Correlation between Microstructure and Magnetic Properties on MnZn Ferrite with Bi2O3 Increasing Addition

2014 ◽  
Vol 216 ◽  
pp. 23-28
Author(s):  
Mihai Branzei ◽  
Ionut Cristea ◽  
Ion Ciuca ◽  
Adrian Bibiș ◽  
Marcel Feder
Keyword(s):  
Ball Mill ◽  
Raw Materials ◽  
Steel Ball ◽  
Ceramic Technology ◽  
Molar Ratio ◽  
Quantitative Characterization ◽  
Mnzn Ferrite ◽  
Sintered Powder ◽  
Microstructure And Magnetic Properties

The aim of this paper is quantitative characterization of a MnZn ferrite with Bi2O3increasing addition using the Image-Pro Plus software from Media Cybernetics. The sample matrix is a ferrite with the following chemical composition: Mn0.54Zn0.37Fe2.06O4. We applied the conventional ceramic technology in order to obtain the samples. Thus, the raw materials, i.e. αFe2O3, Mn3O4, and ZnO, in a molar ratio 53:28:19 were mixed in suitable proportions in a steel ball-mill using demineralized water. The mixture was burn off at 800 °C for 1 hour, in air. The pre-sintered powder was milled in steel ball-mill with increasing addition of Bi2O3(0.00, 0.01, 0.03, 0.05, 0.07, 0.10, 0.30, 0.50 wt %). For quick references, the sample without bismuth ions was denoted and the samples with increasing concentrations were numbered from 1, 7.

Synthesis and Characterization of Super-Molecular Ionic Liquids

2011 ◽  
Vol 197-198 ◽  
pp. 906-910
Author(s):  
Hui Ru Liu ◽  
Li Qiang Lv ◽  
Xing Chen Zhang
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Melting Point ◽  
Quantum Chemical ◽  
Organic Molecules ◽  
Raw Materials ◽  
Ammonium Thiocyanate ◽  
Molar Ratio ◽  
Molecular Ion

This study concerned a novel super-molecular ionic liquid synthesized by ammonium thiocyanate and caprolactam. The physical characters such as melting point and electric conductivity were investigated. Results showed that the melting point is -12.2°C at the molar ratio of 3:1 (caprolactam/ammonium thiocyanate), which is much lower than raw materials. The electric conductivities of synthesized ionic liquids were close to that of imidazole ILs. The structure of ionic liquid was characterized by IR,1HNMR and quantum chemical calculations. It was shown that the NH4+cation connected with caprolactam organic molecules by hydrogen bonds, leading to the forming of a super-molecular ion. The electrostatic attraction of super-molecular ion with anion was decreased because of the larger volume of super-molecular ion than original cation, thus the melting point decreased. The key properties that distinguish super-molecular ionic liquid from other ILs were the presence of supermolecular ion, which can be used to build up a hydrogen-bonded network. This type ion liquid was named as super-molecular ion liquid.

Solvothermal Synthesis and Luminescence Properties of Gd2O2S:RE3+ (RE3+=Eu3+/Tb3+) Hollow Sphere

2019 ◽  
Vol 807 ◽  
pp. 1-10 ◽  
Author(s):  
Guang Xi Xu ◽  
Xiao Tong Sang ◽  
Jing Bao Lian ◽  
Nian Chu Wu ◽  
Xue Zhang
Keyword(s):  
Solvothermal Synthesis ◽  
Solvothermal Method ◽  
Raw Materials ◽  
Hollow Spheres ◽  
Hollow Structure ◽  
Molar Ratio ◽  
Detailed Characterization ◽  
X Ray ◽  
Electronic Microscope

Eu3+ and Tb3+ ions singly activated Gd2O2S hollow spheres have been successfully synthesized via solvothermal method by using Gd (NO3)3, Eu (NO3)3, Tb (NO3)3 and thiourea as raw materials. Detailed characterization of the as-prepared samples were obtained by X-ray diffractometry (XRD), field emission scanning electron microscopy (FE-SEM), transmission electronic microscope (TEM) and photoluminescence (PL) spectroscopy. The results demonstrate that at 220 oC for 24 h, the molar ratio of thiourea/Gd3+ has no significant impact on the phase composition of Gd2O2S products. With the reaction time increased from 6 h to 24 h, the morphology of Gd2O2S samples changed from ellipsoidal to near-spheroidal structure, but still remained hollow structure. PL results show that the strongest emission peaks for Gd2O2S:Eu3+ and Gd2O2S:Tb3+ samples were centered at 625 nm and 545 nm, corresponding to the 5D0→7F2 transition of Eu3+ ions and 5D4→7F5 transition of Tb3+ ions, respectively. The quenching concentrations for Eu3+ and Tb3+ ions were 12% and 6%, which can be attributed to the exchange interaction for Eu3+ and Tb3+ ions, respectively.

