Search Results (381)

The inherent hydrophobic nature of PVDF material renders it challenging to establish a stable aqueous hydration layer, thereby limiting its suitability as a substrate for the preparation of nanofiltration (NF) membranes. In this study, we developed a novel modification approach that effectively enhances the hydrophilicity of PVDF substrates through the incorporation of sulfonic acid-doped polyaniline (SPANI) and hyperbranched polyester (HPE) into the PVDF casting solution, followed by cross-linking with trimesoyl chloride (TMC). The introduction of SPANI and HPE, which contain reactive polar amino and hydroxyl groups, improved the hydrophilicity of the substrate, while the subsequent cross-linking with TMC effectively anchored these components within the substrate through the covalent linking between TMC and the reactive sites. Additionally, the hydrolysis of TMC yielded non-reactive carboxyl groups, which further enhanced the hydrophilicity of the substrate. As a result, the modified PVDF substrate exhibited improved hydrophilicity, facilitating the construction of an intact polyamide layer. In addition, the fabricated TFC NF membrane demonstrated excellent performance in the advanced treatment of tap water, achieving a total dissolved solid removal rate of 57.9% and a total organic carbon removal rate of 85.3%. This work provides a facile and effective route to modify PVDF substrates for NF membrane fabrication. Full article

Background and Objectives: Magnesium (Mg)-based materials, such as the WE43 alloy, show potential in biomedical applications owing to their advantageous mechanical properties and biodegradability; however, their quick corrosion rate and hydrogen release restrict their general clinical utilization. This study aimed to develop a novel Mg-Zn-Ca alloy system based on WE43 alloy, evaluating the influence of Zn and Ca additions on microstructure, mechanical properties, cytocompatibility, and electrochemical behavior for potential use in biodegradable orthopedic applications. Materials and Methods: The WE43-Zn-Ca alloy system was developed by alloying standard WE43 (Mg–Y–Zr–RE) with 1.5% Zn and Ca concentrations of 0.2% (WE43_0.2Ca alloy) and 0.3% (WE43_0.3Ca alloy). Microstructural analysis was performed utilizing scanning electron microscopy (SEM) in conjunction with energy-dispersive X-ray spectroscopy (EDS), while the chemical composition was validated through optical emission spectroscopy and X-ray diffraction (XRD). Mechanical properties were assessed through tribological tests. Electrochemical corrosion behavior was evaluated using potentiodynamic polarization in a 3.5% NaCl solution. Cytocompatibility was assessed in vitro on MG63 cells using cell viability assays (MTT). Results: Alloys WE43_0.2Ca and WE43_0.3Ca exhibited refined, homogeneous microstructures with grain sizes between 70 and 100 µm, without significant structural defects. Mechanical testing indicated reduced stiffness and an elastic modulus similar to human bone (19.2–20.3 GPa), lowering the risk of stress shielding. Cytocompatibility tests confirmed non-cytotoxic behavior for alloys WE43_0.2Ca and WE43_0.3Ca, with increased cell viability and unaffected cellular morphology. Conclusions: The study validates the potential of Mg-Zn-Ca alloys (especially WE43_0.3Ca) as biodegradable biomaterials for orthopedic implants due to their favorable combination of mechanical properties, corrosion resistance, and cytocompatibility. The optimization of these alloys contributed to obtaining an improved microstructure with a reduced degradation rate and a non-cytotoxic in vitro outcome, which supports efficient bone tissue regeneration and its integration into the body for complex biomedical applications. Full article

Synchronous fluorescence spectra are presented to investigate solute–solvent interactions in liquids. To this end, the spectra of 2-amino-7-nitro-fluorene (ANF) in six different solvents—acetic anhydride, acetone, acetonitrile, benzene, chlorobenzene, and ethyl acetate—are presented. The study also examines ANF’s synchronous fluorescence signals at five temperatures from 25 °C to 5 °C, providing a comprehensive analysis of its fluorescence characteristics in different environments and temperatures. An ANF sample dissolved in benzene at 5 °C produced a synchronous band with the largest intensity and smallest frequency shift. The results show that higher-intensity peaks are obtained at lower temperatures with solvents with a small dipole moment and dielectric constant. This suggest that the best conditions to detect ANF and similar molecules at very low concentrations are with non-polar solvents at low temperatures. Full article

