Regulation of Lithium-Ion Flux by Nanotopology Lithiophilic Boron-Oxygen Dipole in Solid Polymer Electrolytes for Lithium-Metal Batteries

Inhomogeneous lithium-ion(Li^(+))deposition is one of the most crucial problems,which severely deteriorates the performance of solid-state lithium metal batteries(LMBs).Herein,we discovered that covalent organic framework(COF-1)with periodically arranged boron-oxygen dipole lithiophilic sites could directionally guide Li^(+)even deposition in asymmetric solid polymer electrolytes.This in situ prepared 3D cross-linked network Poly(ACMO-MBA)hybrid electrolyte simultaneously delivers outstanding ionic conductivity(1.02×10^(-3)S cm^(-1)at 30°C)and excellent mechanical property(3.5 MPa).The defined nanosized channel in COF-1 selectively conducts Li^(+)increasing Li^(+)transference number to 0.67.Besides,The COF-1 layer and Poly(ACMO-MBA)also participate in forming a boron-rich and nitrogen-rich solid electrolyte interface to further improve the interfacial stability.The Li‖Li symmetric cell exhibits remarkable cyclic stability over 1000 h.The Li‖NCM523 full cell also delivers an outstanding lifespan over 400 cycles.Moreover,the Li‖LiFePO_(4)full cell stably cycles with a capacity retention of 85%after 500 cycles.the Li‖LiFePO_(4)pouch full exhibits excellent safety performance under pierced and cut conditions.This work thereby further broadens and complements the application of COF materials in polymer electrolyte for dendrite-free and high-energy-density solid-state LMBs.

减缓自由阴离子迁移以缓解浓差极化用于高性能的聚合物锂金属电池

Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries(LMBs).Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the growth of lithium dendrites. Although single-ion conductor polymers(SICP) have been developed to reduce concentration polarization, the poor ionic conductivity caused by low carrier concentration limits their application. Herein, a dual-salt quasi-solid polymer electrolyte(QSPE), containing the SICP network as a salt and traditional dual-ion lithium salt, is designed for retarding the movement of free anions and simultaneously providing sufficient effective carriers to alleviate concentration polarization. The dual salt network of this designed QSPE is prepared through in-situ crosslinking copolymerization of SICP monomer, regular ionic conductor, crosslinker with the presence of the dual-ion lithium salt,delivering a high lithium-ion transference number(0.75) and satisfactory ionic conductivity(1.16 × 10^(-3) S cm^(-1) at 30 ℃). Comprehensive characterizations combined with theoretical calculation demonstrate that polyanions from SICP exerts a potential repulsive effect on the transport of free anions to reduce concentration polarization inhibiting lithium dendrites. As a consequence, the Li||LiFePO_4 cell achieves a long-cycle stability for 2000 cycles and a 90% capacity retention at 30 ℃. This work provides a new perspective for reducing concentration polarization and simultaneously enabling enough lithiumions migration for high-performance polymer LMBs.

Model-free Demand Response Scheduling Strategy for Virtual Power Plants Considering Risk Attitude of Consumers

Driven by modern advanced information and communication technologies,distributed energy resources have great potential for energy supply within the framework of the virtual power plant(VPP).Meanwhile,demand response(DR)is becoming increasingly important for enhancing the VPP operation and mitigating the risks associated with the fluctuation of renewable energy resources(RESs).In this paper,we propose an incentivebased DR program for the VPP to minimize the deviation penalty from participating in the power market.The Markov decision process(MDP)with unknown transition probability is constructed from the VPP’s prospective to formulate an incentivebased DR program,in which the randomness of consumer behavior and RES generation are taken into consideration.Furthermore,a value function of prospect theory(PT)is developed to characterize consumer’s risk attitude and describe the psychological factors.A model-free deep reinforcement learning(DRL)-based approach is proposed to deal with the randomness existing in the model and adaptively determine the optimal DR pricing strategy for the VPP,without requiring any system model information.Finally,the results of cases tested demonstrate the effectiveness of the proposed approach.

支柱策略增强离子传输和结构稳定性的KVPO4F用于超稳定的钾离子电池正极

近年来,由于丰富的钾资源储量和低廉的价格,钾离子电池在大规模储能领域表现出极大的应用前景.开发具有高安全性、高能量密度、低成本、长寿命的正极材料是推动钾离子电池实用化的关键.KVPO4F(KVPF)因其工作电压高、能量密度高、热稳定性好,被认为是一种很有前途的钾离子电池正极材料.然而,由于大半径的钾离子反复脱出/嵌入导致较慢的动力学和大的体积变化,从而影响材料循环稳定性.本文通过将大半径铯离子引入KVPF结构中的“支柱”策略,可有效提高材料的离子传导特性,并改善充放电过程中材料的结构稳定性,从而实现铯掺杂的KVPF正极优异的储钾性能.同时,高循环稳定性的KVPF//石墨全电池也展示了其在钾离子电池中巨大的实际应用潜力.

