Abstract: System and methods for determining a concentration of urea in an aqueous solution disposed in a container are provided. The system includes an infrared light source and an infrared light detector. The system further includes a window disposed proximate to an aperture of the container, such that the infrared light at a first light intensity level from the infrared light source passes through a first portion of the window toward the aqueous solution. A portion of the infrared light is absorbed by the aqueous solution, and a second portion of the infrared light is reflected from the aqueous solution and through a second portion of the window. The infrared light detector system generates a first signal indicative of a second light intensity level based on the second portion of infrared light. The system further includes a microprocessor that determines the second light intensity level based on the first signal, and further determines a urea concentration based on the first and second light intensity levels.

Abstract: A metal alloy which when oxidized forms a highly conductive surface oxide layer. Alloy compositions such as, but not limited to, Ti—Nb, Ti—Ta, La—Sr—Cr, and La—Sr—Co are known to form oxide passivation layers which are highly conductive. Such alloys are useful in electrical contact apparatus. An electrical contact element formed of the alloy has a contact surface which when oxidized forms a highly conductive surface layer, thus maintaining electrical conductivity and continuity through the element. The oxide layer may be formed in situ after assembly of the electrical contact or may be provided in an oxidative step during manufacture. The electrical contact may be formed entirely of one or more of such alloys; or may be formed of an inexpensive substrate base metal, such as steel, having one or more of the alloys coated thereupon; or may be formed of a mixture of the base metal and the alloy.

Abstract: Systems and methods for determining a concentration of biodiesel in a mixture of biodiesel and petrodiesel are provided. In one exemplary embodiment, a method includes receiving an oscillatory signal at an inductance-capacitance-resistance circuit. The circuit has a sensing element fluidly communicating with the mixture of biodiesel and petrodiesel. The method further includes generating a resonant current at a resonant frequency utilizing the circuit in response to the oscillatory signal. The method further includes determining a concentration value indicating the concentration of the biodiesel in the mixture based on an amplitude of the resonant current and/or the resonant frequency, utilizing a microprocessor. The method further includes storing the concentration value in a memory device, utilizing the microprocessor.

Abstract: Systems and methods for determining a total acid number associated with biodiesel in a mixture of biodiesel and petrodiesel are provided. The method includes receiving an oscillatory signal at an inductance-capacitance-resistance circuit. The circuit has a sensing element fluidly communicating with the mixture of biodiesel and petrodiese. The method further includes generating a resonant current at a resonant frequency utilizing the circuit in response to the oscillatory signal. The method further includes determining a dielectric constant value indicating a dielectric constant associated with the biodiesel in the mixture based on the resonant frequency of the resonant current, utilizing a microprocessor. The method further includes determining a concentration value indicating a concentration of the biodiesel in the mixture based on an amplitude of the resonant current and the dielectric constant value, utilizing the microprocessor.

Abstract: A metal alloy which when oxidized forms a highly conductive surface oxide layer. Alloy compositions such as, but not limited to, Ti—Nb, Ti—Ta, La—Sr—Cr, and La—Sr—Co are known to form oxide passivation layers which are highly conductive. Such alloys are useful in electrical contact apparatus. An electrical contact element formed of the alloy has a contact surface which when oxidized forms a highly conductive surface layer, thus maintaining electrical conductivity and continuity through the element. The oxide layer may be formed in situ after assembly of the electrical contact or may be provided in an oxidative step during manufacture. The electrical contact may be formed entirely of one or more of such alloys; or may be formed of an inexpensive substrate base metal, such as steel, having one or more of the alloys coated thereupon; or may be formed of a mixture of the base metal and the alloy.

Abstract: A fuel sensor system for a vehicle includes a fuel pump adapted to be disposed in a fuel tank to pump fuel from the fuel tank to an engine of the vehicle. The fuel sensor system also includes a fuel sensor adapted to be disposed in the fuel tank to measure a property index of the fuel. The fuel sensor system further includes a jet pump connected to the fuel pump to fill the fuel sensor with a fuel sample of the fuel.

Abstract: A fuel sensor system for a vehicle includes a fuel pump adapted to be disposed in a fuel tank to pump fuel from the fuel tank to an engine of the vehicle. The fuel sensor system also includes a fuel sensor adapted to be disposed in the fuel tank to measure a property index of the fuel.

Abstract: The invention generally includes a method of selectively etching a body of silicon material wherein a silicon wafer is used as a working electrode and having an n-type region and a relatively shallow p-type layer. The working electrode and a counterelectrode are placed in a liquid etchant. High voltage pulses, greater than 2 V are applied between the working electrode and the counterelectrode so that holes from the p-type layer are injected into the n-type region and etching is stopped due to oxidation of the n-type region. The technique is useful in producing very thin n-type membranes.

