A method for reducing the variability, as measured by relative standard deviation (RSD), of an analytical testing technique is provided. This improvement in RSD improves the confidence in the values obtained during field testing. The method includes incorporating a focusing agent into the sampling media, which permits providing sampling media such as thermal desorption tubes preloaded with the focusing agent.

A microscale collector and injector device comprises a microscale passive pre-concentrator (PP) and a microscale progressively-heated injector (PHI). The PP devices comprises first and second substrate portions, a first collection material, a PP heater, and an outlet. The first substrate portion defines an array of microscale diffusion channels. The first and second substrate portions cooperate to define a first compartment in fluid communication with the diffusion channels. The first collection material is disposed within the first compartment, at least partially surrounding the outlet. The PP heater is disposed in thermal communication with the second substrate portion. The PHI device comprises third and fourth substrate portions, a second collection material, and a plurality of PHI heaters. The third and fourth substrate portions cooperate to define a second compartment. The second collection material is disposed within the second compartment. The PHI heaters are disposed in thermal communication with the second compartment.

A microscale collector and injector device comprises a microscale passive pre-concentrator (PP) and a microscale progressively-heated injector (PHI). The PP devices comprises first and second substrate portions, a first collection material, a PP heater, and an outlet. The first substrate portion defines an array of microscale diffusion channels. The first and second substrate portions cooperate to define a first compartment in fluid communication with the diffusion channels. The first collection material is disposed within the first compartment, at least partially surrounding the outlet. The PP heater is disposed in thermal communication with the second substrate portion. The PHI device comprises third and fourth substrate portions, a second collection material, and a plurality of PHI heaters. The third and fourth substrate portions cooperate to define a second compartment. The second collection material is disposed within the second compartment. The PHI heaters are disposed in thermal communication with the second compartment.

A microfluidic device for separating a phase in a specimen has been described. This is based on a microfluidic trapping area, channels connected to it and integrated inputs and outputs connected onto the channels. An additional integrated input is provided which allows the flow in the device to be controlled and which may prevent leaking of the specimen and the phase.

The disclosed embodiments relate to the design of a preconcentrator system for preconcentrating air samples. This preconcentrator system includes a plurality of preconcentrators that preconcentrate the air samples prior to chemical analysis, and a delivery structure comprising a manifold that selectively routes a sample airflow to the plurality of concentrators so that the plurality of preconcentrators receive a sample airflow concurrently or individually.

The disclosed embodiments relate to the design of a preconcentrator system for preconcentrating air samples. This preconcentrator system includes a plurality of preconcentrators that preconcentrate the air samples prior to chemical analysis, and a delivery structure comprising a manifold that selectively routes a sample airflow to the plurality of concentrators so that the plurality of preconcentrators receive a sample airflow concurrently or individually.

An analysis method for a substance to be measured, including (a) introducing a sample into a flow channel having a bypass, flow channel and introducing the sample introduced into the bypass flow channel into a measuring device so as to measure signal intensity or concentration of a substance to be measured and/or a carrier in the sample; (b) introducing a sample that has not been introduced into the bypass flow channel into a column so as to adsorb the substance to be measured and/or the carrier; and (c) introducing an eluate into the column, eluting the substance to be measured and/or the carrier adsorbed on the column, and introducing the substance and/or the carrier into the measuring device so as to measure the signal intensity or concentration of the eluted substance to be measured and or the carrier.

The present invention is generally related to the analysis of chemical compositions of hydrocarbons and hydrocarbon blends. This method applies specifically to the problem of analyzing extremely complex hydrocarbon-containing mixtures when the number and diversity of molecules makes it impossible to realistically identify and quantify them individually in a reasonable timeframe and cost. The advantage to this method over prior art is the ability to separate and identify chemical constituents and solvent fractions based on their solvent-solubility characteristics, their high performance liquid chromatographic (HPLC) adsorption and desorption behaviors, and their interactions with stationary phases; and subsequently identify and quantify them at least partially using various combinations of non-destructive HPLC, destructive HPLC, and stand-alone detectors presently not routinely used for HPLC but reconfigured to obtain spectra on the fly. This analytical method is especially useful for, but not limited to, asphalt binders and asphalt binder blends, modified asphalts, asphalt modifiers, asphalt additives, polymer-modified asphalts, asphalts containing rejuvenators and softening agents, asphalts containing recycled products, aged asphalts, and air-blown asphalts, which may contain wide varieties of different types of additives and chemistries, and forensic applications, and environmental pollutant identification.

In a chromatography system, including within the system an extraction vessel which receives a mixture of mobile phase and co-solvent and provides a mixture of mobile phase and co-solvent with sample to a chromatography column to increase sample concentration within the mixture. In addition, adding a reservoir to the chromatography system to form an extraction-pressurization system, wherein the mixture with sample may be collected in the reservoir and may diffuse and equilibrate to an approximately uniform sample concentration before being provided to the chromatography column. Also in addition, providing a plurality of extraction-pressurization systems to allow near-simultaneous extraction of sample and loading of the column, or concurrent extraction and loading by the plurality of extraction-pressurization systems.

A system and method for purifying coenzyme Q.sub.10 are provided. The method includes: passing a CoQ.sub.10-containing crude product through a first chromatographic column to obtain a first CoQ.sub.10-containing intermediate product. The method further includes preparing, based on the first CoQ.sub.10-containing intermediate product, a second CoQ.sub.10-containing intermediate product. The method further includes passing the second CoQ.sub.10-containing intermediate product through a second chromatographic column to obtain a third CoQ.sub.10-containing intermediate product. The method further includes obtaining purified CoQ.sub.10 product by purifying the third CoQ.sub.10-containing intermediate product.