Whole-soil warming shifts species composition without affecting diversity,biomass and productivity of the plant community in an alpine meadow

The structure and function of plant communities in alpine meadow ecosystems are potentially susceptible to climate warming.Here,we utilized a unique field manipulation experiment in an alpine meadow on the Qinghai-Tibetan Plateau and investigated the responses of plant species diversity,composition,biomass,and net primary productivity(NPP)at both community and functional group levels to whole-soil-profile warming(3–4℃ across 0–100 cm)during 2018–2021.Plant species diversity,biomass and NPP(both above-and belowground)at the community level showed remarkable resistance to warming.However,plant community composition gradually shifted over time.Over the whole experimental warming period,aboveground biomass of legumes significantly decreased by 45%.Conversely,warming significantly stimulated aboveground biomass of forbs by 84%,likely because of better growth and competitive advantages from the warming-induced stimulation of soil water and other variables.However,warming showed minor effects on aboveground biomass of grasses and sedges.Overall,we emphasize that experimental warming may significantly affect plant community composition in a short term by triggering adjustments in plant interspecific competition or survival strategies,which may cause potential changes in plant productivity over a more extended period and lead to changes in carbon source-sink dynamics in the alpine meadow ecosystem.

Hybrid Energy Sharing Mechanism for Integrated Energy Systems Based on the Stackelberg Game

Integrating the sharing economy and the power industry is of positive significance for the development of the energy market.With the energy market transforming from a traditional vertical structure to an interactive and competitive structure,users'roles need to change,along with supply and demand interacting more frequently.Thus,the traditional centralized optimization method for a single energy source can hardly reveal the complex multi-entity behavior of multi-energy coupling.Therefore,this paper establishes a distributed electrical-gas-thermal energy sharing mechanism centered on an energy hub that can converse energy,and build a more applicable integrated energy system body.First,the supply-demand interaction and the energy conversion process is constructed with reference to the operationa丨mode of’a sharing economy and the dual role of prosumers.A Stackelberg model is established with the integrated energy system operator as the leader and prosumers as the followers,to simultaneously optimize the profit of the leader in the upper level and the comfort of the fo!lowers,energy use and utility in the lower level.Furthermore,for protecting the participants’privacy,a distributed algorithm is used to find the optimal solution to equilibrate the model,and the existence and uniqueness of the solution is proved.Finally,a case study validates the effectiveness of the hybrid energy sharing mechanism and provides a reference for the integration of the energy sharing economy with the integrated energy system.

Synergistic effects in Mn-Co mixed oxide supported on cordierite honeycomb for catalytic deep oxidation of VOCs

A series of Co-Mn mixed oxide catalyst supported on a cordierite monolith was facilely synthesized by ultrasonic impregnation.Its catalytic performance was evaluated in the combustion of toluene,ethyl acetate and its mixture.It was observed that with incorporating Mn into Co_(3)O_(4),the formation of solid solution with spinel structure could significantly improve the catalytic activity of pure phase Co_(3)O_(4).And the monolithic Co_(0.67)Mn_(0.33)O_(x) catalyst showed the best catalytic performance in the catalytic oxidation of toluene and ethyl acetate which could be completely oxidized at 220 and 180℃ respectively under the reaction velocity(WHSV)about 45,000 m L/(g·hr)and pollutant concentration of 500 ppm V.The total conversion temperature of the VOCs mixture was at 230℃(500 ppm V toluene and 500 ppm V ethyl acetate)and determined by the temperature at which the most difficult molecule was oxidized.The excellent catalytic performance of monolithic Co_(0.67)Mn_(0.33)O_(x) was attributed to the higher content of Mn^(3+),Co^(3+),surface adsorbed oxygen and better redox ability.The prepared catalyst showed the good mechanical stability,reaction stability,and good adaptability to different reaction conditions.

