V2O5 Nanospheres with Mixed Vanadium Valences as High Electrochemically Active Aqueous Zinc-Ion Battery Cathode

AV4+-V2O5 cathode with mixed vanadium valences was prepared via a novel synthetic method using VOOH as the precursor,and its zinc-ion storage performance was evaluated.The products are hollow spheres consisting of nanoflakes.The V4+-V2O5 cathode exhibits a prominent cycling performance,with a specific capacity of 140 mAhg-1 after 1000 cycles at 10 A g.1,and an excellent rate capability.The good electrochemical performance is attributed to the presence of V4+,which leads to higher electrochemical activity,lower polarization,faster ion diffusion,and higher electrical conductivity than V2O5 without V4+.This engineering strategy of valence state manipulation may pave the way for designing high-performance cathodes for elucidating advanced battery chemistry.

Molecular cloning and expression under abiotic stresses and hormones of the ethylene response factor Ⅶ gene FmRAP2.12 from Fraxinus mandshurica

RELATED TO AP2.12(RAP2.12)is one of the Ethylene Response Factors(ERF)transcription factor and plays a key role in controlling plant root bending and responding to multiple abiotic stresses including hypoxia stress.In this study,FmRAP2.12 gene was isolated and characterized from Fraxinus mandshurica Rupr.The open reading frame(ORF)of FmRAP2.12 was 1170 bp and encoded a protein of 389 amino acids.The conserved domains,three-dimensional phylogenetic relationship of FmRAP2.12 was also investigated.Quantitative real-time(qRT-PCR)analyzed the expression of FmRAP2.12 in different tissues.The expression level of FmRAP2.12 was highest in roots followed by leaves,and lowest in male flowers.Abiotic stress and hormone signal-induced expression was established using qRT-PCR.Salt stress induced FmRAP2.12 to a double peak pattern:the first peak value was at 6 h and the second at 72 h.Drought stress also induced FmRAP2.12 to a double peak pattern:the first at6 h and the second at 48 h.FmRAP2.12 was up-regulated after initiation of gibberellic acid(GA3)treatment,with a one peak pattern at 24 h.FmRAP2.12 may not respond to cold stress and Abscisic acid(ABA)treatment.The transient overexpression of FmRAP2.12 caused the up-expression of downstream key genes of abiotic stress response and gibberellin pathway.Our research reveals the molecular characteristic and expression patterns under abiotic stress and hormone condition of FmRAP2.12,providing support for the genetic improvement of F.mandshurica at a molecular level.

Relationship of tropical cyclone size change rate with size and intensity over the western North Pacific

In this study,the relationship of tropical cyclone(TC)size change rate(SCR),within 24 hours,with size,intensity,and intensity change rate(ICR)are explored over the western North Pacific.TC size is defined as the azimuthally averaged radius of gale-force wind of 17 m s−1(R17)based on the Multiplatform Tropical Cyclone Surface Winds Analysis data.The majority of SCRs are mainly distributed in the range from−20 to 80 km d−1.The correlation coefficients between SCR and size(SCR-R17),intensity,and ICR(SCR-ICR)are−0.43,−0.12,and 0.25,respectively.The sensitivity of the SCR-R17 and SCR-ICR relationships to size,intensity,and evolution stage are further examined.Results show that the SCR-R17 relationship is more sensitive to variations of size and evolution stage than that of intensity.The relationship of SCR-ICR is largely modulated by the evolution stage.The correlation coefficient of SCR-ICR can increase from 0.25 to 0.40 when only considering the lifetime stages concurrently before and after the lifetime maximum size(LMS)and lifetime maximum intensity.This demonstrates that ICR is a potential factor in predicting SCR during these evolution stages.Besides,the TC size expansion(shrinkage)is more likely to occur for TCs with smaller(larger)size and weaker(stronger)intensity.The complexity of size change during a TC's lifetime can be attributed to the fact that shrinkage or expansion could occur both before and after LMS.

