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Negative absorbance

PRINT "REMEMBER HEAT ENVOLVED POSITIVE HEAT ABSORBED NEGATIVE"... [Pg.89]

FOR EACH REACTION OR PHASE CHANGE INPUT THE HEAT OF REACTION OR THE LATENT HEAT, kJ/kmol AND QUANTITY INVOLVED kmol/h REMEMBER HEAT ENVOLVED POSITIVE HEAT ABSORBED NEGATIVE... [Pg.97]

Love philtre absorbs negativity from people while growing. Emblem of love floral perfume tobacco substitute brings good luck and a powerful force against magic. [Pg.70]

The function of fhe zone control system is to maintain a specified amount of reactivity in the reactor, this amount being determined by the deviation from the specified reactor power set point. If the zone control system is imable to provide the necessary correction, the program in the reactor regulating system draws on other reactivity control devices. Positive reactivity can be added by withdrawal of absorbers. Negative reactivity can be induced by insertion of mechanical control absorbers or by automatic addition of poison to the moderator. [Pg.155]

It is now possible to rearrange the activities based on the learned numbers to further increase the operative viability (e.g. by creating the parts list in parallel to creating the components list). Despite the fact that it would slow down the best case, this modification could decrease the time required when the upper path is taken. It would therefore increase the systems capacities to absorb negative effects as the upper part is essentially involved in the delayed cases. The time behavior and thus the resilience levels of the re-designed workflow are instantaneously available as no new data is required. [Pg.367]

The capacity of the damaged ecosystem or community to absorb negative impacts and recover from these... [Pg.2984]

For small concentrations of analyte, Pstray is significantly smaller than Pq and Py, and the absorbance is unaffected by the stray radiation. At higher concentrations of analyte, however, Pstray is no longer significantly smaller than Py and the absorbance is smaller than expected. The result is a negative deviation from Beer s law. [Pg.388]

The concentration of fluoride in drinking water may be determined indirectly by its ability to form a complex with zirconium. In the presence of the dye SPADNS, solutions of zirconium form a reddish colored compound, called a lake, that absorbs at 570 nm. When fluoride is added, the formation of the stable ZrFe complex causes a portion of the lake to dissociate, decreasing the absorbance. A plot of absorbance versus the concentration of fluoride, therefore, has a negative slope. [Pg.396]

Accuracy Under normal conditions relative errors of 1-5% are easily obtained with UV/Vis absorption. Accuracy is usually limited by the quality of the blank. Examples of the type of problems that may be encountered include the presence of particulates in a sample that scatter radiation and interferents that react with analytical reagents. In the latter case the interferant may react to form an absorbing species, giving rise to a positive determinate error. Interferents also may prevent the analyte from reacting, leading to a negative determinate error. With care, it maybe possible to improve the accuracy of an analysis by as much as an order of magnitude. [Pg.409]

The development of active ceramic-polymer composites was undertaken for underwater hydrophones having hydrostatic piezoelectric coefficients larger than those of the commonly used lead zirconate titanate (PZT) ceramics (60—70). It has been demonstrated that certain composite hydrophone materials are two to three orders of magnitude more sensitive than PZT ceramics while satisfying such other requirements as pressure dependency of sensitivity. The idea of composite ferroelectrics has been extended to other appHcations such as ultrasonic transducers for acoustic imaging, thermistors having both negative and positive temperature coefficients of resistance, and active sound absorbers. [Pg.206]

The nuclear chain reaction can be modeled mathematically by considering the probable fates of a typical fast neutron released in the system. This neutron may make one or more coUisions, which result in scattering or absorption, either in fuel or nonfuel materials. If the neutron is absorbed in fuel and fission occurs, new neutrons are produced. A neutron may also escape from the core in free flight, a process called leakage. The state of the reactor can be defined by the multiplication factor, k, the net number of neutrons produced in one cycle. If k is exactly 1, the reactor is said to be critical if / < 1, it is subcritical if / > 1, it is supercritical. The neutron population and the reactor power depend on the difference between k and 1, ie, bk = k — K closely related quantity is the reactivity, p = bk jk. i the reactivity is negative, the number of neutrons declines with time if p = 0, the number remains constant if p is positive, there is a growth in population. [Pg.211]

Control of the core is affected by movable control rods which contain neutron absorbers soluble neutron absorbers ia the coolant, called chemical shim fixed burnable neutron absorbers and the intrinsic feature of negative reactivity coefficients. Gross changes ia fission reaction rates, as well as start-up and shutdown of the fission reactions, are effected by the control rods. In a typical PWR, ca 90 control rods are used. These, iaserted from the top of the core, contain strong neutron absorbers such as boron, cadmium, or hafnium, and are made up of a cadmium—iadium—silver alloy, clad ia stainless steel. The movement of the control rods is governed remotely by an operator ia the control room. Safety circuitry automatically iaserts the rods ia the event of an abnormal power or reactivity transient. [Pg.240]


See other pages where Negative absorbance is mentioned: [Pg.1318]    [Pg.99]    [Pg.345]    [Pg.68]    [Pg.125]    [Pg.112]    [Pg.574]    [Pg.92]    [Pg.454]    [Pg.177]    [Pg.1043]    [Pg.1318]    [Pg.99]    [Pg.345]    [Pg.68]    [Pg.125]    [Pg.112]    [Pg.574]    [Pg.92]    [Pg.454]    [Pg.177]    [Pg.1043]    [Pg.201]    [Pg.432]    [Pg.115]    [Pg.67]    [Pg.188]    [Pg.257]    [Pg.21]    [Pg.2]    [Pg.137]    [Pg.387]    [Pg.770]    [Pg.240]    [Pg.13]    [Pg.236]    [Pg.20]    [Pg.414]    [Pg.440]    [Pg.442]    [Pg.452]    [Pg.455]    [Pg.467]    [Pg.451]    [Pg.49]    [Pg.52]    [Pg.469]    [Pg.403]   
See also in sourсe #XX -- [ Pg.189 , Pg.211 ]




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