Silicon −29 Solids NMR-MAS Characterization of Non-Oxide Powders and Fibers

1986 ◽  
Vol 73 ◽  
Author(s):  
Kenneth E. Inkrott ◽  
Stephen M. Wharry ◽  
Dan J. O'Donnell
Keyword(s):  
Raw Materials ◽  
Synthesis Process ◽  
Ceramic Fibers ◽  
X Ray Diffraction ◽  
Oxide Powders ◽  
Ceramic Synthesis ◽  
Structural Details ◽  
Size Characterization ◽  
Xrd Patterns

ABSTRACTPowder x-ray diffraction has been the most common method for rapid structural analysis and identification of crystalline ceramic raw materials. However, new structural ceramic raw materials often have linebroadened or featureless XRD patterns due to structural strain or small crystallite size. Characterization of various silicon carbide and silicon nitride powders and ceramic fibers by Si-29 NMR-MAS spectroscopy has revealed structural details and differences in these materials previously indistinguishable by XRD or other routine methods. Unique variables intrinsic to a given ceramic synthesis process are reflected in the NMR-MAS spectra of the resulting products.

Synthesis and Characterization of Cu-10-20wt%Ni Nanopowders by a Chemical Precipitation Route

2012 ◽  
Vol 16 ◽  
pp. 141-151
Author(s):  
R. Roohibakhsh ◽  
Hamid Reza Rezaie ◽  
Hekmat Razavizadeh
Keyword(s):  
Sodium Hydroxide ◽  
Raw Materials ◽  
Nickel Sulfate ◽  
Sulfate Solution ◽  
Chemical Precipitation ◽  
Hydrogen Atmosphere ◽  
X Ray Diffraction ◽  
Oxide Powders ◽  
Chemical Procedure

In this research Cu-Ni nanostructure powders were prepared by using a chemical procedure including initial precipitating, calcining the precipitates and reducing the calcined powders. The influence of nickel contents on the characteristics of the synthesized powders was investigated. Copper and nickel sulfate and sodium hydroxide were used as raw materials. CuSO4.3Cu(OH)2, NiOOH and Ni(OH)2 precipitates were obtained by addition of sodium hydroxide into aqueous copper and nickel sulfate solution. Oxide powders were produced by calcinations of precipitates. Considering the information obtained from the TGA test, calcination was done on precipitates. Copper-nickel nanostructure powders were synthesized by reduction of calcined powders in a hydrogen atmosphere. Eventually powders were characterized by using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Crystallite size of final synthesized powders was in the range of 30 to 33 nm.

Microstructure Characterization of Metal Mixed Oxides

MRS Advances ◽  
2017 ◽  
Vol 2 (64) ◽  
pp. 4025-4030 ◽  
Author(s):  
T. Kryshtab ◽  
H. A. Calderon ◽  
A. Kryvko
Keyword(s):  
Mixed Oxides ◽  
Profile Analysis ◽  
Atomic Resolution ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Reconstruction Procedure ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Co Precipitation

ABSTRACTThe microstructure of Ni-Mg-Al mixed oxides obtained by thermal decomposition of hydrotalcite-like compounds synthesized by a co-precipitation method has been studied by using X-ray diffraction (XRD) and atomic resolution transmission electron microscopy (TEM). XRD patterns revealed the formation of NixMg1-xO (x=0÷1), α-Al2O3 and traces of MgAl2O4 and NiAl2O4 phases. The peaks profile analysis indicated a small grain size, microdeformations and partial overlapping of peaks due to phases with different, but similar interplanar spacings. The microdeformations point out the presence of dislocations and the peaks shift associated with the presence of excess vacancies. The use of atomic resolution TEM made it possible to identify the phases, directly observe dislocations and demonstrate the vacancies excess. Atomic resolution TEM is achieved by applying an Exit Wave Reconstruction procedure with 40 low dose images taken at different defocus. The current results suggest that vacancies of metals are predominant in MgO (NiO) crystals and that vacancies of Oxygen are predominant in Al2O3 crystals.

scholarly journals Synthesis and Characterization of Sugarcane Bagasse Based Activated Carbon: Effect of Impregnation Ratio of ZnCl2

2020 ◽  
Vol 41 (1) ◽  
pp. 74-79
Author(s):  
Sahira Joshi ◽  
Bishnu K.C.
Keyword(s):  
Iodine Number ◽  
Surface Area ◽  
Sugarcane Bagasse ◽  
Amorphous Materials ◽  
Activated Carbons ◽  
X Ray Diffraction ◽  
Impregnation Ratio ◽  
Methylene Blue Number ◽  
Xrd Patterns

Series of activated carbons (ACs) have been prepared from Sugarcane bagasse powder by ZnCl2 activation at various impregnation ratios of ZnCl2 to Sugarcane bagasse powder of 0.25:1, 0.5:1, 1:1 and 2:1 by weight. Characteristics of the activated carbons (ACs) were determined by iodine number, methylene blue number, surface area, scanning electron microscopy (SEM) and x-ray diffraction. Iodine number (IN) indicated that, microporosity of the AC were increased with increasing impregnation ratio ZnCl2 to Sugarcane bagasse upto 1:1 then started to decrease. However, mesoporosity as well as surface area was increased progressively. The maximum value of iodine number (868 mg/g) was achieved in the AC prepared at impregnation ratio of ZnCl2 to sugarcane bagasse 1:1. SEM micrographs also show the presence of well developed pores on its surface of AC-1. The broad peaks in the XRD patterns indicated that, all the ACs is amorphous materials. From results, it is concluded that ZnCl2 concentration used in impregnation is effective for development of porosity and surface area of the AC prepared from Sugarcane bagasse.

