Read by QxMD icon Read

Bismuth silicate

Daniel T Bowron, Jonathan Booth, Nathan S Barrow, Patricia Sutton, Simon R Johnson
Low levels of transition metal oxides in alkali borosilicate glass systems can drastically influence crystallisation and phase separation properties. We investigated the non-monotonic effect of manganese doping on suppressing crystallisation, and the influence on optical properties by iron oxide doping, in terms of local atomic structure. Structural models based on empirical potential structure refinement were generated from neutron and X-ray scattering data, and compared against multinuclear solid-state NMR...
May 9, 2018: Physical Chemistry Chemical Physics: PCCP
T Zarra, T Lambrianidis, L Vasiliadis, C Gogos
AIM: To evaluate setting time, pH, solubility and surface roughness of MTA+ and ProRoot MTA and characterize their hydration under several curing conditions. METHODOLOGY: Specimens were prepared to evaluate setting time (n=6 for each group, specimen dimensions 10x8x5mm), solubility (n=6 for each group, specimen dimension 20 mm in diameter and 1.5 mm thick) after 1 and 28 days, pH (n=10 for each group, specimen dimensions 10 mm in diameter and 1 mm thick) after 1, 7, 14, 21 and 28 days and surface roughness (n=10 for each group, specimen dimensions 4 mm in diameter and 3 mm high) after 28 days when cements were cured at 95% humidity or immersed in saline or HBSS at 37°C...
April 12, 2018: International Endodontic Journal
Feiyang Chen, Meng Ju, Xiaoyu Kuang, Yauyuen Yeung
Due to its unusual optical properties, neodymium ion (Nd3+ )-doped bismuth silicate (Bi4 Si3 O12 , BSO) is widely used for its excellent medium laser amplification in physics, chemistry, biomedicine, and other research fields. Although the spectral transitions and luminescent mechanisms of Nd3+ -doped BSO have been investigated experimentally, theoretical research is severely limited due to the lack of detailed information about the microstructure and the doping site of Nd3+ -doped BSO, as well as the electric and magnetic dipole transition mechanisms...
March 27, 2018: Inorganic Chemistry
Seok Woo Chang
Chemical composition and porosity characteristics of calcium silicate-based endodontic cements are important determinants of their clinical performance. Therefore, the aim of this study was to investigate the chemical composition and porosity characteristics of various calcium silicate-based endodontic cements: MTA-angelus, Bioaggregate, Biodentine, Micromega MTA, Ortho MTA, and ProRoot MTA. The specific surface area, pore volume, and pore diameter were measured by the porosimetry analysis of N2 adsorption/desorption isotherms...
2018: Bioinorganic Chemistry and Applications
F B Basturk, Mohammad Hossein Nekoofar, M Gunday, P M H Dummer
OBJECTIVES: The aim of this study was to evaluate the effect of various mixing techniques as well as the effect of ultrasonic placement on hydration of mineral trioxide aggregate (MTA) using X-ray diffraction (XRD) analysis. MATERIALS AND METHODS: One gram of ProRoot MTA and MTA Angelus powder was mixed with a 0.34-g of distilled water. Specimens were mixed either by mechanical mixing of capsules for 30 s at 4500 rpm or by manual mixing followed by application of a compaction pressure of 3...
December 29, 2017: Clinical Oral Investigations
Amar Al-Keisy, Long Ren, Tian Zheng, Xun Xu, Michael Higgins, Weichang Hao, Yi Du
The photocatalytic activity of ferroelectric materials is highly influenced by the main direction of charge separation, originating from spontaneous polarization. In this work, unique bismuth silicate based zero-dimensional (0D)/two-dimensional (2D) heterogeneous nanostructures were successfully constructed. In contrast to either individual pristine phase, this heterogeneous structure exhibited much enhanced photocatalytic activity towards the degradation of Rhodamine B and phenol. The synergistic effects of high polarization in 2D ferroelectric Bi2 SiO5 nanosheets and the band bending at the 0D-2D interface of the heterostructures have been proved to accelerate the photoinduced charge separation and the movement of separated carriers to the interface, which further improves the photodegradation performance...
November 14, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Fatemeh Panahi, Sayed Mahmood Rabiee, Reza Shidpour
In recent years, cement composites based on calcium silicate have been more generally considered for medical applications. Calcium silicate Cement are among the categories that are used in dental root canal treatment. The aim of this study is to make new calcium silicate cement with dicalcium phosphate and chitosan additives to preserve and strengthen desirable properties of this type of cements. In this study, composite dental cement based on calcium silicate was prepared. Then effect of adding biodegradable and biocompatible polymer such as chitosan on setting properties and its structure were studied...
