24 research outputs found
Graphene Materials - Advanced Applications
Graphene is, basically, a single atomic layer of graphite, an abundant mineral that is an allotrope of carbon that is made up of very tightly bonded carbon atoms organized into a hexagonal lattice. What makes graphene so special is its sp2 hybridization and very thin atomic thickness (of 0.345 Nm). These properties are what enable graphene to break so many records in terms of strength, electricity, and heat conduction (as well as many others). This book gathers valuable information about many advanced applications of graphene (electrical, optical, environmental, cells, capacitors, etc)
Graphene Materials - Structure, Properties and Modifications
Graphene is, basically, a single atomic layer of graphite, an abundant mineral that is an allotrope of carbon that is made up of very tightly bonded carbon atoms organized into a hexagonal lattice. What makes graphene so special is its sp2 hybridization and very thin atomic thickness (of 0.345 Nm). These properties are what enable graphene to break so many records in terms of strength, electricity, and heat conduction (as well as many others). This book gathers valuable information about the surface chemistry of graphene, some of its properties (electrical, mechanical, etc.), and many of its modifications that can be taken into account
Scanning of adsorption hysteresis in situ with small angle x-ray scattering
Everett's theorem-6 of the domain theory was examined by conducting adsorption in situ with small angle x-ray scattering (SAXS) supplemented by the contrast matching technique. The study focuses on the spectrum differences of a point to which the system arrives from different scanning paths. It is noted that according to this theorem at a common point the system has similar macroscopic properties. Furthermore it was examined the memory string of the system. We concluded that opposite to theorem-6: a) at a common point the system can reach in a finite (not an infinite) number of ways, b) a correction for the thickness of the adsorbed film prior to capillary condensation is necessary, and c) the scattering curves although at high-Q values coincide, at low-Q values are different indicating different microscopic states. That is, at a common point the system holds different metastable states sustained by hysteresis effects. These metastable states are the ones which highlight the way of a system back to a return point memory (RPM). Entering the hysteresis loop from different RPMs different histories are implanted to the paths toward the common point. Although in general the memory points refer to relaxation phenomena, they also constitute a characteristic feature of capillary condensation. Analogies of the no-passing rule and the adiabaticity assumption in the frame of adsorption hysteresis are discussed
The Effect of Nanobubbles on Transdermal Applications
In the present work, a new method for dermal delivery using nanobubbles (NBs) is investigated. Oxygen NBs are generated in deionized water and used to produce cosmetic formulations with hyaluronic acid as an active ingredient. Nanobubbles result in the improvement of the effect and penetration of the active ingredient through Strat-M, a synthetic membrane that resembles human skin. Experiments conducted with the Franz Cell device confirm the greater penetration of the active ingredient into Strat-M due to NBs, compared to cosmetic formulations that do not contain NBs. The effect of NBs was further examined by measuring UV-Vis and FTIR spectra. A possible mechanism was outlined, too. It was also found that NBs do not change the pH or the FTIR spectrum of the cosmetic serum indicating non-toxicity
Scanning adsorption hysteresis <i>in situ</i> with SAXS.
<p>Scanning adsorption hysteresis <i>in situ</i> with SAXS.</p
Effect of the adsorbed film on scanning the hysteresis loop of CH<sub>2</sub>Br<sub>2</sub>/Vycor adsorption isotherm according to theorem-6 of the domain theory.
<p>Points Λ and Ξ are approached from different routes; ΑΛΞΟ is a primary descending curve originated from the ascending boundary p(x) and CΞDΛC is a loop originated from the descending boundary q(x), α and O are respectively the upper and lower closure points of the adsorption isotherm. The complexion diagrams for common points are shown too; hatched areas indicate the correction needed to be taken into account for the adsorbed film in order theorem-6 to be valid. Note that the thickness of the film increases with pressure.</p
Investigation of Water Sorption on Porcine Stratum Corneum by Very Small Angle Neutron Scattering
Scanning of the hysteresis loop <i>in situ</i> with SAXS.
<p>Point Z is approached from three different routes; ΑBPCHZ and EZ originated from the desorption branch of the adsorption isotherm and DZ originated from the adsorption branch of the adsorption isotherm. The complexion diagrams for Z are shown and the hatched areas indicate the correction for the adsorbed film. The spectra which correspond to point Z from the different routes are shown too. The colors and letters are consistent with <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0164636#pone.0164636.g003" target="_blank">Fig 3</a> for easy inspection.</p