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Short period

Find a way to overcome the constraint while still maintaining the areas. This is often possible by using indirect heat transfer between the two areas. The simplest option is via the existing utility system. For example, rather than have a direct match between two streams, one can perhaps generate steam to be fed into the steam mains and the other use steam from the same mains. The utility system then acts as a buffer between the two areas. Another possibility might be to use a heat transfer medium such as a hot oil which circulates between the two streams being matched. To maintain operational independence, a standby heater and cooler supplied by utilities is needed in the hot oil circuit such that if either area is not operational, utilities could substitute heat recovery for short periods. [Pg.184]

The objective of any exploration venture is to find new volumes of hydrocarbons at a low cost and in a short period of time. Exploration budgets are in direct competition with acquisition opportunities. If a company spends more money finding oil than it would have had to spend buying the equivalent amount in the market place there is little Incentive to continue exploration. Conversely, a company which manages to find new reserves at low cost has a significant competitive edge since it can afford more exploration, find and develop reservoirs more profitably, and can target and develop smaller prospects. [Pg.15]

Neural network classifiers. The neural network or other statistical classifiers impose strong requirements on the data and the inspection, however, when these are fulfilled then good fully automatic classification systems can be developed within a short period of time. This is for example the case if the inspection is a part of a manufacturing process, where the inspected pieces and the possible defect mechanisms are well known and the whole NDT inspection is done in repeatable conditions. In such cases it is possible to collect (or manufacture) as set of defect pieces, which can be used to obtain a training set. There are some commercially available tools (like ICEPAK [Chan, et al., 1988]) which can construct classifiers without any a-priori information, based only on the training sets of data. One has, however, always to remember about the limitations of this technique, otherwise serious misclassifications may go unnoticed. [Pg.100]

The layer width is taken from the relation d > 1,5 dg, where dg - thickness of a gas discharge gap. The employment of a resistive layer instead of electrode profiling can significantly simplify the device manufacture. The UV radiation is efficiently converted into a visible one by a number of photo-luminophors, e.g. Zn2Si04 Mn. For stroboscopic registration of fast-proceeding processes the luminophors with short period of luminescence are used, e.g anthracene etc. [Pg.540]

Due to the pulsed radiation output of the LINAC the detectors and the detector electronics have to handle very high counting rates in very short periods. Therefore the detectors have to work in a mode, where the detector output is integrated for one or several beam pulses. For that purpose the crystals are coupled to photo- diodes. Their currents are read out and analysed by the electronic board, which has been developed for this special application. [Pg.585]

Note that the van der Waals forces tliat hold a physisorbed molecule to a surface exist for all atoms and molecules interacting with a surface. The physisorption energy is usually insignificant if the particle is attached to the surface by a much stronger chemisorption bond, as discussed below. Often, however, just before a molecule fonus a strong chemical bond to a surface, it exists in a physisorbed precursor state for a short period of time, as discussed below in section AL7.3.3. [Pg.294]

Reference to the modern periodic table (p. (/)) shows that we have now completed the first three periods—the so-called short periods. But we should note that the n = 3 quantum level can still accommodate 10 more electrons. [Pg.8]

The periodic table also contains horizontal periods of elements, each period beginning with an element with an outermost electron in a previously empty quantum level and ending with a noble gas. Periods 1, 2 and 3 are called short periods, the remaining are long periods Periods 4 and 5 containing a series of transition elements whilst 6 and 7 contain both a transition and a rare earth senes,... [Pg.12]

The editor provides two modes for drawing the structure and the draw mode. This distinction is important for differentiating chemical information from conventional drawings. Both modes are switchable and provide an extensive set of features in the menu bar to create chemical structures and reactions, or just drawings. The number of options can be quite confusing for beginners however, one becomes accustomed to them after a short period of vocational adjustment. [Pg.141]

B) Semicarbazones. These often form readily in the cold (see above) if not, employ a reasonably short period of heating, othervvise carbazide, ( NH CO-NH2)2, m.p. 244°, may beformed and may separate. [Pg.343]

