Abstract: A device for compensating the temperature sensitivity normally associated with an integrated optical waveguide grating device has a temperature compensating slab waveguide region. This compensating region is provided within the slab waveguide region normally present in the grating device by modifying a sub-region of a predetermined shape and dimension to change its temperature coefficient of refractive index. This method and device can be applied to reflective and transmissive diffraction gratings and to phased array waveguide gratings.

Abstract: A method and system is provided for enhanced ultrasonic detection and imaging of small defects inside or at the surface of an object. The Synthetic Aperture Focusing Technique (SAFT) has been used to improve the detectability and to enhance images in conventional ultrasonics and this method has recently been adapted to laser-ultrasonics. In the present invention, an improved version of the frequency-domain SAFT (F-SAFT) based on the angular spectrum approach is described. The method proposed includes temporal deconvolution of the waveform data to enhance both axial and lateral resolutions, control of the aperture and of the frequency bandwidth to improve signal-to-noise ratio, as well as spatial interpolation of the subsurface images. All the above operations are well adapted to the frequency domain calculations and embedded in the F-SAFT data processing. The aperture control and the spatial interpolation allow also a reduction of sampling requirements to further decrease both inspection and processing times.

Abstract: A method and apparatus is disclosed for enhanced laser-induced plasma spectroscopic analysis of unknown heterogeneous materials. The apparatus has high power pulsed lasers with their beams focused on the material, typically two colinear lasers providing two pulses in the ultraviolet and in the near infrared spectral area. The first laser pulse vaporizes a small volume at the surface of the material and produces a plasma which is subsequently enhanced by the second laser pulse. The optical emission of the plasma is analyzed with a colinear optical spectrometer. The pulsed spectrum is detected by a gated photodiode array detector or by an array of photomultipliers each individually positioned to detect a line emission representative of a given element present in the material. The combination of the two laser pulses, appropriately synchronized, provides a plasma emission that is significantly stronger than a single laser pulse of the combined energy of the two pulses.

Abstract: A method and apparatus for rapid in-situ spectroscopic analysis of unknown heterogeneous materials is disclosed. The apparatus uses a high power pulsed laser whose beam is focused on the material, typically a porous compound of unknown composition such as an amalgamated powder or a mineral sample. The pulsed laser beam vaporizes a small volume of the material and produces a plasma having an elemental composition which is representative of the material composition. The optical emission of the plasma is analyzed with an optical spectrometer. The pulsed spectrum is detected by a gated photodiode array detector or by an array of individually positioned photomultipliers, to detect a background emission and a line emission representative of a given element present in the material.

Abstract: Post-compaction treatments of iron compacts to improve the mechanical strength of the compacts are provided. Powder is compacted into the desired part. The part is then subjected to a strengthening operation. This operation involves a heat treatment at a moderate temperature combined with an optional resin impregnation. The heat treatment is done at a temperature sufficient to increase the mechanical properties of the compact while maintaining the magnetic losses low for the required application. Impregnation with an insulating binder can be effected to increase the mechanical strength of the part without creating electric contacts between the powder particles.

Abstract: The present invention relates to particle agglomeration of aluminum powder using a lubricating binder. The resulting powder has improved flowability and can be shaped easily. The aluminum particles are admixed with a lubricant, e.g. polyethylene, and are held together by the lubricant. To agglomerate the aluminum powder, the lubricant is melted and is then solidified to form solid bridges between the aluminum powder particles. The lubricant may be burned out cleanly at temperatures lower than 450.degree. C.

Abstract: Aluminum powder compositions intended for powder metallurgy applications are provided. The powder compositions contain aluminum and aluminum alloys or blends made from elemental powders, admixed with a polyethylene lubricant. The polyethylene admixture eases the compaction of powders and the ejection of parts. As compared to other conventional admixed lubricants used for Al powder metallurgy applications, polyethylene allows to obtain parts with higher green and sintered strengths. Proper delubrication prior to sintering is of importance.

