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Starting solutions

The connection between these functions and the microphysical properties of the layers can be found by returning to the original formal solutions of the transfer equation, Eqs. (2.2.3) and (2.2.4). If the layer is thin enough, the Planck intensity B is essentially constant throughout, and the diffuse field becomes vanishingly small. Hence term (4) in Eq. (2.2.3), and term (3) in Eq. (2.2.4), suffice to describe the emitted radiation fields in the upward and downward directions, respectively. Letting a o and B be independent of r (valid for a sufficiently thin layer), the solution for Eq. (2.2.3) becomes [Pg.49]

The solutions for the outgoing radiation fields are obtained by setting r = 0 in Eq. (2.3.17) and r = ti in Eq. (2.3.18). Thus the outgoing intensities emitted from a thin layer are [Pg.49]

These values can be used as starting values for /e in the repeated applications of Eqs. (2.3.7) through (2.3.10). [Pg.49]

On the other hand, the solution to Eq. (2.2.3) for a thin layer in the presence of an outside point source of radiation is given by [Pg.49]

Upon letting r = 0, the solution for the upwelling radiation field is  [Pg.49]


Chlorine gas is usually used, but electrolysis of alkaline salt solutions in which chlorine is generated in situ is also possible and may become more important in the future. The final pH of solutions to be sold or stored is always adjusted above 11 to maximize stabiUty. The salt is usually not removed. However, when the starting solution contains more than 20.5% sodium hydroxide some salt precipitates as it is formed. This precipitate is removed by filtration to make 12—15% NaOCl solutions with about one-half of the normal amount of salt. Small amounts of such solutions are sold for special purposes. Solutions with practically no salt can be made by reaction of high purity hypochlorous acid with metal hydroxides. [Pg.143]

Fig. 14. CD-spectra of alternating (L-Leu-L-Lys) in water-methanol mixtures at different pH of the starting solution "2-"9)... Fig. 14. CD-spectra of alternating (L-Leu-L-Lys) in water-methanol mixtures at different pH of the starting solution "2-"9)...
Method A Tetrabutylammonium perchlorate (8.5 g, 25 mmol) was added to a solution containing DMF (49.5 mL) and hydrazine hydrate (0.5 tnL). To this solution was added green Pc2Lu (50 mg, 4.1 x 10 2 mmol). This mixture was stirred for 4 h. The blue-green of the starting solution rapidly became dark blue. Filtration and rapid evaporation under vacuum yielded 7 as a microcrystalline powder. [Pg.824]

The relative apparent molar enthalpy, 4>L, is usually obtained from enthalpy of dilution measurements in which the moles of solute are held constant and additional solvent is added to dilute the starting solution. The process can be represented as... [Pg.358]

As indicated by the final equation, the dilution steps are continued until the infinitely dilute solution is approached. The sum of all of the steps represents the change to infinite dilution from the given starting solution. Thus, the sum of all... [Pg.358]

Figure 7.9(b) shows a graph of values of qL obtained from the series of dilutions of the starting solution as calculated from equation (7.81). Also shown in Figure 7.9(b) are values for L and Lj. These relative partial molar enthalpies can be obtained from 4>L. To find the relationship, we start with the equation... [Pg.360]

Precipitation reactions have many applications. One is to make compounds. The strategy is to choose starting solutions that form a precipitate of the desired insoluble compound when they are mixed. Then we can separate the insoluble compound from the reaction mixture by filtration. Another application is in chemical analysis. In qualitative analysis—the determination of the substances present in a sample—the formation of a precipitate is used to confirm the identity of certain ions. In quantitative analysis, the aim is to determine the amount of each substance or element present. In particular, in gravimetric analysis, the amount of substance present is determined by measurements of mass. In this application, an insoluble compound is precipitated, the precipitate is filtered off and weighed, and from its mass the amount of a substance in one of the original solutions is calculated (Fig. 1.6). Gravimetric analysis can be used in environmental monitoring to find out how much of a heavy metal ion, such as lead or mercury, is in a sample of water. [Pg.93]

Table 1.1 summarizes the solubility patterns of common ionic compounds in water. Notice that all nitrates and all common compounds of the Group 1 metals are soluble so they make useful starting solutions for precipitation reactions. Any spectator ions can be used, provided that they remain in solution and do not otherwise react. For example, Table 1.1 shows that mercury(I) iodide, Hg2I2, is insoluble. It is formed as a precipitate when solutions containing Hg22+ ions and I ions are mixed ... [Pg.93]

Begin by identifying the major species in the two starting solutions ... [Pg.1276]

It was shown (1-3) that the silicon alkoxide solutions become spinnable when an acid is used as catalyst and the water content of the starting solution is small at less than 4 or 5 in the water to silicon alkoxide molar ratio. Recently, it has been found that this rule for the possibility of drawing fibers is only valid for the solutions reacted in the open system and no spinnability is found in the solutions reacted in the closed system (4). It has also been found that the addition of very large amounts of acid to the starting solution produces relatively large round-shaped particles, preventing the occurrence of spinnability (4). These will be discussed in the first half of this paper. [Pg.345]

So far the results have been shown in which the metal alkoxide solutions are reacted in the open system. It has been shown that the metal alkoxide solutions reacted in the closed container never show the spinnability even when the starting solutions are characterized by the low acid content and low water content (4). It has been also shown from the measurements of viscosity behavior that the solution remains Newtonian in the open system, while the solution exhibits structural viscosity (shear-thinning) in the closed system. [Pg.348]

