Golden excess

The golden excess, calculated for all stable nuclides is shown in Figure 4.9. 

Figure 4.9 Golden excess of protons on atomic nuclei as a function of mass number...

The observation that the convergence of Z/N -> r promotes nuclear stability was interpreted to imply a packing mode for nucleons in three-dimensional analogy of botanical phyllotaxis. The general property, N >Z, of stable nuclides then results in a golden excess of x = Z — xN protons, which form an electrically... 

It is important to note that whereas the BCS theory only applies to special low Tc materials, the golden-excess model covers all superconductors. The disadvantage of currently known HTSS is the brittleness of the ceramic materials that complicates the manufacture of flexible wires made up of well-aligned crystals. Raising the critical temperature, T, of cheap industrially important metals by isotopic enrichment offers a more manageable alternative technology. 

The nature of the relationships and constraints in most design problems is such that the use of analytical methods is not feasible. In these circumstances search methods, that require only that the objective function can be computed from arbitrary values of the independent variables, are used. For single variable problems, where the objective function is unimodal, the simplest approach is to calculate the value of the objective function at uniformly spaced values of the variable until a maximum (or minimum) value is obtained. Though this method is not the most efficient, it will not require excessive computing time for simple problems. Several more efficient search techniques have been developed, such as the method of the golden section see Boas (1963b) and Edgar and Himmelblau (2001). 

Complex 165 reacts with CO at room temperature to give />-tolyl isocyanate and the golden dicarbonyl compound 166. The latter can also be generated by reaction of 164 with excess of CO and converted back to imide 165 by the addition of 2 equiv of /> toly 1 azide (2003JA322). Reaction of cobalt(m) imide 167 analogous to 165, available from [PhB(CH2PPh2)3]CoI 156 by the same procedure as for 165, with CO proceeds similarly <2002JA11238>. 

Chemical reduction of Cu -loaded G4-OH dendrimers (G4-OH/Cu +) with excess NaBH4 results in intradendrimer Cu clusters (Fig. 3). Evidence for this comes from the immediate change in solution color from blue to golden brown the absorbance bands originally present at 605 nm and 300 nm disappear and are replaced with a monotonically increasing spectrum of nearly exponential slope towards shorter wavelengths (Fig. 11). 

The hepatocarcinogenicity of dieldrin in mice has been confirmed in several experiments, and in some cases, the liver cell tumors metastasized. No excess of tumors has been observed in a number of bioassays in rats and one bioassay in Syrian golden hamsters. ... 

The Romans were the first to discover the vicissitudes of a culture a that derives its power from finance. Gold, like any other commodity, I does not have an absolute value it depends on how much of it there is around. The gold denomination of the Roman Empire was the aureus, which was worth twenty-five silver denarii. But the later emperors were prone to grotesque displays of wealth - Nero constracted a Golden House with jewel-encrusted walls. These excesses removed so much gold and silver from circulation that the coin minters were forced to add other metals to the aureus and the denarius. By the third century ad the denarius was 98 per cent copper. Naturally, a trader will not give as much for a coin that is mostly copper as for one that is pure silver, even if they are called the same thing and bear the same stamp. 

Such tendencies may be reduced by growing crystals very slowly, for instance, by extremely slow cooling or evaporation. In fact, when it is desired to obtain perfect crystals for goniometric or X-ray work, the golden rule is to grow them as slowly as possible. Excessive nucleus formation in solutions can often be avoided by removing dust particles in the following way. A solution saturated at, say, 30° C is made up and allowed to cool without disturbance to room temperature it is then suddenly disturbed, so that a shower of small crystals is formed these... 

Addition of excess of potassium thiocyanate to an alkaline solution of a niobate, followed by zinc and concentrated hydrochloric acid, produces a golden-brown colour which may be almost red in the presence of larger quantities of niobium. It is stated that ndther tantalum nor titanium gives any coloration under the same conditions.3 Addition of... 

Degradation in bulk. Davis and Golden (85) have studied the degradation of PTHF in bulk at various temperatures. The polymers that they studied were prepared using a THF/PF5 complex either in an open flask (polymer A) or in vacuum with exposure to air during the work up (polymer V). The intrinsic viscosity of polymer A. heated at fixed temperatures up to 150° C in a sealed system, fell rapidly to a constant value. Polymer V behaved similarly but the decrease was considerably smaller. When heated in air at a fixed temperature the viscosity of both polymers decreased continuously with eventual destruction of the polymer. Temperatures well in excess of 150° C were required for complete degradation of polymer A or V in vacuum. 

To a solution of 6.7 g 2,5-dimethoxy-(i-propylthio)benzaldehyde in 40 g of nitromethane there was added 0.10 g of anhydrous ammonium acetate, and the mixture was heated on the steam bath for 2 h. The excess reagcnt/solvent was removed under vacuum yielding 8.9 g of orange solids. This was recrystallized from 200 mL boiling MeOH providing 6.2 g of 2,5-dimethoxy-B-nitro-4-(i-propyT thio)styrene as lustrous golden orange platelets. 

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