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Considering the importance of micro-structural characteristics of clayey soils on their behavior, the main objective of this research is to investigate the effect of pore fluid properties variations on clayey soils and their physical and micro-structural changes. For experimental purposes, soil-electrolyte solutions with the ratio of 1:50 prepared. A series of physical experiments, as well as, SEM and XRD experiments performed to investigate any variation on the soil behavior due to the changes in pore fluid properties. The results of the physical experiments indicate that, with increasing the electrolyte concentration, one will be faced with a change on the soil behavior including its interaction with water. The SEM pictures indicate that with the presence of sodium ions at low concentration, first soil takes a dispersive structure.  With a further increase in salt concentration, and due to an increase in attractive forces in comparison with repulsive forces within clay particles, a flocculated structure forms. In addition to the above, during this process, a change will happen on the intensity and basal spacing of clay mineral. It is concluded that the main reason for a noticeable change in physical behavior of soil can be attributed mainly to the significant change in electrostatic forces of clay particles.

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Engineering ceramics are often difficult to prepare for observation
because of their hardness, wear resistance and chemical inertness. Different
silicon nitride containing Y2O3 and Al2O3 are prepared and etched using
several different techniques and the most efficient methods are identified.
The microstructure and grain-boundary composition were examined by
electron microscopy (SEM, TEM), electron diffraction and energydispersive
X-ray microanalysis. A method has been developed to quantify
microstructure consisting of elongated, rod like -grains to discuss the
interdependence between starting materials composition, processing
condition, microstructure and resulting mechanical properties of dense Si3N4
materials. It is shown that post-sintering heat-treatment in air in the
temperature between 1100-1450 C results in substantial crystallisation of
the glassy phase.

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In this study, strain and microstructures of quartz grains have been used for deformational analysis of thrust sheets in the eastern Alborz. Structural studies resulted in recognition of eight thrust sheets (Gorgan, Siahkhani, Tazereh, Shahdar, Anbankuh, Shirband, Anjirlu and Sefidkuh) in ascending order from north to south. Microstructural studies and strain analyses on samples across the sheets were carried out for interpretation of deformation conditions. Detail microstructural analysis of quartz grains indicated that the grains are deformed by intracrystalline deformation. Accordingly, it is proposed that the thrust sheets in the southern portion of Tazereh (i.e. Shahdar, Anban-kuh, etc) and the Siahkhani to be generated in shallow depth. However, Tazereh and Gorgan sheets postulated to have deeper origin, presumably from a depth in which the transition from brittle to ductile deformation occurs. The low values of finite strain indicate that emplacement mechanism of the sheets was assumed to be compatible with the model proposed for foreland sheets. That is, the sheets were emplaced on their basal thrust as rigid blocks. Consequently, the area of study is governed by thin skinned tectonics. 

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Gharenaz bentonite contains montmorillonite as the major mineral constituent and Ca as the major exchangeable cation. In the present study, the structural changes occurred in the course of acid activation of this bentonite was investigated by chemical analysis using  ICP-AES and phase analysis using XRD methods. Chemical analysis showed that most of the exchangeable cations i.e. K⁺, Na⁺ and Ca²⁺, can be dissolved at low acid concentration whereas the dissolution of the octahedral layer cations, i.e. Mg²⁺, Fe²⁺ and Al³⁺, depends on the acid concentration. The acid treatment experiments on Gharenaz bentonite by sulfuric acid showed that removal of octahedral cations increases as the acid concentration raises up to 3 normal after which, it remains almost constant. However a further increase in the dissolution of these cations was observed at the acid concentrations more than 5 normal. XRD analysis of the activated samples indicated, i) the elimination of calcite mineral even at low acid concentration. ii) the formation of calcium sulfate (gypsum) and iii) decrease in the intensity of (001) peak of montmorillonite during the activation process, due to the partial destruction of the octahedral layers. In order to evaluate the optimum structural changes, the activated samples was used in bleaching of an edible oil. The results showed that the bentonite activated at 3 normal is most efficient in the bleaching process.

