the major sources of pahs are anthropogenic. these may be generated by pyrolytic and petrogenic processes. low molecular weight pahs come into the aquatic system through the accidentally leakage of oil spills. incomplete combustion at high temperature will release high molecular weight pahs by products of pyrolytic processes. the methods for assigning sources of pahs include paired isomeric rat...

We report on spectroscopic study of pyrolytic hBN (pBN) by means of time-and energy-resolved photoluminescence methods. A high purity of pBN samples (though low crystallinity) allows complementary information about excited states involved into the luminescence process. We affirm our recent conclusions about the impurity-related nature of most of the fluorescence bands in microcrystalline hBN. I...

BACKGROUND Osteochondral defects continue to be a clinical treatment challenge, and when left untreated, may cause pain and functional impairment. Pyrolytic carbon is a unique isotropic biomaterial used in heart valve and small joint replacements due to its excellent wear properties and biocompatibility with bone and articular cartilage. Therefore, a proposed solution is to utilize a focal pyro...

The articulating surfaces of four different sizes of unused pyrolytic carbon proximal interphalangeal prostheses (PIP) were evaluated though measuring several topographical parameters using a white light interferometer: average roughness (Sa); root mean-square roughness (Sq); skewness (Ssk); and kurtosis (Sku). The radii of the articulating surfaces were measured using a coordinate measuring ma...

Recent developments on the relationship between the complex microstructure of pyrolytic carbon coatings and the pyrolysis conditions are reviewed. Pyrolytic carbon coatings deposited on carbon fibers and non-carbon substrates are studied comparatively by light microscopy, scanning electron microscopy and transmission electron microscopy combined with selected-area electron diffraction. Opticall...

We report a comparative study of optical properties of 5-20 nm thick pyrolytic carbon (PyC) films, graphite, and graphene. The complex dielectric permittivity of PyC is obtained by measuring polarization-sensitive reflectance and transmittance spectra of the PyC films deposited on silica substrate. The Lorentz-Drude model describes well the general features of the optical properties of PyC from...

A challenge in recent years has been the rational use of forest and agriculture residues for the production of bio-fuel, biochemical, and other bioproducts. In this study, potentially useful compounds from pyrolytic lignins were identified by HPLC-MS/MS and untargeted metabolomics. The metabolites identified were 2-(4-allyl-2-methoxyphenoxy)-1-(4-hydroxy-3-methoxyphenyl)-1-propanol, benzyl benz...

Pyrolytic carbon has many properties that make it suitable for use in the replacement of small joints [1]. The material has a modulus of elasticity similar to that of bone, good wear and fatigue properties, and excellent biocompatibility. Its biggest disadvantage is inadequate biological fixation. The as-deposited surface of pyrolytic carbon has a pore size of 5-10 μm and a depth of 20 μm. This...

Minute concentrations of suspended particles can dramatically alter the behavior of a drying droplet. After a period of isotropic shrinkage, similar to droplets of a pure liquid, these droplets suddenly buckle like an elastic shell. While linear elasticity is able to describe the morphology of the buckled droplets, it fails to predict the onset of buckling. Instead, we find that buckling is coi...