Humidity Controlled Diffractometry and its Applications

1992 ◽  
Vol 36 ◽  
pp. 439-449 ◽  
Author(s):  
Radko A. Kühnel ◽  
Sjerry J. van der Gaast
Keyword(s):  
Structural Changes ◽  
Basic Research ◽  
Xrd Analysis ◽  
Reaction Rates ◽  
Hydrous Minerals ◽  
X Ray ◽  
Special Attachment ◽  
Potential Applications ◽  
Total Structure ◽  
Structure Collapse

AbstractHumidity sensitive mineral phases change their structure when humidity varies resulting in X-ray pattern changes in intensity, position, and shape of lines. These structural changes in hydrous minerals are induced by dehydration and rehydration, which can lead to phase transformations or to steady depletion which may result in a total structure collapse. By means of X-ray diffraction with a special attachment, such reactions can be followed. The controlled relative humidity is provided in situ, in a closed cell, by a flow of moistened helium gas which is flushed through the cell during the XRD analysis. Humidity diffractometry allows studies of reaction rates of dehydration-rehydration reactions and their reversibilities, as well as effects of additives and impurities on these reactions. Potential applications in basic research and in industry are demonstrated using montmorilionite, ettringites, sodium carbonates and calcium sulfates.

scholarly journals Effect of Transitional Metals (Mn and Ni) Substitution in LiCoPO4 Olivines

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 601
Author(s):  
Oriele Palumbo ◽  
Jessica Manzi ◽  
Daniele Meggiolaro ◽  
Francesco M. Vitucci ◽  
Francesco Trequattrini ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Structural Changes ◽  
Transition Metal Ions ◽  
Xrd Analysis ◽  
Partial Substitution ◽  
Structural Alterations ◽  
X Ray ◽  
Transitional Metals ◽  
The Impact

Transition metal substitution is a key strategy to optimize the functional properties of advanced crystalline materials used as positive electrodes in secondary lithium batteries (LIBs). Here we investigate the structural alterations in the olivine lattice of Mn and Ni substituted LiCoPO4 phase and the impact on performance in LIBs. X-ray diffraction (XRD) and extended X-ray absorption experiments have been carried out in order to highlight the structural alterations induced by partial substitution of cobalt by manganese and nickel. XRD analysis suggests that substitution induces an expansion of the lattices and an increase of the antisite disorder between lithium and transition metal ions in the structure. XAS data highlight negligible electronic disorder but a relevant modulation in the local coordination around the different metal ions. Moreover, galvanostatic tests showed poor reversibility of the redox reaction compared to the pure LCP sample, and this failure is discussed in detail in view of the observed remarkable structural changes.

THERMALLY-DRIVEN STRUCTURAL CHANGES OF SPUTTERED COPPER ALUMINUM OXIDE FILMS (Cu–Al2O3) GROWN BY LAYER STACKING METHOD

2017 ◽  
Vol 24 (Supp01) ◽  
pp. 1850002
Author(s):  
WEI QIANG LIM ◽  
SHANMUGAN SUBRAMANI ◽  
MUTHARASU DEVARAJAN
Keyword(s):  
Crystallite Size ◽  
Structural Properties ◽  
Structural Changes ◽  
Annealing Temperature ◽  
Compressive Strain ◽  
Rf Magnetron Sputtering ◽  
Xrd Analysis ◽  
X Ray ◽  
Layer Stacking ◽  
Deposited Films

