X-ray Diffraction

(2018). Synthesis of galaxite, Mn0.9Co0.1Al2O4, and its applications a novel nanocatalyst for electrochemical hydrogen evolution reaction. Physica B: Condensed Matter, 538, 172-178. https://doi. Abstract A new compound Mn 0.9 Co 0.1 Al 2 O 4 nanowires were synthesized by thermal method. The resulting powder samples were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). We found that a set of phase transformation occurred during the process. Eventually, five phases including three spinal phases, the corundum (á-Al 2 O 3) and MnO were formed at 1100 °C.As dominant morphology, the cubic galaxite nanowires were identified by X-ray analysis. Moreover, X-ray analysis showed that Mn 3 O 4 and Co 3 O 4 nanoparticles were formed in tetragonal and cubic symmetry respectively. The SEM image revealed that a dominate morphology of product has cubic nanowires shape with an average diameter in range 38-43 nm. Furthermore, we observed that influence of temperature was very important in the nanowire formation process. Electrochemical hydrogen evolution reaction (HER) of synthetic composite was evaluated and the over potential of HER was calculated about 110 mV with low Tafel slope equal to 42 mV dec−1, which was comparable with amounts reported transition metal dichalcogenides with satisfying durability.

Since 2006, there has been a resurgent interest in the pharmacology and therapeutics of psychedelic drugs. Psilocybin, the 4-phosphoryl ester of N,N-dimethyltryptamine (DMT), has been studied most often, but DMT itself is also appealing because of its brief but profound psychological effects and its presence as an endogenous substance in mammalian brain. Although there have been a few studies of ayahuasca, a DMT-containing water infusion, only one human study with pure DMT has been reported since the early 2000s. Newly planned clinical trials to assess the safety and efficacy of DMT in humans with major depressive disorder require high-purity water-soluble DMT for intravenous administration. Accordingly, we synthesized and characterized DMT hemifumarate for these upcoming studies. The synthetic approach of Speeter and Anthony was slightly modified to gain some efficiency in time. In particular, this is the first known report to use aluminum hydride, generated in situ from lithium aluminum hydride, to reduce the intermediate 2-(1H-indol-3-yl)-N,N-dimethyl-2-oxoacetamide to DMT. A quench protocol was developed to produce a good yield of exceptionally pure free base DMT upon workup, which was then converted to the hemifumarate salt. Analysis of the final product included differential scanning calorimetry, thermogravimetric analysis, gas chromatography-mass spectrometry, 1H and 13C nuclear magnetic resonance spectroscopy, high-performance liquid chromatography, residual solvent analysis by gas chromatography headspace sampling, X-ray powder diffraction analysis, and residual lithium analysis by inductively coupled plasma-mass spectrometry. The DMT hemifumarate was minimally 99.9% pure, with no significant impurities or residual solvents, thus meeting regulatory standards for administration to humans.

