Patents Represented by Attorney, Agent or Law Firm Jayadeep R. Deshmukh
  • Patent number: 6638412
    Abstract: A method of inhibiting dissolution of a transition metal alloy anode (40) of an aluminium electrowinning cell comprises providing a sodium-inert layer (11,20,50,50′) on a sodium-active cathodic cell material (15), such as carbon, and electrolysing alumina dissolved in a sodium ion-containing molten electrolyte (30). Aluminium ions rather than sodium ions are cathodically reduced on the sodium-inert layer to inhibit the presence in the molten electrolyte (30) of soluble cathodically-produced sodium metal that constitutes an agent for chemically reducing the anode's transition metal oxides and anodically evolved oxygen, thereby inhibiting reduction of the anode's transition metal oxides by sodium metal and maintaining the evolved oxygen at the anode at a concentration such as to produce at the alloy/oxide layer interface stable and coherent transition metal oxides having a high level of oxidation.
    Type: Grant
    Filed: March 30, 2002
    Date of Patent: October 28, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio De Nora, Jean-Jacques Duruz
  • Patent number: 6607657
    Abstract: Carbon-containing components of cells for the production of aluminium by the electrolysis of alumina dissolved in a cryolite-based molten electrolyte are protected from attack by liquid and/or gaseous components of the electrolyte in the form of elements, ions or compounds, by a refractory boride coating applied from a slurry composed of pre-formed particulate refractory boride in a colloidal carrier which is dried and heated to consolidate the coating.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: August 19, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jainagesh A. Sekhar
  • Patent number: 6602999
    Abstract: A novel process for the production of an improved amorphous form of cefpodoxime proxetil [(6R-[6&agr;,7&bgr;(Z))]-7-{E(2-Amino-4-thiazolyl)(methoxyimino)acetyl]amino]-3-(methoxymethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-1-[[(1-methylethoxy)carboxylic acid-1-[[(1-methylethoxy)carbonyl]oxy]ethyl ester, is described.
    Type: Grant
    Filed: May 21, 2002
    Date of Patent: August 5, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Yatendra Kumar, Rakesh Kumar Arora, Kaptan Singh
  • Patent number: 6590085
    Abstract: This invention relates generally to compounds and processes for synthesizing derivatives of 2-3-O-isopropylidene-&agr;-L-xylo-2-hexulofuranosonic acid. The compounds of this invention are useful, inter-alia, for the inhibition and prevention of cell adhesion and cell adhesion-mediated pathologies, including inflammatory and autoimmune diseases, such as bronchial asthma, rheumatoid arthritis, type I diabetes, multiple sclerosis, allograft rejection and psoriasis. This invention also relates to pharmacological compositions containing derivatives of 2-3-O-isopropylidene-&agr;-L-xylo-2-hexulofuranosonic acid and the methods of treating such pathologies as listed above.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: July 8, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Sudershan K Arora, Nawal Kishore, Jang Bahadur Gupta, Vishwas D Joshi
  • Patent number: 6586005
    Abstract: A sustained release formulation of etodolac for once daily administration is described.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: July 1, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Rajeev S. Raghuvanshi, Ashok Rampal, Himadri Sen
  • Patent number: 6565877
    Abstract: A taste masked composition which comprises a bitter tasting drug, a combination of two enteric polymers comprising, a methacrylic acid copolymer and a phthalate polymer is described. The composition of the present invention is prepared by dissolving the active ingredient, the methacrylic acid copolymer and the phthalate polymer in a solvent and recovering the composition from the solution thereof.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: May 20, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Gour Mukherji, Sandhya Goel, Vinod Kumar Arora
  • Patent number: 6562224
    Abstract: A method of manufacturing an anode for use in a cell for the electrowinning of aluminium comprises oxidising before cell operation an iron-nickel alloy substrate in an oxygen-containing atmosphere, such as air, at a temperature which is at least 50° C., preferably 100° C., above the operating temperature of the cell to form on the surface of the iron-nickel substrate a coherent and adherent iron oxide-containing outer layer, in particular a hematite-containing layer having a limited ionic conductivity for oxygen ions and acting as a partial barrier to monoatomic oxygen. The outer layer is electrochemically active for the oxidation of oxygen ions and reduces also diffusion of oxygen to the iron-nickel alloy substrate when the anode is in use.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: May 13, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Olivier Crottaz, Jean-Jacques Duruz
  • Patent number: 6559187
    Abstract: The present invention is directed to a liquid formulation of metformin or its pharmaceutically acceptable salts thereof. The liquid pharmaceutical composition comprises a therapeutically effective amount of metformin or its pharmaceutically acceptable salt, in a liquid carrier, which may also include a sweetener that does not increase the blood glucose level of a subject after ingestion thereof. In one embodiment, it may also include alkyl hydroxyethylcellulose, and/or a polyhydroxy alcohol. In another embodiment, the carrier may contain a sweetener, mineral acid, and bicarbonate salt maintained at a pH of 4.0 to 9.0. It is useful for treating hyperglycemia and diabetes.
