In an estuarine system, the flood tidal wave may become a tidal bore during the early flood tide in a narrow funnelled channel under large tidal ranges. Herein new experiments were conducted in a large flume to investigate breaking tidal bores and the bore roller propagation. The results demonstrated several key features of tidal bores propagating in rectangular channels. The propagation of the...

Six compounds were analyzed through isocratic elution to demonstrate the effect of several instrument, method, and sample variables on column performance. A very efficient Agilent InfinityLab Poroshell 120 EC-C18, 2.1 × 50 mm, 1.9 μm column capable of generating nearly 14,000 plates was used in this work. The impact on column performance of system capillaries, detector flow cells, data collecti...

Polar metabolites of the arginine biosynthetic pathway are poorly retained in reversed phase C18 chromatography. Hydrophilic interaction chromatography (HILIC) is an option for separating polar metabolites such as amino acids. However, compared to RP chromatography, peaks in HILIC separations are often broader and column re-equilibration requires a longer time. To enable metabolic profiling of ...

A simple and rapid analytical method was established for detection of anabolic agents, zeranol and alpha-trenbolone and beta-trenbolone residues in cattle muscle and liver. This method consisted of aqueous acetonitrile extraction and successive solid-phase extraction with a tandem connected octadecyl (C18)-aminopropyl (NH2) cartridge, followed by on-line clean-up using multidimensional HPLC wit...

Two fused-silica capillaries of considerably different inner diameter (75 and 10 microm) were used for the separation of a set of five standard proteins. The separations were run in acid pH (50 mM phosphate buffer, pH 2.5). Generally better separations (with minor tailing only) were obtained using a standard capillary [27 cm (20 cm effective length)x 75 microm I.D.] in comparison with a narrow ...

We report here an application of the previous method for the analysis of phosphatidylcholine (PC) and lysophosphatidylcholine (lysoPC) oxidation products in human plasma using quadrupole time of flight (Q-TOF) mass spectrometry with electrospray ionization. We separated these products using an HPLC C8 column with a gradient of methanol and 10 mM aqueous ammonium acetate. Monohydroperoxides, epo...

Isolated five known iridoids glycosides (Scrophuloside A, Harpagoside B, 5-hydroxyloganin, 8-O-acetylharpagide and 6-O-methyl,1-glucopyranosyl catalpol ),one phenyl ethanoid glycoside (Verbascoside) and a phenyl ethanol amine (2-(4-Chlorobenzyl amino) ethanol ) compound from the methanolic extract of aerial parts of Scrophularia oxysepala using by high performance liquid chromatography based on...

In serum, the primary indicator of vitamin D nutritional status is 25-hydroxyvitamin D [25(OH)D], whereas 1,25dihydroxyvitamin D [l,25(OH)2D1 reflects mineral and skeletal homeostasis. Essential for a reliable assay of 1,25(OH)2D in serum is its separation from 25(OH)D, because the latter circulates in a 1000-fold greater concentration and significantly cross-reacts with the receptors used in r...

Introduction: Xenobiotic contamination is a global concern. Nitroaromatic compounds enter the environment through ammunition, ordnance disposal, burning the outdoors, and leakage of ammunition. Thirty percent of explosives enter the environment without any change, which can cause pollution of soil, water, and health concerns. So, effective remediation of the contaminated area is necessary. Mat...

Isolated five known iridoids glycosides (Scrophuloside A, Harpagoside B, 5-hydroxyloganin, 8-O-acetylharpagide and 6-O-methyl,1-glucopyranosyl catalpol ),one phenyl ethanoid glycoside (Verbascoside) and a phenyl ethanol amine (2-(4-Chlorobenzyl amino) ethanol ) compound from the methanolic extract of aerial parts of Scrophularia oxysepala using by high performance liquid chromatography based on...