TiO2-HA composites obtained by combination of sol–gel synthesis and a supercritical CO2 drying process

This work explore the use of supercritical CO2 drying as alternative technique for the obtainment of pasteurized and high quality dried product. Several tests were conducted on animal, vegetable and fruit matrixes in order to investigate the effectiveness of SC-CO2 drying process at different process conditions. Design of experiment was performed to find the optimal process conditions for vegetable and fruit matrices, using the final water activity of the products as key indicator for the drying efficiency. The inactivation of naturally present microorganisms and inoculated pathogens demonstrated the capability of SC-CO2 drying process to assure a safe product. Moreover, retention of nutrients was compared with conventional drying methods. Results suggest that supercritical drying is a promising alternative technology for food drying. Keywords: supercritical drying; carbon dioxide; food drying; microbial inactivation

Download Full-text

Contamination Control in Supercritical CO2 Drying Process for Nano-Scale Memory Manufacturing

ECS Transactions ◽

10.1149/05806.0197ecst ◽

2013 ◽

Vol 58 (6) ◽

pp. 197-204

Author(s):

H. Hayashi ◽

H. Okuchi ◽

H. Tomita ◽

Y. Ono ◽

T. Nakamori ◽

...

Keyword(s):

Supercritical Co2 ◽

Drying Process ◽

Contamination Control ◽

Nano Scale ◽

Supercritical Co2 Drying

Download Full-text

Drying Behavior of Sol-Gel Derived A12O3 and Al2O3-Sic Composites

MRS Proceedings ◽

10.1557/proc-73-641 ◽

1986 ◽

Vol 73 ◽

Author(s):

R. H. Krabill ◽

D. E. Clark

Keyword(s):

Sol Gel ◽

Drying Process ◽

Critical Step ◽

Drying Behavior ◽

Sic Composites ◽

Sol Gel Synthesis ◽

Gel Drying

ABSTRACTGel drying is a critical step in the sol-gel synthesis of Al2O3 and Al2O3-SiC composites. Problems exist during the drying stage that affect the monolithic properties of the sintered products. Classical drying theory was applied to the drying behavior of Al2O3 and Al2O3-SiC composites in an effort to optimize the drying process and understand the controlling mechanisms.

Download Full-text

Aerogels: II. Applications in catalysis

Hemijska industrija ◽

10.2298/hemind0212514o ◽

2002 ◽

Vol 56 (12) ◽

pp. 514-520

Author(s):

Aleksandar Orlovic ◽

Djordje Janackovic ◽

Ljiljana Kostic-Gvozdenovic ◽

Dejan Skala

Keyword(s):

Molecular Level ◽

Sol Gel ◽

Supercritical Drying ◽

Structural Features ◽

Metastable Phases ◽

Drying Process ◽

Sol Gel Process ◽

One Step ◽

Sol Gel Synthesis

Sol-gel synthesis, and the resulting materials (xerogels and aerogels) are finding increasing application in the synthesis of catalysts, due to their unique characteristics. The most important features of the sol-gel process are: the ability to achieve homogeneity at the molecular level, the introduction of several species in only one step and the ability to stabilize metastable phases. The supercritical drying process produces aerogels with structural features quite different to conventional materials. Some of these characteristics of aerogels can make them very effective catalysts.

Download Full-text

Microbial inactivation efficiency of supercritical CO2 drying process

Drying Technology ◽

10.1080/07373937.2018.1433683 ◽

2018 ◽

Vol 36 (16) ◽

pp. 2016-2021 ◽

Cited By ~ 8

Author(s):

Alessandro Zambon ◽

Filippo Michelino ◽

Siméon Bourdoux ◽

Frank Devlieghere ◽

Stefania Sut ◽

...