    Type: Grant
    Filed: August 7, 2001
    Date of Patent: May 6, 2003
    Assignee: Ranbaxy Signature LLC
    Inventors: Ravi Chandran, Ashish Gogia
  • Patent number: 6541511
    Abstract: The present invention relates to a novel methyl analog of simvastatin, which has the ability to inhibit the synthesis of cholesterol. The compound of the present invention holds promise for the treatment and prophylaxis of hypercholesterolemia and of various cardiac disorders. The invention also relates to a process for making the novel compound.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: April 1, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Rajesh Kumar Thaper, Saridi Madhava Dileep Kumar, Yatendra Kumar
  • Patent number: 6540887
    Abstract: A cell for the electrowinning of aluminium comprises at least one non-carbon metal-based anode (10) having an electrically conductive metallic structure (12, 13, 15) which is suspended substantially parallel to a facing cathode (20, 21, 22). Such metallic structure (12, 13, 15) comprises a series of parallel horizontal anode members (15), each having an electrochemically active surface (16) on which during electrolysis oxygen is anodically evolved. The electrochemically active surfaces (16) are in a generally coplanar arrangement to form the active anode surface. The anode members are spaced apart from one another by inter-member gaps forming flow-through openings (17) for the circulation of electrolyte (30) driven by the escape of anodically-evolved oxygen. The electrolyte (30) may circulate upwardly and/or downwardly in the flow-through openings (17) and possibly around the anode structure (12, 13, 15).
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: April 1, 2003
    Assignee: Moltech Invent SA
    Inventor: Vittorio de Nora
  • Patent number: 6534494
    Abstract: A process for preparing cefuroxime axetil in substantially amorphous form comprises forming a mixture of crystalline cefuroxime axetil and at least one pharmaceutically acceptable excipient, and subjecting the mixture to milling for a period of time sufficient to convert the crystalline cefuroxime axetil to substantially amorphous form, i.e., the crystallinity is less than 5%. The amorphous cefuroxime axetil has a chemical purity of at least 95%. Desirably, the particles of the milled material are reduced to a size of less than 2.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: March 18, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Jitendra Krishan Somani, Sanjeev Sethi, Om Dutt Tyagi
  • Patent number: 6533909
    Abstract: A bipolar cell for the electrowinning of aluminium has bipolar electrodes each comprising a carbon cathode body having on one side an active surface on which aluminium is produced and connected on the other side through an oxygen impermeable barrier layer to an electrochemically active anode layer having an oxygen evolving iron oxide-based outer surface. The anode layer may comprise a metal-based anode substrate and a transition metal oxide-based outside layer, in particular an iron oxide-based outside layer, which either is an applied layer or is obtainable by oxidising the surface of the anode substrate which contains iron. During operation, the anode layer can be kept dimensionally stable by maintaining in the electrolyte a concentration of transition metal species which are present as one or more corresponding transition metal oxides in the electrochemically-active layer.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: March 18, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora
  • Patent number: 6528660
    Abstract: A process for the preparation of amorphous atorvastatin calcium and hydrates thereof which comprises: (a) dissolving crystalline atorvastatin calcium in a non-hydroxylic solvent; (b) adding a non-polar hydrocarbon anti-solvent or adding the dissolved atorvastatin to the non-polar anti-solvent to precipitate out atorvastatin calcium; and (c) removing the solvent by filtration to afford amorphous atorvastatin calcium.
