scholarly journals The Relationship between the Structure and Thermal Properties of Bi2O3-ZnO-B2O3 Glass System

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Sung-Hung Lan ◽  
Chin-Tung Lee ◽  
Yi-Sheng Lai ◽  
Chien-Chon Chen ◽  
Hsi-Wen Yang
Keyword(s):  
Thermal Properties ◽  
Melting Temperature ◽  
Color Change ◽  
Glass Structure ◽  
Glass System ◽  
Light Transmittance ◽  
Optical Applications ◽  
The Relationship ◽  
B2o3 Glass ◽  
Temperature Melting

The influence of Bi2O3 and melting temperature on the thermal and structural properties of xBi2O3-(60-x) ZnO-40B2O3 glasses has been investigated in this study. It is expected that these factors can be used to control the degree of reduction of Bi2O3, and the relationship between these factors and the color change of the process for bismuth glass is discussed. Due to high-temperature melting, the bismuth-doped borate glasses have changed into dark/black from original transparent yellow and the light transmittance will decrease, so it is not used in optical applications. The thermal properties of glass are measured by a thermomechanical analyzer (TMA), and the glass structure is analyzed by FTIR and XPS. The results show that the glass is mainly composed of [BiO6] octahedron, [BiO3] triangle, [BO4] tetrahedron, and triangle [BO3] units, and the network of the glass system is mainly bonded by B-O-B, B-O-Zn, B-O-Bi, and Bi-O-Bi. The glass thermal expansion coefficient (CTE) of this glass system increases with the increase of Bi2O3 content, and the O1s nuclear electron binding energy shifts to the lower energy direction with the increase of Bi2O3 addition. In terms of FTIR, as the melting temperature rises, the B-O-B bonding vibration concentration of [BO4] inside the borate glass decreases, and the density of B-O-B bonding vibration of [BO3] increases, Moreover, the increase in melting temperature increases the probability of reducing Bi ions to Bi0, reduces the bonding of Bi-O-B, and increases the bonding of B-O-B, and the CTE also slightly decreases.

scholarly journals OPTICAL PROPERTIES ON Li2O-K2O-WO3-B2O3 GLASS SYSTEM

2013 ◽  
Vol 22 ◽  
pp. 278-283
Author(s):  
A. EDUKONDALU ◽  
M. A. SAMEE ◽  
SHAIKH KAREEM AHMMAD ◽  
SAIR MD. TAQIULLAH ◽  
SYED RAHMAN ◽  
...  
Keyword(s):  
Glass Structure ◽  
Glass System ◽  
Alkali Concentration ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Mixed Alkali ◽  
Absorption Studies ◽  
Mixed Alkali Effect ◽  
Oxide Ion ◽  
B2o3 Glass

Mixed alkali tungsten borate glasses xLi2O–(30–x) K2O–10WO3–60B2O3 (0 < x < 30) were prepared from the melts. These glasses were characterized using X-ray diffraction, differential scanning calorimetry and density measurements. Optical absorption studies were carried out as a function of alkali content to look for mixed alkali effect (MAE) on the spectral properties of these glasses. From the study of ultraviolet absorption edge, the optical band gap energies and Urbach energies were evaluated. The average electronic polarizability of the oxide ion, optical basicity and the interaction parameters were also evaluated for all the glasses. Many of these parameters vary non-linearly exhibiting a minima or maxima with increasing alkali concentration, indicating the mixed alkali effect. An attempt is made to interpret MAE in this glass system in terms of its glass structure.

Effect of K2O Contents on the Releasing of Nutrient Ions from Phosphate Glass System

2016 ◽  
Vol 723 ◽  
pp. 545-550
Author(s):  
Siti Hafizah Mohamad ◽  
Mohd Al Amin Muhamad Nor
Keyword(s):  
Melting Temperature ◽  
Phosphate Glass ◽  
Glass Surface ◽  
Ph Value ◽  
Glass Structure ◽  
Phosphate Glasses ◽  
Glass System ◽  
Spectroscopy Analysis ◽  
O 29 ◽  
Solubility Study

