A method of introducing a sample into a separation column includes introducing the sample into a trap column, isolating the trap column from ambient atmosphere and pressurizing the trap column to a first pressure while the trap column is isolated from ambient atmosphere, providing a fluid connection between the trap column and the separation column after pressurizing the trap column to the first pressure, supplying the sample from the trap column to the separation column.

LC techniques are disclosed. The LC technique includes providing a liquid chromatography system having a coated metallic fluid-contacting element, and transporting a fluid to contact the coated metallic fluid contacting element. Conditions for the transporting of the fluid are selected from the group consisting of the temperature of the fluid being greater than 150 degree Celsius, pressure urging the fluid being greater than 60 MPa, the fluid having a protein-containing analyte incompatible with one of titanium and polyether ether ketone, the fluid having a chelating agent incompatible with the one or both of the titanium or the polyether ether ketone.

LC techniques are disclosed. The LC technique includes providing a liquid chromatography system having a coated metallic fluid-contacting element, and transporting a fluid to contact the coated metallic fluid contacting element. Conditions for the transporting of the fluid are selected from the group consisting of the temperature of the fluid being greater than 150 degree Celsius, pressure urging the fluid being greater than 60 MPa, the fluid having a protein-containing analyte incompatible with one of titanium and polyether ether ketone, the fluid having a chelating agent incompatible with the one or both of the titanium or the polyether ether ketone.

A pump for high-pressure and/or nano-scale volumes permits identification of the internal pressure of the pump.

A pump for high-pressure and/or nano-scale volumes permits identification of the internal pressure of the pump.

A method for measuring a flow of a fluid in a tube includes heating the fluid in the tube with a heating element. A first signal is measured with a first temperature sensing element at a first location. A second signal is measured with a second temperature sensing element at a second location. At least one temperature signal is calculated based on the first signal and the second signal. The at least one temperature signal includes a difference temperature signal and a sum temperature signal. The difference temperature signal is calculated based on a difference between the second signal and the first signal. The sum temperature signal is calculated based on a sum of the second signal and the first signal. The flow is derived based on the difference temperature signal, the sum temperature signal, or a combination thereof.

A method for measuring a flow of a fluid in a tube includes heating the fluid in the tube with a heating element. A first signal is measured with a first temperature sensing element at a first location. A second signal is measured with a second temperature sensing element at a second location. At least one temperature signal is calculated based on the first signal and the second signal. The at least one temperature signal includes a difference temperature signal and a sum temperature signal. The difference temperature signal is calculated based on a difference between the second signal and the first signal. The sum temperature signal is calculated based on a sum of the second signal and the first signal. The flow is derived based on the difference temperature signal, the sum temperature signal, or a combination thereof.

The present invention relates to a dianhydride analysis method, which can reliably analyze a dianhydride having high reactivity and low solubility. In addition, the present invention can analyze the structure of impurities by separating the impurities on the basis of having a similar retention time in HPLC analysis, and can analyze the purity of the dianhydride with or without chromophores.

The present invention relates to a dianhydride analysis method, which can reliably analyze a dianhydride having high reactivity and low solubility. In addition, the present invention can analyze the structure of impurities by separating the impurities on the basis of having a similar retention time in HPLC analysis, and can analyze the purity of the dianhydride with or without chromophores.

Disclosed is a system for measuring mass transfer in a membrane and solutions. The system includes: a membrane module 10 including a feed solution reservoir 11 accommodating a feed solution f, a draw solution reservoir 13 accommodating a draw solution d whose osmotic concentration is higher than that of the feed solution f, and a holder 15 supporting a semipermeable membrane m arranged between the feed solution reservoir 11 and the draw solution reservoir 13 and whose performance is to be measured; a feed solution storage tank 20 storing the feed solution f; and a feed solution supply pump 30 supplying the feed solution f from the feed solution storage tank 20 to the feed solution reservoir 11 at a fixed flow rate corresponding to a water flux WF across the membrane m such that the water flux WF is maintained constant.