Generic groups

An alternative to retrieval by means of an atom list is a structure search performed by means of a user-defined generic group which contains only chlorine... 

Part of the structure editor screen with dialog windows to specify the attachment 1 user-defined generic groups. 

Many attempts have been made to characterize the stabiUty of the colloidal state of asphalt at ordinary temperature on the basis of chemical analysis in generic groups. For example, a colloidal instabiUty index has been defined as the ratio of the sum of the amounts in asphaltenes and flocculants (saturated oils) to the sum of the amounts in peptizers (resins) and solvents (aromatic oils) (66) ... 

Query 2 an aromatic group and a hydrogen-bond acceptor center. R1 is a complex generic group (not detailed here) which delimits the search to all groups that provides lone-pair electrons to the hydrogen bond. 

The range of heat emitters may be divided into three generic groups ... 

Figure 19.7 The activity spectrum for different generic groups of compounds that bind to the benzodiazepine domain on the GABAa receptor...

This behavioural syndrome, rather emotively called learned helplessness", is widely believed to share many features of depression, not least because both culminate in psychomotor retardation and both are linked with experience of uncontrollable, unpredictable stress. Whether or not learned helplessness really is an analogue of depression remains controversial (Maier 1993). Nevertheless, escape deficits in rats are prevented by pretreatment with antidepressants from different generic groups. Other psychotropic agents, such as CNS stimulants and neuroleptics, are generally ineffective. 

Figure 2. Interconversion coordinate used in generic group exchange reactions. In this case a Sjq2 model is described. The donor and acceptor in the scheme above would correspond for instance to an halide ion Y- entering from the right in the APC and the leaving group is the halide ion Y-. The central carbon is shetched by the dark circle. The distance R is determined by the SPi-1, and the quantum states to the left and the right of the plane formed by the 3-substituents linked to the C-atom being different, they cannot physically be reached by an adiabatic process as implied in the BO-scheme if quantum mechanics must prevail (two different quantum states cannot be linked adiabatically ).

The letter R in the following illustrations is widely used as a symbol for a generic group. It may stand for simple substituents such as H- or CH3-, or for complex groups composed of many atoms of carbon and other elements. 

A protocol is also used to describe a set of guidelines appropriate to a particular analytical area or generic group of operations. Examples include, a protocol to ensure a safe working environment, a protocol for the best way to choose the right method, a protocol for the conduct of collaborative tests, or a protocol for the best way to keep an analytical step or steps free from contamination. 

There are some generic terms (like carbohydrates, proteins, volatile fatty acids, PCBs) that are used to describe a group of compounds or components. The analyst needs to be sure whether it is the total amount of the generic group that is to be measured in a sample or rather some specific compounds that are of importance for the current study. 

In this book, reactions are organized by similar process. Reactants are gathered into generic groups that behave similarly. A reaction mechanism is our current best guess at all the steps for how the reaction actually occurs. Even the most complex reactions can... 

Acid and Base Generic Groups and the Proton Transfer Path Conjugate Bases and Acids Proton Transfer Reactions Favor Neutralization Charge Types... 

Acid and Base Generic Groups and the Proton Transfer Path... 

A much smaller set of sources is responsible for most reactions and is summarized in Table 5.2, which gathers examples, reactivity trends, common reactions, necessary decisions, and the related generic groups. Some have a decision discussed in Chapter 9. 

Symbol Name Common Examples in Order of Decreasing Reactivity Reactivity Trend Principle Common Reactions Decision Related Generic Groups... 

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