Currently, the solubility of phosphate glasses has been extensively studied for potential glass fertilizer. This work presents the study of 45P2O5-20CaO-xK2O-(29-x)Na2O-6Al2O3 glass, where x equals to 5, 10, 15 and 20 wt. % of K2O. Free bubble glasses were obtained at melting temperature of 1300 °C. Solubility study of phosphate glass indicates that the glass containing 15 wt. % of K2O released the highest amounts of PO43- ion and K+ ion and it exhibits the lowest pH value compare to other glasses. Spectroscopy analysis revealed the addition of K2O to the glass system contributed to the formation of metaphosphate and phyrophosphate units around 919 cm-1 and 1119 cm-1. The morphology analysis indicates the formation of pores on the glass surface was associated with the corrosion of the glass samples due to the immersion. The addition of K2O to the glass system has increased the glass solubility due to the breakup of the glass structure.

Thermal Properties and Transition Temperatures of AlB2-Type Diborides

2015 ◽  
Vol 817 ◽  
pp. 740-747
Author(s):  
Ming Jun Peng ◽  
Yong Hua Duan ◽  
Yong Sun
Keyword(s):  
Thermal Properties ◽  
Bulk Modulus ◽  
Melting Temperature ◽  
First Principles ◽  
Transition Temperatures ◽  
Coupling Constant ◽  
Phonon Coupling ◽  
Electron Phonon Coupling ◽  
The Relationship ◽  
Theoretical Results

The thermal properties, cohesion and transition temperatures of 14 compounds in the AlB2-type diborides have been calculated by first-principles. The obtained thermal properties, cohesion and transition temperatures Tc were compared with both available experimental data and other theoretical results. The relationship among enthalpy formation, bulk modulus and melting temperature in these diborides were further analyzed. The results illustrate that ZrB2 is the most stable, and AuB2 has the largest c/a ratio and it is also most unstable to a phase separation. It is observed that the diborides including Mg, Sc, and Hf series with a more negative enthalpy of formation have a larger bulk modulus and higher melting temperature. AuB2 has higher electron-phonon coupling constant and hence possesses a higher Tc.

Refractive Index of SiO2-B2O3-Al2O3 Glasses

2008 ◽  
Vol 569 ◽  
pp. 349-352 ◽  
Author(s):  
Ju Yeon Won ◽  
Sang Wook Lee ◽  
Dong Sun Kim ◽  
Jung Ki Lee ◽  
Seong Jin Hwang ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Structural Transition ◽  
Glass Structure ◽  
Glass System ◽  
Borosilicate Glasses ◽  
The Relationship

Photolithographic process is one of the eco-friendly processes for forming the pattern of the barrier ribs in PDP. Controlling the refractive index of glass is important to develop a photosensitive paste for photolithographic process. We studied the refractive index and the structural transition of these glasses by measuring the refractive index, reflectance, density and dielectric constant with changing the SiO2/B2O3 ratio in the SiO2-B2O3-Al2O3 glass system. The refractive index was investigated to the relationship between the thermal and optical properties depending on the composition. It suggests that the thermal and optical properties in borosilicate glasses should be correlated to the glass structure with the SiO2/B2O3 ratio.

scholarly journals DC and AC Conductivity, Biosolubility and Thermal Properties of Mg-Doped Na2O–CaO–P2O5 Glasses

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2626
Author(s):  
Natalia Anna Wójcik ◽  
Sharafat Ali ◽  
Jakub Lech Karczewski ◽  
Bo Jonson ◽  
Michał Bartmański ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Saline Solution ◽  
Glass Structure ◽  
Glass Network ◽  
Bioactive Glasses ◽  
Dc And Ac Conductivity ◽  
Impedance Spectroscopy Technique ◽  
Mg Content ◽  
Phosphate Buffered Saline ◽  
Mg Doped