More than 70% of the information humans acquire from the external environment is derived through the visual system, where photosensitive function plays a pivotal role in the biological perception system. With the rapid development of artificial intelligence and robotics technology, achieving human-like visual perception has attracted a great amount of attention. The neuromorphic visual perception system provides a novel solution for achieving efficient and low-power visual information processing by simulating the working principle of the biological visual system. In recent years, ferroelectric materials have shown broad application prospects in the field of neuromorphic visual perception due to their unique spontaneous polarization characteristics and non-volatile response behavior under external field regulation. Especially in achieving tunable retinal neural synapses, visual information storage processing, and constructing dynamic visual sensing, ferroelectric materials have shown unique performance advantages. In this review, recent progress in neuromorphic visual perception based on ferroelectric materials is discussed, elaborating in detail on device structure, material systems, and applications, and exploring the potential future development trends and challenges faced in this field. Full article

Additive Manufacturing (AM), as a revolutionary breakthrough in advanced manufacturing paradigms, leverages its unique layer-by-layer construction advantage to exhibit significant technological superiority in the fabrication of complex structural components for aerospace, biomedical, and other fields. However, when addressing industrial-grade precision manufacturing requirements, key challenges such as the multi-scale characteristics of surface damage precursors, interference from background noise, and the scarcity of high-quality training samples severely constrain the intelligent transformation of AM quality monitoring systems. This study proposes an innovative microscopic polarization YOLOv11-LSF intelligent inspection framework, which establishes an automated non-destructive testing methodology for AM device micro-nano damage precursors through triple technological innovations, effectively breaking through existing technical bottlenecks. Firstly, a multi-scale perception module is constructed based on the Large Separable Kernel Attention mechanism, significantly enhancing the network’s feature detection capability in complex industrial scenarios. Secondly, the cross-level local network VoV-GSCSP module is designed utilizing GSConv and a one-time aggregation method, resulting in a Slim-neck architecture that significantly reduces model complexity without compromising accuracy. Thirdly, an innovative simulation strategy incorporating physical features for damage precursors is proposed, constructing a virtual and real integrated training sample library and breaking away from traditional deep learning reliance on large-scale labeled data. Experimental results demonstrate that compared to the baseline model, the accuracy (P) of the YOLOv11-LSF model is increased by 1.6%, recall (R) by 1.6%, mAP50 by 1.5%, and mAP50-95 by 2.8%. The model hits an impressive detection accuracy of 99% for porosity-related micro-nano damage precursors and remains at 94% for cracks. Its unique small sample adaptation capability and robustness under complex conditions provide a reliable technical solution for industrial-grade AM quality monitoring. This research advances smart manufacturing quality innovation and enables cross-scale micro-nano damage inspection in advanced manufacturing. Full article

Gas chromatography–ion mobility spectrometry (GC-IMS) is an interesting candidate to face geographical origin declaration fraud in dehydrated apple samples. It allows the collection of the peculiar fingerprints of the analysed samples with the bi-dimensional separation of volatile molecules, based on their polarity and their dimension and shape. It represents a rapid, cost-effective, and sensitive solution for food authenticity issues. A design of experiment (DoE) led to robust sampling, taking into account different factors, such as harvesting year, the presence of peel, variety. The sample preparation was limited as it required only the milling of the dehydrated apple dices before the analysis. The GC-IMS analytical method permitted us to obtain of a 3D graph in 11 min, and the multivariate statistical analysis returned a clear separation between Italian and non-Italian (French, Chinese, Hungarian, Polish) samples, considering both unsupervised and supervised approaches. The statistical model, created employing a training set, was applied on a further test set, with a good overall performance. Thus, GC-IMS could play a relevant role as a tool to prevent/fight false origin declaration frauds and also, potentially, other kinds of food authenticity and safety frauds. Full article

