Structural and morphological features of MgO powders. The key role of the preparative starting compound

1998 ◽  
Vol 13 (8) ◽  
pp. 2218-2223 ◽  
Author(s):  
S. Ardizzone ◽  
C. L. Bianchi ◽  
B. Vercelli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Specific Surface ◽  
Surface Area ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Starting Compound ◽  
Scanning Electron

The present paper reports data concerning magnesia samples obtained by calcination of different precursor salts at different increasing temperatures (873–1253 K). The oxides are characterized by x- ray diffraction, scanning electron microscopy, and N2 adsorption at subcritical temperatures. The samples appear to be composed, at any temperature, of pure periclase with a degree of crystallinity which increases with the temperature of calcination. Morphologically, the products have the shape either of lamellas or of cubes of variable dimensions, depending on the nature and route of preparation of the precursor salts. The variation of the specific surface area and the degree of porosity with the nature of the precursors and the temperature is discussed.

scholarly journals Nanomaterial identification of powders: comparing volume specific surface area, X-ray diffraction and scanning electron microscopy methods

2019 ◽  
Vol 6 (1) ◽  
pp. 152-162 ◽  
Author(s):  
Claire Dazon ◽  
Olivier Witschger ◽  
Sébastien Bau ◽  
Vanessa Fierro ◽  
Philip L. Llewellyn
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
X Ray Diffraction ◽  
Reliable Criterion ◽  
X Ray ◽  
Area X ◽  
Scanning Electron

This work shows that the volume specific surface area could be a reliable criterion for nanomaterial identification.

Effect of Zn on the intermetallics formation and reliability of Sn-3.5Ag solder on a Cu pad

2007 ◽  
Vol 22 (7) ◽  
pp. 1879-1887 ◽  
Author(s):  
Y.K. Jee ◽  
Y.H. Ko ◽  
Jin Yu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Isothermal Aging ◽  
X Ray Diffraction ◽  
X Ray ◽  
Drop Tests ◽  
Joint Microstructures ◽  
Role Of Zn ◽  
Scanning Electron

Varying amounts of Zn (1, 3, and 7 wt%) were added to Sn–3.5Ag solder on a Cu pad, and the resultant solder joint microstructures after a reflow and isothermal aging (150 °C, up to 500 h) were investigated using scanning electron microscopy, energy dispersive x-ray, and x-ray diffraction, which were subsequently correlated to the results of microhardness and drop tests. Zinc was effective in improving the drop resistance of Sn–3.5Ag solder on the Cu pad, and an addition of 3 wt% Zn nearly doubled the number of drops-to-failure (Nf). The beneficial role of Zn was ascribed to suppression of Cu6Sn5 and precipitation of Zn-containing intermetallic compounds (IMCs). However, the Zn effect was reduced as Cu6Sn5 and Ag3Sn precipitated in a joint IMC layer after prolonged aging. The interface between Ag5Zn8 and Cu5Zn8 was resistant to drop impact, but two other layered IMC structures of Cu6Sn5/Cu3Sn and Cu5Zn8/Cu6Sn5 were not.

Regeneration of the Brewing Spent Diatomite

2014 ◽  
Vol 998-999 ◽  
pp. 1425-1428 ◽  
Author(s):  
Wen Ya Mei ◽  
Teng Hong Hui
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Surface Area ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
X Ray ◽  
Remarkable Increase ◽  
Efficient Adsorbent ◽  
Scanning Electron

Brewing spent diatomite (BSDT), a beer industrial by-product, was regenerated with calcination. The characteristics of regenerated BSDT were detected by X-ray diffraction, X-ray fluorescence, Fourier-transform infrared, and scanning electron microscopy. The results showed that the mineralization of the surface adsorbate and the remarkable increase in the Si-OH decreased the pHpzc value from 7.6 to 5.2 and increased the surface area from 36 m2/g to 52 m2/g after calcination at 800 °C. The results show that the regenerated BSTD could be employed as an efficient adsorbent for the recycling of BSDT.

