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Closed under operations

Packed vs Plate Columns. Relative to plate towers, packed towers are more useful for multipurpose distillations, usually in small (under 0.5 m) towers or for the following specific appHcations severe corrosion environment where some corrosion-resistant materials, such as plastics, ceramics, and certain metaUics, can easily be fabricated into packing but may be difficult to fabricate into plates vacuum operation where a low pressure drop per theoretical plate is a critical requirement high (eg, above 49,000 kg/(hm ) (- 10, 000 lb/(hft )) Hquid rates foaming systems or debottlenecking plate towers having plate spacings that are relatively close, under 0.3 m. [Pg.174]

We first generalize the nomenclature. Consider a Euclidean d-dimensional lattice L, with translation group Gp. A frame, F, of L is defined to be a finite subset of (not necessarily contiguous) sites of L that is closed under (i) intersection, (ii) union, (iii) difference and (iv) operations g Gp. A block, Bp, is a specific assignment... [Pg.258]

It is noted that two successive symmetry transformations of a system leave that system invariant. The product of the two operations is therefore also a symmetry operation of the system. The set of symmetry transformations is therefore closed under the law of successive transformations. An identity transformation that leaves the system unchanged clearly belongs to the set. It is not difficult to see that any given symmetry transformation has an inverse that also belongs to the set. Since successive transformations of the set obey the associative law it finally follows that the set constitutes a group. [Pg.57]

The binary operation ( multiplication ) in the Lie algebra is that of taking the commutator. As usual, we denote the commutator by square brackets, [A, fi] = AB- BA. A set of operators A is a Lie algebra when it is closed under commutation. That is, for every operator X in the algebra G (which we write as X e G)... [Pg.21]

Now, if a suitable space of basis functions is used (a space of basis functions that is closed under the symmetry operations of the group), we can construct a set of representations (each one consisting of 48 matrices) for this space that is particularly useful for our purposes. It is especially relevant that the matrices of each one of these representations can be made equivalent to matrices of lower dimensions. [Pg.240]

Otherwise, it would mean that there are at least two subspaces of the space of eigenfunctions fi,..., 4>i, - , 0gn, each of them closed under the symmetry operations of G. This would mean that there are no symmetry operations connecting these two subspaces, in spite of the fact that they have the same energy This, of course, seems to be unreasonable except in the case of accidental coincidence of two energy levels. [Pg.246]

To supplement the SVD analysis, rigorous d mamic simulations under closed loop operation were carried out. For the closed-loop analysis, several issues must be defined first, such as the control loops for each system, the type of process controller to be used, and the values of the controller parameters. [Pg.63]

The Board has noted that, in each of the above-mentioned cases involving stopped shipments, brokers had placed the orders. While the activities of brokers have been closely examined under Operation Purple, their activities have not been scrutinized under Operation Topaz. The Board therefore requests the Steering Committee of Operation Topaz to work with participating countries to make a comprehensive evaluation of the role brokers are playing in the diversion and subsequent smuggling of acetic anhydride. [Pg.22]

The fact that the product of any two of the four covering operations of the water molecule is again one of the four can be expressed by the statement that the set E, C2,(Jv, and covering operations of an object forms its symmetry group. [Pg.8]

A comparison of market penetration with the similar Responsible Care Model shows that more than 50% (in terms of value) of the chemical companies had implemented this new model after a period of 13 years. The Responsible Care Model, under which the chemical supplier ensures that "its" chemical is used in a way that is as environmentally friendly and protective of health as possible, is based on a similar idea and is comparable in nature. However, Responsible Care by no means requires such a close co-operation between the chemical supplier and the chemical user, and unlike Chemical Leasing, does not aim at minimising the volume of chemical substances used. By analogy, it can be expected that Chemical Leasing will have been adopted by half of the target customers, or approx. 2,000 SMEs, within roughly 10 years.9 Based on this, a diffusion curve (see appendix) was drawn up, which results in the following project demand for the first four years (Fig. 15.)... [Pg.190]

Earth and biology are in a non-equilibrium state, but maintains a steady state, for which it is an important condition that the system is not closed but oper to the outside. Only under open conditions can such non-equilibrium but steady state be maintained. If earth were closed, all biological life would end, but the Earth is fortunately open to the universe. Based on tnis as well as on the first and thu second laws of thermodynamics, it was a natural consequence that we humans confronted the problem of environment and energy resource only as far as wt conduct energy cycles in the closed earth It is important for our future energy resources that the earth be open to the universe, i.e., ro the sun. [Pg.337]

In addition to the three temperature levels (TP, MTSR, and TD24), there is another important temperature that at which technical limits of the equipment are reached. This may be due to the resistance of construction materials, or to the reactor design parameter as pressure or temperature, and so on. In an open reacting system, operated at atmospheric pressure, the boiling point is often used. In a closed system, operated under pressure, it may be the temperature on reaching the set pressure of the pressure relief system. [Pg.67]

In order to broaden the data base of the limestone DA process and to evaluate the impacts of closed-loop operation, a series of pilot plant tests was conducted under the sponsorship of U.S. Environmental Protection Agency s (EPA) Industrial Environmental Research Laboratory in Research Triangle Park, NC (IERL-RTP). The testing concentrated on evaluating the effects of magnesium and chloride ions since appreciable accumulations of soluble salts containing these two species are expected in a limestone DA system under closed-loop operating conditions. [Pg.182]

In the presence of a H-Y zeolite with a Si/Al ratio of 15, we have performed the hydrolysis of other fructose and glucose precursors under operating conditions quite close to those used for sucrose hydrolysis. It was found that aqueous solutions of inulin, maltose, cellobiose and starch (50-l20gL L) were hydrolysed into the corresponding monosaccharides within 30-150 min at temperatures between 90 °C and 150 °C in the presence of 0.5-2.5 g of catalyst in 50 ml of starting solution, with yields of monosaccharides from 92 to 98%.[12]... [Pg.143]

SAXS techniques offer a number of advantages for the characterization of porous materials [79-81] (1) they are sensitive to both closed and open porosity, (2) SAXS intensity profiles are sensitive to shape and orientation of the scattering objects, (3) they can be used to investigate samples that are saturated with liquids, and (4) they can be used to investigate the pore texture of materials under operating conditions. However, the equipment required for SAXS experiments is not as available as other adsorption equipment. [Pg.143]

Thus, they are closed under commutation and form a three-dimensional Lie algebra. By taking the appropriate linear combinations of these operators we can obtain operators satisfying the so(2, 1) defining commutation relations,... [Pg.30]

To perform its functions under this Convention, the IAEA set up, at its headquarters in Vienna, an Emergency Response Center (ERC) for receiving, collating, and rapidly transmitting relevant information. Close co-operation with the World Meteorological... [Pg.324]


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See also in sourсe #XX -- [ Pg.42 ]




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Closed operators

Operator closing

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