.0 m^(3)/h all allow the phase change material within the encapsulation module to completely solidify within 8 hours;the flow rate required for melting is not less than 2.0 m^(3)/h,and the highest energy storage efficiency is up to 72%.Considering the thermodynamic performance of the phase-change cooling storage system,it is recommended to use a heat transfer fluid flow rate of 1.6 m^(3)/h for the cooling charge process and 2.0 m^(3)/h for the cooling release process.
基金support from the National Natural Science Foundation of China(Grant Nos.:52250010 and 52050128)the Natural Science Foundation of Jiangsu Province(Grant No.:BK20230086)+3 种基金L.P.acknowledges support from the National Natural Science Foundation of China(Grant No.:52201242)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)the Fund of Key Laboratory of Advanced Materials of Ministry of Education(No.AdvMat-2023-12)Z.M.S.acknowledges support from the National Natural Science Foundation of China(Grant No.:U23A20574).
文摘Cement-based materials are the foundation of modern buildings but suffer from intensive energy consumption.Utilizing cement-based materials for efficient energy storage is one of the most promising strategies for realizing zero-energy buildings.However,cement-based materials encounter challenges in achieving excellent electrochemical performance without compromising mechanical properties.Here,we introduce a biomimetic cement-based solid-state electrolyte(labeled as l-CPSSE)with artificially organized layered microstructures by proposing an in situ ice-templating strategy upon the cement hydration,in which the layered micropores are further filled with fast-ion-conducting hydrogels and serve as ion diffusion highways.With these merits,the obtained l-CPSSE not only presents marked specific bending and compressive strength(2.2 and 1.2 times that of traditional cement,respectively)but also exhibits excellent ionic conductivity(27.8 mS·cm^(-1)),overwhelming most previously reported cement-based and hydrogel-based electrolytes.As a proof-of-concept demonstration,we assemble the l-CPSSE electrolytes with cement-based electrodes to achieve all-cement-based solid-state energy storage devices,delivering an outstanding full-cell specific capacity of 72.2 mF·cm^(-2).More importantly,a 5×5 cm^(2) sized building model is successfully fabricated and operated by connecting 4 l-CPSSE-based full cells in series,showcasing its great potential in self-energy-storage buildings.This work provides a general methodology for preparing revolutionary cement-based electrolytes and may pave the way for achieving zero-carbon buildings.
基金supported by National Natural Science Foundation of China(grant nos.52327802,52303101,52173078,and 52130303)National Key R&D Program of China(no.2022YFB3805702).
文摘To meet the demands of the global energy transition,photothermal phase change energy storage materials have emerged as an innovative solution.These materials,utilizing various photothermal conversion carriers,can passively store energy and respond to changes in light exposure,thereby enhancing the efficiency of energy systems.Photothermal phase change energy storage materials show immense potential in the fields of solar energy and thermal management,particularly in addressing the intermittency issues of solar power.Their multifunctionality and efficiency offer broad application prospects in new energy technologies,construction,aviation,personal thermal management,and electronics.
基金financially supported by the Special Fund for Agro-scientific Research in the Public Interest in China(201303104 and 201503120)the earmarked fund for China Agriculture Research System(CARS-03-01-24)+1 种基金the Key Science and Technology Program of Shanxi Province,China(20140311008-3)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD23B04)
文摘Shortages and fluctuations in precipitation are influential limiting factors for the sustainable cultivation of rain-fed winter wheat on the Loess Plateau of China. Plastic film mulching is one of the most effective water management practices to improve soil moisture, and may be useful in the Loess Plateau for increasing soil water storage. A field experiment was conducted from July 2010 to June 2012 on the Loess Plateau to investigate the effects of mulching time and rates on soil water storage, evapotranspiration （ET）, water use efficiency （WUE）, and grain yield. Six treatments were conducted： （1） early mulching （starting 30 days after harvest） with whole mulching （EW）; （2） early mulching with half mulching （EH）; （3） early mulching with no mulching （EN）; （4） late mulching （starting 60 days after harvest） with whole mulching （LW）; （5） late mulching with half mulching （LH）; and （6） late mulching with no mulching （LN）. EW increased precipitation storage efficiency during the fallow periods of each season by 18.4 and 17.8%, respectively. EW improved soil water storage from 60 days after harvest to the booting stage and also outperformed LN by 13.8 and 20.9% in each growing season. EW also improved spike number per ha by 13.8 and 20.9% and grain yield by 11.7 and 17.4% during both years compared to LN. However, EW decreased WUE compared with LN. The overall results of this study demonstrated that EW could be a productive and efficient practice to improve wheat yield on the Loess Plateau of China.
基金financially supported by Jiangsu Water Science and Technology Program(Grant No.2018046 and 2019045).
文摘At present,water and fertilizer use efficiency is low in many cultivation areas in southern China.Studies show that the buried straw layer can effectively conserve water and fertilizer.To investigate the optimal irrigation upper limit above the straw barrier and its effect on soil moisture and nitrogen distribution,an indoor soil column experiment was conducted.Six treatments were designed consisting of two levels of straw layer i.e.,(with and without buried straw layer at 25 cm depth),and three irrigation water upper limits i.e.,(saturated moisture content(s),field water holding capacity(f),and 80%of field water holding capacity(0.8f)as the upper limit of irrigation).The result revealed that the buried straw layer can inhibit water infiltration and significantly increase the water storage capacity and water storage efficiency of 0-25 cm soil depth.Under the condition of no evaporation,when the upper limit of irrigation water does not exceed the field water holding capacity,the storage efficiency of 0-25 cm soil water reaches 89%-91%after 6 d.Moreover,a buried straw layer can inhibit the deep percolation of nitrate nitrogen and increase the amount of nitrate-nitrogen in 0-25 cm soil.The 80%field water holding capacity irrigation upper limit combined with straw interlayer treatment had a higher nitrate-nitrogen content in the 0-25 cm soil layer than other treatments.Therefore,80%of field water holding capacity as the upper limit of irrigation combined with buried straw layer is the optimal strategy to conserve soil water and nitrogen in the upper soil profile.
