Nonconjugated clusteroluminogens(CLgens),such as proteins and polystyrene,have become increasingly important in *** show many advantages over traditional conjugated dyes with fused aromatic rings in biological ***,CLg...
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Nonconjugated clusteroluminogens(CLgens),such as proteins and polystyrene,have become increasingly important in *** show many advantages over traditional conjugated dyes with fused aromatic rings in biological ***,CLgens have historically been unheeded because of their weak visible emissions in the aggregate state,namely clusteroluminescence(CL).Changing the electronic structures of CLgens by precisely regulating the intramolecular throughspace interaction(TSI)to improve their photophysical properties remains an enormous ***,we propose a general strategy to construct a higher-level intramolecular TSI,namely secondary TSI constructed by the primary TSI and a TSI linker,in multi-aryl-substituted alkanes(MAAs).By introducing methyl and phenyl into 1,1,3,3-tetraphenylpropane,the modified MAAs show efficient CL with high luminescence quantum yield(-40%)and long emission wavelength(-530 nm).Then,comprehensive experiments and theoretical studies demonstrate that molecular rigidity and overlap of subunits play pivotal roles in improving these hierarchical *** work not only provides a feasible strategy to achieve controllable manipulation of hierarchical TSIs and CL but also establishes comprehensive TSI-based aggregate photophysics.
We report Ge23Sb7S70 chalcogenide ring resonators with up to 8 × 104 quality factors operating around 3.6 µm wavelength fabricated through e-beam lithography. Their rib waveguide geometry can be engineered t...
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The demand for sustainable, high-performance materials has led to increased interest in bio-based composites. However, optimizing the mechanical properties of such materials for engineering applications remains a chal...
The demand for sustainable, high-performance materials has led to increased interest in bio-based composites. However, optimizing the mechanical properties of such materials for engineering applications remains a challenge. This study addresses this gap by developing and characterizing an epoxy-based biocomposite reinforced with sugarcane bagasse particles, focusing on the influence of cyclic thermal treatment on its properties. The bagasse particles were chemically treated with 1 M NaOH to remove impurities, improve interfacial bonding with the epoxy matrix, and enhance the overall composite performance. The treated particles j were pulverized to 470 µm and incorporated into the epoxy matrix (0–20 wt%) using the hand layup method. The composites were divided into untreated and thermally treated groups, with the latter subjected to cyclic thermal treatment (100 °C for 3 h over 7 days). Mechanical, wear, and water absorption properties were evaluated, while fractured surface morphologies were analyzed using SEM. Results revealed that cyclic thermal treatment significantly enhanced the composites’ performance, with the 15 wt% heat-treated composite showing optimal properties: density of 1.102 g/cm3, flexural strength of 29.13 MPa, ultimate tensile strength of 103.50 MPa, impact strength of 3.49 kJ/m2, hardness of 64.70 HS, and wear indices of 0.034 mg. These findings demonstrate that alkali treatment and cyclic thermal treatment synergistically enhance the performance of bio-composites, making them suitable for diverse applications, including automotive, aerospace, and other engineering fields.
In this paper, we have presented our experiment results including (a) use a slowly thermal spray process deposition an yttrium oxide (Y2O3) film with thickness of $200\ \mu\mathrm{m}$ on the aluminum alloy (AA6061). T...
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The future deployment of terawatt-scale proton exchange membrane water electrolyzer (PEMWE) technology necessitates development of an efficient oxygen evolution catalyst with low cost and long lifetime. Currently, the...
The future deployment of terawatt-scale proton exchange membrane water electrolyzer (PEMWE) technology necessitates development of an efficient oxygen evolution catalyst with low cost and long lifetime. Currently, the stability of the most active iridium (Ir) catalysts is impaired by dissolution, redeposition, detachment, and agglomeration of Ir species. Here we present a ripening-induced embedding strategy that securely embeds the Ir catalyst in a cerium oxide support. Cryogenic electron tomography and all-atom kinetic Monte Carlo simulations reveal that synchronizing the growth rate of the support with the nucleation rate of Ir, regulated by sonication, is pivotal for successful synthesis. A PEMWE using this catalyst achieves a cell voltage of 1.72 volts at a current density of 3 amperes per square centimeter with an Ir loading of just 0.3 milligrams per square centimeter and a voltage degradation rate of 1.33 microvolts per hour, as demonstrated by a 6000-hour accelerated aging test.
Highly ordered Tb_(x)Fe_(7)Co_(3)(x=0,0.6,0.8)nanowires were synthesized in alumina templates by electrochemical deposition ***,the effects of Tb content and annealing treatment on the phase composition,morphology,cry...
