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Specification value

W, g potential functions, k 1, has been discussed in various papers (see, for example, [6, 11, 9, 16, 3]). It has been pointed out that, for step-sizes /j > e = 1/ /k, the midpoint method can become unstable due to resonances [9, 16], i.e., for specific values of k. However, generic instabilities arise if the step-size k is chosen such that is not small [3, 6, 18], For systems with a rotational symmetry this has been shown rigorously in [6j. This effect is generic for highly oscillatory Hamiltonian systems, as argued for in [3] in terms of decoupling transformations and proved for a linear time varying system without symmetry. [Pg.282]

In many chemical applications, however, it would be more interesting to know how polarizability can stabilize a charge introduced into a molecule. Thus, rather than the global molecular property, mean molecular polarizability, a local, site-specific value for polarizability is needed. [Pg.333]

When a specific value above is n ot hn own, the rule of Pauling (the van der Waals radius is approximately 0.76 A larger than the cova-len t radiiis) is u sed. [Pg.213]

Atom types represent the chemical environment of an atom. The atom types associated with a given force field could be hard-wired to have specific values and meaning. HyperChem also allows flexible definitions of the atom types and the associated chemical environments. The chemical environment of an atom (a set of rules for defining a type) and the default rules are in a standard ASCII text file, chem.rul, included with HyperChem. You can modify this file and compile it in a binary form that HyperChem... [Pg.170]

The temperature at which AG changes sign (i.e., where AG = 0) is given by the ratio AH/AS if these quantities are independent of T. The temperature at which rings become favored depends on the specific values of AH and AS, and, again, this is a matter of ring size. [Pg.329]

For 1 = 6 the contribution of AH° is unfavorable and that of AS° is favorable. The specific values make T = 298 K very close to the equilibrium temperature. This implies that the reaction is shifted to favor polymer at higher temperatures and to favor the cyclic monomer at lower temperatures. Since the difference between AH° and T AS° is so small, the temperature dependence of AH° and AS° could alter this conclusion. [Pg.330]

At the other end of the commonly encountered range we find the product rjr2 1. As noted above, this limit corresponds to ideal copolymerization and means the two monomers have the same relative tendency to add to both radicals. Thus if rj = 10, monomer 1 is 10 times as likely to add to Mj- than monomer 2. At the same time r2 = 0.1, which also means that monomer 1 is 10 times as likely to add to M2 than monomer 2. In this case the radicals exert the same influence, so the monomers add at random in a proportion governed by the specific values of the r s. [Pg.433]

The equations we have written until now in this section impose no restrictions on the species they describe or on the origin of the interaction energy. Volume and entropy effects associated with reaction (8.A) will be less if x is not too large. Aside from this consideration, any of the intermolecular forces listed above could be responsible for the specific value of x- The relationships for ASj in the last section are based on a specific model and are subject to whatever limitations that imposes. There is nothing in the formalism for AH that we have developed until now that is obviously inapplicable to certain specific systems. In the next section we shall introduce another approximation... [Pg.523]

Pollutants. The problems posed by ak pollutants are very serious. Within a museum, measures can be taken to remove harmful substances as efficiently as possible by means of the installation of appropriate filter systems in the ventilation equipment. Proposed specification values for museum climate-control systems requke filtering systems having an efficiency for particulate removal in the dioctyl phthalate test of 60—80%. Systems must be able to limit both sulfur dioxide and nitrogen dioxide concentrations <10 /ig/m, and ozone to <2 /ig/m. ... [Pg.429]

Corrective action should be initiated when value is > — 0.23 V against the standard hydrogen electrode (SHE). Plant-specific values should be estabUshed for protection of stainless steels and nickel-based critical components. [Pg.195]

Specification values and items may vary with different manufacturers. Analytical methods may be obtained from manufacturers. [Pg.8]

In order to operate a process facility in a safe and efficient manner, it is essential to be able to control the process at a desired state or sequence of states. This goal is usually achieved by implementing control strategies on a broad array of hardware and software. The state of a process is characterized by specific values for a relevant set of variables, eg, temperatures, flows, pressures, compositions, etc. Both external and internal conditions, classified as uncontrollable or controllable, affect the state. Controllable conditions may be further classified as controlled, manipulated, or not controlled. Excellent overviews of the basic concepts of process control are available (1 6). [Pg.60]

Sig nifica.ntDig lts. Any digit that is necessary to define the specific value or quantity is said to be significant. A problem arises, however, when a value of, eg, 4 in. is given. This may be intended to represent 4, 4.0, 4.00, 4.000 or even more accuracy with a corresponding increase in significant digits (equivalent to 102, 101.6, 101.60, and 101.600 mm, respectively). [Pg.311]

The activity of P-lactamase inhibitors is often expressed as an IC q value, which is defined as the concentration of inhibitor that causes 50% inhibition of en2yme activity for a given set of conditions. IC q values, which vary widely according to substrate, time of incubation, and other factors, are presented herein solely to give an indication of potency and en2yme inhibitor specificity. Values that decrease with preincubation are indicative of irreversible inhibitors. [Pg.46]

Phenolics are consumed at roughly half the volume of PVC, and all other plastics are consumed in low volume quantities, mosdy in single apphcation niches, unlike workhorse resins such as PVC, phenoHc, urea—melamine, and polyurethane. More expensive engineering resins have a very limited role in the building materials sector except where specific value-added properties for a premium are justified. Except for the potential role of recycled engineering plastics in certain appHcations, the competitive nature of this market and the emphasis placed on end use economics indicates that commodity plastics will continue to dominate in consumption. The apphcation content of each resin type is noted in Table 2. Comparative prices can be seen in Table 5. The most dynamic growth among important sector resins has been seen with phenoHc, acryUc, polyurethane, LLDPE/LDPE, PVC, and polystyrene. [Pg.331]

