The chemical and physical properties of tetravalent lanthanides: Pr, Nd, Tb, and Dy

2020 ◽  
Vol 49 (45) ◽  
pp. 15945-15987 ◽  
Author(s):  
Thaige P. Gompa ◽  
Arun Ramanathan ◽  
Natalie T. Rice ◽  
Henry S. La Pierre
Keyword(s):  
Physical Properties ◽  
Gas Phase ◽  
Molecular Complexes ◽  
Descriptive Chemistry ◽  
Phase Solution

The thermochemistry, descriptive chemistry, spectroscopy, and physical properties of the tetravalent lanthanides (Pr, Nd, Tb and Dy) in extended phases, gas phase, solution, and as isolable molecular complexes are presented.

Separation Features in Hydrocarbon Media at Thermobaric Regimes of Petroleum Preparation Devices Functioning

2017 ◽  
Vol 743 ◽  
pp. 373-377
Author(s):  
Eugenii V. Nikolayev ◽  
Sergey N. Kharlamov ◽  
Laura Meucci
Keyword(s):  
Physical Properties ◽  
Gas Phase ◽  
Transport Processes ◽  
Gas Mixture ◽  
Multicomponent Systems ◽  
Composition Change ◽  
Separation Processes ◽  
Exchange Processes ◽  
Temperature And Pressure ◽  
Hydrocarbon Media

In this paper the features of separation processes modelling are analyzed in hydrocarbonic media within the limits of thermodynamics of equilibrium states. Approaches to calculation of phase equilibrium in multicomponent systems are discussed. Regularities and peculiarities of composition change of gas mixture depending on the temperature and pressure are studied. It has been established that there are specific conditions of non-monotonic change of composition with extremums for some separation regimes that significantly influences the physical properties and intensity of exchange processes at the heat-and mass transfer in multicomponent hydrocarbon media. In addition, the details of the behavior of gas phase with changing its thermal and physical properties have been discussed. Also, the calculated distributions of Prandtl, Schmidt and Lewis-Semenov numbers essentially influencing on the intensity of transport processes are considered.

ChemInform Abstract: 1,2-Diphenylcycloalkenes: Electronic and Geometric Structures in the Gas Phase, Solution, and Solid State.

ChemInform ◽  
1988 ◽  
Vol 19 (45) ◽  
Author(s):  
G. HOHLNEICHER ◽  
M. MUELLER ◽  
M. DEMMER ◽  
J. LEX ◽  
J. H. PENN ◽  
...  
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Geometric Structures ◽  
Phase Solution ◽  
Electronic And Geometric Structures

Processing-Microstructure-Tensile Property of Vapor Grown Carbon Fiber Reinforced Carbon Composite

1995 ◽  
Vol 383 ◽  
Author(s):  
Jyh-Ming Ting
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Carbon Fiber ◽  
Physical Properties ◽  
Tensile Properties ◽  
Gas Phase ◽  
Thermal Management ◽  
Carbon Fibers ◽  
Carbon Composite ◽  
Carbon Composites

ABSTRACTIn contrast to the form in which other carbon fibers are produced, vapor grown carbon fiber (VGCF) is produced from gas phase precursors in the form of individual fibers of discrete lengths. VGCF can be harvested as a mat of semi-aligned, semicontinuous fibers, with occasional fiber branching and curling. The use of VGCF mats as reinforcement result in composites which exhibit unique microstructure and physical properties that are not observed in other types of carbon composites. This paper describes the processing of VGCF mats reinforced carbon composites, and its unique microstructure and properties. Utilization of fiber tensile properties, as well as thermal conductivity, in the composites is discussed. Comparison of experimental results from various VGCF composites to theory indicates that mechanical properties are more strongly affected by characteristics of VGCF mat than are thermal conductivity. The implications of this relationship favors applications for thermal management where structural demands are less stringent.

Physical Properties of Germanium Telluride Crystals Grown from Gas Phase

1984 ◽  
Vol 84 (2) ◽  
pp. K173-K176 ◽  
Author(s):  
N. N. Koren ◽  
V. I. Levchenko ◽  
V. V. Dikareva ◽  
A. V. Kazushchik
Keyword(s):  
Physical Properties ◽  
Gas Phase ◽  
Germanium Telluride

scholarly journals A young star-forming galaxy at z = 3.5 with an extended Lyman α halo seen with MUSE

2015 ◽  
Vol 11 (A29B) ◽  
pp. 820-821
Author(s):  
Vera Patrício ◽  
Johan Richard ◽  
Anne Verhamme ◽  
Keyword(s):  
Physical Properties ◽  
Gas Phase ◽  
Surface Brightness ◽  
Spatial Information ◽  
Young Star ◽  
Star Forming ◽  
Uv Emission ◽  
Low Metallicity ◽  
Reasonable Description ◽  
First Time

