X-ray Diffraction Research Papers - Academia.edu (original) (raw)

Self Portrait at an Easel (1660) was examined in the
laboratory in 2007. This study revealed that the work had retained
its original format and that it was probably painted while stretched
inside a wooden frame. This stretcher, and not a wooden panel, is
depicted on the right of the painting: Rembrandt thus portrayed
himself in the act of painting. The pigments seen on the palette
were analysed using X-ray fluorescence and X-ray diffraction: these
pigments, as well as a black pigment, were the only ones used by
the artist for this painting. A paint sample was taken to make a
stratigraphic study of the paint layers.

- by
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- X-Ray Fluorescence (XRF) Spectroscopy, Self-Portraits, X-ray Diffraction, Artists Palette

Radio wave signals do not travel in a straight line path. There may be some obstacles between the source
and the destination which cause diffraction, reflection, scattering and attenuation. There are some types of
obstacles such as knife edge, wedges and round edges. This paper shows the diffraction loss caused by
wedges based on Uniformal Theory of Diffraction (UTD) given in (ITU-R Recommendation P.526-12)
using Matlab software. It could be said that this is an important method because radio waves travel over
wedge shaped roofs of buildings and corners of the buildings. In addition this diffraction loss changes for
both roofs and corners for a particular obstruction material. Furthermore, the electrical properties of the
wedge shaped obstacles are affecting the diffraction loss such as conductivity and dielectric constant. The
result shows that higher conductivity leads to have a higher amplitude oscillation at the receiver

- by Bawar Abid Abdalla and +1
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- Antennas & Radio Wave Propagation, X-ray Diffraction, Wedge Instability, Microwave and Millimeter waves Antennas

Boron doped and undoped Poly(vinyl) alcohol/Zirconium-yttrium acetate (PVA/Zr-Y) nanofibers were prepared by electrospinning using PVA as a precursor. The effect of boron doping was investigated in terms of solution properties, morphological changes and thermal properties. The effect of boron doping on calcined yttria stabilized zirconia (YSZ) fibers were evaluated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy analysis. XRD
analysis revealed varying amounts of monoclinic and tetragonal zirconia present in the undoped fibers calcined at 800oC. The average crystallite sizes of the undoped YSZ were increased from 9.28 to 22.79 nm with calcining temperature increasing from 250 to 800 °C. The crystallite size was enhanced with boron doping. The systematic evolution of morphological features in the spun and the processed fibers were employed by scanning electron microscopy.

- by Prof.Dr. İbrahim USLU
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- Polymer Chemistry, Polymer science, Green Chemistry, Ceramics (Ceramics)

Aluminium carbide (Al4C3) has gained extensive attention due to its abrasive and creep resistance properties. Aim of the present study was to evaluate the impact of biofield treatment on physical and structural properties of Al4C3 powder. The Al4C3 powder was divided into two parts i.e. control and treated. Control part was remained as untreated and treated part received biofield treatment. Subsequently, control and treated Al4C3 samples were characterized using X-ray diffraction (XRD), surface area analyser and Fourier transform infrared spectroscopy (FT-IR). XRD data revealed that lattice parameter and unit cell volume of treated Al4C3 samples were increased by 0.33 and 0.66% respectively, as compared to control. The density of treated Al4C3 samples was reduced upto 0.65% as compared to control. In addition, the molecular weight and crystallite size of treated Al4C3 samples were increased upto 0.66 and 249.53% respectively as compared to control. Furthermore, surface area of treated Al4C3 sample was increased by 5% as compared to control. The FT-IR spectra revealed no significant change in absorption peaks of treated Al4C3 samples as compared to control. Thus, XRD and surface area results suggest that biofield treatment has substantially altered the physical and structural properties of treated Al4C3 powder.

