More Convenient Methods

Before suggesting an approach for predicting the minimum number of shells for an entire network, a more convenient method for determining the number of shells in a single unit must first be found. Adopting the design criterion given by Eq. (7.13) as the basis, then any need for trial and error can be eliminated, since an explicit... 

The experiment we have just described is not very satisfactory from a practical point of view, since it is very difficult to deposit a thin layer of solution between two bulk portions of solvent without some mixing. An experimentally more convenient method consists of layering equal volumes of solvent and solution so that a sharp boundary exists between them at x = 0, with c = Cq for... 

The NaAlCl formed in this process needs to be removed by washing with water, in order to achieve the desired improved stabiUty. A more convenient method for replacing framework-Al with Si is the reaction with ammonium hexafluorosiUcate (35). 

The synthesis of deoxybenzoin from phenacetyl chloride and benzene by the Friedel-Crafts reaction has been described. For symmetrically substituted deoxybenzoins, direct reduction of the readily accessible benzoin is a more convenient method. Reduction of benzoin by zinc dust and acetic acid, and by hydrochloric acid and granulated tin or amalgamated powdered tin has been reported. The present method is based on a publication of the authors. ... 

A more convenient method uses the oxidation of Sg, dissolved in CH2CI2 or CS2, by trifluoroperoxoacetic acid at temperatures between -10 and 0 °C (molar ratio 1 1.5) ... 

This process, sometimes known as sequence tagging, may be a more convenient method of obtaining sequence information but it has to be said that it is unlikely to allow as many residues to be determined as when using the classical Edman approach. 

Pipe runs are normally made up from lengths of pipe, incorporating standard fittings for joints, bends and tees. Joints are usually welded but small sizes may be screwed. Flanged joints are used where this is a more convenient method of assembly, or if the joint will have to be frequently broken for maintenance. Flanged joints are normally used for the final connection to the process equipment, valves and ancillary equipment. 

One of the more convenient methods of adding a twocarbon side chain to the electron-rich 3-position... 

Both interpolation and smoothing of experimental data are of particular importance in all branches of spectroscopy. One approach to this problem was considered in Section 13.3. However, with the development of the FFT another, often more convenient, method has become feasible. The basic argument is illustrated in Fig. S. Given a particular problem whose solution may appear to be difficult, it is sometimes possible to resolve it via recourse to the Fourier transform. 

An alternative and more convenient method was accomplished from 8-methoxyberberinephenolbetaine (131) via the ketol 171a (Scheme 99). Treatment of 171a with 10% aqueous sodium hydroxide furnished the expected... 

A more convenient method for the preparation of this ring system started with thiosemicarbazone 123, whose alkaline cyclization to 2-thio-5-(o-nitrobenzyl)-6-azauracil 125 proceeds smoothly (84CCC2628). In contrast to the above method, it is not necessary to isolate the Z-form of thiosemi-... 

For a more convenient method of preparing sodium ethoxide, see Note 1, p. 18. 

There are several methods for generating low-valent zirconocene species in situ. Although the conventional method has been the reduction of Cp2ZrCl2 with Na/Hg or Mg/Hg, more convenient methods have since been developed for the preparation of symmetrical zirconacyclopentadienes such as Cp2ZrBu2 2 [the so-called Negishi reagent (Eq. 2.2)] [12]. 

In Example 10.2, the range of pressure in the supply tank is specified and a more convenient method of calculation is to split the pressure range into a number of increments. After calculating the mass flow rate, the mass remaining in the tank is determined from the pressure at the end of the increment and hence the required time may be determined. A small refinement is to base the flow rate calculation on the mean pressure in the increment rather than on that at the beginning. 

The net movement upwards of a concentration wave is greater in the direct mode. Fewer cycles are needed to achieve a given separation. Nevertheless, the recuperative mode is probably the more convenient method to use on a commercial scale. Indeed,... 

A more convenient method due to the mild experimental conditions and high yields involves the reaction of diaryl ditellurides with diazomethane. ... 

A more convenient method uses the thermal decomposition of di-iododisulfane which can be generated in solution from commercial chemicals... 

A more convenient method may be used, in which a fluid is pumped and the drops are collected and weighed. Since in some systems (solutions) there may be kinetic effects, care must be taken to keep the flow as slow as possible. This system is very useful in studying what one finds in daily life phenomena oil flow, blood cells flowing through arteries, etc. In those cases where the volume of fluid available is limited, this method may be used with advantage. By decreasing the diameter of the tubing, one can work with fluids less than 1 mL. This may be the case for systems such as eye fluids, etc. 

A much more convenient method of obtaining totally reducing conditions is to convert all the primary radicals to the same secondary reducing radical by adding the appropriate organic solute to N20-saturated water. A prime example of this is the generation of CO2 through reactions (66) and (71) ... 

Conversion of an amide a thioamide enhances the reactivity of that function since it favors the enol form and provides a better leaving group for addition-elimination reactions (mercaptide vs. hydroxide). Thioamides obtained by treatment of diazepi-none such as (15-1) or (16-1) with phosphorus pentasulhde provide starting materials for further modihcation of the benzodiazepine nucleus. (More recently developed reagents such as Lawesson s Reagent or hw(tricyclohexyltin) sulhde provide more convenient methods for that transformation.) Thus, reaction of the thioamide (15-2) with (9-allylhydroxylamine leads directly to the amidine, probably via an addition-elimination sequence of the thioenol tautomer of (15-2). There is thus obtained the antianxiety agent uldazapam (15-3) [17]. 

A more convenient method of preparation is described by Briggs, according to which, the eobaltous carbonate is dissolved in the smallest possible quantity of nitric acid, the solution poured into aqueous ammonia containing ammonium carbonate, and air drawn through the liquid for some time. It is then heated on a water-bath with frequent additions of ammonium carbonate, when the colour of the liquid changes to deep red, and allowed to stand till crystallisation is complete. The water of hydration is not removed on heating to 100° C., nor in vacuo over sulphuric acid at ordinary temperature.3... 

The preparation of triarylmethyl azides via the hydrazine derivative and nitrous acid has been reported [52-54]. A more convenient method is via the carbinol and sodium azide [55]. 

T. Urbanski [70] reported a more convenient method of tritetryl preparation, starting from symmetrical trichlorotrinitrobenzene ... 

A more convenient method of preparation 1 is to pass chlorine into a mixture of sulphur monochloride with a bimolecular proportion of chlorosulphonic acid at —15° C., until solidification occurs. Probably sulphur tetrachloride is first formed and then reacts with the chloro-sulphonie acid ... 

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