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In this research, stir casting was used to create the aluminium alloy (AA7075) composite filled with 10wt.% zirconia (ZrO2) particles as reinforcement. Die sinking electric discharge machining (EDM) was used to examine the machining characteristics of the proposed composite. The machining experiments were executed in accordance with the L9 orthogonal layout. Here, the material removal rate (MRR) and surface roughness (SR) were taken into account as the output responses, and the discharge current (Ip), pulse on-time (Ton), and pulse off-time (Toff) were taken as the machining parameters. To determine the optimal parameter conditions for the output responses, the technique for order preference by similarity to ideal solution (TOPSIS) approach was applied. According to the experimental findings, the optimum settings of the parameters are determined at 15amps of ‘Ip’, 750μs of ‘Ton’ and 50μs of ‘Toff’. ANOVA results stated that ‘Ton’ has the most notable factor with a contribution of 90.85%. The interaction effect of parameters on the responses was shown by the contour plots. The confirmatory experiment was finally conducted at the optimum machining parameter settings, and it was found that the error only occurred in 8.4%. [ABSTRACT FROM AUTHOR]

This investigation explores the application of electrical discharge machining (EDM) to ceramic composites constructed from Si3N4–TiN (Syalon 501) by testing both square and cylindrical electrodes. Various experimental methods have been employed, including design-of-experiments (DoE), Grey relational analysis (GRA), analysis of variance (ANOVA), confirmation testing, and scanning electron microscopy (SEM), in an effort to optimize machining settings and comprehend their effect on performance. While ANOVA revealed crucial parameter levels influencing overall machining conditions as measured by the grey relational grade (GRG), the sophisticated method of GRA considerably improved the machining characteristics. Significant improvements in the EDM process were shown experimentally, resulting in outstanding results for material removal rate (MRR), surface roughness (SR), and electrode wear rate (EWR). In particular, numerous benefits of the square electrode layout over the more common cylindrical arrangement stood out. All of the aforementioned resulted in an impressively high MRR (measured at 0.0281gm/min), a low EWR (at 0.0020gm/min), and a significant improvement in SR (at 0.3150μm). The GRG value was 0.0163 for the square electrode design, which was excellent, and 0.0025 for the cylindrical electrode, which was significantly better. The optimized parameters were successfully used, especially with the square electrode arrangement, leading to significant improvements in MRR and decreases in EWR. On the other hand, surface quality was negatively affected by larger parameter values, which increased the development of microfractures, particularly when using the square electrode design. In any case, our study provides strong proof that adjusted settings can greatly improve EDM performance, allowing for accurate machining of Si3N4–TiN composites with increased MRR, great surface texture, and reduced electrode wear. In conclusion, our study provides useful information to improve EDM procedures for Si3N4–TiN ceramic composites, as well as practical insights into increasing the efficiency and quality of EDM operations in a variety of industrial sectors. [ABSTRACT FROM AUTHOR]

This study examined the effect of the Sr concentration in SrK/CaO catalysts based on oyster shells for the transesterification of canola oil. The CaO support was obtained by mixing 800 °C calcined oyster shell and limestone. Then, K and Sr were impregnated simultaneously at three different Sr/(Sr + K) molar ratios, 0.2, 0.3, and 0.4, and calcined at 800 °C. XRD, SEM, and Hammett indicators were used to characterize the catalysts. The reaction conditions were 60 °C, 1 h, met/oil = 12.5, and a catalyst loading of 7 wt%. The results showed that a Sr/(Sr + K) = 0.3 produces larger K2Sr(CO3)2 crystals that contribute synergistically to the catalytic activity. At Sr/(Sr + K) > 0.3, the K and Sr are segregated, decreasing the alkaline character and activity. Also, the optimization of WCO transesterification conditions was carried out by Box–Behnken response surface design with SrK/CaO-0.3 catalyst. The theoretical optimal conditions were 70 °C, 1.5 h, and a met/oil = 10, which achieved 79 % of biodiesel yield. Nonetheless, the produced WCO biodiesel did not present acceptable quality, and this reactive system increased the lixiviation of the active phases. [ABSTRACT FROM AUTHOR]

