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The findings of comprehensive studies on morphology, physico-chemical properties of sewage sludge, as well as practicalities of its application have been introduced. The sewage sludge used for the research came from the purification facilities of Volzhsky after the preliminary treated by the enzymatic-cavitation method. The morphology and structure of the processed sewage sludge have been determined by scanning electron microscope investigation and X-ray phase analysis. The chemical composition of the processed wastewater sludge have been and tested as an organic fertilizer in the cultivation of the false saffron.

For the first time, yttrium-iron-garnet films with a thickness of 0.5 µm on nonoriented single-crystal lithium niobate LiNbO3 substrates are obtained by the ion-beam sputtering–deposition method. The surface profile and composition of the samples obtained are studied by atomic force microscopy, scanning electron microscopy, and X-ray phase analysis. Based on the data of optical and magnetic measurements, as well as the results of studies of spin-wave propagation in ferrite-garnet films on LiNbO3 substrates, we conclude that the reproducible formation of high-quality structures by nonepitaxial methods is possible for obtaining optically transparent straintronic materials, as well as the development of microwave electronic materials.

The interaction of Ra(NO3)2 and RaCO3 with metallic Fe, Ni, Cr, Ti has been studied. Experimental samples were fabricated by deposition of water-alcohol suspensions of radium salts onto substrates made of the corresponding metals, followed by evaporation and calcination for 7–14 h at a temperature of 800°C. According to the results of an X-ray phase analysis, mixed oxides of composition RaMOx, where M = Fe, Cr, Ti, Ni, in joint calcination of Ra(NO3)2 and RaCO3 with Fe, Ni, Cr, Ti metals.

We successfully refined a cheap commercial boron powder by means of high-energy ultra-sonication and utilized it in synthesis of bulk MgB2. Rietveld phase analysis of X-ray diffraction pattern revealed completely formed MgB2 with a low amount of MgO. MgB2 bulk prepared of boron ultra-sonicated in ethanol for 15 min showed self-field Jc of around 300 kA/cm2 at 20 K without any compromise in Tc (~39 K). Pinning analysis based on Dew-Hughes expression showed major pinning contribution from grain-boundary pinning (~95.5%), along with a slight contribution from point pinning (4.5%). The microstructure study detected a system of large MgB2 grains (hundreds nm large) and 10–20 nm sized particles, possibly Mg-B-O, formed at MgB2 grain boundaries.

Solid-phase equilibria in the Tm–Te system and the thermodynamic properties of thulium tellurides are studied via electromotive force (EMF) method and X-ray phase analysis. Experimental data show that compounds TmTe, Tm2Te3, and TmTe3 form in the system. The partial thermodynamic functions of TmTe and Tm in alloys are found for the first time from EMF measurements in concentration cells, relative to TmTe and Tm electrodes at 300–450 K, from which standard thermodynamic functions of formation and standard entropies of intermediate compounds are calculated.

Yttrium-aluminum garnet (YAG) nanoparticles are synthesized by the coprecipitation of yttrium and aluminum hydroxides in a microreactor with freely impinging jets, followed by the thermal treatment of the coprecipitation products. According to the results of X-ray phase analysis, the coprecipitated hydroxides are X-ray amorphous. Analysis of the product of the thermal treatment of hydroxides at 1000°C for 10 min indicates the formation of Y3Al5O12 crystals. The method developed by us makes it possible to carry out the synthesis quickly, ensures low energy consumption, does not require laborious operations, and is technologically advanced and easily scalable.

The aim of this study is to produce highly dense Si3N4 based composites with good mechanical properties and bioactivity. Si3N4 ceramics without using sintering aids, Si3N4-HA and Si3N4-HA-GNP based composites have been produced by spark plasma sintering (SPS) at temperatures of 1525–1550°C. The effect of reinforcement type and content on the densification behavior, phase analysis, microstructural development, mechanical properties, and in-vitro bioactivity behavior of Si3N4 were systematically investigated. Monolithic Si3N4 that contains a high amount of β-Si3N4 phase (~87 wt%) was produced by nearly full densification (~99%). Hydroxyapatite (HA) was used as a starting powder during the preparation of binary and triple composites to provide bioactivity to Si3N4, and after sintering, HA transformed into tricalcium phosphate (β-TCP and α-TCP) polymorphs. The incorporation of GNPs had a positive effect on the stability of β-TCP phases at higher sintering temperatures. The improvement in indentation fracture toughness of the samples with GNP reinforcement was mainly attributable to pull-out and crack deflection mechanisms. In-vitro bioactivity of GNP added composites enhanced with increasing α-TCP content. More calcium phosphate-based particle formation was observed in Si3N4-HA-GNP composites compared to the Si3N4-HA.

