Understanding AIE and ACQ phenomenon of organometallic iridium(Ⅲ) complexes by simple cationization engineering

Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborately designed and synthesized a pair of mononuclear iridium(Ⅲ) complexes with similar structures but different degrees of cationization. [Ir2-f][2PF_(6)] with two counterions is obtained by simple Nmethylation of the ancillary ligand of [Ir1-f][PF_(6)] which is a classic cationic iridium(Ⅲ) complex. Such a tiny modification results in tremendously different optical properties in dilute solutions and powders.[Ir1-f][PF_(6)] exhibits weak light in solution but enhanced emission in solid-state as well as poly(methyl methacrylate) matrix, indicative of its aggregation-induced emission(AIE) activity. On the sharp contrary, [Ir2-f][2PF_(6)] is an aggregation-caused quenching(ACQ) emitter showing strong emission in the isolated state but nearly nonemissive in aggregation states. Benefiting from the appealing characteristics of mechanochromic luminescence and AIE behavior, [Ir1-f][PF_(6)] has been successfully applied in reversible re-writable data recording and cell imaging. These results might provide deep insights into AIE and ACQ phenomenon of iridium(Ⅲ) complexes and facilitate the development of phosphorescent materials with promising properties.

Molecular dynamics simulations on the interactions between nucleic acids and a phospholipid bilayer

Recently,lipid nanoparticles(LNPs)have been extensively investigated as non-viral carriers of nucleic acid vaccines due to their high transport efficiency,safety,and straightforward production and scalability.However,the molecular mechanism underlying the interactions between nucleic acids and phospholipid bilayers within LNPs remains elusive.In this study,we employed the all-atom molecular dynamics simulation to investigate the interactions between single-stranded nucleic acids and a phospholipid bilayer.Our findings revealed that hydrophilic bases,specifically G in single-stranded RNA(ssRNA)and single-stranded DNA(ssDNA),displayed a higher propensity to form hydrogen bonds with phospholipid head groups.Notably,ssRNA exhibited stronger binding energy than ssDNA.Furthermore,divalent ions,particularly Ca2+,facilitated the binding of ssRNA to phospholipids due to their higher binding energy and lower dissociation rate from phospholipids.Overall,our study provides valuable insights into the molecular mechanisms underlying nucleic acidphospholipid interactions,with potential implications for the nucleic acids in biotherapies,particularly in the context of lipid carriers.

Fabrication and Properties of a New Reactive Diluent for Cationic UV Curing

The reactive diluent prepared by siloxane modified Trimethylene oxide can improve the performance of the UV curing system.Therefore,1,7-bis[(3-ethyl-3-methoxyoxacylobutane)propyl]octadecylosiloxane(BEMOPOMTS)was synthesized from diethyl carbonate,trimethylopropanes,allyl bromide,and 1,1,3,3,5,5,7,7-octadecylosiloxane as the main raw materials.BEMOPOMTS can be used as reactive diluents in the field of cationic UV curing.It has good thermal stability,and the addition of BEMOPOMTS significantly improves the tensile strength and elongation at break of epoxy resin.Compared with the pure epoxy resin,adding 20%BEMOPOMTS increased the elastic modulus by 25%to 677 MPa.

Exploring the Cation Regulation Mechanism for Interfacial Water Involved in the Hydrogen Evolution Reaction by In Situ Raman Spectroscopy

Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.Unfortunately,investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment.Here,the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry,in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques.Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction.When comparing the different cation electrolyte systems at a given potential,the frequency of the interfacial water peak increases in the specified order:Li+<Na^(+)<K^(+)<Ca^(2+)<Sr^(2+).The structure of interfacial water was optimized by adjusting the radius,valence,and concentration of cation to form the two-H down structure.This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance.Therefore,local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure.

Cationic ordering transition in oxygen-redox layered oxide cathodes

Understanding the structural origin of the competition between oxygen 2p and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density Li/Na-ion cathodes.Here,we reveal the correlation between cationic ordering transition and OR degradation in ribbon-ordered P3-Na_(0.6)Li_(0.2)Mn_(0.8)O_(2) via in situ structural analysis.Comparing two different voltage windows,the OR capacity can be improved approximately twofold when suppressing the in-plane cationic ordering transition.We find that the intralayer cationic migration is promoted by electrochemical reduction from Mn^(4+)to Jahn–Teller Mn^(3+)and the concomitant NaO_(6) stacking transformation from triangular prisms to octahedra,resulting in the loss of ribbon ordering and electrochemical decay.First-principles calculations reveal that Mn^(4+)/Mn^(3+)charge ordering and alignment of the degenerate eg orbital induce lattice-level collective Jahn–Teller distortion,which favors intralayer Mn-ion migration and thereby accelerates OR degradation.These findings unravel the relationship between in-plane cationic ordering and OR reversibility and highlight the importance of superstructure protection for the rational design of reversible OR-active layered oxide cathodes.

