A working stock of all native standards was prepared at 5 mg/L in pure methanol and diluted as required to obtain the desired concentration of calibration standards.
A native Scottish standard emerged gradually during the 17th century, as poets ignorant of the Irish norm began to compose in their native dialects.
Flash is still a more capable technology when it comes to rendering video, but HTML5 is advancing faster and as a native Web standard it has many other advantages which may help it win over time.
They were included if they could speak English to native standard.
The native standards were supplied at concentrations of 2, 10, 40, 200 and 800 ng/ml (product codes PAH-A-CS1, PAH-A-CS2, PAH-A-CS3, PAH-A-CS4 and PAH-A-CS5, respectively); each solution contained the mass labelled analogues each at 100 ng/ml.
The native standards were obtained from LGC Promochem, Wesel, Germany (Pesticide-Mixture No. 41), and the respective internal 13C12-labeled standards were delivered by Cambridge Isotope Laboratories via LGC Promochem.
For regular monitoring of analytical method performance, unsmoked/blank CFPs were fortified with 40 ng of native standards, 100 ng of internal standards and extracted following the analytical procedure (Additional file 1: Table S8).
All native standards were procured from Sigma-Aldrich (St . Louis MO) except perfluorohexadecanoic acid (PFHxDA) from Matrix Scientific (Columbia, SC); meprobamate from Cerilliant (Round Rock, TX); and triclosan from Alfa Aesar (Ward Hill, MA).
For components analyzed the relevant native standards were used.
For 84 of these 103 compounds we confirmed identification by comparison of retention times with native standards.