We report a refractive index tip fiber optic sensor based on a modal interferometer coated with a thin copper film. This device can be used for solute concentration in aqueous mixture measurement. The copper film increases the device reflectivity and, as a result, increases the multimodal interference pattern visibility. To validate the sensor device, different water-glycerol weight concentrations were used in the range from 0 to 45 Glycerol %. The recorded spectral responses show a redshifting, and a sensitivity of 19 pm / (Glycerol % by weight) from 0 to 18 % and 4.7 pm / (Glycerol % by weight) from 18 to 45 % was achieved. Besides, using a phase analysis we calculated a sensitivity of -15 rad/RIU.

We investigate the melting ranges of the base Zr–Si mixture (eutectic composition) depending on the content of the heterophase powder component in the ZrB2–ZrSi2–MoSi2 and the HfB2–HfSi2–MoSi2 systems in the amount of 30–90 wt % obtained by self-propagating high-temperature synthesis (SHS). The range of the melting point of the Zr–Si mixture was 1420–1440°C; addition of the ZrB2–ZrSi2–MoSi2 SHS powders resulted in an increase of the melting onset temperature Tm0 to 1460–1560°C and in the complete melting temperature Tmelt to 1480–1670°C. Addition of the HfB2–HfSi2–MoSi2 powders influenced only slightly the Tm0 value (1390–1430°C), but resulted in the increase in Tmelt to 1510–1550°C. The X-ray phase analysis shows that the remelted samples contain the following phases: ZrB2/HfB2, ZrSi2/HfSi2, MoSi2, and Si; here, the number of phases was directly proportional to the SHS powder content in the Zr–Si mixture. The ingots are characterized by a homogeneous structure consisting of the silicon matrix and ZrSi2/HfSi2 and MoSi2 grains, with inclusions of ZrB2/HfB2.

Self-propagating High-temperature Synthesis (SHS) process is used to prepare Aluminium dodecaboride (AlB12). The phase analysis results of preparing AlB12 with Al and B2O3 as raw materials show that under air and argon conditions, the self-propagating and acid-washed self-propagating powders all have α-Al2O3 impurities when Mg, Al and B2O3 are used as raw materials. The phase analysis results of the preparation of AlB12 show that under argon conditions, the self-propagating and acid-washed, self-propagating powder has un-removable MgAl2O4 impurities, and the root cause of the low purity of AlB12 prepared by the self-propagating method is the presence of un-removable impurities.

This paper reports a study into the phase composition and microstructure of tungsten ore concentrate after carbon-thermal reduction at different O:C ratios in the charge. This is required for determining those indicators that reduce tungsten loss through the sublimation of oxide compounds when processing ore concentrates, as well as when using reduced tungsten-containing doping additives. The study results have established that the reduced tungsten concentrate at the O:C ratio in the charge within the interval of 1.33‒2.30 contained the phases of W, W2C C, C, WO2. The microstructure demonstrated a spongy and disordered character. Together with W, the Mo, Si, Ca, Al impurities were present in the reduced products. The main elements identified at the sites studied had the following limiting content,% by weight: O – 5.01–17.32; C – 0.84–4.23; W – 61.21–86.78; Mo – 1.57–7.51; Si – 2.07–9.06; Ca – 1.34–11.30; Al – 0.27–0.40. The micro-inclusions at the examined surface areas acquired different complex shapes. There were traces of the process of caking between the particles. The analysis of the resulting data has shown that the most preferred ratio of O:C in the charge was 1.65. In this case, there is no lack of carbon and there is a predominance of W in the phase composition with a relatively little manifestation of the W2C phases, carbon, as well as the residual part of WO2. The post-reduction of the oxide component would occur during the doping process. The sponge structure contributes to a higher dissolution rate compared to standard tungsten ferroalloys. Lack of compounds with a relatively high propensity for sublimation does not require any special conditions to prevent the loss of tungsten in the gas phase, which increases the degree of assimilation of the target element

In the present work, CZTSe (Cu2ZnSnSe4) films were deposited by Thermal evaporation technique. The as deposited films were annealed at 450 °C for 10 min. To incorporate Sulfur in the CZTSe film and to replace some of the Se by S, the films (as deposited and annealed) were treated with Thiourea solution (1 Molar). Further the films were annealed at 450 °C for 10 min after the thiourea treatment. Finally the films were characterized for phase analysis using XRD and Raman. The composition analysis was done using EDXRF. The band gap of the film varies according to the S/Se ratio. Compositional analysis as obtained from ED-XRF, shows the required ratio of Cu/(Zn + Sn) 1 for all the films. The conductivity and mobility of the films changes with variation in sulfur and selenium ratio. The obtained electrical and optical properties of CZTSe absorber layer after thiourea treatment are suitable for device application.

The possibility of high electrical conductivity of dry sliding electrical contact against a molybdenum counterface was studied. It was found that metals W and Cu were not able to form a sliding electrical contact with high wear resistance at current density higher 100 A/cm2. The characteristics of the contacts of iron containing metals were slightly better than the contact characteristics of nonferrous metals owing to weaker adhesion. Using X-ray phase analysis, the absence of oxides in the sliding zone of nonferrous metals was shown. This led to their strong wear and low electrical conductivity of contact. In the contact zone of iron-containing samples, the formation of FeO was observed, which made it possible to reduce wear. This means that high electrical conductivity is unattainable in sliding with current collection against molybdenum.