- by Mahendra Kumar Trivedi and +2
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- X-ray Diffraction, Crystallite Size, Lattice Parameter, Tensile Stress
- by Antoni Sanchez-Ferrer
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- Optics, Laser, Microsystems, Solid State NMR

Hydroxyapatite (HAP) is a substance that is most actively used in orthopedia and dentistry as a biocoating of implants in order to improve its osteointegration with bone tissue. HAP was synthesized by precipitation technique with the use of the biological source-hen's eggshell. X-ray diffraction (XRD) investigations, IR-spectroscopy, scanning electron microscopy (SEM) demonstrate that the obtained powder-like material in the form of globules from 4 to 5 mm in size is single-phase, thermally stable up to 900 1C and morphologically uniform. The globules consist of nanocrystals with the average size of about 30 nm.

- by Dmitry Goloshchapov
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- Biomaterials, Hydroxyapatite, X-ray Diffraction, Near Infrared Spectroscopy

A facile template-free solvothermal strategy has been developed to synthesize Eu(III)-based coordination polymer (CP) hollow spheres, using N, N-dimethylformamide (DMF) as a solvent and 2-aminoterephthalic acid (H2ATPA) as a ligand. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), elemental analyses (EA), Fourier transform infrared (FT-IR), Brunauer− Emmett−Teller (BET), and thermogravimetric analysis (TGA). SEM and TEM results show that the Eu-ATPA hollow microspheres have diameters of 200–400 nm and a thickness of about 15–30 nm. Besides, the photoluminescence (PL) properties of the Eu-ATPA hollow microspheres have been investigated in 100-300 K. Results show that the luminescence intensity of Eu-ATPA hollow microspheres decreases dramatically with the increase of temperature between 100 K and 300 K. To investigate the ligand effect on luminescence properties and morphology of the products, a series of Eu-based CPs built from 1,4-benzenedicarboxylate (BDC) and its derivatives have been fabricated. The results demonstrate that the morphologies of the products are sharply different from each other, indicating that their morphologies are ligand-dependent. The emission spectra, quantum yields, and the fluorescence decay curves reveal that the product has the strongest fluorescence intensity when BDC was used as the ligand. Moreover, the luminescence intensity of the products built from electron-withdrawing groups substituted BDC is stronger than those built from electron-donating groups substituted BDC. The order of the fluorescence lifetime and measured photoluminescence quantum yield (PLQY) of the samples is fundamentally the same as the order of the fluorescence intensity.

- by Jacobs Publishers and +1
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- Chemistry, Inorganic Chemistry, Polymers, Nanostructured materials
- by Harries Muthurajan
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- Electron Microscopy, X-ray Diffraction, Ceramics, Precipitation

In this paper we approach the study of a ceramic recipe based on the addition of crushed spathic calcite as temper. We first briefly discuss the anthropological significance underlying the identification of technological paste recipes, as well as the spatial distribution of the spathic calcite recipe in the Mediterranean basin. Subsequently, we focus on the possibilities of identifying this recipe using several analytical methods, including binocular microscopy, image analysis, petrology, X-ray powder diffraction and X-ray fluorescence. Thus, the complementarity existing between different methods commonly applied in pottery analysis is considered in order to know the potential of these various techniques to identify spathic calcite recipe and classify the ceramic record to maximize the social archaeological interpretation of the data. The final objective is to know the feasibility and limitations that certain analytical procedures - such as the binocular microscopy- have for extrapolating the identification of this recipe to a larger series of ceramics from only certain features of the paste.

- by Daniel Albero Santacreu
- •
- Archaeology, Prehistoric Archaeology, Pottery (Archaeology), Petrology
- by Gilberto Artioli and +1
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- Crystallography, X-ray Diffraction, Zeolites
- by Assoman KOUAKOU
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- Pharmacology, Chemistry, Organic Chemistry, X-ray Diffraction

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.

