A Single-Layer Piezoelectric Composite Separator for Durable Operation of Li Metal Anode at High Rates

Piezoelectric ceramic and polymeric separators have been proposed to effectively regulate Li deposition and suppress dendrite growth,but such separators still fail to satisfactorily support durable operation of lithium metal batteries owing to the fragile ceramic layer or low-piezoelectricity polymer as employed.Herein,by combining PVDF-HFP and ferroelectric BaTiO_(3),we develop a homogeneous,single-layer composite separator with strong piezoelectric effects to inhibit dendrite growth while maintaining high mechanical strength.As squeezed by local protrusion,the polarized PVDF-HFP/BaTiO_(3)composite separator generates a local voltage to suppress the local-intensified electric field and further deconcentrate regional lithium-ion flux to retard lithium deposition on the protrusion,hence enabling a smoother and more compact lithium deposition morphology than the unpoled composite separator and the pure PVDF-HFP separator,especially at high rates.Remarkably,the homogeneous incorporation of BaTiO_(3)highly improves the piezoelectric performances of the separator with residual polarization of 0.086 pC cm^(-2)after polarization treatment,four times that of the pure PVDF-HFP separator,and simultaneously increases the transference number of lithium-ion from 0.45 to 0.57.Beneficial from the prominent piezoelectric mechanism,the polarized PVDF-HFP/BaTiO_(3)composite separator enables stable cyclic performances of Li||LiFePO_(4)cells for 400 cycles at 2 C(1 C=170 mA g^(-1))with a capacity retention above 99%,and for 600 cycles at 5 C with a capacity retention over 85%.

Exploration and Practice of Integrating Ideological and Political Education into the“Comprehensive Practical Training in Prefabricated Building Construction”Course

This paper focuses on the ideological and political construction of the course“Comprehensive Practical Training of Prefabricated Building Construction”and deeply discusses its exploration and practice process.By building an ideological and political teaching system in line with the characteristics of“Comprehensive Training of Prefabricated Building Construction,”ideological and political elements such as industry spirit,professional ethics,and social responsibility are organically integrated into all links of practical training and teaching.In terms of teaching methods,various innovative means such as case analysis,role-playing,and group discussion are adopted,and modern information technologies such as virtual reality and augmented reality are used to improve the teaching effect.At the same time,a diversified teaching evaluation system is formulated to ensure the sustainability and effectiveness of ideological and political education.This study not only enriches the theoretical research of ideological and political courses but also provides a practical reference for the ideological and political construction of similar courses,which is of great significance for promoting the overall improvement of the quality of talent training in higher education.

Digital Application Objectives and Benefit Analysis of BIM Technology in Large-Scale Comprehensive Development Projects

This paper discusses the digital application and benefit analysis of building information model(BIM)technology in the large-scale comprehensive development project of the Guangxi headquarters base.The project covers a total area of 92,100 square meters,with a total construction area of 379,700 square meters,including a variety of architectural forms.Through three-dimensional modeling and simulation analysis,BIM technology significantly enhances the design quality and efficiency,shortens the design cycle by about 20%,and promotes the collaboration and integration of project management,improving the management efficiency by about 25%.During the construction phase,the collision detection and four-dimensional visual management functions of BIM technology have improved construction efficiency by about 15%and saved the cost by about 10%.In addition,BIM technology has promoted green building and sustainable development,achieved the dual improvement of technical and economic indicators and social and economic benefits,set an example for enterprises in digital transformation,and opened up new market businesses.

Digital Application of BIM Technology in the Architectural Design Stage

This paper discusses the digital application of building information model(BIM)technology in the architectural design stage.Taking the large-scale comprehensive development project of Guangxi headquarters base as an example,this paper analyzes in detail how BIM technology promotes the intelligence and refinement of the design process.Through the threedimensional modeling and simulation analysis of BIM technology,the project design has realized the accurate transformation from concept to operation,which not only improves the design efficiency,but also ensures the construction quality and economic benefits.This paper focuses on the application of BIM in the digital design of building structure,the deepening design of steel nodes,as well as the remarkable results in the comprehensive layout optimization of mechanical and electrical pipelines.Through the collision detection and optimization design of the BIM model,the potential design conflicts and construction problems were found and solved at the initial stage of the project,ensuring the efficient promotion and smooth implementation of the project.The research results show that BIM technology,as the core digital tool in the architectural design stage,is of great significance for improving the overall design level of the construction industry and realizing intelligent construction.

