Lexikon

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vacuum exhaust

see vacuum exhaust of soil gas or soil vapour.

vadous soil zone
vadouse zone
vapour pressure
saturation pressure above a solid or liquid substance. A physico-chemical parameter required by REACH. This data is not used as a Classification and Labelling (C&L) (classification and labelling of chemicals) criterion or to define persistent, bioaccumulative and toxic (PBT) properties, but is a key parameter in determining the environmental fate and behaviour, for environmental and human health risk assessments. (http://www.prc.cnrs-gif.fr/reach/en/physicochemical_data.html) The study does not need to be conducted if the melting point is above 300C. If the melting point is between 200C and 300C, a limit value based on measurement or a recognised calculation method is sufficient.
Venturi scrubber

A Venturi scrubber is designed to effectively use the energy from the inlet gas stream to atomize the liquid being used to scrub the gas stream. This type of technology is a part of the group of air pollution controls collectively referred to as wet scrubbers. Venturi scrubbers are used to remove very fine dust and mist, and can also remove gases. They rely on high velocity airflow in the scrubber to atomise water and remove particles down into the submicron range.

Venturi scrubbers can have the highest particle collection efficiencies (especially for very small particles) of any wet scrubbing system.

They are the most widely used scrubbers because their open construction enables them to remove most particles without plugging or scaling. Venturis can also be used to absorb pollutant gases; however, they are not as efficient for this as are packed or plate towers.

Venturi scrubbers have been designed to collect particles at very high collection efficiencies, sometimes exceeding 99%. The ability of venturis to handle large inlet volumes at high temperatures makes them very attractive to many industries; consequently, they are used to reduce particulate emissions in a number of industrial applications.

Venturi- washing
verbal characterisation of risk of chemicals

67/548/EEC regulation uses the following riks-phrases for characterisation of the risk of dangerous chemical substances.

Risk Phrases

R1: Explosive when dry

R2: Risk of explosion by shock, friction, fire or other sources of ignition

R3: Extreme risk of explosion by shock, friction, fire or other sources of ignition

R4: Forms very sensitive explosive metallic compounds

R5: Heating may cause an explosion

R6: Explosive with or without contact with air

R7: May cause fire

R8: Contact with combustible material may cause fire

R9: Explosive when mixed with combustible material

R10: Flammable

R11: Highly flammable

R12: Extremely flammable

R14: Reacts violently with water

R15: Contact with water liberates extremely flammable gases

R16: Explosive when mixed with oxidising substances

R17: Spontaneously flammable in air

R18: In use, may form flammable/explosive vapour-air mixture

R19: May form explosive peroxides

R20: Harmful by inhalation

R21: Harmful in contact with skin

R22: Harmful if swallowed

R23: Toxic by inhalation

R24: Toxic in contact with skin

R25: Toxic if swallowed

R26: Very toxic by inhalation

R27: Very toxic in contact with skin

R28: Very toxic if swallowed

R29: Contact with water liberates toxic gas.