Copper powder spraying is under study: the PMS-1 feedstock copper, the copper that is mechanically milled in a high-energy planetary mill, and the copper that is also spheroidized in a plasma jet. High-density copper coatings are obtained using a CCDS2000 detonation facility. The Vickers microhardness of coatings $$H_{{\mathrm V}_{0.1}}$$ , obtained from feedstock and mechanically milled copper powders, increases from 110 to 160 and from 150 to 185, respectively, and the microhardness of coatings from the spheroidized powder is $$H_{{\mathrm V}_{0.1}}=165$$ . An X-ray phase analysis is carried out, and the resulting data indicate that, during the spraying, the copper oxide is partially reduced.

We synthesized an intermetallic compound Gd2Co7 with Ce2Ni7- and the Er2Co7-type structures. Gd2Co7 with a Ce2Ni7-type structure was stable at 1523 K. The refined lattice parameters were a = 0.5026(1) nm and c = 2.4266(6) nm. The pressure-composition (P–C) isotherm of Ce2Ni7-type Gd2Co7 indicated that reversible hydrogen capacity reached 0.61 H/M (0.76 mass%), and two plateaus were observed in the absorption-desorption process. The crystal structures of both Gd2Co7H2.5 and Gd2Co7H5.5 were determined to be Ce2Ni7-type by X-ray diffraction. Gd2Co7 with Er2Co7-type structure is stable at temperatures below 1473 K. The refined lattice parameters were a = 0.5029(1) nm and c = 3.6403(9) nm. The determined crystal structure of Gd2Co7H2.3 and Gd2Co7H5.4 was Er2Co7-type. The P–C isotherm of Er2Co7-type Gd2Co7 was similar to that of Ce2Ni7-type Gd2Co7. In this study, the P–C isotherms of a polymorphic binary alloy with Ce2Ni7-type and Er2Co7-type structures were obtained for the first time.

Here, the crystal structure, phase analysis, site occupancy, and luminescence properties of NCMP:Eu2+,Tb3+,Mn2+ have been studied for the first time. Under 335 nm ultraviolet excitation, the NCMP:E...

The traditional process of alumina production by acid method was to neutralize the aluminum chloride solution obtained by acid leaching for preparing aluminum hydroxide, and then calcined to produce alumina. This process not only had many processes, but also had high energy consumption. In this paper, the properties of alumina prepared by pyrolysis of aluminum chloride solution were studied by chemical composition analysis, XRD and SEM. Thermodynamics of the pyrolysis process was analyzed. The effects of temperature and time on the pyrolysis properties of aluminum chloride solution were investigated. The results showed that it would be completely feasible according to thermodynamic calculation of the pyrolysis reactions of aluminum chloride solution. Meanwhile with the increasing of temperature and pyrolysis time, the residual chlorine content decreased gradually, and the particle size of the product decreased and tended to be uniform. The prolongation of pyrolysis time promoted the pyrolysis process of aluminum chloride solution and contributed to the formation of Al2O3 phase.

Monoclinic zirconium dioxide compositions of formula ZrO2–Al2TiO5 containing 0, 2, and 3.5% Al2TiO5 are studied. The aim of the research is to study the effect of aluminum titanate additives on the parameters of the monoclinic zirconium dioxide crystal lattice and sintering of the resulting product. The formation of a solid solution of aluminum titanate in monoclinic zirconium dioxide is confirmed using SEM and x-ray phase analysis. Sintered products are made from monoclinic zirconium dioxide with aluminum titanate additives as a proof of concept.

Improvement of the physical and mechanical properties of hard alloys based on WC – Co widely used in manufacturing of structural and tool products nowadays results from the use of novel technologies providing formation of a homogeneous high-density structures. Slight deviations of the carbon content from the equilibrium state lead to the formation of brittle η-phases (in particular, Co3W3C) and, accordingly, to deterioration of the mechanical properties of the product. We present the results of studying the homogeneity of the phase composition of the samples of hard alloys WC + 10% Co, obtained using advanced technologies of plasma-chemical synthesis and spark plasma sintering (SPS). The layer-by-layer X-ray phase analysis revealed the heterogeneity of the phase composition in depth: the brittle η-phase (Co3W3C) appears at a depth of ≥100 μm and reaches a constant value of 18 ± 1 wt.% at >200 μm, which indirectly confirms the hypothesis of carbon diffusion from graphite punches contacting with the surface of sintered samples and makes it possible to expand the range of parameters affecting the process of spark plasma sintering.

