Masonry heater

          A masonry heater (or masonary stove, ceramic stove, tile stove) is a device for warming an interior space by capturing the heat from periodic burning of fuel (usually wood), and then radiating the heat at a fairly constant temperature for a long period . The technology has existed in different forms: from the Roman hypocaust to the Austrian/German kachelofen. The hypocaust is a system for heating the floors and walls of buildings (especiallybaths) using the smoke and exhaust of a single fire. In Eastern and Northern Europe and North Asia, these kachelofens (or steinofens) evolved in many different forms and names: for example the Russian Stove/Fireplace (Russian: Русская печь), the Finnish Stove (in Finnish: pystyuuni or kaakeliuuni, "tile oven") and the Swedish Stove (in Swedish: kakelugn, "tile stove" or "contra-flow stove") associated with Carl Johan Cronstedt. The Chinese developed the same principle into their Kang bed-stove. The masonry heater has gained renewed domestic popularity recently because of its heating efficiency.


Thank for Info : http://en.wikipedia.org

Porcelain tile

          Porcelain tiles are ceramic tiles with a water absorption rate of less than 0.5 percent that are used to cover floors and walls. They can either be unglazed or glazed.

          The hardness of the tile is rated from zero to five according to the ASTM C1027 (or ISO 10545-7) test for surface abrasion resistance of glazed tile. This rating, (sometimes mistakenly called the PEI rating) determines the tiles suitability for various end use conditions.

          Large-scale production of porcelain tile is undertaken in many countries, with the major producers being China, Italy, Spain and Turkey. There are also countries undertaking small-scale production, such as Australia and strong growth in developing countries such as Brazil.

         Porcelain Tile is also a very common trend in tile installation. There are many different styles of porcelain tiles on the market and they have proved to outperform ceramic tile in durability and looks.

          It is important to note that the differences of the body of the porcelain tile, as it relates to ceramic tile, has caused many "job failures" of tile installations. Tile setters that are self trained and novices to the industry will often use cements or mastic to install the impervious body of the porcelain tile to a substrate only to have delamination occur rather quickly. Highly Modified cements are necessary for installation of this material due to the very qualities that make it such a durable long lasting decorative surface. Those specifications are determined by and dictated as industry standards by the Tile Council of America, and supported by the Tile Contractors Association.

Thank for Info : http://en.wikipedia.org

High temperature insulation wool

          In the 1950s, the term “Refractory Ceramic Fibre” was coined for the aluminium silicate fibres developed at this time. On account of their chemical purity and resistance to high temperatures (classification temperature >1000 °C) as well as on the basis of their use in other applications, this definition was made to differentiate aluminium silicate wools from the conventional “mineral wools”. Because of the ambiguity of the term “ceramic” and the development of new materials for the high temperature range, the nomenclature was changed to High Temperature Insulation Wool (HTIW) at the end of the 1990s.

          Basically, there are two types of inorganic HTIW. In addition to the more commonly used amorphous HTIW (Alumino Silicate Wool ASW/RCF and Alkaline Earth Silicate Wool (AES)), Polycrystalline Wool (PCW) is also available. Owing to the costly production and limited availability compared to mineral wool, HTIW products are almost only used in industrial applications and processes up to 1800 °C.

Thank for Info : http://en.wikipedia.org

Silicon nitride

          Silicon nitride is a chemical compound of silicon and nitrogen. If powdered silicon is heated between 1300 °C and 1400 °C in an atmosphere of nitrogen, trisilicon tetranitride, Si₃N₄ is formed. The silicon sample weight increases progressively due to the chemical combination of silicon and nitrogen. Without an iron catalyst, the reaction is complete after several hours (~7), when no further weight increase due to nitrogen absorption (per gram of silicon) is detected. In addition to Si₃N₄, several other silicon nitride phases (with chemical formulas corresponding to varying degrees of nitridation/Si oxidation state) have been reported in the literature, for example, the gaseous disilicon mononitride (Si₂N); silicon mononitride (SiN), and silicon sesquinitride (Si₂N₃), each of which are stoichiometric phases. As with other refractories, the products obtained in these high-temperature syntheses depends on the reaction conditions (e.g. time, temperature, and starting materials including the reactants and container materials), as well as the mode of purification. However, the existence of the sesquinitride has since come into question.

The Si₃N₄ phase is the most chemically inert (being decomposed by dilute HF and hot H₂SO₄). It is also the most thermodynamically stable of the silicon nitrides. Hence, Si₃N₄ is the most commercially important of the silicon nitrides and is generally understood as what is being referred to where the term "silicon nitride" is used.

