A method of spatially measuring a plurality of nano-scale structures in a sample comprises the steps of: marking the individual structures at different locations with fluorescent markers, coupling the individual structures to individual positioning aids whose positions in the sample are known, exciting the fluorescent markers with excitation light for emission of fluorescence light, wherein an intensity distribution of the excitation light has a local minimum, arranging the local minimum at different positions in a close-up range around the position of respective positioning aid whose dimensions are not larger than the diffraction limit at the wavelength of the excitation light, registering the fluorescence light emitted out of the sample separately for the individual fluorescent markers and for the different positions of the minimum, and determining positions of the individual fluorescent markers in the sample from the intensities of the fluorescence light registered.

The present invention relates to a real time identification method of working/functional fluid products including a specified tagging material and an apparatus which is first capturing and then identifying the tagging material using a concentrator and an optical detector, simultaneously transferring the reading to a smart unit and finally releasing the tagging material.

An optochemical sensor comprises a measuring element excitable by the light of an excitation light source and in contact with a medium to be measured, and a measuring arrangement including at least one excitation light source and a detector as well as a hood separating the measuring arrangement from the measuring element, wherein the excitation light source and the detector are fixed to a base plate arranged in parallel with the measuring element, the hood, the excitation light source and the detector are separated from one another by at least a portion of the material thickness of the hood, and light from the excitation light source through an optical waveguide impinges on the measuring element at such an angle that fluorescence light emitted by the measuring element impinges perpendicularly on the detector.

The present invention provides a method for monitoring precipitation of at least one wax component from a hydrocarbon-containing fluid stream during the flow of said fluid stream through a fluid transport system having at least one in-flow point and at least one out-flow point. The method comprises: i) introducing at least one labelled wax into said hydrocarbon-containing fluid stream at at least one in-flow point; and ii) measuring the relative or absolute concentration of said labelled wax in at least one sample taken at at least one out-flow point. The method may comprise sampling and analysing wax components from the hydrocarbon-containing fluid, identifying suitable wax components and generating labelled waxed based upon such components. Methods of generating labelled waxes and their uses are provided, along with corresponding methods for asphaltenes.

The invention disclosed herein relates to novel ligands (Lx) of Formula-I for selective detection of Cr (III) in pure aqueous medium and industrially viable process for the preparation thereof. Further the invention provides the process of selective detection of Cr (III) by fluorimetry using novel ligands of Formula-I. The invention also discloses a method of solubilizing novel ligands of formula-I in pure aqueous medium with the aid of non-ionic surfactant. The invention discloses a method of selective detection of Cr (III) using novel ligands of Formula-I. ##STR00001##

The invention is a system and method to measure oil content in water utilizing the fluorescence of oil emitted under excitation by laser. Oil and water mixture is transferred through the system to a measurement section in a microscope, which produces high resolution 3-dimensional images of the oil and water mixture with the fluorescence. The images are analyzed to calculate the amount of oil in water and oil droplets distribution. The image is also analyzed to distinguish oil coated solids from oil droplets, and to calculate the sizes and volumes of the solids.

An aquatic environment water parameter testing system and related methods and chemical indicator elements. The aquatic environment water parameter testing system includes an electronics portion having an optical reader element and a sample chamber portion having a chemical indicator element which may be removably connected. A chemical indicator element may include an information storage and communication element used, in part, to provide identification of a chemical indicator of the chemical indicator element. Conductivity and/or temperature may be utilized to calibrate readings by the optical reader element. A chemical indicator element may also include a thin film material having particular optical characteristics tied to the light from a light source, such as a light source of an optical reader element.

Provided is a method for the detection of cyanide based on displacement of the glutathione ligand of glutathionylcobalamin by cyanide. The composition for detecting cyanide (CN.sup.−) including glutathionylcobalamin (GSCbl) and a buffer has specificity in which GSCbl does not react with other anions by nucleophilic substitution, but selectively reacts with only CN.sup.− by displacement. Further, the GSH bound to the Cbl reacts with CN.sup.− by nucleophilic substitution with high efficiency to enhance sensitivity, and cyanocobalamin (CNCbl), di-cyanocobalamin (diCNCbl) and glutathione (GSH) which are byproducts generated by nucleophilic substitution reaction of CN.sup.− may be qualitatively/quantitatively detected through spectrophotometric, naked eye, and fluorometric assays, respectively.

The present invention relates to a process for the detection and adsorption of arsenic from ground water and industrial waste water using lanthanide doped nanoparticles. More particularly, the present invention provides a process for the detection and adsorption arsenic in ppm level using Eu.sub.0.05Y.sub.0.95PO.sub.4 nanoparticles.

Detecting xanthan gum in a sampling location includes delivering a tagged polypeptide to the sampling location. The tagged polypeptide includes a polypeptide and a fluorescent probe bound to the polypeptide, such that the fluorescent probe is released from the polypeptide to yield an unbound fluorescent probe when the polypeptide interacts with xanthan gum. Light that excites the unbound fluorescent probe is directed toward the sampling location, and an intensity of fluorescence emitted from the unbound fluorescent probe is assessed, wherein a non-zero intensity is indicative of the presence of xanthan gum in the sampling location. A device for the detection of xanthan gum has a sensing region including the tagged polypeptide, a light source adapted to direct light to the sensing region, the light source adapted to provide one or more wavelengths of light to excite the fluorescent probe, and a detector for detecting fluorescence emitted from the fluorescent probe.