Ortho–para conversion of positronium in some rare-earth ion aqueous solutions

1989 ◽  
Vol 67 (1) ◽  
pp. 76-78 ◽  
Author(s):  
G. Consolati ◽  
F. Quasso
Keyword(s):  
Aqueous Solution ◽  
Rare Earth ◽  
Aqueous Solutions ◽  
Cross Sections ◽  
Previous Investigation ◽  
Lanthanide Ions ◽  
Rare Earth Ion ◽  
Contact Density ◽  
Electron Positron ◽  
Electron Positron Pair

We have extended a previous investigation by studying the ortho–para conversion of positronium in aqueous solutions of some lanthanide ions (Yb3+, Tm3+, Er3+, Dy3+, and Tb3+). The corresponding cross sections were found to be proportional to the number of unpaired electrons in the ion. Furthermore, the contact density of the electron–positron pair in the origin was obtained for a 1 M aqueous solution of ErCl3.

Rare Earth Ion from Aqueous Solution Removed by Polymer Enhanced Ultrafiltration Process

2011 ◽  
Vol 233-235 ◽  
pp. 959-964 ◽  
Author(s):  
Gui E Chen ◽  
De Sun ◽  
Zhen Liang Xu
Keyword(s):  
Aqueous Solution ◽  
Rare Earth ◽  
Low Ph ◽  
Water Soluble ◽  
Rare Earth Ion ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
Ion Rejection ◽  
Ultrafiltration Process ◽  
Added Salt

An efficiency of rare earth (europium, Eu) removal from aqueous solutions by polymer enhanced ultrafiltration (PEUF) process was investigated using two water-soluble polymers polyacrylic acid (PAA) and polyethylenimine (PEI). The effects of loading ratios of Eu to PAA or PEI, pH of solution and the added salt on Eu removal were evaluated. It was shown that the binding capacities for PAA and PEI to Eu ions were 0.8g Eu/g PAA and 0.5g Eu/g PEI, respectively. Eu ion rejection R decreased significantly at a low pH compared to the results at high pH, regardless of using PAA or PEI. Compared to the PAA case, PEI enhanced UF was more sensitive with changing pH. The effect of the added salt was slightly weak at pH 4-5.At the decomplexation stage, when permeate volume was equal to three times than that of the retentate, Eu removal efficiency (X) of Eu-PAA enhanced UF was 79.5% while that of Eu-PEI enhanced UF was 76.1%, and the polymer PAA and PEI could be recovered more than 97% and 93%, respectively. Eu in the retentate could be extracted effectively and the purified PAA and PEI solution were obtained. The recovered PAA and PEI solution was same as the fresh PAA and PEI solution in PEUF processes carried out by using the recovery recovered PAA and PEI as complex agents.

Dextran-rare earth ion interactions. I. Dynamics in aqueous solutions

2001 ◽  
Vol 82 (2) ◽  
pp. 323-329 ◽  
Author(s):  
H. Mazi ◽  
B. Zümreoğlu-Karan ◽  
A. Güner
Keyword(s):  
Rare Earth ◽  
Aqueous Solutions ◽  
Rare Earth Ion ◽  
Ion Interactions

scholarly journals Fabrication of sponge biomass adsorbent through UV-induced surface-initiated polymerization for the adsorption of Ce(III) from wastewater

2017 ◽  
Vol 75 (12) ◽  
pp. 2755-2764 ◽  
Author(s):  
Chen Liu ◽  
Chunjie Yan ◽  
Sen Zhou ◽  
Wen Ge
Keyword(s):  
Rare Earth ◽  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Adsorption Property ◽  
Three Dimensional ◽  
Soxhlet Extraction ◽  
Rare Earth Ions ◽  
Rare Earth Ion ◽  
Surface Initiated Polymerization ◽  
Insight Into

The recovery of rare earth ions from industrial wastewater has aroused wide concern in recent years. In present work, we synthesized a novel three-dimensional adsorbent (denoted as LF-AA) by grafting loofah fiber with acrylic acid via ultraviolet radiation. The LF-AA was washed by boiling water and subjected to soxhlet extraction with acetone and then fully characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). Rare earth ion (Ce(III)) was selected as a model to validate its adsorption property. The saturation adsorption capacity for Ce(III) reaches 527.5 mg/g. Not only was this material highly efficient at adsorbing Ce(III) from aqueous solutions, it also proved to have ideal performance in regeneration; the total adsorption capacity of LF-AA for Ce(III) after six successive cycles decreased only 6.40% compared with the initial capacity of LF-AA. More importantly, the LF-AA can be easily separated from aqueous solutions because of its three-dimensional sponge natural structure. This study provides a new insight into the fabrication of biomass adsorbent and demonstrated that the LF-AA can be used as excellent adsorbent for the recovery of rare earth ions from wastewater.