- by SAID LOUIHI
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- Mössbauer Spectroscopy, Raman Spectroscopy, X-ray Diffraction
- by IOSR Journals
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- Physics, Chemistry, X-ray Diffraction, Optical band gap

Electrical discharge machining (EDM) is one of most popular nonconventional machining processes used for creating complex shapes within the parts and assemblies in the manufacturing industry. The present work deals with studying the effect of EDM input parameters (peak current, pulse-on time and the type of electrode) and the shot blast peening time on the induced surface residual stresses. The response surface methodology (RSM) has been used to plan the experiments. To verify the experimental results, analysis of variance (ANOVA) was used and regression models were built to predict the EDM output performance characteristics for the residual stresses for AISI D2 die steel in terms of input parameters. The results showed that maximum compressive surface residual stresses obtained when using the copper and graphite electrodes with minimum values of pulse current (8 A), pulse on duration (120 µs) and shooting time (60 min.), reaches (-847.636 MPa) and (-637.073 MPa), respectively. These results indicated that the copper electrodes improve the residual stresses by about (33%) compared with graphite.

ZnO nanoparticles and Cu-doped ZnO nanoparti-cles were prepared by co-precipitation method. Also, a part of the pure ZnO nanoparticles were annealed at 750 °C for 3, 6, and 9 h. X-ray diffraction studies were carried out and the lattice parameters, unit cell volume, interplanar spacing, and Young's modulus were calculated for all the samples, and also the crystallite size was found using the Scherrer method. X-ray peak broadening analysis was used to estimate the crystallite sizes and the strain using the Williamson–Hall (W–H) method and the size–strain plot (SSP) method. Stress and the energy density were calculated using the W–H method assuming different models such as uniform deformation model, uniform strain deformation model, uniform deformation energy density model, and the SSP method. Optical absorption properties of the samples were understood from their UV–visible spectra. Photocatalytic activities of ZnO and 5 % Cu-doped ZnO were observed by the degradation of methylene blue dye in aqueous medium under the irradiation of 20-W compact fluorescent lamp for an hour.

- by Neena Prasad
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- X-ray Diffraction
- by Sanjay Sali
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- Materials Science, Chemistry, X-ray Diffraction, Pyrohydrolysis

Exams of Crystallographie

- by Marcio Nascimento
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- X-ray Physics, X-ray Diffraction

Nechytaylo V. B. Optical and Electrochemical Properties of Structures with Variable Composition and Valency on the base of transition metal oxides and cyanoferrates. - Manuscript.
Thesis for Candidate's Degree in Physics and Mathematics on the Speciality 01.04.07 - Solid State Physics. Institute of Physics of NAS of Ukraine, Kyiv, 2004.
The results of experimental studies of the structure, optical and electrochemical properties of the ferric, cobalt, nickel, cupric aquapentacyanoferrates and tungsten trioxide are reported. A new approach for a modification of composition and properties of ferric hexacyanoferrate (FHCF)-like compounds has been developed. Electrochromic effect in ferric aquapentacyanoferrate (FAPCF) films has been discovered and studied. The suggestion on the reasons of the differences in the electrochromic behavior of FAPCF and FHCF has been made. The formation of the nanostructures of cobalt, nickel, cupric hexa- and aquapenta- cyanoferrates inside mesoporous MCM-41 template is shown. Factors that control the response time and cycle life of tungsten trioxide electrochromic devices are investigated. A new electrochromic device, in which the great stability of tungsten trioxide film is ensured, has been developed.
Key words: electrochromic effect, tungsten trioxide, Prussian blue, thin films, porous materials, nanostructures, MCM-41.

- by Volodymyr Nechytailo
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- Structure, Spectroscopy, X-ray Diffraction, Electrochromism

In order to contribute to the valuation of clay materials from the Zinder Region, the clays taken from the quarry and used for the pottery of Mirriah have been characterized from a physico-chemical and mineralogical point of view. So the five samples were taken and the composite sample representative of the quarry were subjected to chemical and mineralogical analyzes.The chemical analysis showed that the six samples all consisted of more than 60% aluminosilicates with a high silica/alumina ratio estimated at 2.5 on average. This report shows that the samples of this study are rich in clay minerals; this is in agreement with the estimate of the fine or clay fraction which is 39.5% of the initial mass of the raw sample. This chemical analysis also made it European Scientific Journal, ESJ ISSN: 1857-7881 (Print) e - ISSN 1857-7431 January 2021 edition Vol.17, No.3 www.eujournal.org 122 possible to highlight, at the level of these Mirriah clays, a significant iron oxide content of 32%, which gives them a brick red color. The main mineralogical phases detected by X-ray diffraction in the raw sample and its fine fraction are kaolinite, a mica structure close to illite and quartz, all weathering products of granite. This characterization indicates that the clays mined at the Mirriah quarry are very favorable materials for formulations of pottery products.

