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A visible light-driven photoelectrocatalytic system was constructed based on Bi/Bi2O3/TiO2 nanotubes (NTs) to treat wastewater containing oxytetracycline and Cu2+ mixed pollutants. The surface morphology, crystal phase, elemental composition, light absorption property and photoelectrochemical activity of the synthesized Bi/Bi2O3/TiO2 NTs were investigated. The composite film, Bi/Bi2O3/TiO2 NTs was used for the photoelectrochemical removal of oxytetracycline, and it had excellent visible light photoelectrocatalytic performance. Under optimal conditions, the composite film was simultaneously used to remove coexisting oxytetracycline-Cu2+. The study results show that the reduction of Cu2+ on cathode was promoted by oxytetracycline while the degradation of oxytetracycline on photoanode was slightly suppressed by Cu2+. Also, possible photoelectrocatalytic degradation pathways for oxytetracycline-Cu2+ were analyzed by HPLC-MS.

Dye-sensitized solar cells (DSSCs) associated to the class of thin-film solar cells which have been under recent research work for more than two decades due to their low cost, simple preparation technology, low energy consumption, roll-to-roll manufacturing, eco-friendly, durable and light weight. Dye-sensitized solar cells (DSSCs) were fabricated using TiO2 as the photo anode and the composite of PANI and FeS2 as a counter electrode. The effect of the contents on the DSSC performance was investigated by adjusting the ratios of PANI and FeS2. It was found that the optimized DSSC efficiency of 0.9 % to 2.02% was achieved. The structure, surface morphology, elemental composition and functional groups of the PANI and FeS2 composites were characterized by XRD, SEM, TEM and FTIR analysis. This article provides an in-depth discussion on fabrication of DSSC based on polyaniline/FeS2 composite as counter electrode, operating conditions, prospective efficient materials and FTIR characteristics. From the obtained results, the composites of PANI and FeS2 counter electrode is served as an efficient, low-cost counter electrode (CE) material for dye-sensitized solar cells (DSSCs).

As part of the space experiment “Test”, a roll of cotton cloth fixed on the outer surface of the International Space Station for more than 10 years was delivered to the Earth in September 2019. The elemental composition of two fragments of the cloth, contaminated and clean, was determined using instrumental neutron activation analysis at the IBR-2 reactor. Along with 19 elements (Mg, Al, Cl, Ca, Ti, Cr, Mn, Fe, Co, Ni, Zn, Rb, Sr, Ag, Sb, Ba, Sm) determined on both fragments of the cloth, additional 20 elements (Na, Si, Sc, Cu, As, Se, Br, Mo, Zr, Cd, I, La, Ce, Eu, Ta, W, Re, Ir, Th, and U) were determined only on the contaminated fragment. The morphology of the rolled cotton cloth was characterized using Scanning Electron Microscopy. Gama and liquid beta spectroscopy were applied to measure the radioactivity of the cloth fragments. Possible sources of the determined chemical elements deposited on the cloth were discussed.

A thermo-sensitive film composed of polycaprolactone and poly(N-isopropylacrylamide) was fabricated via electrospinning, with ketoconazole as the model drug. The morphology, elemental composition, ...

There is a lack of aerosol measurement technology capable of quantifying, in real time, the size, concentration, and composition of large inhalable particles – specifically those with aerodynamic diameter larger than 20 µm. Aerosols of this size penetrate into the upper respiratory system upon inhalation and present surface contamination hazards upon settling. The objective of this work was to validate the performance of a prototype direct-reading particle sizer (DRPS) that counts and sizes particles via time-of-flight light scattering and determines single-particle elemental composition via laser-induced breakdown spectroscopy (LIBS). Counting, sizing, and spectral measurement efficiency were evaluated using test aerosols of multiple materials in the size range 25–125 µm. Particle sizing results showed good agreement with optical microscopy images, and LIBS measurements allow simultaneous elemental composition measurements. The relationship between the median aerodynamic diameters measured by the DRPS time-of-flight and optical microscopy was linear (Deming regression slope of 0.998) and strongly correlated (r2 > 0.999). The mean absolute difference between the median aerodynamic diameters measured by the instrument by time-of-flight and microscopy over all eight test aerosol types was 0.9 µm with a mean difference in interquartile range of 1.9 µm. LIBS spectra have been collected and analyzed to reveal spectral features of species from silver-coated glass and titanium samples. The expected system performance for future field use is considered through numeric simulations based on the instrument parameters and assumed particle size distributions. Finally, potential hardware changes to optimize detection efficiency and facilitate field use are discussed.

