Abstract: method and apparatus for aligning a photoreceptor, such as a CCD array, at a back focal plane of a lens, as may be employed in the construction of a sensor of an imaging system, employs a pair of sine-wave gratings arranged perpendicularly to each other and disposed in front of the lens. An illuminating beam of collimated monochromatic light propagates through the gratings and the lens to form a two-dimensional diffraction pattern on the photoreceptor. Beam splitting optics are employed between a source of the illuminating beam and the gratings to split the illuminating beam into a first beam and a second beam which are inclined equally to an optical axis of the lens to produce two of the foregoing diffraction patterns offset from each other in a resulting composite diffraction pattern. Elements of the pattern undergo displacement from their correct positions in response to a tilting and/or displacement of the photoreceptor from its correct position and orientation in the back focal plane.

Abstract: A method for determining the mass isotope enrichment of a subunit from which a biopolymer is formed, and the rates of synthesis and decay of the biopolymer. The mass isotope enrichment of the subunit is determined by comparing the mass isotopomer distribution of the biopolymer after administration of a mass isotopically labeled subunit, with the expected frequencies of the different mass isotopomers produced from a given subunit mass isotope enrichment. To determine the synthesis rate of the biopolymer, the expected frequency of a selected biopolymer mass isotopomer, calculated from the subunit isotope enrichment, is compared with the actual frequency of that biopolymer mass isotopomer. To determine biopolymer decay, the decay rate of high mass isotopomers of the biopolymer is determined.

Abstract: An adjustable hand-held pump adapted to measure microliter quantities of liquids includes a frame having a handle with a cylindrical opening formed therein. A threaded shaft is disposed and slidable within the cylindrical opening. A volume adjustment wheel is rotatably disposed within the frame at a stationary axial position and mechanically engages the threaded shaft to position the threaded shaft at a predetermined axial position within the cylindrical opening, thereby providing liquid volume adjustment.

Abstract: A method and apparatus for transferring a reaction gas between a high pressure environment and a low pressure environment. A baffle channel is disposed in a fluid communication path between the high pressure environment and the low pressure environment. Also disposed in the path is an element for limiting gas flow conductance. A shield gas is introduced into the baffle channel and a longitudinal laminar counterflow of the shield gas established toward the high pressure environment, opposing the flow of the reaction gas toward the low pressure environment.

Abstract: This invention is a process for detecting low levels of nitrogen oxides (NO.sub.x) in a flowing gas stream (typically an exhaust gas stream) and a catalytic NO.sub.x sensor which may be used in that process.

Abstract: A kit of slide-like articles that includes a stack of slide test elements and a separate stack of containers bearing a sealed liquid, the containers and test elements having substantially the same outside dimensions so that the containers are processable just like a slide test element. The seal of the container is penetratable by a pipette tip.

Abstract: An indicator for use in a luminescence-optical configuration for continuous and reversible measurement of the pH of a sample within a relevant measuring range (M), whose luminescence decay time .tau. is dependent on the pH of the sample, is characterized by the following properties. The pK.sub.a value of the acidic or basic indicator is in the relevant measuring range when the indicator is in its electronic ground state (S.sub.0). The protonation rate k.sub.p of the base, or deprotonation rate k.sub.dp of the acid in the excited state (S.sub.1, X) of the indicator is lower than the decay rate k.sub.A of the excited state, and the luminescence decay times .tau..sub.S and .tau..sub.B of the acidic forms (AH*, BH.sup.+*) and the basic forms (A.sup.-*, B*) of the indicator are different from each other. If the pK.sub.a .tau. value of the indicator in its electronically excited state (S.sub.1, X) is within the relevant measuring range, the protonation rate k.sub.p of the base, or deprotonation rate k.sub.

Abstract: Liquids for cleaning, disinfecting and lubricating dentistry handpieces are distributed to the handpieces by a device which includes reservoirs for storing liquids for the cleaning, disinfection and lubrication procedures which are to take place, and a series of solenoid valves for sequentially opening at different stations according to a prescribed cycle. To this end, each liquid to be utilized is conveyed through each handpiece in actual liquid form, and not in an atomized form, and then atomized in the handpiece by compressed air entering through a conduit which is separate from the conduit for passing the liquids.

Abstract: This invention relates to a compact and portable detection apparatus for ro-aromatic based chemical compounds, such as nitrotoluenes, dinitrotoluenes, and trinitrotoluene (TNT). The apparatus is based upon the use of fiber optics using filtered light. The preferred process of the invention relies upon a reflective chemical sensor and optical and electronic components to monitor a decrease in fluorescence when the nitro-aromatic molecules in aqueous solution combine and react with a fluorescent polycyclic aromatic compound.

Abstract: Methods of conducting Thin Layer Chromatography (TLC) involving using a TLC plate having sample spots and including no support material, placing the TLC plate on a porous substrate, and allowing solvent to move upwardly from the porous substrate toward the TLC plate by capillary action to be vaporized from the surface of the TLC plate, thereby concentrating the sample spots developed in the thin layer on the surface of the TLC plate.

