Fluorous Catalysis under Homogeneous Conditions without Fluorous Solvents:  A “Greener” Catalyst Recycling Protocol Based upon Temperature-Dependent Solubilities and Liquid/Solid Phase Separation

2003 ◽  
Vol 125 (19) ◽  
pp. 5861-5872 ◽  
Author(s):  
Marc Wende ◽  
J. A. Gladysz
Keyword(s):  
Phase Separation ◽  
Solid Phase ◽  
Temperature Dependent ◽  
Catalyst Recycling

scholarly journals Solid-Phase “Self-Hydrolysis” of [Zn(NH3)4MoO4@2H2O] Involving Enclathrated Water—An Easy Route to a Layered Basic Ammonium Zinc Molybdate Coordination Polymer

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4022
Author(s):  
Kende Attila Béres ◽  
István E. Sajó ◽  
György Lendvay ◽  
László Trif ◽  
Vladimir M. Petruševski ◽  
...  
Keyword(s):  
Coordination Polymer ◽  
Solid Phase ◽  
Water Molecules ◽  
Temperature Dependent ◽  
Dynamic Interactions ◽  
Ammonia Release ◽  
Successive Substitution ◽  
Red Dye ◽  
Hydrolysis Of ◽  
Zinc Molybdate

An aerial humidity-induced solid-phase hydrolytic transformation of the [Zn(NH3)4]MoO4@2H2O (compound 1@2H2O) with the formation of [(NH4)xH(1−x)Zn(OH)(MoO4)]n (x = 0.92–0.94) coordination polymer (formally NH4Zn(OH)MoO4, compound 2) is described. Based on the isostructural relationship, the powder XRD indicates that the crystal lattice of compound 1@2H2O contains a hydrogen-bonded network of tetraamminezinc (2+) and molybdate (2−) ions, and there are cavities (O4N4(μ-H12) cube) occupied by the two water molecules, which stabilize the crystal structure. Several observations indicate that the water molecules have no fixed positions in the lattice voids; instead, the cavity provides a neighborhood similar to those in clathrates. The @ symbol in the notation is intended to emphasize that the H2O in this compound is enclathrated rather than being water of crystallization. Yet, signs of temperature-dependent dynamic interactions with the wall of the cages can be detected, and 1@2H2O easily releases its water content even on standing and yields compound 2. Surprisingly, hydrolysis products of 1 were observed even in the absence of aerial humidity, which suggests a unique solid-phase quasi-intramolecular hydrolysis. A mechanism involving successive substitution of the ammonia ligands by water molecules and ammonia release is proposed. An ESR study of the Cu-doped compound 2 (2#dotCu) showed that this complex consists of two different Cu2+(Zn2+) environments in the polymeric structure. Thermal decomposition of compounds 1 and 2 results in ZnMoO4 with similar specific surface area and morphology. The ZnMoO4 samples prepared from compounds 1 and 2 and compound 2 in itself are active photocatalysts in the degradation of Congo Red dye. IR, Raman, and UV studies on compounds 1@2H2O and 2 are discussed in detail.

scholarly journals Prion-Like Proteins in Phase Separation and Their Link to Disease

Biomolecules ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1014
Author(s):  
Macy L. Sprunger ◽  
Meredith E. Jackrel
Keyword(s):  
Protein Folding ◽  
Phase Transitions ◽  
Phase Separation ◽  
Liquid Phase ◽  
Protein Misfolding ◽  
Solid Phase ◽  
Liquid Phase Separation ◽  
Therapeutic Approaches ◽  
Important Physiological Process ◽  
Liquid Liquid Phase Separation

Aberrant protein folding underpins many neurodegenerative diseases as well as certain myopathies and cancers. Protein misfolding can be driven by the presence of distinctive prion and prion-like regions within certain proteins. These prion and prion-like regions have also been found to drive liquid-liquid phase separation. Liquid-liquid phase separation is thought to be an important physiological process, but one that is prone to malfunction. Thus, aberrant liquid-to-solid phase transitions may drive protein aggregation and fibrillization, which could give rise to pathological inclusions. Here, we review prions and prion-like proteins, their roles in phase separation and disease, as well as potential therapeutic approaches to counter aberrant phase transitions.

Epitaxial Growth of SixGe1−x Films on Si by Solid Phase Epitaxy.

