AC Magnetic Susceptibility: Mathematical Modeling and Experimental Realization on Poly-Crystalline and Single-Crystalline High-T Superconductors YBaCuO and BiPbSrCaCuO.

The multifaceted inductive technique of AC magnetic susceptibility (ACMS) provides versatile and reliable means for the investigation of the respective properties of magnetic and superconducting materials. Here, we explore, both mathematically and experimentally, the ACMS set-up, based on four coaxial pick-up coils assembled in the second-derivative configuration, when employed in the investigation of differently shaped superconducting specimens of poly-crystalline YBaCuO and BiPbSrCaCuO and single-crystalline YBaCuO. Through the mathematical modeling of both the ACMS set-up and of linearly responding superconducting specimens, we obtain a closed-form relation for the DC voltage output signal.

Microstructure-driven annihilation effects and dispersive excited state dynamics in solid-state films of a model sensitizer for photon energy up-conversion applications.

Bimolecular processes involving exciton spin-state interactions gain attention for their deployment as wavelength-shifting tools. Particularly triplet-triplet annihilation induced photon energy up-conversion (TTA-UC) holds promise to enhance the performance of solar cell and photodetection technologies. Despite the progress noted, a correlation between the solid-state microstructure of photoactuating TTA-UC organic composites and their photophysical properties is missing.

Comparative Study of Polyethylene Films Embedded with Oxide Nanoparticles of Granulated and Free-Standing Nature.

Nanocomposite polymer films are a very diverse research field due to their many applications. The search for low-cost, versatile methods, producing regulated properties of the final products, has thus become extremely relevant. We have previously reported a bulk-scale process, dispersing granulated metal oxide nanoparticles, of both unary and multi-component nature, in a low-density polyethylene (LDPE) polymer matrix, establishing a reference in the produced films' optical properties, due to the high degree of homogeneity and preservation of the primary particle size allowed by this method.

Biogas upgrading to methane and removal of volatile organic compounds in a system of zero-valent iron and anaerobic granular sludge.

The current study presented a novel process of biogas upgrading to biomethane (higher than 97%) based on anaerobic sludge and zero-valent iron (ZVI) system. When ZVI was added into an aquatic system with anaerobic granular sludge (AnGrSl) under anaerobic abiotic conditions, H was generated. Then, the H and CO were converted by the hydrogenotrophic methanogens to CH.

Synthesis and Characterization of Hydrogenated Diamond-Like Carbon (HDLC) Nanocomposite Films with Metal (Ag, Cu) Nanoparticles.

In this work, the synthesis and characterization of hydrogenated diamond-like carbon (HDLC) nanocomposite thin films with embedded metallic Ag and Cu nanoparticles (NPs) are studied. These nanocomposite films were deposited using a hybrid technique with independent control over the carbon and metal sources. The metallic nanoparticles were directly deposited from the gas phase, avoiding surface diffusion of metal species on the deposition surface.

Metal (Ag/Ti)-Containing Hydrogenated Amorphous Carbon Nanocomposite Films with Enhanced Nanoscratch Resistance: Hybrid PECVD/PVD System and Microstructural Characteristics.

This study aimed to develop hydrogenated amorphous carbon thin films with embedded metallic nanoparticles (a-C:H:Me) of controlled size and concentration. Towards this end, a novel hybrid deposition system is presented that uses a combination of Plasma Enhanced Chemical Vapor Deposition (PECVD) and Physical Vapor Deposition (PVD) technologies. The a-C:H matrix was deposited through the acceleration of carbon ions generated through a radio-frequency (RF) plasma source by cracking methane, whereas metallic nanoparticles were generated and deposited using terminated gas condensation (TGC) technology.

Nanocomposite catalysts producing durable, super-black carbon nanotube systems: applications in solar thermal harvesting.

A novel two-step approach for preparing carbon nanotube (CNT) systems, exhibiting an extraordinary combination of functional properties, is presented. It is based upon nanocomposite films consisting of metal (Me = Ni, Fe, Mo, Sn) nanoparticles embedded into diamond-like carbon (DLC). The main concept behind this approach is that DLC inhibits the growth of Me, resulting in the formation of small nanospheres instead of layers or extended grains.