Blue revolution for food security under carbon neutrality: A case from the water-saving and drought-resistance rice

The increasing concentration of greenhouse gases(GHGs)in Earth's atmosphere leads to global warming,which further causes a series of climate changes and does great harm to both human society and natural ecosystems.Agricultural GHG emissions,mainly in theform of methane(CH4)and nitrous oxide(N2O),areasignificantsourceofGHGs,accountingfor~14%total global GHGs(Zhang et al.,2022).One major source of agricultural GHGs is CH4 emissions from rice paddies,which is responsiblefor~10%-12%ofhuman-inducedCH4emissions(van Groenigen et al.,2013)and contributes~2.40%to the enhanced global warming effect(Zhang et al.,2022).The global warming potential of GHGs emissions from rice systems is roughly four times higher than either wheat or maize(Linquist et al.,2012).

A Decoupling Control Model on Perturbation Method for Twin-Roll Casting Magnesium Alloy Sheet

To better understand the twin-roll casting process,based on the analysis of the solidification phenomenon,the geometry shape of the molten metal pool,the continuity of metal and the balance of energy and momentum,five critical partial equations were established separately including the equations of pool level,solidification process,roll separating force,roll gap and casting speed.Meanwhile,to obtain a uniform sheet thickness and keep a constant roll separating force,a decoupling control model was built on the perturbation method to eliminate the interference of process parameters.The simulation results show that the control model is valuable to quickly and accurately determine the control parameters.Moreover,Mg alloy sheets with high quality were cast by applying this model.

All in one theranostic nanoplatform enables efficient anti-tumor peptide I delivery for triple-modal imaging guided cancer therapy

Developing a reliable system to efficiently and safely deliver peptide drugs into tumor tissues still remains a great challenge since the instability of peptide drugs and low ability to traverse the cell membrane. Herein, we constructed a multifunctional nanoplatform based on porous europium/gadolinium (Eu/Gd)-doped NaLa(MoO4)2 nanoparticles (NLM NPs) to deliver antitumor peptide of B-cell lymphoma/leukemia-2-like protein 11 (BIM) for cancer therapy. The porous NLM NPs exhibited inherent photoluminescent, magnetic and X-ray absorbable properties, which enable them for triple-modal bioimaging, including fluorescence, magnetic resonance imaging (MRI) and computed tomography (CT). This triple-modal bioimaging can contribute to monitoring NLM NPs biodistribution and guiding therapy in vitro and in vivo. Furthermore, the NLM NPs showed negligible cytotoxicity in vitro and tissue toxicity in vivo. Importantly, NLM NPs could load the antitumor peptide of BIM and efficiently improve the resistance of peptide drugs to proteolysis. The BIM peptide was efficiently delivered into the tumor cells by NLM NPs, which can inhibit the growth and promote the apoptosis of cancer cells in vitro, significantly inhibit the tumor growth in vivo. Notably, NLM-BIM theranostic nanoplatform exhibits low systemic toxicity and fewer side effects in vivo. The NLM NPs can serve as a promising multifunctional peptide delivery nanoplatform for multi-modal bioimaging and cancer therapy.

Network-Constrained Energy Consumption Game for Dynamic Pricing Markets

The electricity distribution network is experiencing a profound transformation with the concept of the smart grid,providing possibilities for selfish consumers to interact with the distribution system operator(DSO)and to maximize their individual energy consumption utilities.However,this profitseeking behavior among consumers may violate the network constraints,such as line flows,transformer capacity and bus voltage magnitude limits.Therefore,a network-constrained energy consumption(NCEC)game among active load aggregators(ALAs)is proposed to guarantee the safety of the distribution network.The temporal and spatial constraints of an ALA are both considered,which leads the formulated model to a generalized Nash equilibrium problem(GNEP).By resorting to a well-developed variational inequality(VI)theory,we study the existence of solutions to the NCEC game problem.Subsequently,a two-level distributed algorithm is proposed to find the variational equilibrium(VE),a fair and stable solution to the formulated game model.Finally,the effectiveness of the proposed game model and the efficiency of the distributed algorithm are tested on an IEEE-33 bus system.

