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Pollutants thermal properties

The Atmospheric Boundary Layer. The atmospheric boundary layer can be loosely defined as that portion of the lower atmosphere which manifests the effects of surface features in influencing wind flow. It often extends up to heights of the order of 1 km or to the height of the mixing layer, above which the thermal properties of the atmosphere may effectively insulate it from ground effects. The atmospheric boundary layer is the carrier for pollutants that affect corrosion. There are several properties of the atmospheric boundary layer of concern here ... [Pg.413]

Biirkiit, Y., Suner, F., and Nakhla, F.M. 1994. Thermal properties of coal. In Coal Resources, Properties, Utilization, Pollution, O. Kural (Ed.). Istanbul Technical University, Istanbul, Turkey, Chapter 6. [Pg.419]

The LST and total petroleum hydrocarbon (TPH) are positively correlated. The methodology followed is based on the fact that most of the satellites carry a thermal infra-red band which can be used for LST estimation. The spatio-temporal variation in the thermodynamic properties of surface material has been mapped in order to identify hydrocarbon polluted surfaces using Landsat TM data. Emissivity is a strong indicator of compositional variation in silicate minerals which make up the bulk of the earth s surface material. Emissivity affects the apparent temperature due to changes in the thermal properties of materials (conductivity, density, capacity, and inertia). There are several algorithms proposed to estimate LST from remotely sensed data. The most common of these are mono-window and split window methods [22-25], the latter was used initially to estimate sea surface temperature. [Pg.80]

The achievement of faithful studies on the material strength under indoor or outdoor climatic degradation depends strongly by the surface thermal properties. In the relationship that depicts the modeling of thermal conduction of outer layers, the contribution factors of fight intensity and spectrum, wind, humidity, rain frequency, pollutants, heat convection must be foreseen [25]. The rate of gas difhision into material is dependent on the pressure according with the Eq. (2) [26]. [Pg.197]

The development of catalysts for the oxidation of organic compounds by air under ambient conditions is of both academic and practical importance (1). Formaldehyde is an important intermediate in synthetic chemistry as well as one of the major pollutants in the human environment (2). While high temperature (> 120 °C) catalytic oxidations are well known (3), low temperature aerobic oxidations under mild conditions have yet to be reported. Polyoxometalates (POMs) are attractive oxidation catalysts because these extensively modifiable metal oxide-like structures have high thermal and hydrolytic stability, tunable acid and redox properties, solubility in various media, etc. (4). Moreover, they can be deposited on fabrics and porous materials to render these materials catalytically decontaminating (5). Here we report the aerobic oxidation of formaldehyde in water under mild conditions (20-40 °C, 1 atm of air or 02) in the presence of Ce-substituted POMs (Ce-POMs). [Pg.429]

The main objective of the work to be described here is to design and synthesize new organic dielectric materials, and to develop new techniques to deposit these materials as thin, thermally stable films with very low dielectric constants, for use as ILDs. New dielectric materials must not only possess proper electrical, thermal, and mechanical properties but should also minimize or eliminate the use of solvents in this era of concern for environmental pollution. [Pg.277]

In 2000, NEC developed an epoxy resin with what it describes as a fire-retardant structure that avoids the need for either TBBA or phosphorus-based flame retardants in circuit boards. The new resin contains a metal hydroxide retardant. The company claims the new board is almost totally free of pollutants, and is easy to process and thermally recycle. By also integrating flame retardant properties within the board, use of the metal hydroxide is minimised, while offering good electrical properties, higher heat resistance and improved processing characteristics. ... [Pg.20]

Chemical, Physical, and Mechanical Tests. Manufactured friction materials are characterized by various chemical, physical, and mechanical tests in addition to friction and wear testing. The chemical tests include thermogravimetric analysis (tga), differential thermal analysis (dta), pyrolysis gas chromatography (pgc), acetone extraction, liquid chromatography (lc), infrared analysis (ir), and x-ray or scanning electron microscope (sem) analysis. Physical and mechanical tests determine properties such as thermal conductivity, specific heat, tensile or flexural strength, and hardness. Much attention has been placed on noise /vibration characterization. The use of modal analysis and damping measurements has increased (see Noise POLLUTION AND ABATEMENT). [Pg.275]

New applications of zeolite adsorption developed recently for separation and purification processes are reviewed. Major commercial processes are discussed in areas of hydrocarbon separation, drying gases and liquids, separation and purification of industrial streams, pollution control, and nonregenerative applications. Special emphasis is placed on important commercial processes and potentially important applications. Important properties of zeolite adsorbents for these applications are adsorption capacity and selectivity, adsorption and desorption rate, physical strength and attrition resistance, low catalytic activity, thermal-hydrothermal and chemical stabilityy and particle size and shape. Apparent bulk density is important because it is related to adsorptive capacity per unit volume and to the rate of adsorption-desorption. However, more important factors controlling the raJtes are crystal size and macropore size distribution. [Pg.311]

Because of their electrical, optical, and redox properties as well as the thermal and chemical stability, the Pcs also have been tried in the detection of volatile organic compounds and poisonous gases, which is very important for environment and human health. In the past decades, the possible applications of Pc thin film as sensor for atmospheric gaseous pollutants have been extensively studied [73, 74], Langmuir-Blodgett films of some multinuclear and multidouble-decker lutetium Pcs have also been used for those measurements [75,76], More details about conductivity and sensing properties of Pcs can be found elsewhere [77,78]. [Pg.131]


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See also in sourсe #XX -- [ Pg.204 ]




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