November 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Kun-Le Jia, Jin Qu, Shu-Meng Hao, Fei An, Ya-Qiong Jing, Zhong-Zhen Yu
Construction of a heterostructure to prolong the life of electron-hole pairs is a very important approach to endow it with excellent photodegradation performances. Particularly, one-pot synthesis of heterostructures with the same component but different crystal structures to form a proper band gap is still challenging. Herein, bismuth silicate (BSO) heterostructures are synthesized using a one-pot hydrothermal approach without adding any other inorganic components. The crystal phase, morphology, surface state, and photochemical properties of the BSO materials are precisely tuned to fabricate two kinds of bismuth silicate heterostructures: rod-like Bi2SiO5/Bi12SiO20 and flower-like Bi2SiO5/Bi4Si3O12 heterostructures...
November 15, 2017: Journal of Colloid and Interface Science
Yiyan Song, Zhihui Xu, Xinyu Yu, Xueyan Shi, Huijun Jiang, Xiaoming Li, Yan Kong, Qin Xu, Jin Chen
BiOCl-SiO₂ KIT-6 composite materials with raspberry-like structures are facilely prepared under hydrothermal conditions. The mesoporous siliceous support of SiO₂ KIT-6-incorporated BiOCl with enlarged yet refined surface morphology characterized by physiochemical methods exhibits an improved electrochemical performance. A sensitive electrochemical detection method of cadmium concentration using square wave anodic stripping voltammetry was developed based on BiOCl-SiO₂ KIT-6 composite-modified glassy carbon electrodes, which displayed wide linear ranges of 0...
May 13, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Yan Zhang, Jiayue Xu, Qingzhi Cui, Bobo Yang
Europium-doped bismuth silicate (Bi4Si3O12) phosphor has been prepared by microwave irradiation method and its crystal structure is determined using Rietveld method. As-prepared phosphor consists of spherical, monodispersed particles with few agglomeration, high crystallinity, and narrow grain size distribution. The phosphor can be efficiently excited in the wavelength range of 260-400 nm, which matched well with the emission wavelengths of NUV LED chips. The photoluminescence spectra exhibit the highest emission peak at 703 nm originating from (5)D0 → (7)F4 transition of Eu(3+) under NUV excitation...
February 15, 2017: Scientific Reports
L Cianconi, P Palopoli, V Campanella, M Mancini
AIM: The aim of this study was to determine the chemical composition and the phases' microstructure of Aureoseal Plus (OGNA, Italy) and ProRoot MTA (Dentsply Tulsa Dental, USA) and to compare their characteristics. MATERIALS AND METHODS: Study Design: Comparing Aureoseal Plus and ProRoot MTA microstructure by means of several analyses type. The chemical analysis of the two cements was assessed following the UNI EN ISO 196-2 norm. X-Ray fluorescence (XRF) was used to determine the element composition...
December 2016: European Journal of Paediatric Dentistry: Official Journal of European Academy of Paediatric Dentistry
Viktor A Vorozhtcov, Valentina L Stolyarova, Sergey I Lopatin, Sergey M Shugurov, Andrey L Shilov, Vladimir F Sapega
RATIONALE: The Bi2 O3 -P2 O5 -SiO2 system possesses a number of valuable properties that may be of use for various practical applications, both for obtaining new materials, e.g. optical fibers, and for replacing systems based on toxic lead silicate. Information on vaporization processes and thermodynamic properties obtained in the present study will be useful for the development of synthetic methods and approaches for modeling the thermodynamic properties of materials based on this system...
January 15, 2017: Rapid Communications in Mass Spectrometry: RCM
Liudmila D Iskhakova, Filipp O Milovich, Valery M Mashinsky, Alexander S Zlenko, Sergey E Borisovsky, Evgeny M Dianov
The nature of nanocrystalline inclusions and dopant distribution in bismuth-doped silicate fibers and preforms are studied by scanning and transmission electron microscopy, and energy and wavelength-dispersive X-ray microanalysis. The core compositions are Bi:SiO2, Bi:Al2O3-SiO2, Bi:GeO2-SiO2, Bi:Al2O3-GeO2-SiO2, and Bi:P2O5-Al2O3-GeO2-SiO2. Nanocrystals of metallic Bi, Bi2O3, SiO2, GeO2, and Bi4(GeO4)3 are observed in these glasses. These inclusions can be the reason for the background optical loss in bismuth-doped optical fibers...
September 26, 2016: Microscopy and Microanalysis
Linling Tan, Liping Wang, Mingying Peng, Shanhui Xu, Qinyuan Zhang
For application of bismuth laser glasses in either fiber amplifier or laser, their performance stability in long run should be understood especially in extreme conditions. However, so far, there are few reports on it. Here, we found, after the cycle experiments on heating and cooling, that the proper increase of lithium content in lithium tantalum silicate laser glass can lead to unusual anti-thermal degradation of bismuth NIR luminescence, which completely differs from the scenario in germanate glass. FTIR, <sup>29</sup>Si MAS NMR spectra, absorption and dynamic photoluminescence spectra are employed to unravel how this happens...
