摘要:
A device is described for sensing oxygen, particularly for use in medical applications. The device includes an optical waveguide and an oxygen sensing medium disposed on the waveguide. The sensing medium fluoresces in response to light from a light source such that the intensity of fluorescence is dependent on the partial pressure of oxygen in the environment. The sensing medium includes an oxygen sensitive fluorescent dye in a matrix consisting of a plasticized polymer.
摘要:
A process of forming an array of powder samples arranged in predefined locations where all samples have a flat surface in a common plane has been developed. A main support having at least N perforations from a first surface of the main support through a second surface of the main support in predefined locations, where N is the number of samples in the array is provided. The main support is equipped with a flat support temporarily attached to its first surface. All N samples are loaded simultaneously with sample X in perforation X of the main support where X is an integer from 1 to N. A flat surface of each sample where the flat surfaces are a common plane is formed by forcing the samples within the perforations against the flat support. The samples are retained in position within the perforations against the flat support, and are made ready for analysis by exposing the flat surfaces of the samples by removing the flat support. The exposed flat surfaces of the samples are in predefined locations and are all in a common plane. Alternatively, the flat support may be permanently attached to the main support.
摘要:
A hydrolyzed dye/gel polymer for use in a pH-based sensor is characterized by its chemical and optical stability with respect to dye loss with time. Preferably, the dye/gel polymer is hydrolyzed by heating in a dilute base solution for a period of time sufficient to remove weakly bonded dye molecules from the polymer, then washed to remove the base solution and loose dye.
摘要:
An apparatus and process for forming an array of powder samples arranged in predefined locations where all samples have a flat surface in a common plane has been developed. A monolithic block having a main support section having at least N perforations from a first surface of the main support through a second surface of the main support in predefined locations, where N is the number of samples in the array is provided. The monolithic block also has a flat support section covering the perforations of the main support section. All N samples are loaded simultaneously with sample X in perforation X of the main support where X is an integer from 1 to N. A flat surface of each sample where the flat surfaces are a common plane is formed by forcing the samples within the perforations against the flat support. The samples are retained in position within the perforations against the flat support, and are made ready for analysis since the flat surfaces of the samples are in predefined locations and are all in a common plane.
摘要:
A method for rapidly screening multiple X-ray powder diffraction patterns, such as those generated through combinatorial chemistry, has been developed. The method is directed toward measuring X-ray powder diffraction patterns of a set of samples, factoring the patterns using a suitable statistical technique into a small number of discrete components or factors, determining the scores corresponding to the factors for each X-ray powder diffraction pattern, and plotting the scores. The graphs of the scores are then inspected for clusters, trends, or outliers, which may represent new material or, perhaps, faulty data.
摘要:
A multiple sensor which can be readily inserted into, and removed from a radial arterial cannula for use in continuous in vivo patent monitoring includes a plurality of individual sensors, each sensor including a sensing element disposed on an optical waveguide, the sensors being bonded together by an adhesive without covering the sensing elements.
摘要:
A multiple sensor which can be readily inserted into, and removed from a radial arterial cannula for use in continuous in vivo patent monitoring includes a plurality of individual sensors, each sensor including a sensing element disposed on an optical waveguide, the sensors being bonded together by an adhesive without covering the sensing elements.
摘要:
Control of many chemical processes is optimized using compositional data, rather than physical properties, as the means of control. Using near infrared spectroscopy as the analytical tool affords the opportunity for on-line measurements in real time. A calibration set of NIR spectra bounding the acceptable process space within which a particular property is to be controlled is obtained by conventional means. Applying a multivariant statistical method to the calibration set affords a method of identifying the most important characteristics of the set which governs the controlled property, and is inherently related to the composition of the process product. Control then is effected by using only a small number (2-4) of such characteristics, which can be determined quickly and simply from the measured spectra, as the control criteria to be applied to the process as a whole. The result is a very effective way of controlling a complex process using only 2-4 non-obvious criteria objectively determined from a calibration set and which can be applied in real time and virtually continuously resulting in a well-controlled process whose product composition is (ideally) invariant.
摘要:
The observation was made that virtually all octane number variations arise from 23 components present in a broad variety of gasolines. Consequently it is possible to develop a calibration set consisting of a gasoline base stock as modified by one or more of the 23 components. By measuring the octane number and near infrared spectrum of each member of the calibration set, the octane number of any sample at the site specific for the base stock may be determined from the near infrared spectrum of the sample.
摘要:
An electrode for use in miniaturized sensor applications includes an electrically conductive element, a first layer of a salt on the surface of the conductive element having a common cation with the conductive element, a second layer of a second salt coating the first layer, the second layer having a common anion with the first layer, and a membrane covering the second layer, wherein the electrode is completely anhydrous when formed. The membrane may be selected to form either an ion selective electrode or a reference electrode.