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P C Schulz

Publications and source records attributed to P C Schulz.

4 recordsLinked to original sources

Iron dissolution in aqueous AOT solution.

The effects of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) on the electrochemical behavior of iron were studied by potentiodynamic and potentiostatic techniques and open-circuit potential measurements. Experiments were made in both neutral and alkaline AOT solutions (pH 7 and pH 12). It was found that AOT-assisted dissolution is initiated on a passivated iron surface and that the oxidation current leads to the formation of a gel-like film on the electrode surface. This dissolution process was investigated as a function of pH, potential, and electrode rotation rate and the corrosion products were characterized by polarizing microscopy, SEM/EDX, and IR spectroscopy. The gel-like material is a mixed NaAOT-Fe(AOT)3 lamellar mesophase and a structure for this mesophase is proposed.

Journal Article↗

Computational study of the structure and behavior of aqueous mixed system sodium unsaturated carboxylate-dodecyltrimethylammonium bromide.

The mixed surfactant system sodium 10-undecenoate (SUD)-dodecyltrimethylammonium bromide (DTAB) was studied by computational simulation to determine the composition and structure of the mixed microstructures. Results were contrasted with experimental data obtained from literature and our own laboratory. The modelization predicts spherical or cylindrical micelles with a preferential composition of SUD-DTAB of about 1:2, while the system predicts a lamellar structure with a proportion of 1:1 when SUD is replaced by the saturated soap sodium undecanoate. The model also predicts the deep inclusion of bromide ions in the micelle Stern layer. All predictions were in agreement with previous experimental results.

Journal Article↗

Immunoglobulin therapy for autoimmune neutropenia in Hodgkin's disease.

We describe a patient with recurrence of Hodgkin's disease and severe liver disease of unknown origin in whom autoimmune neutropenia developed. Because of possible seronegative viral hepatitis he was treated with high-dose intravenous immunoglobulin instead of steroids. He responded with a prompt but transitory increase of the neutrophil count and recovered completely after chemotherapy.

Adult↗

[Dose-response relation of gallopamil in comparison with nifedipine, diltiazem and tiapamil in patients with coronary heart disease].

For effective treatment of coronary heart disease with calcium antagonists, knowledge of both the dose-response relationship of a remedy and equipotent dosage for comparison of different drugs is necessary. We performed controlled studies to evaluate the influence of single oral doses of calcium antagonists on ischemic ST-depression (calculated as the mean of all exercise and recovery minutes = mean ST-depression) in exercise ECGs of patients with proven CHD and stable angina pectoris. Ergometries were carried out under constant conditions, particularly with individually constant work load and duration. All calcium antagonists reduced ischemic ST-depression during ergometry dose-dependent when compared to placebo. Diltiazem: 90 mg: 6% (n.s.), 120 mg: 19% (n.s.) und 180 mg: 26% (p less than 0.025); gallopamil: 25 mg: 19% (n.s.), 50 mg: 34% (p less than 0.01) und 100 mg: 57% (p less than 0.0025); nifedipine-Cps.: 5 mg: 17%, 10 mg: 33% und 20 mg: 42%; nifedipine-Tbl.: 20 mg: 8% (p less than 0.05), 40 mg: 23% (p less than 0.057 und 60 mg: 31% (p less than 0.05); tiapamil: 300 mg: 30% (p less than 0.05) und 600 mg: 60% (p less than 0.01). As the result of our findings, comparable antiischemic effects can be expected with 120 mg diltiazem, 50 mg gallopamil, 20 mg nifedipin as capsule or 60 mg nifedipin as tablet and 600 mg tiapamil.

Adult↗