Hydrogen sulfide responsive nanoplatforms: Novel gas responsive drug delivery carriers for biomedical applications

Hydrogen sulfide(H_(2)S)is a toxic,essential gas used in various biological and physical processes and has been the subject of many targeted studies on its role as a new gas transmitter.These studies have mainly focused on the production and pharmacological side effects caused by H_(2)S.Therefore,effective strategies to remove H_(2)S has become a key research topic.Furthermore,the development of novel nanoplatforms has provided new tools for the targeted removal of H_(2)S.This paper was performed to review the association between H_(2)S anddisease,relatedH_(2)S inhibitory drugs,aswell as H_(2)S responsive nanoplatforms(HRNs).This review first analyzed the role of H_(2)S in multiple tissues and conditions.Second,common drugs used to eliminate H_(2)S,as well as their potential for combination with anticancer agents,were summarized.Not only the existing studies on HRNs,but also the inhibition H_(2)S combined with different therapeutic methods were both sorted out in this review.Furthermore,this review provided in-depth analysis of the potential of HRNs about treatment or detection in detail.Finally,potential challenges of HRNs were proposed.This study demonstrates the excellent potential of HRNs for biomedical applications.

Lysine demethylase 5B transcriptionally regulates TREM1 in human cardiac fibroblasts

Background:A differential gene,triggering receptor expressed on myeloid cells 1(TREM1),was identified in blood sequencing datasets from myocardial infarction patients and healthy controls.Myocardialfibrosis following myocardial infarction significantly contributes to cardiac dysfunction.Objectives:This study aimed to unveil the intrinsic regulatory mechanism of TREM1 in myocardialfibrosis.Methods:Mimicking pathology by angiotensin II(Ang II)treatment of human cardiacfibroblasts(HCFs),the impacts of TREM1 knockdown on its proliferation,migration,and secretion of the pro-fibrotic matrix were identified.Using the Human Transcription Factor Database(HumanTFDB)website,lysine-specific demethylase 5B(KDM5B)was found to bind to the TREM1 promoter,which was further validated through luciferase reporter and chromatin immunoprecipitation(ChIP).By promoting KDM5B overexpression,its effect on the regulation of TREM1 was examined.Results:TREM1 knockdown suppressed the proliferation,migration,and secretion of the pro-fibrotic matrix in HCFs upon Ang II treatment.KDM5B bound to the TREM1 promoter and upregulated its transcriptional expression.Furthermore,KDM5B overexpression reversed the regulation of the above cellular phenotypes by TREM1 knockdown.Conclusion:This study sheds light on the positive regulation of TREM1 by KDM5B,demonstrating their role in promoting myocardialfibrosis.Thisfinding provides a theoretical foundation for understanding disease pathology and potentially advancing the development of new targeted therapies.

CoS_(2)nanowires supported graphdiyne for highly efficient hydrogen evolution reaction

Transition metal sulfides are an important category for hydrogen evolution reaction(HER).However,only few edge unsaturated sulfurs functionalize as catalytic sites,which has dramatically limited the catalytic activity and stability.In this work,planar unsaturated sulfurs in(211)plane of the CoS_(2)nanowires have been successfully activated through constructing Graphdiyne-CoS_(2)heterojunction nanocomposites.The corresponding electrons transfer energy barriers for these planar unsaturated sulfurs have been significantly diminished,which are induced by the synergetic effects of the sp~1 hybridized carbons and unsaturated planar sulfurs.In addition,DFT simulations reveal the synergetic effects of the sp~1 hybridized carbons and unsaturated planar sulfurs can promote electron transfer kinetics of the key step,VolmerHeyrovsky step,of the reaction.As expected,the Graphdiyne-CoS_(2)heterojunction nanocomposites exhibit superior HER catalytic performance with low overpotential of 97 mV at 10 mA cm^(-2),and the Tafel slope of 56 mV dec^(-1).Furthermore,the heterojunction shows outstanding stability as well due to the pr tection of the Graphdiyne(GDY).The approach thus paves the way for the further efficient transition metal disulfides catalyst manufactures.

