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can further include a second buffer, a block co-polymer and a reactive oxygen species, depending upon the final configura› tion of the system. 

[0142] FIG. 2 shows the method of the invention. The sol› vent, the activator and the reactive oxygen species are mixed. The solution is applied immediately to a toxant by physical associate. If desired, the level of remaining toxant can be determined, and if the toxant is not sufficiently decontami› nated (i.e., greater than about 99.4% is removed or neutral› ized), the steps can be repeated. The activator can comprise more than one activator, and can be liquid or dry, or a com› bination thereof. 

[0143] One method of activating the decontaminant formu› lations of the present invention is to generate the peroxy› oxidants using peroxides as activators which generate per› oxycarboxylic acids from their dry or dissolved sources. Such a system can be based on the use of tetraacetyl ethylenedi› amine (TAED) or tetraacetylmethylenediamine (TAMD) as the peroxyacetic acid source. The activator in such a system can be based upon the use of dry hydrogen peroxide sources, such as urea peroxide, sodium perborate, or sodium percar› bonate, which can serve as a buffering agent in an appropriate buffer system to create the quasi-steady state equilibrium of the present invention. Activators provide buffering action for the system. The buffering action of the activators can also be due to carbonate compounds. The function of a buffering agent is generally to drive an acidic or basic solution to a certain pH and then, through the buffering capacity of the solution, prevent a change in the pH. FIG. 3 shows the rate of perhydrolysis of TAED by H$_{2}$ 0 2 in unbuffered water as a function of pH. In the present invention, the organic/aqueous solutions, the reactive oxygen species and their sources, and the activators are part of a carefully balanced buffer solution which establishes a quasi-steady state equilibrium between the generation of peroxy acids and the buffering acid and its conjugate base. 

[0144] In one aspect of the present invention, the buffer capacity of a decontaminant formulation is established by the concentrations of an acid and its conjugate base to create a buffer solution which will resist a change in pH as the per› oxycarboxylic acids are generated from their sources. One skilled in the art would know that the buffering capacity of the decontaminant system should be selected from those buffer solutions which have the midpoint of their titration curves at the optimum of the percarboxylic acid activation curve. One novel discovery that made the present invention possible was the discovery that the isomers of some solvents materially affect the buffering capacity of some buffer systems. The isomers include isomers ofbutanediol and linear or branched› chain alcohols, including but not limited to, linear or branched alcohols with from 1 to at least 15 carbon atoms. Use of these isomers is discussed further below. 

[0145] In one preferred form of the present invention, sodium carbonate is used to generate a bicarbonate buffer system in select organic/aqueous solutions comprising cer› tain solvents from Groups II and IV (See Table 2), where the rate at which hydrogen peroxide is released from one or more peroxide sources is used to modulate the perhydrolysis of peroxyacetic acid from TAED, thereby creating the quasi› steady state equilibrium of the decontaminants of the present invention. 

[0146] Of particular importance to the present invention is that hydrogen bonds account for the unusual properties of water, such as its high boiling point, its large solvency for 

ionic and polar solutes, and its low vapor pressure. In addi› tion, the asymmetry of the water molecule leads to a dipole moment in the symmetry plane pointed toward the more positive hydrogen atoms, enabling each water molecule to enter into multiple hydrogen bonds at any given moment. The exact number of hydrogen bonds in which a molecule in liquid water participates fluctuates with time and depends on the temperature. From molecular modeling ofliquid water at 25° C., it has been estimated that each water molecule par› ticipates in an average of 3.59 hydrogen bonds. At 100° C., this number decreases to 3 .24 due to the increased molecular motion and decreased density, while at 0° C., the average number of hydrogen bonds increases to 3.69. In order for a compound such as an organic solvent or a chemical agent to dissolve significantly in water, it must disrupt the hydrogen bonds between water molecules. This is formally character› ized by Pauling’s second rule, which is discussed below. 

[0147] For the purpose of the present invention, the term "hydrogen bond" can be illustrated by single water molecule (H$_{2}$ 0) in a V-shape, but because the oxygen atom is more electronegative than the hydrogen atoms, the electrons in the molecule tend to gather toward the oxygen end, creating a slightly negative pole with a corresponding slightly positive pole at each hydrogen. This asymmetry of the water molecule leads to a dipole moment in the symmetry plane pointed toward the more positive hydrogen atoms. The measured magnitude of this dipole moment can be calculated: 

<img src='content_image/926214.jpg'>

[0148] This polarity creates a dipole-dipole bond, or hydro› gen bond, between water molecules. More generally, a hydro› gen bond is a type of"dipole-dipole bond." The term "dipole› dipole bond" relates to any solvent which has a large dipole moment, such as the strong dipole of a water molecule, which can enter into dipole-dipole bonds with such polar aprotic solvents as nitriles. Acetonitrile, for example, has a very strong dipole moment that can readily enter into dipole-di› pole bonds with water molecules. Hence, despite being a Group I polar aprotic solvent, acetonitrile is soluble in water in all proportions. 

[0149] The invention relates to certain subsets of the pos› sible organic/aqueous solutions comprising at least one polar amphipathic solvent which can form dipole-dipole bonds, including hydrogen bonds with water. In chemistry, a polar› protic solvent is a solvent that has a hydrogen atom bound to an oxygen as in a hydroxyl group or a nitrogen as in an amine group, or, more generally, any molecular solvent which can donate an H+ or proton. Common characteristics of polar, protic solvents include: 

[0150] solvents display hydrogen bonding 

[0151] solvents have an acidic hydrogen (although they may be very weak acids) 

[0152] solvents are able to stabilize and dissolve ions: 

[0153] cations by unshared free electron pairs 

[0154] anions by hydrogen bonding 

[0155] Examples of polar, protic solvents are water, metha› nol, ethanol, formic acid, butanediol and percarboxylic acids. A polar aprotic solvent shares ion-dissolving power with protic solvents, but lacks an acidic hydrogen. These solvents generally have high dielectric constants and high polarity. Examples of polar, aprotic solvents are acetonitrile, dimeth› ylformamide, methylene chloride, dimethyl sulfoxide, and dioxane. 

