Earth-abundant CuFeS_(2) nanocrystals@graphite felt electrode for high performance aqueous polysulfide/iodide redox flow batteries

Due to their high energy density and low price,aqueous polysulfide/iodide redox flow batteries are appealing for scalable energy storage.However,the greatest barrier to their practical uses is the low electrochemical kinetics of the redox reactions of polysulfide ions on graphite electrodes,which often limit their energy efficiency and power density.In this study,the CuFeS_(2)nanomaterial was successfully synthesized through the hot injection method,and CuFeS_(2)nanomaterials were uniformly coated onto the surfaces and sandwiched into graphite felt(GF);this process can significantly boost the electrocatalytic activities of S^(2-)/S^(2-)_(x)redox reactions by improving the charge transfer process,which has been proven by the electrochemical measurement and density functional theory(DFT)simulations.The polysulfide-iodide flow battery,with GF-CuFeS_(2)serving as the negative electrode,can achieve a high energy efficiency of 79.6%at 20 mA/cm^(2),a power density of 50.7 mW/cm^(2),and a stable energy efficiency retention of 87.0%after 180 cycles.

A Liquid Metal Reaction System for Advanced Material Manufacturing

CONSPECTUS:Liquid metal exhibits the unique advantages of both the liquid and metal,including excellent deformability,high thermal conductivity,and electrical conductivity.The exploration of liquid metal is a new opportunity and revolution for the application of metal materials,including the flexible devices,catalysis,microfluidic,and drug delivery.In addition to the above applications,the characteristics of excellent inclusive ability with the majority of the elements and abundant vacancies in the bulk make it a new type of reaction medium different from traditional aqueous and organic solutions,exhibiting great potential in the precise construction of materials.To date,the research of using liquid metal as a reaction system to synthesize materials is still in its infancy.When acting as a reaction system,the vacancies inside and the smooth layering surfaces without grain boundaries allow liquid metals to encapsulate heterogeneous atoms,confine the precursors in atomically thick layers and realize the self-limiting growth of 2D material.Besides,the good rheological property makes it possible to construct 2D arrays on its surface.Except for the properties mentioned above,as a kind of metal,its excellent electrical conductivity and ductility provide a new idea for the preparation of composite materials in the energy field.Indeed,liquid metals provide attractive prospects in manufacturing advanced materials including 2D materials and functional composite materials.Thus,this Account aims to focus on the controllable fabrication of 2D materials and functional composite materials by liquid metals.Based on the characteristics of the surface layering and solidification and of excellent fluidity,the self-limited growth and ordered arrangement of 2D materials on liquid metal surfaces can be achieved,which enriches the material structures and leads to new properties.By constructing an in situ synthesis and observation system,the growth and assembly behavior of 2D materials on the liquid metal can be observed directly.Combining the electrical property,deformability,ductility,and high inclusive ability with other materials,the liquid metal reaction system can also realize the preparation of new functional composite materials toward various applications,such as the energy field.Except for the 2D materials and functional composite materials mentioned here,liquid metals also provide more possibilities for fabricating other promising materials,like wafer-scale semiconductors,magic-angle graphene,flexible functional materials,biomedical materials,and so on.The research concerning the manufacturing of advanced materials on liquid metals is still in its infancy.We believe that the development of related technologies offering in-depth investigation and theoretical understanding on liquid metals will lay a solid foundation for the basic research and practical application of more advanced materials.