四苯乙烯基共价有机框架的设计、合成及应用

共价有机框架(COFs)作为一类新型的结晶多孔材料,是由构筑单元通过共价键自组装而成。COFs具有孔道规整、热稳定性高、结晶度高、结构可调等特点,因此在气体存储与分离、催化、质子传导、储能材料、光电、传感以及生物医学等领域具有广泛的应用。近年来,四苯乙烯基共价有机框架(TPE-based COFs)因其聚集诱导发光效应明显、合成简单、易功能化而备受关注。本文简述了四苯乙烯基COFs的构筑单元、拓扑结构、合成策略,以及其在不同领域的应用进展。最后指出了四苯乙烯基COFs的发展前景以及可能面临的挑战。

Light-Mediated Spatiotemporally Dynamic Assembly of DNA Nanostructures in Living Cells Regulates Autophagy

The assembly of exogenous artificial architectures inside cells can regulate a series of biological events,which heavily relies on the development of spatiotemporally controlled molecular assembly systems.We herein report a designer deoxyribonucleic acid(DNA)nanostructure that enables light-mediated spatiotemporally dynamic assembly in living cells and consequently achieves efficient regulation of cell autophagy.The DNA nanostructure was constructed from i-motif moiety-containing branched DNA,photocleavable bond-containing linker,and tumor cell-targeting aptamer.After cellular uptake mediated by aptamers,under the spatiotemporal control of both UV light and late endosomal/lysosomal acidic environments,disassembly/reassembly of DNA nanostructure occurred via two rationally designed routes,generating microsized DNA assembly.As a result,autophagy was significantly enhanced with the increase of DNA assembly size.The enhanced autophagy showed an impact on related biological effects.Our system is expected to be a powerful tool for the regulation of intracellular events and cellular behaviors.

Comprehensive evaluation of the optimal rates of irrigation and potassium application for strawberry

Accurate and effective management of irrigation and fertilization is essential for efficient greenhouse strawberry production.Here,the effects of the combined application of water and potassium on strawberry growth were evaluated by experimenting with 12 treatments,including four transpiration(ET_(c))-based irrigation levels(W1:100%ET_(c),W2:85%ET_(c),W3:70%ET_(c),and W4:55%ET_(c))and three potassium levels according to the target yield(K1:369.5 kg/hm^(2),K2:307.9 kg/hm^(2),and K3:246.3 kg/hm^(2)).Various indexes of strawberry yield,fruit quality,water and fertilizer utilization efficiency,and soil nutrient residues were measured.Irrigation and potassium application had significant effects on strawberry production.Higher irrigation levels increased yield(Y),and moderate water and potassium application increased single fruit weight(SFW),water utilization efficiency(WUE),total soluble sugar(TSSC),and the sugar-acid ratio(SAR).While low-application of potassium increased the soluble protein content(SP),partial factor productivity of potassium(PFP_(K)),and reduce nutrient residues in soil effectively.A comprehensive system for evaluating strawberry growth and its benefits to the soil environment was developed.The FAHP and CRITIC methods were used to calculate the subjective weight and objective weight of each index,respectively.The largest subjective weight was observed forY(0.200),and the largest objective weight was observed for soil-available potassium(0.101).The final weight was determined using Game theory;Y had the highest weight(0.185),and free amino acids(FAA)had the lowest weight(0.047).Grey relational analysis(GRA)was used to evaluate the optimal irrigation and potassium scheme for accomplishing multiple objectives.The response of the comprehensive score of strawberries to irrigation and potassium exhibited a negative parabolic relationship,and the effect of irrigation was greater than the effect of potassium application.There was a significant interaction between irrigation and potassium application,and an irrigation amount of 2053-2525 m^(3)/hm^(2) with a potassium application rate of 288.1-334.2 kg/hm^(2) was optimal for promoting strawberry yield,fruit quality,and efficiency and reducing soil nutrient residues.The results of this study provide new insights that could aid the development of sustainable approaches for enhancing agricultural production.

