Redistribution index

Two parameters, the redistribution index (Uts) and the reduced partitioning parameter (IR), are used to describe the redistribution processes of trace elements in contaminated arid soils (Figs. 6.5-6.6) (Han et al., 2003a). The redistribution index depicts the removal or attainment of element-contaminated soils from or to the fractional distribution pattern characteristic of non-amended soils. However, the reduced partitioning parameter quantifies the relative binding intensity of trace elements in soils. 

Comonomer is exhausted at relatively low conversion (20), but a random copolymer is nevertheless obtained. This is because a very facile transacetalisation reaction allows for essentially random redistribution of the comonomer units (18) and also results in a polydispersity index near 2.0 (21). 

Photorefractivity is a property exhibited by some materials in which the redistribution in space of photogenerated charges will induce a nonuniform electric space-charge field which can, in turn, affect the refractive index of the material. In a new material the active species is a highly efficient cyclopalladated molecule97,98 shown in Figure 5. The palladium-bonded azobenzene molecule is conformationally locked, and gratings derived from cis—trans isomerizations can be safely excluded. 

Table 6.5. Reduced partition index (IR) of trace metals in arid-zone soils incubated under saturated paste regime (after Han and Banin, 1997. Reprinted from Water Air Soil Pollut, 95, Han F.X., Banin A., Long-term transformations and redistribution of potentially toxic heavy metals in arid-zone soils. I Incubation under saturated conditions, p 411, Copyright (1997), with permission from Springer Science and Business Media)...

Figure 6.7. Ranges (arithmetic mean and standard deviation) of the reduced partition index (IR) of Cd, Cu, Cr, Ni and Zn in 45 Israeli arid-zone soils (after Han et al., 2003a. Reprinted from Adv Environ Res, 8, Han F.X., Banin A., Kingery W.L., Triplett G.B., Zhou L.X., Zheng S.J., Ding W.X., New approach to studies of redistribution of heavy metals in soils, p 118, Copyright (2003), with permission from Elsevier)...

Minimize Coupling (Dependencies). The list of collaborations should be small. The well-known CRC technique of detailing responsibilities and collaborations on a single index card gives some idea of their preferred sizes. If the list is too large, suspect that a redistribution of responsibilities is required. 

The photorefractive effect is the term used for the changes induced in the refractive index of a material by a redistribution of photogenerated charges. 

However, one anomalous feature of this technique is that there occurs an apparent rapid removal of material from the concentration gradient at the boundary, as evidenced by a reduction in the area under the Schlieren curve. For the standard PVP/dextran T10 system, we observed a reduction of 20 % during the 10 min after the formation of the initial boundary no further changes in the area occurred after this initial event. This reduction in area is not accompanied by the appearance of refractive index gradients elsewhere in the cell47 . The redistribution of material within the cell has been shown to occur by monitoring PVP 360 directly using absorption optics at 237 nm. 

Small bubbles and flow uniformity are important for gas-liquid and gas-liquid-solid multiphase reactors. A reactor internal was designed and installed in an external-loop airlift reactor (EL-ALR) to enhance bubble breakup and flow redistribution and improve reactor performance. Hydrodynamic parameters, including local gas holdup, bubble rise velocity, bubble Sauter diameter and liquid velocity were measured. A radial maldistribution index was introduced to describe radial non-uniformity in the hydrodynamic parameters. The influence of the internal on this index was studied. Experimental results show that The effect of the internal is to make the radial profiles of the gas holdup, bubble rise velocity and liquid velocity radially uniform. The bubble Sauter diameter decreases and the bubble size distribution is narrower. With increasing distance away from the internal, the radial profiles change back to be similar to those before contact with it. The internal improves the flow behavior up to a distance of 1.4 m. 

In severe lead poisoning sodium calciumedetate is commonly used to initiate lead excretion. It chelates lead from bone and the extracellular space and urinary lead excretion of diminishes over 5 days thereafter as the extracellular store is exhausted. Subsequently symptoms (colic and encephalopathy) may worsen and this has been attributed to redistribution of lead from bone to brain. Dimercaprol is more effective than sodium calciumedetate at chelating lead from the soft tissues such as brain, which is the rationale for combined therapy with sodium calciumedetate. More recently succimer (2,3-dimercaptosuccinic acid, DMSA), a water-soluble analogue of dimercaprol, has been increasingly used instead. Succimer has a high affinity for lead, is suitable for administration by mouth and is better tolerated (has a wider therapeutic index) than dimercaprol. It is licenced for such use in the USA but not the UK. 

This effect occurs when the frequency of the incident beam is near a resonant energy transition of the atom or molecule that is responsible for the nonlinear behavior. Near the resonance the electrons occupy a real excited state for a finite period of time. For low intensity light, the population redistribution results in a change of the index of reflection, since it is mostly determined by the molecules in the ground state. A typical value for population redistribution susceptibility is x 10 esu, with a time response 10 s. 

As an example of sensor applications, for an optical fiber with a core diameter 20 pm, ciad = 1.45, and core = 1.46, the field of the modal power forLP/ modes is shown in Fig. 28a,b for the modal orders I = 6 and /= 13, at an optical wavelength X = 0.75 pm. In the presence of external perturbations applied to the fiber, resulted in changing the cladding index to ciad = 1.455, the modal power redistribution of Z = 6 and / = 13 modes is shown in Fig. 28c, d. This theoretical analysis is based on the use of a single frequency (laser) light source. 

For example, a step index silica hber of 100-pm-diameter was excited at 10° off-axis. The 2D far-held pattern (MPD) and intensity prohle were scanned and recorded by a CCD camera as shown in Fig. 30a. When the hber was under perturbation, the recorded far-held pattern showed intermodal coupling and redistribution of the modal power (Fig. 30b). As the perturbation level was increased, considerable rearrangement of the modal power was recorded in a similar way. This experiment indicates that continuous variation of the applied perturbation results in a respective change in the MPD, in a very sensitive manner. 

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