Preparation and Characterization of Hyperbranched Silicone Oil by Hydrosilylation Reaction

2013 ◽  
Vol 395-396 ◽  
pp. 363-366
Author(s):  
Zhu Liu ◽  
Hua Shi Liu ◽  
Rui Fang Guan ◽  
Chuan Jian Zhou
Keyword(s):  
Dynamic Viscosity ◽  
High Performance ◽  
Silicone Oil ◽  
Raw Materials ◽  
Molar Ratio ◽  
Straight Chain ◽  
Hydrosilylation Reaction ◽  
H Nmr ◽  
Structures And Properties

Hyperbranched silicone oil was prepared using low-polyhydrosiloxane and vinyl terminated methylphenyl silicone oil as the raw materials through hydrosilylation reaction. The structures and properties of hyperbranched silicone oil were characterized through 1H NMR, TG and dynamic viscosity. The influence on synthesis of hyperbranched silicone oil was discussed, which was caused by ratio of different raw materials. When molar ratio of Si-H bond and Si-Vi bond of raw materials was 3.5:1 (mol), the reaction degree of hyperbranched silicone oils double bond was as high as 80%. At room temperature and 100°C, comparing the dynamic viscosity of hyperbranched silicone oil and straight chain silicone oil, we found that viscosity decrease rate of hyperbranched silicone oil was obviously lower. TG curve of hyperbranched silicone oil and straight chain silicone oil also certified that the hyperbranched silicone oil has higher thermal stability than the straight chain phenyl silicone oil. Therefore hyperbranched silicone oil is more suitable for the preparation of high-performance elastic clay than straight chain silicone oil.

Synthesis and Characterization of Zn-Ca-Mg-Al Hydrotacite-Like Compounds and its Application in the PVC

2011 ◽  
Vol 66-68 ◽  
pp. 65-69
Author(s):  
Long Feng Li ◽  
Yuan Gao ◽  
Mao Lin Zhang
Keyword(s):  
Reaction Time ◽  
Ph Value ◽  
Raw Materials ◽  
Treatment Temperature ◽  
Molar Ratio ◽  
Medium Ph ◽  
X Ray ◽  
Ft Ir ◽  
Thermal Stability Of

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n(Zn+Mg+Ca):n(Al) =2. The products synthesized were applied to PVC to improve the thermal stability of PVC.

scholarly journals Topological Features of the Alluaudite-Type Framework and Its Derivatives: Synthesis and Crystal Structure of NaMnNi2(H2/3PO4)3

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 237
Author(s):  
Sergey M. Aksenov ◽  
Natalia A. Yamnova ◽  
Natalia A. Kabanova ◽  
Anatoly S. Volkov ◽  
Olga A. Gurbanova ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Topological Analysis ◽  
Structure Type ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Quantitative Characterization ◽  
Synthesis And Crystal Structure ◽  
Topological Features ◽  
Nickel Phosphate

A new sodium manganese-nickel phosphate of alluaudite supergroup with the general formula NaMnNi2(H2/3PO4)3 was synthesized by a hydrothermal method. The synthesis was carried out in the temperature range from 540 to 660 K and at the general pressure of 80 atm from the oxides mixture in the molar ratio MnCl2: 2NiCl2: 2Na3PO4: H3BO3: 10H2O. The crystal structure was studied by a single-crystal X-ray diffraction analysis: space group C2/c (No. 15), a = 16.8913(4), b = 5.6406(1), c = 8.3591(3) Å, β = 93.919(3), V = 794.57(4) Å3. The compound belongs to the alluaudite structure type based upon a mixed hetero-polyhedral framework formed by MX6-octahedra and TX4-tetrahedra. The characteristic feature of the title compound is the absence of cations or H2O molecules in channel II, while the negative charge of the framework is balanced by the partial protonation of PO4 tetrahedra. The presence of the transition metals at the A-type sites results in the changes of stoichiometry and the local topological features. Topological analysis of the hetero-polyhedral alluaudite-type frameworks and its derivatives (johillerite-, KCd4(VO4)3-, and keyite-type) and quantitative characterization of their differences was performed by means of natural tilings.