The elemental composition of the fragment of one of the biggest meteorites, which entered the Earth's atmosphere over Chelyabinsk, Russia was investigated by instrumental neutron activation analysis at the IBR-2 reactor. A total of 27 major and trace elements Si, Ti, Cr, Al, Fe, Mn, Mg, Ca, Na, K, V, Sc, Co, Ni, Zn, As, Se, Rb, Mo, Ag, Sb, Cs, Sm, Tm, Ir, Au, U was determined in the analyzed fragment. Obtained values were compared with the average composition of LL-chondrites and results reported by other scientific groups.

To replenish a specific consumable material, experimental samples of transport capsules were made, intended for neutron activation analysis for short-lived isotopes. The correspondence of the manufactured capsules to the real conditions of their transportation has been studied. The study of the elemental composition of the capsule material has been carried out. Analysis of the spectra of induced activity showed the presence of metal impurities in polyethylene, which must be taken into account when performing neutron activation analysis.

Granites are becoming increasingly popular and, as a result, their areas of use are expanding. In addition to their colour and particle size, the surface roughness of the machined material is becoming an important aspect of their application. In order to create a suitable surface roughness, the type of rocks located on the surface, elemental composition and microhardness of the minerals are important, because knowledge of these characteristics can be used to determine the machining parameters. Microhardness is affected by the atomic percentage values of Si, Al and Na. In addition, for some minerals, a correlation can also be established between the Si, Al and Na components.

The Inconel 718 has captured global attention for its huge applications in the aerospace and defense field. However, a limited approach is noticed to investigate this material's responses and morph...

In this paper, the contrasting properties of titanium dioxide nanoparticles in various compositions were considered. In the course of the work, methods for the synthesis of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2 and SiO2-TiO2-ZrO2 were developed; the microstructure of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2was studied; the stability of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2 was determined. The elemental composition of the oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2 has also been studied using SEM and XRD methods. It was found that SiO2-TiO2-ZrO2 nanocomposites with content of titanium dioxide from 8 to 9.5 % and zirconium dioxide from 0.5 to 2 % are completely insoluble in a highly alkaline medium. Thus, this composition is the most optimal for use as a contrast agent in optical coherence tomography.

One of the common approaches to improve the microstructure of rare-earth-barium-copper-oxide-based superconducting ceramics is an addition of a liquid source under the precursor bulk during top-seeded melt growth or top-seeded infiltration growth. The additional liquid source partially negates the change in elemental composition due to the loss of the liquid phase, which otherwise occurs. The focus of this contribution is to study the effects of various RE2O3-Ba3Cu5O8-BaO2 (RE = Sm, Gd, Dy, Y, Yb) liquid sources on the properties and microstructure of single-domain EuBCO/Ag bulks. The samples were prepared with a height of 16 mm and a diameter of 28 mm (as grown). This allowed us to study the diffusion of rare earth elements from the liquid source into the final bulk in detail. Samples were characterized by XRD, SEM, and EDS. The phase composition was studied in detail using Rietveld refinement. The influence on key superconducting properties was also examined. The addition rare earth liquid phase has significantly improved the trapped field homogeneity. Dy2O3 has yielded the highest trapped field among the studied rare earth elements. This research is significant in the field of high-performance superconducting ceramics since it allows for a better understanding of the role of the additional liquid phase during the TSMG process, the influence of different rare earth elements, and most importantly the impact of these techniques on the superconducting bulks.

Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented.

Laser-induced breakdown spectroscopy (LIBS) is an analysis technique that determines the elemental composition of a target material. Metal scraps have a range of shapes and are contaminated with other substances such as paint or dirt. This makes it difficult to recognize each piece of metal scrap accurately and to obtain clear LIBS emission spectra of the target metals. In this study, two image processing algorithms are proposed to measure the three-dimensional shapes of metal scraps and to calculate the optimized (i.e., relatively clean and flat) surface areas of metal scraps. It was confirmed that 25% higher maximum classification accuracy was achieved when LIBS spectra were acquired from optimized rather than non-optimized (i.e., contaminated) surfaces.

The constantly growing content of sulfur compounds and the increased water content in the extracted oil enhances the aggressiveness of the environments in which the technological equipment of oil depots and pipelines operates, resulting in a higher number of emergencies in the equipment of oil refineries. Thus, one of the most urgent problems is the corrosion damage to oil storage equipment and the associated consequences of flammable pyrophoric compounds formation. Finely dispersed flammable sulfides with organic impurities are formed in the equipment of the diesel fuel distillate hydrotreating unit thus accumulating on the bottoms and walls of tanks and reservoirs. This negatively affects the material balance of the hydrotreating process and increases fire and explosion hazards of the whole hydrotreating process at the refinery. For the first time, the elemental composition of pyrophoric deposits formed while storing petroleum products in the LCh-24-2000 unit was experimentally investigated. These sulfides are a flammable component of the equipment in the hydrotreating process, where diesel fuel distillates rotate. The obtained results of the test study as for the prevention of pyrophores spontaneous combustion indicate that hydrogen peroxide solutions have the highest efficiency. The practical significance of the results is in the use of experimental studies on the spontaneous combustion of pyrophoric samples in the development of the equipment cleaning terms during the hydrotreating process from pyrophoric deposits at the refinery. The experimental results of testing the ability of chemicals to prevent pyrophores spontaneous combustion can be used to reduce the risk of spontaneous combustion of pyrophoric compounds.

