Examples of Hydrothermal Titration and Real Time X-Ray Diffraction in the Synthesis of Open Frameworks

1996 ◽  
Vol 453 ◽  
Author(s):  
J. B. Parise ◽  
K. Tan ◽  
P. Norby ◽  
Y. Ko ◽  
C. Cahill
Keyword(s):  
Real Time ◽  
Ammonium Hydroxide ◽  
Continuous Exposure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthetic Strategy ◽  
X Ray Scattering ◽  
Different Temperatures ◽  
Imaging Plates ◽  
Insight Into

AbstractHydrothermal titration (HTT) techniques represent a new synthetic strategy for the production of open frameworks. As an example, initial digestion of amorphous GeS2 in the presence of tetraethyl ammonium hydroxide (TEAOH) at 100°C is followed by injection of Ag+ into this mixture to condense the [Ge4S10]4− clusters and form a framework consisting of 8-ring channels bounded by alternating GeS-clusters and Ag+. The rational use of this apparatus depends upon determining the timing of injection. Insight into the changes occurring during reactant digestion is provided by real time synchrotron X-ray powder diffraction. Changes in the the system dimethylamine-Sb-S have been followed in real time at different temperatures. The transformation from mixtures of DMA, Sb and S to the known open phase DMA-SbS-SB8 was followed by observing monochromatic X-ray scattering detected on an imaging plates over a 8 hr period with one continuous exposure.

Back Cover: Dynamic X-Ray Diffraction Computed Tomography Reveals Real-Time Insight into Catalyst Active Phase Evolution (Angew. Chem. Int. Ed. 43/2011)

2011 ◽  
Vol 50 (43) ◽  
pp. 10255-10255 ◽  
Author(s):  
Simon D. M. Jacques ◽  
Marco Di Michiel ◽  
Andrew M. Beale ◽  
Taha Sochi ◽  
Matthew G. O'Brien ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Real Time ◽  
Active Phase ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Back Cover ◽  
Insight Into

scholarly journals Fiber Formation during Melt Blowing

2003 ◽  
Vol os-12 (2) ◽  
pp. 1558925003os-12 ◽  
Author(s):  
Randall R. Bresee ◽  
Wen-Chien Ko
Keyword(s):  
Fiber Diameter ◽  
Fiber Formation ◽  
Experimental Measurements ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Air Velocity ◽  
Melt Blowing ◽  
X Ray ◽  
X Ray Scattering ◽  
Insight Into

Experimental measurements are presented to provide phenomenological insight into the commercial melt blowing process. In particular, we discuss the following experimental measurements obtained at various die-collector locations: fiber diameter, fiber velocity, air velocity, fiber acceleration, fiber entanglement, fiber temperature, birefringence, wide-angle x-ray diffraction and small-angle x-ray scattering. Our discussion focuses on how these measurements provide insight into fiber formation during melt blowing.

Study of Pseudoboehmite Synthesis by Sol-Gel Process

2006 ◽  
Vol 45 ◽  
pp. 260-265 ◽  
Author(s):  
Antônio Hortêncio Munhoz Jr. ◽  
Leila Figueiredo de Miranda ◽  
G.N. Uehara
Keyword(s):  
Sol Gel ◽  
Thermo Gravimetric Analysis ◽  
Ammonium Hydroxide ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sol Gel Process ◽  
Different Temperatures ◽  
Sol Gel Synthesis

A pseudoboehmite was obtained by sol-gel synthesis using aluminum nitrate as precursor. It was used a 2n full factorial design for studying the effect of the temperature of synthesis, the concentration of ammonium hydroxide, and the radiation dose in the product of sol-gel synthesis. The product of the synthesis was analyzed by scanning electron microscopy, x-ray diffraction of the product (after firing the pseudoboehmite at different temperatures), and it was also analyzed the temperature of endothermic and exothermic transformations using the thermo gravimetric analysis (TG) and differential scanning calorimetry (DSC). The X-ray diffraction data show that α-alumina was obtained at 1100o C.