Whether the adsorption of molecules at the surface of minerals is a curse or a blessing for the adsorbed substances depends on many parameters. Experiments showed very different adsorption behaviour of adenine on different minerals. Active minerals are of particular importance for hydrothermal processes (see Sect. 7.2). The surface concentration of adenine on pyrites is fifteen times, that on quartz five times, and on pyrrhotite three and a half times as high as in a starting solution whose concentration is 20 pM (Cohn, 2002). [Pg.95]

Figure 5.18. Relationship between white phosphorus concentration of the starting solutions and electrical resistivity of resulting doped-Si films. [Reproduced with permission from Ref. 25. Copyright 2007 The Japan Society of Applied Physics.]... Figure 5.18. Relationship between white phosphorus concentration of the starting solutions and electrical resistivity of resulting doped-Si films. [Reproduced with permission from Ref. 25. Copyright 2007 The Japan Society of Applied Physics.]...
In many cases a start solution (as shown in Figure 4.3) already exists or is easy to obtain. The most common target is the due date where we distinguish between the... [Pg.66]

Fig. 4.12 The difference before and after the change of the network. The first scheduling result shows a start solution before the change of the network, the second after the change. The planning horizon necessary to take all processes is reduced from about 20 years to 2.5 years. Fig. 4.12 The difference before and after the change of the network. The first scheduling result shows a start solution before the change of the network, the second after the change. The planning horizon necessary to take all processes is reduced from about 20 years to 2.5 years.
The starting solution contained 1.0 mol/liter of ethylene oxide, 55 mol/liter of water and 0.9 wt% of acid. Neglect any changes in water concentration and find the pseudo first order specific rate. [Pg.137]

Generate starting solution P, and set Best solution = P Evaluate obj(P)... [Pg.396]

First, the effect of SL is immediately apparent. Low SLs can be employed in the laboratory to minimize pH shifts. At high SLs, oxides exhibit a dramatic effect on pH. In fact, this plot predicts that the final pH of DIs is almost always at the PZC of the oxide, unless the starting solutions are extremely acidic or basic [11]. Alternatively, in DI the hydroxyl groups on the oxide surface far outnumber the protons or hydroxide ions initially in solution, and the surface never becomes significantly charged. [Pg.171]

The different molecular species present in a palladium nitrate solution can be easily identified by UV-visible spectroscopy (Fig. 13.2). Two absorption peaks are generally observed at A, = 285 nm and A = 378 nm, the latter being ascribed to free nitrate ions corresponding to the electronic transition from the a to the it state in the NOs ions, as observed in the case of an aqueous solution of NaNOs. The other absorption band at A = 285 nm is assigned to a d-d transition in the aquo complex Pd(H20)4 These UV-visible results show the noncomplexant behavior of nitrate ions toward palladium metallic centers. The palladium containing species in the starting solution is then the planar tetra-aquo complex Pd(H20)4 +. [Pg.258]

After the autoclaving (100°) of D-glucose solutions, both 5-(hydroxy-methyl)-2-furoic acid and 2,5-furandicarboxylic acid were detected. No attempt was made to remove oxygen from the starting solutions. Although the D-glucose solution was not initially acidic, subsequent experience indicated that the final pH was probably 4. Air exposure (mild oxidation) of the mixtures increased the two furancarboxylic acids at the expense of 11. [Pg.288]

The physical properties of crystals depend on admixtures this is common knowledge. The admixtures can be present in a starting solution. Solvent molecules included in a crystal during its formation should be considered a contamination. In this sense, the highest attention should be... [Pg.416]

When Gl, G2 and G3 are separated preparatively at low resolution HPLC, the fractions then concentrated to approximately the original concentration and finally heat-sterilized (120°C, 30 min) each fraction reassumes a ratio of Gl, G2 and G3 as was present in the starting solution. [Pg.127]

Another work on the Hquid phase hydrogenation of acetophenone is that of Casagrande et al. The reaction was studied over a series of silica-supported bimetallic catalysts with various Ru/Cr atomic ratios, which were prepared by reduction at room temperature with aqueous sodium tetrahydroborate. The nanostructured catalysts are very active in the low-pressure hydrogenation of acetophenone, although the selectivity towards 1-phenylethanol did not surpass 22% at 90% conversion. The addition of chromium salts to the starting solution gave rise to... [Pg.267]

The recommended treatment regimen is 20 mg/mL as the starting solution in the drug reservoir of the Small Particle Aerosol Generator (SPAG-2) unit. Treatment is carried out for 12 to 18 hours/day for 3 to 7 days. [Pg.1776]


See other pages where Starting solutions is mentioned: [Pg.28]    [Pg.19]    [Pg.358]    [Pg.359]    [Pg.325]    [Pg.982]    [Pg.125]    [Pg.406]    [Pg.370]    [Pg.774]    [Pg.1276]    [Pg.185]    [Pg.57]    [Pg.177]    [Pg.574]    [Pg.346]    [Pg.158]    [Pg.198]    [Pg.59]    [Pg.298]    [Pg.67]    [Pg.396]    [Pg.397]    [Pg.576]    [Pg.310]    [Pg.342]    [Pg.257]   


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