Patents Represented by Attorney Arthur A. Smith, Jr.
  • Patent number: 4080264
    Abstract: 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: Grant
    Filed: March 1, 1976
    Date of Patent: March 21, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Richard J. Cohen, George B. Benedek
  • Patent number: 4076866
    Abstract: 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: Grant
    Filed: April 30, 1975
    Date of Patent: February 28, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Nicolaos S. Platakis, Harry C. Gatos
  • Patent number: 4075846
    Abstract: 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: Grant
    Filed: May 4, 1976
    Date of Patent: February 28, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: Yao Tzu Li
  • Patent number: 4076916
    Abstract: 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: Grant
    Filed: November 3, 1975
    Date of Patent: February 28, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: Richard J. Lagow
  • Patent number: 4075706
    Abstract: 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: Grant
    Filed: March 31, 1976
    Date of Patent: February 21, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Ernest Stern, Richard C. Williamson, Henry I. Smith
  • Patent number: 4069732
    Abstract: 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: Grant
    Filed: September 8, 1975
    Date of Patent: January 24, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Jacob F. Moskowitz, Ogden H. Hammond, III
  • Patent number: 4069408
    Abstract: 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: Grant
    Filed: June 7, 1976
    Date of Patent: January 17, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Koichi Masubuchi, Chon-Liang Tsai
  • Patent number: 4068214
    Abstract: 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: Grant
    Filed: December 16, 1976
    Date of Patent: January 10, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: Suhas S. Patil
  • Patent number: 4066510
    Abstract: 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: Grant
    Filed: May 24, 1976
    Date of Patent: January 3, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: William G. Thilly
  • Patent number: 4066821
    Abstract: 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: Grant
    Filed: January 22, 1976
    Date of Patent: January 3, 1978
    Assignee: Massachusetts Institute of Technology
    Inventors: Nathan Henry Cook, Bruce M. Kramer
  • Patent number: 4067037
    Abstract: 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: Grant
    Filed: April 12, 1976
    Date of Patent: January 3, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: Paul Greiff
  • Patent number: 4063105
    Abstract: 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: Grant
    Filed: June 24, 1976
    Date of Patent: December 13, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: Roshan L. Aggarwal, Neville K. S. Lee, Benjamin Lax
  • Patent number: 4059982
    Abstract: 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: Grant
    Filed: August 29, 1975
    Date of Patent: November 29, 1977
    Assignee: Massachusetts Institute of Technology
    Inventor: Harry Frederick Bowman
  • Patent number: 4060754
    Abstract: 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: Grant
    Filed: May 14, 1976
    Date of Patent: November 29, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: James L. Kirtley, Jr., Richard H. Baker
  • Patent number: 4060081
    Abstract: 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: Grant
    Filed: July 15, 1975
    Date of Patent: November 29, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: Ioannis V. Yannas, John F. Burke, Philip L. Gordon, Chor Huang
  • Patent number: 4059461
    Abstract: 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: Grant
    Filed: December 10, 1975
    Date of Patent: November 22, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: John C. C. Fan, Herbert J. Zeiger
  • Patent number: 4055758
    Abstract: 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: Grant
    Filed: March 31, 1976
    Date of Patent: October 25, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: Ernest Stern, Richard C. Williamson, Abraham Bers, John H. Cafarella
  • Patent number: 4051371
    Abstract: 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: Grant
    Filed: April 26, 1976
    Date of Patent: September 27, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: C. Forbes Dewey, Jr., Lon O. Hocker
  • Patent number: 4051462
    Abstract: 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: Grant
    Filed: July 16, 1975
    Date of Patent: September 27, 1977
    Assignee: Massachusetts Institute of Technology
    Inventors: Ali Javan, Charles F. Davis, Jr.
  • Patent number: RE29578
    Abstract: 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: Grant
    Filed: May 9, 1977
    Date of Patent: March 14, 1978
    Assignee: Massachusetts Institute of Technology
    Inventor: Ali Javan