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Flow Sheet. Most purge-swing appHcations use two fixed-bed adsorbers to provide a continuous flow of feed and product (Fig. 16). Single beds are used when the flow to be treated is intermittent or cycHc. Because the purge flow is invariably greater than that of adsorption, purge is carried out in the down-flow direction to prevent bed lifting, and adsorption is up-flow. [Pg.284]

Gate oxide dielectrics are a cmcial element in the down-scaling of n- and -channel metal-oxide semiconductor field-effect transistors (MOSEETs) in CMOS technology. Ultrathin dielectric films are required, and the 12.0-nm thick layers are expected to shrink to 6.0 nm by the year 2000 (2). Gate dielectrics have been made by growing thermal oxides, whereas development has turned to the use of oxide/nitride/oxide (ONO) sandwich stmctures, or to oxynitrides, SiO N. Oxynitrides are formed by growing thermal oxides in the presence of a nitrogen source such as ammonia or nitrous oxide, N2O. Oxidation and nitridation are also performed in rapid thermal processors (RTP), which reduce the temperature exposure of a substrate. [Pg.348]

Tablet Press. The main components of a tablet compression machine (press) are the dies, which hold a measured volume of material to be compressed (granulation), the upper punches which exert pressure on the down stroke, and the lower punches which move upward after compaction to eject the tablets from the dies. Mechanical components deflver the necessary pressure. The granulation is fed from a hopper with a feed-frame on rotary-type presses and a feeding shoe on single-punch presses. A smooth and even flow ensures good weight and compression uniformity. Using the proper formulation, demixing in the hopper is minimized. Tablet Press. The main components of a tablet compression machine (press) are the dies, which hold a measured volume of material to be compressed (granulation), the upper punches which exert pressure on the down stroke, and the lower punches which move upward after compaction to eject the tablets from the dies. Mechanical components deflver the necessary pressure. The granulation is fed from a hopper with a feed-frame on rotary-type presses and a feeding shoe on single-punch presses. A smooth and even flow ensures good weight and compression uniformity. Using the proper formulation, demixing in the hopper is minimized.
Another method for estimating thixotropy involves the hysteresis of the thixotropic loop. The area of the thixotropic loop is calculated or measured, which works well with printing inks (3). In a variation of this method, the up curve on an undisturbed sample is deterrnined. The sample is then sheared at high shear (>2000 ) for 30—60 s, followed by deterrnination of the down curve (22). The data ate plotted as Casson-Asbeck plots, vs 7 / (14), as... [Pg.169]

A dimensionally stable anode consisting of an electrically conducting ceramic substrate coated with a noble metal oxide has been developed (55). Iridium oxide, for example, resists anode wear experienced ia the Downs and similar electrolytic cells (see Metal anodes). [Pg.167]

Energy Requirements. The energy requirements of several sodium manufacturiag processes are compared ia Table 7 (76). The data contain some ambiguities because of the allocation of energy to the coproduction of chlorine. An iadependent calculation shows a somewhat lower energy consumption for the Downs process (92). [Pg.167]

Lithium. Several processes for lithium [7439-93-2], Li, metal production have been developed. The Downs cell with LiCl—KCl electrolyte produces lithium ia much the same manner as sodium is produced. Lithium metal or lithium—aluminum alloy can be produced from a mixture of fused chloride salts (108). Granular Li metal has been produced electrochemically from lithium salts ia organic solvents (109) (see LiTHlUM AND LITHIUM compounds). [Pg.80]

Down spouts (or up spouts) are best set flush with the plate from which they lead, with no weir as in gas-hquid contact. The velocity of the continuous phase in the down spout V, which sets the down-spout cross section, should be set at a value lower than the terminal velocity of some arbitrarily small droplet of dispersed phase, say, 0.08 or 0.16 cm i M or Mfi in) in diameter otherwise, recirculation of entrained dispersed phase around a plate will result in flooding. The down spouts should extend beyond the accumulated layer of dispersed phase on the plate. [Pg.1480]

The head required for flow of continuous phase he includes losses due to (1) friction in the down spout, which should be negligible, (2) contraction and expansion upon entering and leaving the down spout, and (3) two abrupt changes in direction. These total 4.5 velocity heads ... [Pg.1480]

The distance between trays Zt should be larger than h, sufficient so that (1) the streamers of dispersed hquid from the holes break up into drops before coalescing into the layer of liqmd on the next plate, (2) the linear velocity of continuous liquid is not greater than that in the down out to avoid excessive entrainment, and (3) the tower may be enterea through handholes or manholes in the sides for cleaning. [Pg.1480]

The procedure for finding the maximum concentration and the down-wina distance for the maximum is to... [Pg.2343]

It seems likely, therefore, that as the bound phosphate molecule is released, the cleft starts to open and the myosin head binds to actin (Figure 14.17d). Release of ADP coincides with a conformational change that fully opens the myosin cleft, causing actin to be tightly bound, and moves the lever arm to the "down" position. Since the myosin head is now strongly bound to actin at one end and covalently linked to the myosin fibril at the other... [Pg.296]

In those application where the cross-coupling effects from the oil seal were detrimental to the rotor dynamics, the use of the gas seal is a dis tinct advantage. However, the down side is that should the oil seal ha c provided a good measure of damping, the impact on the rotor dynamics is reversed. None of this is irreversible, but certainly must be kept m mind at the time of design. [Pg.216]

For centrifugal compressors, nozzle orientation must be specified. If the compressor is on an elevated foundation, the down-nozzle orientation makes maintenance much easier, because major piping does not have to be removed to lift the casing upper half. Figure 11-1 shows an unusual case where all the nozzles are in the upper casing half. [Pg.446]