- by European Scientific Journal ESJ
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- X-ray Diffraction, Pottery, Clays, Chemical Analysis
- by Parth P
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- Scanning Electron Microscopy, X-ray Diffraction, Fly Ash, BET surface area
- by Pandian M S
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- Mineralogy, Petrology and Geochemistry, X-ray Diffraction, Ore Geology

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.

Tutankhamun's golden mask and throne were investigated by an improved XRDF setup, which was specially designed for this study. XRD pattern and XRF data were taken non-destructively from one small site (2mmtD) in air under contact free condition.
Golden sheets forming the golden mask were confirmed tobe23 K, and the surface of the sheet, used for shaping its face, was coated with a very thin layer of 18 K (28 nm) white gold. The mask and throne were decorated with artificial glass,v materials in many shades of blue, and with precious stones such as obsidian, magnesite, carnelian, lapis lazuli, amazonite and alabaster.
Eighteen K gold alloy and dark blue glass were prepared successfullv for reproducing two individual colors on the golden mask, i.e. white gold on the face, and dark blue on the Nemes (headdress).

H13 tool steel with excellent hot working properties is commonly used for manufacturing dies. However, the damage of die surface due to cyclic thermo-mechanical loading is detrimental to the service life. In order to enhance the die life, it has been observed that cladding based repair is superior to welding or thermal spraying repair techniques. In this paper, experimental study of laser cladding of H13 has been carried out. CPM 9V steel powder has been deposited on H13 tool steel plate for repairing the die surface damage using a CW CO 2 laser in conjunction with powder injection system. The effect of laser parameters on clad geometry and clad quality has been investigated. The microstructure of laser cladded samples has been characterized using optical microscope (OM) and scanning electron microscope (SEM). The phases and the residual stresses present in the clad have been determined via X-ray diffraction. The micro-hardness profiles obtained in the clad–substrate system and the hardness change due to cyclic thermal loading have also been characterized. Optical micrographs of the clad microstructure shows existence of vanadium carbide particles embedded in martensite and retained austenite. The hard vanadium carbide particles increase the clad hardness to an average of four times greater than the substrate hardness. It has been observed that compressive residual stresses are generated in clad which is desirable for repair applications as it will impede the crack propagation resulting in enhanced die life.

