Patents Represented by Attorney Arthur A. Smith, Jr.
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Patent number: 4080264Abstract: This inventin provides a means for determining the concentration of any of a wide range of antibody or antigen molecules with a high degree of specificity, accuracy and sensitivity. Antigen or antibody concentration is determined by effecting an agglutination reaction in a liquid medium and determining the mean diffusion constant of the agglutinated reaction product by quasi-elastic light scattering spectroscopy. The measured mean diffusion constant then is compared with a standard quantitative relationship between mean diffusion constant and concentration of the antigen or antibody being tested. By this means one may specifically ascertain the absolute concentration of the antigen or antibody in question in the sample being analyzed. In addition to detecting antigen or antibody molecules, the process of this invention can be used to determine the concentration of any substance capable of specifically promoting or inhibiting an agglutination reaction such as viruses, white blood cells or the like.Type: GrantFiled: March 1, 1976Date of Patent: March 21, 1978Assignee: Massachusetts Institute of TechnologyInventors: Richard J. Cohen, George B. Benedek
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Patent number: 4076866Abstract: A method of growing films composed of low-melting-point materials from a feed material whose constituents have large differences in vapor pressure. In the system disclosed, the feed material is contained within an ampoule and delivered in the form of a melt to a heated environment whose temperature is higher than the temperature of vaporization of the constituent of the feed material having the highest vaporization temperature, thereby to effect flash vaporization of the liquid and thus avoid changes in composition or phase separation.Type: GrantFiled: April 30, 1975Date of Patent: February 28, 1978Assignee: Massachusetts Institute of TechnologyInventors: Nicolaos S. Platakis, Harry C. Gatos
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Patent number: 4075846Abstract: A thermal engine with entrapped working medium is a device with a principle element in the form of a continuous yieldable belt whose tension and length are responsive to temperature due to the property of the working medium entrapped by the belt. This yieldable belt is then wrapped in sequence over several rollers which are coupled together rigidly by suitable mechanical means to give differential speeds among the rollers. Driven in this manner the yieldable belt will undergo cyclic change in tension and stretch while passing over the rollers in sequence. When heat is applied and removed in proper phasing with the cyclic variation of the mechanical properties exhibited by the belt and the entrapped working medium, the device will act as an engine with adequate power output at the shaft coupled to one of the rollers.Type: GrantFiled: May 4, 1976Date of Patent: February 28, 1978Assignee: Massachusetts Institute of TechnologyInventor: Yao Tzu Li
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Patent number: 4076916Abstract: A method is disclosed for fluorinating functionalized polymeric materials which contain pendant ester, carboxylic acid, acid halide or acid anhydride groups. Non-fluorinated or partially fluorinated polymers containing such pendant groups are placed in a direct fluorination apparatus and a mixture of elemental fluorine and an inert gas is passed over the material using La-Mar fluorination techniques. The polymer backbone is perfluorinated while the pendant groups are maintained or converted to acid fluoride groups; in either case, the pendant noncarboxylic acid groups are easily convertible to such acid groups by hydrolysis. These fluorinated functionalized polymers are useful, per se, as ion exchange membranes, solid electrolytes, conductive films, etc., and, in addition, various reactants can be tacked onto such fluorinated polymers thereby making them useful in many other applications.Type: GrantFiled: November 3, 1975Date of Patent: February 28, 1978Assignee: Massachusetts Institute of TechnologyInventor: Richard J. Lagow
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Patent number: 4075706Abstract: A continuously programmable matched filter device using a piezoelectric substrate capable of propagating acoustic wave signals on a selected surface thereof and a semiconductor substrate mounted adjacent and spaced from such surface. Means are provided for altering the conductivity pattern in the semiconductor substrate in accordance with the wave form of a reference wave signal so that a representation of the reference wave is effectively stored therein. Storage of the reference is achieved with electrostatic charge by supplying a plurality of electrons in the spatial region between the substrates or by manipulating the carriers in the semiconductor material into trapping states in order to produce such altered conductivity pattern. A second signal can thereupon be propagated along the piezoelectric substrate to interact with the stored reference conductivity pattern to provide either correlation or convolution operation depending on the direction of propagation thereof along the piezoelectric surface.Type: GrantFiled: March 31, 1976Date of Patent: February 21, 1978Assignee: Massachusetts Institute of TechnologyInventors: Ernest Stern, Richard C. Williamson, Henry I. Smith
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Patent number: 4069732Abstract: An electric guitar is described which provides signals from each of its electrically conducting strings by the cutting of magnetic field lines. The magnetic fields are produced by removably mounted permanent magnets which produce concentrated fields. The return wire or wires of the strings are near the surface of the neck. Various circuit configurations are used to minimize noise pickup, to combine the signals from each signal and to modify the sound produced by each string.Type: GrantFiled: September 8, 1975Date of Patent: January 24, 1978Assignee: Massachusetts Institute of TechnologyInventors: Jacob F. Moskowitz, Ogden H. Hammond, III
