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Sensing is a basic ability of smart structures. Self-sensing involves the structural material sensing itself. No device incorporation is needed, thus resulting in cost reduction, durability enhancement, sensing volume increase and absence of mechanical property diminution. Carbon fiber renders electrical conductivity to a composite material. The effect of strain/damage on the electrical conductivity enables self-sensing. This review addresses self-sensing in structural composite materials that contain carbon fiber reinforcement. The composites include polymer-matrix composites with continuous carbon fiber reinforcement (relevant to aircraft and other lightweight structures) and cement–matrix composites with short carbon fiber reinforcement (relevant to the civil infrastructure). The sensing mechanisms differ for these two types of composite materials, due to the difference in structures, which affects the electrical and electromechanical behaviors. For the polymer–matrix composites with continuous carbon fiber reinforcement, the longitudinal resistivity in the fiber direction decreases upon uniaxial tension, due to the fiber residual compressive stress reduction, while the through-thickness resistivity increases, due to the fiber waviness reduction; upon flexure, the tension surface resistance increases, because of the reduction in the current penetration from the surface, while the compression surface resistance decreases. These strain effects are reversible. The through-thickness resistance, oblique resistance and interlaminar interfacial resistivity increase irreversibly upon fiber fracture, delamination or subtle irreversible change in the microstructure. For the cement–matrix composites with short carbon fiber reinforcement, the resistivity increases upon tension, due to the fiber–matrix interface weakening, and decreases upon compression; upon flexure, the tension surface resistance increases, while the compression surface resistance decreases. Strain and damage cause reversible and irreversible resistance changes, respectively. The incorporation of carbon nanofiber or nanotube to these composites adds to the costs, while the sensing performance is improved marginally, if any. The self-sensing involves resistance or capacitance measurement. Strain and damage cause reversible and irreversible capacitance changes, respectively. The fringing electric field that bows out of the coplanar electrodes serves as a probe, with the capacitance decreased when the fringing field encounters an imperfection. For the cement-based materials, a conductive admixture is not required for capacitance-based self-sensing.

Immunotherapy has offered an alternative therapy method for cancer patients with metastatic tumors or who are not suitable for surgical resection. Different from traditional surgery, radiotherapy and chemotherapy, immunotherapy mainly restores the activity of the body’s own immune cells silenced in the tumor microenvironment to achieve anticancer therapy. Gene therapy which corrects abnormal expression of immune cells in tumor microenvironment by delivering exogenous genes to specific immune cells, is the most widely studied immunotherapy. Although most available gene delivery vectors are still viral vectors, the further application of viral vectors is still limited by the immunogenicity and mutagenesis. Based on this, cationic polymeric gene vectors with high flexibility, high feasibility, low cost and high safety have been widely used in gene delivery. The structural variability of polymers allows specific chemical modifications to be incorporated into polymer scaffolds to improve their physicochemical properties for more stable loading of genes or more targeted delivery to specific cells. In this review, we have summarized the structural characteristics and application potential in cancer immunotherapy of these polymeric gene vectors based on poly(L-lysine), poly(lactic-co-glycolic acid), polyethyleneimine, poly(amidoamine) and hydrogel system.

Vinylidene fluoride-trifluoroethylene copolymer films of molar ratio 70/30 with thickness of about 1 $\mu$m have been deposited from solution in ethyl methyl ketone to a glass substrate with an aluminum electrode by spin coating. The solution has been filtrated through a PTFE membrane filter with pore size 0.2 $\mu$m directly before spin coating or it has been used as is (unfiltrated). After deposition of a top electrode, the samples have been polarized by hysteresis loops with an electric field amplitude of about 100 V/$\mu$m. In samples, annealed at temperature 145${}^{\circ }$C for 3 h, a high remanent polarization of about 7.5 $\mu$C/cm² has been achieved, without significant differences between samples fabricated of filtrated or unfiltrated solution. Spherulitic lamella are growing in films fabricated of filtrated solution when they are heated above the melting temperature to 159${}^{\circ }$C for 3 min before the further annealing process at 145${}^{\circ }$C. These films show substantially lower remanent polarization below 4 $\mu$C/cm². Pyroelectric images recorded with a pyroelectric laser scanning microscope show that the spherulites have very small pyroelectric activity, i.e., the spherulites consist of flat-on lamella. In contrast, no spherulitic lamella are growing in films fabricated of unfiltrated solution heated above the melting temperature, melted and annealed under the same conditions. An explanation for this observation is that filtrating changes the structure of the copolymer in solution from polymer coil to rod. Copolymer rods deposited on a substrate will crystallize in flat-on lamella when heated above the melting temperature, in contrast to copolymer coils which crystallize in edge-on lamella.