A geochronological and isotope–geochemical study of alkaline basalts from three areas of young magmatism within the northeastern part of the Arabian Plate (Southeastern Turkey), Batman, Kurtalan and Alemdağ, was carried out. The obtained isotope data have indicated that the volcanism in the studied region developed over a 5-Ma period from the end of Miocene to the middle Pleistocene during four pulses separated by breaks in magmatic activity: 6.1–4.9 Ma (Batman area, hawaiites), ~3.0 Ma (Alemdağ plateau, phase I, basalts), 2.0–1.9 Ma (Alemdağ plateau, phase II, tephrites), and 1.5–1.3 Ma (Alemdağ plateau, phase III, basalts; Kurtalan area, basalts). A comparison of spatial–temporal changes of magmatic activity evolution in the studied part of the Arabian Plate and within the largest basalt plateau of Arabian foreland, Karacadağ Plateau, located to the west, was carried out. The results of Sr–Nd–Pb isotope–geochemical studies show that the development of young basalt volcanism in the Arabian Plate was characterized at different time by the contribution of various mantle sources in magma generation under this region. Initial pulses of magmatic activity are associated with melting of Arabian subcontinental lithospheric mantle (SCLM). The processes of fractional crystallization combined with crustal assimilation (AFC) have played an important role in the petrogenesis of lavas as well. Later, a deep mantle source (PREMA) with a depleted isotopic composition played a leading role in the formation of basaltic magmas of increased alkalinity. The melts generated by this source were mixed with the SCLM material in various proportions at different stages of magmatism with a limited participation of AFC processes in the petrogenesis of the rocks. It was concluded that young basalt volcanism of increased alkalinity in the northeast of the Arabian Plate is not related to the collision of the Eurasian and Arabian plates genetically, but presumably manifested here as a result of the migration of the initial rift geodynamic setting from the Red Sea basin to the north along Levantine and East Anatolian transform faults due to directed convection flows in the lower part of mantle under this part of the Earth. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to investigate and develop a rapid and effective method for the immobilization of Sr in the event of a nuclear leakage incident. Coal gangue, an underutilized form of solid waste from the coal industry, can be used as a raw material for curing Sr due to its high content of silica–alumina oxides. In the present study, Sr was successfully solidified in cancrinite synthesized using a hydrothermal method with coal gangue as raw material. A stable cancrinite phase was formed at a relative alkali concentration of more than 6 M. When the Sr/Al(Si) ratio was <1/6, cancrinite was the only stable phase that varied with the hydrothermal temperature and time. When the Sr/Al(Si) ratio increased to 1/2, the cancrinite phase completely disappeared, and a new strontium feldspar phase (SrAl2Si2O8) appeared. PCT leaching experiments showed that when Sr/Al(Si) < 1/6, the Sr leaching rate of Sr-cancrinite samples obtained by hydrothermal synthesis at 180 °C for 24 h was very low. [ABSTRACT FROM AUTHOR]

Petrogeochemical data on basalts (lithophile elements and Sr–Nd–Pb isotopes, liquidus olivine and spinel compositions) from the transition zone of the Southwest Indian Ridge (SWIR) in the Du Toit–Andrew Bain fault zone indicate significant differences in their composition. Tholeiites enriched in Na and depleted in Fe (Na-TOR genetic type) are developed within the rift valley adjacent to the faults. Deep-type basalts (TOR-1) are present in the western wall of the Andrew Bain Fault. The outpouring of these magma types reflects a possible change in geodynamic setting during formation of this zone: from deep and high temperature to shallower magma generation conditions (Sushchevskaya et al., 2022). Differences in the primary melts of tholeiites from the rift valley and the Andrew Bain Transform Fault are also traced in the composition of liquidus olivine. The olivines from rift valley are similar to the typical Na-TOR olivines with Mg number of Fo88-87, low Ni and elevated Mn contents. On the contrary, olivines in tholeiite from the Andrew Bain Fault Zone are enriched in Ni and depleted in Mn, which may indicate the involvement of pyroxenite in melt generation. This component is either oceanic lithosphere recycled through the deep mantle or fragments of previously formed oceanic crust, which were subsequently involved in melting during the spreading axes jumping. A similar process is typical of the Bouvet Triple Junction, where the trace-element composition of olivine shows significant heterogeneity. The radiogenic composition of Pb and Sr of the Andrew Bain Fault tholeiites are similar to those of enriched magmas from such Indian Ocean rises as Crozet, Marion and Bouvet, but differ from those of the Conrad and Af. Nikitin rises. The source of such tholeiite melts is close in composition to the model HIMU type (with high U/Pb), which likely contains an admixture of EM-II component (with elevated Rb/Sr). [ABSTRACT FROM AUTHOR]