We have determined the boundaries of the existence and the structural features of the slab perovskite-like structure (SPS) of BaLa2–xSmxIn2O7 (0 ≤ х ≤ 1.8) and BaNd2–xSmxIn2O7 (0 ≤ х ≤ 1.8) systems have been established. The values of reliability factors RB are within the intervals of 0.037-0.057 for BaLa2–xSmxIn2O7 and 0.032-0.057 for BaNd2–xSmxIn2O7. The analysis of the structural features of SPS compounds and phases of the AIILn2B2IIIO7 (AII = Sr, Ba, BIII = Al, Fe, Sc, In) has revealed the interconnection between their composition and the features of the SPS interblock boundary. A decrease in the size of REE atoms in the series of compounds and phases of the AIILn2B2IIIO7 (AII = Sr, Ba) type leads to a gradual decrease in the interblock distance length (AII, Ln) — O and to a successive increase in the degree of deformation of interblock polyhedra (AII, Ln)O9. In the series of SrLn2B2IIIO7 (BIII = Al, Sc) compounds, a decrease in the size of REE atoms leads to a gradual change in the nature of the distribution of Sr and REE atoms in their SPS: from a partially ordered one (Ln = La) with the predominant localization of Sr atoms in the intrablock AO12 polyhedra to the completely ordered one (Ln = Eu, Gd, Tb, BIII = Sc) or almost completely ordered one (Ln = Ho, BIII = Al) with Sr a toms localized only in AO12 polyhedra, while smaller REE atoms are localized only in the interblock polyhedra. In the series of compounds and phases of the BaLn2B2IIIO7 type, there is a completely ordered arrangement of large Ba atoms in the intrablock AO12 polyhedra of their SPS, and the REE atoms only in the AO9 interblock polyhedra. It has been found that, in compounds the similar by the elemental composition to the An+1BnO3n+1- type, the thickness of the perovskite-like block significantly (by 2-6 times) increases the degree of deformation of the AO9 polyhedra and decreases the length of the A—O interblock bond. The analysis of the obtained data has shown that the values of the degree of deformation of the interblock polyhedra (АII, Ln)О9 and the length of the interblock bonds (АII, Ln)—О are among the main factors determining the stability of two-slab compounds of the AIILn2B2IIIO7-type.

The present article introduces an elemental composition analysis of copper and bronze alloys from the burials of the Lepeshkinsky Stage of the Tagar culture, burial site Serebryakovo I in the Kiya-Chulym interfluve. The research featured mounds 2, 12, and 16, which date back to 3–1 centuries B.C. The metal composition of 72 items was investigated by inductively coupled plasma atomic emission spectroscopy (ICP AES). The obtained data were subjected to statistical processing, which revealed seven chemical-metallurgical and metallurgical groups of copper-based alloys. The bronze alloys did not depend on the typology of the tools, i.e. knives, engravings, mirrors, deer plaques, etc. The results confirmed the dating of the Lepeshkinsky site between the Saragashensky and the Tesinsky Stages of the Tagar culture. The items revealed a tendency towards a decrease in the proportion of tin bronzes and average concentrations of tin ligatures. The study proved that archaeometallurgical data can help to determine the relative-chronological position of the Tagar culture burial complexes.

The combined use of non-invasive on-site portable techniques, Raman microscopy, and X-ray fluorescence spectroscopy on seven imperial bowls and two decorated dishes, attributed to the reigns of the Kangxi, Yongzheng, Qianlong, and Daoguang emperors (Qing Dynasty), allows the identification of the coloring agents/opacifiers and composition types of the glazes and painted enamels. Particular attention is paid to the analysis of the elements used in the (blue) marks and those found in the blue, yellow, red, and honey/gilded backgrounds on which, or in reserve, a floral motif is principally drawn. The honey-colored background is made with gold nanoparticles associated with a lead- and arsenic-based flux. One of the red backgrounds is also based on gold nanoparticles, the second containing copper nanoparticles, both in lead-based silicate enamels like the blue and yellow backgrounds. Tin and arsenic are observed, but cassiterite (SnO2) is clearly observed in one of the painted decors (dish) and in A676 yellow, whereas lead (calcium/potassium) arsenate is identified in most of the enamels. Yellow color is achieved with Pb-Sn-Sb pyrochlore (Naples yellow) with various Sb contents, although green color is mainly based on lead-tin oxide mixed with blue enamel. The technical solutions appear very different from one object to another, which leads one to think that each bowl is really a unique object and not an item produced in small series. The visual examination of some marks shows that they were made in overglaze (A608, A616, A630, A672). It is obvious that different types of cobalt sources were used for the imprinting of the marks: cobalt rich in manganese for bowl A615 (Yongzheng reign), cobalt rich in arsenic for bowl A613 (but not the blue mark), cobalt with copper (A616), and cobalt rich in arsenic and copper (A672). Thus, we have a variety of cobalt sources/mixtures. The high purity of cobalt used for A677 bowl indicates a production after similar to 1830-1850., NA

