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Submerged pulsating air jet polishing (SPAJP) is a recently developed sub-aperture energy beam polishing process. This paper investigates the potential application of SPAJP on brittle substrates for deterministic maskless surface structuring. Initially, experimental studies were conducted using monocrystalline silicon wafers as the processing substrate to characterize the polishing removal characteristics of SPAJP and identify an optimal process parameter combination for efficient surface preparation. To achieve processing determinacy, the generalized Gaussian distribution (GGD) was employed to accurately model SPAJP footprints. Additionally, an improved feedrate scheduling model was derived for GGD-modeled footprints to facilitate deterministic structured processing by SPAJP. Finally, the feasibility of the proposed deterministic approach to maskless surface structuring using SPAJP is validated through simulation analysis and microstructure fabrication tests, which include the fabrication of line and ruled microstructures. The results showcase high consistency between simulated and experimental profiles, highlighting the precision and controllability of SPAJP in maskless surface structuring. This research significantly contributes to advancing surface form generation and microstructure processing with high certainty.

Moving boundaries of electrical double layers have shown promising capability in driving directional electron flows in solids, leading to a range of hydrovoltaic effects. The recent discovery of a photohydrovoltaic phenomenon utilizes a moving illumination zone to generate moving boundaries with different properties at the solid–water interface, referred to as the kinetic photovoltaic effect. Here, oxygen was found to act as a chemical switch to turn on and off the kinetic photovoltaic effect. Introducing oxygen would rapidly diminish the kinetic photovoltage in p-Si. On the contrary, degassing oxygen leads to a gradual recovery, whose rate can be facilely speeded up by more than one order through electrostatic gating. Mechanistic investigations of the oxygen switch behavior uncovered a dependence of surface band bending intensity of silicon on oxygen adsorption, which highlights the role of gas molecules, often overlooked, in applications based on semiconductor–liquid interfaces, such as photoelectrochemistry.

Water vapor nucleation on particle's surface plays an important role in dust removal, cloud formation, and particle measurement. However, the selectivity of nucleation sites and the nucleation characteristic of water molecule on the particle's surface are still unclear, especially for the aggregated particles. In this paper, the effects of particle wettability and aggregation modes on the selectivity of nucleation sites and the nucleation characteristics were investigated using molecular dynamics simulation. The results were compared with our earlier experimental findings. It illustrates how the contact angle of clusters, the growth velocity, and the growth duration are all influenced by the interaction coefficient between water and particles. Moreover, the nucleation sites of water molecules on the particle aggregation surface exhibit a definite selectivity. The primary indicator of this selectivity is the preferential nucleation of water molecules at the interfaces of linear chain aggregation particles, at the inner side of non-linear chain aggregation particles, and at the centers of ring aggregation. These results are in good agreement with our previous experimental findings. More significantly, additional research has revealed that subcritical-size clusters typically aggregate on two-particle surfaces spacing when the spacing smaller than the critical cluster size.

Clean, energy-free methods of cooling are an effective way to respond to the global energy crisis. To date, cooling materials using passive daytime radiative cooling (RC) technology have been applied in the fields of energy-efficient buildings, solar photovoltaic cooling, and insulating textiles. However, RC materials frequently suffer from comprehensive damage to their microstructure, resulting in the loss of their initial cooling effect in complex outdoor environments. Here, a superhydrophobic daytime passive RC porous film with environmental tolerance (SRCP film) was fabricated, which integrated strong solar reflectivity (approximately 90%), mid-infrared emissivity (approximately 0.97), and superhydrophobicity (water contact angle (WCA) of 160° and sliding angle of 3°). This study revealed that SRCP film had an average reflectivity of 14.3% higher than SiO2particles in the 0.3–2.5 μm wavelength region, achieving a cooling effect of 13.2 °C in ambient conditions with a solar irradiance of 946 W·m–2and a relative humidity of 74% due to the synergistic effect of effective solar reflection and thermal infrared emission. In addition, empirical results showed that the attained films possessed outstanding environmental tolerance, maintaining high WCA (156°), stable cooling effect (8.3 °C), and low SiO2loss (less than 5.1%) after 30 consecutive days of UV irradiation and 14 days of corrosion with acidic and alkaline solutions. More importantly, this work could be flexibly prepared by various methods without the use of any fluorine-containing reagents, which greatly widens the practical application scope.