The occurrence of bone disorders is steadily increasing worldwide. Bone tissue engineering (BTE) has emerged as a promising alternative to conventional treatments of bone defects, developing bone scaffolds capable of promoting bone regeneration. In this research, biomimetic scaffolds based on ion-substituted calcium phosphates, derived from cuttlefish bone, were prepared using a hydrothermal method. To synthesize Mn2+-substituted scaffolds, three different manganese concentrations (corresponding to 1, 2.5, and 5 mol% Mn substitutions for Ca into hydroxyapatite) were used. Also, syntheses with the simultaneous addition of an equimolar amount (1 mol%) of two (Mg2+ and Sr2+) or three ions (Mn2+, Mg2+, and Sr2+) were performed. A chemical, structural, and morphological characterization was carried out using X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The effects of the ion substitutions on the lattice parameters, crystallite sizes, and fractions of the detected phases were discussed. Multi-substituted (Mn2+, Mg2+, and Sr2+) scaffolds were coated with polycaprolactone (PCL) using simple vacuum impregnation. The differentiation of human mesenchymal stem cells (hMSCs), cultured on the PCL-coated scaffold, was evaluated using histology, immunohistochemistry, and reverse transcription–quantitative polymerase chain reaction analyses. The expression of collagen I, alkaline phosphatase, and dentin matrix protein 1 was detected. The influence of PCL coating on hMSCs behavior is discussed. [ABSTRACT FROM AUTHOR]

The method of cooling aqueous solution and the Sankaranarayanan–Ramasamy technique were used for the preparation of urea doped KDP single crystals with additive concentrations of 0.1, 0.5, and 1 mol%. The single crystals were grown unidirectionally from seeds that were inclined to type I phase-matching angle, the requirement for maximal second harmonic generation (SHG) efficiency. The analysis employed to study the chemical composition, crystal structure, bonding vibrations, and optical properties of the crystal samples was energy-dispersive X-ray spectroscopy, X-ray diffraction patterns, Raman spectroscopy, ultraviolet-visible spectroscopy, and SHG measurement respectively. The differences in chemical composition, crystal structure, optical transmittance, and SHG efficiency of the parts on each urea doped KDP single crystal rod were explained by the variation in the growth sector boundary. This work aims to improve the second-order nonlinear optical coefficient of KDP crystals and suggests which part of the urea doped KDP crystal rod grown by the SR technique is most acceptable for frequency-doubling applications. [ABSTRACT FROM AUTHOR]

Tumors in the brain and pancreas are formed by abnormal cells accumulating in a tissue mass in the human body. The standard technique for MRI tumor detection and categorization would be to investigate them utilizing MR medical images. Due to a discrepancy among many brain and image characteristics, an MR picture is segmented at the early stage of diagnosis. The tumor identification framework is processed in the following order: The initial pre-processing (or) filtering is carried out using a Modified Decision-Based Coupled Windows Median Filter (MDBCWMF) technique. This stage's output is transmitted to a unique Distance Metric-based variant of the Fuzzy C-Means algorithm for segmenting MDM-FCM. This method results in a lower segmentation error. The image is then feature extracted using a Gray-Level Co-Occurrence Matrix (GLCM) algorithm and classified using a parameterized combination of Back Propagation Neural Network (BPNN) and Sparse Representation (SR) approaches known as Dynamic Score Level Integration (DSLI). Compared to other state-of-the-art methodologies, MDM-FCM segmented yields 0.9674 and 0.9481 in classification yield 97.84% and 95.62% accuracy for brain and pancreas images, experimental valuation being done with Datasets from TCIA. [ABSTRACT FROM AUTHOR]

In this paper, Φ25 mm lanthanum bromide scintillation crystals with 5%Ce3+ and different Sr2+ doping concentrations (0.1%, 0.3%, 0.5% in molar ratio) were successfully grown by spontaneous nucleation vertical Bridgman method. X-ray excited emission spectra, transmission spectra and pulse height spectra of these crystals were measured. Results show that, the emission spectra waveform of LaBr3:Ce crystals with different Sr2+ doping concentrations is basically consistent under X-ray excitation, and the emission peak shows a significant red shift compared with that of sample without Sr2+ doping. With the increase of Sr2+ doping concentration, the emission peak of LaBr3:Ce,Sr crystal shows a slight red shift. There is no obvious absorption peak range from 350 to 800 nm of LaBr3:Ce,Sr crystals with different Sr2+ doping concentrations. Compared with LaBr3:Ce crystals, transmittance of 0.3% and 0.5% Sr2+ doped LaBr3:Ce crystals decrease. In addition, with the increase of Sr2+ doping concentration, the energy resolution of the crystal increases correspondingly. LaBr3:Ce,0.5% Sr crystal has the highest energy resolution of 2. 99%@662 keV. The energy resolution of the encapsulated LaBr3:Ce,0.5%Sr crystal with size of Φ25 mm x 25 mm is 2.93%@662 keV. [ABSTRACT FROM AUTHOR]