A metallurgical investigation was carried out on two early historic silver and copper punch marked coins. The objective was to study the metal composition, and the methods used in making of the early historic coins in India. The inductively coupled mass spectrometry was used to analyze the elemental composition of the coins. Metal formation and its mechanical properties were studied in physical metallurgical laboratory. The study revealed that the coins were not pure metal but an alloy. The silver coin contained copper as a major alloying element with other elements viz., V, Fe, Zn, Sn, Pb, As, Au in trace level while in copper the coin lead was the main alloying element with Ni, Fe, As, Au and Co in trace.

An inelastic neutron scattering system was developed to determine the elemental composition of large metallic materials. The geometrical size of the system was optimized by using Monte Carlo simulation. An experimental setup consisted of a DT neutron generator and a HPGe detector was built based on the optimized configuration and applied to analyze titanium samples. The net peak areas of titanium versus sample mass showed a linear dependence and the mass detection limit was 64 g. The prompt gamma spectra were compared to simulation data. The results demonstrated a good agreement for the signal-to-background ratio of titanium peak between measurements and simulations.

X-ray photoelectron spectroscopy (XPS) is a widely used tool for quantitative analysis of surfaces, providing critical information about elemental composition and the chemical state(s) of each elem...

The aim of this study is to evaluate the microhardness, relative surface roughness, and elemental changes of resin-based dental restorative materials (RDRMs) after gastric acid treatment. Five different RDRMs (Group 1 [Filtek Z550], Group 2 [Beautifil II], Group 3 [Vertise Flow], Group 4 [Dyract XP], Group 5 [Fuji II LC]) were used. Samples were formed by using plexiglass molds of 10 mm diameter and 2 mm thickness. A total of 50 samples (n = 10) for microhardness tests and a total of 15 samples (n = 3) for scanning electron microscopy (SEM)–energy dispersive X-ray spectroscopy (EDX) analysis were prepared. All samples of each group were treated to gastric acid, simultaneously. A Vickers microhardness tester was used to evaluate the microhardness of the upper surfaces of each sample. SEM–EDX system was used for microstructure and elemental composition detection. The SEM–EDX, microhardness and relative surface roughness analysis were made prior to treatment in gastric acid for 14 days and analysis were repeated on the 14th day. As the difference in the microhardness values of RDRMs was compared, the time-dependent variation in all RDRMs was found to be statistically significant. It was observed that a drastic decrease in microhardness values was in Beautifil II, Filtek Z550, Vertise Flow, Fuji II LC, and Dyract XP, respectively. Average decrease rate of microhardness values compared to the initial state can be listed from high to low as Beautifil II (%35.72), Vertise Flow (% 28.88), Fuji II LC (% 21.09), Dyract XP (%17.60), and Filtek Z550 (% 16.58). As a result, in in-vitro conditions gastric acid decreased microhardness while increasing the relative surface roughness of RDRMs.

As a kind of rare materials, nano-silver has broad application prospects in the fields of catalysis, medical treatment, new energy and so on. However, there are few reports on the systematic research of nano-silver in ceramic glazes. In this work, different color ceramic glazes were produced by tuning the nano-silver content and optimizing the firing process. The crystalline phase composition, micro-morphology and elemental distribution of fired glazes were analyzed and discussed in depth. The elemental composition and distribution of the samples were studied. The surface of the glazes with varying Ag contents fired under the reducing atmosphere exhibited blue-white. And the blue color is attributable to Rayleigh scattering that may arise because the phase-separation structures existed in glazes. Interestingly, the color of the ceramic glazes with varying Ag contents changed to golden-yellow when the ceramic glazes were fired under the air atmosphere. Golden-yellow color of the samples fired under the air atmosphere is mainly attributable to the silver nano-particles, though Ag+ may be existed in the glazes.