Morphology and Crystallographic Characterization of Nickel Nanowires—Influence of Magnetic Field and Current Density During Synthesis

2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Mahendran Samykano ◽  
Ram Mohan ◽  
Shyam Aravamudhan
Keyword(s):  
Magnetic Field ◽  
Current Density ◽  
Quality Data ◽  
Synthesis Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nickel Nanowires ◽  
Helium Ion ◽  
Sem Imaging

This paper presents results and discussion from a comprehensive morphological and crystallographic characterization of nickel nanowires synthesized by template-based electrodeposition method. In particular, the influence of magnetic and electric field (current density) conditions during the synthesis of nickel nanowires was studied. The structure and morphology of the synthesized nanowires were studied using Helium ion microscopy (HIM) and scanning electron microscopy (SEM) methods. The HIM provided higher quality data and resolution compared to conventional SEM imaging. The crystallographic properties of the grown nanowires were also studied using X-ray diffraction (XRD). The results clearly indicated that the morphological and crystallographic properties of synthesized nickel nanowires were strongly influenced by the applied magnetic field and current density intensity during the synthesis process.

Preparation and Characterization of Ionic Liquild Modified Clay and its Application in Polypropylene/Clay Nanocomposites

2011 ◽  
Vol 55-57 ◽  
pp. 1588-1592
Author(s):  
Li Mei Wang
Keyword(s):  
Clay Nanocomposites ◽  
X Ray Diffraction ◽  
Modified Clay ◽  
Solution Blending ◽  
Organically Modified ◽  
Result Show ◽  
Xrd Patterns ◽  
Clay Layers ◽  
Poly Propylene

Clay was organically modified with one kind of ionic liquild. Organical clay obtained was used to prepare poly(propylene) (PP)/clay nanocomposites by solution blending. Flourier transform infrared (FTIR), wide-angle X-ray diffraction (XRD) and thermogravimetric analysis (TGA) revealed that the ionic liquild was loaded in the galleries of organically modified clay. TGA result show the thermal stability of organically modified clay was superior to clay. XRD patterns indicated that the d-spacing of clay layers increased to 2.96 nm from 1.22 nm of clay. XRD patterns of PP/clay nanocomposites show that clay layers were dispersed in PP matrix by nanometer size.

Synthesis and Characterization of Cadmium with Titanium Oxide (Cd-TiO2) Nanocomposite: Testing its Antibacterial Effect

2021 ◽  
Vol 12 (4) ◽  
pp. 2523-2529
Author(s):  
Daniel Sam N ◽  
Anish C I ◽  
Sabeena G ◽  
Rajaduraipandian S ◽  
Manobala ◽  
...  
Keyword(s):  
Sol Gel ◽  
Gram Negative Bacteria ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Gram Negative ◽  
X Ray ◽  
Weight Percentage ◽  
Inhibition Concentration ◽  
Xrd Patterns

Sol gel methods were used for the study of the antimicrobial activity of Cd-TiO2 against gram-negative and positive bacteria. These Cd-TiO2 have been characterized by various optical and techniques. They have been exhibited by X-ray diffraction, scanning electron microscopy, ultraviolet spectroscopy, and infrared spectroscopy. The structures of the various XRD patterns indicate that the product has a structure. The particle size of Cd-TiO2 is 35nm. The SEM images confirm the spherical appearance of the sample. The energy X-ray spectra have been confirmed as well and then C, O, Ti, Cd, Pt element are present in Cd-TiO2. The weight percentage of Cadmium is 5.8%, Ti is 51.03%, C is 5.13% and O is 31.75% in Cd-TiO2. BET image shows that the major pore size distribution of Cd-TiO2 is ranged from 2.24 nm. The Cd-TiO2 that the antibacterial activity when tested against the pathogens only gram-negative bacteria such as Pseudomonas. The zone of minimum inhibition concentration was measured in a range of 20mm in 25μl and 30mm in 100μl.

scholarly journals Preparation and Characterization of Chitosan obtained from Pacific White Shrimp Shells and its in vitro Antifungal Activity

2020 ◽  
Vol 32 (10) ◽  
pp. 2515-2519
Author(s):  
Arnannit Kuyyogsuy
Keyword(s):  
Pacific White Shrimp ◽  
White Shrimp ◽  
X Ray Diffraction ◽  
Vitro Assay ◽  
Shrimp Shells ◽  
Xrd Patterns ◽  
Two Peaks ◽  
In Vitro Antifungal Activity

In this article, a method for the processing of chitosan from Pacific white shrimp shells is developed which involves three steps viz. demineralization, deproteinization, and deacetylation. The samples of chitosan with more than 90% degree of deacetylation (DD%) were obtained by FTIR. This indicated that the current processing method of shrimp shells was beneficial for chitosan production. The morphology of chitosan sample was determined using scanning electron microscopy (SEM). X-ray diffraction (XRD) patterns exhibited two peaks of crystalline character approximately at 10º and 20º (2θ). The effect of 0.1% (w/v) of chitosan on the growth of Penicillium digitatum was tested by an in vitro assay and the results showed an almost complete inhibition (98% ± 0.56).

