Assessment of the Acoustic Absorption Characteristics of Layered Composite Structures Obtained from Plates with Lignocellulosic Coatings (I)

Abstract

<jats:p> Abstract.The paper aims to present research on the determination of the coefficient of acoustic absorption as a function of frequency, for composite monolayer plates (made of: MDF - wooden dried agglomerated fibres with medium density, RWB - rebated wood from dried beech, PS - extruded polystyrene) and multilayer (with outer coatings of: MDF, RWB and polymeric core of extruded polystyrene). The sound-absorbing behavior of such plates is highlighted in the cabins made of multilayer structures. </jats:p>

Study Deformability Ecological Steel (41Cr4)

“…3). [8,9,11,12,21]. Figure 5 shows the appearance of micro rod with section 100 mm x 100 mm blum rolled continuously cast: are seen lamellar ferrite and pearlite.…”

“…A friendly technology with the environment which consists in the elaboration of carbon steels through specific proceedings to powder metallurgy has in view the contribution of methane gas in iron powders at the same time with sintering. This technology is advantageous from various points of view: the final product is a part which does not need afterward processing with solid waste result and therefore the specific energy consume is lower, the wear and corrosion behavior is similar to that of classic steels and better than that of sintered steels obtained through mixing iron and graphite; the obtained steels is also a recycling material [5,6,9]. The carbon steel obtained through this new technology is an ecomaterial, energy consumption and reduced environmental pollution [4,8,15].…”

Analysis of Comfort Indices and Their Impact on the Environment

“…The air conditioning aims to achieve the indoor environment that responds to the conditions of thermal comfort [15,18,19]. Indoor air quality and thermal comfort play a major role in the lives of the inhabitants [21,22,27].…”

Polluting Emissions from Incineration and Waste Installations

“…Incineration of urban waste is used to reduce waste disposal by storing them or recovering energy by burning. Incineration must comply with technical regulations to avoid adverse effects on human health and the environment [4,28,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43].…”