scholarly journals Compton Scattering, Pair Annihilation, and Pair Production in a Plasma

2000 ◽  
Vol 195 ◽  
pp. 359-366
Author(s):  
V. Krishan
Keyword(s):  
Compton Scattering ◽  
Cross Sections ◽  
High Plasma ◽  
Electron Positron ◽  
Pair Annihilation ◽  
The Cross ◽  
Unmagnetized Plasma ◽  
Electron Photon ◽  
Electron Positron Pair ◽  
Photon Coupling

The square of the four-momentum of a photon in vacuum is zero. However, in an unmagnetized plasma, it is equal to the square of the plasma frequency. Further, the electron-photon coupling vertex is modified in a plasma to include the effect of the plasma medium. I calculate the cross sections of three processes in a plasma—Compton scattering and electron-positron pair annihilation and production. At high plasma densities, the cross sections are found to change significantly. Such high plasma densities exist in several astrophysical sources.

π-Meson-Elektron-Streuung und Struktur des π-Mesons

1960 ◽  
Vol 15 (12) ◽  
pp. 1023-1030 ◽  
Author(s):  
H. Salecker
Keyword(s):  
Form Factor ◽  
Cross Sections ◽  
High Energy ◽  
Electromagnetic Structure ◽  
Electron Positron ◽  
Pair Annihilation ◽  
Very High Energy ◽  
Scattering Cross Sections ◽  
Electron Positron Pair ◽  
Very High

In this article we propose π-meson-electron scattering as a possibility for investigating the electromagnetic structure of the pion. This experiment requires very high energy, but not necessarily such a high accuracy as the extrapolation procedure of CHEW and Low. After a short discussion of the general properties of the electromagnetic formfactor of the π-meson, we calculate the π—e and the e—π scattering cross sections with form factor. With an energy of 25 GeV and a 10% experimental error we can probe the root mean square radius of the pion down to 0.8 10-13 cm, with 50 GeV down to 0.6·10-13 cm and with 100 GeV to 0.36·10-13 cm. The rms radius of the pion may be larger than previously assumed, because there exists the possibility of a fairly large π — π interaction. A complementary possibility for investigating the electromagnetic structure of the pion consists in electron-positron pair annihilation with the creation of a π± pair. This process will probe the form factor of the π-meson for timelike arguments.

Effect of thermal history of aqueous solutions of KCl on the metastable zone width

1984 ◽  
Vol 49 (3) ◽  
pp. 559-569 ◽  
Author(s):  
Jaroslav Nývlt
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Thermal History ◽  
Equilibrium Solubility ◽  
Metastable Zone Width ◽  
Zone Width ◽  
Preceding Experiment ◽  
History Of ◽  
Metastable Zone ◽  
The Given

The metastable zone width of an aqueous solution of KCI was measured as a function of the time and temperature of overheating above the equilibrium solubility temperature. It has been found that when the experiments follow close upon one another, the parameters of the preceding experiment affect the results of the experiment to follow.The results are interpreted in terms of hypotheses advanced in the literature to account for the effect of thermal history of solution. The plausibility and applicability of these hypotheses are assessed for the given cause of aqueous solution of a well soluble electrolyte.

scholarly journals I. Thermo-electric behaviour of aqueous solutions with mercurial electrodes

1879 ◽  
Vol 29 (196-199) ◽  
pp. 472-482 ◽  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Internal Diameter ◽  
Thermo Electric ◽  
Thin Glass ◽  
Mercury Surface

In order to investigate this subject, I devised and constructed the following apparatus :—A and B are two thin glass basins, 81 millims. internal diameter (= 5,153 sq. millims. of mercury surface), and 6·0 centims. deep; each containing a layer of mercury about 1·0 centim. deep, covered by a layer, about 3 centims. deep, of the aqueous solution to be examined.

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