A general strategy to the synthesis of carbon-supported PdM(M=Co,Fe and Ni)nanodendrites as high-performance electrocatalysts for formic acid oxidation

Rational synthesis of a new class of electrocatalysts with high-performance and low-cost is of great significance for future fuel cell devices. Herein, we demonstrate a general one-step simultaneous reduction method to prepare carbon-supported Pd M（M = Co, Fe, Ni） alloyed nanodendrites with the assistance of oleylamine and octadecylene. The morphology, structure and composition of the obtained Pd M nanodendrites/C catalysts have been fully characterized. The combination of the dendritic structural feature and alloyed synergy offer higher atomic utilization efficiency, excellent catalytic activity and enhanced stability for the formic acid oxidation reaction（FAOR）. Strikingly, the as-synthesized Pd Co nanodendrites/C catalyst could afford a mass current density of 2467.7 A g, which is almost 3.53 and 10.4 times higher than those of lab-made Pd/C sample(698.3 A g) and commercial Pd/C catalyst(237.6 A g), respectively. Furthermore, the PdC o nanodendrites/C catalyst also exhibit superior stability relative to the Pd/C catalysts, make it a promising anodic electrocatalyst in practical fuel cells in the future. Additionally, the present feasible synthetic approach is anticipated to provide a versatile strategy toward the preparation of other metal alloy nanodendrites/carbon nanohybrids.

Coarse-grained simulations on interactions between spectrins and phase-separated lipid bilayers

Spectrin, the principal protein of the cytoskeleton of erythrocyte, plays a crucial role in the stability and flexibility of the plasma membrane of erythrocyte. In this work, we investigate the interactions between spectrins and phase-separated lipid bilayers using coarse-grained molecular dynamics simulation. We focus on the preference of spectrins with different lipids, the effects of the anionic lipids and the residue mutation on the interactions between spectrins and the lipid bilayers. The results indicate that spectrins prefer to contact with phosphatidylethanolamine(PE) lipids rather than with phosphatidylcholine(PC) lipids, and tend to contact with the liquid-disordered(Ld) domains enriched in unsaturated PE.Additionally, the anionic lipids, which show specific interaction with the positively charged or polar amino acids on the surface of the spectrins, can enhance the attraction between the spectrins and lipid domains. The mutation leads to the decrease of the structural stability of spectrins and increases the curvature of the lipid bilayer. This work provides some theoretical insights into understanding the erythrocyte structure and the mechanism of some blood diseases.

Chemical composition of oscillatory zoned garnets from the largescale Mengya'a Pb–Zn skarn deposit: implications for fluid physicochemical conditions and formation

The Mengya’a Lead–zinc deposit is a large skarn deposit in the north of the eastern segment of Gangdese metallogenic belt.The garnet is the main altered mineral in the Mengya’a area.The color of the garnet varies from chartreuse to dark yellow brown and to russet.The brown garnet(Grt1)is related to pyrrhotite and chalcopyrite,and the green garnet(Grt2)is associated with lead–zinc mineralization.LA-ICP-MS is the induced coupled plasma mass spectrometry.This paper has used this technique to investigate Grt1 and Grt2.Grt1 develops core–rim textures with strong oscillation zone occurring in rim,whereas Grt2lacks core–rim textures and featured by oscillation zone.LA–ICP–MS analysis shows that garnets of Mengya’a are rich in CaO(29.90–37.52%)and FeO(21.17–33.35%),but low in Al_(2)O_(3)(0.05–4.85%).The calculated end members belong to grandite(grossular–andradite)garnets andradite.The negative Al(IV)versus Fe^(3+),positive Al(IV)versus total Al stoichiometric number,the positive Al(IV)versus Fe^(3+),and the negative Al(IV)versus total REE,all indicate that the substitution of REEs in garnets is controlled by YAG.All Garnets are depleted in large lithophile elements(e.g.,Rb=0.00–4.01 ppm,Sr=0.03–8.56 ppm).The total REE in Grt1 core is high(ΣREE=233–625 ppm),with HREE enriched pattern(LREE/HREE=0.33–1.69)and weak negative Eu anomalies(δEu=0.21–0.47).In contrast,the total REEs in the Grt1 rim and Grt2 are low(ΣREE=12.4–354 ppm;ΣREE=21.0–65.3 ppm),with LREE enriched pattern(LREE/HREE=0.54–34.4;LREE/HREE=11.4–682)and positive Eu anomalies(δEu=0.35–27.2;δEu=1.02–30.7).After data compilation of garnet chemicals,we found that the early fluid responsible for the core of Grt1 was a relatively closed and chloride-depleted fluid system.It was close-to-neutral,with a low water–rock ratio.The core of garnet was formed by fluid diffusion in metasomatic processes.The fluid was changed into a relatively open system with reduced,chloride-rich,and weakacid fluid.It was fluid infiltration and metasomatism that resulted in the formation of Grt1 rim and Grt2.

