Stock notation

For compounds or ions containing elements that have a variable oxidation number, Roman numerals are used to indicate the oxidation number of the element concerned, and so name the chemical species. This is called Stock notation, after the chemist A. Stock who devised the method. 

Many transition metals and the group of six elements centered around lead on the periodic table commonly have more than one valence. The valence of these metals in a compound must be known before the compound can be named. Modern nomenclature rules indicate the valence of one of these metals with a Roman numeral suffix (Stock notation). Older nomenclature rules used different suffixes to indicate the charge. Examples ... 

The Roman numeral suffix is part of the name of the metal. Thus iron(III) is one word. Stock notation should be used for all metals that have a variable valence. This includes almost all the transition elements and the elements immediately around lead on the periodic table. Stock notation is often omitted for Zn, Cd, and Ag, as they do not have variable valence. The valences of some common metals and acids are listed in Appendix C. 

These are of three types, containing manganese with, respectively, +4, - -5 and +6 charges. These are best indicated by the Stock notation of Roman numerals. 

The concept of oxidation number is used in the modern chemical naming of ionic inorganic substances. This system of nomenclature, or naming, is called the Stock notation. In this system the oxidation number is inserted immediately after the name of an ion. Roman numerals are inserted after the name or symbol of the element. For example ... 

This is because, for example, the names chlorate (Figure 9.10) and manganate are not precise enough and potentially refer to more than one species. For compounds between non-metals the Stock notation is generally not used and the actual numbers of tbe atoms in tbe molecular formula are shown in the name. For example, dinitrogen oxide, N2O, rather than nitrogen(i) oxide and sulfur hexafluoride, SFg, rather than sulfur(vi) fluoride. 

The greater part of inorganic nomenclature was for many years handled with reasonable ease by means of the endings -ic, -ous, -ium, -ide, -ite, and -ate When these did not suffice, help was sought mainly in prefixes of the type pyro-, hypo-, meta-, ortho-, per-, sub-, and in endings such as -oxylic, -yl, -osyl. There was, however, little consistency in the use of these adjuncts, and the resulting confusion was made worse when later studies of structure disclosed irrationalities in place of some of the supposed analogies. The Stock notation helped in many cases, and Werner s nomenclature was invaluable for coordination compounds. 

If the metal ion may exist in more than one oxidation state, this oxidation state should be listed, in Roman numerals, immediately after the name of the metal ion. The Roman numeral is enclosed in parentheses and is considered part of the same word, and not a separate grouping. If the metal occurs in only one oxidation state, no such indicator is used. This notation is the Stock system discussed earlier. 

Metal to metal bonding is indicated by the italicized atomic symbols separated by a long dash and enclosed in parentheses. Bond order may be indicated by an Arabic number above the long dash, e.g. (Mo—Mo). The bond order notation is listed after the central atom names and before the charge or Stock number. For examples see Table 16. 

Since the stock in trade of sophomore year differential equations has often accumulated a few cobwebs by the senior year it is worth pausing to dust them off. The following is a superficial review of a few common types of differential equation and the notation is specific to this section. 

The theoretical aspect of polymer crosslinking developed by Stock-mayer [20] and Flory [21] was extended by Charlesby [2, 22—24] to the irradiation of polymers. Other developments have been given by Shultz et al. [25] and more recently by Saito et al. [26]. The theory of polymer degradation has been developed by many other authors [27—36]. The methods developed by Charlesby will be briefly reported here and his notations will be adopted. Later theories will then be outlined. 

The local chemical stock in tanks is denoted by sus (first sub-layer) whereas the mobile stock in RTCs is denoted by (second sub-layer). The number of loaded and empty RTCs at hand are described by srjj and sr . Table 3.13 summarizes aU notation introduced above (and some more). 

The date used as the point for calculation is the settlement date for the bond, the date on which a bond will change hands after it is traded. For a new issue of bonds the settlement date is the day when the bond stock is delivered to investors and payment is received by the bond issuer. The settlement date for a bond traded in the secondary market is the day that the buyer transfers payment to the seller of the bond and when the seller transfers the bond to the buyer. Different markets will have different settlement conventions for example, UK gilts normally settle one business day after the trade date (the notation used in bond markets is T+ 1) whereas Eurobonds settle on T + 3. The term value date is sometimes used in place of settlement date, however the two terms are not strictly synonymous. A settlement date can only fall on a business date, so that a gilt traded on a Friday will settle on a Monday. However a value date can sometimes fall on a nonbusiness day. 

We consider a supply chain that has a distribution network structure, in which each inventory stocking location has a unique supplier. Each inventory location, also known as a member of the supply chain, is identified by an index m, for which the precise definition depends on the actual network structure. As a building block for analyzing supply chain inventory networks, we shall mainly discuss a simple two-level supply chain consisting of a single retailer (denoted by m = 1 or m = r) and a single supplier (m = 2 or m = s). External demand placed (at the retail point) by the customers of the supply chain during period t is denoted by Dt. Below, we present some of the notation and common assumptions that are relevant to this chapter. 

In this case, as follows from the notation used in Fig. 12(6) gio is the charge of fresh feed stock—fuel oil ... 

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