The measurement of patients’ dosages of radiation caused by medical diagnostics continues to be challenging. A Cantor sequence photonic crystal structure using porous silicon doped with a polymer of polyvinyl alcohol, carbol fuchsin and crystal violet (DPV) is proposed. The influence rules of geometrical and optical parameters such as the radiation doses, number of periods, porosity of porous layers, incident angle and thickness of layers are investigated using MATLAB based on the transfer matrix method. The transmittance of the Cantor sequence of a defective photonic crystal sensor under different conditions is investigated to select the optimum conditions. The proposed system recorded the accepted sensitivity of 0.265nm/Gy, FoM of 6.5Gy${}^{-1}$, Q of 12,701, RS of $6\times 10^{-3}$ and LoD of $8\times 10^{-3}$ for gamma radiation. The suggested detector has simple design, accurate monitoring efficiency and immense potential for gamma radiation sensing.

By synthesizing new polymeric materials and combining them with growth factors or cells, new tissues and organs can potentially be created for use in drug testing-thereby potentially reducing animal and human testing- and to treat disease. Examples discussed include blood vessels, heart muscle, spinal cord repair, artifi cial skin, cartilage, and pancreas.

Membrane technologies are essential for water treatment, bioprocessing and chemical manufacturing. Stimuli-responsive membranes respond to changes in feed conditions (e.g., temperature, pH) or external stimuli (e.g., magnetic field, light) with a change in performance parameters (permeability, selectivity). This enables new functionalities such as tunable performance, self-cleaning and smart-valve behavior. Polymer self-assembly is a crucial tool for manufacturing such membranes using scalable methods, enabling easier commercialization. This review surveys approaches to impart stimuli responsive behavior to membrane filters using polymer self-assembly.

Photodynamic therapy (PDT) and photothermal therapy (PTT) are promising therapeutic methods for cancer treatment. However, both PDT and PTT have their own limitations. Thus, it is highly desirable to synthesize a single photosensitizer, which exhibits both PDT and PTT therapeutic performances. We have designed and synthesized a new porphyrin-based polymer (ZP-PT) by cross-linking fluoroporphyrins (ZnPor) and HS-terminated pentaerythritol tetra(3-mercaptopropionate) (PETMP). After being transformed into nanoparticles (ZP-PT NPs), they showed excellent water dispersity with the average size of about 100 nm. ZP-PT NPs could generate reactive oxygen species (ROS) and thermal energy under 635 nm laser irradiation. The singlet oxygen yield and the photothermal conversion efficiency (PCE) of ZP-PT NPs were calculated to be 0.46 and 27.07% respectively, which were apparently higher than that of ZnPor NPs. In addition, ZP-PT NPs exhibited higher colloidal stability and photostability than that of ZnPor NPs. All these results suggested that ZP-PT NPs had great potential in photodynamic and photothermal synergistic treatment of cancer.

In recent times, nanomaterials have attracted the interest of the scientific community with their superior applications when compared to bulk counterparts. Tungsten oxide (WO₃) nanoparticles (NPs) with their distinct properties such as electrochemical, photocatalytic, photoluminescent and gas sensing capabilities, are highly sought out. With these distinct properties, WO₃ NPs find significant application in device fabrication. This review provides an overview of the different synthesis methods, the properties and applications of tungsten oxide and doped tungsten oxide. The enhanced properties of WO₃ NPs with doping are also discussed in detail. In addition, this review also emphasizes on properties of WO₃ polymer nanocomposite and their applications in several areas of human enterprise.

