scholarly journals Energy Transfer Between Yb3+- Mn2+ in Zn(Po3 ) 2 Glasses Giving Green, Red and Infrared Light

2020 ◽  
pp. 1-8
Author(s):  
C Flores J ◽  
◽  
J Hernández A ◽  
E Camarillo G ◽  
D Acosta N ◽  
...  
Keyword(s):  
Ion Pairs ◽  
Ion Concentration ◽  
Infrared Light ◽  
Electromagnetic Spectrum ◽  
Manganese Ion ◽  
Α Phase ◽  
Effective Option ◽  
Superexchange Coupling ◽  
Large Wavelength ◽  
Upconversion Process

The Yb3+-Mn2+codoped zinc metaphosphate glass gives rise to several processes such as upconversion, downshifting and double ion absorptions producing light from the visible to the IR wavelengths. These processes are possible since the Mn2+ and the Yb3+ ions replaces the Zn2+ ion in nanoparticles of the α phase of the compound Zn(PO3)2. An important result is that the α structure presence allows the formation of Yb3+-Mn2+ dimers, that gives rise to a superexchange coupling that allows an upconversion process from the IR to the red region of the electromagnetic spectrum. The experimental results also show that these dimers can couple to produce Yb3+ ion pairs that led to a cooperative emission in the green, around 500nm, coupling also the Mn2+ ions that in turn allows to produce a double absorption of this ions in the red region of the electromagnetic spectrum and as well a downshifting process conducting to the Yb3+ emission in the infrared. If the manganese ion concentration is higher than 10% most of these effects are masked. All these results make the material an effective option for different applications, due to the large wavelength variety that can be selected for excitation or emission

scholarly journals Energy Transfer Between Yb3+- Mn2+ in Zn(Po3 ) 2 Glasses Giving Green, Red and Infrared Light

2020 ◽  
pp. 1-8
Author(s):  
C Flores J J ◽  
◽  
J Hernández A ◽  
E Camarillo G ◽  
D Acosta N ◽  
...  
Keyword(s):  
Ion Pairs ◽  
Ion Concentration ◽  
Infrared Light ◽  
Electromagnetic Spectrum ◽  
Manganese Ion ◽  
Α Phase ◽  
Effective Option ◽  
Superexchange Coupling ◽  
Large Wavelength ◽  
Upconversion Process

The Yb3+-Mn2+codoped zinc metaphosphate glass gives rise to several processes such as upconversion, downshifting and double ion absorptions producing light from the visible to the IR wavelengths. These processes are possible since the Mn2+ and the Yb3+ ions replaces the Zn2+ ion in nanoparticles of the α phase of the compound Zn(PO3)2. An important result is that the α structure presence allows the formation of Yb3+-Mn2+ dimers, that gives rise to a superexchange coupling that allows an upconversion process from the IR to the red region of the electromagnetic spectrum. The experimental results also show that these dimers can couple to produce Yb3+ ion pairs that led to a cooperative emission in the green, around 500nm, coupling also the Mn2+ ions that in turn allows to produce a double absorption of this ions in the red region of the electromagnetic spectrum and as well a downshifting process conducting to the Yb3+ emission in the infrared. If the manganese ion concentration is higher than 10% most of these effects are masked. All these results make the material an effective option for different applications, due to the large wavelength variety that can be selected for excitation or emission.

scholarly journals Characterization of air ions in boreal forest air during BIOFOR III campaign

2005 ◽  
Vol 5 (3) ◽  
pp. 2749-2790 ◽  
Author(s):  
U. Hõrrak ◽  
P. P. Aalto ◽  
J. Salm ◽  
J. M. Mäkelä ◽  
L. Laakso ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Correlation Coefficient ◽  
Aerosol Particles ◽  
Ion Pairs ◽  
Ion Concentration ◽  
Cluster Ions ◽  
Statistical Characteristics ◽  
Nucleation Event ◽  
Air Ions ◽  
20 Nm

Abstract. The behavior of the concentration of positive small (or cluster) air ions and naturally charged nanometer aerosol particles (aerosol ions) has been studied on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. Statistical characteristics of the concentrations of cluster ions, two classes of aerosol ions of the sizes of 2.5–8 nm and 8–ca 20 nm and the quantities that determine the balance of small ions in the atmosphere have been given for the nucleation event days and non-event days. The dependence of small ion concentration on the ion loss (sink) due to aerosol particles was investigated applying a model of bipolar diffusion charging of particles by small ions. The small ion concentration and the ion sink were closely correlated (correlation coefficient 87%) when the fog events and the hours of high relative humidity (above 97%), as well as nocturnal calms and weak wind (wind speed<0.6 m s-1 had been excluded. In the case of nucleation burst events, variations in the concentration of small positive ions were in accordance with the changes caused by the ion sink due to aerosols; no clear indication of positive ion depletion by ion-induced nucleation was found. The estimated average ionization rate of air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 4.8 ion pairs cm-3 s-1. The study of the charging state of nanometer aerosol particles (2.5–8 nm) revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles and their charged fraction (positive air ions) during nucleation bursts. The estimated charged fraction of particles, which varied from 3% to 6% considering various nucleation event days, confirms that these particles are almost quasi-steady state charged. Also the particles and air ions in the size range of 8–ca 20 nm showed a good qualitative consistency; the correlation coefficient was 92%.