Two-dimensional transition metal MXene-based gas sensors:A review

As an emerging star in the family of two-dimensional(2D)materials,2D transition metal carbides,carbonitrides and nitrides,collectively referred to as MXenes,have large specific surface area,rich active sites,metallic conductivity and adjustable surface chemical properties.These features make MXenes promising candidates for gas-sensing materials.For the past few years,MXene-based sensors have drawn increasing attention due to their enhanced sensor performance.Based on this,this review systematically represents the structure,synthesis methods and properties of MXenes,and summarizes their applications in gas sensors.Firstly,the types,structure,main synthesis methods and properties of MXenes are introduced in a comprehensive way.Next,the corresponding design principle and working mechanism of MXene-based gas sensor are clarified.Subsequently,the sensing performances of pristine MXenes and the MXene-based nanocomposite are discussed.Finally,some future opportunities and challenges of MXene-based sensors are pointed out.

Phenolic-enabled nanotechnology:a new strategy for central nervous system disease therapy

Polyphenolic compounds have received tremendous attention in biomedicine because of their good biocompatibility and unique physicochemical properties.In recent years,phenolic-enabled nanotechnology(PEN)has become a hotspot of research in the medical field,and many promising studies have been reported,especially in the application of central nervous system(CNS)diseases.Polyphenolic compounds have superior anti-inflammatory and antioxidant properties,and can easily cross the blood‒brain barrier,as well as protect the nervous system from metabolic damage and promote learning and cognitive functions.However,although great advances have been made in this field,a comprehensive review regarding PEN-based nanomaterials for CNS therapy is lacking.A systematic summary of the basic mechanisms and synthetic strategies of PEN-based nanomaterials is beneficial for meeting the demand for the further development of novel treatments for CNS diseases.This review systematically introduces the fundamental physicochemical properties of PEN-based nanomaterials and their applications in the treatment of CNS diseases.We first describe the different ways in which polyphenols interact with other substances to form high-quality products with controlled sizes,shapes,compositions,and surface chemistry and functions.The application of PEN-based nanomaterials in the treatment of CNS diseases is then described,which provides a reference for subsequent research on the treatment of CNS diseases.

The blood-brain barrier:structure,regulation,and drug delivery

Blood–brain barrier(BBB)is a natural protective membrane that prevents central nervous system(CNS)from toxins and pathogens in blood.However,the presence of BBB complicates the pharmacotherapy for CNS disorders as the most chemical drugs and biopharmaceuticals have been impeded to enter the brain.Insufficient drug delivery into the brain leads to low therapeutic efficacy as well as aggravated side effects due to the accumulation in other organs and tissues.Recent breakthrough in materials science and nanotechnology provides a library of advanced materials with customized structure and property serving as a powerful toolkit for targeted drug delivery.In-depth research in the field of anatomical and pathological study on brain and BBB further facilitates the development of brain-targeted strategies for enhanced BBB crossing.In this review,the physiological structure and different cells contributing to this barrier are summarized.Various emerging strategies for permeability regulation and BBB crossing including passive transcytosis,intranasal administration,ligands conjugation,membrane coating,stimuli-triggered BBB disruption,and other strategies to overcome BBB obstacle are highlighted.Versatile drug delivery systems ranging from organic,inorganic,and biologics-derived materials with their synthesis procedures and unique physio-chemical properties are summarized and analyzed.This review aims to provide an up-to-date and comprehensive guideline for researchers in diverse fields,offering perspectives on further development of brain-targeted drug delivery system.