Use approximately 0 5 ml. of glycerol, and cork the flask A securely when weighing the glycerol by difference, owing to the very hygroscopic nature of the latter. Heat on the water-bath for 60 minutes instead of 30 minutes. Excellent results are obtained by this method if a freshly opened sample of anhydrous glycerol is available a sample which has been exposed to the air for even a short period will absorb sufficient water to give inaccurate results. [Pg.452]

The procedure whereby a Iktle alcohol is rapidly added to the vessel, supported in the funae chamber and containing some concentrated nitric acid, although generally preceded by a short period of induction, may be extremely dangerous and should not be used. Under no circumstances should concentrated nitric acid be euided to ethyl alcohol—a violent explosion may result. [Pg.54]

Two extractions usually sufiSce, but if much organic material remains, a third extraction should be made. If the p-iodoaniline from the second and third extractions is coloured, it should be refluxed for a short period in light petroleum solution with a little decolourising carbon and filtered through a hot water funnel (CA U TION inflammable). [Pg.647]

In those cases where stirring for short periods is necessary, this may usually be accomphshed by gentle rotation of the vessel thus imparting a swirhng motion to its contents. If the vessel cannot conveniently be moved, a hand-operated stirrer constructed entirely of glass (compare Fig. II, 10, 4 and Fig. II, 10, 2) will be found satisfactory provided the glass loop is not too large. [Pg.1108]

Exposure to manganese dusts, fume, and compounds should not exceed the ceiling value of 5 mg/ms for even short periods because of the element s toxicity level. [Pg.60]

With short periods of irradiation (with high-pressure mercury lamps) under oxygen in chloroform containing methylene blue as a sensitizer, variously substituted 2-arylthiazoles are converted in the corresponding 2-aryloxazoles (823). [Pg.309]

If Restart is not checked then the velocities are randomly assigned in a way that leads to a Maxwell-Boltzmann distribution of velocities. That is, a random number generator assigns velocities according to a Gaussian probability distribution. The velocities are then scaled so that the total kinetic energy is exactly 12 kT where T is the specified starting temperature. After a short period of simulation the velocities evolve into a Maxwell-Boltzmann distribution. [Pg.313]

Therefore, if a large quantity of sample is introduced into the flame over a short period of time, the flame temperature will fall, thus interfering with the basic processes leading to the formation and operation of the plasma. Consequently introduction of samples into a plasma flame needs to be controlled, and there is a need for special sample-introduction techniques to deal with different kinds of samples. The major problem with introducing material other than argon into the plasma flame is that the additives can interfere with the process of electron formation, a basic factor in keeping the flame self-sustaining. If electrons are removed from the plasma by... [Pg.97]

If solid samples are vaporized quickly, then the sample enters the flame as a small plug and the elements must be measured over a short period of time. This mode is useful for high sensitivity because the entire sample passes through the flame in a short time. (The abundances of ions appear as a sharp peak on the output.) If samples are introduced continuously, then ultimate sensitivity may be reduced, but isotope ratios can be determined continuously to provide high accuracy. [Pg.398]


See other pages where Short period is mentioned: [Pg.90]    [Pg.63]    [Pg.300]    [Pg.5]    [Pg.12]    [Pg.34]    [Pg.301]    [Pg.585]    [Pg.1720]    [Pg.2803]    [Pg.83]    [Pg.603]    [Pg.21]    [Pg.291]    [Pg.297]    [Pg.389]    [Pg.525]    [Pg.541]    [Pg.1006]    [Pg.17]    [Pg.47]    [Pg.238]    [Pg.59]    [Pg.1216]    [Pg.643]    [Pg.98]    [Pg.104]    [Pg.109]    [Pg.110]    [Pg.163]    [Pg.363]   
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See also in sourсe #XX -- [ Pg.33 ]

See also in sourсe #XX -- [ Pg.8 ]

See also in sourсe #XX -- [ Pg.72 ]




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