Sintering and Characterization of Calcium Phosphate Biomaterials Elaborated from Fossilized Calcareous Shell

2014 ◽  
Vol 936 ◽  
pp. 701-706
Author(s):  
Daiara F. Silva ◽  
Nelson Heriberto Almeida Camargo ◽  
Nelson Levandowski ◽  
Priscila F. Franczak ◽  
Mônica S. Schneider
Keyword(s):  
Calcium Phosphate ◽  
Open Porosity ◽  
Raw Materials ◽  
Microstructural Characterization ◽  
Bone Substitutes ◽  
Molar Ratio ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

Bioceramics of calcium phosphate, obtained from natural raw materials, are promising as bone substitutes because they exhibit crystallographic similarity with the bone tissue. This work deals with the sintering and characterization of calcium phosphate biomaterials from fossilized calcareous shells. Four compositions of biomaterials were prepared with Ca/P molar ratio ranging from 1.4 to 1.67. They were synthesized using a wet method and calcined at 900°C/2h providing calcium phosphate powder, then compressed into a metallic mould. The samples obtained from this compression were sintered at 1200oC for 2h. The biomaterials recovered from sintering were subjected to a microstructural characterization by scanning electron microscopy [SE and by X-ray diffraction [XR. Mechanical properties were determined by compression tests. Finally, the Arthur method was used for determining the hydrostatic density and open porosity from these biomaterials. The value of fracture strength was between 54 and 84 MPa for compositions 1.5, 1.67 and 1.6 molar and for composition 1.4 molar about 328 Mpa. The results also showed was the amount of open porosity which ranged between 35 and 54% with increasing Ca/P molar ratio. These studies demonstrate that the production of biomaterials from fossilized calcareous shells may be a new alternative to the production of biomaterials for bone reconstruction.

scholarly journals A multitechnique, quantitative characterization of the pore space of fired bricks made of five clayey raw materials used in European brick industry

2021 ◽  
Vol 200 ◽  
pp. 105884
Author(s):  
Thomas Buchner ◽  
Thomas Kiefer ◽  
Luis Zelaya-Lainez ◽  
Wolfgang Gaggl ◽  
Thomas Konegger ◽  
...  
Keyword(s):  
Raw Materials ◽  
Pore Space ◽  
Quantitative Characterization ◽  
Fired Bricks ◽  
Materials Used

scholarly journals Characterization of Islamic Ceramic Production Techniques in Northeast Iberian Peninsula: The Case of Medieval Albarracin (Spain)

2021 ◽  
Vol 11 (16) ◽  
pp. 7212
Author(s):  
Josefina Pérez-Arantegui ◽  
Paz Marzo
Keyword(s):  
Iberian Peninsula ◽  
Raw Materials ◽  
Optical Emission ◽  
Ceramic Technology ◽  
Emission Spectrometry ◽  
12Th Century ◽  
Production Techniques ◽  
Main Components ◽  
Different Sources

Ceramic objects found in the Islamic Taifa of Albarracin (Spain), 12th century CE, were studied to ascertain the main characteristics and influences of its manufacture. Production centers even from small kingdoms can add new insights in medieval ceramic technology. Several types of decorated ceramics, such as tin-opacified glazed, monochrome glazed and cuerda seca, were investigated. Ceramic bodies were analyzed by ICP-Optical Emission Spectrometry, and glazes were studied by Scanning Electron Microscopy with Energy Dispersive X-ray Spectrometry. All the ceramic bodies showed the use of Ca-rich pastes, although three groups could be distinguished and related to their decoration. Lead and silicon were the main components of the glazes, as well as scattered tin oxide in the case of white or green opacified glazes. Some features, such as calcareous bodies, double firing for tin-opacified glazes, glaze components, and coloring oxides, were common in Albarracin samples and other Islamic production centers in the Iberian Peninsula. However, some differences were also highlighted in lead/silica proportions and cuerda seca decoration, and several influences from northern or southern pottery centers. Lead isotope ratios, measured by ICP-Quadrupole Mass Spectrometry, revealed two different sources or suppliers of lead raw materials according to the type of glaze to be prepared.

Hydrothermal Synthesis and Characterization of Ca-Mg-Al Hydrotacite-Like Compounds

2011 ◽  
Vol 287-290 ◽  
pp. 569-572 ◽  
Author(s):  
Mao Lin Zhang ◽  
Yuan Gao ◽  
Long Feng Li
Keyword(s):  
Reaction Time ◽  
Ph Value ◽  
Raw Materials ◽  
Treatment Temperature ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Medium Ph ◽  
X Ray ◽  
Ft Ir

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n (Mg+Ca): n (Al) = 1~3 and n (Mg): n (Ca) = 1~3.

Sign in / Sign up

Export Citation Format

Share Document