Microbial community structures in an integrated two-phase anaerobic bioreactor fed by fruit vegetable wastes and wheat straw

The microbial community structures in an integrated two-phase anaerobic reactor（ITPAR）were investigated by 16 S r DNA clone library technology. The 75 L reactor was designed with a 25 L rotating acidogenic unit at the top and a 50 L conventional upflow methanogenic unit at the bottom, with a recirculation connected to the two units. The reactor had been operated for 21 stages to co-digest fruit/vegetable wastes and wheat straw, which showed a very good biogas production and decomposition of cellulosic materials. The results showed that many kinds of cellulose and glycan decomposition bacteria related with Bacteroidales,Clostridiales and Syntrophobacterales were dominated in the reactor, with more bacteria community diversities in the acidogenic unit. The methanogens were mostly related with Methanosaeta, Methanosarcina, Methanoculleus, Methanospirillum and Methanobacterium; the predominating genus Methanosaeta, accounting for 40.5%, 54.2%, 73.6% and 78.7% in four samples from top to bottom, indicated a major methanogenesis pathway by acetoclastic methanogenesis in the methanogenic unit. The beta diversity indexes illustrated a more similar distribution of bacterial communities than that of methanogens between acidogenic unit and methanogenic unit. The differentiation of methanogenic community composition in two phases, as well as pH values and volatile fatty acid（VFA） concentrations confirmed the phase separation of the ITPAR. Overall, the results of this study demonstrated that the special designing of ITPAR maintained a sufficient number of methanogens, more diverse communities and stronger syntrophic associations among microorganisms, which made two phase anaerobic digestion of cellulosic materials more efficient.

Photothermal/matrix metalloproteinase-2 dual-responsive gelatin nanoparticles for breast cancer treatment

The chemotherapy combined with photothermal therapy has been a favorable approach for the treatment of breast cancer.In present study,nanoparticles with the characteristics of photothermal/matrix metalloproteinase-2(MMP-2)dual-responsive,tumor targeting,and size-variability were designed for enhancing the antitumor efficacy and achieving"on-demand"drug release markedly.Based on the thermal sensitivity of gelatin,we designed a size-variable gelatin nanoparticle(GNP)to encapsulate indocyanine green(ICG)and doxorubicin(DOX).Under an 808 nm laser irradiation,GNP-DOX/ICG responded photothermally and swelled in size from 71.58?4.28 to 160.80?9.51 nm,which was beneficial for particle retention in the tumor sites and release of the loaded therapeutics.Additionally,GNP-DOX/ICG showed a size reduction of the particles to 33.24?4.11 nm and further improved drug release with the degradation of overexpressed MMP-2 in tumor.In the subsequently performed in vitro experiments,it was confirmed that GNP-DOX/ICG could provide a therapeutic effect that was enhanced and synergistic.Consequently,GNP-DOX/ICG could efficiently suppress the growth of 4 T1 tumor in vivo.In conclusion,this study may provide a promising strategy in the rational design of drug delivery nanosystems based on gelatin for chemo-photothermal therapy to achieve synergistically enhanced therapeutic efficacy against breast cancer.

干旱区绿洲耕地撂荒与复耕对土壤水力性质的影响

土地利用变化会改变土壤质地与结构,影响土壤水力性质,进而改变土壤水分有效性,影响植物生长。由于区域气候的干湿交替与水资源利用效率的提高,干旱区绿洲耕地普遍存在着撂荒-复耕现象。为了明确干旱区耕地撂荒与复耕对土壤水力性质的影响,以民勤绿洲北部边缘的耕地、撂荒地与撂荒复耕地为研究对象,测定0—40 cm深度土壤理化性质,分析不同土地利用下土壤水力性质差异及其影响因素。结果表明:耕地撂荒导致0—40 cm深度黏粒与粉粒比重增加,有机质含量降低,容重降低(P<0.05),土壤孔隙度显著增加(P<0.05),犁底层消失;在高水势阶段,土壤持水与导水能力增强,在土壤有效含水量对应的水势阶段,土壤持水与导水能力变差,有效含水量显著降低(P<0.05)。撂荒地复耕后,0—40 cm深度黏粒与粉粒含量继续增加,有机质含量转而增加,容重增加(P<0.05),土壤孔隙度降低(P<0.05),犁底层重新出现,土壤持水与导水能力又逐渐趋向于耕地水平。撂荒对干旱区绿洲土壤肥力与蓄水能力的提升不显著,而留茬免耕、深耕灭茬还田等保护性耕作措施能有效提高持水能力。利用研究区易测的土壤黏粒、砂粒含量与土壤容重,采用多元线性回归方法,可以准确、快捷预测土壤水分常数,这将有利于研究区农田灌溉制度的准确制定与优化,以及耕地利用变化对土壤水力性质影响的快速评估。

