Fast furnace

In exceptional, very fast furnaces, where power on times are typically less than 30 minutes per heat, there is some evidence that the zinc may be partially dissolved in the steel bath and might ultimately result in problems while casting. However, this problem is very rare and in the vast majority of cases no effect is seen. 

EH Larsen. Graphite furnace atomic absorption spectrometry of inorganic and organic arsenic species using conventional and fast furnace programmes. J Anal At Spectrom 6 375-377, 1991. 

Because of its small size and portabiHty, the hot-wire anemometer is ideally suited to measure gas velocities either continuously or on a troubleshooting basis in systems where excess pressure drop cannot be tolerated. Furnaces, smokestacks, electrostatic precipitators, and air ducts are typical areas of appHcation. Its fast response to velocity or temperature fluctuations in the surrounding gas makes it particularly useful in studying the turbulence characteristics and rapidity of mixing in gas streams. The constant current mode of operation has a wide frequency response and relatively lower noise level, provided a sufficiently small wire can be used. Where a more mgged wire is required, the constant temperature mode is employed because of its insensitivity to sensor heat capacity. In Hquids, hot-film sensors are employed instead of wires. The sensor consists of a thin metallic film mounted on the surface of a thermally and electrically insulated probe. 

Validation and Application. VaUdated CFD examples are emerging (30) as are examples of limitations and misappHcations (31). ReaUsm depends on the adequacy of the physical and chemical representations, the scale of resolution for the appHcation, numerical accuracy of the solution algorithms, and skills appHed in execution. Data are available on performance characteristics of industrial furnaces and gas turbines systems operating with turbulent diffusion flames have been studied for simple two-dimensional geometries and selected conditions (32). Turbulent diffusion flames are produced when fuel and air are injected separately into the reactor. Second-order and infinitely fast reactions coupled with mixing have been analyzed with the k—Z model to describe the macromixing process. 

SAF = super abrasion furnace ISAF = intermediate super abrasion furnace HAF = high abrasion furnace FEF = fast extrusion furnace ... 

The binary scheme can be modified to suit any other requirement also. For example, for an induetion furnace, requiring very fast correction, the scheme may be modified, to have six stages in the ratio of 10 20 40 80 160 160 kVAr to make a total of 470 kVAr and correetions in steps of 10 kVAr each. 

Floating, single-speed with adjustable neutral zone Fast Any Small Processes with small dead time. Industrial furnaces and air conditioning... 

Fast extrusion furnace grade of carbon black. See Furnace Black. 

A type of carbon black produced by burning natural gas or oil in a large furnace with a supply of air much lower than that required for complete combustion. The main types are super abrasion (SAF), intermediate super abrasion (TSAF), high abrasion (HAF), fast extrusion (FEF), general purpose (GPF), conductive (CF) and semireinforcing (SRF). 

SAF - Super abrasion furnace, ISAF - Intermediate super abrasion HAF - High abrasion furnace, FEF - Fast extmsion furnace SRF - Semi reinforcing furnace HS - High structure, LS - low structure, HM - High modulus ... 

Fast-breeder reactors (FBR), 17 585-588 liquid-metal, 22 763 knowledge base for, 17 586 Fast color bases, 9 409—4 lOt Fast color salts,. 9 409-411 Fast-curing agents, 10 409-410 Fastening, ABS, 1 428 Fast extrusion furnace (FEF) blacks,... 

Si wafers were either cleaned in Piranha solution, washed with deionized water and dried with Ar gas, or used without cleaning. The samples were then inserted into the high temperature tube furnace. Since SAN can form extremely fast, we believe that SAN existed in all samples. When the furnace temperature was set between 1035 and 1100°C, SiNW were formed. 

This is frequently the required mode of operation for fast oxidation reactions because the heat release is too fast to provide efficient heat exchange. Most combustion processes are nearly adiabatic (your home furnace and your automobile engine), and many catalytic oxidation processes such as NH3 oxidation in HNO3 synthesis are nearly adiabatic. 

Q. Why are fast response electronics and background correction essential when using furnace... 

The West rod atomizers were marketed for a while, but their production has also ceased. These atomizers had the advantages of simplicity, low power requirements (less than half that required by a furnace) and fast heating rate (2000 K S l)- They were, however, considered to be extremely prone to interferences. This was attributed to the rapid cooling of the atoms once they had left the filament. This was partially overcome by setting the light beam so that it grazed the surface of the rod. 

The stabilized temperature platform furnace (STPF) concept was first devised by Slavin et al. It is a collection of recommendations to be followed to enable determinations to be as free from interferences as possible. These recommendations include (i) isothermal operation (ii) the use of a matrix modifier (iii) an integrated absorbance signal rather than peak height measurements (iv) a rapid heating rate during atomization (v) fast electronic circuits to follow the transient signal and (vi) the use of a powerful background correction system such as the Zeeman effect. Most or all of these recommendations are incorporated into virtually all analytical protocols nowadays and this, in conjunction with the transversely heated tubes, has decreased the interference effects observed considerably. 

Caution. During the heatup period the reaction tube may explode in the furnace if the temperature is raised too fast, if the tube has not been filled under strictly anhydrous conditions, or if the metal pentahalide is partially hydrolyzed. 

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