Abstract: A method includes authenticating a user of a client device and sending a response to the client device. The response includes browser code configured to retrieve respective first values for a plurality of device properties from the client device. The method also includes storing session information for the user in a memory. The session information includes the first values and criteria for triggering validation of the client device. The method further includes receiving a request, sent from a requesting device, to access a protected resource and determining whether the request is authenticated by determining that the request is associated with the session information and determining that the criteria has been met. Determining whether the request is authenticated also includes retrieving respective second values for the plurality of device properties from the requesting device, and determining whether the second values match the first values to authenticate the request.

Abstract: A method includes authenticating a user of a client device and sending a response to the client device. The response includes browser code configured to retrieve respective first values for a plurality of device properties from the client device. The method also includes storing session information for the user in a memory. The session information includes the first values and criteria for triggering validation of the client device. The method further includes receiving a request, sent from a requesting device, to access a protected resource and determining whether the request is authenticated by determining that the request is associated with the session information and determining that the criteria has been met. Determining whether the request is authenticated also includes retrieving respective second values for the plurality of device properties from the requesting device, and determining whether the second values match the first values to authenticate the request.

Abstract: A method for making a free-standing, single crystal, aluminum gallium nitride (AlGaN) wafer includes forming a single crystal AlGaN layer directly on a single crystal LiAlO2 substrate using an aluminum halide reactant gas, a gallium halide reactant gas, and removing the single crystal LiAlO2 substrate from the single crystal AlGaN layer to make the free-standing, single crystal AlGaN wafer. Forming the single crystal AlGaN layer may comprise depositing AlGaN by vapor phase epitaxy (VPE) using aluminum and gallium halide reactant gases and a nitrogen-containing reactant gas. The growth of the AlGaN layer using VPE provides commercially acceptable rapid growth rates. In addition, the AlGaN layer can be devoid of carbon throughout. Because the AlGaN layer produced is high quality single crystal, it may have a defect density of less than about 107cm?2.

Abstract: A method for making a free-standing, single crystal, aluminum gallium nitride (AlGaN) wafer includes forming a single crystal AlGaN layer directly on a single crystal LiAlO2 substrate using an aluminum halide reactant gas, a gallium halide reactant gas, and removing the single crystal LiAlO2 substrate from the single crystal AlGaN layer to make the free-standing, single crystal AlGaN wafer. Forming the single crystal AlGaN layer may comprise depositing AlGaN by vapor phase epitaxy (VPE) using aluminum and gallium halide reactant gases and a nitrogen-containing reactant gas. The growth of the AlGaN layer using VPE provides commercially acceptable rapid growth rates. In addition, the AlGaN layer can be devoid of carbon throughout. Because the AlGaN layer produced is high quality single crystal, it may have a defect density of less than about 107 cm?2.

Abstract: A method for making a free-standing, single crystal, gallium nitride (GaN) wafer includes forming a single crystal GaN layer directly on a single crystal LiAlO2 substrate using a gallium halide reactant gas, and removing the single crystal LiAlO2 substrate from the single crystal GaN layer to make the free-standing, single crystal GaN wafer. Forming the single crystal GaN layer may comprise depositing GaN by vapor phase epitaxy (VPE) using the gallium halide reactant gas and a nitrogen-containing reactant gas. Because gallium halide is used as a reactant gas rather than a metal organic reactant such as trimethygallium (TMG), the growth of the GaN layer can be performed using VPE which provides commercially acceptable rapid growth rates. In addition, the GaN layer is also devoid of carbon throughout. Because the GaN layer produced is high quality single crystal, it may have a defect density of less than about 107 cm−2.

Abstract: A method for making a free-standing, single crystal, aluminum gallium nitride (AlGaN) wafer includes forming a single crystal AlGaN layer directly on a single crystal LiAlO2 substrate using an aluminum halide reactant gas, a gallium halide reactant gas, and removing the single crystal LiAlO2 substrate from the single crystal AlGaN layer to make the free-standing, single crystal AlGaN wafer. Forming the single crystal AlGaN layer may comprise depositing AlGaN by vapor phase epitaxy (VPE) using aluminum and gallium halide reactant gases and a nitrogen-containing reactant gas. The growth of the AlGaN layer using VPE provides commercially acceptable rapid growth rates. In addition, the AlGaN layer can be devoid of carbon throughout. Because the AlGaN layer produced is high quality single crystal, it may have a defect density of less than about 107 cm−2.

