Patents Assigned to TDA Research
  • Patent number: 6289889
    Abstract: Improved heaters and self-heating packages that function without application of external energy. Heat is generated by contact of a heat-producing composition, such as calcium oxide, and an activating solution which is typically water. The heater contains multi-compartments containing heat-producing composition and activating solution. The heater is activated by application of hand pressure to rupture a frangible seal which allows the heater components to mix. The heater compartments are at least in part formed from flexible walls. The self-heating package has one or more products or product containers in thermal contact with one or more heaters. In preferred packaging embodiments, the heating package has one or more product containers or pouches in thermal contact with one or more heaters. In a specific embodiment, the product container is integrally formed with the heater. Preferred self-heating packages are constructed entirely of flexible packaging materials.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: September 18, 2001
    Assignee: TDA Research, Inc.
    Inventors: William L. Bell, James L. Dippo
  • Patent number: 6248257
    Abstract: A portable heat source that may be used to warm food, beverage or other supplies. The heater contains a heat-producing composition that is a solid that may be stored for long periods of time, and activated by addition of water or an aqueous solution. Heat-producing compositions contain an acidic anhydride, an acidic salt, a basic anhydride or a basic salt. Preferred heat-producing compositions contain a mixture of an acidic anhydride or salt together with a basic anhydride or salt, such that addition of water to both acidic and basic anhydrides produces heat as well as acid and base respectively; subsequent reaction of the acid and base produces additional heat, as well as a safe, neutral product that is easily disposed. The invention further consists of means and methods for regulating the rate of heat production in heaters by the addition of inert additives to heat-producing compositions and the application of processing methods that regulate access of water to heat-producing compounds.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: June 19, 2001
    Assignee: TDA Research, Inc.
    Inventors: William L. Bell, Robert J. Copeland, Jianhan Yu, James L. Dippo
  • Patent number: 6207130
    Abstract: A method has been developed for the solution-based metal exchange of carboxylato-alumoxanes [Al(O)x(OH)y(O2CR)z]n with a wide range of metal cations. Metal-exchanged carboxylato-alumoxanes are new, particularly those in which about 10% to about 50% or more of the Al ions are exchanged for other metal ions. Additionally, the carboxylic acid ligands can be stripped from the boehmite core of metal-exchanged carboxylato-alumoxanes at low temperature leading to the formation of metal-exchanged boebmite particles. These new material phases can be used as intermediates for preparation of mixed metal aluminum oxide materials. Thermolysis of the metal-exchanged carboxylato-alumoxanes or metal-exchanged boehmite particles results in doped aluminas (M/Al2O3), binary (MAlOx), ternary (MM′AlOx) and even more complex metal aluminum oxide compounds, where M and M′ are metal ions other than those of aluminum and are preferably those of Lanthanide metals or transition metals.
    Type: Grant
    Filed: April 10, 1998
    Date of Patent: March 27, 2001
    Assignees: Rice University, TDA Research, Inc.
    Inventors: Aivaras Kareiva, Chuansheng Bai, Charles Jeffrey Harlan, D. Brent MacQueen, Andrew R. Barron, Ronald L. Cook
  • Patent number: 6099819
    Abstract: This invention provides catalysts for the oxidation of hydrogen sulfide. In particular, the invention provides catalysts for the partial oxidation of hydrogen sulfide to elemental sulfur and water. The catalytically active component of the catalyst comprises a mixture of metal oxides containing titanium oxide and one or more metal oxides which can be selected from the group of metal oxides or mixtures of metal oxides of transition metals or lanthanide metals. Preferred metal oxides for combination with TiO.sub.2 in the catalysts of this invention include oxides of V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Tc, Ru, Rh, Hf, Ta, W, Au, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Catalysts which comprise a homogeneous mixture of titanium oxide and niobium (Nb) oxide are also provided. A preferred method for preparing the precursor homogenous mixture of metal hydroxides is by coprecipitation of titanium hydroxide with one or more other selected metal hydroxides.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: August 8, 2000
    Assignee: TDA Research, Inc.
    Inventors: Girish Srinivas, Chuansheng Bai
  • Patent number: 5935486
    Abstract: This invention is a portable heat source that may be used to warm food, beverage or other supplies. The heater material is a solid that may be stored for long periods of time, and activated by addition of water or an aqueous solution. The heater consists of an acidic anhydride or salt together with a basic anhydride or salt, such that addition of water to both acidic and basic anhydrides produces heat as well as acid and base respectively; subsequent reaction of the acid and base produces additional heat, as well as a safe, neutral product that is easily disposed. The invention further consists of means to regulate the rate of heat production by the use of additives and processing methods, so that heat is produced at a rate compatible with the rate at which the food or other materials can absorb the heat. The invention further consists of devices incorporating the materials to be heated in an advantageous arrangement with the heater composition.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: August 10, 1999
    Assignee: TDA Research, Inc.
    Inventors: William L. Bell, Robert J. Copeland, Jianhan Yu
  • Patent number: 5271907
    Abstract: A system for high temperature desulfurization of coal-derived gases using regenerable sorbents. One sorbent is stannic oxide (tin oxide, SnO.sub.2), the other sorbent is a metal oxide or mixed metal oxide such as zinc ferrite (ZnFe.sub.2 O.sub.4). Certain otherwise undesirable by-products, including hydrogen sulfide (H.sub.2 S) and sulfur dioxide (SO.sub.2) are reused by the system, and elemental sulfur is produced in the regeneration reaction. A system for refabricating the sorbent pellets is also described.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: December 21, 1993
    Assignee: TDA Research, Inc.
    Inventor: Robert J. Copeland