scholarly journals Characterization of positive air ions in boreal forest air at the Hyytiälä SMEAR station

2007 ◽  
Vol 7 (4) ◽  
pp. 9465-9517 ◽  
Author(s):  
U. Hõrrak ◽  
P. P. Aalto ◽  
J. Salm ◽  
K. Komsaare ◽  
H. Tammet ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Correlation Coefficient ◽  
Aerosol Particles ◽  
Ion Pairs ◽  
Coniferous Forest ◽  
Ion Concentration ◽  
Statistical Characteristics ◽  
Nucleation Event ◽  
Air Ions ◽  
20 Nm

Abstract. The behavior of the concentration of positive small (or cluster) air ions and naturally charged nanometer aerosol particles (aerosol ions) has been studied on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. Statistical characteristics of the concentrations of cluster ions, two classes of aerosol ions of the sizes of 2.5–8 nm and 8–ca. 20 nm and the quantities that determine the balance of small ions in the atmosphere have been given for the nucleation event days and non-event days. The dependence of small ion concentration on the ion loss (sink) due to aerosol particles was investigated applying a model of bipolar diffusion charging of particles by small ions. The small ion concentration and the ion sink were closely correlated (correlation coefficient –87%) when the fog events and the hours of high relative humidity (above 95%), as well as nocturnal calms and weak wind (wind speed <0.6 m s−1) had been excluded. However, an extra ion loss term presumably due to small ion deposition on coniferous forest with a magnitude equal to the average ion loss to pre-existing particles is needed to explain the observations. Also the hygroscopic growth correction of measured aerosol particle size distributions was found to be necessary for proper estimation of the ion sink. In the case of nucleation burst events, variations in the concentration of small positive ions were in accordance with the changes caused by the ion sink due to aerosols; no clear indication of positive ion depletion by ion-induced nucleation was found. The estimated average ionization rate of the air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 6 ion pairs cm−3 s−1. The study of the charging state of nanometer aerosol particles (2.5–8 nm) revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles and positively charged particles (positive air ions) during nucleation bursts. The estimated charged fraction of particles, which varied from 3% to 6% considering various nucleation event days, confirms that these particles are almost quasi-steady state charged. Also the particles and air ions in the size range of 8–ca. 20 nm showed a good qualitative consistency; the correlation coefficient was 92%.

scholarly journals Influence of zinc ion concentration on structure, morphology and optical properties of spray deposited ZnO thin films

2021 ◽  
Vol 10 (3) ◽  
pp. 198
Author(s):  
Sarika Vishvnbath Jadhav ◽  
Limbraj Sopan Ravangave
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Crystallite Size ◽  
Zinc Acetate ◽  
Zinc Ion ◽  
Ion Concentration ◽  
Zno Thin Films ◽  
Electromagnetic Spectrum ◽  
Structure Morphology ◽  
Wide Range

<p>Zinc Oxide (ZnO) thin films were deposited for five different molarity (M) of Zinc acetate hydrated (0.075, 0.1, 0.125, 0.15, 0.175 M) using simple spray technique to study the effect of zinc ion concentration on structure, morphology and optical properties. The XRD patterns of deposited ZnO thin films show hexagonal crystal structure with wurtzite symmetry. The effect of molarity on morphology was studied using scanning electron microscopy (SEM). The elemental analysis was studied by using energy dispersive X-ray analysis (EDX). The optical absorption was recorded by using systronics double beam spectrophotometer (2201). Crystallite size estimated from XRD data was in nanometre (nm) range; however, films deposited for 0.15 M zinc acetate show maximum crystallite size (66 nm) as compared to other samples. All the films show low absorption in wide range (340-999 nm) of electromagnetic spectrum. However, ZnO film deposited for 0.15 zinc acetate hydrated shows maximum blue shifting of absorption edge and higher band gap (3.8 eV) as compared to other samples.</p>

scholarly journals Improvement of near-infrared (NIR) reflectivity and black color tone by doping Zn2+ into the Ca2Mn0.85Ti0.15O4 structure

RSC Advances ◽  
2019 ◽  
Vol 9 (66) ◽  
pp. 38822-38827
Author(s):  
Ryohei Oka ◽  
Senri Iwasaki ◽  
Toshiyuki Masui
Keyword(s):  
Near Infrared ◽  
Ion Concentration ◽  
Color Tone ◽  
Infrared Reflectivity ◽  
Manganese Ion ◽  
Black Color

The near infrared reflectivity and black color tone of a Ca2Mn0.85Ti0.15O4 pigment were improved by the introduction of strain with Zn2+ doping into the [MnO6] octahedra and a decrease in the manganese ion concentration.

