Abstract: The present invention provides a means and a device to control relative humidity and airborne contaminants within a defined environment. The devices and methods of the present invention enable a user to regulate the relative humidity of a defined environment and insure that extreme conditions, e.g. less than 15% or greater than 90% relative humidity, do not exist. The air quality control system can also be used to control the relative humidity in and about a narrow range. Control over relative humidity and airborne contaminants is achieved by combining an appropriate salt and water solution, such as a saturated salt solution with a solid phase of that salt, with an isolation membrane and a getter system. The present invention is particularly useful for housing sensors, such as SIR sensors, which are sensitive to relative humidity extremes.

Abstract: A combustion device comprises a porous distributive layer, a combustion chamber disposed downstream of the porous distributive layer, and an emissive matrix in an active flame zone in the combustion chamber of the device downstream from the porous distributive layer. The emissive matrix comprises a three dimensional matrix structure made of heat absorbing, heat radiating, and heat conducting bodies. The device includes a blower for delivering a fuel/oxidizer mixture at sufficiently elevated pressure to an upstream face of the porous distributive layer to distribute the active flame zone substantially throughout the emissive matrix.

Abstract: The present invention provides an apparatus and method for determining the concentration and/or hazard from a target gas by means of optically monitoring one or more sensors that responds to the target gas by means of an optical change. The apparatus comprises a photon source optically coupled to the sensor and the photon intensity passing through the sensor is quantified by more than one photodiode in a system, so that the photon flux is a function of at least one sensor's response to the target gas, e.g., transmits light through the sensor to the photodiode. The photocurrent from the photodiode is converted to a digital sensor reading value proportional to the optical characteristics of the sensors and is loaded into a microprocessor or other logic circuit. In the microprocessor, the sensor readings are essentially differentiated to determine the rate of change of the sensor readings.

Abstract: A superemissive combustion device of this invention comprises a porous distributive layer and an apparatus for delivering a fuel/oxidizer mixture to an upstream face of the porous distributive layer. A superemissive advanced emissive matrix in is disposed within an active flame zone downstream from the porous distributive layer. The emissive matrix is in the form of a three dimensional matrix of radiating bodies that is optically thin to electromagnetic radiation. The emissive matrix is either formed from or includes a coating of a superemissive material that is selected to emit photons within a predetermined wavelength range when thermally stimulated. The emitted photons are received by one or more photovoltaic cells disposed adjacent the matrix.

Abstract: A method for making very strong gas mantles and other ceramic structures, and the resulting products, are provided. According to the method, an organic or composite structure is first pyrolyzed in the absence of oxygen to remove hydrogen, oxygen and nitrogen, leaving a porous carbon or composite structure, which is then impregnated with a metal compound-containing solution or slurry which is later fired in the presence of an oxidizing atmosphere to produce a refractory metal oxide which has about the same shape as the precursor carbon or composite structure. Due to minimal shrinkage of the mostly carbon or composite precursor, the resulting mantles and other ceramic structures have few defects in the fibers and great strength.

Abstract: A system for thermally stimulating a laser emissive device comprises a thermal generating device, a photon emissive device that is capable of generating photons upon exposure to thermal energy, a laser emissive source, and an optical waveguide interposed between the photon emissive source and laser emissive source to direct photons to the laser emissive source to effect photon stimulation of the same. The waveguide may be in the form of a light pipe comprising the photon emissive material, which material is disposed within the thermal energy source. The photon emissive material is selected to produce a specific wavelength of photons that are collected within and directed through the optical waveguide to a laser rod. The photons routed to the laser rod stimulate a specific wavelength laser emission. If desired, the system can also be used with more than one target, e.g., more than one laser device, or a photovoltaic cell to produce electricity.

Abstract: Nanofibers are produced having a diameter ranging from about 4 .ANG. to 1 nm, and a nano denier of about 10.sup.-9. The use of the electro-spinning process permits production of the desired nanofibrils. These fibrils in combination with a carrier or strengthening fibers/filaments can be converted directly into nonwoven fibrous assemblies or converted into linear assemblies(yarns) before weaving, braiding or knitting into 2-dimensional and 3-dimensional fabrics. The electrospun fiber can be fed in an air vortex spinning apparatus developed to form a linear fibrous assembly. The process makes use of an air stream in a properly confined cavity. The vortex of air provides a gentle means to convert a mixture of the fibril fed directly or indirectly from the ESP unit and a fiber mass or filament into an integral assembly with proper level of orientation. Incorporation of thus produced woven products into tissue engineering is part of the present invention.