Exploring anticorrosion electromagnetic wave (EMW) absorbing materials in harsh conditions remains a challenge. Herein, S-NiSe/HG nanocomposites encapsulated in room-temperature self-healing polyurethane (S-NiSe/HG/SPU) were exploited as superior anticorrosion EMW absorbing materials. A dual-defect engineering collaborative Schottky interface construction endows S-NiSe/HG with a high vacancy concentration, abundant defects, and moderate conductivity. These structural merits synergistically balance dielectric loss by enhancing dipole-interface polarization loss and optimizing conduction loss. As a result, S-NiSe/HG demonstrates the optimal EMW absorption performance with a minimum reflection loss (RLmin) of −54.8 dB and an adequate absorption bandwidth (EAB) of 7.1 GHz. Besides, S-NiSe/HG/SPU combines the maze effect of S-NiSe/HG with the active repair capability of SPU, thereby providing long-term corrosion resistance for the Mg alloy. Even under corrosion for 10 days, S-NiSe/HG/SPU affords a low corrosion current density (1.3 × 10–5A) and high charge transfer resistance (3796 Ω cm2). Overall, this work provides valuable insights for in-depth exploration of dielectric loss and development of multifunctional EMW-absorbing materials.

Current climate forecasting has advanced to the stage of investigating mesoscale air-sea interactions. Recent studies have identified significant structural differences between the cores and edges of mesoscale eddies; however, the effects of these structural variations on air-sea fluxes and the Marine Atmospheric Boundary Layer (MABL) remain underexplored. Traditional observations often fail to capture the detailed structures of eddies, necessitating enhanced observations at high spatiotemporal resolution for mesoscale eddies. To address this, efforts have been made to develop multi-agent platforms and expendable air-sea interface observation technologies. A task-oriented observation scheme was developed to monitor the spatial characteristics of mesoscale eddies. The South China Sea (SCS) is rich in mesoscale eddies with rapid motion changes, requiring enhanced observations of the air-sea interface using multi-agent mobile networking. An anticyclonic eddy was observed in the eastern region of the Xisha Islands in the SCS, and we examined variations in air-sea fluxes across different regions within the eddy.

The rational transformation and utilization of biomass have attracted increasing attention because of its high importance in sustainable development and green economy. In this study, we used a supramolecular approach to convert biomass into functional materials. Six biomass raw materials with distinct chemical structures and physical properties were copolymerized with thioctic acid (TA) to afford poly[TA-biomass]s. The solvent-free copolymerization leads to the convenient and quantitative fabrication of biomass-based versatile materials. The non-covalent bonding and reversible solid–liquid transitions in poly[TA-biomass]s endow them with diversified features, including thermal processability, 3D printing, wet and dry adhesion, recyclability, impact resistance, and antimicrobial activity. Benefiting from their good biocompatibility and nontoxicity, these biomass-based materials are promising candidates for biological applications.

Being an important biomass, glucose can be converted into a range of high-value-added products by oxidation of aldehyde and hydroxyl groups or C–C bond cleavage. In contrast with conventional approaches (e.g., microbial fermentation, and thermocatalysis), conversion of glucose by photocatalysis, electrocatalysis, and photoelectrocatalysis is conducted under mild conditions free of any strong oxidants, which are highly valuable for economical and environmental benefits. In this review, we comprehensively summarize the various catalytic systems (e.g., catalysts, conversion, yields, and mechanisms) for photocatalytic, electrocatalytic, and photoelectrocatalytic conversion of glucose. Emphasis is put on the correlation of the catalytic performance with the catalyst structures. The underlying mechanisms of glucose oxidation by the catalysts were elaborated. The integrated systems coupling glucose conversion with hydrogen production were comparatively evaluated, affording information for further development of novel catalytic systems. Finally, challenges, and future perspectives on glucose conversion by photocatalysis, electrocatalysis, and photoelectrocatalysis are proposed.

