Short Contents

Appendix B Short Contents of Comprehensive Heterocyclic Chemistry - H 695... 

In this endeavor the original author of Handbook-I has been joined by Alexander Pozharskii of the University of Rostov, Russia. We have adopted for Handbook-II (for the most part) the arrangement and classification of Handbook-I. However, a large amount of new material has been added, most of which has been taken from the 10 volumes of CHEC-II. In many instances we have utilized pieces of actual text and structural schemes directly from CHEC-II. Because of the close relationship to CHEC and to CHEC-II, the Foreword, Introduction to CHEC-II and Short Contents of both CHEC and CHEC-II are reprinted as part of the Part I Preliminaries of Handbook-II. Just as for Handbook-I, the organization of Handbook-II follows that of the CHEC and CHEC-II rather closely except in the case of ring synthesis, and Chapter 1.3 of the Handbook describes these divergencies. 

The basic requirements for the Mephisto model was satisfactory accuracy, that means prediction of amplitude, position and phase relation between the various signals, and short computation times, typically a few minutes for the simulation of a whole Cscan, compatible with an intensive use. These a priori contradictory characteristics have been contented by means of appropriate approximations based on physical considerations. 

The results showed that some yards used ultrasonics to examine thousands of checkpoints for quality control purposes whilst others were content to examine the almost the minimum number that would be accepted. It is cleeu from the results that the minimum extent of NDE recommended by Classification Societies falls some way short of that applied for quality control purposes by some shipbuilders. 

A separator is fed with a condensate/gas mixture. The condensate leaves the bottom of the separator, passes a flowmeter and is followed by a choke valve, after which the condensate is boiling. The flow can not be measured using the transit time method, due to the combination of short piping, the absence of a suitable injection point and the flow properties of the condensate, which is non-newtonian due to a high contents of wax particles The condensate can not be representatively sampled, as it boils upon depressuratioh... 

The first part of the method involves sorting all the atoms into their appropriate cells. This sorting is rapid, and may be perfonned at every step. Then, within the force routine, pointers are used to scan tlirough the contents of cells, and calculate pair forces. This approach is very efficient for large systems with short-range forces. A certain amount of unnecessary work is done because the search region is cubic, not (as for the Verlet list) spherical. 

Now roll up the Carius tube (while still in a vertical position) in a strip of ordinary thick drying paper, and then place it in the heavy iron protector tube if the Carius tube is too short and tends to disappear within the iron tube, a short section of old glass tubing should first be placed in the iron tube so that the capillary of the Carius tube just projects. The function of the paper is to protect the Carius tubing from being scratched, and also (more important) to prevent the local overheating which would otherwise occur at places where the Carius tube is in direct contact with the iron tube. The sealed tube, throughout its manipulation, should be left as nearly vertical as possible, so that the contents do not leave the rounded end. 

Mix 50 ml. of formalin, containing about 37 per cent, of formaldehyde, with 40 ml. of concentrated ammonia solution (sp. gr. 0- 88) in a 200 ml. round-bottomed flask. Insert a two-holed cork or rubber stopper carrying a capillary tube drawn out at the lower end (as for vacuum distillation) and reaching almost to the bottom of the flask, and also a short outlet tube connected through a filter flask to a water pump. Evaporate the contents of the flask as far as possible on a water bath under reduced pressure. Add a further 40 ml. of concentrated ammonia solution and repeat the evaporation. Attach a reflux condenser to the flask, add sufficient absolute ethyl alcohol (about 100 ml.) in small portions to dissolve most of the residue, heat under reflux for a few minutes and filter the hot alcoholic extract, preferably through a hot water fuimel (all flames in the vicinity must be extinguished). When cold, filter the hexamine, wash it with a little absolute alcohol, and dry in the air. The yield is 10 g. Treat the filtrate with an equal volume of dry ether and cool in ice. A fiulher 2 g. of hexamine is obtained. 

Neutralise the cold contents of the flask with 500-600 ml. of 40 per cent, aqueous sodium hydroxide solution, equip the flask for steam distillation and steam distil until about 1 litre of distillate is collected. The steam distillate separates into two layers. Add solid sodium hydroxide (< 100 g.) to complete the separation of the two layers as far as possible. Remove the upper (organic) layer and extract the aqueous layer with three 50 ml. portions of chloroform. Dry the combined organic layer and chloroform extracts with anhydrous potassium carbonate and distil the mixture through a short fractionating column (e.g., an 8 Dufton column) after a fore run of chloroform, followed by pyridine, collect the crude 4-ethylpyridine at 150-166° (49 g.). Redistil through a Fenske-... 

Heating under reflux.—A water condenser of total length 25 cm, (cooling jacket 15 cm.) may be used. If the upper end is provided with a long side arm as in Fig. XII, 2, 9, refluxing may be followed by distillation without transferring the contents of the flask it may be necessary to surround part of the side arm with a short water condenser (compare... 

In those cases where stirring for short periods is necessary, this may usually be accomphshed by gentle rotation of the vessel thus imparting a swirhng motion to its contents. If the vessel cannot conveniently be moved, a hand-operated stirrer constructed entirely of glass (compare Fig. II, 10, 4 and Fig. II, 10, 2) will be found satisfactory provided the glass loop is not too large. 

As will be seen shortly, an analogous result is obtained with the silica-water system, where the BET monolayer capacity of water calculated from the water isotherm is roughly equal to the hydroxyl content of the silica surface. 

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