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Kaolinite is non-sensitive, low swelling clay with high chemical resistance and high workability. It is commonly found as a major fraction of clay liner in waste disposal sites. These clay liners are usually exposed to different concentrations of heavy metals. Even though there are several researches focusing on the interaction process of kaolinite and heavy metal contaminations, there are only few researches have been conducted to evaluate the influence of pore fluid properties on the microstructure of clayey soils. Therefore, the aim of this research is to investigate the impact of kaolinite and heavy metal interactions on the microstructure of kaolinite. For this purpose, kaolinite soil were laboratory contaminated with different concentrations of lead and zinc nitrates. Then, with performance of a series of physical and microstructural analysis, the change on the behaviour of contaminated kaolinite is assessed. The result of atterberg limits tests as physical experiment shows that with an increase on the concentration of heavy metal contamination, a decrease on the liquid limit happens. Furthermore, in the presence of high concentrations of zinc and lead ions, due to the formation of flocculated structure and retention of water in macropores of soil, the rate of reduction on the liquid limit decreases. The results of SEM micrograph and the variations on the intensity of the XRD peaks confirm the noticeable change on the microstructure of kaolinite.

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In this article, we have employed GSAS software to do Reitveld profile refinement on XRD patterns from H-T_c superconductor powder YBa2_-xK_xCu₃O_7-y (02. On the other hand, substituting of K instead of Ba led to oxygen depletion and also lowering the Ba (K) plane position along the Z direction (||c). The structural phase ratio of tetragonal to orthorhombic increased and it means that the superconductivity exist even in samples with dominant tetragonal phase.

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Taknar mining district is located about 28 Km northwest of Bardaskan in the central part of Taknar zone.  Taknar Zone is surrounded by Rivash fault in the north and Dorouneh fault to the south. At least 30 percent of Taknar Formation (Ordovician age) is made up of submarine volcanic rocks. Geological evidence indicates that Taknar Zone displaced from another place to present location. Major structural features which are identified included: right lateral strike slip, left lateral strike slip, overturned and reverse faults. Several intrusive rocks were identified within Taknar mining area. Based on the effect of regional metamorphism, intrusive rocks were classified into two major groups: 1- Mid-Late Paleozoic and 2- after Paleozoic. Mid-late Paleozoic is mainly composed of granite, granodiorite and diorite. Based on Al-index, they consist mainly of per-aluminous and minor sub-aluminous, and mid to high in potassium content. Tectonic setting are includes intraplate granite (WPG) and minor volcanic are (VAG). Based on REE content and (La/Yb) N = 9.75-2.15 magma originated from continental crust. Based on magnetic susceptibility, all of them belong to ilmenite series. After Paleozoic intrusive rocks are mainly granite, trondhjemite and quartz monzonite. Except trondhjemite, they are per-aluminous, and the potassium content is mid to high. Spider diagram show enrichment in K, Rb, Ba and Ce and depletion in Sr, Nb, P and Ti. Based on REE content and (La/Yb)N = 6.47-4.87 magma originated from continental

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The Kuh-e-Sarhangi shear zone, with N70°E striking, is the northeastern part of the Kashmar-Kerman tectonic zone locating at the NW of the Lut Block.  The Late Precambrian-Early Cambrian four granitic bodies have been intruded in the Kuh-e-Sarhangi shear zone. The Deh Zaman granite consists of two mezocrat and hololeucocratic bodies that are presenting strong ductile deformation and the mylonitic foliation wich is well developed. This strong mylonitic foliation displays steeply dipping to the NE (S62 ^o E/80^o,). The plunge of the kinkfold axis and rake of the stretching lineation on the mylonitic foliation is about 75^o and 35^o to E-SE, respectively. Micro-structural shear sense indicators including oblique foliation, asymmetric porphyroclast, mica fish and of shear bands that show sinistral sense of shear. Quartz and feldspar microstructures are studied in order to find out  deformational conditions.­ Sub-grain rotation recrystallization (SGR) in quartz grains and brittle deformation to bulging (BLG) recrystallization in feldspar grains indicate 300^oc – 500^oc temperature of deformation that is consistent with green schistto epidote amphibolite facies conditions. These evidences also confirm the delay of deformation with respect to the granite intrusion.

