Recent and future re-entry vehicle designs use ablative material as the main component of the heat shield of their thermal protection systems. In order to properly predict the behavior of the vehicle, it is imperative to take into account the gases produced by the ablation process when modeling the reacting flow environment. In the case of charring ablators, where an inner resin is pyrolyzed at...

Peatlands represent a globally important carbon store; however, the human exploitation of this ecosystem is increasing both the frequency and severity of fires on drained peatlands. Yet, the interactions between the hydrological conditions (ecotopes), the fuel types being burned, the burn severity, and the charring temperatures (pyrolysis intensity) remain poorly understood. Here we present a p...

In this paper, the magnetic properties of carbon based material, graphene is studied, which is generated by laser ablation in cryogenic media. Transmission electron microscopy (TEM) and alternating gradient force magnetometer (AGFM) are applied to investigate the graphene morphology and magnetic properties, respectively. The graphene synthesized by the laser ablation method exhibits diamagnetic...

In 2008, a medieval wooden shipwreck was discovered at the port of Rhodes, Greece. The party burned, presenting challenge for conservators, as uncharred, semi-charred and charred waterlogged wood were often encountered on same piece timber. seeking most appropriate conservation method this unusual material, its chemical characterization considered necessary. This study examined chemistry three ...

BACKGROUND Lack of an irrigated-tip magnetic catheter has limited the role of remote-controlled magnetic navigation (Niobe II, Stereotaxis) for catheter ablation of atrial fibrillation (AF). METHODS AND RESULTS A novel 3.5-mm-tip irrigated magnetic catheter (group 1, Thermocool Navistar RMT, Biosense Webster) was used for 3D left atrial reconstruction (CARTO RMT) and remote-controlled magneti...

Experiments were conducted to characterize fire properties of wood exposed to the certain external heat flux and under variety of wood moisture content. Six kinds of Indonesian wood: keruing, sono, cemara, kamper, pinus, and mahoni were exposed to radiant heat from a conical heater, result in appearance of a stable flame on the wood surface caused by spontaneous ignition. A thermocouple K-type ...

Charring of organic carbon (OC) during thermal/optical analysis is monitored by the change in a laser signal either reflected from or transmitted through a filter punch. Elemental carbon (EC) in suspended particulate matter collected on quartz-fiber filters is defined as the carbon that evolves after the detected optical signal attains the value it had prior to commencement of heating, with the...

Arc ablation holds the promise of fast, low-cost metal removal at faster rates than laser, plasma and electron-beam methods and without the tooling and fixturing forces of conventional machining. Preliminary results show surface finishes in the tens of microns range at high material removal rates (MRRs) by adaptive control of arc voltage: up to 97 mm3/sec at 4 kW. These results far exceed the c...