索授式授课模式在大学化学课程中的教学尝试

基于在高等院校进行大学化学课程教学的重要意义和目前的教学现状,提出了包括知识预留、学生预习、提出问题、教师讲授、课堂讨论五个过程的索授式授课模式,并在大学化学课程中进行了教学尝试。应用结果表明索授式授课模式在激发学生学习的主动性、提高学生知识掌握的有效率、培养学生的学习能力等方面起到了关键作用。并根据教学实践效果,从生理学、心理学、哲学、教育学和社会学角度,讨论了索授式授课模式的理论应用意义,希望对我国高校课堂教学有借鉴作用。

Oncolytic Virus Senecavirus A Inhibits Hepatocellular Carcinoma Proliferation and Growth by Inducing Cell Cycle Arrest and Apoptosis

Background and Aims:Hepatocellular carcinoma(HCC)isa highly aggressive tumor with limited treatment options andhigh mortality.Senecavirus A(SVA)has shown potential inselectively targeting tumors while sparing healthy tissues.This study aimed to investigate the effects of SVA on HCCcells in vitro and in vivo and to elucidate its mechanisms ofaction.Methods:The cell counting kit-8 assay and colonyformation assay were conducted to examine cell proliferation.Flow cytometry and nuclear staining were employed toanalyze cell cycle distribution and apoptosis occurrence.Asubcutaneous tumor xenograft HCC mouse model was createdin vivo using HepG2 cells,and Ki67 expression in thetumor tissues was assessed.The terminal deoxynucleotidyltransferase dUTP nick end labeling assay and hematoxylinand eosin staining were employed to evaluate HCC apoptosisand the toxicity of SVA on mouse organs.Results:In vitro,SVA effectively suppressed the growth of tumor cells by inducingapoptosis and cell cycle arrest.However,it did nothave a notable effect on normal hepatocytes(MIHA cells).In an in vivo setting,SVA effectively suppressed the growthof HCC in a mouse model.SVA treatment resulted in a significantdecrease in Ki67 expression and an increase in apoptosisof tumor cells.No notable histopathological alterationswere observed in the organs of mice during SVA administration.Conclusions:SVA inhibits the growth of HCC cells byinducing cell cycle arrest and apoptosis.It does not causeany noticeable toxicity to vital organs.

Talcum-doped composite separator with superior wettability and heatproof properties for high-rate lithium metal batteries

Separator is supposed to own outstanding thermal stability,superior wettability and electrolyte uptake,which is essential for developing high-rate and safe lithium metal batteries(LMBs).However,commercial polyolefin separators possess poor wettability and limited electrolyte uptake.For addressing this issue,we put forward a composite separator to implement above functions by doping layered-silicate(talcum)into polyvinylidene fluoride(PVDF).With significant improvement of electrolyte absorption benefiting from the strong adsorption energy values(-1.64-1.70 eV)between talcum and the electrolyte in lithium metal batteries,PVDF/Talcum(PVDF/TM)composite separator owns a small contact angle and superior electrolyte uptake.PVDF/TM composite separator with 10 wt%talcum(T-10)owns a tiny contact angle of 8°,while those of polypropylene(PP)and PVDF are 48°and 20°with commercial electrolyte.Moreover,the addition of thermotolerant talcum endows the T-10 composite separator with great thermostability,whose thermal shrinkage is only 5.39%at 150°C for 0.5 h.The cell with LiFeO4cathode and the T-10 composite separator reaches 91.7 m Ah/g in discharge capacity at 4.8 m A/cm^(2)(10 C),far superior to that with pure PVDF separator(56.3 m Ah/g)and PP(51.4 m Ah/g).