Copper aluminium oxide (Cu–Al2O3) films were synthesized on Si(111) substrates through RF magnetron sputtering by using the layer stacking technique. Cu and Al2O3 targets were used to deposit Cu and Al2O3 thin films under Ar atmosphere, respectively and the deposited films were then annealed under N2 environment at 350[Formula: see text]C, 450[Formula: see text]C and 550[Formula: see text]C for 6[Formula: see text]h. The structural properties of the films were investigated by using X-ray diffraction (XRD) while the surface morphology and topography of the deposited films were examined through Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray (EDX) and Atomic Force Microscopy (AFM). XRD analysis revealed the existence of multiple phases of CuO, Al2O3 and CuAl2O4 in the deposited films on Si(111) substrates. As a result of the annealing effect, the peak intensities of CuO, Al2O3 and CuAl2O4 were found to be increased along with the shifting of peak positions. Williamson–Hall (WH) analysis was also implemented to analyze the structural properties such as crystallite size, stress, strain, and energy density. Based on the three models used in WH analysis, the changes in the crystallite size and strain of the films were indicated to be anomalous with the changes in the annealing temperature. Moreover, the strain of films was also showed to be changed from compressive strain into tensile strain. The FESEM results also indicated the formation of various surface morphologies under various annealing temperatures whereas EDX analysis showed an increased atomic percentage of Cu, Al, and O due to the effect of increase in annealing temperature. The AFM analysis showed that the surface roughness of the deposited films increased with the increase in the annealing temperature.

Highly Efficient and Recyclable Diatomite-Supported Pd Nanoparticles for the Suzuki-Miyaura Coupling Reaction

2010 ◽  
Vol 113-116 ◽  
pp. 1824-1827 ◽  
Author(s):  
Cheng Jun Hao ◽  
Xiao Jun Zhao
Keyword(s):  
Palladium Nanoparticles ◽  
Coupling Reaction ◽  
Pd Nanoparticles ◽  
Xrd Analysis ◽  
Reaction Rates ◽  
X Ray ◽  
Highly Active ◽  
Transmission Electron ◽  
High Yields ◽  
Supported Pd

The Suzuki-Miyaura coupling reaction catalyzed by Pd nanoparticles immobilized on widespread natural diatomite has been reported in this report. The reaction showed enhanced reaction rates, high yields, and the conditions were environmentally friendly. The highly active heterogeneous catalyst of palladium nanoparticles allow the reaction to be performed at low catalyst levels, and could be reused 5 times with little loss of activity. Transmission electron microscopy (TEM) and X-ray powder diffraction (XRD) analysis characteried the diatomite-supported Pd(0) nanoparticles as catalyst for the reaction.

scholarly journals Effect of Time on a Hierarchical Corn Skeleton-Like Composite of CoO@ZnO as Capacitive Electrode Material for High Specific Performance Supercapacitors

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3285 ◽  
Author(s):  
Yedluri Kumar ◽  
Hee-Je Kim
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Xrd Analysis ◽  
Cycling Performance ◽  
Energy Storage Devices ◽  
Tem Analysis ◽  
X Ray ◽  
Potential Applications ◽  
Oxygen Groups

CoO–ZnO-based composites have attracted considerable attention for the development of energy storage devices because of their multifunctional characterization and ease of integration with existing components. This paper reports the synthesis of CoO@ZnO (CZ) nanostructures on Ni foam by the chemical bath deposition (CBD) method for facile and eco-friendly supercapacitor applications. The formation of a CoO@ZnO electrode functioned with cobalt, zinc, nickel and oxygen groups was confirmed by X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), low and high-resolution scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analysis. The as-synthesized hierarchical nanocorn skeleton-like structure of a CoO@ZnO-3h (CZ3h) electrode delivered a higher specific capacitance (Cs) of 1136 F/g at 3 A/g with outstanding cycling performance, showing 98.3% capacitance retention over 3000 cycles in an aqueous 2 M KOH electrolyte solution. This retention was significantly better than that of other prepared electrodes, such as CoO, ZnO, CoO@ZnO-1h (CZ1h), and CoO@ZnO-7h (CZ7h) (274 F/g, 383 F/g, 240 F/g and 537 F/g). This outstanding performance was attributed to the excellent surface morphology of CZ3h, which is responsible for the rapid electron/ion transfer between the electrolyte and the electrode surface area. The enhanced features of the CZ3h electrode highlight potential applications in high performance supercapacitors, solar cells, photocatalysis, and electrocatalysis.

scholarly journals Nanocrystallization of Vanadium Borophosphate Glass for Improving the Electrical and Catalytic Properties

