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Passive cooling fabric that facilitates sweat‐wicking and evaporation is highly desirable for promoting human body's thermal comfort and reducing energy consumption. However, highly hydrophilic sweat‐wicking fabric fails to repel external fouling due to the contradiction between hydrophilicity and lyophobicity. Moreover, conventional passive cooling fabrics show limited evaporation capacity when they reach the adsorption limit in intense perspiration scenarios. Herein, a fouling‐proof cooling (FP‐Cool) fabric with an interactive functional structure design for highly‐efficient personal thermal regulation is proposed by constructing spatially distributed superoleophobic Janus channels on an optimized heat conductive superomniphobic fabric. The dominant superomniphobicity and superoleophobic Janus feature endow the outer FP‐Cool fabric with durable performance (up to 3000 cycles' abrasion) to repel oil/water‐based contaminations. The Janus channels rapidly pull sweat out of the inner fabric for efficient evaporation, ensuring a dry sense of skin. The FP‐Cool fabric preserves 40% higher thermal conductivity, and over 50% higher evaporation rate than conventional fabrics. In the sweat evaporation test, the FP‐Cool fabric shows up to 100% reduction in sweat gain ratio to cotton fabric. The concept would have implications for intelligent textiles design, and the synthesis strategy can be applied in various applications such as oil‐water separation and microfluidics control. [ABSTRACT FROM AUTHOR]

Selective-superwetting membranes possess controllable wettability and have great potential in the oil–water (OW) separation field. The electrospinning technique has advantages in fabricating nanofibrous materials with distinguishing features such as high porosity and large surface area. However, in recent years, there have been a few studies on preparing photoinduced superwetting membranes by electrospinning. In this study, an ultraviolet-driven selective-superwetting nanofibrous membrane was prepared by electrospinning poly-(vinylidene fluoride)-cohexafluoropropylene (PVDF-HFP) blended with fluorinated TiO2 nanoparticles. The wetting behavior of the membrane can be tuned between superhydrophobic/superoleophilic and superhydrophilic/underwater superoleophobic by two processes, ultraviolet (UV) irradiation, and heating, during which the water contact angle (WCA) fluctuates rapidly from 170 to 0° and back to 160°. The reliability of the controllable wettability was proven by a 15-cycle conversion test, and the nanofibrous membrane remained superhydrophobic thereafter. Our results have promising multipurpose applications as an effective and flexible solution to more complex oil–water mixtures in wastewater abatement. [ABSTRACT FROM AUTHOR]

Solid materials ubiquitously suffer from oil fouling in engineering applications. In this work, a facile and economical method was proposed to prepare a substrate-independent self-cleaning coating with remarkable oil repellency, which were realized by dints of the surface of nanocomposite structures with polar groups introduced by silica nanoparticles and polydopamine. The dip coating preparation process can be carried out in an ambient atmosphere without the use of hazardous reagents or complex equipment. The coating displays self-cleaning performance to detach the adhered oil after being immersed into water. The underwater contact angles were measured over 150° to various oils, further retaining stability in corrosive aqueous environments. Moreover, the coated glass shows resistance to water condensation, which can remain transparent after steaming or frosting, due to its hydrophilicity. The special wettability also endows the coated fabric with permselectivity to water and oil. Modified filter cotton was utilized to separate five kinds of oil/water mixtures. This study proposed a tried-and-true approach to realize oil repellency. It is anticipated that it could set a precedent for the design of self-cleaning or antifouling coatings. [ABSTRACT FROM AUTHOR]

The effect of the Zn/Mg ratio on microstructures, mechanical properties and corrosion performances of Al-Zn-Mg alloys was studied. Microstructures were characterized using the optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). Tensile tests, intergranular corrosion (IGC) and stress corrosion cracking (SCC) tests were conducted to study the properties. Microstructures results indicated that with the decrease of the Zn/Mg ratio, the recrystallization proportion and the fraction of second phase decreased, while the size of η' (MgZn2) phases in grain interior also significantly decreased. The number density of η' phases in grain interior increased and grain boundary precipitates developed discontinuous distribution with the decrease of the Zn/Mg ratio. These microstructures contributed to the significant improvement of the strength and corrosion resistance. The tensile strength and yield strength increased by 34.1% and 47.4%, respectively, with the Zn/Mg ratio decreased from 11.4 to 6.1. Calculating results indicated that the enhancement of strength mainly contributed from the solid-solution strengthening, grain-boundary strengthening and precipitation strengthening. The intergranular corrosion degree was greatly relieved and the stress corrosion sensitivity index decreased from 0.031 to 0.007 with the Zn/Mg ratio decreased from 11.4 to 6.1. [ABSTRACT FROM AUTHOR]