The activity and product selectivity of Na2WO4-MnO2-CeO2/TiO2 (MNTiCe) catalysts promoted by Sr and Mg in the oxidative coupling of methane (OCM) reaction was studied. The OCM reaction holds significance due to its potential for methane utilization, production of valuable chemicals, and environmental benefits. The Sr and Mg promoters are added simultaneously or after the impregnation of Ce to the catalyst. The catalyst activity results showed that the simultaneous addition of Sr and Mg promoters along with Ce provides more C2 selectivity for the catalyst. These results show that the C2 selectivity of the MNTiCe catalyst in the OCM reaction is improved by simultaneous Sr and Mg addition, in which the optimum loading of Sr is 0.75 wt% and the optimum loading of Mg is 0.25 wt%. According to the XPS results, the catalytic surface of catalyst loading with 0.75 wt% of Sr has a higher concentration of O2− species and increases the ability of the catalyst in the OCM reaction. The surface areas of all catalysts are lower than 10 m2/g which is suitable for OCM reaction and increased by the addition of Sr and Mg. According to the TPR results the catalyst reduction in simultaneously Sr and Mg loading catalysts are higher than in unpromoted catalyst. [ABSTRACT FROM AUTHOR]

Syngas is produced through the carbon dioxide reforming of methane. The traditional nickel-based catalysts are substantially destroyed by carbon deposition. The reforming reaction was conducted in a tubular microreactor at 700 °C using bimetallic Ni catalysts supported over 37% Al2O3 and 63% MgO mixtures. The impregnation process formed the catalysts, which were subsequently examined by N2-physisorption, XRD, H2-TPR, TGA, and Raman spectroscopy. The 2.5Ni+2.5Co/37%Al2O3+63%MgO bimetallic catalyst, which displayed 72% and 76% conversions of CH4 and CO2 over the course of a seven-hour procedure, was discovered to be the most active in DRM. The bimetallic catalyst with the largest weight loss in TGA, 2.5Ni+2.5Fe-MG63, had a loss of 61.3%, a difference of 26% and 21% in the activity performance of CH4 and CO2, respectively, of the tested bimetallic Ni catalysts was recorded. The long-time of 30 h on-stream CH4 and CO2 conversion reactions for 2.5Ni+2.5Co-MG63 and 2.5Ni+2.5Ce-MG63 catalysts showed the catalysts' high stability. The TPO analysis for the 2.5Ni+2.5Cs-MG63 catalyst showed a peak at 650 °C, attributed to the oxidation of the filamentous carbon, whereas the TPO analysis for the 2.5Ni+2.5Co-MG63 catalyst depicted a peak at 540 °C, ascribed to the presence of amorphous/graphite carbon. [ABSTRACT FROM AUTHOR]

Biochemical reactions in cells serve as the endogenous source of heat, maintaining a constant body temperature. This process requires proper control; otherwise, serious consequences can arise due to the unwanted but unavoidable responses of biological systems to heat. This review aims to present a range of responses to heat in biological systems across various spatial scales. We begin by examining the impaired thermogenesis of malignant hyperthermia in model mice and skeletal muscle cells, demonstrating that the progression of this disease is caused by a positive feedback loop between thermally driven Ca2+ signaling and thermogenesis at the subcellular scale. After we explore thermally driven force generation in both muscle and non-muscle cells, we illustrate how in vitro assays using purified proteins can reveal the heat-responsive properties of proteins and protein assemblies. Building on these experimental findings, we propose the concept of 'trans-scale thermal signaling'. [ABSTRACT FROM AUTHOR]

Adsorption behavior of nuclides in natural barrier media of nuclear waste disposal sites is essential for safe disposal of nuclear waste. Taking a common mineral in clay rock of illite as the research object, the adsorption behavior of illite on Sr was explored through static adsorption experiments. The adsorption reaction mechanism of illite on Sr was explored by combining adsorption kinetics model and various characterization analysis methods. The results show that the adsorption behavior of illite on Sr was divided into two stages: rapid adsorption (t≤60 min) and slow adsorption to equilibrium (60 min≤t≤240 min), which conformed to the quasi-firstorder and quasi-second-order kinetic models. In the rapid adsorption stage, physical adsorption is the main mechanism, mainly for liquid film diffusion. In the slow adsorption stage, chemical adsorption is the main mechanism. The cation exchange reaction between Ca2+, Mg2+ and Sr and the complex reaction between CO2-3, —OH and Sr are the main adsorption mechanism. [ABSTRACT FROM AUTHOR]