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Highly ordered Tb_(x)Fe_(7)Co_(3)(x=0,0.6,0.8)nanowires were synthesized in alumina templates by electrochemical deposition ***,the effects of Tb content and annealing treatment on the phase composition,morphology,crystalline structure and magnetic properties were *** asdeposited Tb_0 Fe_(7)Co_(3)nanowires comprise Fe_(7)Co_(3)*** after adding Tb,the diffraction peaks slightly shift left,indicating the infiltration of Tb atoms into Fe_(7)Co_(3)*** annealing,Tb_0 Fe_(7)Co_(3)nanowires still consist of Fe_(7)Co_(3)phase with a slight enhancement on *** the annealed nanowires with Tb doped present a complex phase composition containing Fe3 Tb,Fe_(2)Tb,Co_(3)Tb,Co_(17)Tb_(2),TbFeO_(3)and Fe_(2)O_(3)phases distribute in the central portion,and Co_(0.72)Fe_(0.28)at the nanowire outer *** annealed Tb_(x)Fe_(7)Co_(3)(x=0.6,0.8)nanowires show higher magnetic performance owing to the formation of hard magnetic phases,the interfacial elastic coupling between hard and soft phases and the coherent Fe3 Tb/Co_(3)Tb interface which restrain the domain wall *** be specific,the coercivity and remanence ratio of TbxFe_(7)Co_(3)(x=0.6,0.8)nanowires significantly enhance with increasing Tb content.
Dendrimers,as the latest generation of artificial macromolecules,have aroused great attention in the field of clusteroluminescence owing to their unique structural and photophysical ***,previously reported dendrimers ...
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Dendrimers,as the latest generation of artificial macromolecules,have aroused great attention in the field of clusteroluminescence owing to their unique structural and photophysical ***,previously reported dendrimers with clusteroluminescenence property usually containπelectrons-involved carbonyl groups and/or environment-sensitive aliphatic amine moieties in their structures,thus complicating the interpretation of the emission *** the other hand,a systematic investigation on the luminescence performance of dendrimers with diverse generations is significantly important for the researchers to gain further mechanistic insights into the clusteroluminescence,but has still been scarcely *** this contribution,we reported a series of oxygen and sulfur-based pure n-electron dendrimers with different generations from G1 to *** from the highly-branched three-dimensional crowded molecular structures,all these dendrimers exhibited bright fluorescence emission in visible light region due to their prominent clusteroluminescence ***,the fluorescence intensity and emission wavelength were simultaneously boosted as their generation increased due to the more crowded molecular architectures,as well as the formation of tighter and larger clusters at higher ***,these dendrimers also showed concentration-and aggregation-enhanced luminescence behaviors,presenting typical aggregation-induced emission(AIE)*** with remarkable water solubility and biocompatibility as well as the excellent photostability,the G3 dendrimer selected as a representative was successfully applied in the multicolor cell *** addition,the G3 dendrimer was also proved to be capable of acting as a molecular ruler to detect specific-sized molecule in aqueous *** work not only validated the rationality of the clusteroluminescence mechanism but also offered high-performance clusteroluminogens for practical application.
Developing on-chip functional devices requires reliable fabrication methods with high resolution for miniaturization,desired components for enhanced performance,and high throughput for fast prototyping and mass ***,la...
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Developing on-chip functional devices requires reliable fabrication methods with high resolution for miniaturization,desired components for enhanced performance,and high throughput for fast prototyping and mass ***,laser-based bubble-pen lithography(BPL)has been developed to enable sub-micron linewidths,in situ synthesis of custom materials,and on-demand patterning for various functional components and *** exploits Marangoni convection induced by a laser-controlled microbubble to attract,accumulate,and immobilize particles,ions,and molecules onto different *** years have witnessed tremendous progress in theory,engineering,and application of BPL,which motivated us to write this ***,an overview of experimental demonstrations and theoretical understandings of BPL is ***,we discuss the advantages of BPL and its diverse applications in quantum dot displays,biological and chemical sensing,clinical diagnosis,nanoalloy synthesis,and *** conclude this review with our perspective on the challenges and future directions of BPL.
Microplastics are a growing environmental concern, with a large body of evidence documenting substantial distribution of plastic material in virtually all environmental compartments. Countermeasures that help to bind,...
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Microplastics are a growing environmental concern, with a large body of evidence documenting substantial distribution of plastic material in virtually all environmental compartments. Countermeasures that help to bind, aggregate, or coalesce these distributed particles might result in lower human and animal exposures. Pressure sensitive adhesives (PSAs) have been identified as a viable microplastic (MP) capture mechanism with a range of potential use conditions. As with any countermeasure, there is a need to evaluate potential solutions in terms of collection efficiency, cost, ease of installation, etc. Expanding on our previous work, spray-coated PSAs were investigated as submerged surfaces as tools to assess MP binding in aqueous dispersions. Resins containing two differing molecular weights of poly(2-ethylhexyl acrylate) PSA (92k and 950k), and a 50:50 by weight mixture of the two resins were applied as spray-coated substrates to compare the effect of resin composition on MP-adhesive binding. Thin films of PSA (92k 6 ± 1 μm, 950k 4 ± 2 μm, 50:50 BD 6.5 ± 1 μm) were sprayed on borosilicate glass slides using a commercial air brush. Polydisperse nylon-12 particles varying in size from 15-30 µm in diameter were dispersed in deionized water at concentrations between 0.01 and 5 mg mL -1 and agitated under ambient conditions to assess adhesive binding as quantitative comparisons of microparticle capture. Mixed assays were also performed comparing binding of common MP species including polyethylene (50, 200 µm), polystyrene (10 µm), and polyester fibers (1000 µm) to understand how varying composition, size, and form factor affect adsorption. The glass slide method showed increasing linear trends of particle binding with increased adhesive exposure time and MP concentration. The lower molecular weight 92K adhesive had lower viscosity, higher wettability for microplastics but also led to a less stable adhesive film complicating analysis. As a field-deployable scheme for mi
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