Mixing zone

Surface water Is usually undersaturated in calcium ions (Ca ). Where (even saturated) surface water mixes with sea water, mixing zone corrosion will dissolve calcium carbonate. Evidence of this occurring may be seen on islands. 

Eig. 6. Schematic ofTeclmicon CHEAl I analy2er where P = aspiration AIV = metering valves CT = capillary Teflon tube M = reagent mixing zone ... 

Often, complete mixing cannot be approached for economic reasons. Inactive or dead zones, bypassing, and limitations of energy input are common causes. Packed beds are usually predominantly used in plug flow reactors, but they may also have small mixing zones... 

The depth (thickness) of the mixing zone, which limits the depth resolution of a SIMS analysis typically to 2—30 nm, is a function of the energy, angle of incidence,... 

Because SIMS can measure only ions created in the sputtering process and not neutral atoms or clusters, the detection limit of a particular element is affected by how efficiently it ionizes. The ionization efficiency of an element is referred to as its ion yield. The ion yield of a particular element A is simply the ratio of the number of A ions to the total number of A atoms sputtered from the mixing zone. For example, if element A has a 1 100 probability of being ionized in the sputtering process—that is, if 1 ion is formed from every 100 atoms of A sputtered from the sample—the ion yield of A would be 1/100. The higher the ion yield for a given element, the lower (better) the detection limit. 

In commercial extruders, additional zones may be included to improve the quality of the output. For example there may be a mixing zone consisting of screw flights of reduced or reversed pitch. The purpose of this zone is to ensure uniformity of the melt and it is sited in the metering section. Fig. 4.4 shows some designs of mixing sections in extruder screws. 

Bach et al., Pozin, and Shilkrot and Zhivov - present two-zone models for mixing, zoning, and stratification strategies with different air distribution methods. 

The mass, momentum and energy balances for the mixing zone are... 

This principle is confined to domestic applications where kerosene or premium gas oil is concerned. The simplest type uses a number of concentrically arranged wicks which promote vaporization of kerosene into an air/vapor mixing zone enclosed within a perforated dmm arrangement. Normally, these burners obtain their air by natural draft. 

Increasing feed/catalyst mix zone temperature. Conversion and LPG yield can be increased by injecting a portion of the feed, or naphtha, at an intermediate point in the riser (see Figure 6-1). Splitting or segregation of the feed results in a high-mix zone temperature, producing more LPG and more olefins. This practice... 

Larger Zeolite Unit Cell Size AddZSM-5 Additive Higher Cat/Oil ratio Higher Mix Zone temperature Split Feed injection Riser Quench... 

The main mechanical conditions that affect octane are the type and condition of the feed nozzles. Low-efficiency feed nozzles actually increase the gasoline octane due to promotion of thermal reactions in the mix zone. High-efficiency feed nozzles improve feed/catalyst mixing and increase the gasoline yield, but decrease gasoline octane. 

Mix Zone Temperature is the theoretical equilibrium temperature between the regenerated catalyst and the uncracked vaporized feed at the bottom of I he riser. 

Many other plate designs are now available with specific functionaHties, and because of modular conception, it is possible to perform aU the steps required in a chemical reaction in various zones such mixing zone, residence time zone, and quench zone. 

The flow of jets becomes turbulent at much lower Re numbers than channel flows. Calculating the stress from the mean velocity profiles does not reflect the true situation in turbulent flow. As in the case in most bioreactors, the maximum turbulent stress is determined by the turbulence, which can be calculated using Eqs. (2)-(4). It occurs in free jets after the nozzle, at the edge of the mixing zone. The following is generally valid ... 

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