Developing wearable flexible biosensors with excellent electrical conductivity and outstanding flexibility simultaneously for disease diagnosis and health monitoring is a current hot topic in the ...field of sensor research. In this study, nitrogen-doped graphene (N-Gr) and gold nanoparticles (AuNPs) were successively deposited onto ITO-PET flexible conductive films by chemical deposition, and then a flexible electrochemical immunosensor with high sensitivity and selectivity was constructed for detecting depression markers by exploiting the high affinity between AuNPs and the sulfhydryl groups of depression marker (DM) antibody. Due to the composite of N-Gr, AuNPs and ITO-PET, the prepared flexible sensor can maintain a relatively stable electrical signal response regardless of the deformation such as spiral, rolling, and bending, without shedding or fracture of the N-Gr and AuNPs, and can also significantly amplify the electrochemical response signal of the immunosensor. Under optimized experimental conditions, the fabricated immunosensor showed good linearity over a wide range of 0.023–300.00 ng/mL with a low detection limit of 0.010 ng/mL (3σ, n = 5), when it was used for the determination of depression markers-human Apo-A4 in 100% whole serum samples. The flexibility of the constructed immunosensor and the stability and sensitivity of biomolecular analysis are expected to be further made into implantable depression marker in-situ monitoring probe with the help of micro-machining technology, which will develop a promising method for objective, efficient and accurate clinical diagnosis of depression.
Schematic representation of constructing AuNPs@N-Gr@ITO-PET-based electrochemical immunosensor for determination of apolipoprotein A4 (Apo-A4). Display omitted
•A highly sensitive and selective flexible immunosensor for determination of human apolipoprotein A4 (Apo-A4) has been fabricated.•The prepared AuNPs@N-Gr with large specific surface area, excellent electrical conductivity and outstanding flexibility can amplify the signal of immunosensor.•The proposed immunosensor can be used to sensitively and efficiently analyze apolipoprotein A4 (Apo-A4) in serum samples.•This method would provide a promising potential in early clinical screening and diagnosis of depression.
•Polydopamine for in-situ growth of three dimensional(3D) ZnO/Ag nanocomposites.•Raman hot spots of Ag on cluster-like ZnO nanorods for target molecules detection.•Enhanced photocatalysis by ...inhibited recombination of electron-hole pairs.•PET/pDA/ZnO/Ag SERS substrate with excellent sensitivity and reproducibility.
Surface-enhanced Raman scattering (SERS) spectroscopy as an effective method in sensitive detection applications has attracted more and more attentions recently. In this work, polydopamine was taken to achieve the modification of PET film surface for in-situ growth of three-dimensional (3D) ZnO/Ag nanocomposites. Ag nanoparticles on cluster-like ZnO nanorods surface were applied as Raman hot spots for target molecules detection. SEM, XPS, and XRD were used to characterize the microstructures and morphologies of 3D SERS substrates. pATP molecules were selected to measure the sensitivity, uniformity, and durability, the surface-enhanced enhancement mechanism of Raman scattering was analyzed by finite difference time domain (FDDT) simulation method. Malachite green (MG) was further used as the demonstrative pesticide residue, and the catalytic activity was studied by the deoxidization of 4-nitrophenol (4-NP). This work has indicated that SERS substrates exhibited the advantages of facile fabrication process, low cost, high sensitivity, good stability and excellent uniformity, which can be used for the rapid Raman enhanced spectroscopy analysis of environmental pollutants.
•Constant tensile experiments were carried out to test the elastic modulus values of PET films at temperatures of 25 °C (room temperature), 30 °C, 40 °C, 50 °C, 60 °C, 70 °C, 80 °C and 90 °C. The ...Wachtman model was improved, and the parameters of the experimental data were fitted, and a temperature-dependent elastic modulus model of PET films was established.•Based on the Kelvin-Voigt model and D’Alembert’s principle, the nonlinear vibration partial differential equation of the system is established and the Bubnov-Galerkin method is applied to discretize the partial differential equation to obtain the nonlinear vibration equation of state of the system.•Numerical analysis based on the 4th-order Runge-Kutta method was carried out to obtain the influence laws of parameters such as external excitation amplitude and frequency, drying hot air temperature, film width, and film movement speed on the nonlinear vibration characteristics of PET films, and to obtain the range of values of each parameter when the PET films are stably transported.
