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Three-membered rings (3-rings) are an important structural motif in zeolite chemistry, but their formation remains serendipitous in reticular chemistry when designing zeolitic imidazolate frameworks (ZIFs). Herein, we report a design principle for constructing four new ZIFs, termed ZIF-1001 to -1004, from tetrahedral Zn

The changes in the properties of the supercapacitor electrode material copper cobaltite, prepared by a simple hydrothermal procedure, were investigated upon doping with Mo with different ratios (CuCo1-xMoxO4, x = 0.0, 0.1, 0.2). The effect of doping on the structural, microstructural parameters, cation distribution was studied using Rietveld analysis for x-ray diffraction patterns. Results evidenced the incorporation of Mo6+ ions substitutionally for Co3+ ions, which is confirmed by the vibrational bands obtained from Fourier transform infrared spectrometry and by the vibrating sample magnetometer measurements. The particle morphology and size distribution of the samples were investigated using high-resolution transmission electron microscope (HRTEM) imaging. The influence of Mo-doping on the absorbance behavior of copper cobaltite was examined utilizing measured absorbance diffused spectra; the bandgap structure of doped samples was greatly affected. The changes that occurred in the optical band gap upon doping were explained using the Burstein–Moss shift effect. The photoluminescence intensity was affected by the amount of Mo doping. The samples emitted violet, blue, and yellow colors depending on the amount of doping.

XAFS/XRF is a general-purpose absorption spectroscopy beamline at the Synchrotron-light for Experimental Science and Applications in the Middle East (SESAME), Jordan. Herein, its optical layout is presented along with its powerful capabilities in collecting absorption and fluorescence spectra within a wide energy range (4.7–30 keV). The beamline is equipped with a conventional fixed-exit double-crystal monochromator that allows the collection of an X-ray absorption spectrum within a few minutes in step-by-step mode. An on-the-fly scanning mode will be implemented shortly where the acquisition time will be reduced to less than a minute per scan. The full automation of the beamline allows performing successive measurements under different conditions. The different experimental setups and special features available to users are reported. Examples of XRF and XAFS measurements are presented, showing the performance of the beamline under different standard conditions.

Nanocomposites of CdS@CuS heterostructures were synthesized applying a simple chemical procedure. The structural characteristics of resulting nanocomposites (1 − x)CdS–xCuS (x = 0, 0.3, 0.5, 0.7 and 1) samples were inferred applying synchrotron X-ray diffraction (XRD), Fourier transform infrared (FTIR) and high-resolution transmission electron microscope techniques. The optical characteristics were deduced from the UV–Vis and photoluminescence (PL) spectroscopy techniques. XRD phase identification revealed CuS having the hexagonal phase P 63/m m c, while CdS in two phases: cubic major phase $$ F \bar{4} 3 m $$ and hexagonal minor phase P 63 m c. The phase percentage, the crystallite size, the lattice parameters and the ions coordinates of each phase are traced as a function of the alloying parameter (x). FTIR analysis revealed a change in the transmittance intensity of the vibration bands upon changing CdS/CuS ration in the nanocomposites matrix. UV–Vis absorption spectra were affected greatly by the ratio of CdS to CuS in the different composites. All composites materials exhibited two energy gaps lower than parent compounds. The PL emission of CdS sample is broader than CuS sample. The PL spectra of CdS@CuS nanocomposites samples revealed a broad emission with a redshift depending on the ratio between CdS and CuS in the matrix. All samples emitted UV, violet and blue colors, while CuS sample reveals UV and violet colors. The obtained properties of CdS@CuS nanocomposites, by changing the composition ratio, make them good candidates for enhanced visible light photocatalytic activity and solar energy applications.

Nowadays, Forecasting of automotive Sales sector play a major role in automobile manufacturers which occupy an important valuable and great place in every country around the globe. In this study, we address automotive Sales Forecasting in largest automobile manufacturing company in Egypt after reviewing the most effective variables impact on sales volume such as unit selling price, inflation rate, per capita income, fuel price and previous sale. The model is trained using Neural Networks (ANN), Adaptive Neuro-fuzzy inference system (ANFIS) and Multiple Linear Regressions (MLR) in order to compare and select the best results. Finally, we obtained the results by the proposed model and we found that ANN technique had the superior result compared to others techniques.

