Patents Assigned to University of Waterloo
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Patent number: 6405143Abstract: A method for determing the potential in a three-dimensional domain containing a source domain of source particles and a target domain of target particles involves assigning the source particles into source particle clusters and the target particles into target particle clusters, assigning a collection point to each of the clusters, and determing the inverse distance from each particle to the collection point of its respective cluster. A pseudo-particle representative of each particle within the cluster is defined at the collection point of each cluster in accordance with the determined inverse distances and the charge-like measure of each of the particles. The potential, and/or its gradient, at any of the target particles is then determined from the position and the charge-like measure of the associated pseudo-particle.Type: GrantFiled: August 13, 1999Date of Patent: June 11, 2002Assignee: The University of WaterlooInventors: Hoan Huu Pham, Arokia Nathan
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Patent number: 6393925Abstract: A groundwater velocity probe is provided comprising a surface with a first portion and a second portion, an injector for injecting a tracer proximate the first portion, a detector for detecting the tracer proximate the second portion, and a timer for measuring time elapsed between injecting the tracer and detecting the tracer.Type: GrantFiled: March 17, 2000Date of Patent: May 28, 2002Assignee: University of WaterlooInventor: John Frederick Devlin
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Patent number: 6287472Abstract: Groundwater, or other water contaminated with chlorinated organic contaminants, is passed through a permeable body of iron particles. The particles are coated with nickel, but the coating is incomplete, in that, in patches, the iron is directly exposed. The contaminants break down under prolonged proximity to the iron, the nickel enhancing the catalytic effect. The rate of breakdown is much faster than when bare iron particles were used. When the nickel is alloyed with phosphorus, or boron, even more rapid breakdown rates are achieved.Type: GrantFiled: April 16, 1998Date of Patent: September 11, 2001Assignee: University of WaterlooInventors: Robert W Gillham, Marek S Odziemkowski, Stephanie F O'Hannesin
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Patent number: 6274048Abstract: Lenses of DNAPL suspended on clay strata in a sandy aquifer are treated with potassium permanganate. The solution is injected out into the aquifer from a port, and forms a horizontal disc of treatment liquid. The (heavy) liquid then gradually percolates down onto the DNAPL lens.Type: GrantFiled: March 22, 2000Date of Patent: August 14, 2001Assignee: University of WaterlooInventors: Beth Louise Parker, Matthew David Nelson, John Anthony Cherry
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Patent number: 6268448Abstract: The present invention relates to the use of complexes of transition metals having a ligand containing a phosphorus or arsenic atom bound to the transition metal through an oxygen atom, or an amido radical. The complexes may be activated with conventional activators and are useful in solution, slurry and gas phase polymerization of olefins.Type: GrantFiled: August 9, 1999Date of Patent: July 31, 2001Assignees: University of Waterloo, Nova Chemical CorporationInventors: Scott Collins, Rainer Vollmerhaus, Qinyan Wang
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Patent number: 6232848Abstract: An integrated radio frequency (RF) coupling scheme is provided for realizing low voltage RF integrated circuits. According to the invention, on-chip capacitively coupled resonant elements are used to DC isolate circuit block elements which are required to be connected in series and share a common DC current. The coupling scheme according to the present invention may be applied to several commonly used RF integrated circuit topologies such as low noise amplifiers and mixers.Type: GrantFiled: December 17, 1998Date of Patent: May 15, 2001Assignee: The University of WaterlooInventor: Tajinder Manku
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Patent number: 6214229Abstract: A new method of forming mask ROM in the manufacture of an integrated circuit device has been achieved. A semiconductor substrate is provided with field oxide areas defined and a gate oxide layer overlying the semiconductor substrate. A gate electrode layer is deposited overlying the gate oxide layer. The gate electrode layer and the gate oxide layer are patterned to form gate electrodes. Ions are implanted to form source and drain junctions. A buffer layer is deposited overlying the gate electrodes, the source and drain junctions, and the field oxide areas. The buffer layer is etched down to expose the gate electrodes while leaving a protective thickness of the buffer layer overlying the source and drain junctions. Ions are implanted through the gate electrodes into the semiconductor substrate to selectively code the mask ROM devices and to complete the mask ROM devices in the manufacture of the semiconductor device. A coding mask controls the ion implantation to selectively code the mask ROM.Type: GrantFiled: November 3, 1998Date of Patent: April 10, 2001Assignee: University of WaterlooInventor: William Dean Robertson
