The etching strategy of zinc anode to enable high performance zinc-ion batteries

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

Amphipathic Janus Nanofibers Aerogel for Efficient Solar Steam Generation

Solar steam generation is a promising water purification technology due to its low-cost and environmentally friendly applications in water purification and desalination.However,hydrophilic or hydrophobic materials alone are insufficient in achieving necessary characteristics for constructing highquality solar steam generators with good comprehensive properties.Herein,novel hydrophile/hydrophobe amphipathic Janus nanofibers aerogel is designed and used as a host material for preparing solar steam generators.The product consists of an internal cubic aerogel and an external layer of photothermal materials.The internal aerogel is composed of electrospun amphipathic Janus nanofibers.Owing to the unique composition and structure,the prepared solar steam generator integrates the features of high water evaporation rate(2.944 kg m^(-2)h^(-1)under 1 kW m^(-2)irradiation),selffloating,salt-resisting,and fast performance recovery after flipping.Moreover,the product also exhibits excellent properties on desalination and removal of organic pollutants.Compared with traditional hydrophilic aerogel host material,the amphipathic Janus nanofibers aerogel brings much higher water evaporation rate and salt resistance.

Robustness analysis of control systems with disc uncertainties

For a class of control systems with disc uncertainties, robust performance anaysis is developed. On the strictly positive realness and H-infinity-norm of uncertain systems, from the geometric point of view, two new sufficient and necessary conditions are given. The largest H-infinity-norm bound, containing the coefficients of only stable polynomials and centered at a nominal stable point in the coecient space is found. The results obtained in the paper are tractable and concise, which is illustrated by some numerical examples.

Analysis on ISSR Markers of Some Waxberry Cultivars in Jiangsu Province

[Objective] This study aimed to investigate the genetic relationship among waxberry （Myrica rubra Bieb. et Zucc） cultivars in Jiangsu Province. [ Method] Eighteen waxberry cultivars （lines） in Jiangsu Province were analyzed using ISSR-PCR method, and molecular phylogenetic tree was constructed using UPGNA method. [ Result ~ A total of 70 DNA fragments were amplified with nine screened primers, including 43 polymorphic fragments, accounting for 61.4% of the total number of amplified fragments; 18 waxberry cultivars （lines） were clustered into 6 categories with the genetic distance of 0. 14, indicating that there is partial isolation on the basis of gene exchange between waxberry cultivars （lines） in Jiangsu Province. [ Conclusion] This study provided scientific basis for the protection and utilization of waxberry germplasm resources and cultivation of new varieties.

土著昆虫素毒蛾在本地植物芦苇与入侵植物互花米草上的生活史

互花米草(Spartina alterniflora)入侵盐沼生态系统导致了土著广食性昆虫素毒蛾(Laelia coenosa)发生宿主转移。但是,目前对素毒蛾在互花米草和芦苇(Phragmites australis)上的生活史规律的比较尚未见报道,而此信息对评价素毒蛾能否持续利用互花米草具有重要的参考价值。为了明确素毒蛾在其原始宿主芦苇和外来新宿主互花米草上的生活史动态,我们在上海崇明长江口盐沼湿地中,对素毒蛾在芦苇和互花米草生境中的发生情况进行了系统调查。结果显示,虽然素毒蛾在芦苇和互花米草上均一年发生3代,并都以幼虫越冬,但在互花米草生境中,越冬代幼虫开始越冬的时间要比芦苇中晚20d左右,其他世代中的多个虫态在互花米草上持续出现的时间也比芦苇上延迟了约10 d。这些结果表明,互花米草入侵后素毒蛾在外来植物上出现的持续时间虽然发生了延长,但其年世代数未变化。我们推测素毒蛾在互花米草和芦苇上生长发育规律的差异可能受生境的资源可利用性及两种植物的营养与防御水平调控。

Preparation and properties of temperature sensitive paint based on Eu(DBM)_3 phen as probe molecule

Probe molecule Eu(DBM)3 phen is made up of europium oxide(EuO),dibenzoylmethane(DBM) and1,10-phenanthroline(phen). The temperature sensitive paint(TSP) was compounded by the polymerization of the probe molecule, methyl methacrylate(MMA) and the initiator of benzoyl peroxide(BPO).The structure, morphology, luminescence property of probe molecule and the temperature quenching property of the temperature sensitive paint(TSP) were characterized by infrared spectrometer, UV-vis spectrometer, scanning electron microscopy and fluorescence spectrometer respectively. The infrared spectrum and UV-vis spectra show that Eu and DBM form six membered rings, and Eu-O coordinate bonds form. The nanocrystals are in sphere-like morphology with an average size of approximately100 nm. Fluorescence spectra present that the performance of temperature quenching is excellent,what’s more, TSP sample has different temperature sensitivity in various temperature scope. Particularly,under excitation of 286 nm, TSP has a highest temperature sensitivity between 50 and 60 ℃, and the strongest fluorescence emission reaches a peak(615 nm). It indicated that probe molecule(Eu(DBM)phen) has strong luminescent intensity and the temperature quenching properties of Eu(DBM)phen/PMMA is good.