We present a detailed description of the SESAME Materials Science (MS) beamline for X-ray diffraction (XRD) applications, presently under construction in Allan, Jordan. The beamline is based on components previously installed at the Swiss Light Source, but modifications in the beamline design have been introduced to match the characteristics of the SESAME storage ring. The SESAME MS beamline will accommodate XRD experiments in the energy range between 5 and 25 keV. The beamline ray tracing analysis at 10 keV estimates the flux at the sample to be of the order of 1013 (photons s−1), the energy resolution is about 2 eV and the effective beam size at the sample of 300 × 2800 µm2. Investigations of microstruture will be possible as the instrumental broadening, resulted from simulating the diffraction pattern for a standard material, is of the order of 0.01° at 15 keV. A wide range of applications will be possible at the beamline, such as powder diffraction studies, single crystals and in situ XRD. The commisioning of the beamline is expected to be in the second half of 2017.

Synchrotron radiation X-ray diffraction (XRD) patterns from an extensively ball-milled iron alloy powder were collected at 100, 200 and 300 K. The results were analysed together with those using extended X-ray absorption fine structure, measured on the same sample at liquid nitrogen temperature (77 K) and at room temperature (300 K), to assess the contribution of static disorder to the Debye–Waller coefficient (Biso). Both techniques give an increase of ∼20% with respect to bulk reference iron, a noticeably smaller difference than reported by most of the literature for similar systems. Besides good quality XRD patterns, proper consideration of the temperature diffuse scattering seems to be the key to accurate values of the Debye–Waller coefficient. Molecular dynamics simulations of nanocrystalline iron aggregates, mapped on the evidence provided by XRD in terms of domain size distribution, shed light on the origin of the observedBisoincrease. The main contribution to the static disorder is given by the grain boundary, while line and point defects have a much smaller effect.

The potential of modern methods for X-ray diffraction Line Profile Analysis can be fully exploited with data collected at synchro- tron radiation beamlines, provided that optics and experimental set-up are suitably designed and characterized. The Material Characterization by X-ray Diffraction beamline, MCX, at Elettra-Sincrotrone Trieste

The catalytic effect of SnO2 doping on the hydrogen thermal desorption of MgH2 was investigated by coupled thermogravimetric-mass spectrometric (TG-MS) analyses, among a set of samples prepared with different SnO2/MgH2 molar ratios. A small release of water and carbon dioxide was detected at temperatures preceding to the reductive thermal decomposition of MgH2 yielding molecular hydrogen. While TG and DTA data collected at different heating rate provided an apparent activation energy for the entire thermal process, appropriate ion- current signals from the MS-data were used to obtain the activation energies of the single chemical reactions yield- ing the formation of H2O, CO2, and H2. The most common equations derived from model-free isoconversion methods (Kissinger-Akahira-Sunose; Flynn-Wall-Ozawa; Starink) were used by processing temperatures referred to the dif- ferent kinds of signals (TG-, DTG-, DTA-, TIC-, molecu- lar-ion IC-curves) for isoconversion points corresponding to the maximum rate of transformation. Temperature and activation energy values were used to compare the kinetic behavior of MgH2 powder with the best performance of a doped sample, prepared by high energy grinding of SnO2/ MgH2 mixture. Doped-MgH2 samples prepared with SnO2 mass ratio of 0.2 showed the best kinetic thermal decomposition behavior, with respect to the pristine MgH2 powder: a decreasing of the main thermal decomposition event of ca. 51-57 C associated to a coherent decreasing of ca. 20 % (ca. 30 kJ mol -1 ) of its activation energy value.

The thermal desorption of hydrogen from commercial MgH2 powders was investigated by coupled thermogravimetry and mass spectroscopy (TG–MS). The analysis of the evolved gas species gives a detailed picture of the composition of the initial specimen and of its thermal decomposition: just before the H2 release from MgH2, additional H2O and CO2 are detected, sensing the presence of MgCO3 and Mg(OH)2 in the initial specimen. Measurements done at different heating rates allowed the determination of apparent activation energies for the whole thermal process. Moreover, by considering appropriate ion current signals of the MS data, the activation energies of the single chemical reactions, leading to the formation of H2O, CO2, and H2, were obtained. Differences coming from the choice of the (model-free isoconversion) method of analysis (Kissinger–Akahira–Sunose; Flynn–Wall–Ozawa; Starink; Friedman equations) are evidenced and discussed.

