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The paper investigates overview of construction process of a 1 MW class floating photovoltaic (PV) generation structural system fabricated with fiber reinforced polymer (FRP) members. The floating PV generation system consists of unit structures linked by a hinge type connection of which the effect of bending moment between the unit structures, induced by the unstable movement of the water surface, was minimized. Moreover, the unit structures were classified into three types of structures by combining the floating PV generation system and pontoon bridges, which are constructed to install the electrical equipment and a route of movement for workers. The structural safety of the connection system among the unit structures and/or the mooring system is confirmed by referring to the relevant design codes. In addition, structural analysis using the finite element method was performed to ensure the safety of the floating PV generation structure, and commercial viability evaluation was performed based on the construction cost. The FRP member shows superior performance in construction and cost effectiveness in a floating PV generation system.

This paper presents an investigation conducted on repairing damaged Reinforced Concrete (RC) beams with a large rectangular web opening using externally bonded plates. Carbon Fiber Reinforced Polymer (CFRP) and steel plates were used as repair materials with two types of configuration - hexagonal and rectangular - for each material. The beams contain a rectangular web opening at one of the shear spans. The externally bonded CFRP sheet and steel plate were found to be effective in repairing RC beams with a large rectangular web opening. The results showed that CFRP plates perform better than steel plates and that the rectangular configuration is better than the hexagonal one.

The paper aims to develop improved acoustic-based structural health monitoring (SHM) and nondestructive evaluation (NDE) techniques, which provide the waves directivity emitted by the angle beam wedge actuators in thin-walled structures made of plastic materials and polymeric composites. Our investigation includes the dispersive analysis of the waves that can be excited in the studied plastic panel. Its results allowed to find two kinds of generated acoustic waves—anti-symmetric Lamb waves (A0) and shear horizontally polarized SH waves (SS0). The bounds of the chosen frequency range for the experimental and numerical studies were accepted as a compromise between the desire to obtain a high defect resolution by generating short waves, their adjustable directivity, and maximum propagation length. The finite element model for the transducer was built by using the results of an actuator structure experimental study. The frequency response functions for the actuator current and oscillation amplitude of the footprint surface demonstrated good agreement. The found eigenfrequencies of the actuator’s structure were used for the numerical and experimental study of the Lamb and SH wave generation and propagation in a thin-walled plastic panel. Our results convincingly demonstrated the satisfactory directivity of the actuated waves at their excitation on the frequencies that corresponded to the natural modes of the actuator oscillation. The authors assume that an efficient use of the proposed technique for other analyzed quasi-isotropic materials and applied actuators can be provided by preliminary research using a similar approach and methods presented in this article.

High-strength antifriction polymeric carbon-fiber-reinforced plastics (carbon plastics) of FUT and UPFS types were developed for facilitating operation of friction assemblies of oil-and-gas and power engineering equipment. The strength and wear resistance of these materials were improved by modifying the chemical composition of the phenolic binder, by electrochemical treatment (ECT) of the carbon fabric surface, by changing the nanostructure of the carbon fibers, and by inserting disperse particles of micromodifiers, i.e., of metals (babbitt, nickel, etc.), into the carbon plastics.

High-strength antifriction polymeric carbon plastics of UGET and FUT types and their modifications UGET-TN, FUT-B, UGET-MF, and FUT-MF as well as a new heat-resistant antifriction carbon plastic of UPFS type were developed for oil and gas and power machine making. These materials are superior to traditional polymeric antifriction materials in strength and wear resistance.

In today's world, bioplastics are becoming increasingly prominent owing mainly to scarcity of oil, increase in the cost of petroleum-based commodities, and growing environmental concerns with the dumping of non-biodegradable plastics in landfills. This book summarizes the field of bioplastics by illustrating how they form a unique class of research area that integrates pure and applied sciences such as chemistry, engineering and materials science, to initate solutions. Compelling science demystics this complex and often ambiguous branch of study for benefit of all those concerned with bioplastics.

Ocular drug delivery has been a major challenge for clinical pharmacologists and biomaterial scientists due to intricate and unique anatomical and physiological barriers in the eye. The critical requirement varies from anterior and posterior ocular segments from a drug delivery perspective. Recently, many new drugs with special formulations have been introduced for targeted delivery with modified methods and routes of drug administration to improve drug delivery efficacy. Current developments in nanoformulations of drug carrier systems have become a promising attribute to enhance drug retention/permeation and prolong drug release in ocular tissue. Biodegradable polymers have been explored as the base polymers to prepare nanocarriers for encasing existing drugs to enhance the therapeutic effect with better tissue adherence, prolonged drug action, improved bioavailability, decreased toxicity, and targeted delivery in eye. In this review, we summarized recent studies on sustained ocular drug/gene delivery and emphasized on the nanocarriers made by biodegradable polymers such as liposome, poly lactic-co-glycolic acid (PLGA), chitosan, and gelatin. Moreover, we discussed the bio-distribution of these nanocarriers in the ocular tissue and their therapeutic applications in various ocular diseases.