OAbstract. One of the approaches that has been done to produce a better performance of an intermediate temperature solid oxide fuel cell (IT-SOFC) is by varying the synthesis methods. This paper focused on the proton conducting electrolyte in particularly barium cerate and barium zirconate system namely BaCe0.9Y0.1O3-δ (BCY) and BaZr0.9Y0.1O3-δ (BZY). Supercritical ethanol processing technique is one of the alternative synthesis routes that able to produce ceramics powder at lower calcination temperature. The samples were synthesized in High-Pressure-High-Temperature (HP-HT) Batch Wise reactor system using ethanol as reaction medium. XRD was used to study the structure of both samples and all the data were refined using Rietveld refinement method by X’pert Highscore software. VESTA software is used to observe the crystal structure for both BCY and BZY samples. Both BCY and BZY have 98.16% and 96.55% purity after being calcined at 700°C and 1100°C, respectively. This study showed that BCY has orthorhombic structure with lattice parameter a=8.76Å, b=6.24Å and c=6.21Å and BZY exhibited cubic structure with a=b=c, and a=4.194Å. It was observed that BCY synthesized by supercritical fluid (SCF) method at reduced calcination temperature exhibited an acceptable value of lattice paramter as compared to other method that used higher processing temperature.

Ni-coated mixed powders were synthesized via chemical co-precipitation and hydrogen thermal reduction. Ti(C,N)-based cermets were further fabricated using as-prepared Ni-coated mixed powders successfully. Phase analysis, microstructure characterization, and properties of synthesized powders as well as the as-sintered cermets were investigated using a variety of techniques, including XRD, SEM, EDS. The results exhibited that XRD patterns of present experimental cermets only showed two diffraction peaks that correspond to Ti(C,N) hard phase and nickel binder phase. Also, microstructures of as-sintered cermets were more uniform and finer than those of traditional cermets with the same nominal composition. Meanwhile, present cermets prepared using chemical-coated method had excellent mechanical properties.

The functional refractories used in the continuous casting process of steel are mostly made up of alumina (Al2O3) - carbon (C) system. Graphite is used as the main carbon source because of the properties it offered. Generally, these refractories contain about 30% residual carbon after coking. But the use of high carbon content leads to several disadvantages like carbon pickup by steel, high heat loss and generation of higher extent of COx gases, etc. Hence, the development of low carbon Al2O3-C refractories without conceding any beneficial properties is the challenge to the refractory technologists. Such a challenge is intended in current study with the use of nanocarbon as a complete alternative for graphite. The variation in physical, mechanical and thermo-mechanical properties with variation in amount of nanocarbon in the composition is studied. Phase analysis and microstructural developments are also evaluated along with the oxidation resistance at different temperatures. Because of its high reactivity, nanocarbon helps to form in-situ ceramic phases at much lower temperatures thereby enhances strength and other properties. But the increase in amount of nanocarbon above 2% found to deteriorate the properties.

This paper investigates the potential of a laboratory test for the screening of aggregate reactivity to alkali–silica reaction (ASR) through phase analysis of the phases developed in ground aggregate paste (GAP) specimens subjected to accelerated ageing. GAPs were prepared using two aggregates categorised as non-reactive and potentially reactive by standard expansion test methods and were aged at 40, 60 and 80 °C in 1 M NaOH solution over periods up to 84 days. Phase development was monitored using TG, XRD and FTIR, and the reactivity was correlated with quartz and calcium hydroxide consumption. The data demonstrate that this test has the potential to be developed as a screening test, based on the correlation of phase consumption with Australian standard expansion test reactivity categorisation.

The possibility of high electrical conductivity of dry sliding electrical contact against molybdenum counterbody was studied. It was found that metals W and Cu were not able to form a sliding electrical contact with high wear resistance at current density higher 100 A/cm2 . The characteristics of the contacts of iron containing metals were slightly better than the contact characteristics of non-ferrous metals due to weaker adhesion. Using X-ray phase analysis, it was shown the absence of oxides in the sliding zone of non-ferrous metals. This led to their strong wear and contact’s low electrical conductivity. In the contact zone of iron containing samples the formation of FeO was observed that made it possible to reduce wear. This means that high electrical conductivity is unattainable in sliding with current collection against molybdenum.

In this research, alumina sol has been synthesized via an inorganic route using inexpensive starting materials including aluminum nitride, deionized water, ammonia, and nitric acid. A clear, homogenous and stable sol was achieved which converted to a soft gel at 60 °C. The physical and microstructural properties of synthesized sol such as pH, particle size, density, solid content, phase analysis, nature of bounds, and thermal behavior were investigated. The pH of the prepared sol was in the range of 3–4, and the solid content was measured by about 6% at the temperature of 1000 °C. Utilizing the SEM micrographs, the average particle size of the dried and calcined sol at 110 °C and 1000 °C were measured less than 20 nm and 40 nm, respectively. XRD patterns of calcined sol at 200, 600, 1200, and 1400 °C revealed the formation of β-alumina (boehmite), γ-alumina, and α-alumina, respectively. Above the temperature of 1200 °C clear and sharp peaks of α-alumina appeared. Also, TG-DSC patterns confirmed the formation of β phase at 200 °C, boehmite into γ transformation at approximately 450 °C, and the alter of γ into α phase at temperatures above 1000 °C.