Pt_(1)/Ni_(6)Co_(1)layered double hydroxides/N-doped graphene for electrochemical non-enzymatic glucose sensing by synergistic enhancement of single atoms and doping

The development of novel single-atom catalysts is important for highly efficient electrochemical catalysis and sensing.In this work,a novel Pt single atoms(SAs)supported on Ni_(6)Co_(1)layered double hydroxides/nitrogen-doped graphene(Pt_(1)/Ni_(6)Co_(1)LDHs/NG)was constructed for electrochemical enzyme-free catalysis and sensing towards glucose.The loading of Pt single atoms increases with doping of Co atoms that generate more anchoring sites for Pt SAs.The resulting Pt_(1)/Ni_(6)Co_(1)LDHs/NG exhibits low oxidative potential of 0.440 V with high sensitivity of 273.78μA·mM^(−1)·cm^(−2)toward glucose,which are 85 mV lower and 15 times higher than those of Ni(OH)_(2),respectively.Pt_(1)/Ni_(6)Co_(1)LDHs/NG also shows excellent selectivity and great stability during 5-week testing.Theoretical and experimental results show that the boosted performance of Pt_(1)/Ni_(6)Co_(1)LDHs/NG originates from its stronger binding energy with glucose and the synergistic effect of Pt SAs,Co doping,and NG.This work provides a general strategy of designing highly active SACs for extending their application in electrochemical sensing.

RNAirport:a deep neural network-based database characterizing representative gene models inplants

A 5'-leader,known initially as the 5'-untranslated region,contains multiple isoforms due to alternative splicing(aS)and alternative transcription start site(aTSS).Therefore,a representative 5'-leader is demanded to examine the embedded RNA regulatory elements in controlling translation efficiency.Here,we develop a ranking algorithm and a deep-learning model to annotate representative 5'-leaders for five plant species.We rank the intra-sample and inter-sample frequency of aS-mediated transcript isoforms using the Kruskal-Wallis test-based algorithm and identify the representative aS-5'-leader.To further assign a representative 5'-end,we train the deep-learning model 5'leaderP to learn aTsS-mediated 5'-end distribution patterns from cap-analysis gene expression data.The model accurately predicts the 5'-end,confirmed experimentally in Arabidopsis and rice.The representative 5'-leader-contained gene models and 5'leaderP can be accessed at RNAirport(http:/www.rnairport.com/leader5P/).The Stage 1 annotation of 5'-leader records 5'-leader diversity and will pave the way to Ribo-Seq open-reading frame annotation,identical to the project recently initiated by human GENCODE.

Translation machinery: the basis of translational control

Messenger RNA(mRNA)translation consists of initiation,elongation,termination,and ribosome recycling,carried out by the translation machinery,primarily including tRNAs,ribosomes,and translation factors(TrFs).Translational regulators transduce signals of growth and development,as well as biotic and abiotic stresses,to the translation machinery,where global or selective translational control occurs to modulate mRNA translation efficiency(TrE).As the basis of translational control,the translation machinery directly determines the quality and quantity of newly synthesized peptides and,ultimately,the cellular adaption.Thus,regulating the availability of diverse machinery components is reviewed as the central strategy of translational control.We provide classical signaling pathways(e.g.,integrated stress responses)and cellular behaviors(e.g.,liquideliquid phase separation)to exemplify this strategy within different physiological contexts,particularly during hostemicrobe interactions.With new technologies developed,further understanding this strategy will speed up translational medicine and translational agriculture.

Engineering disease-resistant plants with alternative translation efficiency by switching uORF types through CRISPR

Engineering disease-resistant plants can be a powerful solution to the issue of food security.However,it requires addressing two fundamental questions:what genes to express and how to control their expressions.To find a solution,we screen CRISPR-edited upstream open reading frame(uORF)variants in rice,aiming to optimize translational control of disease-related genes.By switching uORF types of the 5′-leader from Arabidopsis TBF1,we modulate the ribosome accessibility to the downstream firefly luciferase.We assume that by switching uORF types using CRISPR,we could generate uORF variants with alternative translation efficiency(CRISPR-aTrE-uORF).These variants,capable of boosting translation for resistance-associated genes and dampening it for susceptible ones,can help pinpoint previously unidentified genes with optimal expression levels.To test the assumption,we screened edited uORF variants and found that enhanced translational suppression of the plastic glutamine synthetase 2 can provide broad-spectrum disease resistance in rice with minimal fitness costs.This strategy,which involves modifying uORFs from none to some,or from some to none or different ones,demonstrates how translational agriculture can speed up the development of disease-resistant crops.This is vital for tackling the food security challenges we face due to growing populations and changing climates.

