Double-working

Three-electrode control systems are widely available in the market and there are also four-electrode systems for double working electrodes. The construction is either integral or modular. It is perfectly possible to construct the necessary electronics in-house and, in this case, modular construction is suggested as being more flexible. Operational amplifiers and other components of high quality should be used, particularly for kinetic applications. The elements of a bipotentiostat (independent control of two working electrodes) and a galvanostat are described in ref. 139. 

Regulation of growth by double-working with an interstock... 

Fig. 4.16. Double-working with Summer Red for growth regulation.

The participative planning method is used to reduce the number of interfaces that arise when a complex planning task is solved—that is, one that involves many planning partners and their individual knowhow. It also improves information flow at the interfaces, allows planning processes to be carried out simultaneously, and prevents double work in the form of repeated data input and data transfer. Participative planning is based on the theory that cooperation considerably increases efficiency in finding solutions for complex problems. 

The right concept requires the surveyor to cultivate an interdisciplinary vision of how his work can be of use for more than just the purpose he is contracted for. It is possible that a Third World State Survey Office shaU accept as part of its official control a neatly documented and benchmarked traverse measured by a foreign private survey company. After some decades of collecting such contributions and of properly maintaining them, many a country could dispose of a dense reference network and thereby avoid much double work. 

Faraday does not comment on the fact that when acid and alkali are formed as primary products in the electrolysis of a solution of a salt (e.g. sulphate of soda), at the same time hydrogen and oxygen are evolved as primary products from the water, so that the same current seems to be doing double work on the basis of his law. He made no quantitative experiments in this field (see Daniell, p. 128). Faraday s view precluded the use of metal salt solutions in determining, e.g., the equivalent of copper by electrolysing copper sulphate... 

In the electrolysis of many salt solutions hydrogen and oxygen are liberated at the same time as equivalents of acids and bases, and from the point of view of Faraday s laws the current seems to be doing double work. This was explained by Daniell on the basis of Davy s theory of acids (see p. 275) and Berzelius s of ammonium (see p. 150). Daniell uses equivalents, formulating hydrochloric acid HC and sulphuric acid (S + 4O) + H. He distinguished the chemical and electrochemical formulae of salts ... 

Weighing room (chemical balances) g Double work table... 

The symptoms described by Taylor as existing between departments, such as double work and processes designed as safeguarding measures for the departments. 

But it is clear that single radiogram digitization is not sufficient to detect very thin defects. That is why EDF is working on digital double loading , that means ... 

Figure Bl.28.8. Equivalent circuit for a tliree-electrode electrochemical cell. WE, CE and RE represent the working, counter and reference electrodes is the solution resistance, the uncompensated resistance, R the charge-transfer resistance, R the resistance of the reference electrode, the double-layer capacitance and the parasitic loss to tire ground.

Alternatively, place the mixture of alcohol and red phosphorus in a 500 ml. three-necked flask fitted with a mechanical stirrer, dropping funnel and double surface condenser. Heat the phosphorus - alcohol mixture to about 250°, and add the bromine whilst stirring vigorously. Work up the reaction product as above. 

That looks simple and direct don t it If safrole was used as the alkene one would get safrole-azide as product. Just one teensy little reduction away from MDA. Strike also found some azide papers that, with a little work, will get safrole-azide in a totally different way. Strike came across a lot of work where groups were using dinucleophilic addition to get an azide and a halogen added across a double bond. The azide would always go to the beta secondary carbon and the halogen to the primary carbon (just what one would want if safrole was the substrate). 

If a Michael reaction uses an unsymmetrical ketone with two CH-groups of similar acidity, the enol or enolate is first prepared in pure form (p. llff.). To avoid equilibration one has to work at low temperatures. The reaction may then become slow, and it is advisable to further activate the carbon-carbon double bond. This may be achieved by the introduction of an extra electron-withdrawing silyl substituent at C-2 of an a -synthon. Treatment of the Michael adduct with base removes the silicon, and may lead as well to an aldol addition (G. Stork, 1973, 1974 B R.K. Boeckman, Jr., 1974). 

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