Οι πρώτες αναλύσεις με την μέθοδο των «λεπτών τομών» (“thin sections”), και της portable X-ray fluorescence analysis (pXRF) στα οκτώ δείγματα που περιελήφθησαν στο πρόγραμμα του 2017-2018, και καλύπτουν ένα μεγάλο φάσμα μεταξύ λεπτοφυών, ημιλεπτοφυών και χονδροειδών κεραμικών, δείχνουν στην κατεύθυνση ενός πλήθους διαφορετικών τιμών, εντός του πλαισίου μιας ευρύτερης κοινής προέλευσης, που σχετίζεται με το γεωλογικό προφίλ της περιοχής της έρευνας.
Δεν είναι δυνατόν να αποδώσουμε τα δείγματά μας σε ένα κοινό
κεραμικό εργαστήριο, αλλά ούτε και σε μία κοινή πηγή πηλού. Εντούτοις, δεν μπορούμε επίσης να αποκλείσουμε την υπόθεση ότι τα δείγματά μας ανήκουν σε προϊόντα μιας κοινής κεραμικής βιοτεχνίας που υιοθέτησε ένα «μοντέλλο με πολλούς κλάδους», στο οποίο περιελήφθησαν διαφορετικοί κεραμείς, οι οποίοι θα εργάσθηκαν σε γειτονία, παράγοντας διαφορετικούς τύπους λεπτοφυούς και χονδροειδούς κεραμικής.
Ηφαιστειογενής είναι η προέλευση των πηγών πηλού για όλα, σχεδόν,
τα δείγματά μας. Είναι σημαντικό να παρατηρήσουμε ότι ο παραπάνω
κανόνας ισχύει και για τα πλέον λεπτά κεραμικά από τα οποία
ελήφθησαν δείγματα. Η θεωρία, λοιπόν, της χρήσης της τοπικής
λεπτοφυούς κεραμικής ως συνοδού φορτίου των μηλιακών ορυκτών και του μηλιακού οίνου, που προορίζονταν για τις αγορές της Δύσης, μπορεί να θεωρηθεί ως ευρισκόμενη εν ισχύ, για μελλοντική αξιολόγηση.
Το ηφαιστειακό έγκλεισμα του δείγματος #1 και τα χαλαζιακά
εγκλείσματα των δειγμάτων #4, #52 , #53 , #6, η παρουσία αλουνίτη, θείου και μαγγανίου στα δείγματα #2, #3, αλλά και η παρουσία αλουμινίου, καλίου και θείου στο δείγμα #8, αποτελούν ενθαρρυντικές ενδείξεις για την μηλιακή προέλευση του υλικού μας.
Άς σημειωθεί ότι χαλαζίες και άστριοι χαρακτηρίζουν την σύσταση των χονδροειδών αγγείων για καθημερινή χρήση από τις ανασκαφές μας.
Επιπλέον, τα εγκλείσματα ασβεστίου του δείγματος #6 και το μαγγάνιο του δείγματος #2 δεν είναι χωρίς παράλληλα στα πορίσματα των παλαιότερων αναλύσεων περιεχομένου: Αφού, τόσο στην περίπτωση των δειγμάτων αγγείων, όσο και στην περίπτωση των δειγμάτων περιεχομένου, έχουμε να κάνουμε με πηλούς, η συνολική εικόνα δεν είναι παράταιρη.
Θα πρέπει να περιμένουμε για την επόμενη φάση των αναλύσεων / πορισμάτων, ώστε να επανασχεδιάσουμε την μελλοντική μας έρευνα σχετικώς με την παραγωγή των κεραμικών εργαστηρίων στην Μήλο των Ρωμαϊκών χρόνων.
The first thin section / portable X-ray fluorescence analysis (pXRF)
analyses of fine wares in the 2017-2018 project points towards a
plethora of minor differences amongst fine, semi-fine and coarse
material analysed. We definitely cannot attribute our speciments
to a common workshop, nor to a common clay source. Yet, neither
can we exclude the hypothesis that these are actually products of
a pottery industry that adopted a multi-branch model, that
included different potters working in vicinity, producing different
types of fine and coarse ceramic products.
A volcanic origin is possible for almost all of the newly analysed
speciments. What is really promising, is that, the above rule, can
be applied even to the the “finest” of our fine ware speciments. So,
our theory concerning the use of that type of pottery as spacefillers for ship cargos trading melian wine and alumen is still valid
and can stay on the table for future evaluation.
The volcanic inclusion of #1 and the quartz inclusions of #4, #52 ,
#53 , #6, the presence of alunite, sulfur and manganese in #2, #3, as
well as the aluminium, potassium and sulphur of #8, are certainly
encouraging indication of a Melian origin for the samples under
evaluation. Note that quartz and asrtii were typical finds amongst
melian kitchenware samples. More than that, calcite inclusions of
#6 and the manganese content of #2 clay, remind us of the
previous pot sediment (contents) results. Since in both cases
(containers and contents) we are dealing with clays, this is not
something out of place, on the contrary it is rather encouraging.
We will have to wait until the final analyses show us more, and
then we could probably re-schedule our future work on melian
fine and semi-fine roman pottery production.

