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Proper functions

As a result of a variable liquid-junction potential, the measured pH may be expected to differ seriously from the determined from cells without a liquid junction in solutions of high acidity or high alkalinity. Merely to affirm the proper functioning of the glass electrode at the extreme ends of the pH scale, two secondary standards are included in Table 8.14. In addition, values for a 0.1 m solution of HCl are given to extend the pH scale up to 275°C [see R. S. Greeley, Anal. Chem. 32 1717 (I960)] ... [Pg.931]

Relaxation is an important example of a creep phenomenon encountered in practice. Bolts, studs, flanges, and springs of all kinds are subject to relaxation when used at high temperatures. These members are loaded to a stress that must be maintained for proper functioning. If relaxation occurs, the stress decreases. Thus bolts can become loose so that bolted joints develop leaks after operation at elevated temperatures. [Pg.112]

Iron is indispensable in the human body (see Mineral nutrients). The average adult body contains 3 grams of iron. About 65% is found in hemoglobin, which carries oxygen from the lungs to the various parts of the body. Iron is also needed for the proper functioning of cells, muscles, and other tissues (4). [Pg.412]

The hulls are the first material removed from the process to merit concern in respect to safeguards. These represent a possible route for special nuclear material (SNM) to be clandestinely removed from the system. Special instmmentation is used to assay the hulls containers for residual SNM. This step not only monitors the dissolver for proper functioning, but also serves an accountancy function as a material access area portal and enables the satisfaction of contractual requirements regarding process losses (40). [Pg.206]

Many misconceptions exist about cascade control loops and their purpose. For example, many engineers specify a level-flow cascade for every level control situation. However, if the level controller is tightly tuned, the out-flow bounces around as does the level, regardless of whether the level controller output goes direcdy to a valve or to the setpoint of a flow controller. The secondary controller does not, in itself, smooth the outflow. In fact, the flow controller may actually cause control difficulties because it adds another time constant to the primary control loop, makes the proper functioning of the primary control loop dependent on two process variables rather than one, and requites two properly tuned controllers rather than one to function properly. However, as pointed out previously, the flow controller compensates for the effect of the upstream and downstream pressure variations and, in that respect, improves the performance of the primary control loop. Therefore, such a level-flow cascade may often be justified, but not for the smoothing of out-flow. [Pg.70]

Nutrition. Zinc is essential to the proper functioning of plants and animals and, as zinc sulfate and oxide, it is used as a feed supplement (49—51) (see Mineral nutrients Feedsand feed additives). Most crops use less than a kilogram of zinc per 1000 m per year, so that zinc salts added at 1.3—4.5 kg/ha gradually build up the zinc reserve (52). Animals, including humans, store relatively Htde available zinc and, thus, require a constant supply in the diet. For instance, beef cattle require 10—30 mg/kg dry feed, dairy cattle 40 mg/kg, and breeding hens 65 mg/kg. Zinc from plants is considered less available to monogastric aminals than zinc from animal protein. [Pg.423]

One system for measuring catalyst failure is based on two oxygen sensors, one located in the normal control location, the other downstream of the catalyst (102,103). The second O2 sensor indicates relative catalyst performance by measuring the abiUty to respond to a change in air/fuel mixture. Other techniques using temperatures sensors have also been described (104—107). Whereas the dual O2 sensor method is likely to be used initially, a criticism of the two O2 sensors system has been reported (44) showing that properly functioning catalysts would be detected as a failure by the method. [Pg.491]

The first concern in designing process capable products is to guarantee the proper functioning of the product, and therefore to satisfy technical constraints. Dimensional... [Pg.6]

Thirty percent of the tumor-derived mutations are in L3, which contains the single most frequently mutated residue, Arg 248. Clearly the interaction between DNA and the specific side chain of an arginine residue inside the minor groove is of crucial importance for the proper function of p53. It is an open question whether this interaction is needed for the recognition of specific DNA sequences, or is required for the proper distortion of the DNA structure, or a combination of both. Other residues that are frequently mutated in this region participate in interactions with loop L2 and stabilize the structures of loops L2 and L3. Mutations of these residues presumably destabilize the structure so that efficient DNA binding can no longer take place. [Pg.171]

To provide for the proper functioning of the coil condenser even in warm weather it is advisable to increase the number of turns to 30-40, although the condenser as shown is satisfactory with tap water at 4-10°. [Pg.28]

The British Standard also uses the Assigned Protection Eactor, i.e. tlie level of respiratory protection that can realistically be expected to be achieved in the workplace by 95% of adequately trained and supervised workers, using a properly functioning and correctly fitted respiratory protective device (see Table 13.9)... [Pg.433]