Abstract: Surveillance systems of this invention incorporate a charge coupled device image sensor with an illumination source that is made of an emitter which concentrates its optical output in a narrow band at or about the peak optical response of the photoconverter being used. Where a silicon imaging sensor is being used, the illumination system can comprise an emitter made of a rare earth oxide, such as ytterbium oxide, in the form of a filamentary network and fuel to energize the emitter. Different emitters can be employed to achieve the optimal radiant energy for any type of photoconverter device, including those based on silicon, germanium, indium gallium arsenide, and gallium antimonide. These surveillance systems may be applied in a number of specialized applications, such as, for example, in the covert surveillance of commercial, industrial, residential, or military sites, or any site in which the visible illumination of the surveillance area is undesirable.

Abstract: The concentration of a target gas is determined in an optical gas sensor system having an array of optical gas sensors wherein each sensor has a different sensitivity range for a target gas. An active sensor is selected from the array of optical gas sensors by determining which sensor has an optical transmittance value between 0% and 100%. Optical transmittance values of the active sensor are differentiated with respect to time. Concentration of the target gas is calculated as a function of both the rate of change of optical transmittance and the value of the optical transmittance at the beginning of the period over which the transmittance is differentiated. When a hazardous gas such as carbon monoxide is the target gas an alarm can be given when a threshold concentration is exceeded. Preferably, the transmittance values are converted to digital signals and processed in an eight-bit microprocessor to determine target gas concentration.

Abstract: Portable, small, and light-weight radiant and/or electrical power generating sources, constructed according to the principles of this invention, comprise an air/fuel delivery device that houses a fuel canister of pressurized hydrocarbon fuel therein. The fuel canister includes a check valve that is selectively activated to release the pressurized hydrocarbon fuel to a pressure regulator and then through a venturi disposed within the delivery device. The delivery device includes an ignitor that is also activated when the fuel is released. A radiant head is attached to the delivery device and includes a luminous mantle in gas flow communication with the venturi and formed from a fibrous rare earth oxide. The head includes a lens and reflector system adjacent the mantle. Alternatively, or in addition to the radiant head, a thermophotovoltaic head can be attached to the delivery system.

Abstract: A thermophotovoltaic electric generating system provides high thermal to electric conversion efficiency by use of a sequence of matched radiation emitters and radiation collectors. The radiation emitters comprises ceramic materials which emit thermally stimulated quantum radiation in at least one characteristic wavelength bands when heated above a threshold temperature. By employing a sequence of selective emitters such as rare earth metal oxide, more than 50% of the radiation emitted from the surface can be concentrated in two or more characteristic wavelength bands. A sequence of corresponding photovoltaic device selectively absorbing and efficiently converting the radiation at the characteristic wavelength bands for high electric conversion efficiency in each zone, respectively. An overlying layer of the photovoltaic collector selectively absorbs at least one of such characteristic wavelength bands.

Abstract: Several new and useful compositions of rare earth oxides and mixtures of rare earth oxides are made into strong flexible fibrous textiles and strands. By varying the mixtures of rare earth metal oxides that make up the textiles and strands, the emission spectra can be matched to the absorption spectra of a variety of semiconductor photovoltaic cells. Furthermore, the addition of between 1-10 mol % of thorium oxide to the rare earth metal oxide fibers inhibits microcrystalline grain growth at high temperatures.

Abstract: A detector sensor system for sensing the presence of a toxic gas, such as carbon monoxide and/or smoke whereby a corresponding alarm is sounded. The presence of the gas is detected by passing light through a biomimetic sensing material in which the optical characteristics change in the presence of the target gas. This system includes a housing containing a light emitter, light detector and a mechanism for sounding an alarm. The sensing material is contained in a cell which, together with a battery to power the system, is mounted in a key insertable into the housing. The key may be readily inserted or withdrawn from the housing for replacement purposes. When fully inserted, the key positions the sensing cell means between the light emitter and detector means and brings the battery contacts carried therewith into connection with contacts associated with the system circuitry mounted within the housing.

