scholarly journals Strong Binding of Noble Gases to [B12X11]˗: A Theoretical Study

2021 ◽  
Author(s):  
Kevin Wöhner ◽  
Toshiki Wulf ◽  
Nina Vankova ◽  
Thomas Heine
Keyword(s):  
Charge Transfer ◽  
Low Temperatures ◽  
Room Temperature ◽  
Noble Gases ◽  
Theoretical Study ◽  
Ion Trap ◽  
Noble Gas ◽  
Capture Reaction ◽  
Strong Binding ◽  
The Stability

We systematically explore the stability and properties of [B<sub>12</sub>X<sub>11</sub>Ng]<sup>−</sup> adducts resulting from the capture reaction of noble gas atoms (Ng) by anionic [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> clusters in the ion trap. [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> can be obtained by stripping one X<sup>−</sup> ligand off the icosahedral <i>closo</i>-dodecaborate dianion [B<sub>12</sub>X<sub>12</sub>]<sup>2</sup><sup>−</sup>. We study the binding of the noble gas atoms He, Ne, Kr, Ar and Xe to [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> with ligands X = F, Cl, Br, I, CN. While He cannot be captured by these clusters and Ne only binds at low temperatures, the complexes with the heavier Kr, Ar and Xe show appreciable complexation energies and exceed 1 eV at room temperature in the case of [B<sub>12</sub>(CN)<sub>11</sub>Xe]<sup>−</sup>. For the latter three noble gases, we observe a significant charge transfer from the Ng to the icosahedral B<sub>12</sub> cage.

scholarly journals Strong Binding of Noble Gases to [B12X11]˗: A Theoretical Study

2021 ◽  
Author(s):  
Kevin Wöhner ◽  
Toshiki Wulf ◽  
Nina Vankova ◽  
Thomas Heine
Keyword(s):  
Charge Transfer ◽  
Low Temperatures ◽  
Room Temperature ◽  
Noble Gases ◽  
Theoretical Study ◽  
Ion Trap ◽  
Noble Gas ◽  
Capture Reaction ◽  
Strong Binding ◽  
The Stability

We systematically explore the stability and properties of [B<sub>12</sub>X<sub>11</sub>Ng]<sup>−</sup> adducts resulting from the capture reaction of noble gas atoms (Ng) by anionic [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> clusters in the ion trap. [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> can be obtained by stripping one X<sup>−</sup> ligand off the icosahedral <i>closo</i>-dodecaborate dianion [B<sub>12</sub>X<sub>12</sub>]<sup>2</sup><sup>−</sup>. We study the binding of the noble gas atoms He, Ne, Kr, Ar and Xe to [B<sub>12</sub>X<sub>11</sub>]<sup>−</sup> with ligands X = F, Cl, Br, I, CN. While He cannot be captured by these clusters and Ne only binds at low temperatures, the complexes with the heavier Kr, Ar and Xe show appreciable complexation energies and exceed 1 eV at room temperature in the case of [B<sub>12</sub>(CN)<sub>11</sub>Xe]<sup>−</sup>. For the latter three noble gases, we observe a significant charge transfer from the Ng to the icosahedral B<sub>12</sub> cage.

scholarly journals Noble Gases in Terrestrial Planets: Evidence for Cometary Impacts?

1989 ◽  
Vol 116 (1) ◽  
pp. 429-437
Author(s):  
Tobias Owen ◽  
Akiva Bar-Nun ◽  
Idit Kleinfeld
Keyword(s):  
Low Temperatures ◽  
Noble Gases ◽  
Noble Gas ◽  
Terrestrial Planets ◽  
Laboratory Studies ◽  
The Impact ◽  
Gas Patterns ◽  
Atmosphere Of Venus

AbstractThe possible role of comets in bringing volatiles to the inner planets is investigated by means of laboratory studies of the ability of ice to trap gases at low temperatures. The pattern of the heavy noble gases formed in the atmosphere of Venus can be explained by the impact of a planetesimal composed of ices formed in the range of 20 to 30 K. The noble gas patterns on Mars and Earth are less explicable by cometary bombardment alone.