R30: Can become highly flammable in use

R31: Contact with acids liberates toxic gas

R32: Contact with acids liberates very toxic gas

R33: Danger of cumulative effects

R34: Causes burns

R35: Causes severe burns

R36: Irritating to eyes

R37: Irritating to respiratory system

R38: Irritating to skin

R39: Danger of very serious irreversible effects

R40: Limited evidence of a carcinogenic effect

R41: Risk of serious damage to eyes

R42: May cause sensitisation by inhalation

R43: May cause sensitisation by skin contact

R44: Risk of explosion if heated under confinement

R45: May cause cancer

R46: May cause heritable genetic damage

R48: Danger of serious damage to health by prolonged exposure

R49: May cause cancer by inhalation

R50: Very toxic to aquatic organisms

R51: Toxic to aquatic organisms

R52: Harmful to aquatic organisms

R53: May cause long-term adverse effects in the aquatic environment

R54: Toxic to flora

R55: Toxic to fauna

R56: Toxic to soil organisms

R57: Toxic to bees

R58: May cause long-term adverse effects in the environment

R59: Dangerous for the ozone layer

R60: May impair fertility

R61: May cause harm to the unborn child

R62: Possible risk of impaired fertility

R63: Possible risk of harm to the unborn child

R64: May cause harm to breast-fed babies

R65: Harmful: may cause lung damage if swallowed

R66: Repeated exposure may cause skin dryness or cracking

R67: Vapours may cause drowsiness and dizziness

R68: Possible risk of irreversible effects

Combinations

R14/15: Reacts violently with water, liberating extremely flammable gases

R15/29: Contact with water liberates toxic, extremely flammable gases

R20/21: Harmful by inhalation and in contact with skin

R20/22: Harmful by inhalation and if swallowed

R20/21/22: Harmful by inhalation, in contact with skin and if swallowed

R21/22: Harmful in contact with skin and if swallowed

R23/24: Toxic by inhalation and in contact with skin

R23/25: Toxic by inhalation and if swallowed

R23/24/25: Toxic by inhalation, in contact with skin and if swallowed

R24/25: Toxic in contact with skin and if swallowed

R26/27: Very toxic by inhalation and in contact with skin

R26/28: Very toxic by inhalation and if swallowed

R26/27/28: Very toxic by inhalation, in contact with skin and if swallowed

R27/28: Very toxic in contact with skin and if swallowed

R36/37: Irritating to eyes and respiratory system

R36/38: Irritating to eyes and skin

R36/37/38: Irritating to eyes, respiratory system and skin

R37/38: Irritating to respiratory system and skin

R39/23: Toxic: danger of very serious irreversible effects through inhalation

R39/24: Toxic: danger of very serious irreversible effects in contact with skin

R39/25: Toxic: danger of very serious irreversible effects if swallowed

R39/23/24: Toxic: danger of very serious irreversible effects through inhalation and in contact with skin

R39/23/25: Toxic: danger of very serious irreversible effects through inhalation and if swallowed

R39/24/25: Toxic: danger of very serious irreversible effects in contact with skin and if swallowed

R39/23/24/25: Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed

R39/26: Very Toxic: danger of very serious irreversible effects through inhalation

R39/27: Very Toxic: danger of very serious irreversible effects in contact with skin

R39/28: Very Toxic: danger of very serious irreversible effects if swallowed

R39/26/27: Very Toxic: danger of very serious irreversible effects through inhalation and in contact with skin

R39/26/28: Very Toxic: danger of very serious irreversible effects through inhalation and if swallowed

R39/27/28: Very Toxic: danger of very serious irreversible effects in contact with skin and if swallowed

R39/26/27/28: Very Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed

R42/43: May cause sensitization by inhalation and skin contact

R48/20: Harmful: danger of serious damage to health by prolonged exposure through inhalation

R48/21: Harmful: danger of serious damage to health by prolonged exposure in contact with skin

R48/22: Harmful: danger of serious damage to health by prolonged exposure if swallowed

R48/20/21: Harmful: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin

R48/20/22: Harmful: danger of serious damage to health by prolonged exposure through inhalation and if swallowed

R48/21/22: Harmful: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed

R48/20/21/22: Harmful: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed

R48/23: Toxic: danger of serious damage to health by prolonged exposure through inhalation

R48/24: Toxic: danger of serious damage to health by prolonged exposure in contact with skin

R48/25: Toxic: danger of serious damage to health by prolonged exposure if swallowed

R48/23/24: Toxic: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin

R48/23/25: Toxic: danger of serious damage to health by prolonged exposure through inhalation and if swallowed

R48/24/25: Toxic: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed

R48/23/24/25: Toxic: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed

R50/53: Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment

R51/53: Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment

R52/53: Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment

R68/20: Harmful: possible risk of irreversible effects through inhalation

R68/21: Harmful: possible risk of irreversible effects in contact with skin

R68/22: Harmful: possible risk of irreversible effects if swallowed

R68/20/21: Harmful: possible risk of irreversible effects through inhalation and in contact with skin

R68/20/22: Harmful: possible risk of irreversible effects through inhalation and if swallowed

R68/21/22: Harmful: possible risk of irreversible effects in contact with skin and if swallowed

R68/20/21/22: Harmful: possible risk of irreversible effects through inhalation, in contact with skin and if swallowed

R-Phrases no longer in use

R13: Extremely flammable liquefied gas.

R47: May cause birth defects.

verification
verified background concentration
vermikulit
very bioaccumulative substance

accordibng to REACH, a substance fulfils the very bioaccumulative criterion when:
– the bioconcentration factor is greater than 5 000.

The assessment of bioaccumulation shall be based on measured data on bioconcentration in
aquatic species. Data from freshwater as well as marine water species can be used.