Effects of dry grinding on pyrophyllite

Clay Minerals ◽  
1988 ◽  
Vol 23 (4) ◽  
pp. 399-410 ◽  
Author(s):  
J. L. Pérez-Rodríguez ◽  
L. Madrid Sánchez del Villar ◽  
P.J. Sánchez-Soto
Keyword(s):  
Electron Microscopy ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Grinding Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dry Grinding ◽  
Scanning Electron ◽  
Area Data

AbstractDry grinding of pyrophyllite (Hillsboro, USA) has been studied by X-ray diffraction (XRD), specific surface area measurements (BET) and scanning electron microscopy (SEM). At the beginning of the grinding process, some effects such as delamination, gliding and folding of the layers, and decrease in particle size were detected by SEM and XRD, resulting in a large increase in specific surface area, up to a maximum of ∼60 m2·g−1. Marked changes in the structure take place between 30 and 32 mins grinding. Longer grinding times increase the degree of disorder and SEM and specific surface area data suggest that aggregation occurs. XRD results indicate that some residual order persists in the degraded structure.

Synthesis of Coal Dust Depressor and its Application in Preventing Coal Dust

2012 ◽  
Vol 482-484 ◽  
pp. 2301-2306 ◽  
Author(s):  
Fang Qin Cheng ◽  
Shu Yan Cheng ◽  
Yan Xia Guo ◽  
Li Qiong Cao
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Coal Dust ◽  
Raw Material ◽  
Surface Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Stock Pile ◽  
Scanning Electron

A novel coal dust depressor was prepared by alkalization and etherficayion reactions using wastepaper as raw material. The sample was characterized by means of FTIR spectroscopy (FTIR)、scanning electron microscopy (SEM)、X-ray diffraction (XRF) and viscometer measurements. The coal dust inhibitor was developed to suppress flying dust over coal dump and conveyor. The result shows that flying coal dust was prevented by intrinsic viscosity of coal dust depressor which was sprayed on the surface stock pile can make the surface material bond with each other to form layer of crust, having a role of dust prevention. Application of the coal dust depressor can reduce the losses of coal and protect the environment from being polluted.

scholarly journals The Role of Chemical Substitutions on Bi-2212 Superconductors

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 462 ◽  
Author(s):  
Riccardo Cabassi ◽  
Davide Delmonte ◽  
Muna Mousa Abbas ◽  
Ali Razzak Abdulridha ◽  
Edmondo Gilioli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Critical Temperature ◽  
High Temperature Superconductor ◽  
X Ray Diffraction ◽  
Structural Morphology ◽  
X Ray ◽  
Critical Temperature Tc ◽  
Scanning Electron

We present a study on the correlation of the superconducting critical temperature (Tc) and structural morphology with a chemically substituted high-temperature superconductor (HTS) (Bi,Pb)-2212 via Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), and d c magnetometry. The elements Zn, Y, Ti, and Nd are incorporated within the bismuth cuprate structure at amounts that extend the ranges currently found in literature.

Sintering Sr2MgWO6 Ceramic and their Reactivity to Petroleum

2014 ◽  
Vol 798-799 ◽  
pp. 154-159 ◽  
Author(s):  
José Carlos da Silva Oliveira ◽  
Ricardo Arthur Sanguinetti Ferreira ◽  
Yogendra Prasad Yadava
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermogravimetric Analysis ◽  
Specific Surface ◽  
Ball Mill ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Microhardness ◽  
Scanning Electron

This work has as main objectives to produce the ceramic Sr2MgWO6and evaluate their reactivity to petroleum. Powders of SrCO3, MgO and WO3were selected, taken in stoichiometric amounts and synthesized by conventional route. The synthesis was characterized by size distribution, specific surface area and thermogravimetric analysis (TGA). The synthesis was also fragmented into ball mill and characterized by specific surface. It was compacted, then was calcined at 1200 °C and analyzed by X-ray diffraction. The powders Sr2MgWO6with perovskite structure were compacted and sintered at 1250, 1300 and 1350 °C. The materials produced were evaluated by microhardness, scanning electron microscopy (SEM), diffraction of X-rays and tests submersion in petroleum. The results showed that the ceramics have high microhardness and potential to be used in chemically aggressive environments such as petroleum.

