摘要：Ceramic dielectric materials with high dielectric strength and mechanisms of their internal factors affecting dielectric strength are significantly valuable for industrial application,especially for selection of suitable dielectric materials for high-power microwave transmission devices and reliable power *** magnesium oxide(MgO),a kind of ceramic dielectric material,possesses great application potential in high-power microwave transmission devices due to its high theoretical dielectric strength,low dielectric constant,and low dielectric loss properties,but its application is limited by high sintering temperature during *** work presented the preparation of a new type of multiphase ceramics based on MgO,which was MgO-1%ZrO_(2)-1%CaCO_(3-x)%MnCO_(3)(MZCM_(x),x=0,0.25,0.50,1.00,1.50,in molar),and their phase structures,morphological features,and dielectric properties were *** was found that inclusion of ZrO_(2) and CaCO_(3) effectively inhibited excessive growth of MgO grains by formation of second phase,while addition of MnCO_(3) promoted the grain boundary diffusion process during the sintering process and reduced activation energy for the grain growth,resulting in a lower ceramic sintering *** performance,including high dielectric strength(Eb=92.3 kV/mm)and quality factor(Q×f=216642 GHz),simultaneously accompanying low dielectric loss(<0.03%),low temperature coefficient of dielectric constant(20.3×10^(–6)℃^(–1),85℃)and resonance frequency(–12.54×10^(–6)℃^(–1)),was achieved in MZCM1.00 ceramics under a relatively low sintering temperature of 1350℃.This work offers an effective solution for selecting dielectric materials for high-power microwave transmission devices.

摘要：The development of smart bioelectronics and biomedical devices has significantly advanced the field of biomedical engineering,enabling a myriad of applications from basic biomedical research to clinical medicine and *** at the intersection of materials science,mechanical,electrical,and bioengineering,this fascinating field has attracted considerable attention from researchers all over the world,providing new healthcare solutions which were impossible *** brain–machine interface to biomedical nano/micro-robots,different materials and manufacturing methodologies have been developed to advance the functionalities of the bioelectronic systems to meet the ever-increasing demand of biological and bioinspired applications(Fig.1).

摘要：Extracellular vesicles(EVs)are lipid-bound vesicles secreted by cells into the extracellular *** are three types of EVs,including exosomes(30–150 nm)[1],microvesicles(100–1000 nm),and apoptotic bodies(50–4000 nm).EVs are also important intercellular communication carriers in many physiological and pathological processes such as immune response,tumor invasion,and metastasis[2,3].EVs circulate in various body fluids(e.g.,peripheral blood and urine),while carrying genetic information(e.g.,proteins and nucleic acids)from the parent cells[2,4,5].Thus,their source can be identified through gene analysis[6–10].

摘要：Main observation and conclusion Amicetin and congeners constitute a small family of complex pyrimidine nucleosides,which exhibit strong antibiotic activities against Gram-positive bacteria and notably against strains of Mycobacterium ***,we report chemical synthesis of a series of disaccharide congeners of the amicetin family,including amicetin,plicacetin,and cytosaminomycin A—*** is the first time for successful synthesis of amicetin,the prototypical member,and *** synthetic approach employs glycosyl N-phenyltrifluoroacetimidate and thioglycoside donors to construct the characteristic aminodeoxydisaccharides consisting ofα-(1→4)-glycosidic linkage,uses gold(I)-catalyzed N-glycosylation to furnish 2-deoxy-β-nucleosides,and finally exploits amidation and global deprotection to complete the *** is noteworthy that the 3-O-protecting group in the 2-deoxydisaccharide donors is found to be crucial for a successful N-glycosylation to assemble the cytosaminomycin disaccharide nucleosides.

摘要：The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial *** identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary *** methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally *** microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant *** this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 *** harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion *** further demonstrate the employment of the microfluidic chip for the AST of *** to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and *** determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate *** proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens.

摘要：Chiral phosphorus ligands have played a crucial role for the recent advances in asymmetric *** review summarizes chiral phosphorus ligands developed from the Laboratory of Professor Xumu Zhang in the latest 25 years.A number of iconic phosphorus ligands including bisphosphorus ligands with rigid chiral backbone such as BICP,PennPhos,TunePhos,and f-Binaphane,P-chiral bisphosphorus ligands TangPhos,Binapine,and DuanPhos,phosphine-phosphoramidte ligand YanPhos,noncovalent interaction-assisted ferrocenyl phosphorus ligand ZhaoPhos and WudaPhos,and tridentate ferrocenyl phosphorus ligands f-amphox are introduced,and their applications in asymmetric hydrogenation are emphasized.

