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A new composite gel material was obtained by blending polyvinyl alcohol (PVA) aqueous solution with sodium alginate (SA), sodium carboxymethyl cellulose (CMC-Na), waterborne polyurethane (WPU), and polyvinylpyrrolidone (PVP). Titanium dioxide nanoparticles (nTi[O.sub.2]) were doped as an antibacterial agent. The liquid composite could to form a transparent protective gel membrane. The microstructure of the gel membrane was observed via scanning electron microscopy, and the intermolecular interaction was investigated by total reflection infrared spectroscopy. The results demonstrated a homogeneous phase and significant hydrogen bonding between chain segments. The best results indicated that the equilibrium swelling rate increased from 147% to 170%, the 3-h water vapor transmission rate increased from 279.41 g/[m.sup.2]*day to 374.75 g/[m.sup.2]*day, and the water contact angle increased from 16.8 (0) to 60.7[degrees], relative to the PVA substrate. The properties of this composite gel material suggest possible biomedical usage, particularly in skin and wound protection scenarios. Highlights * A novel gel film-forming material consisting of a viscous liquid is prepared. * Adding polysaccharides modifiers resulted in significant improvements of the performance. * The bacteriostatic and antihemorrhagic properties are introduced to the material. * Low-irritating materials were used to prepare the gel material. KEYWORDS antibacterial performance, gel composite material, polyvinyl alcohol, sodium alginate, tensile strength, wound protection, 1 | INTRODUCTION Several polymers, like nitrocellulose, chitosan, and polyacrylic acid, can be dispersed in solvents to produce polymer solutions, which can then be applied to the skin to form [...]

In order to evaluate the effect of rare earth Y2O3 on the wear and corrosion properties of WC–Ni composite coatings, X-ray diffraction, scanning electron microscopy(SEM), electrochemical polarization curve, electrochemical impedance spectroscopy (EIS), and friction and wear tests were used to analyze the metallographic structure, corrosion characteristics in simulated seawater and friction and wear principle of the composite coatings. Results of SEM revealed that the microstructure of the Y2O3 added coatings was refined with the grains changing smaller and the impurity disappearing. The EIS results proved that the addition of Y2O3 brought a positive influence on the corrosion resistance by reducing the capacitance and increasing the R f and R c. The hardness of the coatings with Y2O3 addition tends to be smooth without wild fluctuation, and the coating with 0.5 wt% Y2O3 owned the hardness values reaching 850 HV. With the addition of rare earth elements, the coefficient of fiction values decreased, reaching the lowest (0.3418) at the content of Y2O3 of 0.5 wt%. The surface of the coating without Y2O3 appears grooved due to the abrasive wear; the coatings with Y2O3 did not suffer serious wear and tear. The coating with 0.5 wt% Y2O3 exhibited the best corrosion resistance and wear resistance properties in all the specimens.

In this paper, four kinds of coatings Ni + 30% WC, Ni + 15% WC, Ni, and Co are prepared on EH40 steel by laser cladding technology. Electrochemical experiment tests at a simulating low-temperature (–40°C) environment in 0.5 mol·L−1 hydrochloric acid (HCl) solution and 3.5 wt% NaCl solution were conducted, and the polarization curve and electrochemical impedance spectroscopy (EIS) impedance spectrum were obtained. The results show that the Ni + 15% WC coating has the smallest corrosion current and 0.5 mol·L−1 HCl solution and 3.5 wt% NaCl solution have the maximum polarization resistance and impedance arc. Coatings will be treated in a 0.5 mol·L−1 HCl solution and 3.5 wt% NaCl solution at –40°C immersion for 30 days; finally, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used for test passivation films of Ni + 15% WC samples and sample surface morphology after corrosion. XPS results show that Fe, Mo, and Ni elements can form metal oxides in the 0.5 mol·L−1 HCl solution, and Cr, Fe, Mo, Ni, and W elements can form metal oxides in the 3.5 wt% NaCl solution. SEM results display that relatively severe corrosion appeared on the substrate near tungsten carbide in a 0.5 mol·L−1 HCl solution, and coating will be corroded form inside of the coating owing to the corrosive solution will penetrate the substrate. In 3.5 wt% NaCl solution, severe corrosion of the substrate has not been observed; however, the binding part has been obviously corroded.

To investigate the corrosion behavior of WC–Co composite coating, plasma transferred arc (PTA) welding was applied to prepare WC–Co coating on hull steel EH40 for achieving good metallurgical bonding. The phases of coatings were mainly composed of WC particles, solid solution γ-Co, Fe3Ni2, SiO2 and Mo2C. After electrochemical test, it can be concluded that Co-based coating with 45% WC content has better corrosion resistance in low temperature marine environment for obtaining denser oxide film. Through X-ray photo electron spectroscopy (XPS) analysis, the main corrosion products of immersion were Co(OH)2 and Co3O4. These corrosion products aggregate to form a stable corrosion product film, which plays some protective role for the coating. Hard particle WC is also partially oxidized to WO3. The pitting hole of 60% WC is the most serious. Pitting corrosion is easy to occur at the interface defects.

When illuminated by a resonant laser, noble metal nanoparticles immersed in liquids can efficiently produce a huge amount of heat and rapidly vaporize surrounding liquid, leading to the nucleation of plasmonic bubbles. Plasmonic bubbles are gaining increasing attention and emerged in numerous applications due to their unique properties and excellent controllability, such as microfabrication, micromanipulation, robot propulsion, molecule enrichment, and clinical therapies. In this review paper, the research progress of plasmonic bubbles in the past decade is summarized, including the plasmonic effect‐induced heat generation, experimental methods of plasmonic bubble observation, growth dynamics of plasmonic bubbles, approaches of optomechanical energy conversion via plasmonic bubbles, as well as their applications. This work provides a comprehensive understanding of the state of the art in the field and inspires researchers to explore more promising applications of plasmonic bubbles in different fields, like biology, microfluidics, and micromanufacturing. [ABSTRACT FROM AUTHOR]