Oxygen‑Deficient β‑MnO_(2)@Graphene Oxide Cathode for High‑Rate and Long‑Life Aqueous Zinc Ion Batteries

Recent years have witnessed a booming interest in grid-scale electrochemical energy storage,where much attention has been paid to the aqueous zinc ion batteries(AZIBs).Among various cathode materials for AZIBs,manganese oxides have risen to prominence due to their high energy density and low cost.However,sluggish reaction kinetics and poor cycling stability dictate against their practical application.Herein,we demonstrate the combined use of defect engineering and interfacial optimization that can simultaneously promote rate capability and cycling stability of MnO_(2) cathodes.β-MnO_(2) with abundant oxygen vacancies(VO)and graphene oxide(GO)wrapping is synthesized,in which VO in the bulk accelerate the charge/discharge kinetics while GO on the surfaces inhibits the Mn dissolution.This electrode shows a sustained reversible capacity of~129.6 mAh g^(−1) even after 2000 cycles at a current rate of 4C,outperforming the state-of-the-art MnO_(2)-based cathodes.The superior performance can be rationalized by the direct interaction between surface VO and the GO coating layer,as well as the regulation of structural evolution ofβ-MnO_(2) during cycling.The combinatorial design scheme in this work offers a practical pathway for obtaining high-rate and long-life cathodes for AZIBs.

欧洲千里光花发育相关基因SvGLOBOSA功能研究

菊科(Asteraceae)植物独特的头状花序具有重要的观赏与研究价值,其花发育分子机制复杂,目前相关报道较少。本研究对欧洲千里光(Senecio vulgaris)转录组数据进行筛选,初步得到MADS-box基因SvGLOBOSA(SvGLO),并对其功能进行了初步分析。通过生物信息学分析基因结构并预测其功能;qRT-PCR分析了SvGLO在野生型欧洲千里光不同组织中的相对表达量;在龙葵(Solanum nigrum)中过表达SvGLO并进行形态学观察;通过组织学染色分析转基因龙葵子房的组织细胞形态变化。结果表明,SvGLO的开放阅读框(open reading frame,ORF)长度为591 bp,编码196个氨基酸;具有典型的MADS-box和K-box结构域且在C末端含有PI基序(motif)EPFSFRVQPMQPNLQE,属于B类MADS-box基因的PI/GLO亚家族。qRT-PCR结果表明,SvGLO在花序组织中高表达,在营养器官中不表达;同时在过表达龙葵中观察萼片获得花瓣的部分特征,心皮转化为雄蕊状器官,果实发育异常。组织学染色分析结果表明,转基因龙葵的子房壁细胞形态和野生型雄蕊的花药壁细胞相似。以上结果表明,欧洲千里光SvGLO可能参与调控花瓣与雄蕊发育。

共掺杂策略协同激活阴离子氧化还原构建高容量钠离子电池层状氧化物阴极材料

作为锂离子电池的潜在替代品,钠离子电池由于成本、安全性等方面的优势吸引了广泛关注.但如何进一步提高其正极材料的能量密度仍是挑战,而通过激活阴离子氧化还原提供额外容量是一种可行的策略.本文报告了一种高性能锰基氧化物正极材料,Na_(0.67)Mg_(0.1)Zn_(0.1)Mn_(0.8)O_(2)(NMZMO).通过共掺杂策略协同激活阴离子氧化还原,此材料首圈可以放出~233 mAh g^(-1)的超高容量,明显高于Mg或Zn单掺杂的同类材料.综合多种光谱技术,作者证明了更高的容量源于更强的阴离子氧化还原活性.结合中子全散射以及共振非弹性X射线散射发现,Mg与Zn在高电压下会向面外迁移至四面体位点,诱导面内重排形成空位团簇,将氧阴离子以分子O_(2)的形式困于其中.Mg/Zn共存时,刺激了彼此更多的向面外迁移,为形成更多晶内分子O_(2)提供先决条件.本文提出了关于阴离子氧化还原的新见解,并为高容量钠电正极材料的开发提供了理论依据.

