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Higher education shoulders the task of cultivating high-level professionals with innovative spirit and practical ability. Undergraduate education plays a vital role as the beginning of higher education. However, the existing undergraduate teaching content is relatively outdated and the teaching mode is simple, making it difficult to stimulate students’ learning interest and improve their innovative practical ability. The scientific research project curriculum is rich in content and diverse in teaching forms, which can not only expand the teaching mode but also enrich and supplement professional knowledge. In this work, the teaching method of scientific research project curriculum is investigated in the investigated discipline - Material Science and Engineering. It is demonstrated that the introduction of scientific rlesearch project curriculum into undergraduate education or graduate education can help students improve their independent learning enthusiasm, professional practical skills, and innovative thinking abilities in the process of solving practical scientific research problems. Particularly, a project course about electrospun nanofibers is demonstrated to be a facile approach for achieving a comprehensive practice training for students. In a word scientific research project curriculum has proven to be a good teaching method for achieving “scientific research nurturing teaching”.

Bio‐based active food packaging materials have a high market demand. We use coaxial electrospinning technology to prepare core–shell structured nanofibers with sustained antibacterial and antioxidant properties. The fiber core layer was composed of gelatin and tea polyphenols, whereas tea polyphenols provide antibacterial and antioxidant properties; the fiber sheath was composed of pullulan polysaccharides with antioxidant properties. By using a scanning electron microscope, it can be seen that the diameter distribution of the prepared nanofibers was uniform and the surface is smooth; using a transmission electron microscope, it can be clearly seen that the nanofibers have a core–shell structure; Fourier Transform Infrared and X‐ray diffraction analysis indicate that the nanofibers have an amorphous structure; the 2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging shows that nanofibers have higher antioxidant properties with the addition of tea polyphenols; antibacterial test showed that nanofibers had obvious inhibitory effect on the growth of Staphylococcus aureus and Escherichia coli; and the nanofiber film dissolution test shows that nanofibers can be used as fast soluble active packaging. Finally, core–sheath‐structured nanofibers can serve as active packaging for instant food, possessing both rapid water solubility and excellent antibacterial and antioxidant activity, making water‐soluble nanofibers interesting applications in the field of food packaging. [ABSTRACT FROM AUTHOR]

Polymeric composites for manipulating the sustained release of an encapsulated active ingredient are highly sought after for many practical applications; particularly, water-insoluble polymers and core–shell structures are frequently explored to manipulate the release behaviors of drug molecules over an extended time period. In this study, electrospun core–shell nanostructures were utilized to develop a brand-new strategy to tailor the spatial distributions of both an insoluble polymer (ethylcellulose, EC) and soluble polymer (polyvinylpyrrolidone, PVP) within the nanofibers, thereby manipulating the extended-release behaviors of the loaded active ingredient, ferulic acid (FA). Scanning electron microscopy and transmission electron microscopy assessments revealed that all the prepared nanofibers had a linear morphology without beads or spindles, and those from the coaxial processes had an obvious core–shell structure. X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopic tests confirmed that FA had fine compatibility with EC and PVP, and presented in all the nanofibers in an amorphous state. In vitro dissolution tests indicated that the radical distributions of EC (decreasing from shell to core) and PVP (increasing from shell to core) were able to play their important role in manipulating the release behaviors of FA elaborately. On one hand, the core–shell nanofibers F3 had the advantages of homogeneous composite nanofibers F1 with a higher content of EC prepared from the shell solutions to inhibit the initial burst release and provide a longer time period of sustained release. On the other hand, F3 had the advantages of nanofibers F2 with a higher content of PVP prepared from the core solutions to inhibit the negative tailing-off release. The key element was the water permeation rates, controlled by the ratios of soluble and insoluble polymers. The new strategy based on core–shell structure paves a way for developing a wide variety of polymeric composites with heterogeneous distributions for realizing the desired functional performances. [ABSTRACT FROM AUTHOR]