Bioactive glasses have recently been extensively used to replace, regenerate, and repair hard tissues in the human body because of their ability to bond with living tissue. In this work, the effects of replacing Na2O with MgO on the electrical, biosolubility, and thermal properties of the target glass 10Na2O–60P2O5–30CaO (in mol%) were investigated. The electrical properties of the glasses were studied with the impedance spectroscopy technique. At 473 K, DC conductivity values decreased from 4.21 × 10−11 to 4.21 × 10−12 S cm−1 after complete substitution of MgO for Na2O. All samples had a similar activation energy of the DC conduction process ~1.27 eV. Conduction mechanisms were found to be due to hop of ions: Na+, Mg2+, and probable H+. FTIR analysis showed that, as the Mg content increased, the Q2 unit (PO2−) shifted towards higher wavenumbers. The proportion of Q3 unit (P2O5) decreased in the glass structure. This confirmed that the replacement of Na+ by Mg2+ was accompanied by concurrent polymerization of the calcium–phosphate glass network. The biosolubility test in the phosphate-buffered saline solution showed that the magnesium addition enhanced the biosolubility properties of Na2O–CaO–P2O5 glasses by increasing their dissolution rate and supporting forming CaP-rich layers on the surface. The glass transition temperature increased, and thermal stability decreased substantially upon substitution of Na2O by MgO.

Effects of Molecular Weight of Chitosan on the Biodegradability and Thermal Properties of Polybutylene Succinate/Chitosan Composites

2018 ◽  
Vol 775 ◽  
pp. 26-31
Author(s):  
Sukantika Manatsittipan ◽  
Kamonthip Kuttiyawong ◽  
Kazuo Ito ◽  
Sunan Tiptipakorn
Keyword(s):  
Molecular Weight ◽  
Weight Loss ◽  
Thermal Properties ◽  
Water Absorption ◽  
Melting Temperature ◽  
Microbial Degradation ◽  
Decomposition Temperature ◽  
Molecular Weights ◽  
Significant Difference ◽  
Polybutylene Succinate

In this study, the biodegradability and thermal properties the composites of polybutylene succinate (PBS) and chitosan of different molecular weights (Mn = 104,105, and 106 Da) were prepared at chitosan contents of 0-10 wt%. After 10 days of microbial degradation, the results show that the amount of holes from degradation was increased with either decreasing Mn or increasing chitosan contents. However, the size of holes was increased with increasing Mn and chitosan contents. The results from Differential Scanning Calorimeter (DSC) present that the melting temperature (Tm) of PBS was decreased with increasing chitosan contents. Moreover, there was no significant difference between Tm of the composites with different Mn of chitosan. From the TGA thermograms, the decomposition temperature at 10% weight loss (Td10) was decreased with increasing chitosan contents. Moreover, the water absorption of PBS/chitosan composites was increased with increasing Mn and content of chitosan.

Anomalous elastic behaviour of xSrO-10PbO-(90-x)B2O3 glass system

2016 ◽  
Vol 444 ◽  
pp. 55-63 ◽  
Author(s):  
Nurul Syahidah Sabri ◽  
A.K. Yahya ◽  
R. Abd-Shukor ◽  
Mahesh Kumar Talari
Keyword(s):  
Glass System ◽  
Elastic Behaviour ◽  
B2o3 Glass

scholarly journals Effect of Pb2+ Ions on the Mechanical, Structural and Thermal Behaviour of B2O3-CaO Glasses

2019 ◽  
Vol 32 (1) ◽  
pp. 101-105
Author(s):  
C. Subashini ◽  
R. Ezhil Pavai ◽  
L. Balu
Keyword(s):  
Glass Structure ◽  
Measured Data ◽  
Micro Hardness ◽  
Ultrasonic Velocities ◽  
Structural Units ◽  
Amorphous Nature ◽  
Longitudinal Modulus ◽  
Pulse Echo ◽  
Temperature Melting ◽  
Sem Analyses

B2O3-CaO-PbO glasses with different concentrations of PbO (5-20 mol % in four steps) were prepared by melt quench technique. The amorphous nature and homogeneities of the prepared glasses were confirmed by XRD and SEM analyses. Ultrasonic velocities and density were measured at 303 K using pulse-echo technique and Archimedes’ principle respectively. Various parameters, viz., molar volume, longitudinal modulus, shear modulus, bulk modulus, Young’s modulus, Poisson’s ratio, micro-hardness and Debye temperature have been evaluated from the measured data. The results of ultrasonic properties indicate that the incorporation of lead ions expand the calcium borate network structure. FTIR spectra revealed that boron exists in both trigonal and tetrahedral structural units and no boroxial ring formation takes place in the glass structure. The transition temperature, melting temperature and crystallization temperature have been identified using DTA measurements.

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