The use of phase analysis techniques to assess left ventricular mechanical dyssynchrony (LVMD) has been well documented. However, artifacts have reduced the accuracy of the assessment due to soft tissue attenuation, so little information is available about the effects of obesity on LVMD. The aim of this study was to evaluate LVMD in patients with simple obesity by SPECT with a new cadmium-zinc telluride (CZT) detector and to explore the effects of obesity on left ventricular wall motion. We retrospectively analyzed 95 patients with myocardial perfusion imaging (MPI) images without perfusion defects, of which 55 were diagnosed with simple obesity (BMI 30), and 40 non-obese patients (BMI 25) matched for age and sex were used as controls. The five-point method was used to analyze the MPI images of the two groups, and the complete cardiac function parameters including phase bandwidth (PBW) and phase standard deviation (PSD) were obtained. Although the PBW values of the two groups were within the normal range (cut-off value 90°), the PBW (35.4 ± 28 vs 24.9 ± 7.5, P .001; 36.6 ± 18.4 vs 28.7 ± 9.1, P = 0.01) and PSD (8.7 ± 7.6 vs 5.9 ± 2, P = 0.02; 9.2 ± 4.9 vs 7.1 ± 2.7, P = 0.01) of the obese group were larger than the control group under both stressing and resting, and the difference was statistically significant. CZT-SPECT can effectively assess LVMD in obese patients, and they are more likely to develop LVMD, which may be related to their left ventricular volume.

The quantitative study of polymorphism in fats iscomplicated due to their complex composition and consequentintricate crystallization behavior. We aimed to illustrate howquantitative phase analysis can be performed in crystallizingcomplex fats. The advantages of our proposed method are thatdetailed structural information or internal standards are not neededand that it can be applied even to wide-angle X-ray diffractionpatterns with a high noncrystalline (liquid fat) contribution andoverlapping peaks. Diffraction patterns of palm oil and anhydrousmilk fat during crystallization were decomposed by fitting a modelbased on Pearson type VII functions. From the decomposed patterns, the contribution of each phase was quantified as a function of time. Each contribution to the pattern was then converted to its mass fraction using response factors derived from the corresponding solid fat content, which was measured using low-resolution nuclear magnetic resonance (NMR). This approach allowed us to quantify the evolution of liquid and polymorphic phases during the early crystallization of complex fats and, for the first time, to quantify coexisting α, β′, and β phases. This method is flexible enough for fats with diverse triacylglycerol profiles yet detailed enough to quantify phase transitions in a system as complex as milk fat

The aim To assess the diagnostic performance of dual-energy computed tomography (DECT) in the evaluation of the composition of urinary stones "in vivo". Materials and methods A total of 91 patients aged from 20 to 70 years old (mean 42.7) with urinary stone disease were examined at Sechenov University, including 68 men (75%) and 23 women (25%). Prior to surgery, all patients underwent DECT (Canon, Japan) in order to predict the chemical composition of urinary stones in vivo. Extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS) was performed in 53 (58.2%), 18 (19.7%) and 20 (22.1%) patients, respectively. Postoperatively, all stones or stone fragments (n=91; 100%) were examined using a comprehensive physical and chemical analysis (X-ray phase analysis, electron microscopy, infrared spectroscopy). Results In 6 patients (6.6%) staghorn stones were diagnosed, while in 15 (16.5%), 17 (18.7%), 22 (24.2%) and 31 (34.1%) stones were located in ureteropelvic junction, pelvis and ureter, respectively, including 24 patients with lower ureteric stones (26.4%). Prediction of the stone composition in vivo was carried out on the basis of the one indicator, the dual energy ratio (DER). The threshold values of DER for different types of stones were taken from the literature. All stones were divided into 4 groups according to the DECT results: vevellite stones (n=40, 43.9%), Ca-containing stones without vevellite (n=34, 37.3%), uric acid stones (n=10, 10.9%) and struvite stones (n=7, 7.9%). Thus, when comparing the results of DECT and physical and chemical analysis, in the first group four stones were incorrectly assigned by DECT to the group of Ca-containing stones without vevellite and three stones were incorrectly assigned to the group of struvite stones; in the second group four stones were incorrectly assigned to the group of vevellite stones; in the third group one stone was incorrectly assigned to the group of struvite stones; in the fourth group one stone was incorrectly assigned to the group of vevellite stones and one stone in the group of uric acid stones. In order to increase the diagnostic efficiency of DECT, we performed a comprehensive analysis of five specific DECT indicators (stone density at 135 kV, Z eff of the stone, DER, DEI, DED) using discriminant analysis. Thus, the sensitivity, specificity and overall accuracy of DECT with the use of just one indicator (DER) were 83.3%, 89.8%, 86.8% for vevellite, 88.2%, 92.9%, 91.2% for Ca-containing stones without vevellite, 90%, 98.8%, 97.8% for uric acid stones and 60%, 95.3%, 93.4% for struvite stones, respectively. When using discriminant analysis with five specific DECT indicators, higher values of sensitivity, specificity and overall accuracy were seen: 95.2%, 89.8%, 92.3% for a vevellite, 85,3%, 96,4%, 92,3% for Ca-containing stones without a vevellite and 100%, 100% and 100% for both uric acid and struvite stones, respectively. Conclusions Dual-energy computed tomography is a highly informative method which allows to perform preoperatively the reliable assessment of the chemical composition. DECT in patients with urinary stone disease allows to optimize the treatment strategy and carry out preventive measures on individual basis, taking into account the stone type.