Is all equipment designed to totally contain the materials which might be present inside at ambient temperature or the maximum attainable process temperature (i.e., don t rely on the proper functioning of external systems such as refrigeration systems to control temperature such that vapor pressure is less than equipment design pressure) ... [Pg.135]

Maintenance of electrical potential between the cell membrane exterior and interior is a necessity for the proper functioning of excitable neuronal and muscle cells. Chemical compounds can disturb ion fluxes that are essential for the maintenance of the membrane potentials. Fluxes of ions into the cells or out of the cells can be blocked by ion channel blockers (for example, some marine tox-... [Pg.282]

The standard requires that the supplier identify those characteristics of the design that are crucial to the safe and proper functioning of the product. [Pg.254]

The lists of critical items that were described under Identifying controls in Part 2 Chapter 2, together with Failure Modes and Effects Analysis and Hazard Analysis, are techniques that aid the identification of characteristics crucial to the safe and proper functioning of the product. [Pg.255]

Section 27.21 Often the catalytically active functions of an enzyme are nothing more than proton donors and proton acceptors. In many cases a protein acts in cooperation with a coenzyme, a small molecule having the proper functionality to cany out a chemical change not otherwise available to the protein itself. [Pg.1152]

The event tree model is started from the initial occurrence and built upon by sequencing tlie possible events and safety systems tliat come into play. Tlie model displays at a glance, branches of events tliat relate tlie proper functioning or failure of a safety device or s) Stem and tlte ultimate consequence. [Pg.505]

Moreover organophosphoric acid esters have found application as insecticides (e.g. Parathion). Some derivatives are highly toxic to man (e.g. Sarin, Soman). The organophosphonates act as inhibitors of the enzyme cholinesterase by phosphorylating it. This enzyme is involved in the proper function of the parasympathetic nervous system. A concentration of 5 x 10 g/L in the air can already cause strong toxic effects to man. [Pg.16]

Eigen-farbstoff, m. self-dye, self-color, -form, /. characteristic form, true form, -frequenz, /. proper, characteristic, or natural frequency, -funktion, /. proper function, characteristic function, eigenfunktion. -gewicht, n. [Pg.116]

Except as a limited reference, computer programs are not emphasized anywhere in these volumes. Instead, important mechanical details are given to emphasize the mechanical application of the process requirements (see Figure 2-2). Many of these details are essential to the proper functioning of the process in die hardware. For two fundamental aspects of fluid flow, see Figures 2-1 and 2-3. [Pg.52]

The opening provided through the disk, after burst, is sufficient to permit a flow equal to the capacity of the valve (Par. 2 and 3 above) and there is no chance of interference with proper functioning of the valve but in no case shall this area be less than 80% of the area of the inlet of the valve unless the capacity and functioning of the specific combination of rupture... [Pg.424]

For conventional valves, pressure drop or variations in back pressure should not exceed 10% of set pressure. Because most process safety valves are sized for critical pressure conditions, the piping must accommodate the capacity required for valve relief and not have the pressure at the end of vent or manifold exceed the critical pressure. Designing for pressure 30% to 40% of critical w ith balanced valves, yields smaller pipes yet allows proper functioning of the valve. The discharge line size must not be smaller than the valve discharge. Check the manufacturer for valve performance under particular conditions, especially with balanced valves w hich can handle up to 70% to 80% of set pressure as back pressure. [Pg.431]

Warm up engines and check the proper functioning of all machinery to assure that there will be no malfunctions that would result in sudden braking or jarring of the mast. Mast travel, once begun, must be slow, smooth, and continuous. [Pg.521]

The low conductivity of high-purity water makes it difficult to study electrode processes potentiostatically, since too high an electrical resistance in the circuit can affect the proper functioning of a potentiostat, and it can also introduce large iR errors. The increase in conductivity of water with temperature has been measured and /7 -corrected polarisation data have been obtained in hot water that originally had very low conductivity at room temperature. Other results in high-temperature water are all for tests where the conductivity was deliberately increased through the addition of electrolytes. [Pg.1120]

The previous section introduced the backpropagation rule for multi-layer percep-trons. This section briefly discusses tfie model development cycle necessary ftu-obtaining a properly functioning net. It also touches upon some of the available heuristics for determining the proper size of hidden layers. [Pg.546]


See other pages where Proper functions is mentioned: [Pg.502]    [Pg.385]    [Pg.185]    [Pg.157]    [Pg.28]    [Pg.471]    [Pg.30]    [Pg.1131]    [Pg.18]    [Pg.250]    [Pg.110]    [Pg.163]    [Pg.170]    [Pg.618]    [Pg.881]    [Pg.991]    [Pg.176]    [Pg.233]    [Pg.208]    [Pg.302]    [Pg.1456]    [Pg.426]    [Pg.996]    [Pg.148]    [Pg.432]   
See also in sourсe #XX -- [ Pg.305 ]




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