Abstract:
Apparatus for GPC/TREF and TREF/GPC characterization of a polymer sample. The apparatus provides for the automated and integrated use of multiple TREF columns and a GPC system employing a multiple flow through detectors. In addition, a method for TREF/GPC characterization of a polymer sample by GPC analysis of TREF fractions at increasing TREF elution temperatures from multiple TREF columns operated in a coordinated and synchronized temperature cycle for increased sample throughput. Also, a method for GPC/TREF characterization of a polymer sample by GPC fractionation followed by TREF fractionation of the GPC fractionations.
Abstract:
This invention provides methods of retentate chromatography for resolving analytes in a sample. The methods involve adsorbing the analytes to a substrate under a plurality of different selectively conditions, and detecting the analytes retained on the substrate by desorption spectrometry. The methods are useful in biology and medicine, including clinical diagnostics and drug discovery.
Abstract:
This invention provides methods of retentate chromatography for resolving analytes in a sample. The methods involve adsorbing the analytes to a substrate under a plurality of different selectively conditions, and detecting the analytes retained on the substrate by desorption spectrometry. The methods are useful in biology and medicine, including clinical diagnostics and drug discovery.
Abstract:
A method for analyzing total oil in place and fraction that is movable oil in a fine grain rock formation includes monitoring thermal extraction of hydrocarbon and non- hydrocarbon compounds from a sample of a subsurface formation by heating the sample. The heating has a selected initial temperature, and a temperature increase at a selected rate to a final temperature. The extracted hydrocarbon and non-hydrocarbon compounds are passed through a capillary column to a flame ionization detector. Types of hydrocarbon and non-hydrocarbon compounds and relative fractional amounts of each type thereof are determined from the sample by analyzing a chemical thermogram generated by the flame ionization detector.
Abstract:
The present invention relates to a column for performing analytical temperature rising elution fractionation (ATREF) characterized in that the packing of said column comprises elastic wires having a good elasticity and a good thermal conductivity. The present invention also relates to a device comprising the column according to the invention, a temperature controlling system for controlling the temperature of said column, a sample injector for injecting a polymer sample solution into said column, a pump for eluting the polymer fractions from said column and a detector for detecting eluting fractions of said sample solution. The present invention further relates to a method for performing ATREF analyses using the column according to the invention.
Abstract:
This invention provides methods of retentate chromatography for resolving analytes in a sample. The methods involve adsorbing the analytes to a substrate under a plurality of different selectivity conditions, and detecting the analytes retained on the substrate by desorption spectrometry. The methods are useful in biology and medicine, including clinical diagnostics and drug discovery.
Abstract:
A method for analyzing total oil in place and fraction that is movable oil in a fine grain rock formation includes monitoring thermal extraction of hydrocarbon and non- hydrocarbon compounds from a sample of a subsurface formation by heating the sample. The heating has a selected initial temperature, and a temperature increase at a selected rate to a final temperature. The extracted hydrocarbon and non-hydrocarbon compounds are passed through a capillary column to a flame ionization detector. Types of hydrocarbon and non-hydrocarbon compounds and relative fractional amounts of each type thereof are determined from the sample by analyzing a chemical thermogram generated by the flame ionization detector.
Abstract:
Procedimiento para el muestreo pasivo de contaminantes atmosféricos mediante el dispositivo VERAM. En la presente invención se describe un procedimiento versátil, fácil y de manejo rápido para la determinación de contaminantes orgánicos en aire mediante un dispositivo de muestreo pasivo formado por una membrana semipermeable plana de tipo tubo polimérico de tamaño variable rellena de una fase sólida o mezcla de fases sólidas (VERAM). La utilización de este dispositivo garantiza una determinación directa de los contaminantes adsorbidos mediante la aplicación de la técnica de desorción térmica seguida de la técnica de inyección de espacio de cabeza con cromatografía de gases y espectrometría de masas. (HS-GC- MS). Además, la presente invención describe el desarrollo de modelos matemáticos que correlacionen la cantidad absorbida por el muestreador con la concentración promedio del contaminante en el aire durante el periodo de muestreo.
Abstract:
An analytical method comprising performing a first fractionation of a polymer sample based on differences in crystallizability to provide a first set of sample fractions, performing a first analysis on the first set of sample fractions, performing a second fractionation of the first set of sample fractions to produce a second set of sample fractions, performing a second analysis on the second set of sample fractions, and synchronizing the first fractionation and second fractionation to provide about concurrent analysis of the polymer sample.
Abstract:
Carbon particulate concentration of diesel exhaust or other sampled gas is measured by collecting the particulate on a high efficiency filter (18) while measuring the amount of sampled gas passing through the filter (18). The filtered particulate is then heated in an oxygen rich environment (16) to oxidize carbon within the particulate to carbon dioxide. The amount of resulting carbon dioxide is measured with a closed measurement loop (30) to derive a corresponding measurement of the amount of filtered particulate. Particulate concentration is calculated by comparing the amount of carbon particulate with the measured amount of sampled gas passed through the filter. Filtered particulate can be heated incrementally to obtain a measurement of volatile carbon components within the particulate prior to the oxidation of the non-volatile carbon component. The filter (18) employed to collect the carbon particulate is of a high temperature resistant type making it reusable and can be either integral with or inserted into the oxidation chamber (16) of the instrument. Oxidation of the particulate inherently concurrently cleans the filter (18) for reuse. An upstream preseparator (15) can extend the life of the high efficiency filter (18). Particulate can also be collected for analysis by using an accelerating impaction nozzle (68) in conjunction with a heatable impaction plate (70).