Search results for "eutectic"

Phase behaviour of deionized binary mixtures of charged colloidal spheres.

2009

We review recent work on the phase behaviour of binary charged sphere mixtures as a function of particle concentration and composition. Both size ratios and charge ratios are varied over a wide range. By contrast to hard spheres the long ranged Coulomb interaction stabilizes the crystal phase at low particle concentrations and shifts the occurrence of amorphous solids to particle concentrations considerably larger than the freezing concentration. Depending on size- and charge ratios we observe upper azeotrope, spindle, lower azeotrope and eutectic types of phase diagrams, all known well from metal systems. Most solids are of body centred cubic structure. Occasionally stoichiometric compound…

Eutectogel: materiali per il risanamento ambientale

2019

Eutectogels: Materials for Environmental Recovery

Polysaccharide-based supramolecular bicomponent eutectogels as sustainable antioxidant materials

2023

In this work, we obtained supramolecular gels in deep eutectic solvents (DES) from polysaccharides like chitosan and chitosan : cellulose composites. We thoroughly characterized our gels by determining the minimum gelation concentration, as well as their porosity and swelling. We also investigated their mechanical properties by rheology, and morphology by scanning electron measurements. These properties were mainly influenced by the number of hydrogen bond sites on the hydrogen bond donor, (HBD), while FTIR-ATR investigation suggested that, upon gelation, cholinium cations interpose between polysaccharide chains affecting interchain hydrogen bonding. Our gels also exhibited self-healing and…

Challenges in preparing for Environmental Technology Verification in a demonstration project: A case study of three innovative water treatment techno…

2022

The European Union's Environmental Technology Verification (ETV) program aims to foster innovative environmental technologies to reach the market and reassure potential users. This paper presents an investigation of using ETV for three technologies, being developed within the EU Zero Brine research and innovation project. The technologies were designed to recover high quality water, salts and minerals from brine solutions. The technologies in focus are the forward feed MED evaporator, the Multi Feed - Plug Flow Reactor Crystalliser and Eutectic Freeze Crystallization. The study sought to understand the challenges of the ETV process, the readiness and eligibility of technologies, and possibl…

Physical modelling of the melt flow during large-diameter silicon single crystal growth

2003

Abstract The reported investigations concern physical modelling of Czochralski growth of silicon large-diameter single crystals. InGaSn eutectic was used as a modelling liquid, employing actual criteria of the real process (Prandtl, Reynolds, Grashof numbers, etc.) and geometric similarity. A multi-channel measuring system was used to collect and process the temperature and flow velocity data. The investigations were focused on the study of heat transfer, in particular, the instability of the “cold zone” of the melt at the crystallization front.

SINTESI STEREOSELETTIVA IN IONO-EUTECTOGEL SUPRAMOLECOLARI

2021

Role of Diffusion in Superplasticity and Brittleness of Fine-Grained Binary Eutectics

2005

Mechanical properties of interphase boundaries (IB), stability of defects and microstructure in heavily deformed binary eutectics (Al-Sn, Zn-Sn, Pb-Sn, Cd-Sn, Bi-Sn) have been investigated at room temperature. Experiments were carried out on atomically clean surfaces of alloys and on bimetallic joints with clean interface. It has been shown that after severe deformation the phases are strengthened and relaxation processes occur mainly on the boundaries in all eutectics. For superplastic eutectics with low interphase boundary energy the intensive development of the diffusion – controlled processes of self- healing, sintering, segregation and enveloping were observed. These diffusion processe…

Highly recyclable surfactant-based supramolecular eutectogels for iodine removal

2022

In this work, we screened several surfactants for their ability to harden Eutectic Mixtures. We found cetyldiethanolamine-N-oxide as the best candidate, which was able to form eutectogel in four eutectic mixtures. Characterization of the gels obtained in terms of thermal stability, rheology and gelation kinetics, showed a prominent influence of the nature of the hydrogen bonding accepting and donating components for the first two parameter and the other one, respectively. Then, we assessed the eutectogels for their ability to adsorb I2, as a model for its radioactive nuclides, from apolar solvent solutions. The best performing gel allowed fast and thorough removal of I2, over a broad range …

Efficient extraction and preparative separation of four main isoflavonoids from Dalbergia odorifera T. Chen leaves by deep eutectic solvents-based ne…

2016

In this study, green and efficient deep eutectic solvent-based negative pressure cavitation-assisted extraction (DES-NPCE) followed by macroporous resin column chromatography was developed to extract and separate four main isoflavonoids, i.e. prunetin, tectorigenin, genistein and biochanin A from Dalbergia odorifera T. Chen leaves. The extraction procedure was optimized systematically by single-factor experiments and a Box-Behnken experimental design combined with response surface methodology. The maximum extraction yields of prunetin, tectorigenin, genistein and biochanin A reached 1.204, 1.057, 0.911 and 2.448mg/g dry weight, respectively. Moreover, the direct enrichment and separation of…