Spatiotemporal phase change materials for thermal energy long-term storage and controllable release

Phase change materials(PCMs)have attracted much attention in the field of solar thermal utilization recently,due to their outstanding thermal energy storage performance.However,PCMs usually release their stored latent heat spontaneously as the temperature below the phase transition temperature,rendering thermal energy storage and release uncontrollable,thus hindering their practical application in time and space.Herein,we developed erythritol/sodium carboxymethylcellulose/tetrasodium ethylenediaminetetraacetate(ERY/CMC/EDTA-4Na)composite PCMs with novel spatiotemporal thermal energy storage properties,defined as spatiotemporal PCMs(STPCMs),which exhibit the capacity of thermal energy long-term storage and controllable release.Our results show that the composite PCMs are unable to lose latent heat due to spontaneous crystallization during cooling,but can controllably release thermal energy through cold crystallization during reheating.The cold-crystallization temperature and enthalpy of composite PCMs can be adjusted by proportional addition of EDTA-4Na to the composite.When the mass fractions of CMC and EDTA-4Na are both 10%,the composite PCMs can exhibit the optical coldcrystallization temperature of 51.7℃ and enthalpy of 178.1 J/g.The supercooled composite PCMs without latent heat release can be maintained at room temperature(10-25℃)for up to more than two months,and subsequently the stored latent heat can be controllably released by means of thermal triggering or heterogeneous nucleation.Our findings provide novel insights into the design and construction of new PCMs with spatiotemporal performance of thermal energy long-term storage and controllable release,and consequently open a new door for the development of advanced solar thermal utilization techniques on the basis of STPCMs.

Efficient Technique for Long-Term <i>in Vitro</i>Storage of Transgenic Aspen Genotypes

In vitro culture of isolated cells from tissues and organs is sometimes used to preserve and reproduce unique genotypes of woody plants. The technique, however, requires regular subculturing which raises storage costs and creates risks for contamination and accumulation of somaclonal variations. We examined the effects of sugar composition of culture medium, the length of photoperiod, light intensity, and ambient temperature on the survival of plant material in vitro. The study was performed on 49 genotypes of Populus tremula (46 transgenic genotypes carrying GFP-, Xeg- and Gus-genes, and 3 control (wild-type) genotypes). It was shown that effective storage of plants was achieved through optimization of the combined effects of all storage parameters under study. Based on the experimental data, we developed a protocol for long-term in vitro storage of desirable genotypes without subculture and with a survival rate of up to 98%. The best results were obtained when the plant material was pre-cultured on a WPM medium containing 15 g/L sucrose, 7.5 g/L sorbitol and 7.5 g/L mannitol, and then stored at +4°C under a 24-hour light day cycle with only 8 hours of light per day and maximum light intensity of 2000 lux. Post-storage recovery was done by culturing on a medium containing 1 mg/L gibberellic acid. The developed method can be used for effective in vitro storage of the studied genotypes for up to 24 months without subculture.

Cost Optimization Strategy for Long-Term Storage of Scientific Workflow

With the rapid development of cloud environment, the capabilities of systems have been promoted with powerful computing and storage. But for the characteristic of “pay-as-you-go” of cloud resources, it is necessary to consider the different data storage cost. Especially for processing of “old data” in longterm storage, an appropriate strategy is needed to reduce users’ cost. Considering the characteristics of price stratification in the current commercial cloud environment, a three-level price stratified storage strategy is proposed based on the CTT-SP algorithm, which stores part of the “old data” on relatively inexpensive secondary and tertiary storage, and ensures that the time delay caused by three-level storage does not exceed the deadline. Compared with other storage methods, the experimental result shows the strategy proposed can guarantee the time delay while reducing the cost of users significantly in longterm storage.

Multi-Time-Scale Resource Allocation Based on Long-Term Contracts and Real-Time Rental Business Models for Shared Energy Storage Systems

The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,and demand mismatch hinder their broader adoption.In response,shared energy storage systems(SESSs)offer a more cohesive and efficient use of ESS,providing more accessible and cost-effective energy storage solutions to overcome these obstacles.To enhance the profitability of SESSs,this paper designs a multi-time-scale resource allocation strategy based on long-term contracts and real-time rental business models.We initially construct a life cycle cost model for SESS and introduce a method to estimate the degradation costs of multiple battery groups by cycling numbers and depth of discharge within the SESS.Subsequently,we design various long-term contracts from both capacity and energy perspectives,establishing associated models and real-time rental models.Lastly,multi-time-scale resource allocation based on the decomposition of user demand is proposed.Numerical analysis validates that the business model based on long-term contracts excels over models operating solely in the real-time market in economic viability and user satisfaction,effectively reducing battery degradation,and leveraging the aggregation effect for SESS can generate an additional increase of 10.7%in net revenue.