Abstract: A multilayer matrix burner which has exceptionally low NO.sub.x emissions can be operated over a broad turndown range. The burner is, in effect, a three-dimensional matrix of spaced apart emissive layers. There is a first three-dimensional porous layer which acts to distribute a fuel/air mixture. There is a wider gap (which may be adjustable) between the distributive layer and one or more two-dimensional porous emissive layers. An exemplary emissive layer is a refractory wire screen. Preferably, there are multiple such emissive layers with a narrower gap between successive layers. Preferably, the porosity increases in each successive layer downstream from the preceding layer. This arrangement provides a stable flame wherein most of the combustion occurs adjacent to successive incandescent emissive layers. Preferably the successive layers in the downstream direction have a large open area for transmitting radiant energy from preceding emissive layers. Such high intensity burners, e.g. 1,500,000 BTU/h.multidot.

Abstract: Several new and useful compositions of rare earth oxides and mixtures of rare earth oxides are made into strong flexible fibrous textiles and strands. By varying the mixtures of rare earth metal oxides that make up the textiles and strands, the emission spectra can be matched to the absorption spectra of a variety of semiconductor photovoltaic cells. Furthermore, the addition of between 1-10 mol % of thorium oxide to the rare earth metal oxide fibers inhibits microcrystalline grain growth at high temperatures.

Abstract: A method for making rare earth metal oxide ceramic precursor composition comprising reacting a rare earth metal alkoxide with a complexing agent to give a mixture of complexing agent/alkoxide rare earth metal complexes is disclosed. The mixture is hydrolyzed and the precursor composition is isolated. Solubility of the precursor composition in non-polar or polar solvents is affected by the selection of complexing agent amongst other factors. At least partial dissolution of the precursor composition in a solvent gives a preceramic liquid which upon evaporation of the solvent and heating gives a rare earth metal oxide ceramic. Utility of the preceramic liquid include the formation of rare earth metal oxide fibers, thin films, coatings, foams, powders, cast or molded objects or it may be used as a ceramic adhesive.

Abstract: The present invention provides an apparatus and method for enhancing the response of a biometric sensor for sensing toxins by measuring the rate of change of sensor readings. An LED, optically coupled to the sensor and a photodiode, transmits light through the sensor to the photodiode. The photocurrent from the photodiode is converted to a digital sensor reading value proportional to the darkness of the sensor and is loaded into a microprocessor. In the microprocessor, the sensor readings are essentially differentiated to determine the rate of change of the sensor readings. The rate of change information is used to trigger an alarm condition indicative of a predetermined level of sensed toxins.

Abstract: An improved carbon monoxide sensor system has a dual sensor system having two sensors disposed in a series arrangement within a sensor housing. Each sensor is formed from a porous semi-transparent substrate that is impregnated with a different chemical sensor reagent. At lease one sensor substrate surface is treated with a chemical compound before being impregnated to increase average pore size and, thereby, increase the sensitivity of the sensor. One sensor is formed from a chemical sensor reagent designed to perform at a lower to middle humidity and temperature range. The other sensor is formed from a chemical sensor reagent designed to perform at a middle to high humidity and temperature range. The dual sensor system constructed in this manner provides good carbon monoxide sensitivity at temperature and humidity conditions required by the standards of UL-2034.

Abstract: An enclosure for a gas detector including an easily removable and replaceable battery/sensor holder and a battery absence indicator. The enclosure includes a flat first panel adapted to be fastened into a ceiling, a second panel spaced from the first panel to contain the gas detecting apparatus and a sidewall closing between the edges of the panels. A specially configured opening is provided to allow sound from an audio alarm to exit the enclosure. Another opening in the second side panel is configured to receive and retain a battery holder through a cooperating bayonet type arrangement of radial protrusions on the holder and notches in the sides of the opening. A tube is contained in the opening in such a way as to permit the tube to extend when the holder is removed to signal the absence of the holder. The tube is pushed back into the enclosure when the battery/sensor holder is inserted.

Abstract: The present invention provides an apparatus and method for enhancing the response of a biometric sensor for sensing toxins by measuring the rate of change of sensor readings. An LED, optically coupled to the sensor and a photodiode, transmits light through the sensor to the photodiode. The photocurrent from the photodiode is converted to a digital sensor reading value proportional to the darkness of the sensor and is loaded into a microprocessor. In the microprocessor, the sensor readings are essentially differentiated to determine the rate of change of the sensor readings. The rate of change information is used to trigger an alarm condition indicative of a predetermined level of sensed toxins.