Flexible, Transparent and Conductive Metal Mesh Films with Ultra‑High FoM for Stretchable Heating and Electromagnetic Interference Shielding

Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference(EMI)shielding,achieving a flexible EMI shielding film,while maintaining a high transmittance remains a significant challenge.Herein,a flexible,transparent,and conductive copper(Cu)metal mesh film for EMI shielding is fabricated by self-forming crackle template method and electroplating technique.The Cu mesh film shows an ultra-low sheet resistance(0.18Ω□^(-1)),high transmittance(85.8%@550 nm),and ultra-high figure of merit(>13,000).It also has satisfactory stretchability and mechanical stability,with a resistance increases of only 1.3%after 1,000 bending cycles.As a stretchable heater(ε>30%),the saturation temperature of the film can reach over 110°C within 60 s at 1.00 V applied voltage.Moreover,the metal mesh film exhibits outstanding average EMI shielding effectiveness of 40.4 dB in the X-band at the thickness of 2.5μm.As a demonstration,it is used as a transparent window for shielding the wireless communication electromagnetic waves.Therefore,the flexible and transparent conductive Cu mesh film proposed in this work provides a promising candidate for the next-generation EMI shielding applications.

Paleoenvironment of marine-continental transitional shales in the lower Permian Shanxi formation,southeastern Ordos Basin,China

The paleoenvironment of shales can be reconstructed to some extent using the combinations or concentrations of elements that correlate strongly with environmental conditions.In this study,we analyzed rare earth elements(REEs),major elements,and trace elements in the marine-continental transitional shales(transitional shales for short)of the Shan 2^(3)submember of the Shanxi Formation in the southeastern Ordos Basin.The purpose is to deduce the paleoenvironmental conditions of the shales,encompassing paleoredox,paleoclimate,paleoproductivity,and paleo-provenance.The Shan 2^(3)submember comprises four sections,namely Shan 2^(3)-1,Shan 2^(3)-2,Shan 2^(3)-3,and Shan 2^(3)-4.The Ba/Al,P/Al,and Cu/Al ratios,along with biogenic barium(Babio),indicate that the paleoproductivity of the submember peaked during the Shan 2^(3)-1 deposition and exhibited a downtrend upward in other sections.Trends in the Uau and the Ni/Co,V/Cr,U/Th,and V/Sc ratios suggest that suboxic conditions prevailed during the Shan 2^(3)-1 deposition,with the oxidation level gradually increasing from Shan 2^(3)-1 to Shan 2^(3)-4.C-value and the Sr/Cu vs.Ga/Rb cross-plot indicate a warm and arid paleoclimate during the Shan 2^(3)-1 deposition,which transitioned to cooler,drier conditions during the deposition of other sections.Indicators sensitive to paleoclimate,such as the K/Rb and Th/U ratios,along with the ICV,PIA,and Chemical Index of Alteration(CIA),highlight elevated weathering from Shan 2^(3)-2 to Shan 2^(3)-4,with Shan 2^(3)-1 exhibiting the weakest weathering during its deposition.As suggested by the REE data,the Zr/Sc vs.Th/Sr cross-plot,provenance discriminant functions,and the cross-plots of Hf vs.La/Th,Th vs.Hf-Co,and∑REE vs.La/Yb,the sedimentary provenance for the transitional shales of the Shan 2^(3)submember is of multiple origins,with significant contributions from the Upper Continental Crust(UCC).Discriminant diagrams,including those of Th-Co-Zr/10,Th-Sc-Zr/10,La-Th-Sc,and K_(2)O/Na_(2)O vs.SiO_(2),suggest that the transitional shales of the Shan 2^(3)submember were primarily deposited under tectonic settings such as continental island arcs(CIAs)and passive continental margins(PCMs).

Experimental Study on the Axial Compression Behavior of Short Columns of Steel-Fiber-Reinforced Recycled Aggregate Concrete

In order to study the axial compression performances of short columns made of recycled aggregate concrete,four samples were designed with different recycled aggregate replacement rates and carbon fibre reinforced plastics(CFRP)sheets.Then,monotonic loading was implemented to assess the variation trends of their axial compression properties.The ABAQUS finite element software was also used to determined the compression performances.Good agreement between experimental and numerical results has been found for the different parameters being considered.As shown by the results,recycled coarse aggregates result in improved ductility and better deformation performance of the specimens.The failure of specimens caused by pre damage can be compensated by using CFRP sheets,by which both the resistance to deformation and the axial carrying capacity of columns can be increased.

中国碳中和技术发展路径

Carbon neutrality has been considered a new focus of countries for achieving the goal of the Paris Agreement.China has pledged to peak CO_(2) emissions before 2030 and achieve carbon neutrality before 2060,and a"1+N"policy framework has been built to guide the implementations.Scientific and technological innovation has been emphasized as one of the key strategies to establish an innovation system,strengthen research,and promote applications of green and low-carbon technologies[1].Despite numerous studies and policies on decarbonization technologies,studies focusing on technological development pathways for China’s carbon neutrality are needed[2].

Patternable and transferable silver nanowire conductors via plasma-enhanced cryo-transferring process towards highly stretchable and transparent capacitive touch sensor array

Stretchable transparent electrode(STE)plays a key role in numerous emerging applications as an indispensable component for future stretchable devices.The embedded STE,as a promising candidate,possesses balanced performances and facile preparation procedures.However,it still suffers from the defects of conductive materials caused by the transferring,which results in the irreversible failure of devices.In this work,a patternable silver nanowire(AgNW)STE was fabricated by a plasma-enhanced cryo-transferring(PEC-transferring)process.Owing to the plasma-induced sintering,the AgNW network obtained remarkable improvement in robustness,which ensured the intact network after transferring and thus led to superior tensile electrical properties of the STE.Furthermore,serpentine patterns were utilized to optimize the tensile electrical properties of the STE,which achieved a figure of merit of 292.8 and 150%resistance changing under 50%strain.As a practical application,a 4×3 array of the mutual-capacitive type stretchable touch sensors was demonstrated for future touch sensors in stretchable devices.The PEC-transferring process opened a new avenue for patternable embedded STEs and exhibited its high potential in wearable electronics and the Internet of Thing devices.

Self-powered electronic paper with energy supplies and information inputs solely from mechanical motions

The electronic paper(E-paper)displays features such as flexibility,sunlight visibility,and low power consumption,which makes it ideal for Internet of Things(IoT)applications where the goal is to eliminate bulky power modules.Here,we report a unique self-powered E-paper(SPEP),where information inputs and energy supplies are all converted from mechanical motion by a triboelectric nanogenerator(TENG).The operation of an electrophoretic E-paper is first investigated,identifying the current density as a determinative parameter for driving pigment particle motion and color change.Electrical and optical responses of the E-paper driven by a slidingmode TENG are then found to be consistent with that under a current source mode.All-in-one monochromic and chromatic SPEPs integrated with a flexible transparent TENG are finally demonstrated,and a pixelated SPEP is discussed for future research.The sliding-driven mechanism of SPEP allows for a potential handwriting function,is free of an extra power supply,and promises undoubtedly a wide range of future applications.