In this paper the results obtained using two validated gaschromatographic procedures on drinking water for the determination of trihalomethanes are compared. The volatile compounds, chloroform (CF), bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform (BF) were detected by purge and trap capillary column gas-chromatography with electrolytic conductivity detector ( ELCD) and th...

It is demonstrated how a commercially available MEMS thermopile infrared radiation sensor can be used as thermal conductivity gas detector (TCD). Since a TCD requires a heater while IR-thermopile sensors have no integrated heater, the thermopile itself is used as heater and temperature sensor at the same time. It is exposed to the measured gas environment in its housing. It is shown that, by us...

The quantitative analysis of a number of carbamate and urea herbicides in selected foods was examined. The compounds were extracted from the crops with ethanol which was subsequently partitioned between water and chloroform. The organic extract was evaporated to dryness and alkylated with sodium hydride-methyl iodide. The products were extracted with hexane and directly analyzed by gas chromato...

Surface Penetrating Radars (SPR) are extensively used in Military, Civil, Geophysical and Archaeological applications. In recent times there has been an increasing emphasis on the use of SPRs in the identification of the buried unexploded ordnance, such as anti tank mines, antipersonnel mines etc., which can be metallic or plastic in nature. Mine detection methods can be classified as destructi...

Two-dimensional black phosphorus is a new material that has gained widespread interest as an active material for optoelectronic applications. It features high carrier mobility that allows for efficient free-carrier absorption of terahertz radiation, even though the photon energy is far below the bandgap energy. Here we present an efficient and ultrafast terahertz detector, based on exfoliated m...

The carbon dioxide flux at the air/water interface in lakes was calculated after the determination of H2CO3* (free CO2) and atmospheric CO2 using flow injection analysis (FIA) coupled to a conductometric detector. The method is based on the diffusion of CO2 through a hydrophobic membrane into a flow of deionized water, generating a gradient of conductivity proportional to the concentration of C...

Various commercially available ultra-fast temperature programming approaches were integrated to silicon micromachined GC (micro-GC) for performance improvement assessment. The combined technique of micro-GC and ultra-fast temperature programming up to a rate of 6°C/second yielded an extended analysis range to undecane (nC(11)), improved signal detectability by at least a factor of three for the...

We report a chromatographic technique in which a vortex method of gas extraction and a thermal conductivity detector are used to measure carbon monoxide in blood. This method has the advantages of a small sample volume (100 l), a rapid analysis time (3 mm), ease of operation, and a high correlation with results of the standard gasometric method over the entire possible range (r = 0.999). The ac...

The HERA-B Outer Tracker consists of drift tubes folded from polycarbonate foil and is operated with Ar/CF4/CO2 as drift gas. The detector has to stand radiation levels which are similar to LHC conditions. The first prototypes exposed to radiation in HERA-B suffered severe radiation damage due to the development of self-sustaining currents (Malter effect). In a subsequent extended R&D program m...

In this article, we discuss an uncooled infrared IR detector based on an “arch-type” design realized with advanced microelectromechanical systems technology. Bimaterial microcantilevers undergo bending as their temperature changes due to the absorption of infrared photons. The bending is proportional to dissimilar thermal expansion of the two different materials composing the cantilever. We sel...