Atomic structures and carrier dynamics of defects in a ZnGeP_(2) crystal

ZnGeP_(2)[ZGP] crystals have attracted tremendous attention for their applications as frequency conversion devices.Nevertheless,the existence of native point defects,including at the surface and in the bulk,lowers their laser-induced damage threshold by increasing their absorption and forming starting points of the damage,limiting their applications.Here,native point defects in a ZGP crystal are fully studied by the combination of high angle annular dark-field scanning transmission electron microscopy[HAADF-STEM] and optical measurements.The atomic structures of the native point defects of the Zn vacancy,P vacancy,and Ge-Zn antisite were directly obtained through an HAADF-STEM,and proved by photoluminescence[PL] spectra at 77 K.The carrier dynamics of these defects are further studied by ultrafast pump-probe spectroscopy,and the decay lifetimes of 180.49,346.73,and 322.82 ps are attributed to the donor V_(p)^(+)→valence band maximum[VBM] recombination,donor Ge^(+)_(Zn)→VBM recombination,and donor–acceptor pair recombination of V_(p)^(+)→V^(-)_(Zn),respectively,which further confirms the assignment of the electron transitions.The diagrams for the energy bands and excited electron dynamics are established based on these ultrahigh spatial and temporal results.Our work is helpful for understanding the interaction mechanism between a ZGP crystal and ultrafast laser,doing good to the ZGP crystal growth and device fabrication.

叔丁醇钠促进酮的选择性二氟甲基化反应

有机氟化合物广泛应用于医药、农药、新型功能材料、生命科学等领域.由于其独特的化学、物理和生物性能,近年来,发展与之相关的高效引氟方法和手段,受到了合成化学家的高度关注.相对来说,三氟甲基化反应研究较多,二氟甲基化反应发展滞后.二氟甲基作为醇羟基和硫羟基的生物电子等排体,可提高生物活性分子代谢稳定性和生物利用度,发展经济高效的选择性二氟甲基化方法对相关含氟药物的合成具有重要的意义.本研究以廉价的二氟溴乙酸乙酯为二氟卡宾来源,采用叔丁醇钠促进,在温和简单的反应条件下,实现了芳基酮的选择性二氟甲基化,表现出较高的选择性和良好的底物适用性.在该反应中,叔丁醇钠作为碱发挥了双重促进作用,在促使酮向烯醇式转变的同时,还促进二氟溴乙酸乙酯产生二氟卡宾,烯醇式中间体捕获二氟卡宾从而实现了芳基酮α位的选择性二氟甲基化.该反应底物适用性广,且方法绿色经济.

Engineering two-dimensional metal oxides and chalcogenides for enhanced electro-and photocatalysis

Two-dimensional(2D)metal oxides and chalcogenides(MOs&MCs)have been regarded as a new class of promising electro-and photocatalysts for many important chemical reactions such as hydrogen evolution reaction,CO_(2) reduction reaction and N2 reduction reaction in virtue of their outstanding physicochemical properties.However,pristine 2D MOs&MCs generally show the relatively poor catalytic performances due to the low electrical conductivity,few active sites and fast charge recombination.Therefore,considerable efforts have been devoted to engineering 2D MOs&MCs by rational structural design and chemical modification to further improve the catalytic activities.Herein,we comprehensively review the recent advances for engineering technologies of 2D MOs&MCs,which are mainly focused on the intercalation,doping,defects creation,facet design and compositing with functional materials.Meanwhile,the relationship between morphological,physicochemical,electronic,and optical properties of 2D MOs&MCs and their electro-and photocatalytic performances is also systematically discussed.Finally,we further give the prospect and challenge of the field and possible future research directions,aiming to inspire more research for achieving high-performance 2D MOs&MCs catalysts in energy storage and conversion fields.

Advanced lanthanide doped upconversion nanomaterials for lasing emission

Microlasers are narrow-band and coherent light from small cavities,which have been widely applied in biomedicine,optical interconnection,integration devices,etc.Lanthanide doped upconversion materials are potential gain media for microlasers from near infrared(NIR)to visible and UV regimes due to their multi ladder-like metastable energy levels and superior optical frequency conversion capability.The optical feedback from photon scattering of the porous upconversion nanoparticles clusters has been reported to produce upconversion random lasers.The light bouncing back and forth between two reflective surfaces or internal surface has been utilized to achieve modulated upconversion lasing emission.In addition,photon lattices and plasmonic cavities with enhanced electromagnetic fields can amplify the upconversion process within the sub-diffraction volumes and produce highly efficient upconverting lasers.In this review,the recent advances on using lanthanide doped upconversion materials for random,whispering gallery mode(WGM)/Fabry-Perot(FP)cavity and photon lattice/plasmonic cavity modulated upconversion microlasers are overviewed.Current challenges and future directions of the upconverting lasers are also discussed.