General radical difluoromethylation using difluoroacetic anhydride via photoredox catalysis

CF_(2)H-containing molecules play pivotal roles in diverse fields from medicinal chemistry to materials science. However, the application of existing CF_(2)H reagents as a source of CF_(2)H radical is limited by their reactivity and preparation. Herein, we develop a simple and general visible-light-catalyzed radical difluoromethylation reaction of alkenes, dienes, and heteroaromatics using commercially available, easy-to-handle, and low-cost difluoroacetic anhydride as the CF_(2)H reagent. This scalable protocol enables the convenient synthesis of a range of CF_(2)H-containing compounds under mild conditions, exhibiting a broad substrate scope and functional group tolerance. Potential applications are further demonstrated by gram-scale synthesis, sunlight experiments, derivatization experiments as well as the synthesis of bioactive molecules.

Electrochemical Oxidative Csp^3—H/S—H Cross-Coupling with Hydrogen Evolution for Synthesis of Tetrasubstituted Olefins

Tetrasubstituted olefins are significant scaffolds as they are prevalent in many biologically active compounds and versatile building blocks for organic synthesis. Herein, we report an electrochemical oxidative Csp^3—H/S—H cross-coupling reaction, in which various tetrasubstituted olefins were prepared under base-free, transition metal-free, and oxidants-free reaction conditions.

Oxidation-Induced C--H Functionalization： A Formal Way for C--H Activation

Cross-coupling reactions have developed widely and provided a powerful means to synthesize a variety of compounds in each chemical field. The compounds which have C--H bonds are widespread in fossil fuels, chemical raw materials, biologically active molecules, etc. Using these readily- available substances as substrates is high atom- and step-economy for cross-coupling reactions. Over the past decades, our research group focused on finding and developing new strategies for C--H functionalization. Compared with classical C--H activation methods, for example, C--H bonds are depro- tonated by strong base or converted into C--M bonds, oxidation-induced C--H functionalization would be another pathway for C--H bond activation. This perspective shows a brief introduction of our recent works in this oxidation-induced C--H functionalization. We categorized this approach of these C--H bond activations by the key intermediates, radical cations, radicals and cations.

Structural Designs for Accommodating Volume Expansion in Sodium Ion Batteries

T At the forefront of energy storage field, developing sodium ion batteries （SIBs） has drew a wide concern due to relatively low cost and abundant resource, comparing with lithium ion batteries （LIBs）. Serious volume expansion constraints the electrochemical performance of the conver- sion/alloying materials, despite of their high reversible capacities or theoretical capacities. Here, from the perspective of structural designs, we systemat- ically study four types of routes to accommodate volume expansion. Delicate and peculiar nanostructures based on nanocrystallization engineering are widely focused on, covering nanosheet assembly and nanoarray construction. Robust materials such as carbon-based materials can be utilized as the buffer matrix, mitigating the mechanical stress during the charge/discharge process. Besides, recent studies have demonstrated void space reservation in nanostructures was also beneficial for adapting to volume changes. Moreover, for conversion materials, numerous works have confirmed the advanta- geous influence of interlayer spacing regulation. We also explained the superiority and challenges for further giving scope to structural designs. Sketching out the future studies in SIBs, in situ characterizations are supposed to be highlighted, as well as in-depth researches on the stress evolution caused by volume expansion.

Tuning radical reactivity for selective radical/radical cross-coupling

Radical/radical cross-coupling represents a straightforward way for the construction of new chemical bonds in theory and has received more and more attention over the past several years. Until now, it is challenging to achieve the selective bond formation between two transient radicals since selective radical cross-coupling usually happens between persistent radical and transient radical. However, the number of persistent radicals is much less than that of transient radicals. These issues limit the application of radical/radical cross-coupling in the construction of new chemical bonds. To solve this, we proposed a novel strategy ‘‘tuning radical reactivity" that could tune transient radical into persistent radical. This paper will introduce the concept and recent developments of ‘‘tuning radical reactivity".