    Type: Grant
    Filed: February 12, 2002
    Date of Patent: March 4, 2003
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Yatendra Kumar, Rajesh Kumar Thaper, S. M. Dileep Kumar
  • Patent number: 6521115
    Abstract: An anode of a cell for the electrowinning of aluminium comprises an iron-nickel alloy body or layer whose surface is oxidised to form a coherent and adherent outer iron oxide-based layer, in particular hematite, the surface of which is electrochemically active for the oxidation of oxygen ions and which reduces diffusion of oxygen from the electrochemically active surface into the iron-nickel alloy body or layer. The anode may be kept dimensionally stable during cell operation by maintaining a sufficient amount of dissolved alumina and iron species in the electrolyte to prevent dissolution of the outer oxide layer of the or each anode and by reducing the electrolyte operating temperature to limit dissolution of iron and by reducing the electrolyte operating temperature to limit dissolution of iron species in the electrolyte.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: February 18, 2003
    Assignee: Moltech Invent S. A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora, Olivier Crottaz
  • Patent number: 6521116
    Abstract: A cell for the electrowinning of aluminium comprising one or more anodes (10), each having a metal-based anode substrate, for instance comprising a metal core (11) covered with an metal layer 12, an oxygen barrier layer (13), one or more intermediate layers (14; 14A, 14B) and an iron layer (15). The anode substrate is covered with an electrochemically active transition metal oxide layer, in particular an iron oxide-based outside layer (16) such as a hematite-based layer, which remains dimensionally stable during operation in a cell by maintaining in the electrolyte a sufficient concentration of iron species and dissolved alumina. The cell operating temperature is sufficiently low so species and dissolved alumina.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: February 18, 2003
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora, Olivier Crottaz
  • Patent number: 6455097
    Abstract: A method of applying a treating liquid to a porous body (11), in particular a pre-baked carbon component of an aluminium production cell, such as an anode block, a cathode block or a sidewall. In this method first the body (11) to be treated is inserted, with its part to be treated facing up, in the treating chamber (12). At least one sealing member (13) is then applied to the body so as to isolate a space (14) in an upper part of the treating chamber (12) around the part of the body to be treated from a lower part (15) of the treating chamber around a bottom part of the body which is not to be treated. Next, treating liquid (10) is supplied to the upper part (14) of the treating chamber to cover the part of the body to be treated with the treating liquid and applying a vacuum to intake an amount of the treating liquid into pores in the part of the body to be treated. Then the body (11) is freed from the sealing member(s) (13), and removed from the treating chamber (12).
    Type: Grant
    Filed: September 16, 2000
    Date of Patent: September 24, 2002
    Assignee: Moltech Invent S.A.
    Inventors: Georges Berclaz, Gaynor Johnston, Vittorio de Nora
  • Patent number: 6455107
    Abstract: A body of carbonaceous or other material for use in corrosive environments such as oxidising media or gaseous or liquid corrosive agents at elevated temperatures, in particular in molten salts such as cryolite, is coated with a protective surface coating which improves the resistance of the body to oxidation or corrosion and which may also enhance the bodies electrical conductivity and/or its electrochemical activity. The protective coating is applied in one or more layers from a colloidal slurry containing reactant or non-reactant substances, or a mixture of reactant and non-reactant substances, in particular mixtures containing silicon carbide and molybdenum silicide or silicon carbide and silicon nitride, which when the body is heated to a sufficient elevated temperature reaction sinter as a result of micropyretic reaction and/or sinter without reaction to form the protective coating.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: September 24, 2002
    Assignee: Moltech Invent S.A.
    Inventors: Jainagesh A. Sekhar, Vittorio de Nora
  • Patent number: 6441226
    Abstract: The present invention relates to a process for the preparation of 13-cis isomer of Vitamin A acid, commonly known as isotretinoin, in a single step.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: August 27, 2002
    Assignee: Ranbaxy Laboratories Limited
    Inventors: Mohammad Salman, Vijay Kumar Kaul, J. Suresh Babu, Naresh Kumar
  • Patent number: 6436273
    Abstract: An electrolytic cell for the electrowinning of aluminium comprises a cathode cell bottom provided with a series of sloped active cathode surfaces (11, 12) down which produced aluminium (60) is drained, and a series of recessed grooves or channels (20), below the bottom of the cathode active surfaces (11, 12) and extending therealong which collect and evacuate the drained produced aluminum (63). Preferably the active surfaces (11, 12) are V-shaped and the recessed grooves or channels (20) are provided with a sloping bottom and a constant cross-sectional area. Alumina is so fed into the cell as to supply alumina-rich electrolyte (62) into the recessed grooves or channels (20) which contain the alumina-rich electrolyte along substantially their entire length above the drained layer of aluminium (63).
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: August 20, 2002
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 6436274
    Abstract: A non-carbon, metal-based slow-consumable anode of a cell for the electrowinning of aluminium self-forms during normal electrolysis an electrochemically-active oxide-based surface layer (20). The rate of formation (35) of the layer (20) is substantially equal to its rate of dissolution (30) at the surface layer/electrolyte interface (25) thereby maintaining its thickness substantially constant, forming a limited barrier controlling the oxidation rate (35). The anode (10) usually comprises an alloy of iron with at least one of nickel, copper, cobalt or zinc which during use forms an oxide surface layer (20) mainly containing ferrite.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: August 20, 2002
    Inventors: Vittorio De Nora, Jean-Jacques Duruz