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Lithography is a core-pattern transfer technique in micro/nanofabrication, among which electron-beam lithography (EBL) is a representative example. Polymethyl methacrylate (PMMA) has been widely employed as an electron-beam resist due to its high sensitivity, high resolution, and excellent contrast. However, commercial PMMA resists are relatively expensive and have complex formulations, thereby limiting process flexibility and cost control. Here, we demonstrate a rapid, low-cost preparation method for a PMMA resist suitable for micrometer-scale EBL. PMMA powder was dissolved in anisole to obtain a 4 wt% solution, which was spin-coated onto substrates to form uniform and smooth thin films. To evaluate resist performance, a custom-designed 5 × 5 array pattern was used to systematically study the effect of exposure dose on pattern quality. Results show that doses below 200 μC/cm² fail to induce complete scission of the PMMA molecular chains. Thermal evaporation and a lift-off process were employed to verify the dimensional accuracy of fabricated electrodes. Within the exposure dose range of 240–270 μC/cm², the electrode patterns were complete and exhibited straight edges. The optimal pattern fidelity was achieved at 260 μC/cm², with an absolute dimensional error below 0.2 μm, meeting the precision requirements of most micro/nanofabrication applications. This work provides a practical process reference for the preparation of PMMA electron-beam resists and their application in nanodevice fabrication.

[b]Background:[/b] Effective pain control is often limited by the short duration and systemic side effects of conventional lidocaine administration. Transdermal delivery systems offer a non-invasive alternative, but require materials that match skin mechanics and provide sustained drug release. [b]Methods:[/b] We designed a stretchable, biodegradable elastomer patch composed of a Poly(glycerol sebacate) (PGS) top layer and a lidocaine-loaded Poly(lactic-co-glycolic acid) (PLGA) reservoir. The patch’s mechanical properties, degradation behavior, drug release kinetics, transdermal permeation, and analgesic efficacy were systematically evaluated in vitro and in vivo. [b]Results:[/b] The patch exhibited a skin-like modulus and remained flexible during deformation. In vitro, it sustained lidocaine release over 48 h and degraded to ~20% mass over 30 days. Franz cell experiments confirmed effective skin permeation. In a rodent model, the patch significantly increased paw withdrawal thresholds compared to free drug. [b]Conclusion:[/b] This multilayer elastomer patch provides conformal adhesion, sustained lidocaine release, and enhanced local analgesia, offering a promising platform for non-invasive, long-acting pain management.

[b]Objective:[/b] To investigate and optimize the alkaline extraction process of Ganoderma lucidum polysaccharides, and to preliminarily explore their immunological activity. [b]Methods:[/b] Ganoderma lucidum was used as the raw material for the extraction of polysaccharides. A single-factor experiment was conducted to examine the effects of NaOH concentration, temperature, and extraction time on the total sugar content of the polysaccharides. Based on these results, response surface methodology was applied to optimize the extraction process. The total polysaccharide content, uronic acid content, monosaccharide composition, molecular weight, and cell viability were measured. [b]Results:[/b] The optimal extraction conditions were found to be a temperature of 93◦C, NaOH concentration of 0.40 mol/L, and extraction time of 172 min, yielding a total polysaccharide content of 47.66%. The monosaccharide composition of the extracted polysaccharides included mannose, glucuronic acid, glucose, galactose, arabinose, and fucose. Molecular weight analysis revealed two average molecular weights, 3.15 × 104 Da and 1.014 × 104 Da, indicating the polysaccharides were relatively small. Infrared spectroscopy showed the presence of β-type glycosidic linkages in the polysaccharides. In the cell viability assay, GLCP-1 enhanced the viability of RAW264.7 cells and significantly inhibited the viability of HepG2 cells. However, the specific regulatory mechanism remains unclear. [b]Conclusion:[/b] The study successfully optimized the alkaline extraction of Ganoderma lucidum polysaccharides and demonstrated their potential immunological activity, providing a foundation for the future exploration of their bioactivity and industrial production.