Assuming the down velocity of the stationary phase is (Ql) then if... [Pg.435]

Report the name of the down river water utility and the number of people served by it. [Pg.371]

Two or more plane jets can be placed above and outside the rim (all sides) of a canopy hood and directed downward. Fhe exhaust flow into the hood makes the down-directed jets turn inward and upward when the jet velocity has slowed down enough to be influenced by the exhaust flow. In many cases, the aim is to diminish the general supply airflow rate into the room and sometimes to use the jets as separators. lliis method is quite often used on large kitchen hoods to increase their capture efficiency. If the jet is directed toward the front of the fireplace and just reaches the front before turning inward, a high capture efficiency can be achieved. [Pg.1006]

Let the down time be t and assume that it is substantially independent of eake thiekness. The total time, T, of a eyele in whieh a volume V is eolleeted is then... [Pg.102]

Thus for the optimal operation of a bateh filter, the filtration time and the down time are equal. In praetiee t > t due to eloth resistanee, whieh is negleeted in this simple analysis. [Pg.102]

In the realistic case where the potential is spin-dependent, the spin-orbit method is in trouble (should the spin-orbit parameter be calculated with the up or the down spin potential ). The present formalism allows for the use of spin-dependent potential and wavefunctions. [Pg.454]

Newcomen engines continued to operate, especially in collieries, almost to the end of the eighteenth centuiy. Yet they, too, were wasteful. The way was open for a great advance, James Watt s invention in 1768 of the sepai atc condenser. Next to the driving cylinder stood another cylinder, exhausted and permanently cold. When the inoincnt for the down-stroke came, a valve opened, the steam rushed over and condensed the valve then closed and the cycle was repeated. The driving cylinder stayed permanently hot. [Pg.1031]

Adverse conditions with down draft - the down draft mixes with the products of combustion and diluted products enter the room for the brief period that the downdraft persists. The draft in the primary flue (and hence the performance of the appliance) is unaffected. [Pg.269]

For small appliances, the down draft diverter is often incorporated into them for larger appliances, it is external. [Pg.269]

If back-pressure is too low or demand too high, the compressor will be unable to provide sufficient volume or pressure to the down-stream systems. In this instance, the discharge pressure will be noticeably lower than designed. [Pg.561]

This type of compressor will continue to compress the air volume in the down-stream system until (1) some component in the system fails, (2) the brake horsepower exceeds the driver s capacity, or (3) a safety valve opens. Therefore, the operator s primary control input should be the compressor s discharge pressure. If the discharge pressure is below the design point, it is a clear indicator that the total down-stream demand is greater than the unit s capacity. If the discharge pressure is too high, the demand is too low and excessive unloading will be required to prevent failure. [Pg.561]

Always select the best bearing design for the application and not the cheapest. The cost of the original bearing is usually small by comparison to the costs of replacement components and the down-time in production when premature bearing failure occurs because an inappropriate bearing was used. [Pg.1020]

To retain fluidity of the catalyst and to maintain catalyst densities in the 35 to 45 Ib/ft (560-720 kg/m ) range (the fluid range), many standpipes require external aeration gas to be injected into the down-flowing... [Pg.240]

If jets are inclined at angles other than 90° to the flat plate, the overall mass transport appears to be unchanged except that the stagnation area is nearer to the down side of the jet . [Pg.319]

Polya s paper, translated here for the first time, was a landmark in the history of combinatorial analysis. It presented to mathematicians a unified technique for solving a wide class of combinatorial problems " a technique which is summarized in Polya s main theorem, the "Hauptsatz" of Section 16 of his paper, which will here be referred to as "Polya s Theorem". This theorem can be explained and expounded in many different ways, and at many different levels, ranging from the down-to-earth to highly abstract. It will be convenient for future reference to review the essentials of Polya s Theorem, and to this end I offer the following, rather mundane, way of looking at the type of problem to which the theorem applies and the way that it provides a solution. [Pg.96]


See other pages where The down is mentioned: [Pg.1450]    [Pg.122]    [Pg.161]    [Pg.369]    [Pg.189]    [Pg.69]    [Pg.165]    [Pg.167]    [Pg.169]    [Pg.311]    [Pg.76]    [Pg.545]    [Pg.80]    [Pg.1478]    [Pg.1479]    [Pg.2224]    [Pg.348]    [Pg.145]    [Pg.135]    [Pg.267]    [Pg.177]    [Pg.270]   
See also in sourсe #XX -- [ Pg.16 , Pg.23 , Pg.24 ]




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Accelerating leads down the funnel

Boiling down the Schrodinger equation

Break the Job Down into Steps

Breaking Down the Job

Breaking Down the Minimal Requirements

Breaking Down the Scope

Breaking down the problem

Conventions for writing down the electrochemical cell

Down the Rabbit Hole Pitfalls When Dealing with Low-Affinity Binders

Dynamics of the dipolar slowing-down process

Getting Down to the Wire

How does the Born-Oppenheimer approximation break down

Industrial rates and the scale-down problem

Nanotechnology The Top Down and Bottom Up Approaches

Preparation of Nanosuspensions Using the Bottom-Down Process

Projections down to a space spanned by the significant variables

Slowing-down Process in the Infinite Medium

THE UPS AND DOWNS OF BRIDGES

The Combined Slowing-down and Diffusion Equation

The Top-Down Approach to Functional Analysis

The Top-Down Design Process

Top-Down Derivation of the Components

Trends down the Groups

Turning Down the Dial of Life

Why is the Conventional Concordia Plot Concave Down

Why is the Holms-Houtermans Model Concave Down

Why is the U-Th-Pa Concordia Diagram Concave Down Everywhere

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