A theoretical study of complexes between fullerenes and concave receptors with interest in photovoltaics

2017 ◽  
Vol 19 (39) ◽  
pp. 26787-26798 ◽  
Author(s):  
E. M. Cabaleiro-Lago ◽  
J. Rodríguez-Otero ◽  
J. A. Carrazana-García
Keyword(s):  
Charge Transfer ◽  
Theoretical Study ◽  
Receptor Complexes ◽  
Transfer Capability ◽  
The Stability

The proper combination of host and guest allows controlling the stability and charge transfer capability of fullerene–concave receptor complexes.

scholarly journals Mesophase behaviour of a cyanobiphenyl molecule in polar aprotic solvent: Rigidity effect

2020 ◽  
Vol 31 (3) ◽  
pp. 33-45
Author(s):  
Suraj Kumar Nayak ◽  
◽  
P. Lakshmi Praveen ◽  
Keyword(s):  
Transition Temperature ◽  
Room Temperature ◽  
Theoretical Study ◽  
Aprotic Solvent ◽  
Molecular Models ◽  
Polar Aprotic Solvent ◽  
Rigidity Parameter ◽  
The Stability ◽  
Modes Of Interaction ◽  
Crystal Compound

In this paper, a theoretical study has been carried out on a liquid crystal compound named p-n-propyl cyanobiphenyl (3CB). The different modes of interaction energy values in a polar aprotic solvent (ethyl acetate) for small amount of translation and rotation are calculated. The corresponding probabilities have been calculated at both room temperature (300 K) and transition temperature (303.3 K). The rigidity parameter for stacking and in-plane interactions has been estimated and then the stability of molecule according to probability and rigidity at definite translation and rotation has been concluded. The change in the characteristics and stability of the compound at transition temperature has been observed. The dependence of mesophase behaviour with change in the certain configurations and orientation of the molecules have been discussed. These observed results provide an insight about the process of mesophase structure and its formation. The present compound may guide in establishing the other molecular models with transition temperature nearer to room temperature.

Strong Binding of Noble Gases to [B12X11]−: A Theoretical Study

2021 ◽  
Author(s):  
Kevin Wöhner ◽  
Toshiki Wulf ◽  
Nina Vankova ◽  
Thomas Heine
Keyword(s):  
Noble Gases ◽  
Theoretical Study ◽  
Strong Binding

scholarly journals Response of QIT-MS to Noble Gas Isotopic Ratios in a Simulated Venus Flyby

Atmosphere ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 232 ◽  
Author(s):  
Nikolić ◽  
Madzunkov ◽  
Darrach
Keyword(s):  
Noble Gases ◽  
Ion Trap ◽  
Noble Gas ◽  
A Priori ◽  
Quadrupole Ion Trap ◽  
Active Species ◽  
Primary Objective ◽  
Ion Trapping ◽  
Qit Ms ◽  
Venus Atmosphere

The primary objective of the present study is to investigate the science return of future Venus atmosphere probe mission concepts using the Quadrupole Ion Trap (QIT) Mass Spectrometer (MS) Instrument (QIT-MS-I). We demonstrate the use of Monte-Carlo simulations in determining the optimal ion trapping conditions and focus the analysis on retrieving isotope ratios of noble gases in the model sample of the Venus atmosphere. Sampling takes place at a constant velocity of ~10 km/s between 112–110 km altitude and involves the use of getter pumps to remove all chemically-active species, retaining inert noble gases. The enriched sample is leaked into passively pumped vacuum chamber where it is analyzed by the QIT-MS sensor (QIT-MS-S) for 40 minutes. The simulated mass spectrum, as recorded by the QIT-MS-S, is deconvoluted using random walk algorithm to reveal relative abundances of noble gas isotopes. The required precision and accuracy of the deconvolution method is benchmarked against the a priori known model composition of the atmospheric sample.

