Publications by authors named "Peter Janknecht"

Introduction: The aim was to construct a model cornea by CAD and finite element software to find out how the intraocular pressure compares to the forces for applanation at the outside of the model cornea. These data were to be compared to the Dresdner correction formula. Thereby, it was possible to find out whether the model was plausible and to find hints as to why a correction for how the intraocular pressure depends on the corneal thickness is necessary at all.

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In response to increasingly stringent restrictions for drinking water quality, a parallel operation of two common technologies, low-pressure reverse osmosis (LPRO) and activated carbon filtration (ACF), was investigated in a comprehensive five-month pilot study for the removal of 32 typical trace organic contaminants (TrOCs) from Rhine bank filtrates employing a semi- technical plant. TrOCs have been divided into three groups: polyfluorinated aliphatic compounds; pharmaceuticals, pesticides and metabolites; in addition to volatiles, nitrosamines and aminopolycarboxylic acids, which were also examined. The net pressure behavior, normalized salt passage and rejection of TrOCs by LPRO were investigated and compared with ACF operation.

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Humic acids (HAs) content of raw water is an important analytical parameter in water treatment facilities because HAs in the presence of chlorine may lead to the formation of dangerous by-products (e.g., trihalomethanes).

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Purpose: Facilitation of vitrectomy by vitreolytic enzymes may be of great value in complicated or office-procedure vitreo-retinal surgery. In this study, we quantified and compared the effect of hyaluronidase, chondroitinase, and plasmin pre-incubation on vitrectomy rate and explored potential retinal damage.

Methods: Freshly enucleated pigs eyes were incubated (1 or 3 hours) with an intravitreally injected enzyme or control solution.

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The utilization of micro- and ultrafiltration with polymeric membranes for treatment of industrial cutting oil emulsion was investigated. The performance of 14 different membranes with pore sizes in the range of 1-800 nm, representing 8 different materials and varying hydrophobicity, was determined experimentally. Membrane permeances between 1.

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