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Hierarchical micro/nanostructures have garnered considerable attention for their capabilities in light modulation, but the flexible fabrication of designed optical functional structures at both micro and nano scales remains challenging. Here, a polarization‐modulated patterned laser ablation method complemented by flowing liquid is proposed to fabricate hierarchical microgrooves featuring tunable cross‐sections and engraved surface nanostructures with controllable periods and orientations. The liquid‐assisted ablation counters the shielding effect of ablation debris through laser‐induced microjets, ensuring accurate control of the microgroove's shape by modulating the laser pattern in the focal plane. Simultaneously, the absence of debris also permits the consistent formation of laser‐induced periodic surface structures (LIPSS) across the microgrooves. The LIPSS's period and orientation can be finely adjusted by manipulating the pulse energy and polarization within the patterned laser spot, facilitating the adaptable creation of hierarchical micro/nanostructures for optical application needs. As a demonstration, blazed gratings featuring orientation‐customized LIPSS are fabricated, which exhibit polarization‐dependent diffraction efficiency. The laser fabrication technique offers a highly versatile solution for sculpturing shape‐controllable hierarchical gratings on hard‐to‐machine materials, paving the way for the swift production of customized optical elements. [ABSTRACT FROM AUTHOR]

In this paper, a multi-strategy fusion enhanced Honey Badger algorithm (EHBA) is proposed to address the problem of easy convergence to local optima and difficulty in achieving fast convergence in the Honey Badger algorithm (HBA). The adoption of a dynamic opposite learning strategy broadens the search area of the population, enhances global search ability, and improves population diversity. In the honey harvesting stage of the honey badger (development), differential mutation strategies are combined, selectively introducing local quantum search strategies that enhance local search capabilities and improve population optimization accuracy, or introducing dynamic Laplacian crossover operators that can improve convergence speed, while reducing the odds of the HBA sinking into local optima. Through comparative experiments with other algorithms on the CEC2017, CEC2020, and CEC2022 test sets, and three engineering examples, EHBA has been verified to have good solving performance. From the comparative analysis of convergence graphs, box plots, and algorithm performance tests, it can be seen that compared with the other eight algorithms, EHBA has better results, significantly improving its optimization ability and convergence speed, and has good application prospects in the field of optimization problems. [ABSTRACT FROM AUTHOR]

Fabricating precision microgrooves with controllable cross‐sections on difficult‐to‐machine materials is significantly valuable but still challenging. Herein, a patterned laser‐induced microjet‐assisted ablation method for cross‐sectional profiles controllable laser micromachining is proposed. During the liquid‐assisted laser ablation process, debris and bubbles that may disturb the laser energy deposition can be instantaneously expelled by a directional laser‐induced microjet. The Gaussian laser spot is spatially modulated into specific geometric shapes, such as triangles, to tune locally deposited laser energy to carve microgrooves with designed cross‐sections. To achieve customized microgrooves efficiently, a reliable geometrical model based on the ablation threshold theory is developed to guide the processing parameter selection, including the laser spot shape, polarization, pulse energy, and scanning strategies. The simulation and experimental results confirm that this method achieves the decoupled control of the groove depth and width in a single‐path laser ablation process. Using this method, the design and manufacturing of microgrooves with controllable cross‐sections on single crystalline silicon carbide are demonstrated. The patterned laser‐induced microjet‐assisted ablation method provides a new route for fabricating precision microgrooves with controllable cross‐sections on difficult‐to‐machine materials. [ABSTRACT FROM AUTHOR]

Process of “high temperature carbonization and low temperature chlorination”, which was considered to be one of the most promising technologies, could extracte more than 70% titanium from the furnace slag containing TiO2 10% - 30%. TiC-containing slag was the product of high temperature carbonization, and to meet the requirement of the following chlorination process, it needs to be crushed and grounded to a suitable size distribution. The air jet pulverization of TiC-containing slag was studied in this paper. On the one hand, By CFD numerical simulation, the distribution regularity of nozzle flow field about the main crushing equipment was obtained with different throat diameters and crushing gas pressures. On the other hand, the influences of nozzle throat diameter, crushing pressure, and collision angles on the particle size of the powder were studied by experiment. With the better parameters, the particle size distribution of the product powder was uniform.