Preparation and Characterization of Nanocrystalline Gadolinium Oxide Powders and Films

2020 ◽  
Vol 850 ◽  
pp. 267-272 ◽  
Author(s):  
Regina Burve ◽  
Vera Serga ◽  
Aija Krūmiņa ◽  
Raimons Poplausks
Keyword(s):  
Electron Microscopy ◽  
Single Phase ◽  
Gadolinium Oxide ◽  
X Ray Diffraction ◽  
Cubic Crystal ◽  
Glass Substrates ◽  
Oxide Powders ◽  
Transmission Electron ◽  
The Mean

Due to its magnetic, electrical, absorption, and emission properties, nanoscale gadolinium oxide is widely used in various fields. In this research, nanocrystalline Gd2O3 powders and films on glass substrates have been produced by the extraction-pyrolytic method. X-ray diffraction analysis revealed the formation of single phase Gd2O3 with cubic crystal structure and the mean crystallite size from 9 to 25 nm in all produced materials. The morphology of samples has been characterized by scanning electron microscopy and transmission electron microscopy.

Photocatalytic Analysis and Characterization of Zn2SnO4 Nanoparticles Synthesized via Hydrothermal Method with Na2CO3 Mineralizer

2010 ◽  
Vol 97-101 ◽  
pp. 19-22 ◽  
Author(s):  
Yu Shiang Wu ◽  
Wen Ku Chang ◽  
Min Jou
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Process ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
Transmission Electron ◽  
Excellent Photocatalytic Activity ◽  
Face Centered ◽  
Xrd Patterns

Zinc stannate Zn2SnO4 (ZTO) nanoparticles were synthesized via a hydrothermal process utilizing sodium carbonate (Na2CO3) as a weak basic mineralizer. The samples were hydrothermally treated at 150, 200, and 250oC for 48 h. The X-ray diffraction (XRD) patterns show that the highly-crystalline ZTO nanostructure could be formed in a well-dispersed manner for the 250°C sample at a particle size of less than 50 nm. As determined from transmission electron microscopy (TEM) results, ZTO nanoparticles are face-centered cubic single crystals agglomerated together. The Raman spectra results showed that the ZTO nanocrystals have a spinel structure. Furthermore, photocatalytic activity was tested with methylene blue (MB) by UV irradiation. The ZTO synthesized by the 2 M Na2CO3 mineralizer at 250oC demonstrated excellent photocatalytic activity. The ZTO treated three different ways had three distinct UV-Visible absorption curves, which directly influences their corresponding photocatalytic activity.

Mineralogical and physicochemical characterization of selected Portuguese Mesozoic-Cenozoic muddy/clayey raw materials to be potentially used as healing clays

Clay Minerals ◽  
2010 ◽  
Vol 45 (2) ◽  
pp. 229-240 ◽  
Author(s):  
M. Rebelo ◽  
F. Rocha ◽  
E. Ferreira Da Silva
Keyword(s):  
Physicochemical Properties ◽  
Mineral Water ◽  
Raw Materials ◽  
Physicochemical Characterization ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Water Mixture ◽  
X Ray Diffraction ◽  
Geological Formations

AbstractThe use of pelitic geological materials for the treatment of muscle-bone-skin pathologies, by application of a cataplasm made of clay and mineral water mixture, is currently receiving attention and interest from the general public and scientific community. In Portugal there are several natural occurrences of clays/muds which are used for pelotherapy and/or geotherapy. These are carried out either indoors (thalassotherapy and thermal centres) or outdoors, in natural sites generally located near the seaside. The aim of this study is to assess the mineralogical and physicochemical properties of Portuguese raw materials for therapeutic purposes. These materials were collected from different Portuguese Mesozoic-Cenozoic geological formations located in the neighbourhood of thermal centres or at beaches known from their empirical applications. X-ray diffraction (XRD) and scanning electron microscopy (SEM-EDS) were used to assess the mineralogical composition of these clays. Physicochemical properties, such as specific surface area, cation exchange capacity, plasticity/abrasiveness indices and heat diffusiveness were also determined. Having distinct geological ages and genesis, the materials examined are mainly illitic. Less abundant kaolinite and smectite are also present. With respect to their physicochemical properties, all samples have good thermal properties which make them potentially suitable for therapeutic or aesthetic purposes.

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