A method of forming a heat exchanger tube, particularly suited for condensing applications, contemplates cold-rolling a metallic strip to emboss a hydrophobic surface texture, to thereby form an embossed surface on the metallic strip. The method includes roll forming the metallic strip to a tubular shape, with the embossed surface on the exterior of the tubular shape, and welding the edges of the roll-formed strip to form a heat exchanger tube. Cold-rolling to emboss a hydrophobic surface texture exhibiting a contact angle of at least about 75° is contemplated, with processing including heat-treatment to minimize degradation of the hydrophobic surface texture, and roll-forming to avoid deformation of the hydrophobic surface texture,

A coating including a relatively thin visible-absorptive layer atop a relatively thick non-absorptive, solar-scattering underlayer. The thin top layer enables efficient absorption of appropriate visible wavelengths to show specific colors, and minimizes absorption in the infrared radiation in sunlight due to its relatively small thickness. Meanwhile, the bottom layer maximizes the backscattering of infrared light without absorption to reduce solar heating.

The present invention provides a radiative cooling structure that can be fabricated using solution-based processes and offer great IR-selectivity referring to low absorptivity within solar spectrum and high emissivity within the atmosphere transmission window (8-13 microns) for daytime radiative cooling. This structure includes a reflective layer, a ceramic IR-selectively emissive layer and a ceramic emission boosting layer, and the ceramic emission boosting layer is able to boost the overall emissivity of the radiative cooling structure within the atmosphere transmission windows and avoid infrared emission outside the atmosphere transmission window. The IR-selectivity contributes to larger temperature reduction, especially in high humidity area.

An ordered, 3-dimensional, micro-scale, open-cellular truss structure including interconnected hollow polymer tubes. The hollow micro-truss structure separates two fluid volumes which can be independently pressurized or depressurized to control flow, or materials properties, or both. Applications for this invention include deployable structures, inflatable structures, flow control, and vented padding.

The present disclosure describes a strategy to create self-healing, slippery liquid-infused porous surfaces. Roughened (e.g., porous) surfaces can be utilized to lock in place a lubricating fluid, referred to herein as Liquid B to repel a wide range of materials, referred to herein as Object A (Solid A or Liquid A). Slippery liquid-infused porous surfaces outperforms other conventional surfaces in its capability to repel various simple and complex liquids (water, hydrocarbons, crude oil and blood), maintain low-contact-angle hysteresis (<2.5°), quickly restore liquid-repellency after physical damage (within 0.1-1 s), resist ice, microorganisms and insects adhesion, and function at high pressures (up to at least 690 atm). Some exemplary application where slippery liquid-infused porous surfaces will be useful include energy-efficient fluid handling and transportation, optical sensing, medicine, and as self-cleaning, and anti-fouling materials operating in extreme environments.

A method of manufacturing a laminate includes: forming a preprocessing coating on a surface of a substrate having insulating properties by accelerating the powdered material together with gas and spraying the powdered material in a solid phase onto the surface of the substrate, the powdered material including aluminum or an aluminum alloy as a main component; and forming a heat-treated coating having a surface with irregular asperities by heating a preprocessing laminate including the substrate and the preprocessing coating formed on the surface of the substrate.

Various aspects as described herein are directed to a radiative cooling device and method for cooling an object. As consistent with one or more embodiments, a radiative cooling device includes a solar spectrum reflecting structure configured and arranged to suppress light modes, and a thermally-emissive structure configured and arranged to facilitate thermally-generated electromagnetic emissions from the object and in mid-infrared (IR) wavelengths.

An apparatus includes a heat exchanger configured to transfer heat to a fluid and to absorb heat from the fluid as the fluid flows between a warm end and a cold end of a cryocooler. The heat exchanger includes at least one section having a substrate of at least one allotropic form of carbon and a layer of nanoparticles on or over the substrate. The heat exchanger could include multiple sections, and each section could include one of multiple substrates and one of multiple layers of nanoparticles. The heat exchanger can further include pores through the multiple sections of the heat exchanger, where the pores are configured to allow the fluid to flow through the heat exchanger and to contact the substrates and the layers of nanoparticles. The nanoparticles could include at least one lanthanide element or alloy, and the substrate could include carbon nanotubes or graphene.

The invention provides metal members having liquid-repellent and corrosion-resistant surfaces, without the need for SAM surface treatment. A metal member of the disclosure has a porous surface, having the porous surface directly covered by a hydrocarbon-based oil comprising zinc dialkyldithiophosphate (ZnDTP). The porous surface may be an oxidized surface, and especially an anodized surface. The metal member may be a member of Al, Ti, Fe or Mg, or an alloy of any of these metals, or stainless steel. The concentration of the zinc dialkyldithiophosphate (ZnDTP) may be 0.1 mass % to 30.0 mass % with respect to the hydrocarbon-based oil.

A heat exchange apparatus, and method of forming the apparatus, are disclosed. The apparatus includes a thermally conductive substrate with a metal microlattice structure adhered to the thermally conductive substrate and in thermal communication with the thermally conductive substrate, the metal microlattice structure comprising a region containing an electroless metal. A method of making the apparatus includes forming a polymer lattice, applying the polymer lattice to a thermally conductive substrate, forming an electroless plated metal layer on the polymer lattice, forming an electroplated metal layer on the electroless metal layer, and forming a metal microlattice of the electroless metal layer and the electroplated metal layer.