Water droplet impacting on a slanted dusty hydrophobic surface is examined in relation to dust mitigation from surfaces. Impacting droplet characteristics including droplet spreading/retraction rates, slipping length, and rebound heights are analyzed via high-speed recording and a tracker program. The environmental dust characteristics in terms of size, shape, elemental composition, and surface free energy are evaluated by adopting the analytical methods. The findings reveal that the dynamic characteristics of the impacting droplet on the slanted hydrophobic surface are significantly influenced by the dust particles. The maximum droplet spreading over the dusty surface becomes smaller than that of the nondusty surface. The presence of the dust particles on the slanted hydrophobic surface increases energy dissipation, and the water droplet slipping length over the surface becomes less than that corresponding to the nondusty surface. Impacting droplet fluid infuses over the dust particle surface, which enables mitigation of dust from the surface to the droplet fluid. A dust-mitigated area on the slanted surface is larger than that corresponding to the horizontal surface; in which case, the area ratio becomes almost six-fold, which slightly reduces with increasing Weber number. The optical transmittance of the dust-mitigated surface by the impacting droplet remains high.

In medium/high entropy alloys, their mechanical properties are strongly dependent on the chemical-elemental composition. Thus, searching for optimum elemental composition remains a critical issue to maximize the mechanical performance. However, this issue solved by traditional optimization process via “trial and error” or experiences of domain experts is extremely difficult. Here we propose an approach based on high-throughput simulation combined machine learning to obtain medium entropy alloys with high strength and low cost. This method not only obtains a large amount of data quickly and accurately, but also helps us to determine the relationship between the composition and mechanical properties. The results reveal a vital importance of high-throughput simulation combined machine learning to find best mechanical properties in a wide range of elemental compositions for development of alloys with expected performance.

The effect of the size of the enthalpy formation, the hydrogen content and the oxygen saturation coefficient (α) of the organic oxidizer of solid composite propellants on the optimal value of binder α, providing the maximum values of the specific impulse in metal-free compositions based on a specific oxidizer, is studied. The quantitative dependence of the maximum attainable specific impulse of binary compositions of propellants containing a high-enthalpy organic oxidant and a binder on the enthalpy of the formation of the oxidizer, the hydrogen content in it, and the value of α is found.

Possibility of determination of the fragments and articles made of different grades of steel aluminium and copper alloys and their affiliation to the common melt was examined via the methods of photoelectric spectral analysis based on composition of micro-impurities. Chemical elements with micro-impurities were revealed; they allow to determine affiliation of metal fragments to one melt. Ultimately possible deviations of micro-impurities within one melt were obtained. The technique allowing to establish affiliation of fragments to the common melt based on their elementary composition of micro-impurities with minimal amount of measurements was suggested based on the obtained results. The minimal geometric size of a sample available for analysis was determined; it allows to classify the examined fragments to one melt based on the results of investigation of expanded elementary composition of micro-impurities. Practical opportunities of this technique were displayed on the example of the alloys with different chemical composition.

As one of the most important imaging modalities, magnetic resonance imaging (MRI) still faces relatively low sensitivity to monitor low-abundance molecules. A newly developed technology, hyperpolarized 129Xe magnetic resonance imaging (MRI), can boost the signal sensitivity to over 10 000-fold compared with that under conventional MRI conditions, and this technique is referred to as ultrasensitive MRI. However, there are few methods to visualize complex mixtures in this field due to the difficulty in achieving favorable “cages” to capture the signal source, namely, 129Xe atoms. Here, we proposed metal–organic frameworks (MOFs) as tunable nanoporous hosts to provide suitable cavities for xenon. Due to the widely dispersed spectroscopic signals, 129Xe in different MOFs was easily visualized by assigning each chemical shift to a specific color. The results illustrated that the pore size determined the exchange rate, and the geometric structure and elemental composition influenced the local charge experienced by xenon. We confirmed that a complex mixture was first differentiated by specific colors in ultrasensitive MRI. The introduction of MOFs helps to overcome long-standing obstacles in ultrasensitive, multiplexed MRI., Metal organic frameworks with tunable pore structures are able to provide varied chemical environments for hyperpolarized 129Xe atom hosting, which results in distinguishing magnetic resonance signals, and stains ultra-sensitive magnetic resonance imaging (MRI) with diverse colors.

The results of experiments on the application of the method of glow discharge optical emission spectroscopy for the profile analysis of vacuum-deposited single- and double-layer films of multicomponent ferrite–garnets of various compositions before and after crystallization annealing have been presented. The presence of internal and external transition layers has been revealed and the modification of their elemental composition during crystallization and at different synthesis sequences of individual components in ferrite–garnet heterostructures have been studied.

