Abstract:
Systems and methods for measuring the isotope ratio of one or more trace gases and/or components of gas mixtures such as different gas species present in a gas mixture. The system includes a resonant optical cavity having two or more mirrors and containing a gas, the cavity having a free spectral range that equals the difference between frequencies of two measured absorption lines of different gas species in the gas, or of two different isotopes, divided onto an integer number. The system also includes a continuous-wave tunable laser optically coupled with the resonant optical cavity, and a detector system for measuring an absorption of laser light by the gas in the cavity. The detector system includes one of a photo-detector configured to measure an intensity of the intra-cavity light or both a photo-acoustic sensor configured to measure photo-acoustic waves generated in the cavity and a photo-detector configured to measure an intensity of the intra-cavity light.
Abstract:
Devices to detect a substance and methods of producing such a device are disclosed. An example device to detect a substance includes a housing defining an externally accessible chamber and a seal to enclose at least a portion of the chamber. The example device also includes a substrate includes nanoparticles positioned within the chamber. The nanoparticles to react to the substance when exposed thereto. The example device also includes a non-analytic solution within the chamber to protect the nanoparticles from premature exposure.
Abstract:
Described herein is a spectroscopic system and method for measuring and monitoring the chemical composition and/or impurity content of a sample or sample stream using absorption light spectroscopy. Specifically, in certain embodiments, this invention relates to the use of sample pressure variation to alter the magnitude of the absorption spectrum (e.g., wavelength-dependent signal) received for the sample, thereby obviating the need for a reference or ‘zero’ sample. Rather than use a reference or ‘zero’ sample, embodiments described herein obtain a spectrum/signal from a sample-containing cell at both a first pressure and a second (different) pressure.
Abstract:
Method and apparatus testing engine component, for blockage of one or more through-holes in a portion of a wall. The method including (i) providing a supply of test fluid, (ii) causing or permitting flow of test fluid to occur from first to second region, (iii) illuminating the second region with electromagnetic radiation to cause scattering of electromagnetic radiation by material exiting substantially non-blocked through-holes in wall portion having passed therethrough from the first to second side, (iv) detecting said scattering of electromagnetic radiation from said substantially non-blocked through-holes; and (v) comparing said detected scattering of electromagnetic radiation from said substantially non-blocked holes with known pattern of through-holes in component wall portion to determine the presence and/or location and/or identity of any blocked or partially blocked through-holes in component wall portion.
Abstract:
A microplate reader and method has at least one measuring device and a holding device for accommodating at least one microplate and for positioning samples-containing wells of microplates in relation to the measuring device. The at least one measuring device is used for detecting light emitted by samples in wells of a microplate and/or which is influenced by samples transilluminated by light in the wells. The microplate reader has a control unit for controlling the composition of a gas atmosphere surrounding the wells containing the samples. A respective use is characterized particularly in that living cells are measured in a controlled gas atmosphere, wherein the living cells are chosen from microaerophilic, optionally anaerobic and obligatorily anaerobic microorganisms as well as fungi and eukaryotic cells.
Abstract:
Systems and methods for measuring the isotope ratio of one or more trace gases and/or components of gas mixtures such as different gas species present in a gas mixture. The system includes a resonant optical cavity having two or more mirrors and containing a gas, the cavity having a free spectral range that equals the difference between frequencies of two measured absorption lines of different gas species in the gas, or of two different isotopes, divided onto an integer number. The system includes a continuous-wave tunable laser optically coupled with the resonant optical cavity and a detector system for measuring an absorption of laser light by the gas in the cavity. The detector system includes a photo-detector to measure an intensity of the intra-cavity light, or both a photo-acoustic sensor to measure photo-acoustic waves generated in the cavity and a photo-detector to measure an intensity of the intra-cavity light.
Abstract:
Systems and methods for measuring the isotope ratio of one or more trace gases and/or components of gas mixtures such as different gas species present in a gas mixture. The system includes a resonant optical cavity having two or more mirrors and containing a gas, the cavity having a free spectral range that equals the difference between frequencies of two measured absorption lines of different gas species in the gas, or of two different isotopes, divided onto an integer number. The system includes a continuous-wave tunable laser optically coupled with the resonant optical cavity and a detector system for measuring an absorption of laser light by the gas in the cavity. The detector system includes a photo-detector to measure an intensity of the intra-cavity light, or both a photo-acoustic sensor to measure photo-acoustic waves generated in the cavity and a photo-detector to measure an intensity of the intra-cavity light.
Abstract:
An apparatus for optical measurement of a liquid or molten material, which has: a transparent container which has a bottom face and is capable of containing a to-be-measured material therein, with the bottom face at least having a flat face and being transparent; and an optical device that irradiates a light to the bottom face of the container and that detects and measures a reflected light from the bottom face; and a method for optically measuring a liquid or molten material using the apparatus.
Abstract:
The invention concerns a gas analyzer comprising: a measuring volume (2), a radiation source (1) for providing a beam to pass said measuring volume; a heat sink (16) for said radiation source; at least one thermal detector (3) having a hot junction within a support structure and receiving the radiation and a cold junction for reference within the same support structure and protected from said radiation; at least one optical bandpass filter (9) between said hot junction and said radiation source; and a thermal mass (11), which is formed of a material having high thermal conductance. The thermal mass has a cavity with a bottom step (34) and a rim (32), and a first length therebetween. The support structure has a frontal edge (35) and a base plate lip (33), and a second length therebetween. There is a radial gap between the thermal mass and the support structure. Press means urge said support structure in the cavity, whereupon a more efficient thermal contact is either between said frontal edge and said bottom step, or between said base plate lip and said rim. A first thermal barrier (17) is between the heat sink and the thermal mass, and a second thermal barrier (22) surrounds the thermal mass. A shield (19) formed of a material having high thermal conductance covers said second thermal barrier and is in thermal contact with said heat sink.
Abstract:
A method for improving the measurement of semiconductor wafers is disclosed. In the past, the repeatability of measurements was adversely affected due to the unpredictable growth of a layer of contamination over the intentionally deposited dielectric layers. Repeatability can be enhanced by removing this contamination layer prior to measurement. This contamination layer can be effectively removed in a non-destructive fashion by subjecting the wafer to a cleaning step. In one embodiment, the cleaning is performed by exposing the wafer to microwave radiation. Alternatively, the wafer can be cleaned with a radiant heat source. These two cleaning modalities can be used alone or in combination with each other or in combination with other cleaning modalities. The cleaning step may be carried out in air, an inert atmosphere or a vacuum. Once the cleaning has been performed, the wafer can be measured using any number of known optical measurement systems.