Assessment of Fatigue Strength of An Offshore Floating Production and Storage Unit

The procedure of assessment of structural fatigue strength of an offshore floating production and storage and offloading unit (FPSO) in this paper. The emphasis is placed on the long-term prediction of wave induced loading, the refined finite element model for hot spot stress calculation, the combination of stress components, and fatigue damage assessment based on S-N curve.

Fast Solution Method for the Large-scale Unit Commitment Problem with Long-term Storage

Long-term storage(LTS)can provide various services to address seasonal fluctuations in variable renewable energy by reducing energy curtailment.However,long-term unit commitment(UC)with LTS involves mixed-integer programming with large-scale coupling constraints between consecutive intervals(state-of-charge(SOC)constraint of LTS,ramping rate,and minimum up/down time constraints of thermal units),resulting in a significant computational burden.Herein,an iterative-based fast solution method is proposed to solve the long-term UC with LTS.First,the UC with coupling constraints is split into several sub problems that can be solved in parallel.Second,the solutions of the sub problems are adjusted to obtain a feasible solution that satisfies the coupling constraints.Third,a decoupling method for long-term time-series coupling constraints is proposed to determine the global optimization of the SOC of the LTS.The price-arbitrage model of the LTS determines the SOC boundary of the LTS for each sub problem.Finally,the sub problem with the SOC boundary of the LTS is iteratively solved independently.The proposed method was verified using a modified IEEE 24-bus system.The results showed that the computation time of the unit combination problem can be reduced by 97.8%,with a relative error of 3.62%.

Particle Size Optimization of Thermochemical Salt Hydrates for High Energy Density Thermal Storage

Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and cost.Specifically,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy buildings.Thermochemical materials(TCMs)as a class of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high storage capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal storage.However,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of storage.In this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydrates during thermal cycling.This is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the composites.The model is experimentally validated on multiple TCM salt hydrates with different water content,and effect of Rcrit on hydration and dehydration kinetics is also investigated.

Long-term Coordination of Transmission and Storage to Integrate Wind Power

A power system with a high wind power integration requires extra transmission capacity to accommodate the intermittency inherent to wind power production.Storage can smooth out this intermittency and reduce transmission requirements.This paper proposes a stochastic optimization model to coordinate the long-term planning of both transmission and storage facilities to efficiently integrate wind power.Both longterm and short-term uncertainties are considered in this model.Long-term uncertainty is described via scenarios,while shortterm uncertainty is described via operating conditions.Garver’s 6-node system and a system representing Northwest China in 2030 are used to illustrate the proposed model.Results indicate that storage reduces transmission requirement and the overall investment,and allows the efficient integration of wind power.

Long-term storage of lipid-like nanoparticles for mRNA delivery

Lipid-like nanoparticles(LLNs)have been extensively explored for messenger RNA(mRNA)delivery in various biomedical applications.However,the long-term storage of these nanoparticles is still a challenge for their clinical translation.In this study,we investigated a series of conditions for the long-term storage of LLNs with encapsulation of mRNA.We evaluated the stability of LLNs with different concentrations of cryoprotectants(sucrose,trehalose or mannitol)under the conditions of freezing or lyophilization processes.Through in vitro and in vivo mRNA delivery studies,we identified the optimal storage condition,and found that the addition with 5%(w/v)sucrose or trehalose to LLNs could remain their mRNA delivery efficiency for at least three months in the liquid nitrogen storage condition.

