The present invention suppresses an adverse effect caused when an additional gas such as water vapor is mixed in a sample gas or the like that is subjected to gas measurement. In an embodiment of the present invention, in gas measurement for analyzing sensor output signals obtained by alternately supplying a sample gas and a reference gas to a sensor element while alternately switching between the sample gas and the reference gas, the sample gas and the reference gas pass through a humidity equilibration device partitioned by a water vapor permeable membrane, and then are supplied to the sensor element. As a result, since both gases have substantially the same value of humidity at the time of being supplied to the sensor element, influences of water vapor are substantially cancelled out in signals output from the sensor element by the alternate supply of the sample gas and the reference gas.

A method and apparatus for analyzing solubility of asphaltenes of a hydrocarbon fluid sample involves a sequence of operations including: i) performing microfluidic mixing operations that form a mixture that includes the hydrocarbon fluid sample, a solvent that dissolves asphaltenes and a precipitant that precipitates asphaltenes; ii) using microfluidic processes that result in precipitation of asphaltenes from the mixture resulting from i); iii) performing microfluidic filtering operations that remove precipitated asphaltenes resulting from ii) and passes permeate; and iv) performing optical spectroscopy on the permeate resulting from iii). The operations of i)-iv) can be repeated over iterations that vary the amount of solvent relative to the precipitant in the mixture. These iterations can cause varying fractional precipitation of asphaltenes in each given iteration.

A method of analyzing, preferably by laser induced breakdown spectroscopy (LIBS), fluid samples (e.g. liquids, solutions, melts or slurries) that contain soluble and insoluble components of various elemental, molecular and biological components using a pre-characterized, preferably non-magnetic, membrane or plurality of membranes each having different characteristics, such as different porosities. The fluid sample is first deposited on the one or more membranes and the components to be analyzed are retained thereon through filtration or diffusion and then analyzed, such as with LIBS. Different components, such as different sized particles, are fixed on different membranes depending on the characteristics (e.g. pore size) of the corresponding membrane, which provides pre-sorting of the components before LIBS analysis.

Devices and methods for use in extraction procedures of analytes (organic and inorganic, including heavy metals) from matrices (e.g., complex matrices) in various fields (e.g., biological, clinical, chemical, environmental, toxicological, and forensic) are provided. The device can comprise a support structure acting as a rigid and stable support for extraction materials that can be inserted thereinto. The device can comprise a plurality of windows in the support structure through which the extraction materials can be exposed. The device can include two portions that can join together (e.g., using an interlocking system).

A sand column grouting filtration experimental device includes a sand column, a grout injection structure connected above the sand column and a grout exit structure connected below the sand column, the sand column comprises a plurality of connecting units; Four screws are provided around the sand column, and the four screws run through the grout injection structure and grout exit structure; A bottom plate is provided below the grout exit structure, a support plate one and a support plate two are provided between the bottom plate and the grout exit structure, and a sand column consolidation structure is provided between the support plate two and the support plate one. The experiment adopts a segmented combined sand column, in addition to ensuring the experimental results that can be obtained by the general sand column, segmented study of the interception and percolation effect of cement slurry in the sand column is implemented.

A method for separating plasma in a minute amount of a blood sample diluted with a blood dilution buffer is provided. When a blood dilution buffer is added to a minute amount of blood (about 20 to 100 L) so as to assay the biological blood components in the resulting diluted plasma, it is necessary to separately store and transfer the diluted blood cell component and the diluted plasma component. The present inventors found that it is possible to separate diluted plasma from diluted blood cells using a polymer gelling agent for plasma separation by means of putting a polymer gel for plasma separation in the container with a blood dilution buffer. In such case, diluted blood cells are transferred to the lower portion of the polymer gelling agent and dilute plasma is transferred to the upper portion of the same. Assay of the biological blood components using a minute amount of blood can be utilized for early detection of health status, diseases, and presymptomatic states. The method is advantageous in that it is not limited in terms of time or location for blood collection.

Devices and methods for use in extraction procedures of analytes (organic and inorganic, including heavy metals) from matrices (e.g., complex matrices) in various fields (e.g., biological, clinical, chemical, environmental, toxicological, and forensic) are provided. The device can comprise a support structure acting as a rigid and stable support for extraction materials that can be inserted thereinto. The device can comprise a plurality of windows in the support structure through which the extraction materials can be exposed. The device can include two portions that can join together (e.g., using an interlocking system).

The concentration of one or more gases in a surrounding fluid is measured using apparatus having a gas-permeable membrane separating an enclosed internal space within the apparatus from the surrounding fluid while allowing gases to diffuse from the surrounding fluid into the internal space. One or more sources sends infrared radiation along optical paths to one or more infrared detectors measuring intensity of radiation after absorption by gas(es) in the internal space and concentrations are determined from measured absorptions. The apparatus has more than one optical path through the internal space, enabling measurements of concentration over a greater range or enabling measurements of more than one gas present in very different concentrations or having very different infrared absorptivities.

A sand column grouting filtration experimental device includes a sand column, a grout injection structure connected above the sand column and a grout exit structure connected below the sand column, the sand column comprises a plurality of connecting units; Four screws are provided around the sand column, and the four screws run through the grout injection structure and grout exit structure; A bottom plate is provided below the grout exit structure, a support plate one and a support plate two are provided between the bottom plate and the grout exit structure, and a sand column consolidation structure is provided between the support plate two and the support plate one. An experiment that adopts a segmented combined sand column, in addition to ensuring the experimental results that can be obtained by the general sand column, segmented study of the interception and percolation effect of cement grout in the sand column is implemented.