Investigation of dynamic changes in friction behavior of ultrananocrystalline diamond (UNCD) films is a complex mainly because of the rapid change in chemical composition at the sliding interfaces. To address this issue, for the first time, we report chemical phase analysis of transferfilm using the depth-resolved X-ray photoelectron spectroscopy (XPS) technique. The friction coefficient of the UNCD films was high during the initial run-in regime, but it gradually decreased to an ultralow value after longer sliding cycles at the ambient atmospheric tribo-condition. Depth-resolved XPS analysis showed a higher sp3/sp2 carbon ratio during the initial run-in regime. This ratio decreased with increasing sliding cycles and consequently the friction coefficient decreased. However, a higher value of the friction coefficient throughout the run-in regime persisted at the high-vacuum tribo-condition. In this case, the sp3/sp2 carbon ratio inside the transferfilm was quite high and no considerable changes were observed in the depth-resolved XPS analysis. This investigation confirmed that the dynamic friction behavior in UNCD films was manipulated by the sp3/sp2 carbon ratio inside the transferfilm which showed tribo-atmospheric dependence.

Aluminum alloys based on the Al-Ge-Si system with a germanium content of up to 40 wt.%, promising for the brazing of aluminum alloy AA6082 with the stainless steel AISI 304, were studied. The temperature characteristics and microstructural and mechanical properties of the filler alloys were systematically investigated. Differential scanning calorimetry showed that with an increase in the germanium content from 28.0 to 40.0 wt.%, the liquidus temperature of the filler alloys decreased from 514.8 to 474.3 °C. X-ray diffraction analysis and electron microscopy data showed that the foil of the filler alloys reveals a homogeneous structure. The ingots of the alloys contain two eutectics, the first of which consists of a solid solution of (Al, Ge) with a solid solution of (Ge, Si), and the second consists of a solid solution of (Al, Ge) with a solid solution based on (Ge). When the content of germanium increases from 28.0 to 40.0 wt.%, a separation of the faceted solid solution particles (Ge, Si) and an increase in their number could be observed. Nanohardness measurements showed that the (Ge, Si) and (Ge) solid solutions had similar nanohardness, with values of 11.6 and 10.2 GPa, respectively. Simultaneously, the Al solid solution and the intermetallic Al7Ge2Fe phase exhibited significantly lower nanohardness values of 0.7 and 6.7 GPa, respectively. Brinell hardness measurements showed that the ingots of the filler alloys were sufficiently ductile and had a hardness comparable to that of AA6082, which is used for brazing with AISI 304 stainless steel. The obtained results for the studied ingots and the rapidly quenched foils can be used to predict the forming structure of the seam after brazing and adjusted for diffusion processes occurring between the brazed materials and the studied filler alloys.

The roasting of sulfide ores and concentrates is one of the most important steps in pyrometallurgical metal production from primary raw materials, due to the necessity of excess sulfur removal, present in the virgin material. Pentlandite is one of the main sources for nickel pyrometallurgical production. The knowledge of its reaction mechanism, products distribution during oxidation and reaction kinetics is important for optimizing the production process. Raw pentlandite-bearing ore from the Levack mine (Ontario, Canada) was subjected to oxidative roasting in the air atmosphere. A chemical analysis of the initial sample was conducted according to EDXRF (Energy-Dispersive X-ray Fluorescence) and AAS (Atomic Adsorption Spectrometry) results. The characterization of the initial sample and oxidation products was conducted by an XRD (X-ray Diffraction) and SEM/EDS (Scanning Electron Microscopy with Energy Dispersive Spectrometry) analysis. Thermodynamic calculations, a phase analysis and construction of Kellogg diagrams for Ni-S-O and Fe-S-O systems at 298 K, 773 K, 923 K and 1073 K were used for proposing the theoretical reaction mechanism. A thermal analysis (TG/DTA—Thermogravimetric and Differential Thermal Analyses) was conducted in temperature range 298–1273 K, under a heating rate of 15° min−1. A kinetic analysis was conducted according to the non-isothermal method of Daniels and Borchardt, under a heating rate of 15° min−1. Calculated activation energies of 113 kJ mol−1, 146 kJ mol−1 and 356 kJ mol−1 for three oxidation stages imply that in every examined stage of the oxidation process, temperature is a dominant factor determining the reaction rate.

