The invention provides separation media of substantially monodisperse populations of substantially spherical particles of polyarylketone polymers or of thio-analogues of such polymers, of selected sizes, and further provides containers, such as chromatographic columns and cartridges, containing substantially monodisperse populations of such particles.

The invention provides separation media of substantially monodisperse populations of substantially spherical particles of polyarylketone polymers or of thio-analogues of such polymers, of selected sizes, and further provides containers, such as chromatographic columns and cartridges, containing substantially monodisperse populations of such particles.

A quantitative analysis method for a monomer of a color filter (CF) photoresist (PR) binder for a thin film transistor-liquid crystal display (TFT-LCD), performs quantitative analysis on a monomer of a CF PR binder for a RFT-LCD by using a Py-GC/MS used for qualitative analysis.

A method for extracting an analyte from a solid sample is described. The sample is sealed in a porous membrane bag, which is sonicated in an organic solvent. An extract of the analyte forms in the bag and diffuses into the organic solvent. The organic solvent containing the extract may then be concentrated and analyzed for an analyte with gas chromatography-mass spectrometry. The method does not the use of a solid sorbent material, and does not require a step of centrifuging or filtering.

In a pretreatment method, in a first step, a sample is dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol to prepare a first solution. In a second step, an organic base that has a lower boiling point than that of HFIP is added to the first solution to prepare a second solution. In a third step, the second solution is heated to obtain a substance in which an anhydrous oxide structure in the sample has been decomposed. In a fourth step, chloroform is added to the second solution to prepare a third solution.

There are provided a urine testing apparatus and a urine testing method which can stabilize urine vitamins for several days and improve testing accuracy and convenience of a urine collection test of a subject. According to this urine testing apparatus, the inner wall surface of a urine collection storage container is coated with an aqueous citric acid solution or the like as a urine stabilizer. Alternatively, a dried or freeze-dried aqueous citric acid solution or the like as the urine stabilizer is stored in the urine collection storage container. On the other hand, according to the urine testing method of this invention, the aqueous citric acid solution or the like as the urine stabilizer is added to the collected urine sample, the vitamin concentration of at least 7 days after urine collection is stabilized to stabilize each urine vitamin for several days, thereby improving the convenience of the urine collection test of the subject. In particular, the urine concentrations of vitamins B can be stabilized to accurately test the nutrients lacking in the body of the subject.

There are provided a urine testing apparatus and a urine testing method which can stabilize urine vitamins for several days and improve testing accuracy and convenience of a urine collection test of a subject. According to this urine testing apparatus, the inner wall surface of a urine collection storage container is coated with an aqueous citric acid solution or the like as a urine stabilizer. Alternatively, a dried or freeze-dried aqueous citric acid solution or the like as the urine stabilizer is stored in the urine collection storage container. On the other hand, according to the urine testing method of this invention, the aqueous citric acid solution or the like as the urine stabilizer is added to the collected urine sample, the vitamin concentration of at least 7 days after urine collection is stabilized to stabilize each urine vitamin for several days, thereby improving the convenience of the urine collection test of the subject. In particular, the urine concentrations of vitamins B can be stabilized to accurately test the nutrients lacking in the body of the subject.

Described is a method for determining a dwell volume of a liquid chromatography system and a liquid chromatography system that can determined the system dwell volume. The method includes mixing a flow of a first solvent with a flow of a second solvent to form a solvent mixture. The flows of the first and second solvents are decreased and increased, respectively, to generate a gradient composition. A system pressure of the liquid chromatography system is measured to determine a pressure trace defined as the measured system pressure as a function of time. The dwell volume of the system is determined from a time delay determined between the gradient composition at the mixing location and the pressure trace. The method can be performed with a liquid chromatography system having a chromatographic column or a flow restrictor used in place of the chromatographic column.

Described is a method for determining a dwell volume of a liquid chromatography system and a liquid chromatography system that can determined the system dwell volume. The method includes mixing a flow of a first solvent with a flow of a second solvent to form a solvent mixture. The flows of the first and second solvents are decreased and increased, respectively, to generate a gradient composition. A system pressure of the liquid chromatography system is measured to determine a pressure trace defined as the measured system pressure as a function of time. The dwell volume of the system is determined from a time delay determined between the gradient composition at the mixing location and the pressure trace. The method can be performed with a liquid chromatography system having a chromatographic column or a flow restrictor used in place of the chromatographic column.

The present disclosure provides an automatic separation apparatus for four fractions of heavy oil and a separation method thereof, wherein the apparatus includes a solvent reservoir tank (1), a separation unit for four fractions of heavy oil (100) and a receiving apparatus (9). The separation unit for four fractions of heavy oil (100) includes: a filter disc (4) having one end in communication with the solvent reservoir tank (1), and the other end in communication with an inlet of a pre-column flow path switching valve (5); a chromatographic column (6) having an inlet in communication with an outlet of the pre-column flow path switching valve (5), and an outlet in communication with an inlet of a post-column flow path switching valve (8). The receiving apparatus is in communication with an outlet of the post-column flow path switching valve (8).