The study aims to investigate the role of green innovation subsidy policies (GISPs) in reducing the systemic risk (SR) of green innovative enterprises (GIEs). This paper studies the subject behaviours and system evolution rules to construct the artificial GIEs system, and investigates the effects of the GISP intervention and the intention for green R&D on the SR. Firstly, the internal and external factors of the constructed model can significantly reduce the number of bankruptcies and the SR of GIEs. In addition, the joint effect is better than a single one and has an obvious 'synergy effect'. This study has practical implications for GIEs, banks, and governments. First, we find the SR of the GIEs. In addition, we adopt bankruptcies to measure SR and consider the liquidity early warning mechanism. Moreover, we focus on the effects of GISP on their SR and emphasize the function of the 'implicit guarantee mechanism'. More importantly, we compare the forms of GISPs and analyze their possible internal and external mechanisms to reduce SR. [ABSTRACT FROM AUTHOR]

In this work, a highly carbonated liquid has been utilized as a dielectric medium in the EDM process. The effect of the dielectric medium has been investigated and then, finally, compared with EDM oil. The outcomes have demonstrated that discharge energy density has escalated to fierce-extent, thus, removing a voluminous amount of material from the workpiece. The results also emphasize that the dielectric medium has a viscosity (8.6 CS) higher than EDM oil (2.16 CS) is helpful for higher MRR. The debris particle has remained suspended in the dielectric medium due to its highly viscous properties leading to high MRR without any flushing technique. The process parameters, pulse-on-time, and peak current have dramatically influenced the EDM process. Further, the surface morphology has also been investigated. Results have also revealed that at a low peak current value, the MRR has increased by 155.55%, whereas, at a low value of pulse-on-time, MRR has decreased by 28.25%. At a high peak current value, MRR has increased by 217.55%, whereas, at a high value of pulse-on-time, MRR has increased by 324.05%. The highly carbonated liquid dielectric has considered the most suitable dielectric medium for high discharge energy. Micro-crack density and size have increased with MRR because of highly concentrated discharge energy. The recast layer thickness has increased with the dielectric medium's viscosity because of improper molten metal flushing, and the molten metal re-solidifies on the same surface. [ABSTRACT FROM AUTHOR]

The as-cast Al-4.6Mg alloy was subjected to deformation and sensitization–desensitization heat treatment, and then the microstructure and the enhancement mechanism of Sr were investigated by optical microscopy, scanning electron microscopy–energy-dispersive spectroscopy, electron backscatter diffraction, and transmission electron microscopy. The precipitation phases of Al-4.6Mg alloy were mainly β-Al3Mg2, Al6Mn, and Al6(Mn Cr), and the nanoscale precipitation phases were Al3Mn and Al11Mn4. The formation of β-Al3Mg2 was hindered by the addition of 0.1 wt.% Sr. In addition, the precipitate phase Al4Sr and the nano-sized precipitate phase τ-Al38Mg58Sr4 were uniformly distributed in the spherical matrix. The addition of Sr promoted the redissolution of Mg atoms in Al-4.6Mg alloy, increasing the solubility of Mg in the α-Al matrix from 4.7 wt.% to 5.1 wt.%. The microstructure analysis showed that Sr addition inhibited the recovery and recrystallization of the alloy because the Sr element elevated the recrystallization temperature. As a result, the grain deformation was intensified, the grain size was decreased from 6.96 μm to 5.39 μm, the low-angle grain boundaries were increased from 78.7 at % to 84.6 at %, and the high-angle grain boundaries were increased from 21.3 at % to 15.4 at %. Furthermore, the mechanical properties of the alloy were significantly improved, and the plasticity degraded after the addition of the Sr element. The yield strength of the alloy was enhanced mainly through fine grain strengthening, dispersion strengthening, solid solution strengthening, and working hardening. The strengthening mechanisms were analyzed in detail. [ABSTRACT FROM AUTHOR]

The samples of precipitated tin (IV) phosphate, modified using hydrothermal, microwave, and mechanochemical procedures, were studied in the process of Cs(I), Sr(II), and U(VI) ion sorption. The initial and modified samples were investigated before and after sorption using XRD, XRF, FTIR, and nitrogen adsorption–desorption. It was found that the modification procedures transformed the micro-mesoporous structure of the initial sample into a meso–macroporous structure. As a result, the sorption capacity in relation to all ions increases several times. This indicates the determining role of the porous structure, primary content, and mesopore size on the sorption activity of tin phosphate. The samples, treated in the form of a wet gel, which is a novel procedure, showed the maximum sorption indicators. The sorption of all the tested ions is described by the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