Clopidogrel is widely used for stroke prevention, but its oral administration is limited by poor patient adherence, gastrointestinal irritation, and hepatic first-pass metabolism. To address these limitations, we developed a biodegradable microneedle patch composed of poly(lactic-co-glycolic acid) (PLGA) and polyvinylpyrrolidone (PVP) for the transdermal delivery of clopidogrel. The patch exhibited sufficient mechanical strength to penetrate the skin simulant and fully dissolve within 6 h. Drug release was sustained over 48 h in vitro, and platelet aggregation was evaluated using a simulated human platelet-rich plasma (PRP) model. Compared to clopidogrel solution, the microneedle patch maintained longer antiplatelet activity, with significant inhibition observed up to 72 h. These findings suggest that dissolvable microneedle patches may serve as a non-invasive and sustained delivery strategy for clopidogrel, potentially improving therapeutic consistency and patient compliance in stroke prophylaxis.

Polypropylene (PP) is a commonly used raw material for the production of 3D printing composite filament, which has many advantages, such as low density, insulation, chemical resistance, and environmental friendliness, but its mechanical strength is poor, which affects the comprehensive performance of the 3D printing PP model. In order to effectively improve the flexural strength of material-extrusion-based 3D printing (ME-3DP) PP model, this study investigated the influence of three printing parameters (infill rate, extrusion speed, platform temperature) on the flexural strength of the 3D printed PP model through the three-point support flexural test. The results show that the flexural strength of 3D printed PP model gradually increases with the increase of the infill rate, the decrease of the extrusion speed, and the increase of the platform temperature; the degree of influence of the three parameters on the flexural strength of the 3D printed PP model is as follows: infill rate ] extrusion speed ] platform temperature; the optimal combination of the printing parameters is as follows: infill rate (90%), extrusion speed (20 mm/s), and platform temperature (70°C). The flexural strength of the 3D printed PP model fabricated according to the optimal printing parameters is 41.7 MPa, which is the maximum value in the orthogonal experiment, verifying the reliability of the experiment results.

This research describes the development of a new sustainable and high-performance hybrid polymer matrix composite (HPMC) that reduces ecological impact by adding waste-based piassava fiver as a key reinforcing, sustainable, and biodegradable material. The composite contains Kevlar and waste based-piassava fibers in an epoxy matrix with nanosilicon dioxide particles (SiO2 NPs) to have the desired mechanical properties for uses in aerospace, railway cabins, structural frameworks, sports, medical equipment, and so on. Employing the hand lay-up method and compression moulding, sixlayered composites were made with different stacking sequences (A to O type) and SiO2 nanoparticle content (0, 0.5, 1, 1.5, and 2 wt.%). N-type stacking (KKPPKK) at 1.5 wt.% SiO2 NPs achieved the highest level of performance. The optimized composition produced impressive tensile strength (336 MPa), and flexural strength (381 MPa). Further, M-type composites with 1 wt.% SiO2 NPs had the highest impact strength of 263 J/m. Among all the combinations, the N-type composites absorbed less water, with 8.96% absorption, making them more useful in wet conditions. By incorporating waste-based piassava fiber and optimal nano SiO2 filler, this research creates a new way to achieve lightweight, durable, and environmentally responsible composite hybrid materials, positioning with the aims of sustainable engineering and waste valorization.

Natural rubber is a material, of vital importance, which is formed not only by the Hevea brasiliensis tree but also by various plant species (Carica papaya, Ficus carica, Taraxacum kok-saghyz, Parthenium argentatum). Amongst these, only the species Taraxacum kok-saghyz and Parthenium argentatum are explored as alternative sources of natural products. The goal of this article was to assess the screening of latex extracts, the determination of density, the determination of total solids, the determination of alkalinity, the determination of conductivity, the determination of total polyphenol content, the determination of total flavonoid content, the determination of antioxidant activity, the rubber extraction and the determination of rubber moisture. The screening result revealed the presence of proteins, amino acids, fatty acids, carboxylic acids, resins, alkaloids, phytosterols, terpenes, diterpenes, terpenoids, coumarins, polyphenols, flavonoids, saponins, steroids and the absence of catechins, glycosides, xanthoproteins, and anthocyanins. Following the determinations, the following values of the determined parameters were obtained: density 0.977 g mL−1, total solids 43.5%, alkalinity 0.53%, conductivity 210 μS cm−1, total polyphenols 349.7 μg GAE mL−1, total flavonoids 13.4 mg EC g−1, DPPH antioxidant activity 59.75%, ABTS antioxidant activity 511 μg TEmL−1, rubber mass 3.78% and rubber moisture 98.2%.

