Boettcher Alfred

Bio: Boettcher Alfred is an academic researcher. The author has contributed to research in topics: Glass tube & Tube (fluid conveyance). The author has an hindex of 2, co-authored 4 publications receiving 26 citations.

Solar collector with photovoltaic pile

Abstract: a. Solar collector with photovoltaic pile. b. Solar collector characterised in that the photovoltaic cell 16, 18 is placed in a closed glass tube 12, on a metal support 14 which is connected in a heat-conducting manner to a tube 20 which can be cooled directly or indirectly. c. The invention relates to a solar collector with photovoltaic pile, especially for producing hot water.

Trocar sleeves having a ball valve

Abstract: A trocar sleeve of the kind having a widened part forming a housing between the distal portion of the sleeve and its proximal portion, which latter extends from a plug for the widened housing part, and a ball valve in the widened housing part which ball valve is closable by resilient means and which is openable by a trocar passing through the sleeve. In this invention, the widened part forming the housing receives an insert of U-shaped cross-section which is securable to the plug to stress an inserted sealing gasket of deformation-resistant plastics material which is to be drilled through to form a valve seating. The space in the U formed by the insert forms a space for the ball of the ball valve to move in, the ball, before the insert is screwed to the plug, being connected to a shaft insertable in the insert and carrying a tangentially loaded helical spring and being placed under stress by connecting the insert to the plug.

Semiconductor light receiving device

Abstract: A semiconductor light receiving device, including; a photo diode having a polyimide film as a surface protection film, and a hermetically sealed package including the photo diode in an ambient gas including oxygen.

Method for making fuel cladding having zirconium barrier layers and inner liners

Abstract: The present invention provides a cladding having an outer circumferential substrate, a zirconium barrier layer metallurgically bonded to the inside surface of the substrate and an inner circumferential liner metallurgically bonded to the zirconium barrier The inner circumferential liner is more ductile than conventional Zircaloy The low ductility of the inner circumferential liner is obtained by using a zirconium alloy containing a low tin content (eg less than 12% by weight) and/or a low oxygen content (eg less than 1000 ppm) The inner circumferential liner is less than about 25 micrometers thick

Apparatus for guiding surgical instruments into a surgical site and blocking escape of fluids from the site

Abstract: Apparatus for guiding insertion of surgical instruments into a surgical site while blocking escape of fluids, including gas under pressure, therethrough from the surgical site. A generally Y-shaped housing comprises an elongate instrument guide having a distal end insertable in the surgical site and an elongate instrument passage through which elongate instruments are insertable into the surgical site. A valve seat is provided in the instrument passage. A valve member is movable into contact with the valve seat for blocking escape of fluid from the surgical site therepast along the instrument passage when no instrument occupies such instrument passage. Such housing includes a tubular valve guide having an elongate valve passage intersecting the instrument passage and along which the valve member is movable toward and away from the valve seat. The valve member is urged resiliently along the valve passage toward the valve seat for closing the instrument passage when no surgical instrument is in the instrument passage and for resiliently allowing a surgical instrument inserted into the instrument passage to push aside the valve member, back into the valve passage, to allow continued insertion of the surgical instrument past the valve member into the surgical site.

Heat transfer device

Abstract: A heat transfer device having a working fluid capable of circulating around a fluid flow path, the circulation around the fluid flow path bringing the working fluid in and out of thermal contact with a heat source, the heat transfer device comprising: a fluid containing portion internally defining a working fluid flow path; a heat source at least partially in thermal contact with the fluid containing portion; a gas substance generator at least partially within the fluid containing portion, and arranged to generate bubbles of vapor capable of driving the working fluid along a portion of the working fluid flow path in thermal contact with the heat source; wherein, in use, the driven working fluid absorbs heat from the heat source and transports the heat away from the heat source; and the driven working fluid returns to the gas substance generator to be recycled about the fluid flow path.