This paper describes the sequential separation of actinides such as U, Pu, Am, and Sr in urine samples. Urine bioassay is one of the preferred methods for assessing low level of internal contamination in radiation workers. Any special monitoring case necessitates the completion of sample analysis as soon as possible. Hence, in this work, efforts have been made to reduce the overall analysis time for the estimation of actinides and strontium in urine samples. In the described method, TRU and Sr-spec resins are used in tandem for the separation of actinides and strontium. The proposed method is very convenient to handle, rapid, and robust when compared with ion exchange and other extraction chromatography work. Radiochemical recoveries of 232U, 242Pu, 243Am, and 90Sr obtained are in the range of 66%-89%, 63%-99%, 63%-96%, and 61%-79% with an average and standard deviation of 77.2% ±7.2, 79.8% ±11.4, 80.9% ±11.2, and 71.8% ±5.9, respectively. [ABSTRACT FROM AUTHOR]

The impact of the climate drying during the Holocene within the Nile River Valley System (NRVS) has been the focus of recent debate in the archaeological community. It is argued that the increased contribution of aeolian material from the neighboring Sahara Desert during the last ~7,000 years has changed the isotope compositions of bioavailable Sr relative to the geological background and thus hinders provenance investigations of human remains within the NRVS. This study reports new trace element and strontium (Sr), neodymium (Nd), and lead (Pb) isotope compositions for a combined total of 125 samples consisting of human tooth enamel and various faunal samples from different time periods, and present-day botanical samples from 11 archaeological sites along the NRVS. The new isotope data combined with published data do not support a time-dependent increase in a Saharan aeolian bioavailable Sr component during the Holocene within the NRVS; in general, Sr isotope compositions for human enamel samples match those of their corresponding faunal matrices, and these define a similar range of isotope compositions over the various time periods. The Nd and Pb isotope compositions for human tooth enamel reported here also support the limited contribution of Saharan aeolian dust within the NVRS. [ABSTRACT FROM AUTHOR]

Twelve apatite samples have been tested as secondary ion mass spectrometry (SIMS) reference materials. Laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) analysis shows that the SLAP, NUAN and GR40 apatite gems are internally homogeneous, with most trace element mass fractions having 2 standard deviations (2s) ≤ 2.0%. BR2, BR5, OL2, AFG2 and AFB1, which have U > 63 μg g‐1, 206Pb/204Pb > 283, and homogeneous SIMS U‐Pb data, have respective isotope dilution thermal ionisation mass spectrometry (ID‐TIMS) ages of 2053.83 ± 0.21 Ma, 2040.34 ± 0.09 Ma, 868.87 ± 0.25 Ma, 478.71 ± 0.22 Ma and 473.25 ± 0.09 Ma. Minor U‐Pb heterogeneity exists and accurate SIMS results require correction with the 3D Concordia‐constrained common Pb composition. Among the studied samples, AFG2 and BR5 are the most homogeneous U‐Pb reference materials. The SIMS sulfur isotopic compositions of eight of the apatites shows they are homogeneous, with 2s for both 103δ34S and 103δ33S < 0.55‰. One apatite, BR96, has Δ33S = ‐0.36 ± 0.2‰. The apatite samples have ID‐TIMS 87Sr/86Sr between 0.704214 ± 0.000030 and 0.723134 ± 0.000035. [ABSTRACT FROM AUTHOR]

The technique of integrating images from two or more sensors that were taken from the same place or the same object is known as image fusion. The goal is to get more spectral and spatial information from the combined image as a whole than from the individual images. It is required to fuse the images in order to improve the spatial and spectral quality of both panchromatic and multispectral images. This study introduces a novel method for fusing remote sensing images that combines L0 smoothing, NSCT (Non-subsampled Contourlet Transform), SR (Sparse Representation), and MAR (Max absolute rule). The multispectral and panchromatic images are initially divided into lower and higher frequency components using the L0 smoothing filter as the method of fusion. The fusion process is then carried out, utilising a technique that combines NSCT and SR to fuse low-frequency components. Similar to this, the Max-absolute fusion rule is used to fuse high-frequency components. In conclusion, the disintegration of fused low-frequency and high-frequency data yields the final image. Our method yields an enhanced outcome in terms of the correlation coefficient, Entropy, spatial frequency, and fusion of mutual information for both the term of picture quality enhancement and visual evaluation. This suggested approach produces superior outcomes after execution. This study makes use of the Landsat-7ETM+, IKONOS, and Quick Bird datasets. Different satellites are used to take each image. There have been two examples of each image used. In comparison to previous Traditional Methods, the proposed image fusion techniques' output has a quality that is more than 20% higher. [ABSTRACT FROM AUTHOR]