This paper proposes a new bridge reinforcement approach grounded in the technologically mature and extensively studied polymer mortar-HSSWM reinforcement technology. To verify the feasibility of this reinforcement method, this paper investigates the mechanical properties of high-strength steel wire mesh-polyurethane cement (HSSWM-PUC) composites through bond anchorage tests. The bond anchorage test of HSSWM with PUC was completed by setting wire diameter, longitudinal wire relative anchorage length, and transverse wire spacing as test variables. Some of the test results were verified by finite element analysis. The finite element model was established with the number of transverse wires, wire spacing, relative anchorage length, and wire diameter as variables. The experimental results were further studied and analyzed. The slip, ultimate load, and load-slip relationships of HSSWM and PUC under different variables were explored. Building upon this foundation, the variation rule between bond stress and slip of HSSWM-PUC composites is analyzed. Reducing the transverse wire spacing was found to increase the ability of the transverse wires to restrain the longitudinal wires. Meanwhile, with the increase of wire diameter, the bonding stress between HSSWM and PUC gradually decreases, whereas the bonding performance of PUC can be improved by appropriately reducing the ratio of adhesive powder.

This study investigates the properties and degradability of starch-based biofilms as sustainable, non-toxic, and biodegradable materials, emphasizing the effects of starch content and plasticizers on their performance. Starch biofilms are produced by casting a water solution that utilizes glycerol as a plasticizer and acetic acid as a co-plasticizer. A comprehensive analysis of the films was conducted, assessing various properties such as water absorption, swelling, water vapor transmission rate, water vapor permeability, environmental degradation, thermal decomposition, and tensile strength. The findings reveal that the addition of acetic acid significantly improves the physical properties of the starch biofilms, while the starch content predominantly influences their physical and mechanical characteristics. Notably, all film samples demonstrated excellent soil degradability, with substantial breakdown observed after just one month of burial in the soil garden. This research contributes to the field of biodegradable materials by showcasing the effectiveness of starch biofilms as an eco-friendly alternative, highlighting the role of plasticizers in enhancing their performance and confirming their environmental sustainability through rapid degradation in soil.

Phosphogypsum, as a by-product of the wet process phosphoric acid industry, is in urgent need of resource utilization due to the environmental risks caused by its massive accumulation; at the same time, the green recycling of used wind turbine blades (including glass fibers) is also a hotspot of global concern. In this study, a synergistic regenerative preparation method of environmentally friendly construction gypsum is proposed using phosphogypsum and recycled glass fibers from waste wind turbine blades as raw materials. The matrix material was prepared by mixing physically treated phosphorus building gypsum with natural building gypsum (8:2 ratio) and blended with recycled glass fibers of different lengths (0–5, 5–10, 10–15, 15–20 mm) and blending amounts (1.0%, 1.5%, 2.0%, 2.5%), and the effect on the performance of the gypsum was systematically analyzed. The results showed that the incorporation of glass fibers significantly reduced the slurry extension (maximum drop of 30 mm) and setting time (final setting time shortened by 115 s), but significantly improved the mechanical properties. The flexural strength reached 5.6 MPa when 15–20 mm glass fibers (2.0% doping) were doped, which was 51.35% higher than that of the blank control group; the compressive strength was raised to 11.3 MPa (24.17% higher) when 10–15 mm fibers (2.5% doping) were doped. The softening coefficient reached 0.67 at 15–20 mm fiber (dosing 1.5%), an enhancement of 32.37%. The microstructure shows that the glass fibers fill the pores inhibit crack extension through the bridging effect, and present a composite damage mode of fiber fracture and matrix debonding. This study provides a new way for the efficient synergistic utilization of phosphogypsum and waste wind turbine blades, with both environmental benefits and engineering application potential.