Abstract: Methods are provided for using Nuclear Magnetic Resonance (NMR) spectroscopy to measure the bulk volume of oil and water in the polyurethane liner of sponge core. The method is accurate, rapid, and non-destructive. It provides information simultaneously in oil composition and viscosity.

Abstract: Devices are provided for analyzing a fluid cell containing sample. The devices comprise a solid substrate, microfabricated to define at least one sample inlet port and a mesoscale flow system. The mesoscale flow system includes a sample flow channel, extending from the inlet port, and a cell handling region for treating cells disposed in fluid communication with the flow channel. The devices may further include a structure inducing flow of cells in the sample through the flow system. In one embodiment, the cell-handling region may comprise a cell lysis structure to enable the lysis of cells in the sample, prior to, e.g., the detection of an intracellular component in the cell sample. In another embodiment, the cell handling region may comprise a cell capture region, comprising binding sites which reversibly bind to a specific population of cells in the cell sample, to permit the isolation of the specific cell population from the sample.

Abstract: A method which comprises using a specified dye taken up by erythrocytic nucleated cells so that their nuclei are stained and can be readily differentiated from other cells by measurement with a flow cytometer is disclosed. The method relies basically upon flow cytometry by two-step staining that uses a first fluid that is an acidic hypotensive fluorescent dye solution and a second fluid that is a solution that changes the osmorality and pH of the first fluid. The first fluid further contains a fluorescent dye that diffuses into erythroblasts to specifically stain their nuclei, and a group of erythroblasts is separated from other cell groups on the two-dimensional plot constructed with the flow cytometer, whereby the results of erythroblast differentiation are computed.

Abstract: An ionization fire detector of the type including a measuring chamber and a reference chamber having a common electrode which is connected to the gate terminal of a field-effect transistor by a profile piece of conductive caoutchouc having one end contacting the gate terminal and another end contacting the common electrode.

Abstract: Devices and methods are provided for the clinical analysis of a sperm sample. The devices comprise a solid substrate, typically on the order of a few millimeters thick and approximately 0.2 to 2.0 centimeters square, microfabricated to define a sample inlet port and a mesoscale flow channel extending from the inlet port. In one embodiment, a sperm sample is applied to the inlet port, and the competitive migration of the sperm sample through the mesoscale flow channel is detected to serve as an indicator of sperm motility. In another embodiment, the substrate of the device is microfabricated with a sperm inlet port, an egg nesting chamber, and an elongate mesoscale flow channel communicating between the egg nesting chamber and the inlet port. In this embodiment, a sperm sample is applied to the inlet port, and the sperm in the sample are permitted to competitively migrate from the inlet port through the channel to the egg nesting chamber, where in vitro fertilization occurs.

Abstract: A valve for use in a pipette gun for selectively providing different ranges of flow rates through a pipette cooperating with the pipette gun. The valve has a predetermined number of discrete settings, each of which provides a range of fluid flow rates between zero and a different maximum flow rate. The operator controls the flow rate by depressing the gun trigger a selected distance. To change the flow rate setting, the operator simply rotates the gun trigger to a desired setting. The present valve also eliminates the "piston effect" of prior art valve elements by isolating the pipette chamber while the valve element operably slides in and out of engagement with a port thereby connecting the pipette with a fluid source either under pressure or at a vacuum.

Abstract: Focusing a generated radiation signal on a detector is effected by a curvilinear surface. The radiation beam signal from the reflected surface is collimated or focused on the detector. Light scattered, Raman scattered, fluorescence, chemiluminescence, phosphorescence radiation signals from particles as a result of a chemical procedure or reaction is enhanced through this focusing technique. The enhanced signal which is detected is subsequently measured through different detection techniques.

Abstract: An automatic analyzing apparatus of this invention has first and second reaction container holders, a photometric unit, and a control unit. Each of the first and second reaction container holders is movable along a reaction line and has a plurality of reaction containers to which a liquid sample such as blood or urine can be injected. The photometric unit has a function of optically analyzing a concentration of a chemical component of the liquid sample injected in the reaction containers of the first and second reaction container holders when the first and second reaction container holders pass through it. A control unit has a function of stopping only either one of the first and second reaction container holders on the reaction line and moving the other reaction container holder along the reaction line to pass through the photometric unit.

Abstract: A method of determining the binder content of bituminous building material including a mixture of a mineralic constituent, a bituminous binder and moisture comprises the steps of: preparing a sample of the material, heating the sample to a temperature between 300.degree. to 550.degree. C.

Abstract: A device for removing and re-applying a cover to an open container of a liquid aspirated in an analyzer, the device including a plurality of receptacles disposed in an array for holding a plurality of containers of a liquid, a cover for each of the receptacles of a size and shape sufficient to sealingly cover a container in each receptacle, a mechanism for permanently attaching the cover to the receptacle, the mechanism including a retainer of each of the covers that is pivotally mounted on the receptacle and a bi-stable pivot in the device for pivoting and holding the retainer and thus its cover in either a first position in which the cover contacts and closes a container, or a second position in which the cover is held raised away from contact with any container in the receptacle by means of a leaf spring pressed against a cam.