When Rendering

There are a number of powerful synthetic reactions which join two trigonal carbons to form a CC single bond in a stereocontrolled way under proper reaction conditions. Included in this group are the aldol, Michael, Claisen rearrangement, ene and metalloallyl-carbonyl addition reactions. The corresponding transforms are powerfully stereosimplifying, especially when rendered enantioselective as well as diastereoselective by the use of chiral controller groups. Some examples are listed in Chart 20. 

Inexperienced young pigeons, when rendered anosmic before release, have oriented normally in one experiment (Wiltschko and Wiltschko, 1987) but were impaired in another (Gagliardo etal., 1988). In the latter experiment, the birds... 

Heavy Metals. — The solution of 1 gm. of potassium bisulphate in 20 cc. of water should not be affected by hydrogen sulphide water nor by ammonium sulphide solution when rendered slightly alkaline with ammonia water. 

Wet Tests.—(a) When rendered faintly acid, colourless solutions of vanadates become yellow, and, with the addition of more acid, orange-red, in consequence of the formation of polyvanadates. 

Almost simultaneous with the publication of Kossel s paper there appeared a rival electronic theory. The American chemist Lewis introduced the idea of the covalent electron-pair bond. Like Kossel, he was impressed by the apparent stability of the noble gas configuration. He was also impressed by the fact that, apart from many compounds of the transition elements, most compounds when rendered as molecules have even numbers of electrons, suggesting that electrons are usually found in pairs. Lewis devised the familiar representations of molecules and polyatomic ions (Lewis structures, or Lewis diagrams) in which electrons are shown as dots (or as noughts and crosses) to show how atoms can attain noble gas configurations by the sharing of electrons in pairs, as opposed to complete transfer as in Kossel s theory. It was soon apparent from the earliest X-ray studies that Kossel s theory was more appropriate... 

Optometrists have an obUgation to adhere to a reasonable standard of care when rendering services to patients. This standard may be siunmarized by the question, What would a reasonable optometrist do under the same or similar circumstances From this question it is apparent that the defendant optometrist s conduct is to be compared with the conduct expected of a hypothetical reasonable optometrist. If the defendant optometrist s conduct fails to measure up to the conduct expected of this reasonable practitioner, a breach of the standard of care occurs. Proof of negligence, however, entails more than a demonstration that the defendant optometrist has violated the standard of care.There are, in feet, four elements to this tort, and to state a cause of action in a court of law the plaintiff-patient must offer evidence in support of each.These four elements are as follows ... 

In 1801, H. Davy stated that 4 dry caustic potash and soda are conductors of galvanism when rendered fluid by a high degree of heat, but the fact made little impression, for, about ten years later, he said that water is necessary for these substances to conduct electricity, M, Faraday made observations on the electrical conductivity of fused potassium hydroxide. The electrical conductivities of aq. soln. of the alkali hydroxides 45 are indicated in Table XII, where v denotes the... 

The important property of these compounds is that they will couple with aromatic amines and hydroxy derivatives to form highly coloured products which, when rendered soluble by sulphonation, give rise to a great range of dyestuffs known as the azo dyes. A simple example of a coupling reaction is shown in the following equations ... 

An engineer employs lines to depict features of the possible movements of machinery. To an untrained observer, schematic illustrations seem static, providing a still-life vision of a bulky device. But literate viewers can apprehend movement from such diagrams. An attentive observer anticipates how our perceptions would change from the possible movement of objects. When rendered in two dimensions, the lines of an engineer s design plan he between exposed surfaces and hidden ones, from the reader s perspective. 

Reductive conversion of meso-cycYic imides to w-hydroxyalkanamides is enantio-selective when rendered by the hydrogenation catalyst lO/ ... 

These aqueous solutions, when rendered alkaline with ammonia or sodium carbonate (sodium hydroxide when phenolic alkaloids are known to be absent), may yield the basic constituents in filterable form. However, experience has shown that it is more convenient to recover these by extraction with ether or chloroform. Chloroform is to be preferred for it extracts all alkaloids except the quaternary bases (curine), which in any case must be recovered in the form of an insoluble complex salt. This procedure fails when the alkaloids are unstable under the conditions of the experiment, and is conspicuously unsuccessful mth the ergot bases. It is also probable that some alkamine esters suffer change under the conditions imposed. 

Figure 3.3 Demonstration of the good fit between the Slater 2s radial approximation, when rendered orthogonal to the Is function, and the numerical radial function as output of the Herman-Skillman program. The other details of the spreadsheet are as in Figures 3.1 and 3.2.

The data presented in Table 1.1 can be read in another way. To obtain a measurable half-life (say, > 1 s) for a colloidal dispersion of naked, uncharged particles, a number concentration of less than 10 dm would be required. This means that, when rendered unstable, dispersions of practical importance, which usually contain more than 10 particles per dm, will coagulate at an immeasurably fast rate, at least in terms of the measuring techniques developed to date (Parfitt and Peacock, 1978). Of course, some very dilute dispersions can be encountered in water treatment, for example, and their rate of coagulation will be correspondingly slower. 

Faraday used the name voltameter . He speaks of water being decomposed with facility when rendered a better conductor by the addition of acids or salts ( 706). Three forms of voltameter are shown in Fig. 10. He did not use a galvanometer. 

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