Enabling an Inorganic-Rich Interface via Cationic Surfactant for High-Performance Lithium Metal Batteries

An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium bromide(CTAB),a cationic surfactant,is adopted to draw more anions into EDL by ionic interactions that shield the repelling force on anions during lithium plating.In situ electrochemical surface-enhanced Raman spectroscopy results combined with molecular dynamics simulations validate the enrichment of NO_(3)^(−)/FSI−anions in the EDL region due to the positively charged CTA^(+).In-depth analysis of SEI structure by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results confirmed the formation of the inorganic-rich SEI,which helps improve the kinetics of Li^(+)transfer,lower the charge transfer activation energy,and homogenize Li deposition.As a result,the Li||Li symmetric cell in the designed electrolyte displays a prolongated cycling time from 500 to 1300 h compared to that in the blank electrolyte at 0.5 mA cm^(-2) with a capacity of 1 mAh cm^(-2).Moreover,Li||LiFePO_(4) and Li||LiCoO_(2) with a high cathode mass loading of>10 mg cm^(-2) can be stably cycled over 180 cycles.

Structurally Flexible 2D Spacer for Suppressing the Electron-Phonon Coupling Induced Non-Radiative Decay in Perovskite Solar Cells

This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PSCs).Via A-site cation engineering,a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine(CMA^(+))cation,which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations,compared to the rigid phenethyl methylamine(PEA^(+))analog.It demonstrates a significantly lower non-radiative recombination rate,even though the two types of bulky cations have similar chemical passivation effects on perovskite,which might be explained by the suppressed carrier capture process and improved lattice geometry relaxation.The resulting PSCs achieve an exceptional power conversion efficiency(PCE)of 25.5%with a record-high opencircuit voltage(V_(OC))of 1.20 V for narrow bandgap perovskite(FAPbI_(3)).The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PSCs approaching the Shockley-Queisser limit.

Modulating charge separation and transfer for high-performance photoelectrodes via built-in electric field

Constructing a built-in electric field has emerged as a key strategy for enhancing charge separation and transfer,thereby improving photoelectrochemical performance.Recently,considerable efforts have been devoted to this endeavor.This review systematically summarizes the impact of built-in electric fields on enhancing charge separation and transfer mechanisms,focusing on the modulation of built-in electric fields in terms of depth and orderliness.First,mechanisms and tuning strategies for built-in electric fields are explored.Then,the state-of-the-art works regarding built-in electric fields for modulating charge separation and transfer are summarized and categorized according to surface and interface depth.Finally,current strategies for constructing bulk built-in electric fields in photoelectrodes are explored,and insights into future developments for enhancing charge separation and transfer in high-performance photoelectrochemical applications are provided.

Genome-Wide Exploration of the Grape GLR Gene Family and Differential Responses of VvGLR3.1 and VvGLR3.2 to Low Temperature and Salt Stress

Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR)family,comprising highly conserved ligand-gated ion channels,regulates plant growth and development in response to stress.In this study,11 members of the VvGLR gene family in grapes were identified using whole-genome sequence analysis.Bioinformatic methods were employed to analyze the basic physical and chemical properties,phylogenetic trees,conserved domains,motifs,expression patterns,and evolutionary relationships.Phylogenetic and collinear analyses revealed that the VvGLRs were divided into three subgroups,showing the high conservation of the grape GLR family.These members exhibited 2 glutamate receptor binding regions(GABAb and GluR)and 3-4 transmembrane regions(M1,M2,M3,and M4).Real-time quantitative PCR analysis demonstrated the sensitivity of all VvGLRs to low temperature and salt stress.Subsequent localization studies in Nicotiana tabacum verified that VvGLR3.1 and VvGLR3.2 proteins were located on the cell membrane and cell nucleus.Additionally,yeast transformation experiments confirmed the functionality of VvGLR3.1 and VvGLR3.2 in response to low temperature and salt stress.Thesefindings highlight the significant role of the GLR family,a highly conserved group of ion channels,in enhancing grape stress resistance.This study offers new insights into the grape GLR gene family,providing fundamental knowledge for further functional analysis and breeding of stress-resistant grapevines.