The presented work primarily focuses on both the damascene
and patination technique which are archaeometallurgically
treated within the framework of the Bronze Age
north of the Alps. The aspect of patination is here perceived
as a pure artificial procedure. On the one hand the investigation
should reveal how damascenings were realized on
bronze objects and if the observations provide evidence for
clarifying the provenance of the rarely used inlay technique
– a major question that is still unsolved. On the other hand
authentic methods are to be examined in detail that once
presumably allowed the patination of prehistoric damascened
items for enhancing the weak color contrasts between
base metals and inlays.
First of all the study shows that metal inserts were not
used frequently throughout the whole Bronze Age and in
the different areas north of the Alps. There were longer
gaps between the various stages of the era. In contrast platings
as a special form of damascening (»surface damascening
«) were applied continuously since period Montelius
II, yet this decoration is only a characteristic feature for the
Nordic circle that was not adopted in southern regions.
Using only electron as decoration metal throughout the
entire Bronze Age platings differ from damascenings with
metal inlays (»inlaid damascening«) in another point that
besides gold or electron they mainly availed of unalloyed
copper. Later the spectrum of inlaid damascenings was
enlarged by pewter, bronze, and iron. The investigation
demonstrates furthermore that the cavities for inlays on
most objects were already designed prior casting. However,
multiple evidence is found for reworking cast grooves. Only
in some cases the grooves were made exclusively by chasing
or engraving.
For Late Bronze Age artifacts it becomes clear on account
of stylistic and technical characteristics that the metal inlay
technique was practiced only by few workshops, nevertheless
probably having influenced each other. Such considerations
are much more difficult to proof for the Early and
Middle Bronze Age as there are less damascened pieces. Yet,
similar decoration patterns and techniques suggest interactions
between single craftsmen or workshops. Unfortunately,
the provenance of the damascene technique still
remains unclear despite this new investigation. Though, it
is at least unlikely that the polychrome decoration was
directly adopted from Mediterranean or even Greek prototypes,
but the stimulations rather have to be searched in the
Carpathian region. Finally, also a selfcontained development
somewhere in Central or Northern Europe cannot be
completely ruled out.
On the basis of patination experiments it can be shown
that in fact human urine is suitable for coloration of damascened
objects with copper inlays. Ideally, the medium produces
purple-black patinas on unalloyed copper while the
addition of elements such as tin or arsenic to copper gives
somewhat lighter appearances. High concentrations of tin
result in light yellow or slightly green-gray coatings. Even
these colors may have been desired in prehistory on tin
bronzes as they perfectly contrast with purple-blackish
patinated copper inlays. The investigated method therefore
emerges as a possible and formerly neglected way for patinating
many damascenings of the Bronze Age north of the
Alps. For this, however, some preconditions have to be fulfilled
which are discussed in detail in the following work.

Cueva de Ardales in Málaga, Spain, is one of the richest and best-preserved Paleolithic painted caves of southwestern Europe, containing over a thousand graphic representations. Here, we study the red pigment in panel II.A.3 of "Sala de las Estrellas," dated by U-Th to the Middle Paleolithic, to determine its composition, verify its anthropogenic nature, infer the associated behaviors, and discuss their implications. Using optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction, we analyzed a set of samples from the panel and compared them to natural coloring materials collected from the floor and walls of the cave. The conspicuously different texture and composition of the geological samples indicates that the pigments used in the paintings do not come from the outcrops of colorant material known in the cave. We confirm that the paintings are not the result of natural processes and show that the composition of the paint is consistent with the artistic activity being recurrent. Our results strengthen the hypothesis that Neanderthals symbolically used these paintings and the large stalagmitic dome harboring them over an extended time span.

- by Africa Pitarch and +3
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- Rock Art (Archaeology), Symbolism, Scanning Electron Microscopy, Archaeology of the Iberian Peninsula

Authentication of coins is frequently presenting complicated problem in numismatics practice. Metal composition only may not be enough to identify forgeries, notably when one deals with noble metals-silver, gold or electron. Isotopic ratios, providing in certain cases information regarding metallic ore source (geographical provenance), require a sample to be extracted for MS-analysis while sampling is not permissible for numismatic material in principle. To solve the problem it becomes crucial, in addition to metal's composition, to establish the method used for a coin's manufacturing, as forgers are rarely realizing or following the method that was used in the original historical production. Conventional visual studying under microscope is not always being enough to understand how the coin was produced while metallographic examination of polished and etched metal samples, which might provide necessary information, is not applicable here for its destructive character. Necessary information regarding manufacturing could have been extracted from residual stress analysis, but, in general, there were very few published works regarding this kind of analysis for coins, and those few did not consider any connection between manufacturing process and residual stress in metal. The expected types of residual elastic stress arisen under historically known methods of coins production (casting in hot or cold mold, striking hot or cold metal) are considered in this work. On this base, non-destructive X-rays diffraction method (Sin 2 Ψ-method) is offered to distinguish between various methods of manufacturing. The results may be applied in museum's laboratory as useful criterion for authentication of coins and medals.

