Samples are commonly prepared by heating them under vacuum or under a gas stream to remove impurities. The samples are then analyzed by measuring the volume of adsorbed gas, for example nitrogen, at specific pressures and at low temperatures, for example at 77K in liquid nitrogen.
The surface area is a measure of the exposed surface of a solid sample on a molecular scale. The BET theory is the most used model to determine the area but the results can also be obtained according to the Langmuir model.
To measure pore size by gas adsorption, isotherms are recorded in the range from low pressures to saturation pressure. The pressure range is determined by the pore size range to be measured: microporous materials are measured by isotherms in the pressure range 0.00001-0.1 torr, while mesoporous materials typically in a pressure range 1 - 760 torr.
The methods available for measuring micropore distribution include: Density Functional Theory (DFT), MP-Method, Dubinin Plots (Dubinin-Radushkevich D-R, Dubinin-Astakov D-A) and Horvath-Kawazoe (H-K). Methods available for Mesopores include: Barrett method, Joyner and Halenda (BJH) and Density Functional Theory (DFT).
Analysis of coffee particle characteristics, coffee creaming and bulk powder flow properties together with sensory analysis and high resolution SEM images can help you improve your coffee production process.
The unique potential of graphene, offering the theoretical strength of diamond together with the flexibility of plastic, finds application in a wide range of industries: from electronics to drug delivery. Graphene quality varies considerably depending on how the material is produced, so characterizing raw material and finished products is of fundamental importance.
The synthetic and natural HA differ in terms of physical microstructure, crystal size, and porosity, but chemical similarities to bone, in both forms, as well as biocompatibility, bioactivity and thermal stability in the body fluid pose Hydroxyapatite (HAp) as an attractive material for a wide range of applications in the biomedical field. Find out more!
Physical properties of excipients influence the stability, bioavailability, and processability of the dosage forms. Alfatestlab is equipped with all the analytical techniques necessary to support you in choosing the right excipient for your formulation: particle size, particle shape, flowability, density, surface area and much more!
Silica is one of the most complex and most abundant families of materials: sand, quartz, silica gels, precipitated silica, fumed silica, colloidal silica, mesoporous silica nanoparticles (MSNPs)... Any type of silica material finds specific applications and needs specific physical characterization!
Characterization of the API solid state is key to reduce possible future manufacturing or formulation issues and cut drug product development costs and time. Discover more!
Due to its high degree of microporosity, one gram of activated carbon can reach a surface area of 3,000 m2 as determined by gas adsorption. Discover more about its extraordinary properties!