Dynamic X-Ray Diffraction Computed Tomography Reveals Real-Time Insight into Catalyst Active Phase Evolution

2011 ◽  
Vol 123 (43) ◽  
pp. 10330-10334 ◽  
Author(s):  
Simon D. M. Jacques ◽  
Marco Di Michiel ◽  
Andrew M. Beale ◽  
Taha Sochi ◽  
Matthew G. O'Brien ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Real Time ◽  
Active Phase ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Insight Into

Rücktitelbild: Dynamic X-Ray Diffraction Computed Tomography Reveals Real-Time Insight into Catalyst Active Phase Evolution (Angew. Chem. 43/2011)

2011 ◽  
Vol 123 (43) ◽  
pp. 10437-10437 ◽  
Author(s):  
Simon D. M. Jacques ◽  
Marco Di Michiel ◽  
Andrew M. Beale ◽  
Taha Sochi ◽  
Matthew G. O'Brien ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Real Time ◽  
Active Phase ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Insight Into

scholarly journals Fenton-Type Bimetallic Catalysts for Degradation of Dyes in Aqueous Solutions

Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 32
Author(s):  
Bebiana L. C. Santos ◽  
Pier Parpot ◽  
Olívia S. G. P. Soares ◽  
Manuel F. R. Pereira ◽  
Elisabetta Rombi ◽  
...  
Keyword(s):  
Bimetallic Catalysts ◽  
Environmental Remediation ◽  
X Ray Diffraction ◽  
Nay Zeolite ◽  
Exchange Method ◽  
Y Zeolites ◽  
X Ray ◽  
Degradation Of Dyes ◽  
Different Temperatures ◽  
Insight Into

Dye compounds are becoming a problematic class of pollutants for the environment, so it is important to develop stable catalysts for their elimination. First, several studies were performed with different Y zeolites (NaY, (NH4)Y and USY) in order to select the best support for the preparation of the bimetallic catalysts. In particular, NaY zeolite was used as the support for Fe, Cu and Mn metals to prepare mono and bimetallic Fenton-type catalysts by the ion exchange method. The catalysts were characterized by several techniques, such as chemical analysis, nitrogen physisorption, X-ray diffraction (XRD), scanning electron microscopy (SEM) and cyclic voltammetry studies. Characterization results revealed that the metals were successfully ion-exchanged within the NaY zeolite. The prepared catalysts were tested for the aqueous-phase degradation of dye compounds (Procion yellow (PY) and Tartrazine (Tar)) at atmospheric pressure and different temperatures, using H2O2 as the oxidant. All the investigated samples were found to be active in degrading the dyes through the Fenton-type process; however, the oxidation rate was found to be higher in the presence of the bimetallic catalysts. CuFe-NaY displays the best mineralization rate for PY oxidation while MnFe-NaY shows the highest activity for Tar degradation. This work may provide further insight into the design of Fenton-type bimetallic catalysts with improved catalytic properties for environmental remediation.

Exotic X-ray back-diffraction: a path toward a soft inelastic X-ray scattering spectrometer

2014 ◽  
Vol 47 (5) ◽  
pp. 1658-1665 ◽  
Author(s):  
Marcelo Goncalves Hönnicke ◽  
Raymond Conley ◽  
Cesar Cusatis ◽  
Edson Massayuki Kakuno ◽  
Juan Zhou ◽  
...  
Keyword(s):  
Dynamical Theory ◽  
Extreme Condition ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Magnetic Imaging ◽  
X Ray Scattering ◽  
Low Energies ◽  
Different Temperatures ◽  
Ray Scattering