Two new 1-benzhydrylpiperazinium carboxylates
with tartrate and maleate, (C17H21N2)(C4H5O6) and
(C17H22N2)(C4H3O4)2, have been synthesized and characterized.
Crystal structure determinations show that the
compounds crystallize in the P21 and the P21/c space
groups of the monoclinic system, respectively. Only in the
maleate the organic group is protonated on both nitrogen
atoms of piperazine ring. The infrared spectra of these
compounds reported from 400 to 4000 cm-1 confirmed the
presence of the principal bands assigned to the internal
modes of cations and anions of both compounds. The
optical band gaps were calculated and found to be 3.46 and
4.14 eV for tartrate and maleate, respectively. Different
molecular motions were determinate via dielectric relaxation
spectroscopy. Measurements of AC conductivity as a
function of frequency at different temperatures indicated
the hopping conduction mechanism. The number of 13C CP-MAS NMR lines is in good agreement with the crystallographic
data.

AMPA receptors comprise an important class of ionotropic glutamate receptors activated by glutamate in the central nervous system. These receptors have been shown to be involved in brain diseases, e.g. Alzheimer’s disease and epilepsy. To understand the functional role of AMPA receptors at the molecular level and their potential as targets for drugs, development of tool compounds is essential. We have previously reported the synthesis of six bicyclic pyrimidinedione-based analogues of willardiine with differences limited to the pyrimidinedione-fused five-membered rings. Despite minor molecular differences, we observed >500-fold difference in binding affinity of the compounds at full-length GluA2. Here, we report binding affinities and the binding mode of these compounds at the ligand-binding domain of GluA2 using X-ray crystallography. The structures revealed similar binding modes, but with distinct differences in the interaction between GluA2 and the compounds. The methylene (2) and sulfur (3) containing compounds showed the greatest binding affinities. Changing the dihydrothiophene (3) into pyrrolidine (4), N-methyl pyrrolidine (5) or dihydrofuran (6) induced flexibility in the position of a binding-site water molecule and changes in the hydrogen-bonding network between compound, water and GluA2. This might be essential for explaining the reduced binding affinity of these compounds. The weakest binding affinity was observed when the aliphatic oxygen containing dihydrofuran (6) was changed into an aromatic furan system (7). Molecular docking studies revealed two possible orientations of 7, whereas only one binding mode was observed for the other analogues. This could likely contribute to the weakest binding affinity of 7 at GluA2.

In the present work sand-blasting-induced structural, thermal, and mechanical effects were studied in Zr58.3Cu18.8Al14.6Ni8.3 bulk metallic glass. It was observed that sand blasting favors disordering of the atomic configuration, formation of free volume and evolution of multiple intersecting shear bands. As a result, considerable compressive plasticity was achieved in sand-blasted samples. It was also observed that in order to superimpose the effect of pre-straining and extra free volume for improving compressive plasticity, there exists a limit to both parameters.

The equiatomic multicomponent AlCoCrCuFeNi hexanery high entropy alloy (HEA) was synthesized by mechanical alloying. The effect of the addition of W and Zr was studied by making equiatomic AlCoCrCuFeNiW septenary and AlCoCrCuFeNiWZr octonary high entropy alloys. The effect of alloying addition with milling time was studied using XRD, DSC/TGA, SEM, TEM and Mossbauer spectroscopy. Supersaturated solid solution structure was achieved after 60 h milling for hexanery alloy and after 40 h milling for both septenary and octonary high entropy alloys. The variation of Mossbauer parameters for AlCoCrCuFeNi system with the addition of W and Zr makes its magnetic environment more complex which is indicated by the conversion of magnetic AlCoCrCuFeNi HEA (60 h milling) to partially paramagnetic AlCoCrCuFeNiW (40 h milling) to completely paramagnetic AlCoCrCuFeNiWZr high entropy alloy.

Fatigue crack growth in the Heat Affected Zone (HAZ) of a welded CrNiMoV steel has been investigated, in situ, using Digital Image Correlation (DIC) and Energy Dispersive X-Ray Diffraction (EDXD). Compact tension specimens of welded joint were loaded under tension-tension cyclic loading. The crack tip position and the evolution of the near-tip strains normal to the crack plane were tracked at selected positions for a growing fatigue crack both on the specimen surface using {DIC} and in the bulk of the specimen using {EDXD} of synchrotron X-rays. The uncertainty and quality of the {DIC} measurements were examined with regard to some of the key data processing parameters, including subset size and the size of measurement window; whilst the measurement errors in the {EDXD} measurements were also estimated. A “characteristic” strain was estimated, in the bulk of the specimen and on the specimen surface, from the average strains captured at selected positions when the propagating fatigue crack tip reached these positions.