Precise electro-reduction of alkyl halides for radical defluorinative alkylation

Reported here is a precise electro-reduction strategy for radical defluorinative alkylation towards the synthesis of gem-difluoroalkenes from α-trifluoromethylstyrenes. According to the redox-potential difference of the radical precursors, direct or indirect electrolysis is respectively adopted to realize the precise reduction. An easy-to-handle, catalyst-and metal-free condition is developed for the reduction of alkyl radical precursors that are generally easier to be reduced than α-trifluoromethylstyrenes,while a novel electro-Ni-catalytic system is established for the electro-reduction of alkyl bromides or chlorides towards the electrochemical synthesis of gem-difluoroalkenes. The merit of this protocol is exhibited by its mild conditions, wide substrate scope, and scalable preparation. Mechanistic studies and DFT calculations proved that the coordination of α-trifluoromethylstyrenes to Ni-catalyst prevents the direct reduction of the alkene and, in turn, promotes the activation of alkyl bromide through halogen atom transfer mechanism.

An Electrochemical Synthesis Approach for Tetrasubstituted Olefins

Since tetrasubstituted olefins serve as the key structure motifs in a large number of biologically active compounds,methods for synthesis of tetrasubstituted olefins are highly desirable.Among various synthetic methodologies,the most known strategies are the functionalization of olefins,alkynes,and allenes.For example,Zhang,Gosselin and co-workers prepared a series of tetrasubstituted olefins via Suzuki-Miyaura coupling (Scheme 1a).[1] Morandi and co-workers reported a palladium-catalyzed intermolecular aryliodination of internal alkynes (Scheme 1b).[2] Ma and co-workers prepared a series of tetrasubstituted olefins by using readily available organozinc reagents and 2,3-allenals (Scheme 1c).[3] Despite extensive advances,the reported methods often require pre-prepared starting materials,inevitably leading to some by-products.Recently,under the supervision of Prof.Wang and Lei,we and Yang et al.reported an unprecedented electrochemical oxidative Csp3-H/S-H cross-coupling reaction between thiophenols and acetonitrile (Scheme 1d),yielding a series of tetrasubstituted olefins under exogenous-oxidant-free conditions.

Oxidative cross-coupling: an alternative way for C–C bond formations

Coupling reaction usually refers to the direct C–C bond formation between two carbon fragments.Generally, cross-coupling reactions between nucleophiles and electrophiles have been extensively studied and become the classic model for bond constructions. Another reaction model, bond formation from two nucleophiles through oxidative cross-coupling, has received more and more attention over the past few years. This paper will discuss the concept of oxidative cross-coupling and give an overview of its recent development.

New designing for nanostructured 2D materials and 2D superlattices

As the most remarkable candidate for the next-generationelectronics, two-dimensional （2D） materials have at-tracted much interest. Recently in a letter in NatureMaterials, Professor David A. Muller and Lain-Jong Liand their cooperators reported the direct synthesis ofone-dimensional （1D） MoS2 channels embedded in 2DWSe2 monolayers through a dislocation-catalyzed strategy[1].

Touch Ablation of Lithium Dendrites via Liquid Metal for High-Rate and Long-Lived Batteries

High energy density lithium(Li)metal batteries have attracted great attention,but they are faced with challenges of cycling instability and safety hazards.Due to high activity and drastic volume changes of metallic Li,potential dendritic risks cannot be fully eliminated.Therefore,suppressing already existing Li dendrites must be evaluated.In addition,Li-active solids alloying with Li always face mechanical instability and fractures with cycling.Herein,we present touch ablation of dendrites by liquid metal,namely forming a defense layer on the electrode to directly react with the dendrites.Embrittlement,supercooling,and other liquid characteristics make the liquid gallium(Ga)exhibit continuous and reversible reactions with Li.The unique layout with a hierarchical porous structure inhibits upward growth of the dendrites.The protected Li||Li cells achieve stable cyclic performance even at 10 mA cm^(–2)and a large capacity of 5 mA h cm^(-2).