In this work, soft X-ray back-diffraction (XBD; X-ray diffraction at angles near and exactly equal to 90°) is explored. The experiment was conducted at the SXS beamline at Laboratorio Nacional de Luz Sincrotron, Brazil, at ∼3.2 keV. A high-resolution Si(220) multi-bounce back-diffraction monochromator was designed and constructed for this experiment. An ultra-thin Si(220) crystal (5 µm thick) was used as the sample. This ultra-thin crystal was characterized by profilometry, rocking-curve measurements and X-ray topography prior to the XBD measurements. It is shown that the measured forward-diffracted beam (o-beam) profiles, taken at different temperatures, are in close agreement with profiles predicted by the extended dynamical theory of X-ray diffraction, with the absence of multiple-beam diffraction (MBD). This is an important result for future studies on the basic properties of back-diffracted X-ray beams at energies slightly above the exact XBD condition (extreme condition where XBD is almost extinguished). Also, the results presented here indicate that stressed crystals behave like ideal strain-free crystals when used for low-energy XBD. This is mainly due to the large widths of XBD profiles, which lead to a low strain sensitivity in the detection of defects. This result opens up new possibilities for mounting spherical analyzers without degrading the energy resolution, at least for low energies. This is a path that may be used to construct a soft inelastic X-ray scattering spectrometer where different applications such as element-specific magnetic imaging tools could be explored.

Dynamic X-Ray Diffraction Computed Tomography Reveals Real-Time Insight into Catalyst Active Phase Evolution

2011 ◽  
Vol 50 (43) ◽  
pp. 10148-10152 ◽  
Author(s):  
Simon D. M. Jacques ◽  
Marco Di Michiel ◽  
Andrew M. Beale ◽  
Taha Sochi ◽  
Matthew G. O'Brien ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Real Time ◽  
Active Phase ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Insight Into

New Structure of CTAB Templated Silica Films as revealed by GISAXS coupled to HRTEM

2000 ◽  
Vol 628 ◽  
Author(s):  
Sophie Besson ◽  
Catherine Jacquiod ◽  
Thierry Gacoin ◽  
André Naudon ◽  
Christian Ricolleau ◽  
...  
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Grazing Incidence ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Hexagonal Arrangement ◽  
Spherical Micelles

ABSTRACTA microstructural study on surfactant templated silica films is performed by coupling traditional X-Ray Diffraction (XRD) and Transmission Electronic Microscopy (TEM) to Grazing Incidence Small Angle X-Ray Scattering (GISAXS). By this method it is shown that spin-coating of silicate solutions with cationic surfactant cetyltrimethylammonium bromide (CTAB) as a templating agent provides 3D hexagonal structure (space group P63/mmc) that is no longer compatible with the often described hexagonal arrangement of tubular micelles but rather with an hexagonal arrangement of spherical micelles. The extent of the hexagonal ordering and the texture can be optimized in films by varying the composition of the solution.

scholarly journals X-ray and Neutron Study on the Structure of Hydrous SiO2 Glass up to 10 GPa

Minerals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 84 ◽  
Author(s):  
Satoru Urakawa ◽  
Toru Inoue ◽  
Takanori Hattori ◽  
Asami Sano-Furukawa ◽  
Shinji Kohara ◽  
...  
Keyword(s):  
Oxide Glasses ◽  
Void Space ◽  
X Ray Diffraction ◽  
Amorphous Sio2 ◽  
Sio2 Glass ◽  
X Ray ◽  
X Ray Scattering ◽  
Medium Range ◽  
Two Phases ◽  
A Minor

The structure of hydrous amorphous SiO2 is fundamental in order to investigate the effects of water on the physicochemical properties of oxide glasses and magma. The hydrous SiO2 glass with 13 wt.% D2O was synthesized under high-pressure and high-temperature conditions and its structure was investigated by small angle X-ray scattering, X-ray diffraction, and neutron diffraction experiments at pressures of up to 10 GPa and room temperature. This hydrous glass is separated into two phases: a major phase rich in SiO2 and a minor phase rich in D2O molecules distributed as small domains with dimensions of less than 100 Å. Medium-range order of the hydrous glass shrinks compared to the anhydrous SiO2 glass by disruption of SiO4 linkage due to the formation of Si–OD deuterioxyl, while the response of its structure to pressure is almost the same as that of the anhydrous SiO2 glass. Most of D2O molecules are in the small domains and hardly penetrate into the void space in the ring consisting of SiO4 tetrahedra.

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