Materials exhibiting a giant magnetocaloric effect (GMCE) need to be finely tuned with respect to their magnetic and structural properties, specifically their respective transition temperatures. Co-Mn-Ge and Co-Mn-Ge-Si thin-film materials libraries (MLs) were fabricated and characterized to determine the composition range in which the CoMnGe phase is stable and analyze selected single-phase measurement regions. Phase analysis was performed on these MLs and refined in regard to the CoMnGe single-phase region by synchrotron diffraction experiments. A comparison of the MLs revealed that the CoMnGe (HT) single-phase region gets smaller with the addition of Si and exists for 26.5 at. %Co29.5 at. %, 34 at. %Mn37 at. %, Ge ∼ 35 at. %, and Si ∼ 1.5 at. % in the quaternary ML. The investigation of magnetic and structural transition properties in this region revealed hard-magnetic behavior with Curie temperatures (

First in the Au-Te-Se-S system (where Te ≥ Se + S) quadruple chalcogenides were obtained by dry synthesis: AuX (AuTe 0,7 Se 0,2 S 0,1 ), Au 3 X 10 (Au 3 Te 6 Se 3 S, Au 3 Te 6 Se 2,5 S 1,5 ) и AuX 2 (AuTe 1,8 Se 0,2 , AuTe 1,8 Se 0,1 S 0,1 ). According to the results of X-ray phase analysis, the synthetic phases of the composition AuTe 1,8 (Se,S) 0,2 correspond to the calaverite (AuTe 2 ). The unidentified peaks on the diffractograms belong to the new gold chalcogenides AuTe 0,7 Se 0,2 S 0,1 and Au 3 Te 6 (Se,S) 4 . Obviously, they are synthetic analogues of compounds previously unknown in nature, found on the Gatching occurence of the Maleteuyamsky ore field (Central Kamchatka volcanic belt). The compositions of natural phases cover the intervals: 1) Au 0,99-1,00 Te 0,70-0,71 Se 0,25-0,27 S 0,03-0,06 ; 2) Au 2,91-3,08 Te 5,85-6,06 Se 1,57-3,66 S 2,63-0,44 . Raman spectra of synthetic and natural gold chalcogenides with a similar composition have identical character.

—By differential thermal analysis and X-ray phase analysis, the reducing properties of special-purpose coke (Reksil) used in the electrothermal production of silicon are compared with those of other solid reducing agents. On the basis of the derivatograms, the kinetic characteristics of the redox processes are calculated.

Separation of aluminum from fine granules of black dross, which is a waste by-product in secondary aluminum production, was investigated. The separation was performed by a multi-stage electrostatic separation method. There are three stages to complete the separation, including preliminary separation, pulse charging enhancement and secondary concentration. Chemical and mineralogical compositions of collection products were analyzed and determined by X-ray diffraction (XRD) and X-ray Fluorescence (XRF). After multistage electrostatic separation, the Al2O3 content of the collection products increases from 50.74% to 69.77%. The mineralogical phase analysis indicates that the final recovery of metallic aluminum phase increases from 8% to 37%, and the aluminum oxide phase increases from 20% to 26%. The research results show the multi-stage electrostatic separation method is effective for recovering of aluminum from fine granules of black dross, and upgrades the black dross to a recoverable material.

In the steel industry, ferromanganese is an important additive. During the production of ferromanganese the ore goes through prereduction and reduction. The prereduction step is very important, as the degree of reduction during ferromanganese is important. Although many investigations have been conducted on different manganese ores, the current study investigated different phases that formed during prereduction when South African ore was used. The ore was mixed with carbon in excess as the reducing agent, and no fluxes were added while CO gas was blown in the furnace. The temperature was varied from 1000°C to 1200°C with 100°C interval. For each temperature, the time varied from 30 min to 90 min with 30 min interval. The ore to carbon ratio was 4:1. After the experiments, the resulting products were subjected to chemical and phase analysis using XRD, XRF and SEM.

A possibility of obtaining bimetallic Pt-W particles in an autoclave at 190°C in an alkaline solution was shown. Structure of the obtained particles was studied by dynamic light scattering and X-ray phase analysis. A possible route for the reduction of platinum and tungsten in the selected conditions to the metallic state with ammonia in statu nascendi was proposed.

Manufacturing a specified polymorphic form of an active pharmaceutical ingredient (API) is of immense importance in the pharmaceutical industry. Crystal polymorphism and transformations among different forms of APIs are studied in detail during process development. While associated impurities in API are characterized in depth for their chemical structures and properties, solid state characteristics of impurities are usually overlooked, mainly because of their presence in low levels. Herein, we discuss a case of a process impurity, BrettPhos oxide (BPO), interfering with in-process phase analysis of an API. The impact of changing the workup procedure on the impurity purging and its effect on solid form analysis of the API is highlighted. Complexities encountered due to interplay between different solid forms of BPO and API are presented. Further, phase behavior of BPO in some common process relevant solvents is established.