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In this paper, β-PbO nanoparticles were prepared by microwave irradiation. Then, the PbO nanoparticles with size of 32 nm were doped in the Bi_2-xPb_xSr₂Ca₂Cu₄O_y superconductor with x = 0.0, 0.2, 0.4 and 0.6. The samples were synthesized by the standard solid state reaction method. The structural properties, microstructure and morphology of the samples have been studied by XRD and SEM. After synthesizing the samples and observing the Meissner effect, the study of the critical current density (J_c), critical temperature (T_c) and thermogravimetry-differential thermal analysis shows that samples have been down. The results of the critical current density measurements show that the sample with x = 0.4 and an annealing time 60 h has the maximum J_c. Substitution of PbO nanoparticles for Bi reveal that remarkable increases in the critical temperature. The volume of the unit cell of doped samples were increased with respect to that of the undoped samples, which is shown Bi⁺³ substituted by Pb⁺².

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The structural, morphological and magnetic properties of Co_0.5Zn_0.5Fe₂O₄ nanoferrite thin films on glass substrates were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and vibrating sample magnetometer (VSM), respectively. These thin films were deposited by spray pyrolysis method and subsequently calcined at 500 and 600 ˚C. The XRD results reveal that the calcined samples have a single-phase, and their crystallite size and lattice parameter increase as the calcination temperature increases. FE-SEM images exhibit a homogeneous grain size distribution for calcined thin films, and the grains size of samples calcined at 500 and 600 ˚C are ~ 20 and 35 nm respectively. The room temperature magnetic measurements indicate that the magnetization and coercivity of the samples in both parallel and perpendicular direction to applied magnetic field increase with calcination temperature. These can be attributed to the migration of non-magnetic Zn²⁺ ions from octahedral to tetrahedral sites.
 

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In this research, PbFe₁₁Co₁O₁₉ with annealing temperatures of 600, 700, 750, 800, 850 and 900 ˚C at annealing time of 3 h were synthesized by sol-gel method. The structural, microstructure properties and morphology of the samples have been studied by XRD, FT-IR and FESEM. Also, magnetic and dielectric properties of samples were characterized by VSM and LCR meter. The results of measurements of structural show that phase percentage of lead hexaferrite by increasing annealing temperature up to 800 ˚C increase and at annealing temperatures more than 800˚C  percentage this phase decreases. The results of the magnetic measurements of samples reveal that by increasing annealing temperature and by eliminating the second phases,  the saturation magnetization increases. Also, the results of dielectric reveal that by increasing frequency, dielectric constant and dielectric loss decreases which indicates that samples could be suitable for use in devices.  The result measurements show that the best sample is PbFe₁₁Co₁ O₁₉ with annealing temperature of 800 °C and 3 h.

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In this paper, Y-type strontium hxaferrite (Sr₂Co₂Fe₁₂O₂₂) nanostructure with molar ratio of citric acid to metal nitrats of 1:0.5, 1:1, 1:1.5 and 1:2 prepared using a sol-gel of auto-combustion method and then prepared powders were sintering at 1000  ˚C for 3 h. In order to investigate structural, magnetic and dielectric properties of the Sr₂Co₂Fe₁₂O₂₂ nanostructure, samples have been analyzed by X-ray diffraction analysis (XRD), Fourier transforms infrared spectroscopy (FT-IR), scanning electron microscopy field emission (FESEM) , vibrating sample magnetometer (VSM) and LCR meter methodes. The results of measurements of structur show that Y-type hexaferrite structural in the samples with  molar ratios of 1.5 and 2 was completely formed, so that in the sample with molar ratio of 1.5 peaks and its intensity is closer to the standard card. Also, the results of dielectric reveal that by increasing frequency, dielectric constant and dielectric loss decreases which indicates that samples could be suitable for use in devices.  The results show that the best papered sample is at temperature and time of 1000- 3h, respectively, with citric acid mole ratio of 1_.5.

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In this research, the effect of temperature and concentration of bismuth nitrate mole on structural, magnetic and photocatalytic properties of the bismuth ferrite nanoparticles prepared by nitrate-citrate method have been investigated. The structural and magnetic properties were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and vibrating-sample magnetometer at room temperature. An important role in the synthesis of pure bismuth ferrite is played by temperature and excess bismuth oxide. Analysis of XRD patterns and FTIR data indicate that to obtain the pure bismuth ferrite, a stoichiometric amount of bismuth nitrate mole in solution and sintering at temperature 650 °C is needed. The magnetic and photocatalytic results have showed that the presence of the impurity phases led to strong ferromagnetic behavior in samples, but has a negative effect on the photocatalytic properties of bismuth ferrite.