Macrophage Phenotypes and Hepatitis B Virus Infection

Globally, hepatitis B virus (HBV) infection and its related liver diseases account for 780,000 deaths every year. Outcomes of HBV infection depend on the interaction between the virus and host immune system. It is becoming increasingly apparent that Kupffer cells (KCs), the largest population of resident and monocyte-derived macrophages in the liver, contribute to HBV infection in various aspects. These cells play an important role not only in the anti-HBV immunity including virus recognition, cytokine production to directly inhibit viral replication and recruitment and activation of other immune cells involved in virus clearance but also in HBV outcome and progression, such as persistent infection and development of end-stage liver diseases. Since liver macrophages play multiple roles in HBV infection, they are directly targeted by HBV to benefit its life cycle. In the present review, we briefly outline the current advances of research of macrophages, especially the studies of their phenotypes, in chronic HBV infection.

High performance removal of sulfamethoxazole using large specific area of biochar derived from corncob xylose residue

To remove antibiotics from waste water,an alkali active porous biochar,850BC,was prepared from corncob xylose residue.In preparation,NaOH dipping was used for silicon removal and KOH activation was operated at 850℃.Further characterization containing BET,SEM,and FTIR were confirmed.850BC possessed a huge specific surface area of 3043 m^(2)·g^(−1),developed pore structure and abundant oxygen functional groups.The adsorption performance of sulfamethoxazole on 850BC was quick and efficient,and the adsorption capacity reached 1429 mg·g^(−1),which was significantly higher than other adsorbents reported previously.While pseudo-second-order kinetic model and Langmuir model could better describe the adsorption,chemisorp-tion dominated the SMX adsorption onto 850BC.In virtue of pore-filling andπ-πinteraction as major mechanism,a large surface area and rich oxygen-containing functional groups led to an excellent adsorption performance.Thus,this preparation method provided a biochar-based adsorbent with enhanced specific surface for efficient removal of antibiotic pollutants.

Electrolyte Engineering for High-Voltage Lithium Metal Batteries

High-voltage lithium metal batteries(HVLMBs)have been arguably regarded as the most prospective solution to ultrahigh-density energy storage devices beyond the reach of current technologies.Electrolyte,the only component inside the HVLMBs in contact with both aggressive cathode and Li anode,is expected to maintain stable electrode/electrolyte interfaces(EEIs)and facilitate reversible Li+transference.Unfortunately,traditional electrolytes with narrow electrochemical windows fail to compromise the catalysis of high-voltage cathodes and infamous reactivity of the Li metal anode,which serves as a major contributor to detrimental electrochemical performance fading and thus impedes their practical applications.Developing stable electrolytes is vital for the further development of HVLMBs.However,optimization principles,design strategies,and future perspectives for the electrolytes of the HVLMBs have not been summarized in detail.This review first gives a systematical overview of recent progress in the improvement of traditional electrolytes and the design of novel electrolytes for the HVLMBs.Different strategies of conventional electrolyte modification,including high concentration electrolytes and CEI and SEI formation with additives,are covered.Novel electrolytes including fluorinated,ionic-liquid,sulfone,nitrile,and solid-state electrolytes are also outlined.In addition,theoretical studies and advanced characterization methods based on the electrolytes of the HVLMBs are probed to study the internal mechanism for ultrahigh stability at an extreme potential.It also foresees future research directions and perspectives for further development of electrolytes in the HVLMBs.

光促二氟烯丙基化合物的E→Z异构化反应

有机氟化物在材料、医药以及能源等领域,有着广泛的应用前景.其中,二氟甲基(CF2)作为羰基或醚键的生物电子等排体,其引入能显著改变目标分子的生物活性。目前发展的二氟烯丙基化合物都以得到热力学稳定的反式(E)构型为主.本文建立了由易得的E-二氟烯丙基化合物异构为Z-二氟烯丙基化合物的方法.该反应由2,4,5,6-四咔唑基-1,3-苯二腈(4CzIPN)催化的光化学反应实现,反应温和、操作简便、经济性好,为Z-二氟烯丙基化合物的大量制备建立了高效方法。论文还通过克级反应和产物衍生化对当前反应的实用性进行了研究。机理研究认为,该反应经过三线态-三线态能量转移(TTET)过程完成。