Spectrally selective infrared absorbers play a pivotal role in enabling optoelectronic applications such as infrared detection, thermal imaging, and photothermal conversion. In this paper, a dual-band wide-spectrum infrared selective absorber based on a metal–dielectric multilayer structure is designed. Through optimized design, the absorptance of the absorber reaches the peak values of 0.87 and 1.0 in the target bands (3–5 μm and 8–14 μm), while maintaining a low absorptance of about 0.2 in the non-working bands of 5–8 μm, with excellent spectral selectivity. By analyzing the Poynting vector and loss distribution, the synergistic mechanism of the ultra-thin metal localized enhancement effect, impedance matching, and intrinsic absorption of the material is revealed. This structure exhibits good polarization-insensitive characteristics and angle robustness within a large incident angle range, showing strong adaptability to complex optical field environments. Moreover, the proposed planarized structure design is compatible with standard fabrication processes and has good scalability, which can be applied to other electromagnetic wave bands. This research provides new design ideas and technical solutions for advanced optoelectronic applications such as radiation cooling, infrared stealth, and thermal radiation regulation. Full article

Polarization navigation is an emerging navigation technology, that exhibits significant advantages, including strong anti-interference capability and non-cumulative errors over time, making it highly promising for applications in aerospace, autonomous driving, and robotics. To address the requirements of high integration and low power consumption for tri-directional polarization navigation sensors, this study proposes a system-on-chip (SoC) design solution. The system employs the ZYNQ MPSoC (Xilinx Inc., San Jose, CA, USA) as its core, leveraging hardware acceleration on the Programmable Logic (PL) side for three-angle polarization image data acquisition, image preprocessing, and edge detection. Simultaneously, the Processing System (PS) side orchestrates task coordination, performs polarization angle resolution, and extracts the solar meridian via Hough transform. Experimental results demonstrate that the system achieves an average heading angle output time interval of 9.43 milliseconds (ms) with a mean error of 0.50°, fulfilling the real-time processing demands of mobile devices. Full article

This study reports the synthesis and characterization of two solvatochromic pentacyanoferrate(II) complexes. Their structural design incorporates ligands with flexible xylylene bridges and distinct heterocycles—one combining 4-dimethylaminopyridine (DMAP) with 4,4′-bipyridine, and the other isoquinoline with 4,4′-bipyridine. Their structural diversity enables the complexes to engage in a broad range of solvent–solute interactions, providing valuable insights into the behavior of solvents and media with regard to polarity, through sizable solvatochromic shifts. Their solvatochromism is examined using a set of nine solvents and solvent mixtures. The solvatochromic sensitivities to polarity changes, expressed through a variety of polarity parameters and functions, are determined. Moreover, using a set of four complementary linear solvation energy relationships (LSERs), the roles of solvent polarity, solute–solvent interactions and the molecular responsiveness of the two compounds to different media are investigated. Additionally, their dipole moments in the ground and MLCT-excited states are determined using a suitable model, namely that of Suppan and Tsiamis. As a step further, the polarity sensing aptitude of the two solvatochromic compounds is examined in aqueous urea solutions at varying urea concentrations. The solvatochromic sensitivity of the two compounds is compared with that of a model cyanoferrate(II) complex, Fe^II(CN)₂(phen)₂. The two compounds clearly surpass the sensitivity of Fe^II(CN)₂(phen)₂ with subtle solvent polarity changes induced by varying the urea concentration. An LSER describing and predicting the solvatochromic effects in aqueous urea is developed and tested. Full article