Abstract: A composite part consisting of a metallic matrix and reinforcing fibers is fabricated by the simultaneous winding of the fiber and plasma spraying of the matrix onto a rotating mandrel, wherein an axi-symmetric part is produced with multiple layers of the fibers aligned in the circumferential direction. Single or multiple fiber strands are wound onto a mandrel and simultaneously sprayed with the heated powder matrix material using a thermal spray process. Rotation and translation of the mandrel produces an axi-symmetric composite part. The content of the fiber material in the plasma sprayed matrix is typically up to 40% by volume. The light-weight composite part is produced in a single processing step. The part may be used either directly, or as an insert in other components with or without further densification.

Abstract: Biological fluids, e.g. bodily fluids such as plasma/serum, semen, milk or blood, can be treated efficiently with ozone to inactivate certain viruses, bacteria, fungi etc. To effect and enhance the contact of such fluids with ozone, or another disinfecting or deactivating gas, the fluids are thoroughly nebulized, or atomized, i.e. dispersed into minute droplets. Nebulization has been found to afford a faster O.sub.3 -fluid reaction rate than other known methods. It is proposed to create a fine "rain" of droplets to fall through a controlled atmosphere of O.sub.3 /O.sub.2 and/or O.sub.3 /inert gas mixture. Electric and magnetic fields are superimposed over the space through which the droplets are passed.Three types of nebulizers/atomizers are described: compressed gas (O.sub.3 /O.sub.2 mixture) atomizer, ultrasonic nebulizer, and rotary nebulizer.The invention was tested on coliphage MS2 which is safe, easy to handle, and more resistant to chemical disinfections than viruses such as HIV. More than 7 log.sub.

Abstract: A sound-insulating cap is designed for conventional microphones without EMI protection. In an environment where EMI is likely to affect the performance of a conventional microphone, the cap is used to eliminate a substantial part of the acoustic noise and thus assess whether EMI is present during the measurements using the microphone. The cap has a member snugly fitting over the receptor of a microphone, the member made of a number of layers of acoustically different materials. Venting is provided to prevent a damage to the membrane of the microphone during the installation and removal of the cap.

Abstract: Known organic solderability preservatives (OSP) contain an azole compound and are applied on a copper surface from an acidic solution. The OSPs are not visible to the naked eye when applied. A number of dyes compatible with the OSP solution and not interfering with solderability has been identified. The composition containing such a dye can produce a layer which is visible to the naked eye when applied even in a thin layer. The suitable dyes contain a cationic imine group having the general formula ##STR1## where X.sup.- is an anion such as chloride, iodide, sulphate, etc., or an organically bonded anionic group such as sulphonate.

Abstract: Abrasion-wear resistant thermal sprayed stainless steel based coatings are disclosed, particularly arc sprayed stainless steel coatings containing titanium diboride crystals which impart hardness to the soft stainless steel matrix and enhance their resistance to hard abrasive media. There is also disclosed a process for making core wires composed of stainless steel sheaths and cores composed of a mixture of titanium diboride, stainless steel and certain additives. During the thermal spraying operation, the stainless steel sheath and the core material melt to form a composite coating containing fine hard titanium boride crystals dispersed within stainless steel. The arc sprayed stainless steel based coatings are more resistant to abrasion wear than solid pieces of type 304 stainless steel and other arc-sprayed stainless steel-based coatings available on the market.

Abstract: Ultrasonic buffer rods are useful for on-line process control of industrial material processes at elevated temperatures. In order to increase the signal-to-noise ratio in the reflected ultrasonic waves revealing the information of the condition of the materials being processed, clad ultrasonic waveguides consisting of a tapered or uniform core and a cladding are proposed. The core is made of a low ultrasonic loss material. Preferably, the cladding has a higher ultrasonic velocity than the core. The cladding may be thermally sprayed over the core. The waveguides are simple, rugged, machinable and operable at elevated temperatures.

Abstract: A method for producing composite insulating coatings on powder particles, the coatings containing an electrically insulating metal compound and an organic polymer. The coatings are deposited preferably by controlled spraying, simultaneous or sequential, of sol precursors of insulating metal compounds and polymer emulsions or solutions onto polymer, metal or ceramic powder particles preferably during the blending or mixing of the particles. The process is useful for mass production of coated iron-based powders used for shaping components by powder metallurgy techniques for magnetic applications. Coated iron based powders can be cold or warm pressed and heat treated to obtain the desired mechanical properties.