Bentonite-Biochar Combination for Manganese Ion Removal from Water

2021 ◽  
Vol 1162 ◽  
pp. 81-86
Author(s):  
Yasdi Yasdi ◽  
Rinaldi Rinaldi ◽  
Wahyu Fajar Winata ◽  
Febri Juita Anggraini ◽  
Ika Yanti ◽  
...  
Keyword(s):  
Contact Time ◽  
Metal Ion ◽  
Room Temperature ◽  
Adsorption Process ◽  
Quality Standard ◽  
Ion Concentration ◽  
Optimum Conditions ◽  
Manganese Ion ◽  
Ion Removal ◽  
Optimum Ph

Peat waters were abundant in the West Tanjung Jabung Regency of Jambi Province. Peat water contains manganese metal ion concentration that exceeds the clean water quality standard. Previous studies have been conducted to reduce levels of manganese in peat water, but the results have not been significant. This study aims to reduce levels of Manganese metal in peat water using the composition of Bentonite and Biochar. The adsorption process was carried out at room temperature (29 °C) with a stirring of 200 rpm. Some parameters measured were optimum pH of adsorption, optimum contact time and the best combination between Bentonite and Biochar. Manganese ion concentration in solution was measured using atomic absorption spectroscopy (AAS). The results of this study indicate that the optimum conditions for removing manganese ion at pH 5 and contact time 40 minutes. Tests on artificial solutions using 0.2 grams of biochar showed Mn ion removal of 42.91% (C0 = 100 mg/L, Ce = 57.09 mg/L, V = 100 mL). The best combination obtained in Bentonite: Biochar (1:2) with a mass of 0.080 gr and 0.170 gr, respectively, which able to remove 91.29% manganese ions in peat water.

ION PAIR EFFECTS IN THE REACTION BETWEEN POTASSIUM FERROCYANIDE AND POTASSIUM PERSULFATE

1966 ◽  
Vol 44 (4) ◽  
pp. 437-445 ◽  
Author(s):  
R. W. Chlebek ◽  
M. W. Lister
Keyword(s):  
Ionic Strength ◽  
Rate Constants ◽  
Equilibrium Constants ◽  
Ion Pairs ◽  
Ion Pair ◽  
Glass Electrode ◽  
Potassium Ferrocyanide ◽  
Potassium Persulfate ◽  
Ion Concentration ◽  
True Rate

The rate of the reaction between potassium ferrocyanide and potassium persulfate has been measured over a range of conditions. The rate is dependent on the potassium ion concentration, and it is shown that this is explained if it is assumed that KFe(CN)63− and KS2O8− are the reacting species. The equilibrium constants governing the formation of these ion pairs were measured with a cation-sensitive glass electrode. Similar constants for the products KFeCCN6)2− and KSO4−, and also for KNO3, were measured. From these equilibrium constants, the true rate constants of the reaction can be obtained, and it is shown that these vary with ionic strength in the manner predicted by Brönsted's equation.

scholarly journals Inhibition of Reverse Transcription In Vivo by Elevated Manganese Ion Concentration

2002 ◽  
Vol 9 (4) ◽  
pp. 879-889 ◽  
Author(s):  
Eric C Bolton ◽  
Albert S Mildvan ◽  
Jef D Boeke
Keyword(s):  
Reverse Transcription ◽  
Ion Concentration ◽  
Manganese Ion

scholarly journals Hybrid sol-gel materials for realization of radiation protective coatings—a review with emphasis on UV protective materials

2021 ◽  
Author(s):  
Boris Mahltig ◽  
Tilmann Leisegang ◽  
Melanie Jakubik ◽  
Helfried Haufe
Keyword(s):  
Radiation Protection ◽  
Gamma Ray ◽  
Uv Light ◽  
Protective Coatings ◽  
Sol Gel ◽  
Infrared Light ◽  
Electromagnetic Spectrum ◽  
Radio Waves ◽  
Protective Properties ◽  
Different Types

AbstractThis review reports on hybrid sol-gel coatings used for radiation protective purposes. The different types of electromagnetic radiation are usually distinguished by their wavelength, frequency or photon energy. There is a broad range of types of radiation that humans, materials or electric devices are exposed to, starting from radio waves, microwaves, infrared radiation, visible light, UV light, X-ray and gamma-ray radiation. Gamma-ray radiation is thus at the end of the electromagnetic spectrum with smallest wavelengths, highest frequencies and highest photon energies. Protection against radiation make sense, as it can pose health risks or interfere with technical and electronic equipment for example. Radiation protection can be realized by materials that are able to absorb or reflect the radiation, which leads to a considerable reduction in radiation transmission. These radiation protection materials are specific to different types of radiation or spectral widths, e.g., a material with excellent protective properties against UV light is not automatically suitable for protection against infrared light. The main aim of this review article is to report, what types of hybrid sol-gel materials can be used to provide ideal protection against a specific category of radiation. Additional to the broad view on all types of radiations, focusing in particular on materials exhibiting UV protective properties.

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