A plug unit configured for use in high performance liquid chromatography is described. The plug unit comprises a capillary comprising a capillary distal face; a sealing element, wherein at least a portion of the sealing element is located distal from the capillary distal face; and a biasing element configured to bias the capillary towards the sealing element.

Described is a radial flow column for conveying a liquid product through an adsorber material, more particularly for radial flow chromatography, having a housing and, arranged therein, an inner and an outer screen, each of which surrounds a longitudinal axis of the housing and between which a radial intermediate space for receiving the adsorber material is formed. The end-face end regions of the inner and outer screen are sealed with respect to the housing in order to convey the product radially through the screens and the adsorber material. Because the radial flow column comprises ring seals for radially sealing the end-face end regions and the ring seals with corresponding sealing faces permit an axial play of the screens in the housing, production tolerances of the screens with respect to one another and in relation to the housing, and longitudinal fluctuations of the screens, can be compensated in a material-preserving manner.

Disclosed are chromatography systems employing a releasable coupling (100) for holding a fluid tubing to a spigot, the coupling comprising: a cylindrical inner component (110) for accepting a fluid tubing (30), said inner component including a resiliently deflectable portion (118) arranged to urge an outer surface of the tubing toward a spigot; and a cylindrical collar (130) having and internal through-aperture (132) for slideably accepting the inner component, the aperture and resilient portion having complementary surface formations which in a first position of the collar mounted to the inner component provide for said resilient deflection in use, and which in a second different position do not cause said deflection, the coupling being characterized in that the collar comprises a collar flange (134) extending outwardly away from the aperture of a size allowing manual manipulation of the collar between the first and second positions. Chromatography systems employing said couplings is disclosed also.

The disclosed system and method improve measurement of trace volatile chemicals, such as by Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GCMS). A first trapping system can include a plurality of capillary columns in series and a focusing column fluidly coupled to a first detector. The first trapping system can retain and separate compounds in a sample, including C3 hydrocarbons and compounds heavier than C3 hydrocarbons (e.g., up to C12 hydrocarbons, or compounds having a boiling point around 250° C.), and can transfer the compounds from the focusing column to the first detector. A second trapping system can receive compounds that the first trapping system does not retain, and can include a packed trap and two columns. The second trapping system can remove water from the sample and can separate and detect compounds including C2 hydrocarbons and Formaldehyde.

Presented herein is a new concept of uniformly spin coating a flat surface with a stationary phase and creating a gas chromatography column by pressing a grooved lid, with micro-stamped ridges, down onto the coated substrate. The lids are molded out of commercially available rigid materials including epoxies so that when pressed onto a flat surface it will create an air tight seal. The epoxy material is rendered inert by a thin layer of gold.

Disclosed is a device for evaluating damage of fracturing fluid to reservoir and operation method thereof, the device includes a liquid storage tank, a suction tube, a chromatography device, a bracket, a receiving container and a height adjuster; the disclosure has the following beneficial effects: since different liquids pass through the porous medium at different time and speed and the silica gel particles will not expand when immersed in the liquid, a porous structure is formed by placing silica gel particles of different sizes to simulate the pore-throat structure of unconventional oil and gas reservoirs, hence removing the influence of fracturing fluid on the hydration and expansion damage of the reservoir matrix, by testing the time and flow rate of different fracturing fluids flowing through the silica gel pores, the degree of damage caused by fracturing fluids to unconventional oil and gas reservoirs is evaluated.

A 3D gas chromatography (GC) column development is possible by assembly of two parts each being substrates formed by gas tight materials. One part may be a silicon substrate with a snake shaped flow channel structure and the other part may be a glass plate. Both are coated with a column packing comprising polubutadiene, which is also able to glue or bond both parts together, thereby sealing the flow channel, thus forming a GC column. The column packaging can be composed in all kinds of polarity from very hydrophobic till very hydrophilic. In this way the column packing can be tuned on resolution for particular molecules which are interesting to detect, e.g. Octane. The invention is advantageous for micro GC columns.

A gas chromatography device for peak focusing of one or more target analytes is provided that include a chromatographic column with an inlet and an outlet. A stationary phase is deposited inside the chromatographic column and has a positive thickness gradient. The stationary phase extends from the inlet to the outlet and has a first thickness at the inlet of the chromatographic column and a second thickness at the outlet of the chromatographic column. The second thickness is at least about 10% greater than the first thickness. Methods of peak focusing in a gas chromatography device, method of verifying peak focusing in a gas chromatography device and creating a gas chromatography device having a chromatographic column with a positive thickness gradient are also provided.

Disclosed is a device for evaluating damage of fracturing fluid to reservoir and operation method thereof, the device includes a liquid storage tank, a suction tube, a chromatography device, a bracket, a receiving container and a height adjuster; the disclosure has the following beneficial effects: since different liquids pass through the porous medium at different time and speed and the silica gel particles will not expand when immersed in the liquid, a porous structure is formed by placing silica gel particles of different sizes to simulate the pore-throat structure of unconventional oil and gas reservoirs, hence removing the influence of fracturing fluid on the hydration and expansion damage of the reservoir matrix, by testing the time and flow rate of different fracturing fluids flowing through the silica gel pores, the degree of damage caused by fracturing fluids to unconventional oil and gas reservoirs is evaluated.

A fitting includes a screw portion that is rotatable around an axis extending in one direction, an operating portion that applies a torque around the axis to the screw portion, and a rotation auxiliary member that is configured to be engageable with the operating portion. A slot extending from a first end to a second end is provided in the rotation auxiliary member, and also a first projection that protrudes outward is provided on the rotation auxiliary member. A positional relationship of the first projection is set such that an engaging force between the rotation auxiliary member and the operating portion is increased due to a change in width of the slot in a case where a force is applied to the first projection in the first rotation direction with the rotation auxiliary member engaging with the operating portion.