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Su-Yeon Choi ◽  
Bong-Ki Ryu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Changes ◽  
Catalytic Effect ◽  
Xrd Analysis ◽  
Annealed Sample ◽  
Molecular Volume ◽  
X Ray ◽  
Valence States ◽  
Heat Treated ◽  
Structural And Electrical Properties

75V2O5-10P2O5-15B2O3ternary-system glasses were prepared and nanocrystallized to examine the catalytic effect and the variations in their structural and electrical properties. These glasses were annealed in a graphite mold above the glass transition temperature for 2 h and heat-treated at the crystallization temperature for 1, 3, and 5 h. Fourier transform infrared spectroscopy (FTIR) was used to analyze the structural changes in the B-O bonds after nanocrystallization, while X-ray photoelectron spectroscopy (XPS) analysis showed a decrease in V5+and an increase in V4+. X-ray diffraction (XRD) analysis of the structure array (BO3+ V2O5  ↔BO4+ 2VO2) verified these inferred changes. Structural changes induced by the heat treatment were confirmed by analyzing the molecular volume determined from the sample density. Conductivity and catalytic effects were discussed based on the migration of vanadate ions with different valence states due to the increase in VO2nanocrystallinity at 275°C. Both conductance and the catalytic effect were higher after nanocrystallization at 275°C for 1 h compared to the annealed sample. Furthermore, compared to the sample heat-treated for 1 h, the conductance and catalytic effect were increased and decreased, respectively, for samples nanocrystallized at 275°C for 3 and 5 h.

Article

1998 ◽  
Vol 76 (12) ◽  
pp. 1853-1859
Author(s):  
Herbert Höpfl ◽  
Norberto Farfán
Keyword(s):  
Structural Changes ◽  
Heterocyclic Ring ◽  
Boron Chelates ◽  
X Ray ◽  
X Ray Crystallography ◽  
Chelate Formation ◽  
Structural Differences ◽  
Boron Complex ◽  
Potential Applications ◽  
Diphenylboron Chelate

Boron chelates obtained from salicylaldehyde and 2prime-hydroxyacetophenone azines are colored compounds with potential applications in analytical chemistry. Up to now these complexes have not been studied by X-ray crystallography, although two structures with a six- or a seven-membered chelate ring are possible. This contribution presents the X-ray analysis of 2prime-hydroxyacetophenone azine and its corresponding new mono(diphenylboron) chelate with a six-membered boron heterocyclic ring. With these data structural changes of the ligand on chelate formation and structural differences in comparison to salicylaldehyde azomethine boron chelates are discussed.Key words: boron complex, borinate, azine, azomethine.

scholarly journals Synthesis of Tin(II) Oxide (SnO) Nanoparticle by Hydrothermal Method

2019 ◽  
Vol 4 (3) ◽  
pp. 145
Author(s):  
Saddam Husein ◽  
Endang Tri Wahyuni ◽  
Mudasir Mudasir
Keyword(s):  
Hydrothermal Method ◽  
Low Temperatures ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Simple Hydrothermal Method ◽  
X Ray ◽  
Chloride Dihydrate ◽  
Synthesis Parameters ◽  
Tetragonal Crystal ◽  
Potential Applications

<p>This study aims to prepare nanomaterial tin(II) oxide (SnO) by using a simple hydrothermal method at low temperatures. The precursors used were tin(II) chloride dihydrate and sodium hydroxide pellets. Solid tin(II) chloride dihydrate and natrium hydroxide pellets are firstly dissolved in ethanol solvents separately and stirred for 3 h for each solution at a constant temperature 26<sup>o</sup>C. Characterization in this study were carried out by using X-ray diffraction (XRD) and Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX). The results of the XRD analysis shows that the sample of SnO nanoparticle is in accordance with the standard JCPDS SnO structure. SnO nanoparticle has tetragonal crystal structures and PSC: tp4 groups. It can be concluded that the tetragonal SnO nanostructure can be produced by a simple hydrothermal method at low temperatures by optimizing several synthesis parameters. The structure of SnO nanostructure has several potential applications i.e the absorption of heavy metals, optics, and as a catalyst for dye photodegradation.</p>

scholarly journals Structural Changes of Bacillus subtilis Biomass on Biosorption of Iron (II) from Aqueous Solutions: Isotherm and Kinetic Studies

