The chemical basis for improved removal rates of toxic heavy metals such as Zn and Cu from wastewater secondary sludge has been demonstrated in this study. Instead of using excess corrosive chemicals as the source of free nitrous acid (FNA) for improved solubility of heavy metals in the sludge (in order to enhance electrokinetics), an optimized use of aqua regia has been proposed as an alternat...

The chemical and physical properties of platinum (Pt) make it a useful material for microelectromechanical systems and microfluidic applications such as lab-on-a-chip devices. Platinum thin-films are frequently employed in applications where electrodes with high chemical stability, low electrical resistance or a high melting point are needed. Due to its chemical inertness it is however also one...

The transport characteristics of graphene devices with low n- or p-type carrier density (∼10(10) -10(11) cm(-2) ), fabricated using a new process that results in minimal organic surface residues, are reported. The p-type molecular doping responsible for the low carrier densities is initiated by aqua regia. The resulting devices exhibit highly developed ν = 2 quantized Hall resistance plateaus a...

Various studies have focused on the performance and removal mechanism of aqueous Hg using biochars, but specific process has not been fully elucidated. Aqua regia digestion is considered a common extraction method from solid samples, uncertainties exist regarding biochars. Aqueous kinetic experiments followed by aqua procedures solid-phase analyses were conducted to investigate diffusion transf...

Sediments as a tool for monitoring contamination by heavy metals in the environment has long been considered. It is therefore a necessity to produce reliable data for such purposes. Microwave-assisted acid dissolution has proved to be a suitable method for digesting complex matrices, such as sediments. However, due to the infancy of the technique, the procedures are numerous and varied in both ...

Quantification of metal loading in supported catalysts is imperative; however, the analytical methods are usually time-consuming, expensive, and require sophisticated equipment and sample extraction with hazardous and corrosive strong acids. Herein, we report a new method for quantification of metal in supported catalysts using slurry sampling flame atomic absorption spectrometry. The slurry sa...

Legislation limits for risk elements (As, Be, Cd, Co, Cr, Cu, Ni, Pb, V, Zn) in agricultural soil the Czech Republic are given content of extracted by aqua regia. This extraction is time consuming and environmentally unfriendly. The regular survey based on Mehlich 3 universal extractant covers simultaneous determination macronutrients, sulphur, micronutrients inductively coupled plasma optical ...