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In this research, the SrMn_xFe_12-xO₁₉ nanoparticles with x = 0.0, 0.5, 1, 1.5 and 2 at 1000 ^oC  for 4 h, using sol-gel method, were synthesized. Thermal analysis, crystalline structure and their bonding properties of the samples by TGA / DTA analysis, XRD and FT-IR were investigated. In order to investigate morphology of the samples from field emission, scanning electron microscopy (FESEM) was used. Also, properties of the samples, using vibrating sample magnetometer (VSM), were investigated. In addition to the Curie temperature of SrMn_xFe_12-xO₁₉ nanoparticles with x = 0.0, 0.5 and 1 was determined. Thermalgravimetric analysis confirms that the formation of the hexagonal phase at temperature of 953.1 ^oC. The results of measurements of the XRD show that the phase percentage of SrMn_xFe_12-xO₁₉ nanoparticles with x = 0.5 has increased. The results of the hysteresis loops of SrMn_xFe_12-xO₁₉ nanoparticles reveal that with increasing Mn contents, the saturation magnetization, remanence magnetization and magnetic coercivity reduced. Also, the results of the magnetization of SrMn_xFe_12-xO₁₉ nanoparticles with temperature reveal that with increasing of Mn contents, the Curie temperature decreased.  

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In this research, molybdenum oxide (α-MoO₃) thin films were coated on glass substrates using spray pyrolysis technique. 0.05 M ammonium heptamolybdate tetrahydrate was used as precursor and deionized water as solvent. The effects of carrier gas pressure, during the spraying of the solution, on the structural, optical, morphological and gas sensing properties of thin films were studied. X-ray diffraction (XRD) pattern analysis showed preferred growth at (020) peak direction and the formation of alpha phase of molybdenum oxide. The most intensive peaks were observed in the XRD pattern of the sample prepared under the carrier gas pressure of 2 bar, which indicates better crystallization of the sample. In addition, Raman spectrum of this sample confirmed the XRD results. UV-Vis spectroscopy results showed that the sample prepared under the carrier gas pressure of 1.8 bar has the highest optical absorption and the lowest band gap (~ 3.48 eV). Scanning electron microscope (SEM) images showed the layer structure of samples. Moreover, gas sensor devices based on the prepared samples at different carrier gas pressures, were fabricated and their sensing performances were investigated. Results showed that, the work temperature (i.e. the lowest temperature with the highest gas response at the specified ethanol vapor concentration of 200 ppm) was 200 ºC and belongs to the sample prepared under the carrier gas pressure of 1.8 bar. Also, studying the effect of ethanol vapor concentration extent for this sample showed the increasing of sensitivity percent from 1.42 to 15.62 % for 100 to 1000 ppm ethanol vapor, respectively.

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The Damanghor gold mineralization occurrence is located in north of Bardaskan, Khorasan Razavi Province, and Taknar zone.The geology of the area consists of Precambrian green sericite schist and metarhyolite, intruded by diabase. Mineralization in this area is in vein form with N50E stribe and 70NW dip and hosted by schist and metarhyolite with 300 meters length and 2 to 35 meters width. Disseminated and veinlet mineralization includes primary minerals of pyrite and chalcopyrite and secondary minerals such as covelit, malachite, azureite, hematite, goethite and limonite with quartz, sericite, and lesser clay minerals. Silicic-sericitic alteration is the most important alteration zone associated with mineralization. Based on rock samples taken from explorative trenches, gold anomalies range from 0.3 to 12.5 ppm, silver up to 30 ppm, copper up to 860 ppm, and zinc about 9252 ppm.Based on the evidence of host rock, the type and extent of alteration, structural control, shape and type of mineralization and primary minerals and geochemical anomalies, the occurrence of Damanghor gold mineralization is epithermal  with intermediate sulfidation state that is related to hydrothremal derived from Cenozoic magmatic activities.

