Human exposures to volatile organic compounds (VOCs) are associated with a wide range of health problems. Due to these adverse effects of VOCs on the human health, determination of trace levels of VOCs is very important for accurate assessment of indoor and outdoor exposure. Solid phase microextraction (SPME), needle trap device (NTD) and hollow fiber- liquid phase microextraction (HF-LPME) are...

A simple and cost effective solid-phase microextraction device has been developed. Fused-silica capillaries were etched with ammonium hydrogen difluoride prior to coating with an ionic liquid. For comparison, both a bare fused-silica capillary and one pretreated with a Nafion membrane were coated with the ionic liquid. All three coated capillaries were employed for the head space microextractio...

This article reviews the recent developments in Bio-Analytical sample preparation techniques and gives an update on basic principles, Applications and comparative discussion on the advantages and limitations of each technique. Conventional Solid-Phase Extraction (SPE), Molecularly Imprinted Polymer SPE techniques are have been considered as methods of past. Developments in SPE techniques such a...

Electromembrane extraction (EME) is an analytical microextraction technique, where charged analytes (such as drug substances) are extracted from an aqueous sample (such as a biological fluid), through a supported liquid membrane (SLM) comprising a water immiscible organic solvent, and into an aqueous acceptor solution. The driving force for the extraction is an electrical potential (dc) applied...

Background and Objectives: Heterocyclic aromatic amines (HAAs) are carcinogenic and mutagenic substances, which are formed during the heating process of proteinaceous foods such as meat and meat products. The extraction of these compounds from the complex matrix of meat products was carried out by microwave assisted pre-extraction and a precise, rapid and high sensitive microextraction method. ...

A novel sorbent in solid phase microextraction (SPME) method based on poly(3-alkylthiophenes) was used in the isolation of linezolid from human plasma samples following liquid chromatography determination. The effect of extraction time on the sorption capacity of the SPME process was studied and pointed at 10 min both for adsorption and desorption. Poly(3-methylthiophene) and poly(3-nonylthioph...

Measurements of rain were obtained with a vertically pointing micro radar (MRR) with 1 min time resolution and 50(100) m height resolution at the German Baltic coast on the Zingst peninsula (54.43°N, 12.67°E). The comparison with a conventional rain gauge (30 min integration time) for a fi ve months summer period show a correlation coeffi cient of r = 0.87 for the rainrate and agreement within ...

This paper presents a study of the national electric power, showing the Brazil consumes electricity in a year and how much you could save if thermoelectric modules were used in some industries and new cars and planes to capture and transformation of residual thermal energy into electrical energy. The conclusion appears really attractive economically, given the fact that many processes generate ...

A novel direct-laser writing fabrication process for micro-axicons is demonstrated. A fiber-axicon-generated Bessel beam was utilized to write on UV-curable optical epoxy to form new axicons and axicon arrays, and geometrical parameters of the replicated epoxy axicons were analyzed in terms of both apex angle and proximity of the writing axicons. The shape of the fabricated axicons was demonstr...

In order to combat a variety of pests, pesticides are widely used in fruits. Several extraction procedures (liquid extraction, single drop microextraction, microwave-assisted extraction, pressurized liquid extraction, supercritical fluid extraction, solid-phase extraction, solid-phase microextraction, matrix solid-phase dispersion, and stir bar sorptive extraction) have been reported to determi...