One-cycle processes

B. Extract Ans with Lns in an extraction stage of high acidity and strip only Ans in a stripping stage. Lns must be kept in an organic phase under the Ans-strip conditions. Finally, Lns are stripped. This is a one-cycle process. 

One-Cycle Processes Separation of An(III) from PUREX Raffinates... 

One-cycle processes, which allow the separation of An(III) from Ln(III) directly from PUREX raffinates... 

Historically, pairs of processes have been developed throughout the world to achieve An(III)/Ln(III) partitioning TRUEX + TALSPEAK in the United States, TRPO + CYANEX in China, DIDPA + DIDPA in Japan, and DIAMEX + BTP or DIAMEX + ALINA in Europe, but cross combinations of processes are possible. The one-cycle processes (e.g., SETFICS and DIAMEX-SANEX/HDEHP) appear more attractive and more compact than the two-cycle processes, as they do not use two different solvent loops to carry out the separation of An(III) from Ln(III), but they sometimes generate much larger aqueous streams than the feed input. 

All of the substances necessary for PCR are present throughout and proceeding from one cycle to the next requires only changing the temperature after suitable time inter vals The entire process is carried out automatically and 30 cycles can be completed within a few hours... 

Onc-Factor-at-a-Timc Optimization One approach to optimizing the quantitative method for vanadium described earlier is to select initial concentrations for ITiOz and 1T2S04 and measure the absorbance. We then increase or decrease the concentration of one reagent in steps, while the second reagent s concentration remains constant, until the absorbance decreases in value. The concentration of the second reagent is then adjusted until a decrease in absorbance is again observed. This process can be stopped after one cycle or repeated until the absorbance reaches a maximum value or exceeds an acceptable threshold value. 

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. 

The required result can be written ZiA Z( T)) but since we now have a process very much akin to that of substituting one cycle index in another — the process by which the cycle index of a wreath product is obtained — it is usual to use the notation of the wreath product and write Z(y4j)[Z( T )]. 

Solvent Extraction. A modified, one-cycle PUREX process is used at Rocky Flats to recover plutonium from miscellaneous Pu-U residues (11). The process utilizes the extraction of uranium (VI) into tributyl phosphate (TBP), leaving plutonium (III) in the raffinate. The plutonium is then sent to ion exchange for... 

The availability of a metal describes one aspect of its potential to cycle among biogeochemical reservoirs. The initiation of the cycling process is called mobilization. Metals may be mobilized, that is, made available for transport away from their region of deposition, when the geochemi-... 

The three cycles have to turn over in the same range of temperature. This catalytic approach of the DeNOx reaction is not new. There is the same process for isomerization of alkanes, where there are also 3 catalytic cycles which have to turn over simultaneously (bifunctional catalysis). The kinetics of isomerization is given by only one cycle, the other two turning over very rapidly and are near equilibrium [13]. 

Thus, in one cycle, eight hydrogen atoms (H+ + e ) are transferred to hydrogen-transmitting coenzymes and later oxidized to water in the respiratory chain. This process is linked to oxidative phosphorylation, i.e., the synthesis of ATP from ADP and inorganic phosphate. 

The first reaction is a fusion of two protons to produce a 2H nucleus, a positron (e+) and a neutrino (ve). The second reaction is a proton capture with the formation of 3He and a y-ray. In the third reaction two 3He nuclei fuse to give 4He and two protons. The total energy released in one cycle is 26.8 MeV or 4.30 x 10-12 J. An important product of this process is the neutrino and it should provide a neutrino flux from the Sun that is measurable at the surface of the Earth. However, the measured flux is not as big as calculated for the Sun - the so-called neutrino deficit... 

CGCC [Coal Gasification, Combined Cycle] A general name for processes that both gasify coal and produce electricity. One such process has been operated by Louisiana Gasification Technology, at Plaquemine, LA, since 1987. See also APAC. 

In many types of processes such as batch constant-pressure filtration or fixed-bed ion exchange, the production rate decreases as a function of time. At some optimal time /opt, production is terminated (at P°pt) and the equipment is cleaned. Figure E4.12a illustrates the cumulative throughput P(t) as a function of time t for such a process. For one cycle of production and cleaning, the overall production rate is... 

Integrate nutrient removal in SBR is successfully achieved similarly as in continuous flow systems. It requires multiple fill and react phases during one cycle, with successive periods of aeration and anaerobic or anoxic mixing. It is claimed (Artan et al. 2001), that no biological conversion is assumed to occur during settle, draw and idle phases. The processes take... 

Figure 12.3 is a plot of the sodium sulphate content in the ion-exchange resin resulting from one cycle through the RNDS process. 

Figure 12.6 shows a scheme of the laboratory equipment used to test this set-up. Figure 12.7 is an example of the iodate concentration versus bed volume (BV) plot during one cycle of the adsorption-desorption process. Figure 12.8 shows the influence of the resin size on the extent of iodate removal. The particle size of the resin greatly influences the removal. The fluidised bed volume increases as the diameter of the resin reduces. 

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