Geometric concentration ratio

Radius of cylinder is equal to the half of the focal length and is equal to the width of solar module. In this case geometric concentration ratio equals ... 

A schematic presentation of an optical concentrator is given in Fig. 2.3. The shape of the system can be arbitrary, as well as its mechanism of focusing. The important factor of the system is its concentration ratio, defined as a ratio between the input (collector) area and the exit area. In an ideal concentration system, this ratio should be equal to the ratio of incident optical flux to the exit flux. In a real system, possible absorption losses (for instance in metal parts) will have to be deducted. Thus the concentration ratio of a light concentrator can be defined either as the geometric concentration ratio C, the ratio of the entry aperture area (AcoUector) to the exit aperture area (Aexit), or as the irradiance gain C the ratio of the irra-diance on the collector (fr ) to that on the entry aperture (Ir ). The two concentration terms are related by the fraction of total incident power entering the module that reaches the concentrator exit aperture. 

Antimalarial drugs There were lower concentrations of atovaquone -I- proguanil in HIV-infected individuals taking efavirenz. The authors compared the pharmacokinetics of atovaquone -I- proguanil between healthy volunteers and HIV-infected patients taking efavirenz and found that the geometric mean ratio AUCo x for... 

Gal-Or and Resnick (G8) measured average residence time in a system that was geometrically similar to those used by Cooper et al (C9) and Yoshida et al (Y4) with air-distilled water and air-sodium sulfite solutions of the same concentration as used by these investigators. The ratio of impeller to tank diameter was 0.4 in one series (as in the work of Cooper and Yoshida) and 0.3 in a second series. Gal-Or and Resnick reported their results as an average residence time in seconds per foot of gas-free liquid, Bh. The average residence time was calculated from the equation... 

The close-packed-spheron theory of nuclear structure may be described as a refinement of the shell model and the liquid-drop model in which the geometric consequences of the effectively constant volumes of nucleons (aggregated into spherons) are taken into consideration. The spherons are assigned to concentric layers (mantle, outer core, inner core, innermost core) with use of a packing equation (Eq. I), and the assignment is related to the principal quantum number of the shell model. The theory has been applied in the discussion of the sequence of subsubshells, magic numbers, the proton-neutron ratio, prolate deformation of nuclei, and symmetric and asymmetric fission. 

Chemical similarity exists between systems that show geometric, kinematic, dynamic, and thermal similarity, if concentration differences between corresponding points in the two systems have a constant ratio to one another. 

It is readily observed that the expression within brackets for the peak concentration C forms a geometric progression in which the first term equals one and with a common ratio of e . (The common ratio is the factor which results from dividing a term of the progression by its preceding one.) For the sum of the finite progression in eq. (39.41) we obtain after n cycles ... 

The dimensionless limiting current density N represents the ratio of ohmic potential drop to the concentration overpotential at the electrode. A large value of N implies that the ohmic resistance tends to be the controlling factor for the current distribution. For small values of N, the concentration overpotential is large and the mass transfer tends to be the rate-limiting step of the overall process. The dimensionless exchange current density J represents the ratio of the ohmic potential drop to the activation overpotential. When both N and J approach infinity, one obtains the geometrically dependent primary current distribution. 

In reality, extensive data by Medronho (Antunes and Medronho, 1992) indicate that the product Nst50NEu is not constant but depends on the ratio of underflow to feed (R) and the feed volumetric concentration (Cv) and NEu also depends on Cv as well as VRe. The Reitema and Bradley geometries are two common families of geometrically similar designs, as defined by the geometry parameters in Table 12-3 (Antunes and Medronho, 1992). 

An impurity in a water stream at a very small concentration is to be removed in a charcoal trickle bed filter. The filter is in a cylindrical column that is 2 ft in diameter, and the bed is 4 ft deep. The water is kept at a level that is 2 ft above the top of the bed, and it trickles through by gravity flow. If the charcoal particles have a geometric surface area to volume ratio of 48 in.-1 and they... 

The effect of crown ethers on the geometrical orientation in base-promoted E2 eliminations has been studied by several groups. Bartsch et al. (1973) have investigated the effect of several parameters on the potassium alkoxide-promoted eliminations of HBr from 2-bromobutane (Table 45). In the absence of crown ethers the relative amount of 1-butene formed increases, while the trans/cis ratio of the 2-butenes decreases, with decreasing solvent polarity. Furthermore, the proportion of 1-butene increases and the trans/cis ratio decreases on increasing the base concentration. These effects were explained in terms of steric interactions between the base and a- and /7-alkyl groups in the... 

Equivalent v-sites i have the same probability p, to be occupied by a dye molecule. The occupation probability p is equal to the ratio between the occupied and the total number of equivalent sites. The number of unit cells I1C is controlled by the host while ns is determined by the length of the guest, which means that p relies on purely geometrical (space-filling) reasoning and that the dye concentration per unit volume of a zeolite crystal can be expressed as a function of p as follows ... 

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