Abstract: An optical switch is described having mirrors that are located over an area having an approximate oval shape. Each mirror is pivotable about a first axis and about a second axis transverse to the first axis. Because of the construction and assembly of each mirror, pivoting about the first axis is more limited than pivoting about the second axis. The area over which the mirrors are located is designed to accommodate pivoting about the first axis and about the second axis such that the area has a length and a width wherein the length is much more than the width. In addition, pivoting about the first axis limits pivoting about the second axis and pivoting about the second axis limits pivoting about the first axis. Because pivoting about one axis limits pivoting about another axis, the area over which the mirrors are located has an oval shape as opposed to a rectangular shape.

Abstract: A method for making a free-standing, single crystal, gallium nitride (GaN) wafer includes forming a single crystal GaN layer directly on a single crystal LiAlO2 substrate using a gallium halide reactant gas, and removing the single crystal LiAlO2 substrate from the single crystal GaN layer to make the free-standing, single crystal GaN wafer. Forming the single crystal GaN layer may comprise depositing GaN by vapor phase epitaxy (VPE) using the gallium halide reactant gas and a nitrogen-containing reactant gas. Because gallium halide is used as a reactant gas rather than a metal organic reactant such as trimethygallium (TMG), the growth of the GaN layer can be performed using VPE which provides commercially acceptable rapid growth rates. In addition, the GaN layer is also devoid of carbon throughout. Because the GaN layer produced is high quality single crystal, it may have a defect density of less than about 107 cm−2.

Abstract: The invention concerns a process for the isomerization of humulon in a carbon dioxide-hops extract and a process for the isolation of isohumulon from the isomerized carbon dioxide-hops extract. Aluminium or an aluminium compound, preferably aluminium trioxide is added to the carbon dioxide-hops extract in such a concentration that the mole ratio of aluminium: alpha acid (alpha humulon) amounts to from 1:0.1 to 1:6. The mixture is then treated with high alkali hydroxide concentration at a temperature of from 80.degree. to 160.degree. C.Isohumulon is obtained from the extract by adding so much tempered water that the isohumulon share amounts to 1 to 10% and the temperature is reduced to 40.degree. to 45.degree. C., and after further cooling to room temperature, the alkali isohumulons are purified from the other components in conventional manner and optionally are transformed in the conventional way into isohumulons.

Abstract: The invention relates to a threading tool for internal threads with a cutter holder which is displaceably mounted on a cutter holder carrier shaft co-axial to the main axis of the rotatable tool which coincides with the thread axis during the cutting process, whereby the said cutter holder shaft is moved forwards and backwards periodically with the forward feed corresponding to the thread pitch in the direction of the main axis in the thread chasing operation by a cam control with a camshaft co-axial to the cutter holder shaft and rotating with a differential speed relative thereto, whereby through a corresponding radial displacement of the cutter holder the cutter is raised during return travel and in the thread chasing operation is set to engage lower and lower from one thread chasing operation to the next up to the final cutting depth.

Abstract: The process employs both silicon dioxide and silicon nitride layers used for selectively masking areas to be etched in order to allow a single photomask to be used for defining areas having different conductivities simultaneously, thereby eliminating problems caused by misregistry between photomasks.

Abstract: A workshop installation in which a user can service equipment, machines, vehicles and the like comprising one or more enclosures each having a single access space with a displaceable barrier thereat. The barrier is normally retracted to allow free entry into the respective enclosure via the access space and it is closable after entry into the space. A plurality of tools are supported in tool carriers within the enclosure for utilization by the user within the enclosure. A pre-payment device in the enclosure is coupled to the barrier and the tool supports for allowing removal of the tools after sufficient payment has been made in the pre-payment device corresponding to a pre-determined period of time. A barrier locking device is actuated when a tool has been removed from the tool supports. An electrical warning circuit is provided for each enclosure and is activated when the predetermined period of time of the pre-payment device has expired and the tools have not been returned to the tool supports.