August 8, 2016: Optics Express
V Thomas, R G S Sofin, M Allen, H Thomas, P R Biju, G Jose, N V Unnikrishnan
Samarium doped sodium bismuth silicate glass was synthesized using the melt quenching method. Detailed optical spectroscopic studies of the glassy material were carried out in the UV-Vis-NIR spectral range. Using the optical absorption spectra Judd-Ofelt (JO) parameters are derived. The calculated values of the JO parameters are utilized in evaluating the various radiative parameters such as electric dipole line strengths (Sed ), radiative transition probabilities (Arad ), radiative lifetimes (τrad ), fluorescence branching ratios (β) and the integrated absorption cross- sections (σa ) for stimulated emission from various excited states of Sm3+ ‡ ion...
January 15, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Juliane Maria Guerreiro-Tanomaru, Fernando Antonio Vázquez-García, Roberta Bosso-Martelo, Maria Inês Basso Bernardi, Gisele Faria, Mario Tanomaru
OBJECTIVE: Mineral Trioxide Aggregate (MTA) is a calcium silicate cement composed of Portland cement (PC) and bismuth oxide. Hydroxyapatite has been incorporated to enhance mechanical and biological properties of dental materials. This study evaluated physicochemical and mechanical properties and antibiofilm activity of MTA and PC associated with zirconium oxide (ZrO2) and hydroxyapatite nanoparticles (HAn). MATERIAL AND METHODS: White MTA (Angelus, Brazil); PC (70%)+ZrO2 (30%); PC (60%)+ZrO2 (30%)+HAn (10%); PC (50%)+ZrO2 (30%)+HAn (20%) were evaluated...
May 2016: Journal of Applied Oral Science: Revista FOB
Sergei V Firstov, Sergey V Alyshev, Konstantin E Riumkin, Vladimir F Khopin, Alexey N Guryanov, Mikhail A Melkumov, Evgeny M Dianov
It is now almost twenty-five years since the first Erbium-Doped Fiber Amplifier (EDFA) was demonstrated. Currently, the EDFA is one of the most important elements widely used in different kinds of fiber-optic communication systems. However, driven by a constantly increasing demand, the network traffic, growing exponentially over decades, will lead to the overload of these systems ("capacity crunch") because the operation of the EDFA is limited to a spectral region of 1530-1610 nm. It will require a search for new technologies and, in this respect, the development of optical amplifiers for new spectral regions can be a promising approach...
2016: Scientific Reports
Christian A Dettwiler, Mirella Walter, Lucia K Zaugg, Patrik Lenherr, Roland Weiger, Gabriel Krastl
BACKGROUND/AIMS: Traumatized teeth requiring endodontic intervention may discolor as a result of the treatment performed. Thus, the aim was to investigate the discoloration potential of different endodontic cements, dressings, and irrigants used in dental traumatology. MATERIALS AND METHODS: Cylindrical cavities were prepared in 330 bovine enamel-dentine blocks (10 × 10 × 3.5 mm), leaving 2 mm of enamel and dentine on the labial side. The specimens were randomly assigned to 22 groups (n = 15)...
December 2016: Dental Traumatology: Official Publication of International Association for Dental Traumatology
Gonggong Lu, Kehui Qiu, Junfeng Li, Wentao Zhang, Xiqiang Yuan
A series of novel red-emitting Sm(3)(+) -doped bismuth silicate phosphors, Bi4 Si3 O12 :xSm(3)(+) (0.01 ≤ x ≤ 0.06), were prepared via the sol-gel route. The phase of the synthesized samples calcinated at 800 °C is isostructural with Bi4 Si3 O12 according to X-ray diffraction results. Under excitation with 405 nm light, some typical peaks of Sm(3)(+) ions centered at 566, 609, 655 and 715 nm are found in the emission spectra of the Sm(3)(+) -doped Bi4 Si3 O12 phosphors. The strongest peak located at 609 nm is due to (4) G5/2 -(6) H7/2 transition of Sm(3)(+) ...
February 2017: Luminescence: the Journal of Biological and Chemical Luminescence
Shahbaz Khan, Muhammad Kaleem, Muhammad Amber Fareed, Amir Habib, Kefi Iqbal, Ayesha Aslam, Shahab Ud Din
The purpose of this study was to investigate the chemical composition and particle morphology of white mineral trioxide aggregate (WMTA) and two white Portland cements (CEM 1 and CEM 2). Compositional analysis was performed by energy dispersive X-ray spectroscopy, X-ray fluorescence spectrometry and X-ray diffraction whereas, morphological characteristics were analyzed by scanning electron microscope and Laser scattering particle size distribution analyzer. The elemental composition of WMTA, CEM 1 and CEM 2 were similar except for the presence of higher amounts of bismuth in WMTA...
2016: Dental Materials Journal
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"