1984 ◽  
Vol 37 ◽  
Author(s):  
C. S. Pai ◽  
S. S. Lau
Keyword(s):  
Phase Separation ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Ohmic Contacts ◽  
Solid Phase ◽  
Metal Layer ◽  
Alloyed Layer ◽  
Quaternary Compounds ◽  
Amorphous Si ◽  
Ion Backscattering

AbstractIt has been demonstrated in the literature that amorphous Si (or Ge) can be transported across a metal layer and grown epitaxially on Si(Ge) single crystal substrates in the solid phase. The objective of this study is to investigate if amorphous SixGe1−x mixtures can be transported uniformly across a medium and grown epitaxially on single crystal substrates without phase separation. The samples were prepared by e-beam evaporation of thin Pd films onto Si<100> substrates, followed by co-evaporation of SixGe1−x alloyed films (0<x<1) without breaking vacuum. The samples were anneaie in vacuum at 300°C to form a Pd silicide-germanide layer at the interface, then at 500°C for transport of the alloyed layer across the Pd silicide-germanide layer and subsequent epitaxial growth on Si substrate. The samples were investigated by x-ray diffraction and by MeV ion backscattering and channeling. The results show the alloyed film transports uniformly with no phase separation detected. The channeling result shows the grown alloyed layer is epitaxial with some Pd trapped in the layer. This simple technique is potentially useful for forming lattice-matched non-alloyed ohmic contacts on III–V ternary and quaternary compounds.

Modelling Semi-Solid Behaviour and Brittle Temperature Range

2019 ◽  
Vol 285 ◽  
pp. 361-366 ◽  
Author(s):  
Khalil Traidi ◽  
Véronique Favier ◽  
Philippe Lestriez ◽  
Karl Debray ◽  
Laurent Langlois ◽  
...  
Keyword(s):  
Solid State ◽  
Material Properties ◽  
Solid Phase ◽  
Thermal Conditions ◽  
Tensile Tests ◽  
Internal Variable ◽  
Temperature Dependent ◽  
Brittle Transition ◽  
Semi Solid ◽  
First Time

In this paper, a new elastic viscoplastic micromechanical modelling is proposed to represent the semi-solid behaviour and predict the ductile-brittle transition of the C38LTT near the solidus. It is based on a viscoplastic modelling previously presented in [1]. The originality of the new model comes from three main enhancements: the transition between the solid state and the semi-solid state was included meaning that the material properties were taken temperature-dependent, the elastic properties was taken into account similarly as [2] and the evolution of the internal variable describing the degree of agglomeration of the solid phase was enhanced. The model was implemented in the commercial software FORGE©. Tensile tests representing the experimental thermal conditions and obtained using a GLEEBLE© machine were simulated. The comparison of the predicted and experimental results shows that, for the first time to our knowledge, the three steps of the load-displacement response and ductile-brittle transition were successfully described.

The effect of phase separation on the temperature dependent magnetoresistance in perovskite oxide heterojunction

2008 ◽  
Vol 93 (16) ◽  
pp. 162106 ◽  
Author(s):  
Chun-lian Hu ◽  
Kui-juan Jin ◽  
Peng Han ◽  
Hui-bin Lu ◽  
Leng Liao ◽  
...  
Keyword(s):  
Phase Separation ◽  
Perovskite Oxide ◽  
Temperature Dependent

"Double-W-shaped" temperature dependence of emission linewidth in an InGaN/GaN multiple quantum well structure with intense phase separation

2020 ◽  
Vol 10 (1) ◽  
pp. 140-144
Author(s):  
Changfu Li ◽  
Mingsheng Xu ◽  
Ziwu Ji ◽  
Kaiju Shi ◽  
Hongbin Li ◽  
...  
Keyword(s):  
Phase Separation ◽  
Temperature Dependence ◽  
Multiple Quantum Well ◽  
Excitation Power ◽  
Multiple Quantum ◽  
Temperature Dependent ◽  
Two Phase ◽  
Phase Structures ◽  
Temperature Dependences ◽  
Lower Excitation

The temperature dependence of the spectra of photoluminescence (PL) from a blue InGaN/GaN multiplequantum-well (MQW) structure is investigated at lower excitation power. Two emission peaks, related to InGaN and assigned to In-rich quasi-quantum dots (QDs) and InGaN-matrix in the full PL spectrum, were observed. Upon increasing the temperature, both PL peak linewidths exhibited "double-W-shaped" (narrowing–broadening–narrowing–broadening–narrowing–broadening) temperature dependence. Combined with the observed features of the temperature dependences of the PL intensities, the temperature-dependent behaviors in this case can be interpreted as the relaxation and thermalization of carriers inside respective phase structures and the transfer of carriers between two phase structures, because of the strong phase separation and significant component fluctuation in the InGaN well layers.

Temperature dependent phase separation in the Emery model

1992 ◽  
Vol T45 ◽  
pp. 88-90 ◽  
Author(s):  
K Dichtel ◽  
J Carstensen
Keyword(s):  
Phase Separation ◽  
Temperature Dependent ◽  
Emery Model
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