A Modified Principal Component Analysis Method for Honeycomb Sandwich Panel Debonding Recognition Based on Distributed Optical Fiber Sensing Signals

The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scattering have been extensively deployed in structural health monitoring due to their advantages,such as lightweight and ease of embedding.However,identifying the precise location of damage from the optical fiber signals remains a critical challenge.In this paper,a novel approach which namely Modified Sliding Window Principal Component Analysis(MSWPCA)was proposed to facilitate automatic damage identification and localization via distributed optical fiber sensors.The proposed method is able to extract signal characteristics interfered by measurement noise to improve the accuracy of damage detection.Specifically,we applied the MSWPCA method to monitor and analyze the debonding propagation process in honeycomb sandwich panel structures.Our findings demonstrate that the training model exhibits high precision in detecting the location and size of honeycomb debonding,thereby facilitating reliable and efficient online assessment of the structural health state.

Surface Water Processes in Coping with Anthropogenic Impact in a Coastal Eastern Mediterranean Region

Rivers are progressively being exposed to increased anthropogenic pollution stresses that are undermining their designated uses and affecting sensitive coastal areas. In this study, three adjacent eastern Mediterranean coastal rivers, Ibrahim, Kaleb and Beirut, were evaluated. Water quality samples were collected in dry and wet seasons from different sampling sites along the river from the source to the outlet which represent a gradient of increased urbanization. The spatiotemporal variability of the physio-chemical properties, heavy metals (Zn, Pb, Cu, Cr, and Cd) and organic matter (DOC) were statistically analyzed to better understand the contribution of point and nonpoint pollution sources. The three rivers (Beirut, Kaleb and Ibrahim) show a similar behavior in calcium and carbonate alkalinity due to the carbonate mineral weathering effect, so they are of calcium bicarbonate type due to their calcareous geological nature. The speciation of anions was affected by temporal variation. Moreover, it is obvious that the Beirut River has a different behavioral characteristic where the water is a sulfate type water with a preferable metal-OM complexation mainly with lead, zinc and copper, whereas Kaleb and Ibrahim are considered to be of a nitrate phosphate type with a preferable metal inorganic complexation, especially copper, that has a consistent behavior in both types of waters. This difference is attributed to the urbanization effect highly impacting the Beirut River.

Trace Amounts of Triple-Functional Additives Enable Reversible Aqueous Zinc-Ion Batteries from a Comprehensive Perspective

Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on the anode.Despite numerous strategies to alleviate these side reactions have been demonstrated,they can only provide limited performance improvement from a single aspect.Herein,a triple-functional additive with trace amounts,ammonium hydroxide,was demonstrated to comprehensively protect zinc anodes.The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes.Moreover,cationic NH^(4+)can preferentially adsorb on the Zn anode surface to shield the“tip effect”and homogenize the electric field.Benefitting from this comprehensive protection,dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized.Besides,improved electrochemical performances can also be achieved in Zn//MnO_(2)full cells by taking the advantages of this triple-functional additive.This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective.

A novel cationic collector for silicon removal from collophane using reverse flotation under acidic conditions

We analyzed a novel cationic collector using chemical plant byproducts,such as cetyltrimethylammonium bromide(CTAB)and dibutyl phthalate(DBP).Our aim is to establish a highly effective and economical process for the removal of quartz from collophane.A microflotation test with a 25 mg·L^(−1)collector at pH value of 6-10 demonstrates a considerable difference in the floatability of pure quartz and fluorapatite.Flotation tests for a collophane sample subjected to the first reverse flotation for magnesium removal demonstrates that a rough flotation process(using a 0.4 kg·t−1 new collector at pH=6)results in a collophane concentrate with 29.33wt%P_(2)O_(5)grade and 12.66wt%SiO2 at a 79.69wt%P_(2)O_(5)recovery,providing desirable results.Mechanism studies using Fourier transform infrared spectroscopy,zeta potential,and contact angle measurements show that the adsorption capacity of the new collector for quartz is higher than that for fluorapatite.The synergistic effect of DBP increases the difference in hydrophobicity between quartz and fluorapatite.The maximum defoaming rate of the novel cationic collector reaches 142.8 mL·min−1.This is considerably higher than that of a conventional cationic collector.