Synchrotron Energy Dispersive X-ray Diffraction (EDXD) and Digital Image Correlation (DIC) have been applied to map simultaneously the 2D elastic strain and displacement fields of a propagating fatigue crack in the HAZ of a welded Cr2Ni4MoV bainitic steel. The position of the crack tip was tracked via a phase congruency analysis of the displacement field, and also by detection of its cyclic plastic zone. Both types of full field data provided independent inputs to finite element/J-integral analyses that directly quantified the elastic cyclic stress intensity factor range applied to the crack. No knowledge was required of the specimen geometry, crack length or applied loads. The agreement between the two analyses in this controlled study shows that strain mapping by synchrotron EDXD can provide a reliable method to study the crack fields in more complex problems, such as interactions between crack closure, residual stresses and applied loading.

n-situ fracture tests were carried out on the I12 beamline at the Diamond Light Source. Four Al-Ti metal-matrix composites (MMCs), with two crack lengths, were studied to assess for the impact of in-plane constraint. Synchrotron X-ray computed tomography and synchrotron X-ray diffraction were used to measure total strain and elastic strain respectively. In this work, the measured elastic strains in the samples are detailed as a function of applied load and compared against those predicted from a 3D elastic-plastic finite element model. The modelled strains increased asymptotically towards the tip of the electro discharge machined notch. The experimental results do not highlight the same response, which is due to a combination of blunting and low experimental spatial resolution. Far field experimental and measured strain fields converged, notably in the test piece containing a long notch (a/W = 0.5) and higher levels of constraint.

Sr1.50Ca1.50Fe2.25Mo0.75O9– and Sr1.92Ca1.08Fe2.04W0.96O9– double perovskites are synthesized in
the polycrystalline form by a solid-state reaction route in air and studied at room temperature
using the of PXRD, Raman and Mössbauer spectroscopy techniques. The Rietveld refinement
analysis reveals that both compounds adopt a tetragonal system with the space group I4/m and
lattice parameters a = b = 5.5176(1) Å and c = 7.8065(2) Å for Sr1.50Ca1.50Fe2.25Mo0.75O9– and
a = b = 5.5453(1) Å and c = 7.8388(1) Å for Sr1.92Ca1.08Fe2.04W0.96O9–. Raman spectra are consistent
with the group theoretical analysis predicted for tetragonal symmetry I4/m (point group
5
C4h ). 57Fe Mössbauer spectra recorded at room temperature show a paramagnetic behavior for
Sr1.50Ca1.50Fe2.25Mo0.75O9–, and magnetic ordering for Sr1.92Ca1.08Fe2.04W0.96O9–. The isomer
shift () and quadrupole splitting () values are characteristic of high-spin Fe3+ in a distorted
octahedral coordination.

Este trabajo trata sobre la primera aplicación del análisis mediante fluorescencia de rayos X por dispersión de energías (EDXRF) al estudio de pinturas murales de época romana en Cataluña. En el estudio, han sido analizados varios fragmentos decorados (relacionados con las pinturas de las estancias de la domus de Iesso, datada del s. II d. C.) en orden a determinar cuales fueron los elementos causantes de las distintas tonalidades así como realizar la caracterización de los materiales de soporte. Con el fin de confirmar y ampliar los resultados obtenidos mediante EDXRF, se han utilizado otras técnicas de análisis como la microscopía óptica de polarización (POM), la difracción de rayos X (XRD) y la microscopía electrónica de barrido con sistema de análisis de dispersión de energías acoplado (SEM-EDS). Las muestras del estudio presentan una gama de colores restringida constituida por colores rojo, ocre, verde, blanco y negro, todos ellos en distintas tonalidades. Los resultados obtenidos sugieren que se empleó una paleta con presencia de minerales clásicos de origen local. Aunque los colores rojos están principalmente compuestos por hematites se ha detectado la presencia de plomo en algunos espectros (que podría indicar o bien el uso de rojo de plomo o bien la utilización de blanco de plomo para la preparación de pigmentos); los amarillos y los verdes se obtuvieron a partir de óxidos de hierro que dan estas tonalidades; los blancos se elaboraron con calcita; y finalmente los colores negros no parecen ser de origen mineral. El estudio de los morteros utilizados en el estucado, realizado fundamentalmente mediante POM y SEM-EDS, ha puesto de manifiesto el uso de morteros de cal de diferente granulometría aplicados en capas superpuestas.