We present newly acquired data on the trace element composition and Sr–Nd–Pb-O isotopes of Pliocene – Holocene basalts of the Medvezhiy caldera located on the Iturup Island, Kuril arc. With its unique rhenium mineralization and high-Mg basalt volcanism, it is the largest caldera on the volcanic front of the Kurile Island arc. The calc-alkaline suite of rocks spanning the range from high-Mg basalts to high-Al basalts, has typical arc rock features, such as Nb-Ta depletion and LILE enrichment. The whole set of the caldera geochemical data is divided into two age units, pre- and postcaldera basalts. The precaldera basalts typify low-K, high-Al, basaltic suite of the frontal zones of «cold» subduction. PRIMACALC2 code and Arc Basalt Simulator version 3.1 forward model points to ~21.7% of partial melting of moderately depleted mantle peridotite with relatively high water content (~0.34 wt%) at the pressure of ~1.37 GPa. With similar isotope and trace element signatures, Late Pleistocene–Holocene basalts are marked by the high abundances of MgO (up to 11 wt %), but low Al2O3. The primary magmas were generated from depleted mantle with lower H2O content (~0.13%) and degree of partial melting (~9.5%), but at higher pressure (~1.77 GPa). The decompression scheme reproduces the fractionation trends of postcaldera magnesian basalts for most major elements but fails to explain the composition variations of the precaldera lavas. Their origin has been the matter of some complex processes in the shallow magma chamber. The abrupt change in the type of eruptions and magma composition of the caldera in Late Pleistocene–Holocene were related to a transformation of both the magma-feeding and melt generation systems as the result of geodynamic reorganization of the vast territory adjacent to the Sea of Japan and Kamchatka. [ABSTRACT FROM AUTHOR]

Cardiac calcium alternans is defined as beat-to-beat alternations of Ca transient (CaT) amplitude and has been linked to cardiac arrhythmia, including atrial fibrillation. We investigated the mechanism of atrial alternans in isolated rabbit atrial myocytes using high-resolution line scan confocal Ca imaging. Alternans was induced by increasing the pacing frequency until stable alternans was observed (1.6–2.5 Hz at room temperature). In atrial myocytes, action potential-induced Ca release is initiated in the cell periphery and subsequently propagates towards the cell center by Ca-induced Ca release (CICR) in a Ca wave-like fashion, driven by the newly identified 'fire-diffuse-uptake-fire' (FDUF) mechanism. The development of CaT alternans was accompanied by characteristic changes of the spatio-temporal organization of the CaT. During the later phase of the CaT, central [Ca]i exceeded peripheral [Ca]i that was indicative of a reversal of the subcellular [Ca]i gradient from centripetal to centrifugal. This gradient reversal resulted in a reversal of CICR propagation, causing a secondary Ca release during the large-amplitude alternans CaT, thereby prolonging the CaT, enhancing Ca-release refractoriness and reducing Ca release on the subsequent beat, thus enhancing the degree of CaT alternans. Here, we propose the 'reverse FDUF' mechanism as a novel cellular mechanism of atrial CaT alternans, which explains how the uncoupling of central from peripheral Ca release leads to the reversal of propagating CICR and to alternans. [ABSTRACT FROM AUTHOR]