Etching‑Induced Surface Reconstruction of NiMoO_(4) for Oxygen Evolution Reaction

Rational reconstruction of oxygen evolution reaction(OER)precatalysts and performance index of OER catalysts are crucial but still challenging for universal water electrolysis.Herein,we develop a double-cation etching strategy to tailor the electronic structure of NiMoO_(4),where the prepared NiMoO_(4) nanorods etched by H_(2)O_(2) reconstruct their surface with abundant cation deficiencies and lattice distortion.Calculation results reveal that the double cation deficiencies can make the upshift of d-band center for Ni atoms and the active sites with better oxygen adsorption capacity.As a result,the optimized sample(NMO-30M)possesses an overpotential of 260 mV at 10 mA cm−2 and excellent long-term durability of 162 h.Importantly,in situ Raman test reveals the rapid formation of high-oxidation-state transition metal hydroxide species,which can further help to improve the catalytic activity of NiMoO_(4) in OER.This work highlights the influence of surface remodification and shed some light on activating catalysts.

The opportunities and challenges of ionic liquids in perovskite solar cells

Metal halide perovskite solar cells(PSCs)have shown great potential to become the next generation of photovoltaic devices due to their simple fabrication techniques,low cost,and soaring power conversion efficiency(PCE).However,mismatched with the quickly updated PCEs,the improvement of device stability is challenging and still remains a critical hurdle in the path to commercialization.Recently,ionic liquids(ILs)have been found to play multiple roles in obtaining efficient and stable PSCs.These ILs usually consist of large organic cations and organic or inorganic anions,which have weak electrostatic attraction and are generally liquid at around 100℃.ILs are almost non-volatile,non-flammable,with high ionic conductivity and excellent thermal and electrochemical stability.The roles of ILs in PSCs vary with their composition,that is,the types of anions and cations.In this review,we summarize the roles of anions and cations in terms of precursor solutions,additives,perovskite/charge transport layer interface engineering,and charge transport layers.This article aims to set up a structure–property-stability-performance correlations conferred by the IL in PSC and provide assistance for the anion and cation selection for improving the quality of perovskite film,optimizing interface contact,reducing defect states,and improving charge extraction and transport characteristics.Finally,the application of IL in PSCs is discussed and prospected.

SF-CNN: Deep Text Classification and Retrieval for Text Documents

Researchers and scientists need rapid access to text documents such as research papers,source code and dissertations.Many research documents are available on the Internet and need more time to retrieve exact documents based on keywords.An efficient classification algorithm for retrieving documents based on keyword words is required.The traditional algorithm performs less because it never considers words’polysemy and the relationship between bag-of-words in keywords.To solve the above problem,Semantic Featured Convolution Neural Networks(SF-CNN)is proposed to obtain the key relationships among the searching keywords and build a structure for matching the words for retrieving correct text documents.The proposed SF-CNN is based on deep semantic-based bag-of-word representation for document retrieval.Traditional deep learning methods such as Convolutional Neural Network and Recurrent Neural Network never use semantic representation for bag-of-words.The experiment is performed with different document datasets for evaluating the performance of the proposed SF-CNN method.SF-CNN classifies the documents with an accuracy of 94%than the traditional algorithms.

Mango Pest Detection Using Entropy-ELM with Whale Optimization Algorithm

Image processing,agricultural production,andfield monitoring are essential studies in the researchfield.Plant diseases have an impact on agricultural production and quality.Agricultural disease detection at a preliminary phase reduces economic losses and improves the quality of crops.Manually identifying the agricultural pests is usually evident in plants;also,it takes more time and is an expensive technique.A drone system has been developed to gather photographs over enormous regions such as farm areas and plantations.An atmosphere generates vast amounts of data as it is monitored closely;the evaluation of this big data would increase the production of agricultural production.This paper aims to identify pests in mango trees such as hoppers,mealybugs,inflorescence midges,fruitflies,and stem borers.Because of the massive volumes of large-scale high-dimensional big data collected,it is necessary to reduce the dimensionality of the input for classify-ing images.The community-based cumulative algorithm was used to classify the pests in the existing system.The proposed method uses the Entropy-ELM method with Whale Optimization to improve the classification in detecting pests in agricul-ture.The Entropy-ELM method with the Whale Optimization Algorithm(WOA)is used for feature selection,enhancing mango pests’classification accuracy.Support Vector Machines(SVMs)are especially effective for classifying while users get var-ious classes in which they are interested.They are created as suitable classifiers to categorize any dataset in Big Data effectively.The proposed Entropy-ELM-WOA is more capable compared to the existing systems.