Rational design of eco-friendly Mn-doped nonstoichiometric CuInSe/ZnSe core/shell quantum dots for boosted photoelectrochemical efficiency

Colloidal core/shell quantum dots(QDs)with environment-friendly feature and controllable optoelectronic properties are promising building blocks in emerging solar technologies.In this work,we rationally design and tailor the eco-friendly CuInSe(CISe)/ZnSe core/shell QDs by Mn doping and stoichiometric optimization(i.e.,molar ratios of Cu/In).It is demonstrated that Mn doping in In-rich CISe/ZnSe core/shell QDs can effectively engineer the charge kinetics inside the QDs,enabling efficient photogenerated electrons transfer into the shell for retarded charge recombination.As a result,a solar-driven photoelectrochemical(PEC)device fabricated using the optimized Mn-doped In-rich CISe/ZnSe core/shell QDs(Cu/In ratio of 1/2)exhibits improved charge extraction and injection,showing a~3.5-fold higher photocurrent density than that of the pristine CISe/ZnSe core/shell QDs under 1 sun AM 1.5G illumination.The findings indicate that transition metal doping in“green”nonstoichiometric core/shell QDs may offer a new strategy for achieving high-efficiency solar energy conversion applications.

Rare-earth-incorporated low-dimensional chalcogenides: Dry-method syntheses and applications

Chalcogenide thin films incorporating rare-earth (RE) elements with applicationsin optics, electronics, and magnetics have received considerable attention.Aiming at growing pure chalcogenides, dry-method syntheses have beendeveloped. In this review, we summarize the progress thus far on lowdimensionalRE-based chalcogenides (RECs), covering fabrication methods,structures, and applications. This review also provides the summary and perspectivesof the challenges of fabrication and opportunities on the applicationof RECs in the future.

Extended endoscopic endonasal approach for pituitary adenoma: a single-center experience of 171 patients

Background: Pituitary adenoma (PA) is a common intracranial tumor and surgical treatment is considered to be the best treatment for most patients. The extended endoscopic endonasal approach (EEEA) has been used to treat increasing numbers of patients with PA in recent years. We conducted this study to evaluate the safety and efficacy of this approach for PA resection. Methods: We performed a retrospective analysis of all patients who underwent an EEEA to remove PA by a binostril, four-handed technique between October 2013 and April 2016 in our department. The medical information of the patients including gender, age, tumor size, hormone level, clinical outcome, and complications were collected and analyzed.Results: From a total of 593 pituitary adenoma surgeries, 171 patients (101 male and 70 female, mean age 47.4 ± 12.8 years) underwent EEEA, including 96 with functional adenomas (56.14%) and 75 with nonfunctional adenomas (43.86%). The most common symptoms were headache and vision change. Gross total resection was achieved in 126 patients (73.68%). Common complications were hyposmia or anosmia, diabetes insipidus, hypopituitarism, postoperative cerebrospinal fluid leak, cerebral hemorrhage, and epistaxis. The mean duration of follow-up was 14.6 months (range: 6–31 months). Conclusions: The application of EEEA for PA resection by a binostril, four-handed technique provided great surgical freedom with minimal invasion, and resulted in few complications. EEEA is a secure and effective surgical method that could be used for the majority of PAs.

Dynamically observing the formation of MOFs-driven Co/N-doped carbon nanocomposites by in-situ transmission electron microscope and their application as high-efficient microwave absorbent

Metal-organic frameworks(MOFs)derived magnetic carbon-based nanocomposites have drawn widespread attentions due to the well distributed nanocrystals in carbon matrix.Dynamically observing the formation process is urgently needed.Herein,taking zeolitic imidazolate framework(ZIF)-67 as an example,the pyrolysis process is investigated by in-situ transmission electron microscopy(TEM)assisted with ex-situ characterizations.Co nanocrystals are evenly distributed in carbon at the initial stage of carbonization.By increasing pyrolysis temperature,the nanocrystals grow bigger and migrate to carbon surface.The carbon texture transfers from amorphous to crystalline at 600°C,and thoroughly converts at 800°C.In-situ heating TEM shows that more tiny Co nanocrystals move out from the carbon texture by increasing temperature from 700 to 800°C.At 1,000°C,some escaped tiny Co nanocrystals are volatilized and disappeared.The residual escaped Co nanocrystals catalyze the formation of carbon nanotubes(CNTs).Due to the synergistic effect between Co and carbon as well as porous structure,the nanocomposites show high-efficient microwave absorption performance,which can be tuned by pyrolysis temperature,heating rate,and mass fraction.When the mass fraction is 30 wt.%,the nanocomposites obtained at 600 or 700°C display remarkable microwave absorption with optimal reflection loss(RL)smaller than−70 dB and effective absorption band larger than 4.9 GHz.Combining the in-situ and ex-situ techniques,some key findings were observed:(1)graphitization of carbon;(2)volatilization of Co nanocrystals;(3)formation process of CNTs by Co catalyst.These findings are helpful to understand the formation of MOFs derived carbon-based composites and expand their practical applications,especially for microwave absorption.