Subwavelength‐structured metasurfaces working in visible and near‐infrared bands present a high challenge in large‐scale device fabrication. In this study, a scalable, high‐efficient, and low‐cost laser‐induced nanopatterning technique is exploited to fabricate a kind of short‐range disordered metagratings, which enables broadband polarization‐independent absorption in the visible to near‐infrared wavelength. The short‐range disorder of the laser‐induced nanogratings originates from the laser‐induced thermal effect and can be spontaneously organized during laser nanopatterning. The unique disorder can break the unidirectional characteristics of the nanogratings, which empowers the metagratings to excite coupled resonance modes. This helps to achieve near‐perfect absorption in the visible to near‐infrared band (400–1100 nm) with an excellent angular tolerance (up to 60°) and average absorptivities of 96.3% and 93.5% under the TM and TE modes, respectively. These low‐cost metagratings can potentially inspire wide applications in the fields of solar cells, sensing, and thermal emitters. [ABSTRACT FROM AUTHOR]

Hierarchical metal grids are proven to be a promising solution for achieving high‐performance flexible transparent electrodes (FTEs) due to their significantly enhanced conductivity without noticeably sacrificing transparency. This work develops a one‐step mask‐free line‐shaped laser lithography by separated pulse laser ablation to efficiently fabricate large‐area FTEs composed of hierarchical metal grids, namely microscale grids interconnected with aligned nanowire arrays. The linewidth of aligned wires is highly controllable from the nanometer scale far beyond the diffraction limit (<λ/10) to the micrometer scale. This work experimentally studies the overall performance of FTEs to provide a guideline for selecting the layout and feature sizes of hierarchical metal grids. Hierarchical metal grids with 50 nm nanowires aligned inside the microscale grids show outstanding optoelectronic properties and mechanical stability, with sheet resistance of 4.6 Ω sq−1, transmittance of 82.9%, and a tiny increase in sheet resistance less than 4% after 1000 cycles of bending tests. These results prove that the line‐shaped laser lithography technique is a facile, low‐cost, and high‐throughput fabrication method for high‐performance FTEs. [ABSTRACT FROM AUTHOR]

Fuzzy front-end (FFE) innovation is the important initial phase of manufacturing companies' new product development (NPD) process, which can be a factor that determines manufacturers' NPD performance and sustainable growth. This study seeks to investigate the role of FFE vertical external involvement (FFE customer involvement and FFE supplier involvement) in advancing firms' corporate social responsibility (CSR) and NPD performance in the COVID-19-influenced age of volatility, uncertainty, complexity and ambiguity (VUCA). This study adopts an organizational learning (OL) perspective as its theoretical foundation in constructing a comprehensive framework by developing a series of hypotheses. In addition, we test the mediating effect of CSR on the relationship between FFE vertical external involvement and firm NPD performance. We use the structural equation modeling method to examine our hypotheses empirically based on data collected from 548 Chinese manufacturing companies. The findings illustrate that FFE customer involvement and FFE supplier involvement are vital drivers of a firm's CSR engagement. Furthermore, we find that FFE supplier involvement plays a more significant role than FFE customer involvement in contributing to NPD performance. Finally, we find that a firm's CSR engagement positively mediates the relationship between FFE vertical external involvement and NPD performance. [ABSTRACT FROM AUTHOR]

Large‐scale nanopatterning at low cost and high throughput is crucial to the practical applications of metasurfaces. Phase‐change materials equipped in these metasurfaces as modulation layers or resonators are generally applied to achieve a tunable function and have attracted significant attention. Here, an efficient method is developed by combining ultrafast laser localized modification/ablation and subsequent etching to fabricate nanostructures on a phase‐change material, Ge2Sb2Te5 (GST), over a wafer‐sized area. The localized laser treatments under gradually increased laser fluences contribute to the variety of achievable nanostructures including disk and ring structures, whose feature sizes and periods can be tuned by adjusting laser parameters and subsequent etching conditions. A mid‐infrared metasurface absorber is designed and fabricated by using the GST ring units as resonators. Notably, varying the geometrical features of rings allows generating dual‐band and tri‐band absorption peaks in the mid‐infrared spectral range, whose peak absorptivity can reach ≈92%. By converting GST from amorphous to crystalline state, a broad absorption spectral redshift of 700 nm is achieved. The large‐area high‐throughput fabrication together with high‐absorption design demonstrates their potential in mass production of phase‐change metasurface‐based absorbers. [ABSTRACT FROM AUTHOR]

