Results 251 to 260 of about 40,598 (285)
Some of the next articles are maybe not open access.
Stress and strain during supercritical drying
Journal of Sol-Gel Science and Technology, 2018Supercritical drying avoids capillary forces, but damaging stresses can be generated during solvent exchange, pressurization, and depressurization. Each of those steps has been analyzed, so the duration of the process can be minimized without risk to the sample.
openaire +1 more source
Drying of silica aerogel with supercritical carbon dioxide
Journal of Non-Crystalline Solids, 1995For applications of monolithic silica aerogels, drying without cracking is an important issue. By extracting alcohol with supercritical CO2, crack-free aerogels can be obtained at 35°C and 85 bar. This opens the possibility for a large-scale aerogel drying process.
M.J. van Bommel, A.B. de Haan
openaire +1 more source
Stress development during supercritical drying
Journal of Non-Crystalline Solids, 1992Although supercritical drying eliminates the capillary stresses that cause damage during conventional drying, there are other sources of stress and strain that can destroy aerogels. During heating in the autoclave, expansion of the pore liquid causes dilatation of the gel network.
openaire +1 more source
Supercritical CO2 Drying of Red Bell Pepper
Food and Bioprocess Technology, 2020Supercritical CO2 food drying technique was investigated on red bell pepper with a lab-scale reactor equipped with CO2 recirculation. Box–Behnken design was used as experimental design to analyze the impact of temperature (313–333 K), pressure (10–14 MPa), CO2 flow rate (80–220 kg/h), and treatment time (6 and 16 h) on the final water activity.
Zambon A. +5 more
openaire +3 more sources
Preparation of silica-based aerogels by supercritical drying
Russian Journal of Physical Chemistry B, 2014A technique to improve the environmental friendliness of the preparation of aerogels has been proposed; an experimental setup for supercritical drying of aerogels has been designed. The results of the examination of the aerogels prepared by the proposed technique have been described.
N. V. Men’shutina +2 more
openaire +1 more source
Drying of Coals by Using Supercritical Carbon Dioxide
Industrial & Engineering Chemistry Research, 1998Drying of three types of coals (Witbank coal, Taiheiyo coal, and Brau coal) was carried out by using supercritical carbon dioxide at 313.2 K and 14.8 MPa. Further, other adsorbent samples (wet zeolite and wet activated carbon) were adopted for comparison.
Yoshio Iwai +4 more
openaire +1 more source
Supercritical drying with zeolite for the preparation of silica aerogels
Journal of Non-Crystalline Solids, 1998Adding zeolite during supercritical drying (SCD) process (methanol) when preparing silica aerogel was effective to make an aerogel with less shrinkage and without cracking. Silica aerogels prepared by adding zeolite had higher densities, despite less shrinkage, than those prepared without zeolite.
S. Yoda, S. Ohshima, F. Ikazaki
openaire +1 more source
Carotenoids microencapsulation by spray drying method and supercritical micronization
Food Research International, 2017Carotenoids are used as natural food colourants in the food industry. As unstable natural pigments they need protection. This protection can involve the microencapsulation process. There are numerous techniques that can be used for carotenoid protection, but two of them -spray drying and supercritical micronization - are currently the most commonly ...
openaire +2 more sources
Stress formation during heating in supercritical drying
Journal of Non-Crystalline Solids, 2001Silica aerogel preparation is analyzed and two different supercritical drying techniques, autoclave drying of the solvent and drying following carbon dioxide exchange of the solvent, are compared in terms of stress formation during the heating step. The model used is a partial differential equation that relates stress to thermal expansion and flow of ...
Betul Unlusu +2 more
openaire +1 more source
Building dry powder formulations using supercritical CO2 spray drying
Current Opinion in Green and Sustainable Chemistry, 2017This short review covers the most recent literature on the bottom-up assembling of composite dry powder formulations using supercritical carbon dioxide (scCO2)-based technologies for pulmonary delivery. Special attention is given to the integration of scCO2–assisted spray drying (SASD) with different technologies, namely living polymerization, layer-by-
openaire +1 more source