The use of fertilizer is a routine method of soil improvement, and thereby fertilizer is considered as an emerging factor affecting the transport of plastic particles in agricultural soils. Nano-CaCO3was selected as a representative nano-fertilizer to investigate its effect on the transport and release of nano- and micro-plastics (NPs and MPs) in saturated porous media. The effect of 200 mg L−1nano-CaCO3on the transport of nano- (0.51 μm, PS NPs) and micro- (1.1 μm, PS MPs) polystyrene particles (5 mg L−1) in saturated quartz sand was investigated. Nano-CaCO3facilitated both the transport and release of PS NPs and MPs in examined 0.1–10 mM NaCl and 0.1–1 mM CaCl2solutions. In addition, it was believed that the remaining deposition of PS NPs and MPs after copresent nano-CaCO3and release treatment was solid and stable, as evidenced by the negligible detachment of PS NPs and MPs with deionized water washing. Further investigation indicated that the competition for deposition sites on quartz sand surfaces by nano-CaCO3copresent in solutions was the major factor dominating the enhanced transport of both PS NPs and MPs. This was verified by the transport of single nano-CaCO3, the increased transport of PS NPs and MPs in quartz sand that was subjected to pre-equilibration with nano-CaCO3and also the SEM images of quartz sand covered with nano-CaCO3. Meanwhile, the sweeping effects induced by nano-CaCO3were found to be responsible for the enhanced release of PS NPs and MPs during the transport process. This was further confirmed by the relatively high surface area and roughness of nano-CaCO3and the fluorescence microscopy imaging of the detached particles in effluents of column experiments of PS NPs and MPs induced by nano-CaCO3. The findings of this study give insights into assessing the ecological risks of plastic particles with agrochemicals.

A label-free addressable photoelectric immunosensor array was designed for the detection of amyloid β-proteins based on magnetic separation and self-calibration strategies. In this paper, Na2Ti6O13with a flower-like morphology was prepared by the hydrothermal method; after continuously combining Fe3O4and CdS, it was endowed with magnetism and better photoelectric activity. Subsequently, a series of reactions occurred in the solution, and the magnetic separation method was used to enrich the target. On the other hand, the ITO glass was separated into eight sites (2 × 4) using magnets, and a light shield was utilized to prevent light exposure, resulting in addressable and continuous detection. After the uniform preparation of magnetic photoelectric materials and precise control of testing conditions, the relative errors among different sites have been effectively reduced. Moreover, incorporating a self-calibration strategy has allowed the sensor array to achieve greater accuracy. The proposed photoelectrochemical biosensor exhibits a good relationship with amyloid β-protein ranging from 0.01 to 100 ng mL–1with a limit of detection of 1.1 pg mL–1and exhibits excellent specificity, reproducibility, and stability.

An electrochemical strategy for the decarboxylative elimination of carboxylic acids to alkenes at room temperature has been developed. This mild and oxidant-free method provides a green alternative to traditional thermal decarboxylation reactions. Structurally diverse aliphatic carboxylic acids, including biologically active drugs, underwent smooth conversion to the corresponding alkenes in good to excellent yields.