Metallic nanowires have exhibited paramount importance in achieving functional electrical, electrochemical, and optical performances due to their unique physicochemical properties. Efficient fabrication of the nanowires with controllable geometry and line width is highly required in related applications. Here a new far‐field laser parallel direct writing approach for fabricating nanowire array far beyond the diffraction limit by a modulated vector beam with dual‐peak intensity distribution is reported. Such a modulated beam can perform selective laser ablation to fabricate nanowires, whose line width can be largely reduced by tuning the dual‐peak orientation relative to the laser scanning direction. As a demonstration, a 157 nm‐wide (less than λ/3) gold nanowire, reaching ≈1/20 of the diffraction limit, has been fabricated in far field by using a low numerical aperture microscope objective (NA = 0.1). The nanowire fabrication efficiency is also largely improved by applying multifocal modulated vector beams for parallel processing. [ABSTRACT FROM AUTHOR]

Laser‐induced periodic surface structures (LIPSS) have become an important avenue towards surface nanopatterning and certain device applications due to their subwavelength feature size and versatility with different materials. However, the uncontrollable non‐uniformity in achievable nanostructures presents a limit towards its practical application. Here, a robust approach is proposed to obtain controllable nanostructures with long‐range order based on a new insight into one of the electromagnetic origins of nonuniformity of LIPSS, namely a half‐periodic mismatched optical enhancement (h‐MOE) effect. The h‐MOE effect originates from the interference enhancement of surface plasmon polaritons (SPPs) located between tips of every two adjacent ripples in laser scanning process. It is found that LIPSS can be self‐aligned and highly controllable if the h‐MOE effect is elaborately modulated through designed laser scanning strategies especially sequential scanning paths. The new laser nanopatterning approach based on h‐MOE demonstrates controllable patterning ability to theoretically infinitely large‐area super‐straight gratings, orientation‐controllable gratings, and half‐periodic mismatched nanohole arrays. [ABSTRACT FROM AUTHOR]

The electrospinning electric field is the main factor responsible for the jet stretching force. Previous studies showed that nonhomogeneous electric field would affect the jets formed during the multi-needles electrospinning. Therefore, a multitude of methods were explored to optimize the electric field in multi-needles electrospinning, such as adjusting the supplied voltage on each needle, varying the space of the needles and spatial distribution of the needles. In this paper, three categories of needles distribution were explored for a homogeneous electric field and the design of a higher needles density of electrospinning head. The theoretical and experimental results showed that the homogeneous electric field formed with the trapezoidal head at 15mm distance while the others’ head required over 30mm. Hence, the trapezoidal arrangement is a better multi-needles distribution for electrospinning head, and has much more significance for high yield of electrospinning nanofibers. [ABSTRACT FROM AUTHOR]

• Efficiently fabricating hierarchical nanotextured microgrooves through hybrid laser processing. • Producing uniform 1D nanogratings and 2D nanoholes on V-shaped microgrooves. • Laser interference and laser-SPPs interference contribute to the formation of those nanostructures. • Those nanostructures can engrave into many microgrooves within one scanning process. Functional surfaces with hierarchical micro-/nanostructures play a vital role in improving performances in emerging fields over the past decades. In this work, we propose a hybrid manufacturing method for efficiently fabricating hierarchical nanotextured microgrooves by combining fly cutting and femtosecond laser nanopatterning. Nanostructures, including nanogratings and nanoholes, can be uniformly generated in a V-shaped groove by controlling laser polarization. We experimentally study the influence of the laser parameters (laser fluence and effective pulse number) to investigate the morphological evolution of nanostructures in the V-shaped groove under laser irradiation. By theoretical calculations and analyses, we find that the interference between the incident and reflected laser is helpful for ablating the nanogratings. In addition, this interference can also couple with the laser-SPPs (surface plasmon polaritons) interference and form nanoholes. The results enrich the diversity of achievable laser-induced periodic surface structures on complex surfaces and provide a new way to efficiently fabricate large-area hierarchical micro-/nanostructures at low cost. [ABSTRACT FROM AUTHOR]

It is important to improve the forecasting performance of rainfall-runoff models due to the high complexity of basin response and frequent data limitations. Recently, many studies have been carried out based on deep learning and have achieved significant performance improvements. However, their intrinsic characteristics remain unclear and have not been explored. In this paper, we pioneered the exploitation of short lag-times in rainfall-runoff modeling and measured its influence on model performance. The proposed model, long short-term memory with attentive long and short lag-time (LSTM-ALSL), simultaneously and explicitly uses new data structures, i.e., long and short lag-times, to enhance rainfall-runoff forecasting accuracy by jointly extracting better features. In addition, self-attention is employed to model the temporal dependencies within long and short lag-times to further enhance the model performance. The results indicate that LSTM-ALSL yielded superior performance at four mesoscale stations (1846~9208 km2) with humid climates (aridity index 0.77~1.16) in the U.S.A., for both peak flow and base flow, with respect to state-of-the-art counterparts. [ABSTRACT FROM AUTHOR]