The oxidation of an ultra-high-temperature ceramic material (HfB2-30 vol%SiC)-10 vol%Ta4HfC5 produced by reactive hot pressing at a temperature of 1800°C (pressure 30 MPa, holding time 30 min, Ar) under long-term exposure (2000s) to a supersonic flow of dissociated air was studied. It was found that the sample surface temperature, set during heating and oxidation on a high-frequency induction plasmotron, was significantly lower than for samples unmodified with super-refractory tantalum-hafnium carbide Ta4HfC5. It was also found that under similar exposure conditions there was no sharp temperature rise to 2500−2700°C – the temperature did not exceed 1850°C. Features of the oxidised material surface microstructure were noted, in particular, the existing gradient in the elemental composition and morphology of the oxide particles forming the surface. It was found that the main crystalline oxidation product was a complex hafnium-tantalum oxide Hf6Ta2O17, which had a phase stability up to temperatures of ∼2250°C, which set it apart from individual hafnium oxide.

Mogao grottoes is famous for its exquisite murals, these murals were composed of pigment powders arranged in successive layers. The depth profile of these painted layers is a key information for studying mural diseases and providing a scientific basis of suitable restoration and conservation on the ancient murals. However, the depth profile was carried out only from cross-sectional analysis of mural fractions at present, which damaged murals and required complex measurements. Laser-induced breakdown spectroscopy (LIBS) was introduced for depth profile of painted layers owing to its multi-elemental capability, rapid, no preparation and the ability to resolve depth profiles of elemental composition. In this work, as one of the most commonly presented on Mogao murals, the green painted layers were investigated by LIBS technique. The color shades of different green areas were demonstrated with the pigment sizes, so it is essential to study the influence of pigment sizes on laser ablation depth for thickness analysis of the green layers. The simulated green layers composed of five different pigments sizes were prepared and analyzed by LIBS technique coupling with cross-section analysis, relationships of laser pulses and ablation depth in each pigment size fraction were obtained quantitatively. It was found that the average ablation rate (AAR) of laser pulse gradually become larger with decreasing of pigment sizes on green layers. The relationship can be used to achieve the measurements of green layer thicknesses in situ with using LIBS on Mogao murals.

In this article, three types of surface-modified g-C3N4 (H+/g-C3N4, BCQDs/g-C3N4, and H+/BCQDs/g-C3N4) with unique photocatalytic properties have been successfully fabricated by simple and low-cost strategies. The morphology, elemental composition, textural properties, structural information, and photoelectric properties of the as-prepared materials are systematically characterized. Subsequently, the as-prepared materials are applied to Cr(VI) reduction, 4-FP degradation, and simultaneous Cr(VI) reduction with 4-FP degradation photocatalytic systems under normal and anoxic conditions. Based on the photocatalytic test results, we successfully constructed a macro-thermodynamic model to reveal the essential laws of synergistic photocatalytic effects. The constructed macro-thermodynamic model is suitable for complex photocatalytic systems and is of great significance for the application of photocatalytic technology in real wastewater treatment with multiple pollutants.

Harnessing the energy of photons by photocatalytic semiconducting materials is a topic of paramount interest in the present era because of its sustainable eco-friendly impact. The harnessed energy by photocatalyst is intricately employed for a plethora of photocatalytic applications, such as pollutant remediation, energy conversion, organic transformations and many more. Hence, the global research community has focused their interest on the design and development of cost-effective and actively efficient photocatalytic semiconductors crafted to the needs of a desired photocatalytic process. In this regard, the stimulation of a broad range of characterization techniques becomes an imperative necessity to reveal various physico-chemical properties of the semiconductor photocatalyst. This review aims to summarize the sophisticated characterisation techniques that are used to analyse various organic, inorganic and hybrid type photocatalysts by qualitative and quantitative methods. In detail, this review is centred on the techniques utilised to contemplate, as well as correlate the physical structure, topography, chemical state, elemental composition, electrochemical properties and band structures of a wide range of photocatalysts. The discussion of each characterization method consists of a concise fundamental explanation, followed by proper exemplification intended to disseminate to materials chemists, predominantly individuals who are near the beginning of their careers focused on the development of competent photocatalysts.

Austenitic stainless steels possessing excellent mechanical properties, Exceptional corrosion resistant, non-magnetic, non-hardenable by heat treatment, are very robust, and are easily formed and fabricated. The AISI 304 and AISI 316 grades are two of the most widely used austenitic stainless steel grades. This investigation was carried out to characterize the microstructures of the welded joints of plasma arc butt obtained on identical and dissimilar combinations of AISI 304 and AISI 316. The weldments were characterized by a combination of Image Analyzer and Scanning Electron Microscope (SEM) techniques. Finally Energy Dispersive X-Ray Analysis (EDAX) used to identify the elemental composition of materials after welding.