The processes occurring in glass-ceramic solders of sapphire-niobium seals, used as current lead-ins in gas-discharge lamps with a discharge in alkali-metal vapor, were studied. The structural changes occurring in the glass-ceramic solder, based on the system of oxides CaO–Al2O3 and CaO–MgO–Al2O3, upon heating to 1600°C with niobium diffusing into the melt, are analyzed on the basis of x-ray phase analysis of the composition and a study of the microhardness.

The corrosive behavior of AISI 304 steel in solutions of sulfuric acid with additions of NaCl and Na2MoO4·2H2O was investigated by electrochemical measurements. The electrochemical conductivity of the obtained oxide coatings was studied by the method of impedance spectroscopy. Microphotographs of the structure of coatings obtained are shown. Special attention is given to X-ray phase analysis coatings formed in acid solutions.

Friction coefficients and wear resistance are determined, and the x-ray phase composition of experimental samples of obtained material on the basis of silicon and carbon is studied in this paper. Secondary products of the industry were used as initial powder to conduct spark plasma sintering. The composition of burden used for sintering, which was 75% of the mass of silicon and 25% of the mass of graphite (carbon basis), was determined by calculation. Studied samples were obtained by spark plasma sintering method. Based on the analysis of results of the phase composition of the samples obtained by spark plasma sintering method using secondary products of the industry as the initial components, the following conclusions can be made: - It was found that all samples obtained by the method of spark plasma sintering consist of the following phases: The phase of metallic silicon (cubic crystal lattice), the phase of graphite (hexagonal crystal lattice), the phase of silicon carbide with cubic and hexagonal lattice and have a low coefficient of friction; - It was determined that the mass fraction of the silicon carbide phase content is from 20 to 30% depending on the heating temperature; - It was found that the increase in the sintering temperature of the samples have a beneficial effect on the wear intensity of obtained ceramic material; - It was found that from the obtained samples of carbide silicon ceramics the wear resistance of the material increases and the friction coefficient and wear decrease due to an increase in the mass fraction of the carbide phase, that is, a more dense frame is formed. Based on the above, we can say that with an increase in the sintering temperature, the interaction of powder components forms a more stable frame of silicon carbide, which is proved by conducted phase analysis.

Non linear optical materials have been used for different technological application and Potassium Hydrogen Phthalate is one of the materials with better non linear optical properties. Hence in the present study we have grown KHP crystals doped with thiourea using slow evaporation technique. The phase analysis was done by Powder XRD and the incorporation of thiourea in the grown crystals was analyzed using FTIR. The thermal property of doped crystal is improved very much and the SHG efficiency of thiourea doped KHP crystal is better than that of the pure. The UV absorption spectrum of grown crystal shows that the thiourea doped crystals would be a better NLO material for SHG applications.

The problems of electroerosion phenomena in the diamond grinding zone under the action of additional energy in the form of electric discharges are considered. The erosion effects of electric discharges on the surface of Cu-Sn bonding of diamond grinding wheels are analyzed. Using the methods of X-ray structural and metallographic analysis, the influence of electrical discharges on the bonding is evaluated. Phase analysis indicates changes in the composition and properties of metal bonding with occurrence of new phases that differ from the original structure

In this study, we investigate a low-grade oxidized lead ore containing noble metal silver, with complex mineralogy. The sulfurization behaviors of different types of lead-silver minerals at different pH values were analyzed using the chemical phase analysis method. The interactions between different types of lead-silver minerals and different types of collectors were investigated. An effective laboratory process was developed, and closed-circuit tests were carried out at industrial sites. We found that the order of difficulty for sulfidizing various lead minerals and silver minerals was (PbFe6(OH)12SO4)4 &lt, PbCO3 &lt, PbSO4 &lt, Pb5(P/As/VO4)3Cl, Ag2AsS2 &lt, AgCl &lt, natural-Ag. Aerophine 3418A had the best selectivity and capture capacity of the silver minerals. In the laboratory, the total recovery of lead and silver was 65.16% and 87.81%, respectively. In industrial closed-circuit testing, flotation alone was used, which produced a total lead recovery yield of 67.71%, and a total silver recovery yield of 87.64%.

River water in industrial regions is a dynamic medium defined by random variables that cannot be described by linear equations. However, some water quality characteristics, e.g., pollutant concentrations, which look chaotically distributed are largely governed by deterministic laws resulting in periodic variations of water chemistry. Understanding this process will enable the researchers to analyse the history of the characteristics involved and to predict their future values. We provide further evidence of predictable, cyclic concentration behavior from the Iset River flowing through a heavily industrialized area in the Ob River basin, Ural Federal District, Russia. In particular, we found that the concentration of copper and nitrate can be characterized by pronounced fractals and quasi-cycles with predominant lengths of 7–8 and 4–5 months, respectively. Our results can improve forecast reliability and water use efficiency. Results from the Iset River could be potentially applicable to virtually any other river in the world, at least in temperate climate areas.