Compound interest, definition

Composite account depreciation, 290 Compound interest, definition of 217-218 (See also specific designation)... 

Derivatives of Biphenyl. By coupling diazo compounds and N-nitrosoacetyl derivatives obtained from substituted anilines with benzene, a large variety of biphenyl derivatives can be prepared in which only one of the rings is substituted. In this manner, the isomeric monosubstituted biphenyls, RCel CeHs, have been prepared in which R = Br, Cl, CH3, OCH3, NO2, CN, etc. The meta derivatives, such as 3-brQmobiphenyl (I), 3-nitrobiphenyl (II), and 3-cyanobiphenyl (III), are of particular interest because they cannot be prepared readily from biphenyl. The usefulness of the methods for the preparation of compounds of definite... 

Compound interest factors definition of 223n., 236-237 tables of 219, 234-235, 240-246 (See also specific name)... 

In an economic evaluation of a project, it is often necessary to evaluate the present value of funds that will be received at some definite time in the future. The present value (PV) of a future amount can be considered as the present principal at a given rate and compounded to give the actual amount received at a future date. The relationship between the indicated future amount and the present value is determined by a discount factor. Discounting evaluates each year s flow on an equal basis. It does this by means of the discount, or present value factor, and the reciprocal of the compound interest factor (1 -(- i)" with... 

The iron(III) compound Fe(acac)2Cl shows temperature-dependent spin-relaxation properties similar to those already found in iron(III) chloro-haemin, and the compound probably has the same square pyramidal structure [132]. The I i> Kramers doublet lies lowest, and at low temperatures results in a fast relaxation and a narrow spectrum. Increasing temperature causes population of the f> level, a slowing of the spin relaxation, and considerable line broadening. The compound is definitely in an 5 = f spin state (ji = 5-98 BM at 301 K) and makes an interesting contrast with the square pyramidal -S = compounds such as (R2NCS2)2FeX discussed in Chapter 8. 

Having settled on a definition of chemoinformatics, it is time for us to reflect on the distinction between chemoinformatics and bioinformatics. The objects of interest of bioinformatics are mainly genes and proteins. But genes, DNA and RNA, and proteins are chemical compounds They are objects of high interest in chemistry, Chemists have made substantial contributions to the elucidation of the structure and function of nucleic adds and proteins. The message is dear there is no clearcut distinction between bioinfonnatics and chemoinformatics I... 

Current chemical information systems offer three principal types of search facility. Structure search involves the search of a file of compounds for the presence or absence of a specified query compound, for example, to retrieve physicochemical data associated with a particular substance. Substructure search involves the search of a file of compounds for all molecules containing some specified query substructure of interest. Finally, similarity search involves the search of a file of compounds for those molecules that are most similar to an input query molecule, using some quantitative definition of structural similarity. 

In this chapter, the definitions used by Perrin in his book on pA a prediction (which also includes a very convenient compilation of o values) will be used. One must be alert to the importance of the number of hydrogens directly attached to the carbonyl carbon several groups have pointed out that aldehydes and ketones give separate but parallel lines, with formaldehyde displaced by the same amount again. What this means is that given one equilibrium constant for an aldehyde (or ketone) one may estimate the equilibrium constant for other aldehydes (or ketones) from this value and p for the addition using a value from experiment, if available, or estimated if necessary. This assumes that there is no large difference in steric effects between the reference compound and the unknown of interest. 

Thiosemicarbazone (RNH-CS-NH-N=CR/R//, tsc) complexes of cobalt(III) have been extensively studied since the early 1980s and continue to attract attention, gaining particularly from an interest in their biological activity and potential cytotoxicity. A truly extensive range of tsc compounds has now been reported, although structural definition of their complexes widely relied on basic analytical and spectroscopic techniques up to the late 1980s, when X-ray crystal structural studies of tsc compounds became more common. A review of thiosemicarbazone and S-alkyldithiocarbazate complexes has appeared.1053... 

The reaction of carbonyl compounds to olefins often yields products difficult to obtain synthetically by other routes. The excellent yields obtainable under proper conditions make this reaction of definite preparative interest. Examples of some synthetic applications of oxetane formation follow ... 

In the course of the tempestuous development of organophosphorus chemistry, interest has only recently been focused on compounds of formally quinquevalent phosphorus having coordination number 3, such as 1, 2, or 3, although one of the other species of this kind has long been postulated as reactive intermediate of solvolysis of phosphorylation reactions. Definite evidence of even proof of the existence of such coordinatively unsaturated phosphorus compounds, however, has been obtained only recently in mechanistic studies, by trapping reactions with suitable cycloaddends, or actually by direct isolation. 

There is no rigid definition of what constitutes a suitable synthesis. The major criterion by which syntheses are judged is the potential value to the scientific community. An ideal synthesis is one which presents a new or revised experimental procedure applicable to a variety of related compounds, at least one of which is critically important in current research. However, syntheses of individual compounds that are of interest or importance are also acceptable. 

The report of the first zinc compound with a Zn-Zn core elicited a number of critical comments on the structure and bonding of decamethyldizincocene, and the interpretation of the results.236,237 None of the authors of these commentaries questioned the data or their interpretation. Parkin, however, has pointed out that the formal oxidation state of +1 for zinc in this compound is merely due to the convention that metals are assigned an oxidation state of 0 when they form bonds with like atoms.237 If the conventional definition of valence, namely the capacity of atoms to form bonds to other atoms is used, then the zinc atoms in decamethyldizincocene are not monovalent, but divalent. The synthesis of a paramagnetic organozinc compound in which zinc uses only one of its two 4s electrons will remain an interesting challenge to many synthetic organometallic chemists. 

---