Abstract: A filtering membrane has a supporting structure comprising filaments and is coated with a dope to produce a polymeric membrane layer. Some or all of the filaments comprise a second polymer that is soluble or swellable in a solvent of the dope. The supporting structure may be braided with yarns. One or more yarns may comprise filaments comprising the second polymer. In one example, a braided tubular support is coated with a dope based on PVDF in NMP. Some or all of the yarns of the braid are made of bi-component core-sheath PET-PVDF filaments. With as few as 4% of the yarns in the braid made of the bicomponent filaments, peel strength and pull force of the membrane is improved relative to a braid made entirely of PET yarns. In experimental examples, unpeelable composite membranes were produced. The membrane may be used, for example, for water or wastewater filtration applications.

Abstract: A filtration membrane is coated with a polymer made from a compound comprising a benzenediol or a substituted phenol, such as catechol. The polymer deposition process comprises exposing the membrane to the compound in an aqueous alkaline solution. A membrane module may be immersed in the solution. Optionally, the solution is aerated. The polymer coating is reasonably durable in aqueous environments but may be removable. In an example, a module of PVDF based outside-in hollow fiber membranes was coated with poly(catechol). The membranes had a reduced fouling rate and could be maintenance cleaned with water or a dilute oxidant solution. The polycatechol coating could be oxidized by cleaning the membrane with a hypochlorite solution and re-coated. The modified membranes may be used, for example, in water or wastewater treatment. A filtration process includes steps of oxidizing and re-applying the coating after the membrane has been in use.

Abstract: A filtering membrane has a supporting structure comprising filaments and is coated with a dope to produce a polymeric membrane layer. Some or all of the filaments comprise a second polymer that is soluble or swellable in a solvent of the dope. The supporting structure may be braided with yarns. One or more yarns may comprise filaments comprising the second polymer. In one example, a braided tubular support is coated with a dope based on PVDF in NMP. Some or all of the yarns of the braid are made of bi-component core-sheath PET-PVDF filaments. With as few as 4% of the yarns in the braid made of the bicomponent filaments, peel strength and pull force of the membrane is improved relative to a braid made entirely of PET yarns. In experimental examples, unpeelable composite membranes were produced. The membrane may be used, for example, for water or wastewater filtration applications.

Abstract: There is disclosed a microscope causing a variable-magnification optical system provided in the optical path of the microscope and having at least an optical member movable in the direction of optical axis of the optical path, to vary the magnification of the observed image of the specimen, a rotary knob for moving the optical member in the direction of optical axis, a position indicating device for indicating when the rotary knob is in a rotary position where the optical member is in a predetermined position and a varying device for varying the predetermined position.

Abstract: The present invention relates to a novel felt construction for use in the press section of the papermaking machine. More particularly, this invention has to do with a papermakers' felt having a paper-sheet-contacting layer comprised of substantially flat fibers joined by any suitable means to either a woven or nonwoven intermediate batt layer and/or base layer.