Nanocrystalline CaF2powder specimens were produced both by co-precipitation of CaCl2and NH4F and by ball milling of a coarse powder. The specimen homogeneity and a detailed picture of the lattice defects can be assessed by the simultaneous analysis of the powder diffraction pattern and of the solid-state19F magic angle spinning NMRT1relaxometry data. While diffraction line profiles provide information on domain size distribution and the content of dislocations,T1relaxometry is more sensitive to inhomogeneity of the powder (large defect-free grainsversusdefective small ones). After extensive milling it is possible to obtain fluorite domains of comparable size to the chemically synthesized CaF2(circa10–12 nm), but with a marked difference in the lattice defect types and content. It is then proved that surface defects (related to domain size), line defects (dislocations) and point (Frenkel) defects have a quite different effect on the powder pattern as well as on theT1spin-lattice relaxation time.

The growth process of nanocrystalline fluorite was studied by in situ synchrotron radiation X-ray diffraction. The two studied samples had comparable crystalline domain size, but quite different content of lattice defects as a result of the different preparation procedures: ball milling of coarse CaF2 powder or coprecipitation of CaCl2 and NH4F. It is shown that the high dislocation density in the ball-milled fluorite is responsible for a recrystallization process above 773 K (500 °C), which is not observed in the chemically synthesized fluorite. The linear thermal expansion coefficients of both nanocrystalline powders, as obtained and also from the in situ X-ray diffraction data, show a smaller increase with temperature than suggested by the literature on coarse-grained fluorite.

The hydrogen desorption properties of Magnesium Hydride (MgH2) ball milled with cassiterite (SnO2) have been investigated by X-ray powder diffraction and thermal analysis. Milling of pure MgH2 leads to a reduction of the desorption temperature (up to 60 K) and of the activation energy, but also to a reduction of the quantity of desorbed hydrogen, referred to the total MgH2 present, from 7.8 down to 4.4 wt%. SnO2 addition preserves the beneficial effects of grinding on the desorption kinetics and limits the decrease of desorbed hydrogen. Best tradeoff – activation energy lowered from 175 to 148 kJ/mol and desorbed hydrogen, referred to the total MgH2 present, lowered from 7.8 to 6.8 wt% – was obtained by co-milling MgH2 with 20 wt% SnO2.

The effect of high-energy ball milling on calcium fluoride was studied by X-ray Diffraction (XRD) Line Profile Analysis (LPA) and Solid State Nuclear Magnetic Resonance (NMR) spin–lattice relaxation. The latter technique is especially useful not only to detect the nonhomogeneous effects of the early stages of mechanical grinding, but is also sensitive to the defect structure of the ball milled powders. When supported by Solid State NMR, XRD LPA unveils fine details of the milling effects on fluorite, in terms of increasing dislocation density and progressive refinement of the crystalline size down to the nanoscale.

The correlation between the thermoluminescence (TL) response of nanocrystalline LiF and its microstructure was studied. To investigate the detailed TL mechanism, the glow curves of nanocrystalline LiF samples produced by high-energy ball-milling were analyzed. The microstructure of the prepared samples was analyzed by synchrotron X-ray powder diffraction (XRPD) at room temperature. Then, the microstructure of a representative pulverized sample was investigated in detail by performingin situXRPD in both isothermal and non-isothermal modes. In the present study, the dislocations produced by ball-milling alter the microstructure of the lattice where the relative concentration of the vacancies, responsible for the TL response, changes with milling time. An enhancement in the TL response was recorded for nanocrystalline LiF at high-temperature traps (after dislocations recovery starts >425 K). It is also found that vacancies are playing a major role in the dislocations recovery mechanism. Moreover, the interactions among vacancies–dislocations and/or dislocations–dislocations weaken the TL response.