Methanogenic community dynamics in anaerobic co-digestion of fruit and vegetable waste and food waste

A lab-scale continuously-stirred tank reactor （CSTR）, used for anaerobic co-digestion of fruit and vegetable waste （FVW） and food waste （FW） at different mixture ratios, was operated for 178 days at the organic loading rate of 3 kg VS （volatile solids）/（m3.day）. The dynamics of the Archaeal community and the correlations between environmental variables and methanogenic community structure were analyzed by polymerase chain reactions - denaturing gradient gel electrophoresis （PCR-DGGE） and redundancy analysis （RDA）, respectively. PCR-DGGE results demonstrated that the mixture ratio of FVW to FW altered the community composition of Archaea. As the FVW]FW ratio increased, Methanoculleus, Methanosaeta and Methanosarcina became the predominant methanogens in the community. Redundancy analysis results indicated that the shift of the methanogenic community was significantly correlated with the composition of acidogenic products and methane production yield. Different mixture ratios of substrates led to different compositions of intermediate metabolites, which may affect the methanogenic community. These results suggested that the analysis of microbial communities could be used to diagnose anaerobic processes.

Cooperative coordination-mediated multi-component self-assembly of“all-in-one”nanospike theranostic nano-platform for MRI-guided synergistic therapy against breast cancer

Carrier-free multi-component self-assembled nano-systems have attracted widespread attention owing to their easy preparation,high drug-loading efficiency,and excellent therapeutic efficacy.Herein,MnAs-ICG nanospike was generated by self-assembly of indocyanine green(ICG),manganese ions(Mn^(2+)),and arsenate(AsO_(4)^(3−))based on electrostatic and coordination interactions,effectively integrating the bimodal imaging ability of magnetic resonance imaging(MRI)and fluorescence(FL)imaging-guided synergistic therapy of photothermal/chemo/chemodynamic therapy within an“all-in-one”theranostic nano-platform.The as-prepared MnAs-ICG nanospike had a uniform size,well-defined nanospike morphology,and impressive loading capacities.The MnAs-ICG nanospike exhibited sensitive responsiveness to the acidic tumor microenvironment with morphological transformation and dimensional variability,enabling deep penetration into tumor tissue and on-demand release of functional therapeutic components.In vitro and in vivo results revealed that MnAs-ICG nanospike showed synergistic tumor-killing effect,prolonged blood circulation and increased tumor accumulation compared to their individual components,effectively resulting in synergistic therapy of photothermal/chemo/chemodynamic therapy with excellent anti-tumor effect.Taken together,this new strategy might hold great promise for rationally engineering multifunctional theranostic nano-platforms for breast cancer treatment.

Microwave triggered multifunctional nanoplatform for targeted photothermal-chemotherapy in castration-resistant prostate cancer

Lacking a precise targeting strategy,castration-resistant prostate cancer(CRPC)is still hard to be treat effectively.Exploring treatment options that can accurately target CPRC is an important issue with urgent need.In this study,a novel nanotechnologybased strategy had been developed for the precise target treatment of CRPC.By combining microwaves and photothermal therapy(PTT),this nanoplatform,cmHSP70-PL-AuNC-DOX,targets tumor tissues with outstanding precision and achieves better anti-tumor activity by simultaneously eliciting photothermal and chemotherapeutic effects.From nanotechnology,cmHSP70-modified and thermo-sensitive liposome-coated AuNC-DOX were prepared and used for CRPC-targeted photothermal ablation and chemotherapy.Doxorubicin(DOX)was selected as the chemotherapeutic agent for cytotoxicity.In terms of the curative scheme,prostate tissues were firstly pre-treated with microwaves to induce the expression of heat shock protein 70(HSP70)and its migration to the cell membrane,which was then targeted by HSP70 antibody(cmHSP70)coated on the nanoparticles to achieve accurate drug delivery.The nanoplatform then achieved precise ablation and controlled release of DOX under external near-infrared(NIR)irradiation.Through the implementation,the targeting,cell killing,and safety of this therapeutical strategy had been verified in vivo and in vitro.This work establishes an accurate,controllable,efficient,non-invasive,and safe treatment platform for targeting CRPC,provides a rational design for CRPC’s PTT,and offers new prospects for nanomedicines with great precision.