Understanding and quantifying capacity loss in storage aging of Ah-level Li metal pouch cells

Promoting industry applications of high-energy Li metal batteries(LMBs)is of vital importance for accelerating the electrification and decarbonization of our society.Unfortunately,the time-dependent storage aging of Ah-level Li metal pouch cells,a ubiquitous but crucial practical indicator,has not yet been revealed.Herein,we first report the storage behaviors and multilateral synergistic aging mechanism of Ah-level NCM811jjLi pouch cells during the 120-day long-term storage under various conditions.Contrary to the conventional belief of Li-ion batteries with graphite intercalation anodes,the significant available capacity loss of 32.8%on average originates from the major electrolyte-sensitive anode corrosion and partial superimposed cathode degradation,and the irreversible capacity loss of 13.3%is essentially attributed to the unrecoverable interface/structure deterioration of NCM with further hindrance of the aged Li.Moreover,principles of alleviating aging have been proposed.This work bridges academia and industry and enriches the fundamental epistemology of storage aging of LMBs,shedding light on realistic applications of high-energy batteries.

Optical storage： an emerging option in long-term digital preservation

Long-term digital preservation is an important issue in data storage area. For years, magnetic media based solutions, such as tape and hard disk drive （HDD） based archive systems, monopolize the data archiving market due to their high capacity and low cost. However, in the era of big data, rapidly increasing volume, velocity, and variety of data set bring numerous challenges to the archive systems in various aspects, such as capacity, cost, performance, reliability, power consumption, and so on. In recent years, high capacity optical media, such as bluray discs （BDs） and holographic discs, emerge with the revival of optical storage. Due to the natural simple construction of the optical media, the archive systems based on those optical media, e.g., BD library, demonstrate attractive properties, such as cost per bit, reliability, power consumption, and so on, thus become feasible options in long-term digital preservation. In this paper, we reviewed and compared both the magnetic and optical media based solutions for long-term digital preservation, followed by a summarization on techniques to improve the optical media based archive system.

Highly Efficient Na+ Storage in Uniform Thorn Ball-Like α-MnSe/C Nanospheres

Because of its high theoretical capacity,MnSe has been identified as a promising candidate as the anode material for sodiumion batteries.However,its fast capacity deterioration due to the huge volume change during the intercalation/deintercalation of sodium ions severely hinders its practical application.Moreover,the sodium storage mechanism of MnSe is still under discussion and requires in-depth investigations.Herein,the unique thorn ball-likeα-MnSe/C nanospheres have been prepared using manganese-containing metal organic framework(Mn-MOF)as a precursor followed by in situ gas-phase selenization at an elevated temperature.When serving as the anode material for sodium-ion battery,the as-preparedα-MnSe/C exhibits enhanced sodium storage capabilities of 416 and 405 mAh g^(-1)at 0.2 and 0.5 A g^(-1)after 100 cycles,respectively.It also shows a superior capacity retention of 275 mA h g^(-1)at 10 A g^(-1)after 2000 cycles,and a rate performance of 279 mA h g^(-1)at 20 A g^(-1).Such sodium storage properties could be attributed to the unique structure offering a highly efficient Na+diffusion kinetics with a diffusion coefficient between 1×10^(-11) and 3×10^(-10) cm^(2) s-1.The density functional theory calculation indicates that the fast Na+diffusion mainly takes place on the(100)plane of MnSe along a V-shaped path because of a relatively low diffusion energy barrier of 0.15 eV.

“Teaching old dogs new tricks”:targeting neural extracellular matrix for normal and pathological aging-related cognitive decline

Cognitive decline is a feature of normal and pathological aging. As the proportion of the global aged population continues to grow, it is imperative to understand the molecular and cellular substrates of cognitive aging for therapeutic discovery. This review focuses on the critical role of neural extracellular matrix in the regulation of neuroplasticity underlying learning and memory in another under-investigated "critical period": the aging process. The fascinating ideas of neural extracellular matrix forming a synaptic cradle in the tetrapartite synapse and possibly serving as a substrate for storage of very long-term memories will be introduced. We emphasize the distinct functional roles of diffusive neural extracellular matrix and perineuronal nets and the advantage of the coexistence of two structures for the adaptation to the ever-changing external and internal environments. Our study of striatal neural extracellular matrix supports the idea that chondroitin sulfate proteoglycan-associated extracellular matrix is restrictive on synaptic neuroplasticity, which plays important functional and pathogenic roles in early postnatal synaptic consolidation and aging-related cognitive decline. Therefore, the chondroitin sulfate proteoglycan-associated neural extracellular matrix can be targeted for normal and pathological aging. Future studies should focus on the cell-type specificity of neural extracellular matrix to identify the endogenous, druggable targets to restore juvenile neuroplasticity and confer a therapeutic benefit to neural circuits affected by aging.