A small plate of oil on copper painting from the Italian Renaissance period was characterized by means of noninvasive spectroscopic methods. The study was conducted by the use of energy-dispersive X-ray fluorescence, X-ray diffraction, and Raman and diffuse reflectance infrared Fourier transform spectroscopies to determine the technology production process in such kinds of artworks. Results allowed us to characterize the copper alloy of the support media; the preparation layer, which is composed by white lead; and the pictorial layer of variable composition (green copper sulphate compounds, red lead, carbon black, brown earth pigments, gold, vermilion, and white lead). The complementarity of the techniques used in this study has proven to be highly effective.

Molecular iodine is photoexcited by a strong 800-nm laser driving several channels of multiphoton excitation. The motion following photoexcitation is probed using time-resolved x-ray scattering, which produces a scattering map SðQ; τÞ. Temporal Fourier-transform methods are employed to obtain a frequency-resolved x-ray-scattering signalSðQ; ωÞ. Taken together, SðQ; τÞ andSðQ; ωÞ separate different modes of motion so that mode-specific nuclear oscillatory positions, oscillation amplitudes, directions of motion, and times may be measured accurately. Molecular dissociations likewise have a distinct signature, which may be used to identify both velocities and dissociation time shifts and also can reveal laser-induced couplings among the molecular potentials.

Tesina elaborata su uno specifico tema, utile per il corso di Chimica Applicata ai Beni Culturali della Prof.ssa Chillura Martino, inserito nel Piano di Studi del Corso di Laurea Magistrale di Archeologia dell'Università di Palermo (anno accademico 2016/17).

This paper shows evidence of the capability of electron backscatter diffraction (EBSD) to accurately estimate the magnetocrystalline anisotropy energy (MAE) of API 5L steels. The crystallographic texture of five circular steel samples was characterized by X-ray global texture and EBSD microtexture measurements. The average MAE of each one of these samples was estimated from the set of individual grain orientations obtained from orientation maps measured by EBSD. The angular dependence of EBSD-derived MAE was compared with predictions made from X-ray texture and Barkhausen noise (BHN) measurements. The average MAE determined from the EBSD data is in good agreement with the predictions made from X-ray and BHN measurements for all the studied samples. This agreement can be explained by the fact that the number of grains used to predict the average MAE from the EBSD results was statistically sufficient to reproduce the MAE predicted by the other two methods. The EBSD measurement strategy for the accurate MAE estimation was established in terms of parameters such as the number of individual grain orientations to be measured, the sample's texture acuity and grain size, the use of equivalent orientations given by the statistical orthorhombic symmetry of the studied samples, and different measurement planes.

Tujuan dari penelitian ini adalah untuk mengeksplorasi konsep baru mengenai self-healing dengan menggunakan jamur sebagai agen self-healing yang mampu mendorong terjadinya pengendapan mineral kalsium untuk mengisi retakan pada beton. Meskipun banyak jamur telah dilaporkan mampu mendorong terjadinya mineralisasi kalsium, belum dilakukan investigasi mengenai aplikasi proses tersebut pada perbaikan beton, sehingga pemilahan awal pada berbagai spesies jamur telah dilakukan. Hasil eksperimen menunjukkan bahwa, sebagai akibat dari pelelehan Ca(OH)2 dari beton, pH dari medium pertumbuhan meningkat dari 6.5 sampai 13.0. Meskipun terjadi peningkatan pH secara drastis, spora Trichoderma reesei (ATCC13631) tetap dapat berkecambah menjadi miselium dan bertumbuh secara sama baiknya, entah ada maupun tidak ada beton. Teknik karakterisasi material digunakan pada penelitian ini, seperti difraksi sinar X dan scanning electron microscope (SEM), keduanya membuktikan bahwa kristal yang diendapkan dari hifa jamur tersusun atas kalsit.