摘要：In the realm of near-infrared spectroscopy,the detection of molecules has been achieved using on-chip waveguides and *** the mid-infrared band,the integration and sensitivity of chemical sensing chips are often constrained by the reliance on off-chip light sources and *** this study,we demonstrate an InAs/GaAsSb superlattice mid-infrared waveguide integrated *** GaAsSb waveguide layer and the InAs/GaAsSb superlattice absorbing layer are connected through evanescent coupling,facilitating efficient and highquality detection of mid-infrared light with minimal *** conducted a simulation to analyze the photoelectric characteristics of the ***,we investigated the factors that affect the integration of the InAs/GaAs⁃Sb superlattice photodetector and the GaAsSb *** thicknesses and lengths for the absorption lay⁃er are *** the absorption layer has a thickness of 0.3μm and a length of 50μm,the noise equiva⁃lent power reaches its minimum value,and the quantum efficiency can achieve a value of 68.9%.The utilization of waveguide detectors constructed with Ⅲ-Ⅴ materials offers a more convenient means of integrating mid-infra⁃red light sources and achieving photoelectric detection chips.

摘要：The nanoscale core/shell heterostructure is a particularly efficient motif to combine the promising properties of plasmonic materials and rare-earth compounds; however, there remain significant challenges in the synthetic control due to the large interfacial energy between these two intrinsically unmatched materials. Herein, we report a synthetic route to grow rare-earth-vanadate shells on gold nanorod （AuNR） cores. After modifying the AuNR surface with oleate through a surfactant exchange, well-packaged rare-earth oxide （e.g., Gd2O3：Eu） shells are grown on AuNRs as a result of the multiple roles of oleate. Furthermore, the composition of the shell has been altered from oxide to vanadate （GdVO4：Eu） using an anion exchange method. Owing to the carefully designed strategy, the AuNR cores maintain the morphology during the synthesis process; thus, the final Au/GdVO4： Eu core/shell NRs exhibit strong absorption bands and high photothermal efficiency. In addition, the Au/GdVO4：Eu NRs exhibit bright Eu^3＋ fluorescence with quantum yield as high as -17%; bright Sm^3＋ and Dy^3＋ fluorescence can also be obtained by changing the lanthanide doping in the oxide formation. Owing to the attractive integration of the plasmonic and fluorescence properties, such core/shell heterostructures will find particular applications in a wide array of areas, from biomedicine to energy.

摘要：Under the background of increasing energy crisis and global warming,semiconductor-based photocatalysis has received tremendous attention due to its potential application in green energy production,CO_(2) reduction and pollutant *** photocatalytic activity of semiconductors,however,remains low due to issues like fast recombination of photo-generated electron-hole pairs,limited electron mobility,restricted optical absorption or insufficient active *** appropriate heterojunctions is proved to be a promising method to address most of these issues and thus to improve the photocatalytic *** this review,the working mechanism of various heterojunctions is presented *** most recent advances of strategies in designing and preparing efficient heterojunction photocatalysts are further summarized and some perspectives on the future directions in this field are provided.

摘要：The design and preparation of non-precious metal and carbon-based nanocomposites are critical to the development of efficient catalysts for technologies ranging from water splitting to fuel cell. Here, we present a constrained-volume self-assembly process for the one-step continuous precipitation-induced formation of soft colloidal particles, in which hydrophobic organoferrous compound,（Ph3P）2Fe（CO）3, is encapsulated within poly（styrene-co-acrylonitrile） nanoparticles（NPs）. The protective and confining polymer matrix ensures uniform carbonization and dispersion of（Ph3P）2Fe（CO）3 within a carbon matrix after a pyrolysis process. The obtained carbon NPs are successfully co-doped with Fe, P and N with a relatively high surface area of-380 m^2 g^（-1）. The Fe-P-N-doped carbon catalyst exhibits high catalytic performance and stability toward oxygen reduction reaction in both alkaline and acidic electrolytes via a favorable four-electron pathway. Meanwhile, the catalytic capability of Fe-P-N-doped carbon can be tailored by the tunable nanostructures.