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Methodology multiplication

For instance, Yadav and Ahuja prepared nanoparticles using gum cordia as the polymer and to evaluate them for ophthalmic delivery of fluconazole. A w/o/w emulsion containing fluconazole and gum cordia in aqueous phase, methylene chloride as the oily phase, and dioctyl sodium sulfosuccinate and polyvinyl alcohol as the primary and secondary emulsifiers, respectively, were cross-linked by the ionic gelation technique to produce a fluconazole-loaded nanoreservoir system. The formulation of nanoparticles was optimized using response surface methodology. Multiple response simultaneous optimizations using the desirability approach were used to find optimal experimental conditions. The optimal conditions were found to be concentrations of gum cordia (0.85%, w/v), di-octyl sodium sulfosuccinate (9.07%, w/v), and fluconazole (6.06%, w/v). On comparison of the optimized nanosuspension formulation with commercial formulation, it was found to provide comparable in vitro corneal permeability of... [Pg.1209]

Keywords design experiments, design theory, evaluation, methodology, multiple innovations... [Pg.16]

Multiple Metals Testing The samphng method commonly used to measure emissions of metals from stationaiy sources is contained in 40 CFR 266, Appendix IX. The procedure is titled Methodology for the Determination of Metals Emissions in Exhaust Gases from Hazardous Waste Incineration and Similar Combustion Processes. It is also currently pubhshed as Draft EPA Method 29 for inclusion in 40 CFR 60. [Pg.2206]

There is another type of multiple thermal Diels Alder reaction in which the initial monoadduct is involved, either directly or after one transformation, in a second cycloaddition that affords the final polycyclic compounds. These methodologies have been used especially in the synthesis of polycyclic cage compounds. Paquette was the first to report the conversion of 9,10-dihydroful-valene into polyfused cyclopentanoid systems [124],... [Pg.80]

The presence of the catalyst can also favor multiple Diels-Alder reactions of cycloalkenones. Two typical examples are reported in Schemes 3.6 and 3.7. When (E)-l-methoxy-1,3-butadiene (14) interacted with 2-cyclohexenone in the presence of Yb(fod)3 catalyst, a multiple Diels-Alder reaction occurred [21] and afforded a 1 1.5 mixture of the two tricyclic ketones 15 and 16 (Scheme 3.6). The sequence of events leading to the products includes the elimination of methanol from the primary cycloadduct to afford a bicyclic dienone that underwent a second cycloaddition. Similarly, 4-acetoxy-2-cyclopenten-l-one (17) (Scheme 3.7) has been shown to behave as a conjunctive reagent for a one-pot multiple Diels-Alder reaction with a variety of dienes under AICI3 catalysis, providing a mild and convenient methodology to synthesize hydrofluorenones [22]. The role of the Lewis acid is crucial to facilitate the elimination of acetic acid from the cycloadducts. The results of the reaction of 17 with diene... [Pg.104]

Chapter 2 developed a methodology for treating multiple and complex reactions in batch reactors. The methodology is now applied to piston flow reactors. Chapter 3 also generalizes the design equations for piston flow beyond the simple case of constant density and constant velocity. The key assumption of piston flow remains intact there must be complete mixing in the direction perpendicular to flow and no mixing in the direction of flow. The fluid density and reactor cross section are allowed to vary. The pressure drop in the reactor is calculated. Transpiration is briefly considered. Scaleup and scaledown techniques for tubular reactors are developed in some detail. [Pg.81]

This new area of chemistry is still at a very early stage of development with most of the breakthroughs occurring in the last couple of years. The future holds promise for more exciting developments in the use of P=C bonds in polymer science and it is very possible that apphcations may be found for these new types of materials. In addition, an exciting prospect for the future is the further expansion of these methodologies, which are so common for C=C bonds, to other phosphorus-containing multiple bonds and other p-block elements. [Pg.124]

A goal is often achieved by multiple primitive (e.g., valve) operations. All the primitive operations that will together result in violation of a constraint will be Qobberers of that constraint. Consequently, the first step in the quantitative constraint-posting methodology is to identify abstracted operators as the sets of primitive operations. This is accomplished through the following procedure ... [Pg.66]

In this section we describe extensions of the basic learning methodologies introduced in Sections IV and V that, while preserving the same premises and paradigms, enlarge considerably their scope by adding the capability to consider simultaneously multiple objectives. As before, and without loss of generality, we will focus our attention on the coexistence of several quality-related objectives. [Pg.129]

Both situations with categorical and continuous, real-valued performance metrics will be considered and analyzed. Since Taguchi loss functions provide quality cost models that allow the different objectives to be expressed on a commensurate basis, for continuous performance variables only minor modifications in the problem definition of the approach presented in Section V are needed. On the other hand, if categorical variables are chosen to characterize the system s multiple performance metrics, important modifications and additional components have to be incorporated into the basic learning methodology described in Section IV. [Pg.129]

To conclude this section on systems with multiple objectives, we will consider a specific plasma etching unit case study. This unit will be analyzed considering both categorical and continuous performance measurement variables. Provided that similar preference structures are expressed in both instances, we will see that the two approaches lead to similar final answers. Additional applications of the learning methodologies to multiobjective systems can be found in Saraiva and Stephanopoulos (1992b, c). [Pg.134]

We presented extensions and variations of the basic learning methodologies aimed at enlarging their flexibility and cover a number of different situations, including systems where performance is evaluated by categorical or continuous variables, with single or multiple objectives, simple or complex plants containing some type of internal structure and composed of a number of interconnected subsystems. [Pg.153]

In the past, no snitable analytical methodologies were capable of investigating these multiple reactions and even today, the complete extraction and analysis of all the componnds is still a difficult task. The methods for extraction must be optimized for each sample according to the solubility of either phytylated (chlorophylls and pheophytins) or dephytylated (chlorophyllides and pheophorbides) derivatives, often requiring several repeated steps and the use of a single or a mixture of organic solvents. [Pg.430]


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See also in sourсe #XX -- [ Pg.75 , Pg.264 ]




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