- by Alexander Kossolapov
- •
- Authentication, X-ray Diffraction, Residual Stresses, Coins

Polyethylene terephthalate is one of the important synthetic ester polymeric material used in widespread areas. In textile industry, this fibrous material finds use in most of the garment and apparel applications due to its ease of handling, maintenance, and drying and competes with cotton materials. However, due to the maximum hydrophobic behavior, this textile material gives number of issues like accumulation of statics, negligible moisture content, poor comfort and aesthetic characters. Hence, in order to use this polyester material in the general textile industries particularly for garment and apparel productions, it is necessary to increase to some extent of its hydrophilic character by the application of some suitable chemicals like polyvinyl alcohol. In these context, in this work an attempt is made to treat the polyethylene terephthalate fabric with sodium hydroxide followed by polyvinyl alcohol so as to increase the aesthetic properties. The output received after the polyvinyl alcohol treatment on this fabric gives the good results expected for the garment applications.

The phase problem is a persistent bottleneck that impedes the structure-determination pipeline and must be solved to obtain atomic resolution crystal structures of macromolecules. Although molecular replacement has become the predominant method of solving the phase problem, many scenarios still exist in which experimental phasing is needed. Here, a proof-of-concept study is presented that shows the efficacy of using tetrabromoterephthalic acid (B4C) as an experimental phasing compound. Incorporating B4C into the crystal lattice using co-crystallization, the crystal structure of hen egg-white lysozyme was solved using MAD phasing. The strong anomalous signal generated by its four Br atoms coupled with its compatibility with commonly used crystallization reagents render B4C an effective experimental phasing compound that can be used to overcome the phase problem.

Zinc batteries are a more sustainable alternative to lithium-ion batteries due to its components being highly recyclable. With the improvements in the screen printing technology, high quality devices can be printed with at high throughput and precision at a lower cost compared to those manufactured using lithographic techniques. In this paper we describe the fabrication and characterization of printed zinc batteries. Different binder materials such as polyvinyl pyrrolidone (PVP) and polyvinyl butyral (PVB), were used to fabricate the electrodes. The electrodes were first evaluated using threeelectrode cyclic voltammetry, x-ray diffraction (XRD), and scanning electron microscopy before being fully assembled and tested using charge-discharge test and two-electrode cyclic voltammetry. The results show that the printed ZnO electrode with PVB as binder performed better than PVP-based ZnO. The XRD data prove that the electro-active materials were successfully transferred to the sample. However, based on the evaluation, the results show that the cathode electrode was dominated by the silver instead of Ni(OH)2, which leads the sample to behave like a silver-zinc battery instead of a nickel-zinc battery. Nevertheless, the printed zinc battery electrodes were successfully evaluated, and more current collector materials for cathode should be explored for printed nickel-zinc batteries.

- by beei iaes and +1
- •
- Cyclic Voltammetry, X-ray Diffraction, Screen printing, polyvinyl butyral

This paper presents a chemical characterization by means of WDXRF and mineralogical characterization by means of XRD of 21 individuals of black gloss pottery from the excavations on the acropolis of Populonia. The results shed new light on the circulation of pottery to this major urban centre in North Etruria during the Roman Republican period, while they also suggest the likelihood of local manufacture. In particular, we identify at Populonia four different black gloss productions that can be archaeometrically defined as Campanian A, Volterra, Etrusco-Latial 1 and a possible local production of ceramics belonging to the Petites Estampilles Group, active in the late fourth and third centuries BCE. Once thought to be a workshop located at Rome itself, this class is now understood as a diffuse network of workshops located in South Etruria and Latium producing pottery of similar technology and style. The present study potentially extends the map of its production to North Etruria in a region at that time newly incorporated into the expanding Roman Republican empire.