Mechanisms of plasma-surface interaction are required to understand in order to control the reactions precisely. Recent progress in atmospheric pressure plasma provides to apply as a tool of sterilization of contaminated foodstuffs. To use the plasma with safety and optimization, the real time in situ detection of free radicals - in particular dangling bonds by using the electron-spin-resonance (ESR) technique has been developed because the free radical plays important roles for dominantly biological reactions. First, the kinetic analysis of free radicals on biological specimens such as fungal spores of Penicillium digitatum interacted with atomic oxygen generated plasma electric discharge. We have obtained information that the in situ real time ESR signal from the spores was observed and assignable to semiquinone radical with a g-value of around 2.004 and a line width of approximately 5G. The decay of the signal was correlated with a link to the inactivation of the fungal spore. Second, we have studied to detect chemical modification of edible meat after the irradiation. Using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF-MS) and ESR, signals give qualification results for chemical changes on edible liver meat. The in situ real-time measurements have proven to be a useful method to elucidate plasma-induced surface reactions on biological specimens.

Carbon nanomaterial (CNM)-reinforced polymer composite is broadly employed in emergent industrial needs due to advanced mechanical properties. In this research paper, a comparatively innovative integrated approach (SOA–CoCoSo) is proposed by using Principal Component Analysis (PCA)-based Combined Compromise Solution (CoCoSo) and Seagull Optimization Algorithm (SOA). This modified module is used in the drilling operation of zero-dimensional (0D) carbon nano-onion (CNO)-reinforced polymer (epoxy) composite. The desired machining performances, namely, surface roughness ($R_a$), thrust force (Th), and Torque (Tr), are optimized to improve the quality and productivity concerns. The control of process constraints, i.e. the wt.% of nanomaterial ($A$), spindle speed ($B$), and feed rate ($C$), was performed to achieve the desired objective value. The drilling experimentation was executed at three different levels of Box–Behnken Design (BBD). The objective function of PCA–CoCoSo was fed as input into the SOA. To acquire a better work efficiency, higher spindle speed, lower feed rate, and incremental wt.% of nanomaterial reinforcement are considered. The results demonstrated that the wt.% of CNO reinforcement and feed rate are the most influential factors for optimal machining performance results. The optimal constraints condition from the SOA–CoCoSo hybrid module is found at a combination of lower level of CNO wt.% (0.5wt.%) and feed rate (61mm/min) and high value of spindle speed (1500rpm). Also, the hybrid SOA–CoCoSo module shows a lesser amount of error percentage than the usual PCA–CoCoSo. The experiments were performed to confirm the feasibility of the suggested hybrid module for optimizing the varying machining parameters. The results indicated that the hybrid method is more efficient than the conventional method.

To ensure the safe operation of many safety critical structures such as nuclear plants, aircraft and oil pipelines, non-destructive imaging is employed using piezoelectric ultrasonic transducers. These sensors typically operate at a single frequency due to the restrictions imposed on their resonant behavior by the use of a single length scale in the design. To allow these transducers to transmit and receive more complex signals it would seem logical to use a range of length scales in the design so that a wide range of resonating frequencies will result. In this paper, we derive a mathematical model to predict the dynamics of an ultrasound transducer that achieves this range of length scales by adopting a fractal architecture. In fact, the device is modeled as a graph where the nodes represent segments of the piezoelectric and polymer materials. The electrical and mechanical fields that are contained within this graph are then expressed in terms of a finite element basis. The structure of the resulting discretized equations yields to a renormalization methodology which is used to derive expressions for the non-dimensionalized electrical impedance and the transmission and reception sensitivities. A comparison with a standard design shows some benefits of these fractal designs.

Thermal hysteresis and stability of agarose–water gelling systems were studied by the spectrophotometer for different concentrations at different temperatures. Gelation temperature depends on the concentration of agarose. With the increase in the concentration of agarose gelation temperature, strength of agarose increases too. With the increase in the concentration of polymer solvent–gel phase transition, gel melting happens at higher temperatures. The price of enthalpy was determined (150.0127 KC/mol). In gelation process, the phase separation is completed and in this process, the value of this $\mathrm{\Delta }t=t_{\mathrm{\text{melting}}}-t_{\mathrm{\text{gelation}}}$ equally increases.