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Patent number: 4069408Abstract: According to the method and apparatus of this invention, water is kept away from the arc in underwater arc welding by means of material contained in a water-tight enclosure. The water-tight enclosure is formed by pressing the seal at the bottom of the enclosure against the object to be welded and by closing the opening for the electrode on top of the enclosure by using the fluid nature of a viscous polymer. Gas generated in the enclosure during welding is expelled through check valves located along two longitudinal sides of the enclosure.The enclosure is prepared above the water surface and then delivered to the welding site. No inert gas is needed.Type: GrantFiled: June 7, 1976Date of Patent: January 17, 1978Assignee: Massachusetts Institute of TechnologyInventors: Koichi Masubuchi, Chon-Liang Tsai
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Patent number: 4068214Abstract: An asynchronous logic array capable of directly implementing Petri net specification of digital systems is disclosed. The array can be used in general synthesis of asynchronous digital circuits and systems. The parallel nature of the array gives the realized systems the speed and other characteristics of hard wired circuits even though they are realized from a uniform logic array. The logic array is particularly suited for implementing control circuits and promises to extend the field of microprogramming to asynchronous and parallel computers.Type: GrantFiled: December 16, 1976Date of Patent: January 10, 1978Assignee: Massachusetts Institute of TechnologyInventor: Suhas S. Patil
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Patent number: 4066510Abstract: An assay is disclosed for determining mutagenic damage caused by the administration of a known or suspected mutagen to diploid human lymphoblastoid cell lines. After administration of or exposure to a mutagenic agent, the lymphoblasts are incubated for a sufficient number of generations to allow full expression of phenotypic resistance to 6-thioguanine or other purines which serve as substrates for hypoxanthine guanine phosphoribosyl transferase (HGPRT). A surprising discovery is the remarkably long length of time required for such phenotypic expression. After the phenotypic lag has passed, the mutant fraction can be determined to complete the assay. A nontoxic, active, sterile microsomal drug-metabolizing system compatible with mammalian cell bioassays is also disclosed which can be used in the assay to determine metabolite-caused mutagenesis.Type: GrantFiled: May 24, 1976Date of Patent: January 3, 1978Assignee: Massachusetts Institute of TechnologyInventor: William G. Thilly
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Patent number: 4066821Abstract: Tungsten carbide tools are provided having improved wear properties which tools produce an improved surface finish on workpieces cut with said tools, both initially and after extended use. The tools are prepared by a process which comprises applying a coating of a Group IVB or VB metal of the Periodic Chart of the Elements over the tool, diffusing said metal into the tool and removing any excess of the metal from the surface of the tool, possibly by further diffusion of the metal into the tool. The preferred method is by gaseous decomposition of a metal halide in an atmosphere which does not contain a carbon source such as methane, used in some previous processes. The source of the carbon in the Group IVB or VB metal carbide is the carbon in the carbide tool being coated. Tools formed in accordance with the invention have wear properties such that they typically last at least four times as long as untreated tools and under most preferred conditions, as much as nine times as long as untreated tools.Type: GrantFiled: January 22, 1976Date of Patent: January 3, 1978Assignee: Massachusetts Institute of TechnologyInventors: Nathan Henry Cook, Bruce M. Kramer
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Patent number: 4067037Abstract: A transistor structure capable of high frequency operation with low collector currents is obtained by fabricating the transistor using nitride techniques to minimize the emitter area and base width area beyond that obtainable by conventional masking techniques. The emitter is surrounded on three sides by low capacitance dielectric which reduces its emitter-to-collector capacitance and hence improves high frequency performance.Type: GrantFiled: April 12, 1976Date of Patent: January 3, 1978Assignee: Massachusetts Institute of TechnologyInventor: Paul Greiff
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Patent number: 4063105Abstract: Schemes for generating tunable coherent radiation by noncollinear phase-matched sum-difference frequency optical mixing in a nonlinear medium for use, by way of illustration, in connection with uranium 235-isotope separation in UF.sub.6.Type: GrantFiled: June 24, 1976Date of Patent: December 13, 1977Assignee: Massachusetts Institute of TechnologyInventors: Roshan L. Aggarwal, Neville K. S. Lee, Benjamin Lax
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Patent number: 4059982Abstract: Appropriate heating and temperature sensing means are immersed in a medium the thermal conductivity, k, and thermal diffusivity, .alpha., of which are to be determined both in the presence of and in the absence of a flow of fluid therethrough. The method and system used for making such measurements operate in accordance with a thermal model of the heating means and the medium wherein the heating means is treated as a distributed thermal mass and wherein heat conduction occurs in a coupled thermal system which comprises both the heating means and the adjacent region of the medium which surrounds such heating means.Type: GrantFiled: August 29, 1975Date of Patent: November 29, 1977Assignee: Massachusetts Institute of TechnologyInventor: Harry Frederick Bowman
