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This research explores Microwave Plasma Chemical Vapor Deposition (MPCVD) for depositing diamond films on steel alloys (316L, 4140, and 1018) with a vanadium carbide interlayer to enhance adhesion and compatibility. The study reveals that a soft vanadium carbide interlayer and the FCC lattice match lead to a Ta-C film. The results of the graphite inhibition and diamond deposition varied with the steel alloy underlayer composition. In the 316L steel alloy, we successfully formed a thick, compressive strain-induced, sp3-bonded tetrahedral amorphous carbon layer without graphite. The findings have wide-ranging applications in environments demanding high durability and thermal conductivity. 

Abstract By virtue of their native structures, tubulin dimers are protein building blocks that are naturally preprogrammed to assemble into microtubules (MTs), which are cytoskeletal polymers. Here, polycation‐directed (i.e., electrostatically tunable) assembly of tubulins is demonstrated by conformational changes to the tubulin protofilament in longitudinal and lateral directions, creating tubulin double helices and various tubular architectures. Synchrotron small‐angle X‐ray scattering and transmission electron microscopy reveal a remarkable range of nanoscale assembly structures: single‐ and double‐layered double‐helix tubulin tubules. The phase transitions from MTs to the new assemblies are dependent on the size and concentration of polycations. Two characteristic scales that determine the number of observed phases are the size of polycation compared to the size of tubulin (≈4 nm) and to MT diameter (≈25 nm). This work suggests the feasibility of using polycations that have scissor‐ and glue‐like properties to achieve “programmable breakdown” of protein nanotubes, tearing MTs into double‐stranded tubulins and building up previously undiscovered nanostructures. Importantly, a new role of tubulins is defined as 2D shape‐controllable building blocks for supramolecular architectures. These findings provide insight into the design of protein‐based functional materials, for example, as metallization templates for nanoscale electronic devices, molecular screws, and drug delivery vehicles.