Paeonia ludlowii is a threatened and valuable germplasm in the cultivated tree peony gene pool, with distinctive traits such as tall stature, pure yellow flowers, and scarlet foliage in autumn. However, the crossability barrier limits gene transfer from P. ludlowii to cultivated tree peony. Therefore, our study investigated the reasons for the lack of crossability between P. ludlowii and Paeonia ostii ‘Fengdan’. Distant cross pollination (DH) resulted in the formation of many calloses at the ends of the pollen tubes, which grew non-polar, twisted, entangled, and often stopped in the style. Pollen tubes elongated the fastest in self-pollination (CK), and pollen tubes elongated faster and fewer pollen tube abnormalities were observed in stigmas treated with KCl solution before pollination (KH) than in DH. During pollen–pistil interactions, the absence of stigma exudates, high levels of H₂O₂, O₂⁻, MDA, ^•OH, ABA, and MeJA, and lower levels of BR and GA₃ may negatively affect pollen germination and pollen tube elongation in the pistil of P. ostii ‘Fengdan’. Pollen tubes in CK and KH penetrated the ovule into the embryo sac at 24 h after pollination, whereas only a few pollen tubes in DH penetrated the ovule at 36 h after pollination. Pre-embryo abnormalities and the inhibition of free nuclear endosperm division resulted in embryo abortion in most of the fruits of DH and many fruits of KH, which occurred between 10 and 20 days after pollination, whereas embryos in CK developed well. Early embryo abortion and endosperm abortion in most of the fruits of DH and KH led to seed abortion. Seed abortion in KH and DH was mainly due to an insufficient supply of auxins and gibberellins and lower content of soluble protein and soluble sugars. The cross failure between P. ludlowii and P. ostii ‘Fengdan’ is mostly caused by a pre-fertilization barrier. KH treatment can effectively promote pollen tube growth and facilitate normal development of hybrid embryos. These findings provide new insights into overcoming the interspecific hybridization barrier between cultivated tree peony varieties and wild species. Full article

This paper presents a non-contact method for detecting the sugar concentration in solutions based on real-time polarization characteristics and an interaction effects model. The feasibility of using polarization imaging technology for sugar concentration detection is analyzed. By analyzing the Stokes parameters, a linear regression model is developed to establish the interaction effects between sugar concentration and both the degree of linear polarization (DoLP) and the angle of linear polarization (AoLP). A three-beam polarization imaging system is used to simultaneously capture the polarization images of sucrose solutions with varying concentrations, and the SIFT algorithm is employed to eliminate image shifts. The results show a strong linear correlation between sugar concentration and both AoLP (R² = 0.998) and DoLP (R² = 0.968). The addition of the interaction effect model significantly improves the prediction accuracy, with an RMSE of 0.36934 and a relative error within ±5%. This method features a simple experimental setup, enables multi-angle simultaneous measurements, and offers advantages such as non-contact operation, ease of use, and high precision (average relative error < 5%). It provides a new approach for sugar concentration detection in food, industry, and other fields. Full article

Imaging technologies based on vector optical fields hold significant potential in the biomedical field, particularly for non-invasive scattering imaging of anisotropic biological tissues. However, the dynamic and anisotropic nature of biological tissues poses severe challenges to the propagation and reconstruction of vector optical fields due to light scattering. To address this, we propose a deep learning-based polarization-resolved restoration method aimed at achieving the efficient and accurate imaging reconstruction from speckle patterns generated after passing through anisotropic and dynamic time-varying biological scattering media. By innovatively leveraging the two orthogonal polarization components of vector optical fields, our approach significantly enhances the robustness of imaging reconstruction in dynamic and anisotropic biological scattering media, benefiting from the additional information dimension of vectorial optical fields and the powerful learning capacity of a deep neural network. For the first time, a hybrid network model is designed that integrates convolutional neural networks (CNN) with a Transformer architecture for capturing local and global features of a speckle image, enabling adaptive vectorial restoration of dynamically time-varying speckle patterns. The experimental results demonstrate that the model exhibits excellent robustness and generalization capabilities in reconstructing the two orthogonal polarization components from dynamic speckle patterns behind anisotropic biological media. This study not only provides an efficient solution for scattering imaging of dynamic anisotropic biological tissues but also advances the application of vector optical fields in dynamic scattering environments through the integration of deep learning and optical technologies. Full article