This study reports novel approaches for the detection of gunshot residues (GSR) from the hands of individuals using Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The methods' performance was evaluated using 159 GSR standard and authentic samples. Forty specimens generated from characterized microparticles were used as matrix-matched primer gunshot residue (pGSR) standards to examine the elemental profiles of leaded and lead-free residues, compared to SEM-EDS and solution-ICP-MS. Also, 119 authentic skin samples were analyzed to estimate error rates. Shooter samples were correctly classified into three categories based on their elemental composition (leaded, lead-free, or mixed pGSR). A total of 60 non-shooter samples were used to establish background thresholds and estimate specificity (93.4% for LA-ICP-MS and 100% for LIBS). All the authentic leaded items resulted in the detection of particle(s) with composition characteristic of pGSR (Pb-Ba-Sb), as observed by simultaneous elemental identification of target analytes at the exact ablation times and locations. When considering the pre-characterized elemental composition of these primers as the "ground truth", LA-ICP-MS resulted in 91.8% sensitivity (true positive rate), while LIBS resulted in 89.2% sensitivity. Particles containing Ba, Bi, Bi-Cu-K, and Cu-Ti-Zn were found in the lead-free residues. Identification of lead-free GSR proved more challenging as some of these elements are common in the environment, resulting in 85.2% sensitivity for LA-ICP-MS and 44.4% for LIBS. Overall accuracies of 94.9% and 88.2% were obtained for the LA-ICP-MS and LIBS sets, respectively. LA-ICP-MS provided an additional level of confidence in the results by its superior analytical capabilities, complementing the LIBS chemical profiles. The laser-based methods provide rapid chemical profiling and micro-spatial information of gunshot residue particles, with minimal destruction of the sample and high accuracy. Chemical mapping of 25 micro-regions per sample is possible in 2-10 minutes by LIBS and LA-ICP-MS, offering new tools for more comprehensive forensic case management and quick GSR screening in environmental and occupational sciences.

Annotation. The article describes the results of a study of experimentally caused damage to various types of non-biological material (simulators of clothing fabrics) under the action of different models of electroshock devices. Particularly, the morphological features of the damages and the elemental chemical composition in the areas of damages are established. In the study, 120 experimental objects were investigated – damage to four types of clothing fabrics (imitators of clothing fabrics – cotton knitwear, linen, synthetic fabrics) caused by the action of three models of electric shock devices. Applied research methods: visual examination (including via optical devices), morphometric, photographic, X-ray fluorescent spectral analysis, statistical. The research results are processed by standard methods of variation statistics. The purpose of the study is to establish the forensic diagnostic criteria for assessing damage to various fabrics (materials) of clothing, causing by the action of electric shock devices. In the course of the experiment, certain morphological features of damage were established, which are formed as a result of the action of electroshock devices on various types of materials (imitators of clothing fabrics). The results of the study indicate that the design features of electro-shock devices are reflected in the morphological pattern of damages on the tissues of clothing, namely, in the nature of the mutual arrangement of injuries, the distance between them, which can be used in forensic practice, as a sign indicating the action of an electroshock device specific model. When carrying out X-ray fluorescence spectral analysis from areas of material damage (simulators of clothing fabrics), metal deposits were found, which, in terms of their elemental composition, corresponded to the chemical composition of the contact electrodes of electroshock devices that caused damage. This regularity can be used as an objective sign of establishing the fact of the action of an electroshock device with a certain elemental composition of the metal of the contact electrodes.

This paper discusses about the effect of substrate type on structure of titanium dioxide thin film deposited by atomic layer deposition technique using titanium tetrachloride and deionized water as precursors. The substrates investigated are silicon (100), cover glass and titanium, and the depositions were performed at temperatures ranging from 300ºC to 450 ºC. We observed through Rutherford backscattering spectrometry that the TiO2 thin films grown on both substrates are stoichiometric. Grazing incidence x-ray diffraction showed that rutile phase could be obtained in almost pure phase at temperature of 450 ºC, however only for glass and titanium substrates. For the case of silicon (100) substrate, the anatase phase was preponderant for process temperatures investigated.