A Comparative Study on Preparation of TiO2 Pellets as Photocatalysts Based on Different Precursors

2005 ◽  
Vol 475-479 ◽  
pp. 4165-4170 ◽  
Author(s):  
Yong Gang Luo ◽  
Linda Zou ◽  
Eric Hu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Area ◽  
Sintering Temperature ◽  
Temperature Reaction ◽  
Surface Porosity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Titania Powder ◽  
Scanning Electron

The porous TiO2 pellets were prepared based on pigment grade titaina, P25 titania powder and titanium(IV) butoxide. The characterization was done with X-Ray diffraction, scanning electron microscopy and BET measurements. The result shows that TiO2 pellets by using titanium(IV) butoxide with some addictive have the best surface porosity, with specific surface area of 196.9m2/g. For pigment grade titania and P25 titania powder, it is still effective to enhance the surface area after reassembling. The surface area increased from 11.6 to 29.2 m2/g for pigment grade titania and from 50 to 84.4 m2/g for P25 titania powder. Furthermore, it has been investigated on how to optimize and get the highest surface area by controlling the sintering temperature, reaction temperature, pH of solution, and the amount of alcohol and addictive of surfactant during preparation. The experimental photocatalytic degradation of acetone and toluene was performed using titania pellets made from P25 titania powder.

scholarly journals Effect of KOH Activator on the Performance of Activated Carbon from Oil Palm Kernel Shell as Supercapacitor Electrode Material

2020 ◽  
Vol 9 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Yola Azli Perdana ◽  
Rahma Joni ◽  
Emriadi Emriadi ◽  
Hemansyah Aziz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Activated Carbon ◽  
Surface Area ◽  
Palm Kernel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Palm Kernel Shell ◽  
Scanning Electron

Karbon aktif dari cangkang kelapa sawit sebagai bahan elektroda superkapasitor telah diteliti. Superkapasitor dirangkai dengan metoda plat/sandwich yang dipisahkan oleh separator. Untuk mendapatkan nilai kapasitansi yang besar dilakukan variasi jumlah aktivator terhadap karbon menggunakan aktivator KOH. Sifat fisikokimia dari karbon aktif diteliti dengan melakukan karakterisasi menggunakan XRD (X-Ray Diffraction), SEM-EDX (Scanning Electron Microscopy-Energy Dispersive X-Ray) dan SAA (Surface Area Analyzer) dan sifat elektrokimianya diteliti dengan pengukuran CV (Cyclic Voltammetry). Karbon aktif dengan perbandingan 1:5 memiliki luas permukaan yang paling besar yaitu 793,326 m2/g dan nilai kapasitansi spesifik tertinggi yaitu 99,151 F/g. The activated carbon from oil palm kernel shell as an electrode material for supercapacitors has been investigated. The supercapasitor was assembled by plate/sandwich methods. Both electrodes were separated by using a separator. To increase the capacitancy value, variations in the number of activators on carbon were carried out using KOH activator. The physicochemical properties of activated carbon were investigated by characterizing using XRD (X-Ray Diffraction), SEM-EDX (Scanning Electron Microscopy-Energy Dispersive X-Ray) and SAA (Surface Area Analyzer) and the electrochemical properties were investigated by measuring CV (Cyclic Voltammetry). Activated carbon with a ratio of 1:5 has the largest surface area of 793,326 m2/g and the highest specific capacitance value is 99,151 F/g.Keywords: activated carbon, supercapasitor, activator, surface area, specific capacitance

scholarly journals Synthesis of High-Purity SnO2Nanobelts by Using Exothermic Reaction

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Guodong Zhang ◽  
Nian Liu ◽  
Zhengyuan Ren ◽  
Bing Yang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Purity ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Rutile Structure ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

This paper presents a new method to synthesize high-purity single-crystalline SnO2nanobelts with rutile structure. The purity, morphology, crystal structure, and sizes of the as-grown SnO2nanobelts are characterized by X-ray diffraction, energy-dispersive X-ray analysis, scanning electron microscopy, transmission electron microscopy, and Raman-scattering spectroscopy. The scanning electron microscopy and transmission electron microscopy reveal tetragonal SnO2nanobelts of 50–120 nm in width, 20–50 nm in thickness, and 2–10 μm in length. The three observed Raman peaks at 475, 633, and 774 cm−1indicate the typical rutile structure of the SnO2, which is in agreement with the X-ray diffraction results, and other peaks of impurity are not found. High-resolution transmission electron microscopy demonstrates that the nanobelts have a high degree of crystallinity, without typical imperfects in it. And the growth mechanism of the SnO2nanobelts is discussed.

Sign in / Sign up

Export Citation Format

Share Document