scholarly journals Dissolution of Ordered Precipitates under ion Irradiation

1994 ◽  
Vol 373 ◽  
Author(s):  
Eric Camus ◽  
Françise Bourdeau ◽  
Christian Abromeit ◽  
Nelja Wanderka ◽  
Heinrich Wollenberger
Keyword(s):  
Electron Microscopy ◽  
Low Temperatures ◽  
Room Temperature ◽  
Ion Irradiation ◽  
Atom Probe ◽  
Precipitate Dissolution ◽  
The Matrix ◽  
Ion Microscopy ◽  
The Stability ◽  
Atomic Mixing

AbstractThe stability of the ordered γʹ precipitates under 300-keV Ni+ irradiation was investigated between room temperature and 623 K. The two competing mechanisms of destabilization by cascade producing irradiation, i. e. disordering and dissolution of the γʹ precipitates in Nimonic PE16 alloy, has been studied separately by electron microscopy and field-ion microscopy with atom probe. At high temperatures, the precipitates are stable. At intermediate temperatures, the precipitates dissolve by ballistic mixing into the matrix, but the interface is restored by the radiation-enhanced atomic jumps. The order in the precipitates remains stable. At low temperatures, the precipitates are dissolved by atomic mixing. The dissolution proceeds in a diffusional manner with a diffusion coefficient normalized by the displacement rate D/K = 0.75 nm2dpa−1. The precipitates become disordered by a fluence of 0.1 dpa, whereas precipitate dissolution needs much higher fluences.

The Stability of CeNi3-Based Intermetallic Hydrides

2015 ◽  
Vol 365 ◽  
pp. 24-29
Author(s):  
Stepan Alexandrovich Lushnikov ◽  
Tatyana Victorovna Filippova
Keyword(s):  
Phase Composition ◽  
Low Temperatures ◽  
Room Temperature ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
X Ray ◽  
The Stability ◽  
Diffusion Of Hydrogen ◽  
Hydride Phases

Hydrides of CeNi3 intermetallic compounds were synthesized with hydrogen at a pressure of up to 50 bars at room and low temperatures. Using the X-ray diffraction method gives phase composition and lattice parameters of the hydride samples. It was revealed that one set of the hydride samples was stable in air and at room temperature, while another set was very unstable at the same conditions and rapidly desorbed hydrogen. This diverse behaviour depends on the proportion of obtained hydride phases at low and room temperatures, coexisting in the samples. A possible explanation has been proposed based on the different diffusion of hydrogen atoms in ordered and disordered hydride phases, incorporated in the samples.

Methods for the Concentration of Bovine Ac-Globulin (Factor V)

1961 ◽  
Vol 06 (03) ◽  
pp. 435-444 ◽  
Author(s):  
Ricardo H. Landaburu ◽  
Walter H. Seegers
Keyword(s):  
Room Temperature ◽  
Barium Carbonate ◽  
Deae Cellulose ◽  
Reducing Agents ◽  
Factor V ◽  
Isoelectric Precipitation ◽  
Stabilizing Agent ◽  
Bovine Plasma ◽  
The Stability

SummaryAn attempt was made to obtain Ac-globulin from bovine plasma. The concentrates contain mostly protein, and phosphorus is also present. The stability characteristics vary from one preparation to another, but in general there was no loss before 1 month in a deep freeze or before 1 week in an icebox, or before 5 hours at room temperature. Reducing agents destroy the activity rapidly. S-acetylmercaptosuccinic anhydride is an effective stabilizing agent. Greatest stability was at pH 6.0.In the purification bovine plasma is adsorbed with barium carbonate and diluted 6-fold with water. Protein is removed at pH 6.0 and the Ac-globulin is precipitated at pH 5.0. Rivanol and alcohol fractionation is followed by chromatography on Amberlite IRC-50 or DEAE-cellulose. The final product is obtained by isoelectric precipitation.

Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

2020 ◽  
Author(s):  
Katsuya Maruyama ◽  
Takashi Ishiyama ◽  
Yohei Seki ◽  
Kounosuke Oisaki ◽  
Motomu Kanai
Keyword(s):  
Reaction Time ◽  
Steric Hindrance ◽  
Room Temperature ◽  
Water Soluble ◽  
Light Irradiation ◽  
Sodium Ascorbate ◽  
Iminoxyl Radical ◽  
Short Reaction Time ◽  
Modified Peptides ◽  
The Stability

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

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