Quantum confinement was found to play a critical role in the formation of Au(111) islands grown on the surface of MoS 2 . These confinement effects are fully three dimensional, with a strong correlation to the relatively large Fermi wavelength associated with the Au(111) planes.The confinement effects result in preferred heights with a periodicity of nearly 2 nm and persist to much higher temperatures than are typically seen in electronic growth mode systems. These findings indicate the potential to explore electronic growth modes in a new class of systems based on metal -layered semiconductor interfaces.

The efficacy of an aged, fragmented preparation of immune serum globulin (human) as an agent for passive immunization was examined by comparing its performance in passive immunization with that of a fresh, unfragmented preparation. Guinea pigs passively immunized with the fresh preparation were protected against doses of tetanus toxin that were lethal to pigs which had received similar amounts of tetanus antitoxin as aged material.Monkeys passively immunized by intramuscular or intravenous injections of fresh immune serum globulin had levels of polio antibody in their serum which were consistently seven times higher than those produced by injection of the aged material. Urine collected from the monkeys treated with the aged material contained quantities of both polio and tetanus antibody as Fab fragment. After the intravenous injection of the aged material more than half of the injected antibody appeared in the urine within 24 hours.

Nanoscale device fabrication requires control over film growth at the atomic scale. Growth conditions must be tuned in consideration of interface parameters like chemical bonding, surface free energy, and lattice matching. In metals, electronic properties may also be utilized for control of physical parameters. Quantum size effects can induce metals to spontaneously form specific shapes and sizes according to their electronic structure. Unfortunately, such electronic growth is generally known only for a few systems and is typically only stable under cryogenic conditions. In this work, we explore a recently discovered class of electronic growth systems in which metal films are grown upon the relatively inert surfaces of van der Waals crystals. In this class of materials, the electronic growth is highly stable at room temperature and actually requires higher temperature annealing to achieve proper equilibrium. We work with the Au/MoS 2 system, which shows excellent stability and can readily form discrete and atomically flat nanostructures. Here, we show how the electronic growth modes facilitate the formation of atomically flat films with nanometer scale thickness. The surface roughness of these films was found to be less than a single atom over several square microns, creating nearly perfect surfaces for studies of self-assembled monolayers or other applications.

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Ultrasonic agitation is a proven method for breaking down layered materials such as MoS 2 into single or few layer nanoparticles. In this experiment, MoS 2 powder is sonicated in isopropanol for an extended period of time in an attempt to create particles of the smallest possible size. As expected, the process yielded a significant quantity of nanoscale MoS 2 in the form of finite layer sheets with lateral dimensions as small as a few tens of nanometers. Although no evidence was found to indicate a larger the longer sonication times resulted in a significant increase in yield of single layer MoS 2 , the increased sonication did result in the formation of several types of carbon allotropes in addition to the sheets of MoS 2 . These carbon structures appear to originate from the breakdown of the isopropanol and consist of finite layer graphite platelets as well as a large number of multi-walled fullerenes, also known as carbon onions. Both the finite layer graphite and MoS 2 nanoplatelets were both found to be heavily decorated with carbon onions. However, isolated clusters of carbon onions could also be found. Our results show that liquid exfoliation of MoS 2 is not only useful for forming finite layer MoS 2 , but also creating carbon onions at room temperature as well.