This study compared the topography of different titanium surface structures (TiO2 nanotube and grain) with similar elemental compositions (TiO2 and fluorine [F]) on the Ti surface. High magnification indicated that the surfaces of the control and etching groups were similar to each other in a flat, smooth form. The group anodized for 1 h was observed with TiO2 nanotubes organized very neatly and regularly. In the group anodized for 30 min after etching, uneven wave and nanopore structures were observed. In addition, MTT assay showed that the F of the surface did not adversely affect cell viability, and the initial cell adhesion was increased in the 2.8% F‐incorporated TiO2 nanograin. At the edge of adherent cells, filopodia were observed in spreading form on the surfaces of the anodizing and two‐step processing groups, and they were observed in a branch shape in the control and etching groups. Moreover, cell adhesion molecule and osteogenesis marker expression was increased at the F‐incorporated TiO2 nanostructure. In addition, it was found that the expression of p‐extracellular signal‐regulated kinase (ERK) and p‐cAMP response element‐binding protein (CREB) increased in the TiO2 nanograin with the nanopore surface compared to the micro rough and nanotube surfaces relative to the osteogenic‐related gene expression patterns. As a result, this study confirmed that the topographic structure of the surface is more affected by osteogenic differentiation than the pore size and that differentiation by specific surface composition components is by CREB. Thus, the synergy effect of osteogenic differentiation was confirmed by the simultaneous activation of CREB/ERK.

Samples of ceramics based on barium ferrite (BF) and barium titanate (BaTiO3) were obtained and studied. We have analyzed the elemental composition of the obtained ceramics. Based on a study of pyr...

The physical properties of crude bio-oils preclude their direct use as fuel. Specifically, their high oxygen content results in undesirable acidity and poor thermal stability. Therefore, the remova...

Objective To define SEM characteristics that may aid identification of sialoliths. Materials: Two sialoliths from modern patients affected by sialadenitis. Methods Samples were coated with silver and subjected to scanning electron microscopy using an energy-dispersive X-ray spectroscopy detector. Samples were then sectioned to permit study of the internal structure. Results Sialoliths show an external smooth surface with no distinctive features. Internal structures consist of a distinctive aggregate of coarse granules of different sizes surrounded by a lamellar coat. Elemental composition consists of carbon, phosphate, calcium and oxygen, with traces of magnesium. The proportion of these elements differs between the core and the surface. Conclusion Although elemental composition is not specific, SEM analyses of sialoliths greatly differ from those of sesamoid bones, gallstones and nephroliths. Therefore, SEM analysis constitutes a useful tool for the precise identification of small calcified structures recovered during archaeological excavations. Significance Precise identification of calcified structures may provide information about nutritional and/or pathological aspects of past individuals. Limitations Sialoliths are less common than other types of calcifications, and only two cases were analyzed in this study. Future prospects SEM technology should be applied to identify the etiology of all minute calcified remains recovered during archaeological excavations of burial sites.

The results of studies on using a concentrated radiation flux to obtain fused materials based on kaolinite clay and high-alumina waste are reported. The phase composition, microstructure, and elemental composition of the synthesized materials were determined. It was found that the additive content 10 – 20% by weight and melt cooling rate about 103 K/sec are preferable for the formation of the optimal microstructure in the form of mullite needles with different orientations.

Phase-pure magnesium ferrite (MgFe2O4) spinel nanocrystals are synthesized by a fast microwave-assisted route. The elemental composition is optimized via the ratio of the precursor mixture and cont...

The article is aimed at the study of structural features and phase chemical composition in 3.6 wt.% C-15 wt.% Cr-2 wt.% Mo cast iron prepared with adding 0.50 wt.% boron. The work was fulfilled using optical and electron scanning microscopy, EDS, XRD, hardness measurement, and thermodynamic modelling. It was found that due to boron effect the cast iron acquired hypereutectic structure consisting of the primary M7C3 carbides (5.3 vol. %) and the eutectics based on M7C3 carbide (rosette-shaped cells) and M3C carbide (coarse-net-shaped cells or Ledeburite-shaped cells). The total amount of carbide phases was 51.8 vol.% whereas the volume fractions of M7C3-eutectic cells and M3C-eutectic cells were 21.0 vol.% and 74.7 vol.% respectively. The matrix comprised austenite, martensite and pearlite whereas austenite volume fraction was measured as 32 vol.%. Chromium and molybdenum were unevenly partitioned in phases performing the opposite character of a distribution. The primary carbides contained about 37 wt.% Cr and 1.6 wt.% Mo with the stoichiometry of (Fe3.88Cr2.76Mo0.22Mn0.12Si0.02)C3. Substantial part of carbide precipitates (primary and eutectic both) exhibited the duplex nature presenting Cr-rich/Mo-depleted core (M7C3 carbide) and Cr-depleted/Mo-rich shell (M3C carbide). Duplex carbides were closely adjusted to austenite + M3C eutectic cells to be the starting interface for their solidification. A minor amount of micron-sized areas with 67.5 wt.% Mo and 4.6 wt.% Si were observed to be presumed as M6C carbide. The cast iron was subjected to holding at 950 °C for 2 hours with subsequent oil-quenching. This treatment caused the precipitation of fine secondary carbides followed by the martensite transformation which resulted in significant hardness increase from 672 HV (as-cast) to 1038 HV. The solidification sequence is discussed in terms of structure observation and Thermo-Calc modelling.