In addition to surface area, pore size distribution, and surface chemistry, other important properties of commercial activated carbon products include pore volume, particle size distribution, apparent or bulk density, particle density, abrasion resistance, hardness, and ash content. The range of these and other properties is illustrated in Table 1 together with specific values for selected commercial grades of powdered, granular, and shaped activated carbon products used in Hquid- or gas-phase appHcations (19). [Pg.529]

Specific values shown are those cited in manufacturers product Hterature (19). Typical ranges shown are based on values reported in the open Hterature. [Pg.530]

The solution to this equation requites an initial condition (n 2itt = 0) and a boundary condition (n at a specific value of T). Assuming that crystals are formed at zero size gives the boundary condition ... [Pg.355]

A regulator is a compact device that maintains the process variable at a specific value in spite of disturbances in load flow. It combines the functions of the measurement sensor, controher, and final control element into one self-contained device. Regulators are available to control pressure, differential pressure, temperature, flow, hquid level, and other basic process variables. They are used to control the differential across a filter press, heat exchanger, or orifice plate. Regulators are used for monitoring pressure variables for redundancy, flow check, and liquid surge relief. [Pg.793]

Extracted from the Chemical Plant and Petroleum Refinery Piping Code, ANSI B31.3—1980, with permission of the publisher, the American Society of Mechanical Engineers, New York. Individual compounds may vary from the values in the table by as much as 10 percent. Consult manufacturers for specific values for their products. [Pg.1004]

Values of critical moisture contents for some representative materials are given in Table 12-7 for diying by cross circulation and in Table 12-15 for diying by through circulation. The tabulated values are only approximate, since critic moisture content depends on the drying histoiy. It appears that the constant-rate period ends when the moisture content at the surface reaches a specific value. Since the critical... [Pg.1181]

The rotor speed of the scaled up tower is based on maintaining the same specific power input number as used on the pilot column it can be determined by substituting the specific values into the relationship ... [Pg.1482]

The second reason for modification of the displaced volume is that in real world application, the cylinder will not achieve the volumetric performance predicted by Equation 3.4. It is modified, therefore, to include empirical data. The equation used here is the one recommended by the Compressed Air and Gas Institute [1], but it is somewhat arbitrary as there is no universal equation. Practically speaking, however, there is enough flexibility in guidelines for the equation to produce reasonable results. The 1.00 in the theoretical equation is replaced with. 97 to reflect that even with zero clearance the cylinder will not fill perfectly. Term L is added at the end to allow for gas slippage past the piston rings in the various types of construction. If, in the course of making an estimate, a specific value is desired, use, 03 for lubricated compressors and. 07 for nonlubricated machines. These are approximations, and the exact value may vary by as much as an additional. 02 to. 03... [Pg.57]

Employing an iterative computer program, in conjunction with the above equations, Katz et al. examined a wide range of values for (k) and (Vmw) nd calculated the volume change on mixing of a series of methanol/water mixtures having assumed volume fractions of methanol. The results for each selected values of (k) and (Vmw) and each volume fraction of methanol were compared with experimentally determined values of (vj) and the specific values of (k) and (Vmw) that gave the minimum error... [Pg.127]

The MTZ is that length of the adsorbent bed where the adsorbate concentration in the liquid varies from the influent concentration to zero or the specification value. At the same contact time, the single fixed-bed system at the higher LV stays onstream about 15 percent longer. [Pg.308]

For reports submitted for calendar years 1987, 1988, and 1989 only, you may take advantage of range reporting for releases to an environmental medium that are less than 1,000 pounds forthe year. If you choose this option, mark one of the three boxes, 0, 1-499, or 500-999, that corresponds to releases of the chemical to the appropriate environmental medium (i.o., any line item). You are not required, however, to use these range check boxes you have the option of providing a specific value in column A.2, as described below. However, gg not mark a range and also enter a specific estimate in A.2. [Pg.42]

It should be noted that although Table 1.8 gives specific values of Tg for different polymers, in reality the glass-transition temperature is not a material constant. As with many other properties of polymers it will depend on the testing conditions used to obtain it. [Pg.30]


See other pages where Specification value is mentioned: [Pg.23]    [Pg.23]    [Pg.385]    [Pg.49]    [Pg.233]    [Pg.119]    [Pg.290]    [Pg.525]    [Pg.219]    [Pg.7]    [Pg.428]    [Pg.196]    [Pg.196]    [Pg.145]    [Pg.314]    [Pg.298]    [Pg.454]    [Pg.1601]    [Pg.2352]    [Pg.164]    [Pg.330]    [Pg.543]    [Pg.135]   
See also in sourсe #XX -- [ Pg.398 ]




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Alloys specific heat values

Case II Temperature-Dependent Specific Heat Values

Ceramics specific heat values

Enantiomers, specificity, range values

Fibers specific heat values

Fracture specific values

Limit values Specifications for the leak detector

Metals specific heat values

Nominal specification value

Polymers specific heat values

Specific Heat Values

Specific Impulse Values

Specific conductivity values

Specific gravity selected values

Specific rate function experimental values

Specific resistance value

Specific value

Specificity value

Writing specificity, value

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