A possible role of chemical reduction in the memory switching process of bismuth oxide glasses

1984 ◽  
Vol 57 (3) ◽  
pp. 333-338 ◽  
Author(s):  
C. A. HOGARTH ◽  
A. B. GLOT ◽  
RAVISHANKAR HARANI
Keyword(s):  
Bismuth Oxide ◽  
Chemical Reduction ◽  
Switching Process ◽  
Oxide Glasses ◽  
Memory Switching

scholarly journals The Role of H2C2O4 and Na2CO3 as Precipitating Agents on The Physichochemical Properties and Photocatalytic Activity of Bismuth Oxide

2020 ◽  
Vol 18 (1) ◽  
pp. 129-137
Author(s):  
Yayuk Astuti ◽  
Rizka Andianingrum ◽  
Abdul Haris ◽  
Adi Darmawan ◽  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Physicochemical Properties ◽  
Bismuth Oxide ◽  
Rate Constants ◽  
Degradation Rate ◽  
Precipitation Method ◽  
Methyl Orange Degradation ◽  
Methyl Orange Dye

AbstractSynthesis of bismuth oxide synthesis through the precipitation method using H2C2O4 and Na2CO3 precipitating agents, identification of physicochemical properties and its photocatalysis activity for methyl orange degradation were conducted. The bismuth oxide synthesis was undertaken by dissolving Bi(NO3)3.5H2O in HNO3, then added precipitating agents to form precipitate. The results showed that bismuth oxide produced by H2C2O4 precipitating agent was a yellow powder containing a mixture of α-Bi2O3 (monoclinic) and β-Bi2O3 (tetragonal), porous with size of 28-85 μm. Meanwhile, the use of Na2CO3 as precipitating agent resulted in bismuth oxide consisting of α-Bi2O3 and β-Bi2O3 and Bi2O4, irregular shape without pore being 40-115 μm in size. Bismuth oxide synthesized with H2C2O4 precipitating agent showed higher photocatalytic activity compared to bismuth oxide synthesized using Na2CO3 on degrading methyl orange dye with degradation rate constants of 2.35x10-5 s-1 for H2C2O4 and 1.81x10-5 s-1 for Na2CO3.

Shielding behavior and structural role of bismuth oxide in ternary bismuth lead borate glass

2021 ◽  
Vol 0 (0) ◽  
pp. 0-0
Author(s):  
Noha Kattaya ◽  
Amr Abdelghany ◽  
Mahrous Meikhail ◽  
Osama Hemeda ◽  
Mohamed Ali
Keyword(s):  
Bismuth Oxide ◽  
Borate Glass ◽  
Lead Borate ◽  
Structural Role ◽  
Bismuth Lead

scholarly journals Role of Turmeric in Ultraviolet Induced Genotoxicity in a Bacterial System

2008 ◽  
Vol 3 (2) ◽  
pp. 1934578X0800300
Author(s):  
Arijit Pal ◽  
Mita Ghosh ◽  
Arun Kumar Pal
Keyword(s):  
Switching Process ◽  
Bacterial Dna ◽  
Bacterial System ◽  
Bioactive Component

Turmeric extracts contain more than one bioactive component, which have different properties when used to modulate ultraviolet induced genotoxicity. These differences were found depending on the nature and extent of the damage to the bacterial DNA, which indicates the existence of a natural switching process in sensing the damage.

Simulation of the structure of GeAs4Te7 chalcogenide materials during memory switching

2014 ◽  
Vol 92 (7/8) ◽  
pp. 675-680 ◽  
Author(s):  
M. Popescu ◽  
F. Sava ◽  
A. Velea ◽  
A. Lőrinczi ◽  
I.D. Simandan
Keyword(s):  
Amorphous Phase ◽  
Crystalline Phase ◽  
Glass Formation ◽  
Structural Changes ◽  
Amorphous Matrix ◽  
Switching Process ◽  
High Resistivity ◽  
Spatial Constraints ◽  
Memory Switching ◽  
Chalcogenide Materials

The complex chalcogenides with excellent memory switching properties are mainly situated close to the border of glass formation domain. The simulation of the structural changes occurring during the memory switching process of a ternary chalcogenide composition has been carried out. The transition of a high resistivity GeAs4Te7 amorphous cluster with 120 atoms to a low resistivity crystalline cluster was analyzed. The coordination of atoms changes from that corresponding to 8-N coordination rule (two for tellurium, three for arsenic, and four for germanium) in the amorphous phase to six (the same for all atoms) in metastable crystalline phase. Because of spatial constraints exercised by the amorphous matrix, the amorphous cluster cannot expand. In these circumstances Te atoms seem to be over-coordinated (up to sixfold-coordinated). During the switching process, the atoms are moving on distances up to 4.0 Å. The average displacement is of 2.36 Å.

scholarly journals Structural, Thermal and Optical Properties of Rare Earth Doped Lead-Tellurite Oxide Glasses

2021 ◽  
Vol 81 (2) ◽  
pp. 52-58
Author(s):  
Fong W. L. ◽  
Sharudin Omar Baki ◽  
N. M. Arifin ◽  
Yaakob Mansor ◽  
Ahmad Nazri ◽  
...  
Keyword(s):  
Optical Properties ◽  
Rare Earth ◽  
Energy Gap ◽  
Structural Deformation ◽  
Oxide Glasses ◽  
X Ray Diffraction ◽  
Optical Energy Gap ◽  
Erbium Ions ◽  
Glass Transformation

Structural, thermal and optical properties of lead-tellurite oxide glasses consisting TeO2 – PbO – Bi2O3 – Er2O3, synthesized by high temperature melt-quenching-thermal annealing method were investigated in this study. The role of rare-earth element, erbium ion as dopant into the host glass has affected physically, thermally and optically of the glasses. The amorphous nature of the glasses was confirmed by XRD (x-ray diffraction). Thermal exo-endothermic event profiles clarify its glass transformation temperature Tg, crystallization temperature Tx, and melting temperature Tm are exist. Both UV-Vis-NIR optical absorption and Raman spectroscopy have revealed optical energy gap changes due to the structural deformation by the erbium ions. Related obtained glass parameters such as polarizability, refractive indices and metallization criterion were also explained further in this study.

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