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Full-Text Articles in Chemical Engineering

Ultra High Density Storage Media And Method Thereof, Ravi F. Saraf Jan 2000

Ultra High Density Storage Media And Method Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A storage media for storing information having a substrate. The substrate has an upper surface and a molecular weight greater than 5,000. Preferably the material is a polymer. The material has a plurality of piles of molecular chains in selected areas formed by pushing the molecular chains of the material on its upper surface to the selected area mechanically with a mechanical tool. The piles represent written information. The mechanical tool is preferably an atomic force microscope. Another aspect of the present invention is a method for storing information having the steps of selecting a material substrate having an upper …


Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf Jan 2000

Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substituted and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. Compositions of the present invention are useful as corrosion protecting layers for metal substrates, for electrostatic discharge protection, electromagnetic interference shielding, and as …


Process For Producing Biodiesel Fuel With Reduced Viscosity And A Cloud Point Below Thirty-Two (32) Degrees Fahrenheit, Hossein Noureddini Jan 2000

Process For Producing Biodiesel Fuel With Reduced Viscosity And A Cloud Point Below Thirty-Two (32) Degrees Fahrenheit, Hossein Noureddini

Department of Chemical and Biomolecular Engineering: Patents

Triglycerides are reacted in a liquid phase reaction with methanol and a homogeneous basic catalyst. The reaction yields a spatially separated two phase result with an upper located non-polar phase consisting principally of non-polar methyl esters and a lower located phase consisting principally of glycerol and residual methyl esters. The glycerol phase is passed through a strong cationic ion exchanger to remove anions, resulting in a neutral product which is flashed to remove methanol and which is reacted with isobutylene in the presence of a strong acid catalyst to produce glycerol ethers. The glycerol ethers are then added back to …


Electrode Modification Using An Unzippable Polymer Paste, Ravi F. Saraf Jan 2000

Electrode Modification Using An Unzippable Polymer Paste, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A paste is described for capping electrodes with an oxide free metal layer incorporating a solvent, an unzippable polymer and particles. The electrode could be an interconnect such as a C4 bump. A method for forming a coating and for testing integrated circuit chips is also described. The invention overcomes the problem of interconnecting Pb containing electrodes that are covered with an insulating oxide on integrated circuit chips by coating the Pb containing electrode with Au to provide an oxide free surface for testing and interconnection.


Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf Dec 1999

Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electronic device that is equipped with a plurality of bonding pads positioned on the device for making electrical interconnections and electrically conductive composite bumps adhered to the bonding pads wherein the bumps are formed of a composite material consisting of a thermoplastic polymer and at least about 30 volume percent of conductive metal particles based on the total volume of the metal particles and the thermoplastic polymer. The present invention is also directed to a method of making electrical interconnections to an electronic device by pressing a plurality of composite bumps of a polymeric based material against a substrate …


Method For Providing Discharge Protection Or Shielding, Ravi F. Saraf Dec 1999

Method For Providing Discharge Protection Or Shielding, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

Electrostatic discharge protection or electromagnetic interference shielding is provided by applying a composition comprising a thermoset or thermoplastic polymeric matrix, and a conductive filler component, where said filler component comprises electrically conductive particles and at least one conducting polymer to a dielectric substrate.


Inside-Out Crosslinked And Commercial-Scale Hydrogels, And Sub-Macromolecular Selective Purification Using The Hyrdogels, William H. Velander, Kevin E. Van Cott Nov 1999

Inside-Out Crosslinked And Commercial-Scale Hydrogels, And Sub-Macromolecular Selective Purification Using The Hyrdogels, William H. Velander, Kevin E. Van Cott

Department of Chemical and Biomolecular Engineering: Patents

Relating to chromatographic processes and ion-exchange and affinity matrices, a spatial installation method for a bifunctional reagent that crosslinks and/or activates a polymer matrix is disclosed, with inside-outside installation of a bifunctional reagent on and within a polymer matrix. The polymer matrix is cellulose, agarose, or chitosan particles. The installation may be followed by inside-outside ligand attachment, by further reacting the matrix with a ligand or ionic group so that a higher concentration of ligand or ionic moiety occurs on the intra-particle volume than the outer matrix surface.