Dual Effects of Interfacial Interaction and Geometric Constraints on Structural Formation of Poly(butylene terephthalate)Nanorods

When the size of the material is smaller than the size of the molecular chain,new nanostructures can be formed by crystallizing polymers in nanoporous alumina.However,the effect of pore wall and geometric constraints on polymer nanostructures remains unclear.In this study,we demonstrate three new restricted nanostructures{upright-,flat-and tilting-ring}in polybutylene terephthalate(PBT)nanorods prepared from nanoporous alumina.The dual effects of geometrical constraints and interfacial interactions on the formation of PBT nanostructures were investigated for the first time by using X-ray diffraction and Cerius^(2) modeling packages.Under weak constraints,the interaction between pore wall and the PBT rings is dominant and the ring plane tends to be parallel to the pore wall and radiate outward to grow the upright-ring crystals.Surprisingly,in strong 2D confinement,a structural formation reversal occurs and geometrical constraints overpower the effect of pore wall.Rings tend to pile up vertically or obliquely along the long axis of the rod,so the flat-and tilting-ring crystals are predominate in the constrained system.In principle,our study of the nanostructure formation based on the geometrical constraints and the pore wall interfacial effects could provide a new route to manipulate the chain assembly at the nanoscale,further improving the performance of polymer nanomaterial.

Radical–Radical Cross-Coupling Assisted N–S Bond Formation Using Alternating Current Protocol

Alternating current(AC)electrolysis is a promising,yet challenging,and under-developed protocol in organic synthesis.To achieve as high an atomefficiency as possible and avoid the use of external oxidant,electrochemistry has become a standard organic synthesis tool.Herein,an AC-basedprotocol is a superior option than its counterpart,direct current(DC),especially for those reactions that cannot be accomplished by DC.

Regioselective electrochemical radical cascade cyclization of internal alkynes to selenated and trifluoromethylated dihydropyran

Dihydropyran(DHP)compounds are not only found in natural products and bioactive molecules,but also serve as important precursors in organic synthesis.Nonetheless,traditional methods for the construction of such compounds are usually limited to disubstituted DHPs.To address this synthetic challenge,reported here is an efficient electrochemical strategy toward the selenated and trifluoromethylated DHP compounds.The reaction proceeded smoothly under mild electrolysis conditions.The broad substrate scope(>50 examples)and scalable synthesis demonstrated the complexity-building potential of the strategy.Initial mechanistic studies reveal that cyclization may involve a radical process.This protocol may promote the further development of diversified synthesis of multi-substituted dihydropyran.

HPY1协同促进水稻源库平衡提高产量水平

水稻产量在生理上是由光合作用能力(源)和籽粒大小/数量(库)共同决定的.同时提升源和库将有助于水稻产量的进一步提升.因此,发掘协同促进源库的有利基因将有助于在分子水平上解析水稻源库相互协调的作用机制,从而促进水稻高产改良.本研究发现HPY1是一个由转座子衍生而来的转录因子编码基因,其高度保守,在水稻种质资源中均无任何突变.本文通过辐射诱变得到了1个HPY1的功能获得型突变等位基因,其通过协同促进Rubisco活性和籽粒大小从而提高水稻产量.HPY1通过直接结合Rubisco小亚基编码基因RbcS2、RbcS3和RbcS4,以及调控籽粒大小基因CCP1、FLO2,上调其转录,从而提高水稻光合速率、生物量、种子大小和籽粒产量.该发现不仅有助于从分子水平深入理解水稻源库协调的作用机制,同时也提供了一种水稻高产改良的有效策略.