SUBJECTS apparatus

Friction can now be probed at the atomic scale by means of atomic force microscopy (AFM) (see Section VIII-2) and the surface forces apparatus (see Section VI-4) these approaches are leading to new interpretations of friction [1,1 a,lb]. The subject of friction and its related aspects are known as tribology, the study of surfaces in relative motion, from the Greek root tribos meaning mbbing. 

According to an elegant remark by Davies [5], "Modem scientific data handling is multitechnique, multisystem, and manufacturer-independent, with results being processed remotely from the measuring apparatus. Indeed, data exchange and storage are steps of the utmost importance in the data acquisition pathway. The simplest way to store data is to define some special format (i.e., collection of rules) of a flat file. Naturally, one cannot overestimate the importance of databases, which are the subject of Chapter 5 in this book. Below we discuss three simple, yet efficient, data formats. 

It has already been pointed out that a liquid even when subjected to simple atmospheric distillation may become superheated and then bump violently in consequence this danger is greatly increased during distillation under reduced pressure and therefore a specially designed flask, known as a Claisen flask, is used to decrease the risk of superheating. In Fig. i2(a) a Claisen flask D is shown, fitted up as part of one of the simplest types of vacuum-distillation apparatus. ... 

It is hoped that the account of the interchangeable ground glass joint apparatus already given will serve as an introduction to the subject. For the numerous apphcations of such apparatus, the reader is referred... 

This subject is dealt with ab initio in the author s book entitled Elementary Practical Organic Chemiairy. Parti. SmaU Scale Preparations. (Longmans, Green and Co. Ltd., 1957.) The treatment is comprehensive and includes a detailed account of small scale apparatus of novel design. 

Thus, unacceptable stresses can arise in rigid construction materials in apparatus, equipment, piping, etc. if subjected to large temperature fluctuations. For example, conventional glass is prone to failure due to thermal shock. 

In an experiment in which a sample is subjected to controlled shock loading and preserved for post-shock analysis, the shock-recovery experiment, the quantification, and the credibility of the experiment rest directly upon the apparatus in which the experiments are carried out. Quantification must be established with two-dimensional numerical simulation and this can only be accomplished if the recovery fixtures are standardized. The standardized fixtures must be capable of precise assembly so that the conditions actually achieved in the experiment are those of the simulation. 

The production of tetracycline by catalytic dechlorination is described in U.S. Patent 2,699,054 as follows Pure chlortetracycline (4.8 grams) was suspended in 100 ml of methanol and sufficient anhydrous dioxane was added to completely dissolve the product. To the solution was added 0.5 gram of 5% palladium-on-charcoal catalyst. The mixture was placed in a conventional hydrogenation apparatus and subjected to a pressure of 50 psi of hydrogen while being agitated. 

Hertz s last piece of experimental work was done when his health was deteriorating and he was devoting most of his research time to intensive theoretical work on the logical foundations of mechanics. In 1892 in his laboratoi-y in Bonn, he discovered that cathode rays could pass through thin metallic foils. He published a short paper on the subject, but did not pursue the matter further. Instead he handed his apparatus and his ideas over to Philipp Lenard (1862—1947), his assistant in Bonn. Lenard pushed Hertz s suggested research so far that Lenard received the Nobel Prize in Physics in 1905 for his work on cathode rays. ... 

Fig. 19.23 Campbell test apparatus for determining the various forms of attack that condenser-tube materials are subjected to in service (after Campbell...

The common heater block shown in Fig. 19.23 can itself be subject to corrosion leading to different heat transfer conditions for different tubes, and in some later versions of the apparatus individual short heating jackets are used for each tube, which are heated with oil from either a steam-heated or electrically heated heat exchanger. This modification not only avoids corrosion problems but also obviates the necessity to machine a length of the outside of each tube to fit the semi-circular notches in the single heater block. The oil flow is adjusted to give an oil temperature of 95°C at each outlet. 

The physical principles of air-conditioning, its methods of application and the suitable apparatus are the subject of Chapters 23-28. 

In view of the foregoing remarks, it is clear that all glassware used in the preliminary treatment of samples to be subjected to stripping voltammetry, as well as the apparatus to be used in the actual determination, must be scrupulously cleaned. It is usually recommended that glassware be soaked for some hours in pure nitric acid (6 M), or in a 10 per cent solution of pure 70 per cent perchloric acid, followed by washing with de-ionised water. 

Hematoporphyrin dimethyl ester (15, 1.52 g, 2.43 mmol) (diastereomeric mixture) and Af.At-dimethyl-acetamide dimethyl acetal (8 mL) were suspended in o-xylcnc (100 mL), degassed and then heated with exclusion of light in a flask equipped with a reflux condenser and a Soxhlet apparatus containing 3 A molecular sieves. The temperature was raised during 15 min from rt to 115 C and kept at this temperature for 30 min. Then the temperature was raised to 155 C and the mixture kept at this temperature for 3 h. The mixture was evaporated in a bulb tube and the residue subjected to column chromatography [silica gel (ICN), CH2Cl2/MeOAc/MeOH 10 5 0.5] with exclusion of light yield of pure 16A 305 mg (17 %) yield of pure 16B, 375 mg (20%) and 187 mg (10%) of a mixture of 16 A and B. 

The subject index provides access to the text by way of methods, techniques, reaction types, apparatus, effects and other phenomena. Also, it lists compound classes such as organotin compounds or rare-earth hydrides which cannot be expressed by the empirical formulas of the compound index. 

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