Interfacial adsorption-insertion mechanism induced by phase boundary toward better aqueous Zn-ion battery

Biphasic and multiphasic compounds have been well clarified to achieve extraordinary electrochemical properties as advanced energy storage materials.Yet the role of phase boundaries in improving the performance is remained to be illustrated.Herein,we reported the biphasic vanadate,that is,Na_(1.2)V_(3)O_(8)/K_(2)V_(6)O_(16)·1.5H_(2)O(designated as Na0.5K0.5VO),and detected the novel interfacial adsorption-insertion mechanism induced by phase boundaries.Firstprinciples calculations indicated that large amount of Zn^(2+)and H^(+)ions would be absorbed by the phase boundaries and most of them would insert into the host structure,which not only promote the specific capacity,but also effectively reduce diffusion energy barrier toward faster reaction kinetics.Driven by this advanced interfacial adsorption-insertion mechanism,the aqueous Zn/Na_(0.5)K_(0.5)VO is able to perform excellent rate capability as well as long-term cycling performance.A stable capacity of 267 mA h g^(-1)after 800 cycles at 5 A g^(-1)can be achieved.The discovery of this mechanism is beneficial to understand the performance enhancement mechanism of biphasic and multiphasic compounds as well as pave pathway for the strategic design of highperformance energy storage materials.

Up-conversion fluorescence biosensor for sensitive detection of CA-125 tumor markers

Sensitive and specific bioassays of tumor markers are critical for early cancer detection and treatment.In recent years,lanthanide(Ln3+)doped upconversion nanoparticles(UCNPs)have attracted wide attentions in tumor markers detectio n.Herein,we co mbined NaYF4:Yb,Tm and silver nanoparticles,serving as energy donor and receptor,respectively,to form an up-conversion fluorescence based inhibitory tumor marker biosensor system.The tumor marker CA-125 molecules are labeled with silver NPs,and the energy transfer fluorescent signal can be detected between the UCNPs and the silver NP receptors.The biosensor shows good stability,high sensitivity and selectivity in the tumor marker concentration range from 5 to 100 ng/mL,as well as a detection limit of 120 pg/mL.Due to the advantage of ease of fabrication and operation,low cost and high information capacity,this technology holds great potential for the clinical applications.

Simultaneous regulation of cations and anions in an electrolyte for high-capacity, high-stability aqueous zinc–vanadium batteries

Safe,inexpensive aqueous zinc-ion batteries(AZIBs)are regarded as promising energy storage devices.However,they still face issues,including dissolution and collapse of the cathode as well as H_(2)evolution and the growth of Zn dendrites on the Zn anode.Herein,we simultaneously regulate the cations and anions in the electrolyte for high-capacity,high-stability aqueous zinc–vanadium(Zn–V)batteries based on a bimetallic cation-doped Na_(0.33)K_(0.1)V_(2)O_(5)·nH_(2)O cathode.We demonstrate that Na^(+) cations suppress cathode dissolution and restrain Zn dendrite growth on the anode via an electrostatic shield effect.We also illustrate that ClO_(4)^(-) anions participate in energy storage at the cathode and are reduced to Cl^(-),generating a protective layer on the Zn anode surface and providing a stable interface to decrease Zn dendrites and H_(2)evolution during long-term cycling.When Na^(+) and ClO_(4)^(-) are introduced into an aqueous ZnSO_(4) electrolyte,a Zn/Zn symmetric cell shows durable and reversible Zn stripping/plating for 1500 h at a current density of 1 mA cm^(-2) and with an area capacity of 1 mAh cm^(-2).Zn/Na_(0.33)K_(0.1)V_(2)O_(5)·nH_(2)O full batteries exhibit a high capacity of 600 mAh g^(-1)at 0.1 A g^(-1) and long-term cycling performance for 5000 cycles,with a capacity of 200 mAh g^(-1) at 20 Ag^(-1).