Rational design of robust iridium-ceria oxide-carbon nanofibers to boost oxygen evolution reaction in both alkaline and acidic media

Anodic oxygen evolution reaction(OER)is essential to participate in diverse renewable energy conversion and storage processes,while most OER electrocatalysts present satisfactory catalytic performance in only alkaline or acidic medium,limiting their practical applications in many aspects.Herein,we have designed and prepared Ir-CeO_(2)-C nanofibers(NFs)via an electrospinning and a relatively low-temperature calcination strategy for OER application in both alkaline and acidic conditions.Density functional theory(DFT)simulations demonstrate the high catalytic active sites of Ir atoms for OER,that the formation of Ir–O bonds at the interface between Ir and CeO_(2)can modulate the electron density of the relevant Ir atoms to promote the OER activity.In addition,the unique nanofibrous heterostructure increases the exposed active sites and promotes the electrical conductivity.Therefore,the prepared Ir-CeO_(2)-C nanofibrous catalyst delivers an excellent OER property in both alkaline and acidic solutions.Impressively,the overpotentials to reach 10 mA·cm^(−2)are only 279 and 283 mV in the alkaline and acidic electrolyte,respectively,with favorable long-term stabilities.In addition,the two-electrode overall water splitting set-ups equipped with Ir-CeO_(2)-C NFs as anode and commercial Pt/C as cathode provide a cell voltage of 1.54 and 1.53 V to drive 10 mA·cm^(−2)in the alkaline and acidic electrolyte,respectively,which are much lower than Pt/C||IrO_(2)and lots of transition metal oxides-based electrolyzers.This research presents an efficient means to design OER catalysts with superior properties in both alkaline and acidic solutions.

CircRNA.0007127 triggers apoptosis through the miR-513a-5p/CASP8 axis in K-562 cells

Background:Circular RNAs(circR NAs)are covalently closed single-stranded RNAs with multiple biological functions.CircRNA.0007127 is derived from the carbon catabolite repression 4-negative on TATA-less(CCR4-NOT)complex subunit2(CNOT2),which was found to regulate tumor cell apoptosis through caspase pathway.Methods:Potential circR NA.0007127 target microRNAs(miRNAs)were analyzed by miRanda,TargetScan,and RNAhybrid software,and the miRNAs with binding sites for apoptosis-related genes were screened.The roles of circR NA.0007127 and its downstream target,microR NA(miR)-513a-5p,were validated by quantitative real-time polymerase chain reaction(qPCR),flow cytometry,mitochondrial membrane potential,immunofluorescence,western blot,and caspase-8(CASP8)protein activity in vitro in HO-induced K-562 cells.The circRNA.0007127-miR-513a-5p and CASP8-miR-513a-5p interactions were verified by luciferase reporter assays.Results:Silencing circRNA.0007127 decreased cell apoptosis by inhibiting CASP8 pathway activation in K-562 cells.Compared with the control group,the expression of CASP8 was reduced by 50%and the 43-kD fragment of CASP8 protein was significantly reduced(P≤0.05).The luciferase reporting assay showed that circRNA.0007127 combined with miR-513a-5p or CASP8,with extremely significant differences(P≤0.001).The overexpression of miR-513a-5p inhibited the gene expression level of CASP8in a human myeloid leukemia cell model(75%change)and the level of a 43-kD fragment of CASP8 protein(P small-interfering RNA(siRNA)and the miR-≤0.01).The rescue experiment showed that cotransfection with circRNA.0007127513a-5p inhibitor increased CASP8 gene expression and the apoptosis rate,suggesting that the miR-513a-5p inhibitor is a circRNA.0007127siRNA antagonist.Conclusions:CircRNA.0007127 regulates K-562 cell apoptosis through the miR-513a-5p/CASP8 axis,which can serve as a novel powerful molecular target for K-562 cells.