          Silicon nitride (i.e. Si₃N₄) is a hard ceramic having high strength over a broad temperature range, moderate thermal conductivity, low coefficient of thermal expansion, moderately high elastic modulus, and unusually high fracture toughness for a ceramic. This combination of properties leads to excellent thermal shock resistance, ability to withstand high structural loads to high temperature, and superior wear resistance. Silicon nitride is mostly used in high-endurance and high-temperature applications, such as gas turbines, car engine parts, bearings and metal working and cutting tools. Silicon nitride bearings are used in the main engines of the NASA's Space shuttles. Thin silicon nitride films are a popular insulating layer in silicon-based electronics and silicon nitride cantilevers are the sensing parts of atomic force microscopes.

Thank for Info : http://en.wikipedia.org

Refractory metals

          Refractory metals are a class of metals that are extraordinarily resistant to heat and wear. The expression is mostly used in the context of materials science, metallurgy and engineering. The definition of which elements belong to this group differs. The most common definition includes five elements: two of the fifth period (niobium andmolybdenum) and three of the sixth period (tantalum, tungsten, and rhenium). They all share some properties, including a melting point above 2000 °C and high hardness at room temperature. They are chemically inert and have a relatively high density. Their high melting points make powder metallurgy the method of choice for fabricatingcomponents from these metals. Some of their applications include tools to work metals at high temperatures, wire filaments, casting molds, and chemical reaction vessels in corrosive environments. Partly due to the high melting point, refractory metals are stable against creep deformation to very high temperatures.


Thank for Info : http://en.wikipedia.org

Oil shale

Oil shale

          Oil shale, also known as kerogen shale, is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons called shale oil (not to be confused with tight oil—crude oil occurring naturally in shales) can be produced. Shale oil is a substitute for conventional crude oil; however, extracting shale oil from oil shale is more costly than the production of conventional crude oil both financially and in terms of its environmental impact. Deposits of oil shale occur around the world, including major deposits in the United States of America. Estimates of global deposits range from 2.8 to 3.3 trillion barrels (450×10⁹ to 520×10⁹ m³) of recoverable oil.

          Heating oil shale to a sufficiently high temperature causes the chemical process of pyrolysis to yield a vapor. Upon cooling the vapor, the liquid shale oil—an unconventional oil—is separated from combustible oil-shale gas (the term shale gas can also refer to gas occurring naturally in shales). Oil shale can also be burnt directly in furnaces as a low-grade fuel for power generation and district heating or used as a raw material in chemical and construction-materials processing.

          Oil shale gains attention as a potential abundant source of oil whenever the price of crude oil rises. At the same time, oil-shale mining and processing raise a number of environmental concerns, such as land use, waste disposal, water use, waste-water management, greenhouse-gas emissions and air pollution. Estonia and China have well-established oil shale industries, and Brazil, Germany, Russia also utilize oil shale.

          Oil shales differ from oil-bearing shales, shale deposits which contain petroleum (tight oil) that is sometimes produced from drilled wells. Examples of oil-bearing shales are the Bakken Formation, Pierre Shale, Niobrara Formation, and Eagle Ford Formation.

Thank for Info : http://en.wikipedia.org

Thermal insulation

Thermal insulation

          Thermal insulation is the reduction of heat transfer between objects in thermal contact or in range of radiative influence. Heat transfer is the transfer of thermal energy between objects of differing temperature. The means to stem heat flow may be especially engineered methods or processes, as well as suitable static objects and materials.

Heat flow is an inevitable consequence of contact between objects of differing temperature. Thermal insulation provides a means to maintain a gradient of temperature, by providing a region of insulation in which heat flow is reduced or thermal radiation is reflected rather than absorbed.

          In building construction, insulating materials are assigned a quantitative measure of the insulating capability, called the R-value.

         In thermal engineering of insulating systems for ovens, reactors, and furnaces, thermal conductivity (K), product density and specific heat (C) are the key product characteristics, which influence insulating efficiency, such as acolodet insulating.

Low thermal conductivity (K) is analogous to high insulating capability (R).

          Aerogels, microporous silica and ceramic fiber insulation are three best performing insulators for applications between 200 Celsius and 2000 Celsius. Zirconia fibers have the lowest thermal conductivity of all ceramic fiber products and are used in applications up to 2000 Celsius.

