Lexikon

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Mind
atomic absorption spectrometry
abbreviated as AAS, the most common technique for detecting elements. It is a high through-put method: it takes not more than 5-6 min to measure the concentration of an element. Atoms of the element of interest in the sample are reduced to free, unexcited ground state atoms, which absorb light at characteristic wavelengths. The decrease in the light intensity is in direct connection with the concentration of the atoms absorbing the light at the given wavelength. Atomization can be induced by flame (flame atomic absorption spectroscopy) or with graphite furnace (graphite furnace atomic absorption spectroscopy). The method is widely applied for determination of elements in environmental samples (soil, ground water, sludge, sediment) and in wastes. Atomic absorption spectrometry is a fairly universal analytical method for determination of metallic elements when present in both trace and major concentrations. The EPA employs this technique for determining the metal concentration (dissolved, suspended and total) in samples from a variety of matrices. About 70 elements can be measured except B, C, N, O, S, halogens, noble gases and transuranic elements with short life time. A disadvantage of the AAS technique is the non linearity of the calibration curves when absorbance becomes higher than 0.5 to 1. Detection limits (LOD) for flame AAS vary enormously: from 1 - 5 ppb (e.g. Ca, Cd, Cr, Cu) to more than 1000 ppb (e.g. P).
atomic absorption spectroscopy being founded analysis
common technical specification

common technical specification is a technical specification drawn up in accordance with a procedure recognized by the Member States with a view to uniform application in all Member States and published in the Official Journal of the European Communities.

Source: Council Directive 93/38/EEC of 14 June 1993 coordinating the procurement procedures of entities operating in the water, energy, transport and telecommunications sectors.
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993L0038:EN:HTML

conservation status of a species

conservation status of a species means the sum of the influences acting on the species concerned that may affect the long-term distribution and abundance of its populations within the territory referred to in Article 2;

The conservation status will be taken as "favourable" when:

- population dynamics data on the species concerned indicate that it is maintaining itself on a long-term basis as a viable component of its natural habitats, and

- the natural range of the species is neither being reduced nor is likely to be reduced for the foreseeable future, and

- there is, and will probably continue to be, a sufficiently large habitat to maintain its populations on a long-term basis.

Source: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora.
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0043:EN:html

D-value: site specific remedial target value of the Hungarian soil regulation

it is a risk based target concentration for contaminated sites and contaminates soils. The Hungarian low requires the calculation of this target concentration in the remedial plan. The D-value is land-use specific.

flame atomic absorption spectrometry
a method for elemental analysis, abbreviated as FAAS. The sample is atomised in the flame, through which radiation of a chosen wavelength (using a hollow cathode lamp) is sent. The amount of absorbed radiation is a quantitative measure for the concentration of the element to be analysed. The gas mixtures used are hydrocarbons, e.g. methane, propane, propane-butane, air/acetylene and nitrous-oxide/acetylene. The latter resulting in higher atomisation efficiencies and thus better detection limits for elements like Si, Al, Sc, Ti, V and Zr. The air/acetylene flame can be used for easy atomisable elements (e.g. As and Se). The temperature of the flame is 2300 oC, high enough for atomization of the most frequently measured 30 elements. The liquid samples are introduced by nebulization, most frequently by pneumatic nebulization, PN, for the solid samples laser ablation and electrothermal vaporization. (Source: Posta József: Atomabszorpciós spektrometria. Debreceni Egyetem, 2008, Kempelen Farkas Digitális Tankönyvtár. www.tankonyvtar.hu/kemia/atomabszorpcios-080904-63). The method is useful for elemental analysis of environmental (soil, groundwater, sludge, deposit) and waste samples.
graphite furnace atomic absorption spectroscopy
a technique for elementary analysis using electrothermal atomization, abbreviated as GAAS. Samples in solution or in solid form are deposited on the surface of a graphite tube, which is then heated to high temperature to vaporize and thermally dissociate the sample. Graphite can be heated reproducibly; it will be sublimated at 3700 oC. The experimental error in measurement of solid samples can be decreased by measuring suspensions. The method is used for environmental samples (soil, ground water), solid and liquid wastes.
indicator species

indicator species maybe bacteria or other microorganisms, fungi, plant or animal species whose prescence, abundance, and health reveal the general condition of its habitat.

intervening-specifikus technological limit value onto air polluting substancesv
mass spectrometry
multispecies ecotoxicological tests
perspective traffic for noise-protection
Predicted Environmental Concentration (PEC)
protected species

a protected species is any plant or animal a government declares by law to warrant protection. Most protected species are considered either threatened or endangered. In these cases, a government establishes certain rules regarding the species, that if violated, can result in fines or criminal prosecution.

The impetus behind protected species laws is risk of species extinction. Ecologists have demonstrated that losing even the smallest of species can have a direct effect on the rest of the plant and animal population. For example, a grass eaten by a specific animal becomes extinct due to habitat destruction. The animal may die off as a result of not finding its food source available, causing further disruptions in the food chain.

Source: http://www.wisegeek.com/what-is-a-protected-species.htm

site-specific pollution limit value
sound spectrum band
sound spectrum octave band
species of Community interest

species of Community interest means species which, within the territory referred to in Article 2, are:

(i) endangered, except those species whose natural range is marginal in that territory and which are not endangered or vulnerable in the western palearctic region; or

(ii) vulnerable, i.e. believed likely to move into the endangered category in the near future if the causal factors continue operating; or

(iii) rare, i.e. with small populations that are not at present endangered or vulnerable, but are at risk. The species are located within restricted geographical areas or are thinly scattered over a more extensive range; or

(iv) endemic and requiring particular attention by reason of the specific nature of their habitat and/or the potential impact of their exploitation on their habitat and/or the potential impact of their exploitation on their conservation status.

Such species are listed or may be listed in Annex II and/or Annex IV or V;

Source: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora.
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0043:EN:html

specific surface
X-ray fluorescence spectrometric analysis
XRF (X-ray fluorescence spectrometry) is a non-destructive analytical technique used to identify and determine the concentrations of elements present in solid, powdered and liquid samples. The atoms of the analyte are illuminated by X-ray and the excited atoms discharge fluorescent radiation. The energy (wavelength) of the emitted radiation is characteristic to the element, the intensity is proportional to the abundance (concentration) of the element. The analysis is based on a calibration with samples containing known elements. XRF is capable of measuring elements from beryllium (Be) to uranium (U) and beyond at trace levels often below one part per million and up to 100%. The concentration measurement is influenced by the matrix (matrix effect). The XRF spectrometer measures the individual component wavelengths of the fluorescent emission produced by a sample when irradiated with X-rays. Typical environmental applications: at wood treating facilities determination of chromium, arsenic and pentachlorophenol; in numerous other sites toxic metals such as lead, mercury, arsenic and cadmium. XRF is commonly used as a screening tool to identify contaminated areas that must be remedied. Smaller instruments, even hand held devices might be used on site, while higher end instruments are used in the lab. (Source: www.panalytical.com)