How old is too old? In vivo engraftment of human peripheral blood stem cells cryopreserved for up to 18 years-implications for clinical transplantation and stability programs

BACKGROUND Peripheral blood stem cells(PBSC)are commonly cryopreserved awaiting clinical use for hematopoietic stem cell transplant.Long term cryopreservation is commonly defined as five years or longer,and limited data exists regarding how long PBSC can be cryopreserved and retain the ability to successfully engraft.Clinical programs,stem cell banks,and regulatory and accrediting agencies interested in product stability would benefit from such data.Thus,we assessed recovery and colony forming ability of PBSC following long-term cryopreservation as well as their ability to engraft in NOD/SCID/IL-2 Rγnull(NSG)mice.AIM To investigate the in vivo engraftment potential of long-term cryopreserved PBSC units.METHODS PBSC units which were collected and frozen using validated clinical protocols were obtained for research use from the Cellular Therapy Laboratory at Indiana University Health.These units were thawed in the Cellular Therapy Laboratory using clinical standards of practice,and the pre-freeze and post-thaw characteristics of the units were compared.Progenitor function was assessed using standard colony-forming assays.CD34-selected cells were transplanted into immunodeficient mice to assess stem cell function.RESULTS Ten PBSC units with mean of 17 years in cryopreservation(range 13.6-18.3 years)demonstrated a mean total cell recovery of 88%±12%(range 68%-110%)and post-thaw viability of 69%±17%(range 34%-86%).BFU-E growth was shown in 9 of 10 units and CFU-GM growth in 7 of 10 units post-thaw.Immunodeficient mice were transplanted with CD34-selected cells from four randomly chosen PBSC units.All mice demonstrated long-term engraftment at 12 wk with mean34%±24%human CD45+cells,and differentiation with presence of human CD19+,CD3+and CD33+cells.Harvested bone marrow from all mice demonstrated growth of erythroid and myeloid colonies.CONCLUSION We demonstrated engraftment of clinically-collected and thawed PBSC following cryopreservation up to 18 years in NSG mice,signifying likely successful clinical transplantation of PBSC following long-term cryopreservation.

Rocking-chair ammonium ion battery with high rate and long-cycle life

Aqueous rechargeable ammonium-ion batteries(AIBs)have drew considerable attention because of their capacity for high rates,low cost,and high safety.However,developing desired electrodes requiring stable structure in the aqueous fast ammoniation/de-ammoniation becomes urgent.Herein,an ammonium ion full battery using Cu_(3)[Fe(CN)_(6)]_(2)(CuHCF)acting to be a cathode and barium vanadate(BVO)acting to be an anode is described.Its excellent electrochemical behavior of Prussian blue analogs and the perfectly matched lattice structure of NH_(4)^(+)is expected.And the open structure of vanadium compounds satisfies the fast ammoniation/de-ammoniation of NH4+is also achieved.As a result of these synergistic effects,the BVO//CuHCF full cell retains 80.5 percent of its capacity following 1000 cycling.These achievements provide new ideas for developing low-cost and long-life AIBs.

Optimization of Urban Multi-energy Flow Systems Considering Seasonal Peak Shaving of Natural Gas

In order to alleviate the shortage of natural gas supply in winter,relevant policies have been issued to promote the construction of gas peak-shaving and storage facilities.Largescale gas storage can transfer the supply-demand relationship of natural gas in time sequence,which has great potential in improving the economy and reliabillity of urban multi-energy flow systems.Addressing this issue,this paper proposes a mid-and long-term energy optimization method for urban multi-energy flow system that considers seasonal peak shaving of natural gas.First,the energy supply and demand features of different energy subsystems are analyzed.Then,a network model of the electricity-gas-heat multi-energy flow system is established.Considering the time-of-use electricity price mechanism and the seasonal fluctuations of the natural gas price,a mid-and long-term energy optimization model maximizing the annual economic revenue is established.The alternative direction multiplier method with Gaussian back substitution(ADMM-GBS)algorithm is used to solve the optimal dispatch model.Finally,the proposed method is verified by employing the actual data of the demonstration zone in Yangzhong City,China.The simulation results show that the proposed method is effective.