Thank for Info : http://en.wikipedia.org

Filtration

Filtration

         Filtration is commonly the mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size and filter thickness). Filtration is also used to describe some biological processes, especially in water treatment and sewage treatment in which undesirable constituents are removed by absorption into a biological film grown on or in the filter medium.


Thank for Info : http://en.wikipedia.org

Building insulation

          Building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is forthermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation (e.g. for vibrations caused by industrial applications). Often an insulation material will be chosen for its ability to perform several of these functions at once.


Thank for Info : http://en.wikipedia.org

High-temperature material

         Silicon nitride has long been used in high-temperature applications. In particular, it was identified as one of the few monolithic ceramic materials capable of surviving the severe thermal shock and thermal gradients generated in hydrogen/oxygen rocket engines. To demonstrate this capability in a complex configuration, NASA scientists used advanced rapid prototyping technology to fabricate a one-inch-diameter, single-piece combustion chamber/nozzle (thruster) component. The thruster was hot-fire tested with hydrogen/oxygen propellant and survived five cycles including a 5-minute cycle to a 1320 °C material temperature.

Thank for Info : http://en.wikipedia.org

Putty

          Putty is a generic term for a plastic material similar in texture to clay or dough typically used in domestic construction and repair as a sealant or filler.Painter's Putty is typically a linseed oil based product used for filling holes, minor cracks and defacements in wood only. Putties can also be madeintumescent, in which case they are used for firestopping as well as for padding of electrical outlet boxes in fire-resistance rated drywall assemblies. In the latter case, hydrates in the putty produce an endothermic reaction to mitigate heat transfer to the unexposed side.


Thank for Info : http://en.wikipedia.org

Epoxy putty

          Epoxy putty is a room-temperature-hardening substance used as a space-filling adhesive. It is stored until use as two components of clay-like consistency. Kneading the two components into each other creates an exothermic chemical reaction that activates the substance for use by catalyzing an epoxide polymerisation reaction. Unlike many other types of glues, an epoxy adhesive can fill gaps and even be molded into a structural part. Some makers claim in advertising that one can tap and drill their cured product, and that it quickly cures "hard as steel" (as measured by Shore rating), though it is much weaker than steel in tensile strength and shear strength.


Thank for Info : http://en.wikipedia.org

Adhesive

Adhesive

          Adhesion is the tendency of dissimilar particles or surfaces to cling to one another (cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are certain emergent mechanical effects that will also be discussed at the end of the article


Thank for Info :http://en.wikipedia.org

Hot-melt adhesive

Hot-melt adhesive

        Hot melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly supplied in solid cylindrical sticks of various diameters, designed to be melted in an electric hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which may be pushed through the gun by a mechanical trigger mechanism, or directly by the user. The glue squeezed out of the heated nozzle is initially hot enough to burn and blister skin. The glue is tacky when hot, and solidifies in a few seconds to one minute. Hot melt adhesives can also be applied by dipping or spraying. This was invented by Miles Kent in 1894.

          In industrial use, hot melt adhesives provide several advantages over solvent-based adhesives. Volatile organic compounds are reduced or eliminated, and the drying or curing step is eliminated. Hot melt adhesives have long shelf life and usually can be disposed of without special precautions. Some of the disadvantages involve thermal load of the substrate, limiting use to substrates not sensitive to higher temperatures, and loss of bond strength at higher temperatures, up to complete melting of the adhesive. This can be reduced by using a reactive adhesive that after solidifying undergoes further curing e.g. by moisture (e.g. reactive urethanes and silicones), or is cured by ultraviolet radiation. Some HMAs may not be resistant to chemical attacks and weathering. HMAs do not lose thickness during solidifying; solvent-based adhesives may lose up to 50-70% of layer thickness during drying.

Thank for Info : http://en.wikipedia.org

High temperature co-fired ceramic

          High temperature co-fired ceramic (HTCC) is a multi-layer packaging technology for the electronics industry, used in military electronics, MEMS, microprocessor and RF applications.HTCC packages generally consist of multilayers of alumina oxide with tungsten and molymanganese metalization. 
          The ceramic is fired at around 1600 degrees Celsius, which is significantly higher than a similar technology Low temperature co-fired ceramic, or LTCC. Compared to LTCC, HTCC has higher resistance conductive layers.
 Advantages of HTCC includes mechanical rigidity and hermeticity, both of which are important in high-reliability and environmentally stressful applications. Another advantage is HTCC's thermal dissipation capability, which makes this a microprocessor packaging choice, especially for higher performance processors.