Articles

Since the invention of the jet engine and its use in the aerospace industry, the aim has always been to increase turbine operating temperatures since this means better efficiency, more power, less fuel consumption and less pollution for airplanes. Researchers investigate the foaming possibilities and processes of the ultra-high temperature alloys. This porous structure will be known as Refractory Open Cell Metal Foam.

A new material is tested to cut the weight of ships by 30 percent. For an average sized freight vessel with a capacity of 7000 m³ this corresponds to a weight reduction of more than 1000 tons. Researchers from Fraunhofer Institute for Machine Tools and Forming Technology in Chemnitz, Germany, have experimented with an aluminum powder that foams when heated up.

Ozone is toxic to the respiratory tract and ocular mucosa following inhalation exposure. As would be expected, the primary target of airborne ozone is the lung, and it is also shown to cause adverse effects on the eye and nervous system. Accordingly, ozone has long been recognized as one of the hazardous air pollutants, and one of the criteria air pollutants.

Photocatalytic oxidation (PCO) first saw use as a technique for water purification. However, due to the inherent inefficiency of the process (the need to filter out the TiO₂ after purification), techniques had to be developed to immobilise TiO₂ onto support surfaces. This has lead to a technology that lends itself to air purification.

For many high temperature processes like combustion and reforming systems a couple of high performance alloys has been developed for semi finished products e. g. sheets, rods or tubes. Metallic foams with their high porosity are now candidates for catalyst carriers and filters in high temperature and corrosive environment.

In industries where flammable mixtures are present flame arresters are used to prevent flame propagation in the event of ignition. Ceramic foam is typically used for gas filters or flame holders but also represents a novel material that can be used for flame arrester applications. The interconnectivity of the foam pores form a matrix of tortuous narrow passageways that the flame is forced to pass through, where flame extinction can occur.

Environmental catalysis refers to catalytic technologies for reducing emissions of environmentally unacceptable compounds. Problems addressed in regard to these catalytic cleanup technologies are mobile emission control, NO_x removal from stationary sources, sulfur compounds and VOCs (volatile organic compound) conversion.

Pollution decomposition is a very important ecological problem. That is why it demands the complex approach.Benzpyrene is the chemical carcinogen of environment.It is very dangerous chemical compound for people even at small concentrations.