In order to improve the transport stability of roll-to-roll produced polyethylene terephthalate films (PET films) in high temperature environments, this paper investigates the nonlinear vibrational properties of moving PET films under a uniform temperature field by considering the temperature dependence of the elastic modulus. Firstly, constant tensile tests were conducted to test the elastic modulus values of PET films at different hot air temperatures, and the Wachtman model was improved to establish a temperature-dependent elastic modulus model for PET films. Secondly, based on the Kelvin-Voigt model, the nonlinear vibrational equilibrium differential equations of the system were established by applying the Bubnov-Galerkin method of discretization according to D’Alembert’s principle. Finally, numerical simulations based on the 4th-order Runge-Kutta method were carried out to analyze the effects of films width, external excitation frequency, external excitation amplitude, transfer velocity, ambient temperature, damping coefficient and viscoelasticity coefficient on the nonlinear vibration of the system. This provides a theoretical basis for the commissioning of stabilized transfer parameters for roll-to-roll production of PET films.
Understanding the troughs caused during a heat treatment process is important for ensuring process stability and product quality in roll-to-roll (R2R) productions methodology. The purpose of this ...study is to confirm the relationship between heat and troughs during a transport process of heating where heat is applied over a wide range of area. The temperature and tension applied to the web during the heated transport process were measured in the experimental analysis. Results showed that the web were stretched in the web transport direction during the heat transfer process. However, troughs did not occur because the experiment was conducted below the glass transition temperature. The comparison between the web temperature obtained in the experimental analysis with the one-dimensional thermal conduction simulation for the temperature distribution of the web are also conducted in this paper. This simulation was performed using a non-Fourier model that can be used on microscales. Simulation results show that when the temperature is gradually raised, the amount of thermal conduction is reduced during transportation of the web. The thermal conduction of ballistic phonon is smaller than that of the diffuse phonon when compared at same distance. Even though there were differences between the experimental values and the simulation results, this is because it ignores the heat transfer and radiant heat transfer.
10-point connector formed by two snap buttons Yang, Chang-Ming; Wu, Shu-Cing; Kao, Rally ...
2024 IEEE International Conference on Consumer Electronics (ICCE),
2024-Jan.-6
Conference Proceeding
Peer reviewed
With the rapid advancement of electronic textiles, the design and integration of connectors have emerged as pivotal challenges. This study emphasizes the development of a connection solution that ...amalgamates miniaturization, efficiency, and reliability, specifically tailored for Flexible Conductive Silicone Circuits. A diversified connection scheme is proposed, incorporating elements such as snaps, Pogo pins, and conductive hook-and-loop fasteners, thereby achieving an innovative and pragmatic design. Through meticulous manufacturing processes, including the utilization of hot-melt adhesive, PET films, conductive fabric, and other multilayer materials, a connection system with low impedance and commendable conductivity was successfully engineered. Impedance test outcomes have indicated that the resistance at each connection point is less than 0.7 ohms, substantiating its superior electrical properties. In terms of assembly, this research demonstrates the precise interconnection of the controller and conductive fabric circuit, ensured by metal pin technology, leading to connection stability. This solution not only furnishes appropriate connection technology for specific application scenarios but also opens new avenues and directions for connection design within the domain of electronic textiles.