Abstract: Generally, the invention includes a method of wet electrochemical etching of a substrate with an anisotropic etchant using a silver/silver oxide (Ag/Ag.sub.2 O) reference electrode. The silver/silver oxide reference electrode can be used with electrochemical etch-stop techniques to fabricate a variety of semiconductor devices including microsensors and microactuator in a variety of anisotropic etchants. The silver/silver oxide reference electrode eliminates the need to use glass or plastic tubes.

Abstract: Disclosed is an oil sensor system having an oil sensor including two spaced apart electrodes, a triangular waveform means, a comparison means and a signal means. The oil system is used in situ (i.e., used directly in the engine) to determine the presence of two-stroke or four-stroke oil, or the occurrence of an engine malfunction, such as a leakage of antifreeze into the oil.

Abstract: Disclosed is an oil sensor having roughened electrode surfaces to produce oil condition related output current or voltage from the automotive engine oil as it is used.

Abstract: A method of selectively etching a body of a semiconductor material, such as single crystalline silicon, having regions of n-type and p-type conductivity to remove at least a portion of the n-type region. The body is placed in an etching solution of an etchant having a high pH value and a positive voltage is applied between the body and the etchant. This forms passivating layers on the surfaces of the two regions with the passivating layer on the n-type region being different from that on the p-type region. The voltage is then removed and the body is etched for a period long enough to remove all of the passivating layer from the n-type region and at least a portion of the n-type region, but is not long enough to remove all of the passivating layer from the p-type region. This is allowed by the difference between the passivating layers on the two regions. The steps of forming the passivating layers and etching them is repeated until a desired amount of the n-type region is removed.

Abstract: The present invention relates to a method of forming thin bodies of a semiconductor material, such as single crystalline silicon, by selectively etching away a portion of the body until a body of the desired thicknes is obtained. The body includes a p-n junction made up of adjacent regions of p-type and n-type conductivity which are immersed in a chemical etchant with the surface of the p-type region being exposed to the etchant. A time varying voltage waveform having first and second voltage levels is applied through the etchant to the p-n junction. The first voltage level causes a zero forward bias across the p-n junction and the second voltage level causes a reverse bias across the p-n junction. The p-type region is removed by the chemical etchant down to the n-type region.

Abstract: A method of using an electrochemical process in oil-based lubricants to form friction-reducing and wear-reducing molybdenum/iron phosphate films on cast iron surfaces. A cast iron surface acting as the anode means is first coated with a thin film of molybdenum and then bombarded with high energy inert gas ions to form a layer of molybdenum/iron alloy on the surface before the electrochemical process. An electrolytic additive of dialkyl hydrogen phosphate is added to the oil-based lubricant to improve its electrical conductance and to make it an ionic conductor. This method enables not only the formation of uniform molybdenum/iron phosphate films on cast iron surfaces but also the in situ repair of such films after damage has occurred.

Abstract: Anodic formation of amorphous iron phosphate films in a dialkyl hydrogen phosphate electrolytic medium containing hydrogen-rich cation exchange resin particles having a free moisture content between about 9% and about 33% by weight.

Abstract: A method of using an electrochemical process in oil-based lubricants to form friction-reducing and wear-reducing iron phosphate films on metal surfaces. An electrolytic additive of dialkyl hydrogen phosphate is first added to the oil-based lubricant to improve its electrical conductance and to make it an ionic conductor. This method enables not only the formation of uniform iron phosphate films on metal surfaces but also the in-situ repair of such films after damage has occurred.

Abstract: A battery includes a negative electrode comprising metallic lithium (Li) in conjunction with lithium chlorate (LiClO.sub.3) electrolyte. Lithium perchlorate (LiClO.sub.4) may also be used as the electrolyte. Lithium chloride (LiCl) and lithium oxide (Li.sub.2 O), individually or together, may also be utilized with lithium chlorate or lithium perchlorate in forming the electrolyte. A positive electrode comprises a metal, such as nickel. In one form, a sheet of lithium metal is sandwiched between two sheets of nickel comprising a negative electrode, one nickel sheet being perforated to permit contact between the lithium sheet and a lithium chlorate electrolyte contained within an insulative member, the other electrode comprising a film of metallic nickel disposed upon the insulative member and in contact with the electrolyte; alternatively, a film or sheet of lithium metal may be disposed upon the insulator as a negative electrode.