Abstract: A method and apparatus for rapid in-situ spectroscopic analysis of preselected components of homogeneous solid chemical compositions, especially pharmaceutical products. The apparatus comprises a high-power pulsed laser whose beam is focused on the material, typically a tablet or the powder prior to compaction into the tablet, which generally consists of an active ingredient (e.g. a drug) and a filler material (cellulose, glucose, lactose, etc.). The pulsed laser beam vaporizes a small volume of the pharmaceutical product and produces a plasma having an elemental composition which is representative of the pharmaceutical product. The atomic composition of the vaporized material is analyzed with an optical spectrometer.

Abstract: A process and apparatus for the continuous solid state forming of semicrystalline polymers using roll-drawing is disclosed. The output of an extruded thick polymer profile is stabilized by a gear pump. The profile is passed through a die for the desired geometry and a cooling calibrator. The profile is heat conditioned in heating tunnels to a temperature below the melting point prior to deformation between sets of rolls. A plurality, e.g. four pairs of rolls apply both compression and tension to the polymer profile. The tension applied on the profile, the roll gap, the linear speed of the profile and its temperature are monitored and controlled for the amount of polymer deformation and relaxation allowed. High tensile modulus and strength, both in the longitudinal and transverse direction of the polymeric strip, can be achieved.

Abstract: A method for producing fine-grained lamellar microstructures in powder metallurgy (P/M) and wrought gamma titanium aluminides comprises the steps of: (a) a cyclic heat treatment at a maximum temperature in the range of about 10.degree. C. above to about 10.degree. C. below the alpha-transus temperature (T.sub..alpha.) of the alloy, and (b) a secondary heat treatment of thus cyclically heat treated alloy at a temperature between 750.degree. C. and 1050.degree. C. for 4 to 100 hours. For cast gamma alloys, the method comprises additionally the step of a solution treatment at a temperature in the range of about 30.degree. C. to 70.degree. C. above T.sub..alpha. followed by a water or an oil quench before the two steps described above. The alloys with the resulting fine-grained lamellar microstructure have an advantageous combination of mechanical properties--tensile strength, ductility, fracture toughness, and creep resistance.

Abstract: A new panoramic/fish-eye imaging system for projecting a 360 degree cylindrical field of view onto a two-dimensional annular format is described. It is rotationally symmetrical and comprises two groups of optics, each having very distinct functions. The front group of optics is basically a catoptric system employing a concave and convex mirror for converting the extreme field angles to a more manageable intermediate image. The rear group acts as a relay lens to transfer the intermediate image formed by the front group to some accessible location downstream. For improved overall performance, aberration compensation of the front group is included in the design of the relay optics. A further refinement to the design is the inclusion of an additional optical element in the form of refracting negative shell located in front of the entire arrangement. This increases the effective field of view and is useful when fields of view exceeding 180 degrees are required.

Abstract: An optical lens is useful as a D-shape laser beam projector. The lens consists of a known linear diverging element enabling the expansion of a laser beam into an uniform line, and a matching section of an axicon, either a symmetrical half-axicon or a non-symmetrical one, cut in a plane passing through, or nearly through, its apex. The two components, joined together in a plane of cutting of the axicon section, are positioned in a laser beam such that the beam is incident on both apices of the linear diverging element and the axicon section.

Abstract: An apparatus for exposing laboratory animals to test substances comprises, generally, at least two supply manifolds for supplying each a gaseous or a vaporous substance, an exhaust manifold for removing an exhalate of said animals and unused portion of said test substance, and a plurality of inhalation chambers. Each chamber is dimensioned to accommodate a nasal part of the animal's head and is in fluid communication with the at least two supply manifolds and with the exhaust manifold. The apparatus is designed to prevent the streams of test substances hitting the animal's nostrils and causing an avoidance reaction.