Single-walled carbon nanotube (SWCNT)-based thermoelectric materials have been extensively studied in the field of flexible wearable devices due to their high flexibility and excellent electrical conductivity (σ). However, poor Seebeck coefficient (S) and high thermal conductivity limit their thermoelectric application. In this work, free-standing MoS2/SWCNT composite films with improved thermoelectric performance were fabricated by doping SWCNTs with MoS2nanosheets. The results demonstrated that the energy filtering effect at the MoS2/SWCNT interface increased the Sof composites. In addition, the σ of composites was also improved due to the reason that S–π interaction between MoS2and SWCNTs made good contact between MoS2and SWCNTs and improved carrier transport. Finally, the obtained MoS2/SWCNT showed a maximum power factor of 131.9 ± 4.5 μW m–1K–2at room temperature with a σ of 680 ± 6.7 S cm–1and an Sof 44.0 ± 1.7 μV K–1at a MoS2/SWCNT mass ratio of 15:100. As a demonstration, a thermoelectric device composed of three pairs of p–n junctions was prepared, which exhibited a maximum output power of 0.43 μW at a temperature gradient of 50 K. Therefore, this work offers a simple method of enhancing the thermoelectric properties of SWCNT-based materials.

The market for on-demand mobility services is growing worldwide. These services include, for example, ride-hailing, ride-sharing, and car-sharing. Large-scale fleets of such services collect GPS trajectory (probe vehicle) data constantly everywhere in the network. At a certain penetration rate, this data becomes representative of the entire road network. It can give valuable insights into traffic dynamics and the evolution of congestion. In this paper, we use such GPS trajectory data from Chengdu, China, to investigate the stability and recurrence of macroscopic traffic patterns. Using the two-fluid theory, we find that the two-fluid coefficients are robust on between-day variation, not only supporting the theory itself but also emphasizing that the general evolution of traffic is a robust pattern. We investigate the deviations from the model using time series analysis of the residuals of the two-fluid model. Here, we find evidence for daily and weekly seasonality in the residuals, indicating that congestion patterns are convincingly recurring. These patterns can be used for network-wide traffic state prediction. We conclude that GPS trajectory data from large on-demand mobility fleets is a promising data source for observing traffic patterns in urban road networks once the data becomes representative.

An electricity-promoted method for Friedel–Crafts acylation of biarylcarboxylic acids is described in this research. Various fluorenones can be accessed in up to 99% yields. During the acylation, electricity plays an essential role, which might motivate the chemical equilibrium by consuming the generated TFA. This study is predicted to provide an avenue to realize Friedel–Crafts acylation in a more environmentally friendly process.

A 5-T MRI system provided similar image quality compared with 7 T but higher image quality than 3-T images when evaluating intracranial vessels and associated small branches.

The curvature of two-dimensional function can describe the degree of surface curvature. When an image is treated as a discrete two-dimensional function, image curvature describes the structural relationship between local pixels of the image. Local ternary pattern is an effective image texture descriptor to encode shape index based on image curvature. In this paper, the completed local ternary pattern, which contains the symbol characteristics, amplitude characteristics and central pixel characteristics of the local ternary pattern of shape index (completed local ternary pattern based on shape index, SI-CLTP) are all considered at the same time. Experiments on two texture databases and one palmprint database fully show that shape index based completed local ternary pattern is an effective image texture descriptor.

• A novel Co@NC@MoS 2 magnetic hierarchical nanotube is designed and prepared. • The minimum reflection loss (RL min) exceeds −61.97 dB. • The effective absorption bandwidth (EAB) covers 5.6 GHz. • The electromagnetic parameters can be adjusted by changing the load of MoS 2. In this study, a new lightweight one-dimensional absorber Co@NC@MoS 2 was designed and prepared. Firstly, polydopamine (PDA) was coated by oxidative self-polymerization with cobalt-nitrilotriacetic acid chelate nanowires (Co-NTAC) as template. Then core-shell structured magnetic hierarchical nanotubes (Co@PDA@MoS 2) were prepared by one-step hydrothermal method. After thermal annealing, PDA layer was transformed into nitrogen doped carbon layer (NC) to obtain the efficient microwave absorber Co@NC@MoS 2. The removal of template and growth of MoS 2 were completed simultaneously, the preparation process was simplified. Because of its good magnetic loss and dielectric loss, Co@NC@MoS 2 shows excellent microwave absorption performance. Under filler content of 15 wt.%, the minimum reflection loss (RL min) can reach -61.97 dB@9.2 GHz, and the effective absorption bandwidth (EAB) is 5.6 GHz. The electromagnetic parameters of Co@NC@MoS 2 can be further adjusted by changing the load of MoS 2. Meanwhile, the structure and composition of Co@NC@MoS 2 were systematically analyzed. The influence of the microstructure on the microwave absorbing properties was investigated, and the microwave attenuation mechanism is revealed. As an efficient and lightweight absorber, Co@NC@MoS 2 has potential application value in the construction of new stealth coatings. [ABSTRACT FROM AUTHOR]