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Patent number: 6194343Abstract: The present invention provides a tethered bridged metallocene compound in which the tether typically comprises a segment of the formula —(R2)d—(CH2CH2)e(CH═CH)f wherein R2 is an alkylene or phenylene group, and d, e and f are 1 or 0. One end of the tether reacts with a silane bridged metallocene compound and the other reacts with the support. The activated metallocene compound is capable of producing a polymer having a narrow molecular weight distribution.Type: GrantFiled: March 11, 1999Date of Patent: February 27, 2001Assignee: University of WaterlooInventors: Scott Collins, Jun Tian
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Patent number: 6184982Abstract: An in-torch vaporization sample introduction system for introducing a sample to be analyzed into a spectrometer, comprising sample holder means for carrying the sample to be analyzed, a modified Fassel-type torch having a plasma fed by inert gas through outer and intermediate feed channels in an enlarged gas tube, an inner axial tube having one end open adjacent the plasma and an opposite end open for receiving the sample holder means for feeding the sample to the plasma, the inner axial tube tapering to a reduced diameter adjacent the one end to form a well defined channel for feeding the sample to the plasma means for positioning the sample holder means in the inner axial tube a predetermined distance below the plasma, and means for sealing the opposite end of the inner axial tube and means for vaporizing the sample.Type: GrantFiled: May 9, 1997Date of Patent: February 6, 2001Assignee: The University Of WaterlooInventor: Vassili Karanassios
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Patent number: 6114445Abstract: The hydrosilylation of terminal double bonds in polypropylene (PP) or other polymers is effected in the melt phase. The double bonds were created by peroxide initiated degradation of PP in an extruder or a batch mixer. A hydride terminated polydimethylsiloxane is employed as a model substance to investigate the feasibility of hydrosilylating the terminal double bonds of the degraded polypropylene. The reaction may be carried out in three different reactors, namely a hot press, a batch mixer and a screw extruder. Two different reaction mechanisms may be used to effect the hydrosilylation reaction, namely a radical chain addition mechanism and a platinum catalysed mechanism with a colloid forming catalyst, platinum divinyltetramethyldisiloxane (Karstedt's catalyst). Catalytic amounts of a peroxide initiator are able to initiate the addition of silanes to the double bonds of the degraded polypropylene. Both reactions, namely degradation and hydrosilylation, may be performed simultanously.Type: GrantFiled: December 17, 1998Date of Patent: September 5, 2000Assignee: University of WaterlooInventors: Costas Tzoganakis, Hauke Malz
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Patent number: 6064871Abstract: A low power passive .SIGMA..DELTA. converter for baseband applications and with a built in mixer for direct conversion. For direct conversion, low power consumption is achieved by adopting a passive loop filter for the .SIGMA..DELTA. converter together with merging the sampling and mixing functions together utilizing a specially designed mixer. With a passive loop filter, the only gain element in the loop is a high gain, high speed, low noise comparator. The mixer can be located outside of the feedback loop, although according to one aspect of the present invention, the mixer is incorporated inside the feedback loop. For baseband applications, the same design is utilized with a simple sampling switch instead of a mixer for processing baseband signals with low power consumption.Type: GrantFiled: January 2, 1996Date of Patent: May 16, 2000Assignee: University Of WaterlooInventor: Bosco Leung
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Patent number: 6028454Abstract: A dynamic current mode circuit for low-voltage and high performance VLSI applications, comprising a MOS current mode logic block and dynamic circuitry for precharging the outputs of the MOS current mode logic block, cross-coupled latches for enhancing performance of the MOS current mode logic block during an evaluation phase thereof, and a dynamic current source for enhanced speed and low power consumption.Type: GrantFiled: June 12, 1998Date of Patent: February 22, 2000Assignee: The University of WaterlooInventors: Mohamed Elmasry, Mohamed Allam
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Patent number: 5999581Abstract: A direct digital frequency synthesizer for generating a digital sine or cosine function waveform receive digital input. Memory stores digital samples along portions of sine and cosine function waveforms. The memory outputs the digital samples in response to a first portion of the digital input. Control logic is responsive to the digital input and controls the output of the digital samples from the memory to allow digital samples along a complete cycle of the sine or cosine function waveform to be output even though only portions of the sine and cosine function waveforms are stored in the memory. A linear interpolator receives a second portion of the digital input and modifies digital samples output by the memory to generate intermediate digital samples between the digital samples stored in the memory to improve accuracy.Type: GrantFiled: September 29, 1995Date of Patent: December 7, 1999Assignee: University of WaterlooInventors: Abdellatif Bellaouar, Michael S. Obrecht, Mohamed I. Elmasry
