Grid networks

The spray aeration method comprises a grid network of piping and nozzles over a pond or basin. Contaminated water is simply sprayed through the nozzles and into the air to form droplets. Mass transfer of the contaminant takes place across the air-water surface of the droplets. Mass transfer efficiency can be increased by multiple passing of the water through the nozzles. This method has three disadvantages ... 

For wind, an intermittent source of power, to be linked into the electricity market, utilities need to develop a strategic grid network — one in which other types of power generation can be switched to low output to compensate for high wind energy output and vice versa. 

The use of isonicotinic acid ligands leads to a threefold interpenetrated neutral square grid network in which [Pt(L)2(HL)2] building blocks (L = isonicotinate) (cf. IX), resulting from deprotonation of half of the acid groups, are linked by carboxyl-carboxylate hydrogen bonds (Figure 18) [27c,57]. A network of the same... 

Figure 1 Square grid network formed by ligand 1 and C0CI2.

The formation of the above noninterpenetrated square grid in the EtOH-F O solvent system was studied using different ratios of 2 and Cd(NO)3 [14]. These results indicate that at a 2 Cd(N03)2 ratio of >2.5, the formation of the square grid network was always favored. Notably in this structure the interlayer separation is much smaller (4.8 A versus 6.3 A) than that of above-described structure owing to the absence of large guest molecules. Interestingly, the hydrophobic... 

Figure 2 Interpenetrated square grid network in the crystal structure of [Zn(2)2(H20)2] [SiF6] .

Figure 3 Inclusion of o-dibromobenzene (space filling mode) in square grid networks of 2 and Cd(N03)2.

A larger square grid network than that of 2 was first reported in the product formed between ligand 3 and Fe(II) NCS [18]. In the network the Fe(II) ions are separated by 3 with a distance of 13.66 A. However, the networks are doubly interpenetrated in diagonal-to-diagonal fashion, similar to that of 2 (Figure 2), with an interplanar separation of 11.3 A between the parallel sheets. The solvent (MeOH) molecules occupy the channels formed between the interpenetrated... 

Figure 5 Interpenetration of pyrene network (space filling mode) through the square grid networks of 2 and Ni(N03)2. The coordination and pyrene networks are represented perpendicular and parallel, respectively, to the plane of the paper.

Figure 8 Square grid network exhibited in the complex of 8 and Cul.

The importance of host-guest interactions in the predictable formation of open square grid networks was further exemplified with the reaction of Ni(N03)2 or Cu(N03)2 and ligand 8 in the presence of benzene [21]. With Ni(N03)2 it formed a doubly interpenetrated network as the anthracene moiety prefers to interact with itself rather than with benzene (Figure 9). With Cu(N03)2 it failed to form a 2D network but formed two types of one-dimensional chains. 

In a similar fashion to the above ligands, the ligand 9 was also shown to form an open square grid network containing the largest square cavities reported so far [24], A noninterpenetrated 2D network containing square grids of dimensions 20 x 20 A was obtained when 9 was treated with Ni(N03)2 in the presence of either benzene... 

Mak and co-workers have shown how the ligands 1 and 2 react with Cu(II) to form a rectangular grid network of dimensions 6.83 x 11.15 A (Figure 11) [29], The Cu atom adopts an elongated octahedral geometry with two moieties of 1 and two... 

The square grid network formed between Cd(N03)2 and 2 was shown to catalyze the cyanosilylation of aldehydes [13]. The treatment of benzaldehyde with cyano-trimethylsliane in a CH2C12 suspension of powdered (Cd(2)2(N03)2 n at 40 °C for 24 h resulted in 2-(trimethylsiloxy)phenylacetonitrile in 77% yield. Further, no reaction was observed with powdered Cd(N03)2 or 2 or the supernatant liquid of a CH2C12 suspension of Cd(2)2(N03)2 alone, and also the shape selectivity was observed in catalysis, 2- and 3-tolualdehyde being cyanosilylated in 40 and 19% yields, respectively. These observations indicate that the reaction was promoted heterogeneously by square grid cavities of Cd(2)2(N03)2 . 

Figure 20 Linking of 11 x 11A square grid network with PF6 anions.

Square grid networks generated with bipy spacer ligands were first reported by Fujita et al.46 Fujita s structures are based on Cd(II) and numerous other examples have subsequently been reported based on a number of other transition metals, including Ni(II) and Co(II). Although these 2D coordination networks are essentially identical within the coordination grid (square dimensions ca. 11.5 x 11.5 A), the crystal structures of compounds differ in the mode that networks stack with each other (interlayer separations range from 6-8 A). 

Area sources include die multitude of minor sources with individually small emissions diat are impractical to consider as separate point or line sources. Area sources are typically treated as a grid network of square areas, widi pollutant emissions distributed uniformly within each grid square. Area source information required includes types and amounts of pollutant emissions, die... 

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