Methods Of Fabricating Plasticized, Antiplasticized And Crystalline Conducting Polymers And Precursors Thereof, Ravi F. Saraf Oct 1999

Methods Of Fabricating Plasticized, Antiplasticized And Crystalline Conducting Polymers And Precursors Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

Methods of forming materials containing precursors to electrically conductive polymers and electrically conductive polymers are described which have a high degree of crystallinity. The high degree of crystallinity is achieved by preparing the materials under conditions which provide a high degree of mobility to the polymer molecules permitting them to associate with one another to form a crystalline state. High levels of electrical conductivity are achieved in in the electrically conductive materials without stretch orienting the material. The enhanced electrical conductivity is isotropic as compared to a stretch oriented film which has isotropic electrical conductivity. In the preferred embodiment, additives …


Organic-Metallic Composite Coating For Copper Surface Protection, Ravi F. Saraf Sep 1999

Organic-Metallic Composite Coating For Copper Surface Protection, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

Copper-containing surfaces of substrates such as laminated electronic circuit boards are protected by organometallic coatings comprising organic compounds selected from the group consisting of benzimidazoles, alkylimidazoles, benzotriazozles and alkyltriazoles, substituted or unsubstituted, and metal particles of solder-wettable metals or metal solders. The metal particles can be thermally formed in situ from metallic compounds such as noble metal acetates, acetylacetonates and carbonates.


Polycrystalline Conducting Polymers And Precursors Thereof Having Adjustable Morphology And Physical Properties, Ravi F. Saraf Aug 1999

Polycrystalline Conducting Polymers And Precursors Thereof Having Adjustable Morphology And Physical Properties, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

Polycrystalline materials containing crystallies of precursors to electrically conductive polymers and electrically conductive polymers are described which have an adjustable high degree of crystallinity. The intersticial regions between the crystallites contains amorphous material containing precursors to electrically conductive polymers and/or electrically conductive polymers. The degree of crystallinity is achieved by preparing the materials under conditions which provide a high degree of mobility to the polymer molecules permitting them to associate with one another to form a crystalline state. This is preferable achieved by including additives, such as plasticizers and diluents, to the solution from which the polycrystalline material is formed. …


Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander May 1999

Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

A method is disclosed for coupling a ligand within a porous support. The method involves mixing ligand and porous support under conditions sufficient to suppress coupling conditions of the ligand to the porous support while enhancing the relative rate of diffusion, to the rate of reaction, of the ligand into and within the porous support, and then altering the conditions to enhance rapid coupling of the ligand within the porous support. The alteration from diffusion conditions to coupling conditions involves a change in the reaction solution of pH, ionic strength, temperature, coupling competitor, such that a relatively lower Thiele Modulus …


Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander, Anuradha Subramanian May 1999

Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander, Anuradha Subramanian

Department of Chemical and Biomolecular Engineering: Patents

A method is disclosed for coupling a ligand within a porous support. The method involves mixing ligand and porous support under conditions sufficient to suppress coupling conditions of the ligand to the porous support while enhancing the relative rate of diffusion, to the rate of reaction, of the ligand into and within the porous support, and then altering the conditions to enhance rapid coupling of the ligand within the porous support. The alteration from diffusion conditions to coupling conditions involves a change in the reaction solution of pH, ionic strength, temperature, coupling competitor, such that a relatively lower Thiele Modulus …


Direct Chip Attach For Low Alpha Emission Interconnect System, Ravi F. Saraf Apr 1999

Direct Chip Attach For Low Alpha Emission Interconnect System, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An interconnect system that has low alpha particle emission characteristics for use in an electronic device includes a semiconductor chip that has an upper surface and spaced apart electrically resistive bumps positioned on conductive regions of the upper surface, the electrically resistive bumps are made of a composite material of a polymer and metal particles, and a substrate that has conductive regions bonded to the electrically resistive bumps in a bonding process wherein the electrically resistive bumps convert to electrically conductive bumps after the bonding process.


Transgenic Mammals Expressing Human Coagulation Factor Viii , William H. Velander Mar 1999

Transgenic Mammals Expressing Human Coagulation Factor Viii , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

A non-human transgenic mammalian animal, as described above, contains an exogenous double stranded DNA sequence stably integrated into the genome of the animal, which comprises cis-acting regulatory units operably linked to a DNA sequence encoding human Factor VIII protein and a signal peptide, where the cis-acting regulatory units are active in mammary gland cells and the signal peptide is active in directing newly expressed Factor VIII into the milk of the animal. The promoter may be a milk protein promoter such as for whey acidic protein, casein, lactalbumin, or beta-lactoglobulin promoter. The transgenic mammals are preferably farm animals, for example, …