See also bioaccumulative substance, vPvB substances

very persistent

according to REACH regulation a substance fulfils the very persistent criterion when:
– the half-life in marine, fresh- or estuarine water is higher than 60 days, or
– the half-life in marine, fresh- or estuarine water sediment is higher than 180 days, or
– the half-life in soil is higher than 180.

See also: persistent substance and very Persistent and very Bioccumulative Substances

very Persistent and very Bioccumulative Substances, vPvB

substances of very high concern, which are very persistent (very difficult to break down) and very bio-accumulative in living organisms. Annex XIII defines criteria for the identification of vPvBs and Annex I lays down general provisions for their assessment. vPvBs may be included in Annex XIV and by that be made subject to authorisation. (Source: REACH Glossary)

VGA, IT

Video Graphics Array (640 x 480)

vibration

a periodic motion of small amplitude and high frequency, characteristic of elastic bodies.

Vibrio fisheri
viscosity
intrinsic friction of a liquid (Erdey-Grúz T., Schay G.: Theoretical Physical chemistry, Tankönyvkiadó Budapest, 1964, in Hungarian), measure of the resistance of a fluid to being deformed by either shear stress or extensional stress (commonly perceived as resistance to pouring). A physico-chemical parameter required by REACH for materials manufactured or imported in >100 tons/year. This data is used in human health risk assessment (liquid substances and preparations may present an aspiration hazard in humans because of their low viscosity). (http://www.prc.cnrs-gif.fr/reach/en/physicochemical_data.html)
vitrification

vitrification is a technology which uses an electric current to melt contaminated soil at elevated temperatures (1,600 to 2,000°C or 2,900 to 3,650°F). Upon cooling, the vitrification product is a chemically stable, leachresistant, glass and crystalline material similar to obsidian or basalt rock. The high temperature component of the process destroys or removes organic materials. Radionuclides and heavy metals are retained within the vitrified product. Vitrification may be conducted in situ or ex situ.

VOC

abbreviation for Volatile Organic Compounds. There are several VOCs among hydrocarbons, such as BTEX.

volatile organic compounds

organic compounds that evaporate readily into the air. In the Hungarian air-regulation VOCs are defined as organic compounds, with higher vapour pressure than 0.01 kPa on 293.15 oK.

VOCs include substances such as benzene, toluene, methylene chloride, and methyl chloroform.

volcanic extrusive rocks

extrusive igneous rocks are formed at the Earth crust's surface as a result of the partial melting of rocks within the mantle and crust. The melt, with or without suspended crystals and gas bubbles, is called magma. When it REACHes the surface, magma extruded onto the surface either beneath water or air, is called lava. The lava cools and solidifies almost instantly when it is exposed to the relatively cool temperature of the atmosphere. Quick cooling means that mineral crystals don't have much time to grow, so these rocks have a very fine-grained or even glassy texture. Hot gas bubbles are often trapped in the quenched lava, forming a bubbly, vesicular texture. In terms of the composition the volcanic rocks are classified in three large groups: basalts (greyish black coloured), andesites (greyish, redbrown coloured), rhyolite (white coloured). In Hungary basalt rocks are to be found in the Balaton and Salgótarján area, while andesite rocks extend from the North Danube area to the Mátra. The Zemplén mountains are mostly made up of rhyolites and partly by andesites. See also volcanic rock, magmatic rock

volcanic pyroclastic rocks
volcanic rock

see also igneous rock

volcanic tuff
Voltile Organic Compounds
volatile organic compounds with high vapor pressure under normal conditions. Abbreviated as VOC. They can be of natural or synthetic origin. In the environmental chemistry the hydrocarbons of low boiling point, such as BTEX, and DRO range organics belong to VOCs.
VPH

Volatile petroleum hydrocarbons, that is the GRO (Gasoline Range Organics) consists of hydrocarbons containing between 6 and 10 carbon atoms and includes aromatic compounds, alkanes, cycloalkanes and branched alkanes. Approximately 40% of the hydrocarbons in fresh petrol are monoaromatic compounds such as benzene, toluene and ethylbenzene (BTEX). GRO is usually measured by headspace analysis or by purge and trap method. The sum of GRO and DRO gives TPH.



VTPH
Volatile Total petroleum hydrocarbons, see VPH, GRO