Keyword(s):

Supercritical Co2 ◽

Microbial Inactivation ◽

Drying Process ◽

Supercritical Co2 Drying ◽

Inactivation Efficiency

Download Full-text

Editorial on Special Issues “Aerogels” and “Aerogels 2018”

Gels ◽

10.3390/gels6030019 ◽

2020 ◽

Vol 6 (3) ◽

pp. 19

Author(s):

Françoise Quignard ◽

Nathalie Tanchoux

Keyword(s):

Porous Structure ◽

Supercritical Co2 ◽

Freeze Drying ◽

Drying Process ◽

Gel Structure ◽

Supercritical Co2 Drying

Aerogels can be defined as ultralight materials with a 3D porous structure, similar to their parent wet gels, where the solvent has been replaced by a gas without a collapse of the gel structure, thanks to the drying process used (supercritical CO2 drying, freeze drying, etc [...]

Download Full-text

Contamination Control in Supercritical CO2 Drying Process for Nano-Scale Memory Manufacturing

ECS Meeting Abstracts ◽

10.1149/ma2013-02/30/2118 ◽

2013 ◽

Keyword(s):

Supercritical Co2 ◽

Drying Process ◽

Contamination Control ◽

Nano Scale ◽

Supercritical Co2 Drying

Download Full-text

Acemannan Gels and Aerogels

Polymers ◽

10.3390/polym11020330 ◽

2019 ◽

Vol 11 (2) ◽

pp. 330

Author(s):

Daniel Miramon-Ortíz ◽

Waldo Argüelles-Monal ◽

Elizabeth Carvajal-Millan ◽

Yolanda López-Franco ◽

Francisco Goycoolea ◽

...

Keyword(s):

Supercritical Co2 ◽

Chemical Structure ◽

Spectroscopic Analysis ◽

Drying Process ◽

Solvent Treatment ◽

Surface Areas ◽

Infrared Spectroscopic Analysis ◽

Bioactive Properties ◽

Supercritical Co2 Drying ◽

Drying Technology

The procedures to obtain two types of acemannan (AC) physical gels and their respective aerogels are reported. The gelation was induced by the diffusion of an alkali or a non-solvent, then supercritical CO2 drying technology was used to remove the solvent out and generate the AC aerogels. Fourier-transform infrared spectroscopic analysis indicated that alkali diffusion produced extensive AC deacetylation. Conversely, the non-solvent treatment did not affect the chemical structure of AC. Both types of gels showed syneresis and the drying process induced further volume reduction. Both aerogels were mesoporous nanostructured materials with pore sizes up to 6.4 nm and specific surface areas over 370 m2/g. The AC physical gels and aerogels enable numerous possibilities of applications, joining the unique features of these materials with the functional and bioactive properties of the AC.

Download Full-text

Inorganic-organic Hybrid Materials for Real 3-D Sub-νm Lithography

MRS Proceedings ◽

10.1557/proc-780-y4.12 ◽

2003 ◽

Vol 780 ◽

Cited By ~ 1

Author(s):

R. Houbertz ◽

J. Schulz ◽

L. Fröhlich ◽

G. Domann ◽

M. Popall ◽

...

Keyword(s):

Femtosecond Laser ◽

Sol Gel ◽

Laser Pulses ◽

Femtosecond Laser Pulses ◽

Hybrid Polymer ◽

Organic Hybrid ◽

Two Photon ◽

Applied Technology ◽

Scale Structures ◽

Sol Gel Synthesis

AbstractReal 3-D sub-νm lithography was performed with two-photon polymerization (2PP) using inorganic-organic hybrid polymer (ORMOCER®) resins. The hybrid polymers were synthesized by hydrolysis/polycondensation reactions (modified sol-gel synthesis) which allows one to tailor their material properties towards the respective applications, i.e., dielectrics, optics or passivation. Due to their photosensitive organic functionalities, ORMOCER®s can be patterned by conventional photo-lithography as well as by femtosecond laser pulses at 780 nm. This results in polymerized (solid) structures where the non-polymerized parts can be removed by conventional developers.ORMOCER® structures as small as 200 nm or even below were generated by 2PP of the resins using femtosecond laser pulses. It is demonstrated that ORMOCER®s have the potential to be used in components or devices built up by nm-scale structures such as, e.g., photonic crystals. Aspects of the materials in conjunction to the applied technology are discussed.

Download Full-text