Gallium nitride (GaN), an advanced piezoelectric semiconductor, shows strong potential for ultraviolet (UV) applications due to its prominent thermoelectric, photoelectric, and mechanoelectrical coupling effects, all of which are critical to device performance. This paper focuses on one-dimensional GaN nanowires and introduces a nonlinear theoretical model to describe pyroelectric and photoelectron effects under UV excitation. The model accounts for both photothermal and photoconductive effects. Using the perturbation method, we derive an approximate analytical solution for the internal physical field of the nanowire under UV light irradiation, which aligns well with the results from nonlinear numerical simulations. Compared to a light intensity of 2 W/m², a light intensity of 6 W/m² leads to a 45% increase in electron concentration, a 235% rise in hole concentration, a 146% increase in potential, and a 274% increase in polarization charge concentration. The pyro-phototronic effect enables UV light to modulate the electrical transport characteristics of a Schottky junction. This study addresses the limitations of linearized models for handling large disturbances, providing a comprehensive theoretical and computational framework for advancing GaN micro- and nanoscale devices and enabling effective, non-contact control. Full article

It has been demonstrated that when a low-molecular-weight salt solution flows through a polyelectrolyte gel, an electromotive force is generated, and its polarity depends on the sign of the polyelectrolyte network’s charge. A mathematical model proving the possibility of developing a device for separating a solution of low-molecular salt into enriched and depleted phases under the influence of gravitational forces has been developed. Such a device contains a system of parallel columns filled with different kinds of cross-linked polyelectrolyte networks. The proposed mathematical model is grounded in the theory of double electrical layers forming at the hydrogel/solution interface; these layers deform under non-equilibrium conditions, specifically during the flow of the solution through the cross-linked polyelectrolyte network. An analogous model is proposed describing the case of an analogous device based on an electric current passing through two oppositely charged contacting networks, which provides the possibility of separating the initial solution into enriched and the depleted phases too. The practical applications of the found effect are discussed. In particular, it is demonstrated that a wide number of measurement electronic devices can be created on such a base, including devices to be used within the investigation of polyelectrolyte hydrogels of different types. Full article

Background: Our recent findings, of the highest survival rate of animals that consumed moderate amounts of white wine for four weeks prior to surgically induced myocardial infarction by the ligation of the left anterior descending artery, prompted us to investigate the inflammatory aspects of the post-infarction healing process. In order to examine whether the effects of wine consumption differ from that of ethanol, experimental animals were randomized into three groups: white wine, 13% v/v ethanol/water or water-only controls. Methods: Hearts for immunohistochemical analysis were collected from animals that survived 96 h after infarction, consumed no less than 8 mL of white wine or ethanol/water solution per day and had transmural infarcts of comparable sizes. After accounting for all of the above criteria, the final number of animals was seven per group. Tissue slices were stained with a pan-macrophage marker CD68 and an anti-inflammatory macrophage marker CD163 to investigate macrophage polarization that is crucial for the inflammatory aspects of post-infarction healing. Immunofluorescent imaging was performed on four zones surrounding the infarcted area with detritus: subepicardial, subendocardial and two peri-infarct zones. Results: The largest CD163/CD68 ratios for comparable volumes of alcohol consumption were observed in the wine group in all zones. CD163/CD68 ratios decreased in both the ethanol and wine group as the average amount of alcoholic beverage consumed by the animals increased. Conclusions: Our results indicate that non-alcoholic constituents of white wine contribute to its superior effects in the favorable modulation of post-infarction inflammation and healing processes relative to that of ethanol alone. Full article