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R F Hirsch

Publications and source records attributed to R F Hirsch.

5 recordsLinked to original sources
PubMed1997

Refining hollow obturator base using light-activated resin.

The disadvantages of an open-type hollow obturator include difficulty in polishing and cleaning of the internal surface, food accumulation in the hollow obturator and inability to obtain support from the superior aspect in the defect area. This article describes and easy time-saving procedure that uses visible light-activated denture base materials as a reline material to close an open type interim obturator. This procedure can be used successfully for both late stage interim obturators and/or for correcting leakage problems for patients who wear definitive obturators.

Acrylic Resins↗
PubMed1983

Ion-sensitive electrode potentiometry of organic anions: application to quantitative structure-activity relationships.

Ion-sensitive electrode potentiometry is proposed for determination of substituent constants for structural modifications of organic acids. A liquid membrane anion-sensitive electrode responds reproducibly to a wide range of carboxylate and sulfonate ions. Fragment constants for the addition of a methylene group to aromatic and aliphatic acids are -2.4 and -3.3 +/- 0.15 kJ/mol, respectively. Agreement is observed between these constants and those determined by other techniques, including partitioning studies in biphasic systems, suggesting the use of potentiometry for quantitative structure-activity relationship studies. Furthermore, the electrode measurements correlate with biological effects resulting from hydrophobic interactions.

Anions↗