Supramolecular Surface Engineering of Carbon Dots Enables Matrix-Free Room Temperature Phosphorescence

Comprehensive Summary,Carbon dots(CDs)are an emerging class of nanomaterials with intriguing photophysical properties.Recently,achieving room temperature phosphorescence(RTP)for CDs has attracted considerable attention for biomedical and information applications.However,the CDs based RTP materials generally require the use of polymeric and inorganic matrix to provide the rigid environments,which remains a great challenge to obtain matrix-free CDs with RTP.Herein,a novel supramolecular strategy based on strong interparticle interactions has been developed to attain this objective,by covalent decoration of ureido-pyrimidinone(UPy,a multiple hydrogen bonding unit)on the surface of CDs.Structural characterizations validated the core-shell structure of the as-prepared CDs(EDTA-CDs)and demonstrated the successful attachment of UPy via post-modification(UPy-CDs).The presence of UPy recognition units render the strong hydrogen bonding between UPy-CDs,which stabilizes the triplet state via rigidifying effect.As a result,UPy-CDs exhibit matrix-free efficient RTP(λ_(em)=534 nm)with high brightness and long lifetime(33.6 ms)in the solid state.Owing to the dual-emission character,we further explored the application potential of UPy-CDs in information encryption and anti-counterfeiting.Overall,this work provides a new and facile strategy for achieving matrix-free phosphorescent CDs with elegant incorporation of supramolecular chemistry.

Strong interaction between phosphorus and wrinkle carbon sphere promote the performance of phosphorus anode material for lithium-ion batteries

The durable red phosphorus(RP)anode for lithium-ion batteries(LIBs)has attracted great attention owing to its high theoretical specific capacity(2596 mA·h·g^(-1))and moderate lithiation potential(~0.7 V vs.Li^(+)/Li).However,its intrinsic poor electrical conductivity,enormous volume expansion,and soluble intermediates(lithium polyphosphides,Li_(x)PP_(s))lead to poor cycling performance.To overcome these issues,we introduce a new type of wrinkle carbon spheres as the host for loading phosphorus through a vaporization-condensation strategy.Density functional theory calculations reveal that the wrinkle carbon sphere shows strong binding energy with P4 molecule,accelerating the adsorption and polymerization of P4,thus enhancing RP conversion in the preparation process.In the lithiation/delithiation process,the wrinkle carbon has strong bonding with phosphorus and strong adsorption with Li_(x)PP_(s),resulting in excellent cycling performance.The design strategy to modify RP polymerization via reforming the interaction between wrinkle carbon spheres and phosphorus expands the application of RP for LIBs and beyond.

A novel lysosome‐localized fluorescent probe with aggregation‐induced emission without alkalinizing effect

Herein,a novel small molecule probe,tetraphenylethylene‐cystein(TPE‐Cys),was rationally designed and developed for the intracellular lysosome localization.The combination of tetraphenylethylene and cysteine serve as a novel strategy for lysosome‐targeting,with significant aggregation‐induced emission increases with the proportion of water by as high as 25‐folds.Biofluorescence imaging experiments show that the probe TPE‐Cys has a good colocalization effect with the commercially available lysotracker red,with a Pearson correlation coefficient of 0.91.In addition,we also demonstrate that TPE‐Cys has good light stability.TPE‐Cys,as a neutral compound,is free of alkalinizing effect when applied in lysosome localization.Moreover,molecular dynamics simulations and density function theories are employed to explore the detailed aggregation process and the mechanism of TPE‐Cys aggregation in water solution.The mechanism of lysosome localization of probe TPE‐Cys was explained by cellular endocytosis process and the formation of larger particle in the more acidic environment of lysosomes.This work not only demonstrates an efficient strategy for the construction of fluorescent probes for lysosome localization,but also indicates that they are promising as live cell imaging tools.

Research progress on neutralizing epitopes and antibodies for the Rabies virus

Rabies is a zoonotic infectious disease with a high fatality rate.It is caused by a virus in the genus Lyssavirus and is a global public health threat.The rabies virus invades and infects cells mainly via a glycoprotein,which may involve multiple receptors.Neutralizing antibodies against the rabies virus function by blocking the binding of the glycoprotein to a receptor or preventing the membrane fusion process.Vaccination combined with anti-rabies virus neutralizing antibodies is essential for postexposure prophylaxis for category III exposure to the rabies virus.In this review,we discussed the neutralizing epitopes of the rabies virus and the neutralization mechanism of monoclonal antibodies.The neutralizing antibodies that have been commercialized or are under development are also summarized.Our review would provide a basis for the further development of safe and effective broadspectrum neutralizing antibodies to replace the rabies virus immunoglobulin in rabies post-exposure prophylaxis.