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf Dec 1998

Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electronic device that is equipped with a plurality of bonding pads positioned on the device for making electrical interconnections and electrically conductive composite bumps adhered to the bonding pads wherein the bumps are formed of a composite material consisting of a thermoplastic polymer and at least about 30 volume percent of conductive metal particles based on the total volume of the metal particles and the thermoplastic polymer. The present invention is also directed to a method of making electrical interconnections to an electronic device by pressing a plurality of composite bumps of a polymeric based material against a substrate …


Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf Jul 1998

Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substituted and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. The compositions of the present invention are useful as adhesives for interconnecting a semiconductor chip to a substrate


Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf Jul 1998

Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substituted and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. The compositions of the present invention are useful as adhesives for interconnecting a semiconductor chip to a substrate


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf Dec 1997

Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substiututed and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. Compositions of the present invention are useful as corrosion protecting layers for metal substrates, for electrostatic discharge protection, electromagnetic interference shielding, and as …


Expression Of Human Protein C In Mammary Tissue Of Transgenic Mammals , William H. Velander Dec 1996

Expression Of Human Protein C In Mammary Tissue Of Transgenic Mammals , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

Recombinant protein C characterized by a high percentage of active protein can be obtained in the milk of transgenic mammals that incorporate DNAs according to the present invention. Transgenic mammals of the present invention are produced by introducing into developing embryos DNA that encodes protein C, such that the DNA is stably incorporated in the DNA of germ line cells of the mature mammals and inherited in normal, mendelian fashion.


Fabrication Of Double Side Fully Metallized Plated Thru-Holes, In Polymer Structures, Without Seeding Or Photoprocess, Ravi F. Saraf Aug 1996

Fabrication Of Double Side Fully Metallized Plated Thru-Holes, In Polymer Structures, Without Seeding Or Photoprocess, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

The present invention is directed to a process of a method for the full metallization of thru-holes in a polymer structure comprising the steps of applying a film-forming amount of a conductive polymer-metal composite paste to a metal cathode; bonding a patterned polymer structure to said paste; subjecting said polymer structure to an electrolytic plating bath for a time sufficient to fully metallize thru-hole surfaces in said patterned polymer structure and removing the structure from the cathode assembly. The fully metallized thru-hole polymer structure can then be cleaned and polished to produce a finished product.


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf Aug 1996

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Sulfur Tolerant Bimetallic Zeolitic Reforming Catalysts, Gustavo F. Larsen Jul 1996

Sulfur Tolerant Bimetallic Zeolitic Reforming Catalysts, Gustavo F. Larsen

Department of Chemical and Biomolecular Engineering: Patents

New compositions of matter comprise a metal from the group consisting of platinum, rhodium and palladium, a metal from the first row of Group VIII of the Periodic Table and a nonacidic L-zeolite. A preferred composition is Pt--Ni/KL-zeolite. Such catalysts are prepared by coimpregnation of the zeolite with the metals. Methods of using the catalysts in reforming, aromatization or dehydrogenation are provided.


Polyelectrolyte Dna Conjugation And Genetic Transformation Of An Animal , William H. Velander Jun 1996

Polyelectrolyte Dna Conjugation And Genetic Transformation Of An Animal , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

Improved cellulosic beads for use as supports in bioaffinity chromatography are produced by dissolution of cellulose in a chaotropic cellulose solvent, formation of the dissolved cellulose into droplets, and immersion of the droplets into a non-solvent capable of solvent interchange with the cellulose solvent to form generally spherical porous cellulose beads of narrow particle size distribution. The beads formed are preferably made with cellulose having a degree of polymerization between 100 and 200, and the resulting beads when saturated with water without drying contain between 1% and 7% cellulose by weight and have a particle size of at least about …


Lignocellulosic And Cellulosic Beads For Affinity And Immunoaffinity Chromatography Of High Molecular Weight Protiens, William H. Velander Jul 1994

Lignocellulosic And Cellulosic Beads For Affinity And Immunoaffinity Chromatography Of High Molecular Weight Protiens, William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

Improved cellulosic beads for use as supports in bioaffinity chromatography are produced by dissolution of cellulose in a chaotropic cellulose solvent, formation of the dissolved cellulose into droplets, and immersion of the droplets into a non-solvent capable of solvent interchange with the cellulose solvent to form generally spherical porous cellulose beads of narrow particle size distribution. The beads formed are preferably made with cellulose having a degree of polymerization between 100 and 200, and the resulting beads when saturated with water without drying contain between 1% and 7% cellulose by weight and have a particle size of at least about …