Flexible wearable electronics have received tremendous attention for their potential in electronic skins, wearable healthcare monitoring, and human-machine interfacing. However, it remains a critical challenge to simultaneously achieve wearable epidermic sensing with broad sensing range, fast response/recovery time, and perfect conformability onto skin to realize human healthcare and tiny electrophysiological signals. Meanwhile, traditional epidermic sensors cannot accommodate multistimuli-responsive actuation, which greatly restricts their potential in artificial muscles, intelligent soft robots, and smart switches. Herein, inspired by nacre with unique “brick-and-mortar” structure and excellent mechanical performance, the nacre-like intercalated MXene nanocomposite film is prepared by facile water-evaporation-induced self-assembly, which could be assembled as flexible multifunctional electronics for wearable epidermic sensing and multiresponsive actuation. This work provides a facile strategy for fabricating bioinspired nacre-like intercalated two-dimensional-material-contained nanocomposites with excellent sensing performance and outstanding actuating capability simultaneously for versatile applications in healthcare monitoring, intelligent soft robots, smart switches, and human-machine interfacing.

Muscle fatigue, as a serious social problem, affects the performance of daily living activities, especially for workers. Decrease of movement control ability caused by muscle fatigue is one of the risk and intrinsic factors for occupational accidents, such as slips, trips, falls, etc. In order to reduce the accident rate and optimize the existing prevention measures, it is necessary to investigate the effect of fatigue on kinematics, kinetics, and muscle activities of human body. In this paper, 26 healthy participants were recruited. The kinematics and kinetics analysis of lower limb joints, and surface electromyograms (sEMG) time-domain and frequency-domain analysis of lower limb periarticular muscles were utilized to investigate the effects of muscle fatigue. The results showed that the fatigue reduced the range-of-motion (RoM) of the lower limb joints. Smaller plantarflexion, knee flexion and hip flexion angles, and greater dorsiflexion angles were observed after fatigue. For the joint moment, the fatigue did not alter the joint moments except for the smaller knee flexion moment. For the joint power, the fatigue decreased the generation power of ankle, knee and hip joint and the absorption power of ankle and knee joints, whereas increased the absorption power of hip joint. Besides, the fatigue increased the normalized integrated sEMG (iEMG) and root-mean-square (RMS) of sEMG, and shifted the median frequency (MF) and mean power frequency (MPF) of sEMG toward lower frequencies. The results from the present study concluded that the muscle fatigue changed the kinematics, kinetics and muscle activities of lower limbs during gait, and then could increase the risk rate of occupational accidents.

Herein we report an electrochemical strategy for the construction of polysubstituted oxazoles from easily available ketones and acetonitrile under room temperature. The method shows high efficiency, a broad substrate scope, and requires no external chemical oxidant. Mechanistic investigations suggest that the reaction proceeds through a Ritter-type reaction/oxidative cyclization using acetonitrile as the reactant and solvent. X-ray crystallographic analysis reveals that the reaction involves the attack of acetonitrile on the carbonyl carbon instead of the α-carbon.