Hybridized Local and Charge-Transfer Excited-State Fluorophores through the Regulation of the Donor-Acceptor Torsional Angle for Highly Efficient Organic Light-Emitting Diodes

Hybridized local and charge-transfer(HLCT)excitedstate fluorophores,which enable full exciton utilization through a reverse intersystem crossing fromhigh-lying triplet states to singlet state,have attracted increasing attention toward organic light-emitting diodes(OLEDs)application.Herein,we report three D-π-A-π-D-type isomers o-2CzBT,m-2CzBT,and p-2CzBT by adjusting the donor(D)units from ortho-,meta-,to para-substituted positions with the acceptor(A)core unit,respectively.The HLCT properties of the three compounds are evidently confirmed by theoretical calculations,solvatochromic behaviors,and transient decay lifetimes analyses.As the substituted position changes from the ortho-,meta-,and para-positions,the reduced steric hindrance brings about decreased torsional angle between D and A moieties,resulting in increased oscillator strength.Accordingly,the parasubstituted p-2CzBT is endowed with a more locally excited component that accounts for faster radiative decay,leading to a higher fluorescent efficiency than that of o-2CzBT and m-2CzBT.As expected,p-2CzBT enables its nondoped and doped OLEDs with higher external quantum efficiencies(EQEs)of 12.3% and 15.0%,respectively,which are among the state-ofthe-art efficiencies of HLCT-based OLEDs.Moreover,o-2CzBT and m-2CzBT are also utilized as host materials for high-performance OLEDs,thus extending the application of HLCT materials.

负载在Co/碳纳米纤维上的分层非晶双金属硫化物纳米片用于协同促进水电解

设计分层异质结构作为一种经济且高效的催化剂,以实现水分解的电子和界面工程,是能源存储与转化中的一个有意义的决策.在这项工作中,通过静电纺丝-碳化-电沉积的策略,制备了负载在嵌入Co纳米颗粒的碳纤维上的非晶态NiFeS纳米片(Co-C/NiFeS纳米纤维)催化剂.该催化剂具有优异的析氧反应(OER)活性,在1 mol L^(-1)KOH溶液中,在10 mA cm^(-2)下的过电位为233 mV,Tafel斜率为53.1 mV dec^(-1),同时还具有良好的析氢反应活性.此外,由Co-C/NiFeS纳米纤维作为阳极,商用Pt/C作为阴极构建的碱性Pt/C‖Co-C/NiFeS电解槽在10 mA cm^(-2)下实现1.48 V的低电池电压,优于基准Pt/C‖RuO_(2)电解槽和许多其他报道的电解槽.作为双功能电催化剂,Co-C/NiFeS‖Co-C/NiFeS自身组装的电解槽表现出70小时的长期稳定性,显著优于Pt/C‖RuO_(2)电解槽.该催化剂显著的OER性能得益于Co-C纳米纤维核与非晶NiFeS纳米片鞘组成的明显分层异质结构以及生成的高导电碳纤维基底,这些结构特征赋予该材料丰富的暴露活性位点、良好的导电性和坚固的结构稳定性.因此,这项工作提出了一种简单且有效的方法来制备具有优异电催化性能的非贵金属基催化剂,以用于实际的能量转换和存储.

Interactions between amphiphilic nanoparticles coated with striped hydrophilic/hydrophobic ligands and a lipid bilayer

Due to their unique physicochemical properties,nanoparticles play an important role in the fields of nanomedicine and so on.In this paper,the interactions between the nanoparticles coated with striped hydrophilic and hydrophobic ligands and a lipid bilayer are investigated by using the coarse-grained molecular dynamics simulation.This study focuses on the effects of the density of the ligands,the ratio of the hydrophilic ligands to the hydrophobic ligands,and the rigidity of the ligands on the interactions of the nanoparticles with the lipid bilayer.The results show that the nanoparticles interact with the lipid bilayer in two different ways.The nanoparticle with a small size,a large ratio of hydrophilic ligands to the hydrophobic ligands,and flexible ligands can readily be inserted into the lipid bilayer,and the nanoparticle rotation is very crucial to the insertion of the nanoparticle into the bilayer.However,the nanoparticle with a large size,a small ratio of hydrophilic ligands to hydrophobic ligands,and rigid ligands can only be adsorbed on the surface of the lipid bilayer.This work provides an effective method to modulate the interactions of the amphiphilic nanoparticles with the lipid bilayers and some insights into the applications of the nanoparticles in drug delivery,cell imaging,etc.