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This study have been developed BiFeO₃/reduced graphene oxide (BFO/RGO) nanocomposites by introduction of RGO in the structure of BFO nanoparticles in a short term ultrasonic treatment. The X-ray diffraction pattern and Fourier-transform infrared spectroscopy analysis reveal that the BFO/RGO composites were successfully synthesized. UV-visible absorption show that the introduction of RGO can effectively reduce the recombination of photo-generated electron and hole pairs and the lower band gap energies were also identified for BFO/RGO composites as compared to 1.97 eV for BFO. The photocatalytic performance of BFO/RGO nanocomposites is stable and exhibit considerably higher photocatalytic ability over the pristine BFO for the degradation of methyl orange solution under visible light irradiation. The possible mechanism behind the superior photocatalytic performance of BFO/RGO nanocomposite has been critically discussed.

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In this research, Zn_0.97Cu_0.03O nanoparticles are prepared by sol-gel method using various stabilizers (Mono, Di, and Tri-ethanolamine). The effect of stabilizers on the structural, morphological and optical properties of the nanoparticles were investigated. Study of X-ray diffraction pattern shows the hexagonal wurtzite structure of samples. The crystallite size, strain, stress, and deformation energy of the lattice were determined by modified Williamson-Hall relations. The results showed the sample prepared with monoethanolamine has the lowest crystallite size, lattice parameter and strain. FESEM images revealed a decrease in nanoparticle accumulation with increasing amine group. By the change of mono to tri-ethanolamine in the primary sol, the red shift was observed at the near band edge emission of Pl spectra which consistent with decrease of optical band gap from 3.16 eV to 3.11 eV deduced from strain enhancement.

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In this work, the first ZnO/CuO nanocomposites were synthesized by chemical vapour deposition (CVD), thermal evaporation (PVD) and sputtering on silicon substrates (Si). Then, the structural, optical and electrical properties of the samples were investigated. Examination of the X-ray diffraction patterns confirmed the mixed-phase formation of hexagonal zinc oxide (ZnO) and monoclinic copper oxide (CuO) phases, resulting in the formation of ZnO/CuO composite in all methods. The plan view images obtained from FESEM analysis showed that the morphology of the samples prepared by the CVD method differs from other samples and is as nanowires with an average radius of about 400 nm. Examining the samples' optical properties showed that their bandgap is in the range of 2.05 eV-2.18 eV, which is larger than the bandgap of copper oxide (1.2 eV) and smaller than zinc oxide (3.3 eV). The composite synthesized by the CVD method has the lowest reflectance, and the sample prepared by the PVD method has the highest reflectance in the visible and near-infrared ranges. Examination of the room temperature photoluminescence (PL) spectrum of the sample prepared by PVD showed that these samples have emission peaks with significant intensities in the ultraviolet and visible ranges. The samples' electrical properties showed that the ZnO/CuO composite synthesized by sputtering and CVD had the lowest and highest electrical resistance, respectively. The samples' optical response study showed that the sputtering method's nanocomposites have the highest response. This study showed that, in general, the structural, optical and electrical properties and morphology of synthesized ZnO/CuO composites are significantly affected by their synthesis method.

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In this research, the Dysprosium stannate nanostructured compound (Dy₂Sn₂O₇) is prepared as an important spin ice compound. In the synthesis of this compound, from a solution of 0.1 mol of Tin (IV) chloride pentahydrate (SnCl₄; 5H₂O) with the addition of Dysprosium (Dy (NO₃)₃.xH2O) nitrate with molar ratios equal to [Dy / Sn] = 0.1, 0.3, 0.5, 0.7 and 0.1 were used to prepare Dysprosium stannate nanocrystals (Dy₂Sn₂O₇) by hydrothermal method. The effect of Dysprosium (Dy) with different percentages on the formation of Dysprosium stannate composition by annealing at T= 1100 ° C in normal environment was investigated. The structural and optical properties of the formed compound were investigated. The results of X-ray diffraction (XRD) patterns of the sample annealed at T=1100 ° C showed the formation of nanocrystals in the pyrochlore structure of the Dysprosium stannate with [Dy / Sn] =1. The results of visible-ultraviolet (UV-Vis) spectroscopy showed that the energy gap increases with increasing Dysprosium additive. Field Emission Scanning Microscope (FE-SEM) images confirm the formation of Dysprosium stannatenanocrystals with pyrochlore structure.