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Patent number: 4060754Abstract: An electronic motor that accepts single-phase power and converts the same to polyphase power which is delivered to a polyphase winding of the machine. The electronic motor includes an electronic synthesizer. The synthesizer is shown in the context of an electronic motor, but in a wider context as well.Type: GrantFiled: May 14, 1976Date of Patent: November 29, 1977Assignee: Massachusetts Institute of TechnologyInventors: James L. Kirtley, Jr., Richard H. Baker
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Patent number: 4060081Abstract: A multilayer membrane, which is useful as synthetic skin, is disclosed herein. A first layer is formed from a material which does not provoke an immune response and which is also insoluble and nondegradable in the presence of body fluids and/or body enzymes. Preferred materials for the first layer are crosslinked composites of collagen and a mucopolysaccharide. A second layer is formed from a nontoxic material which controls the moisture flux of the overall membrane to about 0.1 to 1 mg./cm.sup.2 /hr. Suitable materials for the second layer include synthetic polymers such as silicone resins, polyacrylate or polymethacrylate esters or their copolymers, and polyurethanes.Type: GrantFiled: July 15, 1975Date of Patent: November 29, 1977Assignee: Massachusetts Institute of TechnologyInventors: Ioannis V. Yannas, John F. Burke, Philip L. Gordon, Chor Huang
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Patent number: 4059461Abstract: A method is disclosed for improving the crystallinity of semiconductor films by scanning the surface of such films with a shaped, focused laser beam. The laser is matched to the film so that the beam delivers sufficient energy thereto to heat the film above a temperature at which crystallization occurs along the scan track.Type: GrantFiled: December 10, 1975Date of Patent: November 22, 1977Assignee: Massachusetts Institute of TechnologyInventors: John C. C. Fan, Herbert J. Zeiger
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Patent number: 4055758Abstract: A continuously programmable matched filter device using a piezoelectric substrate capable of propagating acoustic wave signals on a selected surface thereof and a semiconductor substrate mounted adjacent and spaced from such surface. Means are provided for altering the conductivity pattern in the semiconductor substrate in accordance with the wave form of a reference wave signal so that a representation of the reference wave is effectively stored therein. Storage of the reference is achieved with electrostatic charge by supplying a plurality of electrons in the spatial region between the substrates or by manipulating the carriers in the semiconductor material into trapping states in order to produce such altered conductivity pattern. A second signal can thereupon be propagated along the piezoelectric substrate to interact with the stored reference conductivity pattern to provide either correlation or convolution operation depending on the direction of propagation thereof along the piezoelectric surface.Type: GrantFiled: March 31, 1976Date of Patent: October 25, 1977Assignee: Massachusetts Institute of TechnologyInventors: Ernest Stern, Richard C. Williamson, Abraham Bers, John H. Cafarella
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Patent number: 4051371Abstract: An intense light source, preferably of high monochromaticity, having its beam modulated at a frequency f.sub.o through a wavelength range including an absorption line of a species to be detected, energizes a chamber containing a sample of the species. The modulation frequency may also be a multiple or sub-multiple of the natural resonant accoustic frequency of the sample chamber. A microphone in the sample chamber provides an output signal proportional to the concentration of the species. The radiation beam is further incident upon a calibration chamber containing a predetermined concentration of the species. A microphone in the calibration chamber provides a calibration signal for comparison with the sample signal to determine the concentration of the species in the sample cell. Means are provided for adjusting the center of the wavelength modulation range so that it bears a known relation to the center of the species absorption line.Type: GrantFiled: April 26, 1976Date of Patent: September 27, 1977Assignee: Massachusetts Institute of TechnologyInventors: C. Forbes Dewey, Jr., Lon O. Hocker
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Patent number: 4051462Abstract: A memory system is shown in which communication to and from memory cells is effected by optical beams. Memory cells are shown employing elements with negative resistance and operating in either of two stable modes. Other memory cells are shown employing subharmonic oscillators operating in either of two phase relationships. The memory cells and systems permit extremely fast operation.Type: GrantFiled: July 16, 1975Date of Patent: September 27, 1977Assignee: Massachusetts Institute of TechnologyInventors: Ali Javan, Charles F. Davis, Jr.
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Patent number: RE29578Abstract: Tunneling electronic devices responsive to infrared and far infrared radiation are formed by overlapping deposits which define ultra-thin dielectric layers (less than aout 10 Angstrom thickness) between metal layers, and contact areas of the order of 1 micron.sup.2 or less. Preferred embodiments feature operation in the negative impedance region, particularly using multibarrier structures or operating at low temperature with both metals superconductors, and incorporation of the same in oscillators and multivibrators. Other embodiments feature two or more such devices in the form of triodes having positive feedback achieved by radiative or inductive coupling using integrally deposited line structures as the respective antennas or inductors. Similar deposited antennas, e.g. dipole antennas, are employed to produce radiative outputs from the devices achieving, e.g. tunable sources of radiation in the far infrared or infrared.Type: GrantFiled: May 9, 1977Date of Patent: March 14, 1978Assignee: Massachusetts Institute of TechnologyInventor: Ali Javan