AbstractWe present MUSE observations of a typical (M⋆ = 6 × 109M⊙) young lensed galaxy at z=3.5, for which we obtain 2D resolved spatial information of Ly α and, for the first time, of C iii] emission. We also derive important physical properties from several UV emission and absorption lines, rarely seen at these redshifts. Stellar and gas-phase metallicities point towards a low metallicity object. We model the Ly α line and surface brightness profile using a radiative transfer code in an expanding gas shell, finding that this model provides a reasonable description of both observables.

scholarly journals Structural diversity in the host–guest complexes of the antifolate pemetrexed with native cyclodextrins: gas phase, solution and solid state studies

2017 ◽  
Vol 13 ◽  
pp. 2252-2263 ◽  
Author(s):  
Magdalena Ceborska ◽  
Magdalena Zimnicka ◽  
Aneta Aniela Kowalska ◽  
Kajetan Dąbrowa ◽  
Barbara Repeć
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Structural Diversity ◽  
2D Nmr ◽  
Association Constants ◽  
Inclusion Type ◽  
Guest Molecules ◽  
Type Complex ◽  
The Stability ◽  
Phase Solution

The complexation of the antifolate pemetrexed (PTX) with native cyclodextrins was studied. This process, along with the findings gathered for the structurally related folic acid was treated as a model for exploiting host–guest interactions of this class of guest molecules in the gas phase, in solution and in the solid state. Mass spectrometry was employed for the investigation of the architecture and relative gas-phase stabilities of these supramolecular complexes. The mode of complexation was further tracked by 1D and 2D NMR proving the formation of the exclusion-type complex with α-CD and pseudorotaxane inclusion-type complexes with β-, and γ-CDs. UV–vis titrations at pH 7.4 gave association constants for the obtained complexes. The stability of the complexes increases in the series: α-CD/PTX < γ-CD/PTX << β-CD/PTX. The association of PTX with a monomer cyclodextrin equivalent – methyl α-D-glucopyranoside – was investigated for a deeper understanding of the type of host–guest interactions. Solid state studies of PTX/CDs were performed using FTIR–ATR and Raman spectroscopy techniques.

scholarly journals Actual Symmetry of Symmetric Molecular Adducts in the Gas Phase, Solution and in the Solid State

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 756
Author(s):  
Ilya G. Shenderovich
Keyword(s):  
Gas Phase ◽  
Noncovalent Interactions ◽  
Experimental Methods ◽  
Model Systems ◽  
Symmetric Structure ◽  
Phase Solution ◽  
Water Hydrogen ◽  
Different Time Scales ◽  
Steric Hindrances ◽  
Molecular Adducts

This review discusses molecular adducts, whose composition allows a symmetric structure. Such adducts are popular model systems, as they are useful for analyzing the effect of structure on the property selected for study since they allow one to reduce the number of parameters. The main objectives of this discussion are to evaluate the influence of the surroundings on the symmetry of these adducts, steric hindrances within the adducts, competition between different noncovalent interactions responsible for stabilizing the adducts, and experimental methods that can be used to study the symmetry at different time scales. This review considers the following central binding units: hydrogen (proton), halogen (anion), metal (cation), water (hydrogen peroxide).

scholarly journals PROTON TRANSFER IN PHOSPHORUS-CONTAINING ACID–N,N-DIMETHYLFORMAMIDE SYSTEM WITH GLANCE OF ENVIRONMENT

2018 ◽  
Vol 59 (6) ◽  
pp. 37
Author(s):  
Lyubov P. Safonova ◽  
Irina V. Fedorova ◽  
Michael A. Krestyaninov
Keyword(s):  
Proton Transfer ◽  
Solvent Effect ◽  
Gas Phase ◽  
Energy Barrier ◽  
Continuum Model ◽  
Energy Surface ◽  
Molecular Complexes ◽  
Transfer Processes ◽  
Polarized Continuum Model ◽  
Phosphorus Containing

Proton transfer processes in the molecular and ion-molecular complexes of phosphorus acids (phosphoric H3PO4, phosphorous H3PO3, methylphosphonic СН3Н2РО3) with N,N-dimethylformamide (DMF) was studied. The potential energy surface (PES) for proton transfer was studied using the B3LYP/6-31++G(d,p) level of theory, and the solvent effect (here DMF) on the PES was included using the conductor polarized continuum model (CPCM). For all cases, the energy profile for proton transfer represents a double well curve, if intermolecular O…Odistance for the hydrogen bond considered has a fixed length equal to 2.7 Å. The solvent effect favors a proton transfer in the molecular complexes, but no shift of the equilibrium towards ionic pairs is observed. As a result, the energy values associated with proton transfer are significantly reduced in comparison with those found for the gas phase. The proton transfer in the complexes of H3PO4 with DMF is more favored than this process for the cases with H3PO3 and СН3Н2РО3. The probability of proton transfer in the Н3РО4–DMF and (Н3РО4)2–DMF is nearly identical. On the contrary, the barrier height for transfer in Н3РО4–(DMF)n for n=1÷3 increases with increasing number of DMF molecules. The energy barrier for proton transfer in the DMFH+–DMF and H3PO4–H2PO4– is lower than the ones for the molecular complexes.

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