Dual-interlayers constructed by Ti_(3)C_(2)T_(x)/ionic-liquid for enhanced performance of solid garnet batteries

Li(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability.However,the inherent rigidity and brittleness of LLZTO lead to poor contact with anode/cathode and the operation failure of full cells.Herein,the dual-interlayers are constructed as the fast interfacial ion-migration channel by using Ti_(3)C_(2)T_(x)(MXene,Txis-O,-OH,-F) with trace ionic liquid(IL),which promote the intimate contact between LLZTO and anode/cathode and suppress Li-dendrites growth.Notably,IL can wet the cathode to promote intimate interface contact and be decomposed into some inorganic compounds(such as Li3N,LiF,and Li2Sx),resulting in reduced interfacial resistance and fast Li-ion transportation.Consequently,in the prepared Li-symmetric cell,the interfacial resistance on the anode side plunges to 33.1 Ω cm^(-2),and stably maintains over 1000 h without short circuit at 0.05 mA cm^(-2).The full cell of Li|LiFePO4delivers a high initial capacity of 158.52 mA h g^(-1)and outstanding retention of 90.18% after 100 cycles at 60℃ and 0.2 C.Our work provides an efficient strategy to design dual-interlayers between LLZTO and anode/cathode for the interfacial modification to enhance the performance of solid garnet batteries.

Addressing cation mixing in layered structured cathodes for lithium-ion batteries:A critical review

High-performance lithium-ion batteries(LIB)are important in powering emerging technologies.Cathodes are regarded as the bottleneck of increasing battery energy density,among which layered oxides are the most promising candidates for LIB.However,a limitation with layered oxides cathodes is the transition metal and Li site mixing,which significantly impacts battery capacity and cycling stability.Despite recent research on Li/Ni mixing,there is a lack of comprehensive understanding of the origin of cation mixing between the transition metal and Li;therefore,practical means to address it.Here,a critical review of cation mixing in layered cathodes has been provided,emphasising the understanding of cation mixing mechanisms and their impact on cathode material design.We list and compare advanced characterisation techniques to detect cation mixing in the material structure;examine methods to regulate the degree of cation mixing in layered oxides to boost battery capacity and cycling performance,and critically assess how these can be applied practically.An appraisal of future research directions,including superexchange interaction to stabilise structures and boost capacity retention has also been concluded.Findings will be of immediate benefit in the design of layered cathodes for high-performance rechargeable LIB and,therefore,of interest to researchers and manufacturers.

Propelling polysulfide redox by Fe_(3)C-FeN heterostructure@nitrogendoped carbon framework towards high-efficiency Li-S batteries

Lithium-sulfur(Li-S) batteries hold great promise in next-generation high-energy-density energy storage systems,but the intractable shuttle effect and the sluggish redox kinetics of polysulfides hinder the practical implementation of Li-S batteries.Here,heterostructured Fe_(3)C-FeN nanoparticles dotted in the threedimensional-ordered nitrogen-doped carbon framework(Fe_(3)C-FeN@NCF) were synthesized by molecular engineering combined with heterointerface engineering,and were applied to regulate the immobilization-diffusion-conversion behavior of polar polysulfides.It is experimentally and theoretically demonstrated that the heterointerface between Fe_(3)C and FeN exhibits high sulfiphilicity and high electronic/ionic conductivity,thus effectively capturing polysulfides and accelerating the bidirectional conversion of sulfur species.Meanwhile,the holey carbon framework functions as the scaffold to highly disperse binary nanoparticles,ensuring the sufficient exposure of active sites and the easy accessibility for lithium ions and electrons.By virtue of these synergistic merits,the Li-S batteries based on Fe_(3)CFeN@NCF-modified separators afford excellent electrochemical performances including a high rate capacity of 858 mA h g^(-1)at 2 C and a low capacity decay rate of 0.07% per cycle after 800 cycles at 1C This work provides inspiration for the design of heterostructured compounds and sheds light on the potential of heterostructure in high-efficiency Li-S batteries.