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Patent number: 5990691Abstract: An integrated circuit is set forth including a plurality of circuit elements interconnected by conductors and at least one resistive element operably connected to a location within the circuit. Upon an event occurring at the location, such as the activation of a circuit element, current is passed through the resistive element thereby elevating the temperature of the resistive element to cause incandescence so as to permit optical detection of the event.Type: GrantFiled: May 14, 1997Date of Patent: November 23, 1999Assignee: University of WaterlooInventors: Werner Joerg, Arokia Nathan
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Patent number: 5972679Abstract: A plurality of polypeptides derived from intercellular spaces of plant cells having frost tolerance. Some of the polypeptides are ice nucleators for developing ice crystals in extracellular spaces of plant tissue, some of the polypeptides are antifreeze components which control ice crystal growth in extracellular spaces and some of the polypeptides are enzymes which adapt plant cell walls to function differently during formation of ice crystals in plant intercellular spaces.Type: GrantFiled: June 7, 1995Date of Patent: October 26, 1999Assignee: University of WaterlooInventor: Marilyn Griffith
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Patent number: 5957625Abstract: The barrier is waterproof, and is used to contain contaminated groundwater within an enclosure. Steel elements are pile driven, the elements having rolled-over edge forms (5,6) which interengage. Upon interengagement, an enclosed hole (90) is created which extends from top to bottom of the piled elements. A scraper (19) on the junior element (8) cleans dirt out of the hole as the junior is driven down alongside the adjacent senior element (7). The hole may be cleaned out by inserting a hose pipe to the bottom of the hole (90) and flushing through with water. Then, a sealant is injected into the hole, using an injection tube in the hole. The interengagement of the edge forms (5,6) of the elements is such that the hole formed by the interengagement is constrained to its nominal size and shape throughout the whole height of the barrier.Type: GrantFiled: May 29, 1997Date of Patent: September 28, 1999Assignee: University of WaterlooInventor: Enoch Sam Vales
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Patent number: 5911546Abstract: The barrier is waterproof, and is used to contain contaminated groundwater within an enclosure. Steel elements, are pile driven, the elements having rolled-over edge forms (5,6) which interengage. Upon interengagement, an enclosed hole (90) is created which extends from top to bottom of the piled elements. A scraper (19) on the junior element (8) cleans dirt out of the hole as the junior is driven down alongside the adjacent senior element (7). The hole may be cleaned out by inserting a hose pipe to the bottom of the hole (90) and flushing through with water. Then, a sealant is injected into the hole, using an injection tube in the hole. The interengagement of the edge forms (5,8) of the elements is such that the hole formed by the interengagement is constrained to its nominal size and shape throughout the whole height of the barrier.Type: GrantFiled: October 17, 1996Date of Patent: June 15, 1999Assignee: University of WaterlooInventor: Enoch Sam Vales
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Patent number: 5876606Abstract: The metal oxide media includes oxides and hydroxides of iron, and other metals. The material is derived from basic-oxygen steel-making process, and includes a high calcium content. The oxide surfaces facilitate the adsorption of phosphorus, and the increased pH facilitates the precipitation of calcium and other phosphates. The oxides are a catalyst for converting organic phosphorus to inorganic form. Limestone may be added to the oxides, to ensure a long-term source of calcium, and to maintain high pH for long periods.Type: GrantFiled: November 12, 1996Date of Patent: March 2, 1999Assignee: University of WaterlooInventors: David William Blowes, Carol Jane Ptacek, Michael John Baker
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Patent number: 5868941Abstract: Treatment of halogenated hydrocarbon contaminants in groundwater is accomplished by passing the water through a bed of granular iron (43). An electrical circuit (47) is promoted for providing electrons for reducing the contaminant. The circuit may be made using a DC supply, by configuring an electrolytic circuit, or by providing a layer of a second metal such as zinc placed next to the iron bed, thereby creating a galvenic circuit.Type: GrantFiled: October 18, 1996Date of Patent: February 9, 1999Assignee: University of WaterlooInventors: Robert W Gillham, Robert M Focht, Pascale M Bonin, Mark D Pritzker
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Patent number: RE36553Abstract: In the conventional incineration of solid waste materials, flyash present in the combustion products gas stream catalyzes the formation of toxic dioxins from chlorinated organic materials. By providing a catalyst poison, such as carbon disulphide, in association with the flyash, typically by spraying onto the solid wastes prior to incineration, the catalytic effect is decreased, resulting in decreased dioxin formation.Type: GrantFiled: January 16, 1996Date of Patent: February 8, 2000Assignee: University of WaterlooInventors: Francis W. Karasek, Leslie C. Dickson, Otto Hutzinger