Chemical approaches to creating new drug delivery systems and biomaterials are discussed. These delivery systems have been used to study how blood vessels grow and how different molecules affecting the brain behave. They have also been used in treatments ranging from schizophrenia to brain cancer.

Devices such as solar and fuel cells have been studied for many decades and noticeable improvements have been achieved. This paper proposes a Micro Photosynthetic Power Cell (μPSC) as an alternative energy-harvesting device based on photosynthesis of blue-green algae. The effect of important biodesign parameters on the performance of the device, such as no-load performance and voltage–current (V–I) characteristics, were studied. Open-circuit voltage as high as 993 mV was measured while a peak power of 175.37 μW was obtained under an external load of 850 Ω. The proposed μPSC device could produce a power density of 36.23 μW/cm², voltage density of 80 mV/cm² and current density of 93.38 μA/cm² under test conditions.

In this study, a novel method is introduced for preparing the poly (N-isopropylacrylamideco-methacrylic acid) (PNIPAM) hydrogel catalyst (PNMC-Ag) with embedded silver nanoparticles (Ag NPs), by employing in situ reduction of Ag+ in polymeric network. The prepared hydrogel catalyst exhibits both thermal and pH responsiveness, facilitating precise control of catalytic efficiency in reducing pollutants such as 4-nitrophenol (4-NP) under varying environmental conditions. The embedded Ag NPs demonstrate remarkable stability against self-aggregation due to their confinement within the polymeric network, thus maintaining their exceptional catalytic performance over time. Leveraging the dual-responsive nature of the PNMC-Ag catalyst, tunable catalytic activity can be achieved by adjusting the temperature and pH of the reaction environment. Specifically, the Ag NPs-hydrogel catalyst exhibits high catalytic activity (21 min, 98.5%) in low-temperature ($T$< 32°C) at neutral pH and alkaline (pH = 9) conditions at room temperature, while its activity is attenuated in high-temperature ($T$> 32°C) at neutral pH or acidic (pH $\le$4) environments at room temperature owing to the hydrogel’s thermal and pH-responsive characteristics. This distinctive feature enables precise control over the catalytic reaction, offering an effective approach for the removal of 4-NP from wastewater using a noble-metal-containing stimuli-responsive hydrogel (SRH) catalyst. Overall, this work represents a significant step towards the development of intelligent catalytic materials with superior environmental remediation capabilities.

The scaling expression for fractional Brownian modeled linear polymer chains was obtained both theoretically and numerically. Through the probability distribution of fractional Brownian paths, the scaling was found out to be 〈R²〉 ~ N^2H, where R is the end-to-end distance of the polymer chain, N is the number of monomer units and H is the Hurst parameter. Numerical data was generated through the use of Monte Carlo simulation implementing the Metropolis algorithm. Results show good agreement between numerical and theoretical scaling constants after some parameter optimization. The probability distribution confirmed the Gaussian nature of fractional Brownian motion and the behavior is not affected by varying values of the Hurst parameter and of the number of monomer units.