Electrode materials have attracted considerable attention as pivotal components for high-performance supercapacitors (SCs). In recent years, electrospun carbon nanofibers (ECNFs) have emerged as promising candidates for SC electrodes owing to their distinctive one-dimensional morphology, adjustable internal pore size, and heteroatom doping capability. The design of ECNFs tailored for superior SC performance is currently a focal point of research. This review delineates the preparation and design strategies of ECNFs for SCs electrodes, encompassing both conceptual frameworks and practical considerations. First, it presents an overview of ECNF preparation techniques and modifications. Then, it focuses on the structural design of ECNFs for SC electrodes, encompassing functional group configuration, pore structure optimization, and composite structuring. Lastly, it examines prevailing challenges and outlines future research directions in this domain. This review is expected to serve as a foundation for future research endeavors on ECNFs, thereby promoting advancements in the realm of SC technology. [ABSTRACT FROM AUTHOR]

Personal protective equipment (PPE) has attracted more attention since the outbreak of the epidemic in 2019. Advanced nano techniques, such as electrospinning, can provide new routes for developing novel PPE. However, electrospun antibacterial PPE is not easily obtained. Fibers loaded with photosensitizers prepared using single-fluid electrospinning have a relatively low utilization rate due to the influence of embedding and their inadequate mechanical properties. For this study, monolithic nanofibers and core–shell nanofibers were prepared and compared. Monolithic F1 fibers comprising polyethylene oxide (PEO), poly(vinyl alcohol-co-ethylene) (PVA-co-PE), and the photo-antibacterial agent vitamin K3 (VK3) were created using a single-fluid blending process. Core–shell F2 nanofibers were prepared using coaxial electrospinning, in which the extensible material PEO was set as the core section, and a composite consisting of PEO, PVA-co-PE, and VK3 was set as the shell section. Both F1 and F2 fibers with the designed structural properties had an average diameter of approximately 1.0 μm, as determined using scanning electron microscopy and transmission electron microscopy. VK3 was amorphously dispersed within the polymeric matrices of F1 and F2 fibers in a compatible manner, as revealed using X-ray diffraction and Fourier transform infrared spectroscopy. Monolithic F1 fibers had a higher tensile strength of 2.917 ± 0.091 MPa, whereas the core–shell F2 fibers had a longer elongation with a break rate of 194.567 ± 0.091%. Photoreaction tests showed that, with their adjustment, core–shell F2 nanofibers could produce 0.222 μmol/L ·OH upon illumination. F2 fibers had slightly better antibacterial performance than F1 fibers, with inhibition zones of 1.361 ± 0.012 cm and 1.296 ± 0.022 cm for E. coli and S. aureus, respectively, but with less VK3. The intentional tailoring of the components and compositions of the core–shell nanostructures can improve the process–structure–performance relationship of electrospun nanofibers for potential sunlight-activated antibacterial PPE. [ABSTRACT FROM AUTHOR]

Core–shell nanostructures are powerful platforms for the development of novel nanoscale drug delivery systems with sustained drug release profiles. Coaxial electrospinning is facile and convenient for creating medicated core–shell nanostructures with elaborate designs with which the sustained-release behaviors of drug molecules can be intentionally adjusted. With resveratrol (RES) as a model for a poorly water-soluble drug and cellulose acetate (CA) and PVP as polymeric carriers, a brand-new electrospun core–shell nanostructure was fabricated in this study. The guest RES and the host CA molecules were designed to have a reverse gradient distribution within the core–shell nanostructures. Scanning electron microscope and transmission electron microscope evaluations verified that these nanofibers had linear morphologies, without beads or spindles, and an obvious core–shell double-chamber structure. The X-ray diffraction patterns and Fourier transform infrared spectroscopic results indicated that the involved components were highly compatible and presented in an amorphous molecular distribution state. In vitro dissolution tests verified that the new core–shell structures were able to prevent the initial burst release, extend the continuous-release time period, and reduce the negative tailing-off release effect, thus ensuring a better sustained-release profile than the traditional blended drug-loaded nanofibers. The mechanism underlying the influence of the new core–shell structure with an RES/CA reverse gradient distribution on the behaviors of RES release is proposed. Based on this proof-of-concept demonstration, a series of advanced functional nanomaterials can be similarly developed based on the gradient distributions of functional molecules within electrospun multi-chamber nanostructures. [ABSTRACT FROM AUTHOR]