Francisco Salto

N-Pyrrolyl Derivative Acids Chromatography

Abstract A determination is made on the effects of the variation of pH, methanol %, contents of tetrabutylammonium salts, ionic strength and counterion nature of the mobile phase quaternary ammonium salt, on the retention of a series of analgesics formed by N-pyrrolyl derivative acids through a column constituted by 10 μ irregular particles of octadecyl silica. The results obtained are applied to mixture separation of said acids.

An Interpretation of Łukasiewicz’s 4-Valued Modal Logic

A simple, bivalent semantics is defined for Łukasiewicz’s 4-valued modal logic Łm4. It is shown that according to this semantics, the essential presupposition underlying Łm4 is the following: A is a theorem iff A is true conforming to both the reductionist (rt) and possibilist (pt) theses defined as follows: rt: the value (in a bivalent sense) of modal formulas is equivalent to the value of their respective argument (that is, ‘ A is necessary’ is true (false) iff A is true (false), etc.); pt: everything is possible. This presupposition highlights and explains all oddities arising in Łm4.

Dual Equivalent Two-valued Under-determined and Over-determined Interpretations for Łukasiewicz’s 3-valued Logic Ł3

AbstractŁukasiewicz three-valued logic Ł3 is often understood as the set of all 3-valued valid formulas according to Łukasiewicz’s 3-valued matrices. Following Wojcicki, in addition, we shall consider two alternative interpretations of Ł3: “well-determined” Ł3a and “truth-preserving” Ł3b defined by two different consequence relations on the 3-valued matrices. The aim of this paper is to provide (by using Dunn semantics) dual equivalent two-valued under-determined and over-determined interpretations for Ł3, Ł3a and Ł3b. The logic Ł3 is axiomatized as an extension of Routley and Meyer’s basic positive logic following Brady’s strategy for axiomatizing many-valued logics by employing two-valued under-determined or over-determined interpretations. Finally, it is proved that “well determined” Łukasiewicz logics are paraconsistent.

Ticket Entailment plus the mingle axiom has the variable-sharing property

The logic TM is the result of adding the mingle axiom to Ticket Entailment logic, T. In the present paper, it is proved that TM has the variable-sharing property (vsp). Ternary relational semantics for TM is provided. Finally, an interesting extension of TM with the vsp is briefly discussed.

Ion Interaction Chromatography of Clavulanic Acid on a Poly(Styrene-Dinvinylbenzene) Adsorbent in the Presence of Tetrabutylammonium Salts

Abstract The effect of tetrabutylammonium, inorganic coanions, and inert electrolytes, on the clavulanic anion retention on PRP-1 column, formed with 10 μm spherical uniform particles from a polystyrene-divinylbenzene with high pore volume and large surface area, is studied. The results obtained are applied to the chromatographic separation of clavulanic acid from β-lactamic antibiotics and to the determination of clavulanate anion in fermentation broths.

A modal restriction of R-Mingle with the variable-sharing property

A restriction of R-Mingle with the variable-sharing property and the Ackermann properties is defined. From an intuitive semantical point of view, this restriction is an alternative to Anderson and Belnap’s logic of entailment E.

Correlations Between the Distribution Coefficients and the Capacity Factors in Reverse HPLC of N-Pyrrolyl Derivative Acids

Abstract The distribution coefficients in octanol-water of the dissociated and non-dissociated forms for eleven N-pyrrolyl derivative acids which possess analgesic properties and plaquetary antiaggregating agents are determined. Likewise the capacity factors have been determined by reverse HPLC, and a study has been made of relationship between the two types of coefficients.