Electronic sensor foils only 2 μm thick are extremely light, 27-fold lighter than office paper, durable and flexible and conform to curvilinear surfaces for many innovative applications. Feather-light unbreakable plastic electronics Flexible electronics is emerging as a mainstream technology for smart, mobile, wearable devices and also for biomedical applications. Kaltenbrunner et al . break new ground by fabricating light-as-a-feather virtually imperceptible and unbreakable electronic foils that can conform to any desired shape. The foils consist of organic transistors with an ultra-dense oxide gate dielectric, itself only a few nanometres thick, deposited on ultra-lightweight plastic films, for an overall thickness of just two micrometres. They can withstand repeated severe bending and stretching, can crumple like paper, and work at elevated temperatures and in wet environments. The authors demonstrate that the flexible electronic foil can act as a tactile sensor on a model of the upper human jaw, illustrating the potential for this technology in health care and monitoring. Electronic devices have advanced from their heavy, bulky origins to become smart, mobile appliances. Nevertheless, they remain rigid, which precludes their intimate integration into everyday life. Flexible, textile and stretchable electronics are emerging research areas and may yield mainstream technologies 1 , 2 , 3 . Rollable and unbreakable backplanes with amorphous silicon field-effect transistors on steel substrates only 3 μm thick have been demonstrated 4 . On polymer substrates, bending radii of 0.1 mm have been achieved in flexible electronic devices 5 , 6 , 7 . Concurrently, the need for compliant electronics that can not only be flexed but also conform to three-dimensional shapes has emerged 3 . Approaches include the transfer of ultrathin polyimide layers encapsulating silicon CMOS circuits onto pre-stretched elastomers 8 , the use of conductive elastomers integrated with organic field-effect transistors (OFETs) on polyimide islands 9 , and fabrication of OFETs and gold interconnects on elastic substrates 10 to realize pressure, temperature and optical sensors 11 , 12 , 13 , 14 . Here we present a platform that makes electronics both virtually unbreakable 4 and imperceptible. Fabricated directly on ultrathin (1 μm) polymer foils, our electronic circuits are light (3 g m −2 ) and ultraflexible and conform to their ambient, dynamic environment. Organic transistors with an ultra-dense oxide gate dielectric a few nanometres thick formed at room temperature enable sophisticated large-area electronic foils with unprecedented mechanical and environmental stability: they withstand repeated bending to radii of 5 μm and less, can be crumpled like paper, accommodate stretching up to 230% on prestrained elastomers, and can be operated at high temperatures and in aqueous environments. Because manufacturing costs of organic electronics are potentially low, imperceptible electronic foils may be as common in the future as plastic wrap is today. Applications include matrix-addressed tactile sensor foils for health care and monitoring, thin-film heaters, temperature and infrared sensors, displays 15 , and organic solar cells 16 .

This review presents a perspective on the research trends and solutions from recent years in the domain of antimicrobial packaging materials. The antibacterial, antifungal, and antioxidant activities can be induced by the main polymer used for packaging or by addition of various components from natural agents (bacteriocins, essential oils, natural extracts, etc.) to synthetic agents, both organic and inorganic (Ag, ZnO, TiO2 nanoparticles, synthetic antibiotics etc.). The general trend for the packaging evolution is from the inert and polluting plastic waste to the antimicrobial active, biodegradable or edible, biopolymer film packaging. Like in many domains this transition is an evolution rather than a revolution, and changes are coming in small steps. Changing the public perception and industry focus on the antimicrobial packaging solutions will enhance the shelf life and provide healthier food, thus diminishing the waste of agricultural resources, but will also reduce the plastic pollution generated by humankind as most new polymers used for packaging are from renewable sources and are biodegradable. Polysaccharides (like chitosan, cellulose and derivatives, starch etc.), lipids and proteins (from vegetal or animal origin), and some other specific biopolymers (like polylactic acid or polyvinyl alcohol) have been used as single component or in blends to obtain antimicrobial packaging materials. Where the package’s antimicrobial and antioxidant activities need a larger spectrum or a boost, certain active substances are embedded, encapsulated, coated, grafted into or onto the polymeric film. This review tries to cover the latest updates on the antimicrobial packaging, edible or not, using as support traditional and new polymers, with emphasis on natural compounds.