The carbon nanotubes grafted methylene blue molecularly imprinted polymers (CNT-MB-MIPs) were prepared by grafting aminated carbon nanotubes (CNTs) and copolymerized in the presence of template molecules methylene blue (MB), functional monomers, crosslinkers, and initiators. The results from structural analyses indicate that CNTs were successfully grafted onto the molecularly imprinted polymers (MIPs). The adsorption experiments showed that the adsorption capacity can be affected by grafting CNTs. The adsorption capacity of CNT-MB-MIPs on MB can reach 2793mgg${}^{-1}$ while the initial concentration of MB was 12gL${}^{-1}$, which was higher than that of MB molecularly imprinted polymers (MB-MIPs). Meanwhile, compared with MB-MIPs, CNT-MB-MIPs had a lower adsorption capacity for iron ions, indicating that CNT-MB-MIPs could inhibit the adsorption of iron ions. Adsorption kinetics study showed that the adsorption mechanism of the polymer for MB was in good agreement with the quasi-second-order kinetics model ($R^2=0.9978$) and the adsorption mechanism for iron ions was also in good agreement with the Bangham kinetics model ($R^2=0.9475$). The adsorption isotherm showed that the adsorption process of the two adsorbents was mainly monolayer chemisorption. The remarkable adsorption capacity of CNT-MB-MIPs may be due to the enlargement of adsorption sites on MIPs surface by CNT-NH₂ grafting. At the same time, it can inhibit the adsorption of iron ions, because part of the carboxyl groups in CNT-MB-MIPs are bonded by CNTs, led to few carboxyl groups sites left for adsorbing iron ions, thereby the complex between carboxyl groups and iron ions were inhibited.

Polymer nanocomposite is commonly used to develop structural components of space, aircraft, biomedical, sensor, automobile, and battery sector applications. It remarkably substitutes the heavyweight metallic and nonmetallic engineering materials. The machining principles of polymer nanocomposites are intensely different and complex from traditional metals and alloys. The nonhomogeneity, abrasive, and anisotropic nature differs its machining aspect from conventional metallic materials. This investigation aims to execute the CNC drilling of modified nanocomposite using Graphene–carbon (G-C) @ epoxy matrix. The process constraints, namely, cutting speed (S), feed (F), and wt.% of graphene oxide (GO) vary up to three levels and are designed according to the response surface methodology (RSM) array. The nonlinear model is created to predict surface roughness (Ra) and delamination (Fd) on regression analysis. It has been found that the average error for Ra is 0.94% and for Fd it is 3.27%, which is acceptable in model predictions. The metaheuristics-based evolutionary Dragonfly algorithm (DA) evaluated the optimal parametric condition. The optimal setting prediction for the DA is observed as cutting speed (S)-37.68m/min, feed (F)-80mm/min, and wt.% of graphene oxide (GO)-1%. This algorithm demonstrates a higher application potential than the previous efforts in controlling Ra and Fd values. Both the drilling response values are found to be minimized when the cutting speed increases and the feed decreases. The best fitness value for the DA is 1.626 for surface roughness and 5.086 for delamination. This study agreed with the prediction model’s outcomes and the process parameters’ optimal condition. The defects generated during the sample drilling, such as fiber pull out, uncut/burr, and fiber breakage, were examined using FE-SEM analysis. The optimal findings of the DA module significantly controlled the damages during machining.

Polymer nanocomposites (PNCs) are functional hybrids lying at the interface of organic and inorganic realm, whose high versatility offers numerous possibilities to develop tailor-made materials with advanced material behaviors. Accordingly, a considerate combination of optically effective additive and particle-stabilizing polymer often opens up unique design possibilities, thereby offering momentous lead in creating advanced functional materials for targeted techno-commercial applications. Accordingly, optically effective nanofillers characterized by particle size and dielectric constant of the surrounding medium-dependent surface plasmon resonance effects may induce entirely new optical functionalities (UV and visible light absorption, optical dichroism, spectral manipulation, photonic emission and so forth) in the polymeric host. Herein, we discuss the major causative factors, which enable nanostructured materials to exhibit unique properties, general introduction to nanotechnology-enabled polymer-based nanocomposites and present a comprehensive review on functional properties and related applications of PNCs, with special emphasis on optical functionalities (photonic absorption encompassing UV shielding, color switching and refractive index engineering and photonic emission covering photoluminescence and spectral manipulations). This review also sheds light on the effect of nature of filler, filler morphology, filler size and filler composition and dispersion homogeneity on optical behaviors of polymer nanocomposites.

The probability density for the area A enclosed by a polymer loop in crossed electric-magnetic fields is evaluated using the Hida-Streit formulation. In this approach, the many possible conformations of the polymer, x(v) and y(v), are represented by paths and are parametrized in terms Brownian motion. When the magnetic field is switched off, results agree with the works of Khandekar and Wiegel⁵