2019 ◽  
Vol 68 (4) ◽  
pp. 549-558 ◽  
Author(s):  
SRI LAKSHMI RAMYA KRISHNA KANAMARLAPUDI ◽  
SUDHAMANI MUDDADA
Keyword(s):  
Bacillus Subtilis ◽  
Aqueous Solutions ◽  
Structural Changes ◽  
Low Cost ◽  
Bacterial Biomass ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Xrd Analysis ◽  
Experimental Conditions ◽  
X Ray

Various microbial biomasses have been employed as biosorbents. Bacterial biomass has added advantages because of easy in production at a low cost. The study investigated the biosorption of iron from aqueous solutions by Bacillus subtilis. An optimum biosorption capacity of 7.25 mg of the metal per gram of the biosorbent was obtained by the Inductive Coupled Plasma Optical Emission Spectroscopy (ICP-OES) under the experimental conditions of initial metal concentration of 100 mg/l, pH 4.5, and biomass dose of 1 g/l at 30°C for 24 hrs. The data showed the best fit with the Freundlich isotherm model while following pseudo-first-order kinetics. Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) analysis confirmed iron biosorption as precipitates on the bacterial surface, and as a peak in the EDX spectrum. The functional hydroxyl, carboxyl, and amino groups that are involved in biosorption were revealed by the Fourier Transform Infrared spectroscopy (FTIR). The amorphous nature of the biosorbent for biosorption was indicated by the X-ray Diffraction (XRD) analysis. The biomass of B. subtilis exhibited a point zero charge (pHpzc) at 2.0.

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

scholarly journals Functional Attributes of Myco-Synthesized Silver Nanoparticles from Endophytic Fungi: A New Implication in Biomedical Applications

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 473
Author(s):  
Prabu Kumar Seetharaman ◽  
Rajkuberan Chandrasekaran ◽  
Rajiv Periakaruppan ◽  
Sathishkumar Gnanasekar ◽  
Sivaramakrishnan Sivaperumal ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Culture Filtrate ◽  
Morphological Changes ◽  
Xrd Analysis ◽  
Penicillium Oxalicum ◽  
Breast Cancer Cell Lines ◽  
Face Centered Cubic ◽  
Tem Analysis ◽  
X Ray ◽  
Average Size

To develop a benign nanomaterial from biogenic sources, we have attempted to formulate and fabricate silver nanoparticles synthesized from the culture filtrate of an endophytic fungus Penicillium oxalicum strain LA-1 (PoAgNPs). The synthesized PoAgNPs were exclusively characterized through UV–vis absorption spectroscopy, Fourier Transform Infra-Red spectroscopy (FT-IR), X-ray powder diffraction (XRD), and Transmission Electron Microscopy (TEM) with energy dispersive X-ray spectroscopy (EDX). The synthesized nanoparticles showed strong absorbance around 430 nm with surface plasmon resonance (SPR) and exhibited a face-centered cubic crystalline nature in XRD analysis. Proteins presented in the culture filtrate acted as reducing, capping, and stabilization agents to form PoAgNPs. TEM analysis revealed the generation of polydispersed spherical PoAgNPs with an average size of 52.26 nm. The PoAgNPs showed excellent antibacterial activity against bacterial pathogens. The PoAgNPs induced a dose-dependent cytotoxic activity against human adenocarcinoma breast cancer cell lines (MDA-MB-231), and apoptotic morphological changes were observed by dual staining. Additionally, PoAgNPs demonstrated better larvicidal activity against the larvae of Culex quinquefasciatus. Moreover, the hemolytic test indicated that the as-synthesized PoAgNPs are a safe and biocompatible nanomaterial with versatile bio-applications.

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