• A substrates-independent super-oleophobic/super-hydrophilic surface was prepared. • Reversible wettability transition can be achieved based on a solvent-responsive method within 10 s. • On-demand separation of heavy/light oil water mixtures and demulsification were achieved. • The as-prepared surfaces show a good recyclability and mechanochemical stability. Materials with common super-wettability are always restricted either by the pores fouling by oil (super-hydrophobicity/super-oleophilicity), or by the formation of hydration layer in advance (super-hydrophilicity/underwater super-oleophobicity) during oil water separation. To resolve this problem, super-oleophobic/super-hydrophilic surfaces were fabricated by introducing magnetic nanoparticles, short-chain fluorine groups and hydrophilic-induced units into the 2D or 3D substrates. Wettability formation mechanism was systematically investigated by combining theoretical calculation with characterization of surface micro-morphology and chemical composition. Surfaces with the uncommon super-wettability exhibited excellent anti-oil fouling ability, and can be directly used for oil water separation in way of "water removing". Moreover, a solvent-responsive wettability transition strategy was proposed, which can reversibly convert the super-oleophobic/super-hydrophilic surfaces into super-oleophilic/underoil super-hydrophobic surfaces within 10 s. Then, free light or heavy oil/water separation and demulsification of oil-in-water emulsions and water-in-oil emulsions were achieved through the switchable surface wettability toward water and oil. Furthermore, the super-wettability of as-prepared samples are almost unchanged even after the test of immersion in pH = 1 acid and pH = 14 alkali solution for 48 h and 100 cycles of successive cyclic compression. Hence, these unique advantages of the super-oleophobic/super-hydrophilic surfaces are promising for multitasking and highly efficient oil water separation and demulsification. [ABSTRACT FROM AUTHOR]

The effect of multi-stage aging heat treatments on the hardness, tensile strength, electrical conductance, and exfoliation corrosion (EXCO) resistance of the Al–Zn–Mg–Cu alloy has been studied through the Vickers hardness, tensile, conductivity, and EXCO testing combined with microstructure characterization using a transmission electron microscope. Experimental results demonstrated that multi-stage aging conditions could effectively enhance the localized corrosion resistance through a lower strength loss compared to T6 aging condition (120 °C/24 h). The designed four-step aging (FSA) treatments could improve the EXCO properties to PB degree along with the ultimate tensile strength and yield strength to 373 MPa and 324 MPa, respectively. The development trend of localized corrosion resistances has been further verified using electrochemical impedance spectroscopy and polarization dynamic curves. Microstructures results indicated that dense precipitates in matrix, discontinuous coarse precipitates on grain boundaries, and a proper precipitation free zone play an important role in balancing the strength and corrosion properties of the FSA aged alloy. • Multi-step aging treatment was designed in Al–Zn–Mg alloy. • The balance of strength and exfoliation corrosion were studied. • The effect of microstructure evolution on the corrosion resistance was studied. • The four-step aging treatment could improve the exfoliation corrosion resistance. • The designed four-step aging treatment could maintain higher yield strength. [ABSTRACT FROM AUTHOR]

The in-situ SEM observations and Line-scanning methods were used to observe the atomic concentration distribution and evolution of main elements in intermetallic phase at different solid solution temperatures. The results indicated that the atomic distribution of main elements in η (MgZn 2), S (Al 2 CuMg), Fe-containing (Al 7 Cu 2 Fe) intermetallic phases are parabolic through these phases, while the non-main elements uniformly distribute in matrix. The results of Differential Scanning Calorimetry (DSC) and Energy Dispersive Spectra (EDS) indicated that the Zn atoms dissolved into the matrix between 245 and 430 °C, under which the process of η phase transits to S phase occurred. The Cu element of S (Al 2 CuMg) phase has an obviously diffusion rate at 450 °C, while the Mg element has an obviously diffusion rate when the temperature is higher than 460 °C. Afterwards the atomic concentration dissolution was modelled by diffusion law, and the model results is corresponding to the linear rule, which agrees with the experiment results. • The in-situ SEM and Line-scanning methods were used to study the intermetallic. • The atomic distribution of elements in phases are parabolic. • The atomic concentration dissolution was modelled by diffusion law. • The diffusion temperature ranges of Zn, Cu and Mg atoms was studied. [ABSTRACT FROM AUTHOR]