- by Alejandro G. Sinner and +3
- •
- Archaeology, Classical Archaeology, Archaeometry, Archaeology of pre-Roman Italy

The site of Caltagirone is one of the major production center of pottery in Sicily and southern Italy, and its activity is attested since Neolithic period and is still a vivid tradition. From the specifics requirements of master craftsman to individuate the relation between the cooking process and the color of their artifacts, a project based on the study of this two parameters correlations is developed. In order to create ceramic specimens with a composition typical of the area of interest, clay were sampled in the quarry of Monte San Giorgio and in the area of Lazzaretto (Conadomini furnace). The sand used as inert was sampled from the Monte Stagno quarry; all the sites were chooses following the indications of the major ceramists of Caltagirone. In this work we present the results from the color specification of two types of mixture that characterize the Calatina production used by ceramicists to obtain, respectively, ceramics commonly used and most valuable artifacts. The specimens were subjected to cooking varying the maximum temperature from 400 °C to 1200°C and then to color measurements with spectrophotometric method recording the trend of the spectral reflectance factor and the values of CIELAB colorimetric space.
The color differences were calculated in reference to the sample before cooking, settled "raw". The results obtained represent a set of objective data on color changes of ceramic specimens due to the different cooking conditions and they gave precise information for the continuation of research. The study also provides to cross the colorimetric results with those obtained by X-ray diffraction techniques. This is useful to identify, for each thermal processes, the mineralogical phases that may be responsible of the color differences measured.

Utilising the characteristics of x-ray radiation, the internal structure of certain materials can be investigated using various techniques. A LD Didactic X-ray Apparatus was used in combination with a selection of radiation sources and detectors to investigate the properties of metals and compounds using two basic theories: Moseley's Law and Bragg's diffraction law. A series of experiments were conducted to determine the theory's validity, and the value of the Rydberg constant was determined to be (10.32 ± 0.71) × 10 6 m −1 .

- by Andrew D Miller
- •
- X-ray Diffraction, Rydberg constant, Bragg's Law

Analisis Difraksi Sinar-X (X-ray Diffraction) merupakan metode karakterisasi material yang digunakan untuk
mengidentifikasi fase kristalin material dengan cara menentukan parameter struktur kisi serta untuk mendapatkan
ukuran partikel

- by suhufa alfarisa
- •
- X-ray Diffraction

Effect of w–d cycles (C) on the strength and microstructural changes of RAP-FA blend and RAP-FA geopolymer. Micro-structure analyzed using XRD and SEM. For C < 6, the w–d cycles stimulate the chemical reaction and hence strength improvement. For C > 6, the significant macro-and micro-cracks developed during w–d cycles cause strength reduction. UCS after w–d cycles of RAP-FA geopolymers and RAP-FA blends were compared with road authorities' requirements. a b s t r a c t The usage of recycled asphalt pavement (RAP) and fly ash (FA) in pavement applications contributes to the sustainable usage of such waste by-products. Although RAP-FA geopolymer and RAP-FA blend without liquid alkaline activator have been proven as a pavement material based on strength and leachate requirement, the durability of these by-products when exposed to an aggressive environment has not been investigated to date. This research investigates the effect of wetting–drying (w–d) cycles on the strength and microstructural changes of RAP-FA blend and RAP-FA geopolymer. The strength characteristics of these materials were determined by unconfined compression strength (UCS) test. The micro-structure of the compound pavement material was also analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Test results show that the UCS of RAP-FA blend increases with increasing the number of wetting–drying (w–d) cycles (C), reaching its peak at 6 w–d cycles. The XRD and SEM analyses indicate that the increased UCS of RAP-FA blend is due to stimulation of the chemical reaction between the high amount of Calcium in RAP and the high amount of Silica and Alumina in FA during w–d cycles leading to production of more Calcium (Aluminate) Silicate Hydrate [C–(A)-S-H]. For C > 6, the significant macro-and micro-cracks developed during w–d cycles cause strength reduction. For RAP-FA geopolymer, geopolymerization products [Sodium Alumino-Silicate Hydrate, N-AS -H] co-existed with C-(A)-S-H results in increased UCS within the first 6 w–d cycles. The macro-and micro-cracks when C > 6 cause strength reduction of RAP-FA geopolymers. A better durability performance is observed when RAP-FA geopolymers are prepared with higher NaOH content that can be attributed to formation of a stable cross-linked alumino-silicate polymer structure. The outcome from this research confirms the viability of using RAP-FA blends and RAP-FA geopolymer as alternative sustainable pavement materials.