Decorating rare-earth fluoride upconversion nanoparticles on AuNRs@Ag core-shell structure for NIR light-mediated photothermal therapy and bioimaging

Photothermal therapy(PTT)has presented its inherent application value in cancer treatment.Nevertheless,single-functional photothermal materials cannot meet the precise diagnosis and treatment of cance r.Therefo re,it is important to design a nanocomposite that has both high therapeutic efficiency and multimodal imaging capabilities.In our work,a new nanostructure of gold nanorods(AuNRs)with silver shells decorated by BaGdF5:Yb^(3+),Er^(3+)nanoparticle was synthesized by a simple way.The biostability of AuNRs is increased by coating with silver shells,and the AuNR@Ag nanoparticles can be used as excellent surface enhanced Raman scattering(SERS)probe.Moreover,the modification of BaGdF5:Yb^(3+),Er^(3+)nanoparticles provides the possibility of real-time optical imaging of the tumor area.Under the irradiation of NIR laser,the AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)nanocomposites(NCs)have strong upconversion emission and excellent photothermal conversion efficiency.Meanwhile,the NCs show low cytotoxicity and good biocompatibility in MTT cytotoxicity test.Moreover,the NCs are also exceptional contrast agents for CT imaging.For in vitro photothermal therapy test,NCs show excellent killing efficiency on tumor cells.Therefore,the multifaceted research of AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)multifunctional nanomaterials provides a break for high-efficiency tumor photothermal therapy and multimodal imaging.

Preparation and properties of Nd,Yb:GGG polycrystalline nanopowders

Gadolinium gallium garnet(GGG)polycrystalline powders doped with Nd,Yb were prepared by co-precipitation method.The structure,phase and properties of powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS)and fluorescence spectroscopy.XRD analysis indicated that the crystallization of Nd,Yb:GGG powders occur at 900􀄇.SEM analysis showed that the morphology of the powders was irregular and the average radius is 68.74 nm.FTIR analysis manifested that pure Nd,Yb:GGG powders were formed at 900􀄇.The fluorescence spectrum revealed that the most strong emission of Nd,Yb:GGG powders was 1030 nm,which was attributed to 2F5/2􀄺2F7/2 of Yb3+.The possible formation mechanism of Nd,Yb:GGG powders were preliminarily discussed.

基于Coq的第三代微积分机器证明系统

本文基于证明辅助工具Coq,完整实现林群院士和张景中院士等倡导的第三代微积分|没有极限的微积分|理论构架的形式化验证,包括对张景中等发表的题为\微积分基础的新视角"论文中全部定义和定理的Coq描述.进而,对定理无例外地给出Coq的机器证明代码,所有形式化过程已被Coq验证,并在计算机上运行通过,体现了基于Coq的数学定理机器证明具有可读性和交互性的特点,其证明过程规范、严谨、可靠.本文是实践研究人员利用计算机学习、理解、构建乃至教育现代数学理论的一个尝试.

A necessary and sufficient condition on robust SPR stabilizability for low degree systems

For low degree systems (n≤3), it is verified that all convex combination of a (s) and b(s) keeping Hurwitzness is a necessary and sufficient condition for the existence of c(s) such that both c(s)/a(s) and c(s)/b(s) are SPR.

The piRNA pathway is required for nucleopolyhedrovirus replication in Lepidoptera

The Piwi-interacting RNA(piRNA)pathway has been shown to be involved in the antiviral defense against RNA viruses,especially in mosquitoes,but its universality has been questioned.Here,we used the Bombyx mori nucleopolyhedrovirus(BmNPV)-infected silkworm as a model to explore the effects of the key factors of piRNA pathway,BmAgo3 and Siwi,on replication of a large DNA virus(belonging to the family of Baculoviridae).We demonstrated that BmAgo3 and Siwi could promote the replication of BmNPV through both overexpression and knockdown experiments in BmN cell lines and silkworm larvae.In addition,we also studied the effect of PIWI-class genes on Autographa californica nucleopolyhedrovirus(AcMNPV)replication in the Spodoptera frugiperda cell line Sf9.By knocking down the expression of PIWI-class genes in Sf9,we found that Piwi-like-1 and Piwi-like-2-3 could inhibit AcMNPV replication,while Piwi-like-4-5 promoted virus replication.Our study provides compelling evidence that the piRNA pathway affects host infection by exogenous viruses in Lepidoptera.Also,our results reflect the diversity of the roles of PIWI-class genes in virus infection of the host across species.This study is the first to explore the interaction of PIWI-class proteins with DNA viruses,providing new insights into the functional roles of the piRNA pathway.

Eu^(3+)ions grafted polyacrylonitrile nanofibers possessing enhanced fluorescence performance by introducing benzoic acid as assistant ligand

Eu^(3+) ions were grafted onto the surface of electrospun polyacrylonitrile(PAN)nanofibers through coordination effect between C≡N groups on PAN nanofibers and Eu^(3+) ions,and benzoic acid(BA)was introduced as an assistant ligand.The impacts of concentrations of Eu^(3+) ions and BA,and reaction time on the properties of final products were investigated.The results reveal that Eu^(3+) ions can be successfully grafted onto PAN nanofibers,but the fluorescence intensity of the obtained PAN@Eu^(3+) nanofibers is very weak.After BA is introduced as the assistant ligand,the fluorescence intensity of the obtained PAN@(Eu^(3+)/BA)nanofibers is greatly stronger than that of PAN@Eu^(3+)nanofibers,and meanwhile,concentration quenching effect of Eu^(3+) ions can be effectively restrained.Furthermore,the superior structure of PAN@(Eu^(3+)/BA)nanofibers not only brings the effective utilization of precious elemental europium,but also guarantees high mechanical strength.