Track topics on Twitter Track topics that are important to you
The pressure drop and temperature drop on columns packed with 3- and 5-micron particles were measured using neat CO(2) at a flow rate of 5mL/min, at temperatures from 20°C to 100°C, and outlet pressures from 80 to 300bar. The density drop was calculated based on the temperature and pressure at the column inlet and outlet. The columns were suspended in a circulating air bath either bare or covered with foam insulation. The results show that the pressure drop depends on the outlet pressure, the operating temperature, and the thermal environment. A temperature drop was observed for all conditions studied. The temperature drop was relatively small (less than 3°C) for combinations of low temperature and high pressure. Larger temperature drops and density drops occurred at higher temperatures and low to moderate pressures. Covering the column with thermal insulation resulted in larger temperature drops and corresponding smaller density drops. At 20°C the temperature drop was never more than a few degrees. The largest temperature drops occurred for both columns when insulated at 80°C and 80bar, reaching a maximum value of 21°C for the 5-micron column, and 26°C for the 3-micron column. For an adiabatic column, the temperature drop depends on the pressure drop, the thermal expansion coefficient, and the density and the heat capacity of the mobile phase fluid, and can be described by a simple mathematical relationship. For a fixed operating temperature and outlet pressure, the temperature drop increases monotonically with the pressure drop.
Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, MN 55812, USA.
This article was published in the following journal.
Name: Journal of chromatography. A
A simple and sensitive method for the enantioselective determination of tebuconazole enantiomers in water and zebrafish has been established using supercritical fluid chromatography (SFC)-MS/MS. The e...
Essential oils and fatty acids of Descurainia sophia L. seed were obtained by supercritical CO2 extraction and steam distillation methods. The effect of different parameters such as pressure, temperat...
A continuous supercritical water oxidation reactor was designed and constructed to investigate the conversion of a feces simulant without the use of a co-fuel. The maximum reactor temperature and wast...
Atmospheric-pressure laser ionization mass spectrometry (APLI-MS) is a powerful method for the analysis of polycyclic aromatic hydrocarbon (PAH) molecules, which are ionized in a selective and highly ...
Supercritical fluid chromatography/tandem mass spectrometry (SFC-MS/MS) is an effective tool in separation science which uses the nontoxic CO2 fluid for better control of analyte retention. Also the t...
People with failed kidneys need an artificial kidney machine (called dialysis) to remove toxins and extra fluid from the body. Most patients receive dialysis treatments at a hospital three...
The purpose of the study is to evaluate dose-response, efficacy and safety of CP-690,550 eye drops in patients with dry eye disease.
Fluid therapy is one of the cornerstones of the treatment of organ failure. The investigators assume that fluid bolus will increase the delivery of oxygen to the cells and resolve the shoc...
Children who are critically ill often require large amounts of fluid during their acute illness. It has been shown in multiple studies that appropriate administration of fluid decreases mo...
There are many reasons that cause skin to breakdown. This study will only compare - pressure - pH - temperature with the use of slings and without the use of sling...
A CHROMATOGRAPHY method using supercritical fluid, usually carbon dioxide under very high pressure (around 73 atmospheres or 1070 psi at room temperature) as the mobile phase. Other solvents are sometimes added as modifiers. This is used both for analytical (SFC) and extraction (SFE) purposes.
Use of various chemical separation and extraction methods, such as SOLID PHASE EXTRACTION; CHROMATOGRAPHY; and SUPERCRITICAL FLUID EXTRACTION; to prepare samples for analytical measurement of components.
Manometric pressure of the CEREBROSPINAL FLUID as measured by lumbar, cerebroventricular, or cisternal puncture. Within the cranial cavity it is called INTRACRANIAL PRESSURE.
The administration of therapeutic agents drop by drop, as eye drops, ear drops, or nose drops. It is also administered into a body space or cavity through a catheter. It differs from irrigation in that the irrigate is removed within minutes, but the instillate is left in place.
The ratio of the density of a material to the density of some standard material, such as water or air, at a specified temperature.