The tumor microenvironment (TME) was usually studied in tumor tissue and in relation to only tumor progression, with little involved in occurrence, recurrence and metastasis of tumor. Thus, a new concept “peritumor microenvironment (PME)” was proposed in the proteomic characterization of peritumor liver tissues in human hepatocellular carcinoma (HCC). The PME for occurrence (PME-O) and progression (PME-P) were almost totally different at proteome composition and function. Proteins for occurrence and progression rarely overlapped and crossed. Immunity played a central role in PME-O, whereas inflammation, angiogenesis and metabolism were critical in PME-P. Proteome profiling identified three PME subtypes with different features of HCC. Thymidine phosphorylase (TYMP) was validated as an antiangiogenic target in an orthotopic HCC mouse model. Overall, the proteomic characterization of the PME revealed that the entire processes of HCC occurrence and progression differ substantially. These findings could enable advances in cancer biology, diagnostics and therapeutics.

Ultraprecision optical systems such as high-energy laser systems have very strict requirements for surface defects of optical components. Comet-shaped defects are common in magnetorheological finishing, which is one of the main ultraprecision manufacturing technologies. Computational fluid dynamics is used to simulate the pressure and velocity of the magnetorheological fluid in pits during magnetorheological finishing for the first time, to the best of our knowledge. The simulation model analyzes the distribution of velocity and pressure in the process of the formation of comet-shaped defects. After the simulation, magnetorheological polishing experiments were carried out on the fused quartz silica glass. The polishing experiments use the rotation speed and immersion depth of the polishing wheel to verify the velocity and pressure distribution in the simulation experiment. The polishing experiment results are consistent with the simulation results, which show that the high polishing speed will increase the depth of the defect, and the uneven velocity and pressure distribution at the pits make the pits evolve into comet-shaped defects. We explain the cause of comet-shaped defects from the perspective of material removal and provide an optimization method of process parameters for high-efficiency removal of comet-shaped defects.

Currently developed adhesives are overwhelmingly polymeric in nature. Herein, we highlight for the first time the potential of supramolecular eutectogels assembled from small molecules as robust low-molecular-weight (LMW) supramolecular adhesives in air, water and organic solvents, and under low temperatures. These supramolecular eutectogels were produced from commercial alkyl trimethyl ammonium bromide (CnTAB) in emerging deep eutectic solvents (DESs), which demonstrated rapid (∼2 min), robust, and tunable adhesion to both hydrophilic and hydrophobic surfaces at room temperature in air. Moreover, high adhesion performance was maintained even in liquid nitrogen (−196 °C), underwater, and in organic solvents. A study of the structure–property relationship of these adhesives and molecular dynamics (MD) simulations further clarified the assembly and adhesion mechanism of the C12TAB molecules in DESs. Compared with traditional polymer adhesives and several existing examples of LMW supramolecular adhesives with solvent-free dry network structures, the spontaneous self-assembly of LMW gelators in versatile DESs provides a new strategy for the facile construction of high-strength supramolecular adhesives with gel network structures for a diverse range of harsh environments.

Purpose: To further assess the diagnostic performance of positron emission tomography/computed tomography (PET/CT) in recurrent renal cell carcinoma (RCC) patients. Methods: Relevant studies published from February 1, 1987, to October 14, 2022, were selected by searching Embase, PubMed, and Web of Science. The data were extracted on characteristics of studies and patients, technical aspects of the articles, as well as the results of 18F-FDG PET/CT with histologic pathology or follow-up imaging of true-positive, true-negative, false-positive, and false-negative data. Then the publication bias was assessed with Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool and Deek's funnel plot test. And a meta-regression analysis was performed to evaluate the data with clinical significance to locate the sources of heterogeneity. Results: Eleven studies were confirmed to the requirements, covering a total of 1307 patients. Sensitivity and specificity were 0.95 (95% CI, 0.90–0.98) and 0.95 (95% CI, 0.88–0.98), respectively, and the area under the curve (AUC) of the summary receiver-operating characteristic (SROC) was 0.99 (95% CI, 0.97–0.99), without evidence of publication bias. Conclusion: 18F-FDG PET/CT could serve as a prominent surveillance technique with robust diagnostic performance in detecting recurrence in RCC patients, which may be adopted as a routine monitoring strategy for advanced RCC. However, further prospective studies are still required to demonstrate more thorough and precise performance metrics.