Chitosan as an antibacterial agent and heparin as an anti-adhesive agent were alternatively deposited onto aminolyzed poly(ethylene terephthalate) (PET) films to construct anti-adhesive and ...antibacterial multilayer films. The contact-angle and UV data verified the progressive buildup of the multilayer film by alternate deposition of the polyelectrolytes. The properties of multilayer films were investigated by contact angle, atomic force microscopy (AFM), lateral force microscopy (LFM) and UV spectra. The results of initial adhesion of
Escherichia coli (E. coli) on PET substrates showed that the number of
E. coli adhered onto the control PET was in a much greater extent than onto the chitosan/heparin multilayer films, and the number of adhesive bacteria decreased with a decrease in assembly pH. The in vitro antibacterial test indicated that a multilayer of chitosan/heparin could kill the bacteria effectively. The number of viable bacteria decreased by 7% after 7
h in contact with the control PET films, but by 46–68% for the multilayer-modified PET films. Only 3–8% of the cells were viable for the multilayer-modified PET films after 24
h. It is interesting to find the assembly pH has a remarkable effect on the antibacterial property of the multilayer. The number of viable bacteria on the multilayer assembled at pH=3.8, 2.9 and 6.0 decreased by 68%, 58% and 46%, respectively. Such an easy processing and shape-independent method to prepare an anti-adhesive and antibacterial surface may have good potential for surface modification of cardiovascular devices.
The novelty of the study is that the ordering that occurs in a PET film under the action of SHI irradiation manifests itself as an increase in the integral intensity of intrinsic luminescence. The ...Urbach behaviour of the red shift of the absorption edge is used as a baseline for further analysis of experimental optical transmission spectra of PET films irradiated by swift heavy ions (SHI) previously published by the authors. Negative deviations of the experimental spectra from the Urbach baseline in the visible and UV parts of the spectrum are attributed to enhanced by SHI irradiation intrinsic luminescence. The observed dependence of the integral intensity of luminescence of irradiated PET films on the SHI fluence and ion charge provides further confirmation of the presence of SHI-induced ordering of the molecular structure in SHI latent tracks.
In 2018, the European Commission adopted the European Strategy for Plastics in a Circular Economy, which outlines key actions to reduce the negative impact of plastic pollution. The strategy aims to ...expand plastic recycling capacity and increase the proportion of recycled materials in plastic products and packaging. Using recycled plastic can save 50–60% energy compared to virgin plastic. Recycled PET can be used in the production of A-PET films, which are predominantly used in thermo-vacuum forming for food packaging. Storage conditions can influence the mechanical properties of polymer materials. This work presents changes in the mechanical properties of A-PET films after UV irradiation. An experimental investigation of the UV aging of A-PET films was conducted in a UV aging chamber. The specimens were exposed to a UV radiation dose rate of 2.45 W/m2 for 1, 2, 4, 8, 16, 24, 32, and 40 h. UV measurements were also taken on a sunny day to compare the acceleration of UV irradiation in the UV aging chamber. Mechanical tensile tests were performed on two different three-layer A-PET films (100% virgin and 50% recycled). The tensile strength and relative elongation of the A-PET films were determined, and the work required to break the film was calculated. The total consumed work was divided into the work needed for elastic and plastic deformations. A study of the UV aging of A-PET films confirmed a significant effect on the films, including a loss of plasticity even after brief exposure to solar irradiance. The results of the puncture impact test further confirmed the deterioration of the mechanical properties of A-PET material due to exposure to UV radiation, with a greater effect observed for the recycled material.
•Polyethylene terephthalate films synthesized by spray pyrolysis technique.•Al2O3:Tb3+ phosphors with luminescent properties were achieved.•Al2O3:Tb3+ powder embedded PET films were obtained.•A ...complete luminescence study was practiced.
The luminescent properties of Al2O3:Tb3+ powders embedded in polyethylene terephthalate (PET) films have been studied. Luminescent Al2O3:Tb3+ polycrystalline powders were synthesized by a simple evaporation method. The powder embedded films were obtained by the spray pyrolysis technique. The photoluminescence and cathodoluminescence emission spectra from these samples show, in both cases, luminescence peaks associated with transitions within the electronic energy levels of Tb3+ ions. The dominant peak is at 544nm corresponding to the 5D4 to 7F5 transition. In the case of the powder embedded films, the CIE coordinates depend on the excitation wavelength because there is a blue emission contribution from the PET host. UV–Vis% transmission measurements on these films show that they are transparent (∼80% and 95% T).