BACKGROUND: Uranium - series nuclides are one of the three major radioactive decay systems, which are suitable for studying various geological processes at different time scales. In addition, 87 Sr/ 86 Sr and 143Nd / 144Nd isotopes ( Sr - Nd isotopes for short) are two commonly used isotopes, for rock dating, chemical weathering assessment and tracing sediment sources. In this case, the combination of Sr -Nd -U isotopes can provide more comprehensively knowledge of the element cycle on the earth’ s surface and deepen our understanding of the sediment “Source to Sink”processes. Most previous studies involving the Sr - Nd - U isotopes have been established by separating Sr - Nd and U isotopes respectively. In this way, the digestion operation must be performed twice, one for separating Sr-Nd and the other for separating U. Alternatively, if only one sample is digested for measuring all three isotopes, between each element separation, the residue must be dried and dissolved in another solution so as to start a new column work. The former increases the amount of samples, which is not conducive to analysis of precious and trace samples; the latter adds additional drying operation, which is time consuming and increases the risk of sample loss and contamination. OBJECTIVES: To establish a new Sr-Nd-U combined separation scheme. In this method, only one sample is dissolved, avoiding solution transfer between each separation, so as to reduce sample amount and improve the efficiency of separation and purification of Sr-Nd-U isotopes. METHODS: A new chromatographic scheme of separating Sr-Nd-U with one sample digestion using a tandem column scheme is presented. Three columns were overlain sequentially to separate Sr in Sr Spec column, Nd in AG50W-X8 column and U in UTEVA column. 3mol / L HNO3 was used to pre-condition, load the sample, and rinse the matrix. After rinsing the matrix, the tandem column was separated to 3 independent columns to elute the target elements (Sr, Nd, U) respectively. As the connection sequence of different resin columns may interfere with the recovery of target elements, two different chromatographic schemes were compared. In Scheme 1, U column was placed on top of Sr column, while in Scheme 2 the positions of U column and Sr resin column were exchanged. In both schemes, the AG50W-X8 resin column was set at the bottom as the cationic resin can adsorb the most complex elements. All separated elution was tested for element concentration using inductively coupled plasma-mass spectrometry ( ICP-MS). The basalt standard sample (BCR-2) was used to examine the behavior and recovery of each element in the separation procedure. RESULTS: A total of 10 fractions were recovered from the tandem column scheme, among which fraction 1 represented the leachate recovered by loading samples and rinsing matrix from the tandem three columns. Fraction 2, 5 and 8 represented the leachate recovered by Sr Spec resin, AG50W-X8 resin and UTEVA resin respectively rinsing matrix after separation of the three columns. Fraction 3, 6 and 9 represented the leachate recovered by Sr, REE and U columns, which was Sr, Nd and U collection. Fraction 4, 7 and 10 represented the leachate from each resin recycle stage. In either Scheme 1 or Scheme 2, most matrix elements (high content of K, Ca, Na, Mg, Al, Fe, Ti and P and low content of Rb, Hf and Th) were mainly concentrated in fraction 1. The elution rate of Na, Ti, Rb and Hf was up to 99%. The elution rate of K and Ca was slightly lower at about 85% and the elution rate of Fe was about 56%. Sr was mainly concentrated in fraction 3, which contained only a small amount of P and Ba. Nd was mainly concentrated in fraction 6, which also contained both Sm and Ce. U was mainly concentrated in fraction 9, which only contained a very small amount of P and Pb. The column recovery was almost 99. 9% for U, 90% for Sr and over 80% for Nd. The removal rate of major matrix elements (K,Ca, Na, Ba, Fe, Rb, etc. ) exceeded 99%, which reduced interference with high-precision isotope analysis of Sr, Nd, and U. The recovery and purity of Sr, Nd, U were all quite high. A very small amount of P and Ba in fraction 3 had no interference with Sr isotopes ( 87 Sr/ 86 Sr). The Rb which was isomorphism of Sr was removed completely. With regard to Sm and Ce in fraction 6, previous studies had shown that 142Ce could not interfere with Nd isotope ( 143Nd / 144Nd), and Sm could be further separated by Ln resin, so as not to affect Nd isotopic test. Fraction 9 contained nearly 100% U with no other elements. The sequence of resin column splicing is a crucial consideration which may impact the element separation. Hence, the position of Sr Spec column and UTEVA column was exchanged to compare the influence of different column sequences on eluting target elements. Both Scheme 1 and Scheme 2 can effectively wash off most of the matrix elements, and the target elements Sr, Nd and U can be efficiently adsorbed on the resin. There is no significant difference on target element separation between the two different column sequences. This indicates that Sr Spec and UTEVA resins do not interfere with each other on the target elements. CONCLUSIONS: The new chromatographic scheme of separating Sr -Nd -U with one sample digestion using a tandem column scheme can be used to quickly and efficiently separate Sr, Nd and U elements from silicate rock samples. The recovery rate for U, Sr and Nd is 99. 9%, 92. 5% and 82. 1%, respectively, which meet the requirements of subsequent isotope analysis. This Sr-Nd-U combined separation method can be used to reduce the sample consumption by about 50%, which is beneficial to the analysis of precious and trace samples. Meanwhile, as no solution transfer is needed between each column separation, this method can also save time for column work and increase the efficiency of chemical separation. A new idea for Sr-Nd-U multi-isotope separation is provided. If the recovery of Pb in the fraction 4 of this chromatographic scheme can be improved in further studies, the application of this new method may be expanded to more fields in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Strong fixation of Sr, U, and Pu in river bottom sediments can occur under conditions of sufficiently high N, P, S concentrations. In consequence, this environment facilitates active phytoplankton growth and the formation of biogenic minerals. These conditions can be achieved by adding the necessary nutritive components to the water and bottom sediments of polluted water bodies. Laboratory modeling of Cs, Sr, U, Pu immobilization by phytoplankton of the river Upa, affected after the Chernobyl accident, has been carried out. Certain conditions are selected for strong fixation of radionuclides in bottom sediments due to biogeochemical processes. The process of radionuclide removal from the water phase via precipitation was based on their accumulation by phytoplankton, stimulated by nitrogen and phosphorus sources. After eight days of stimulation, planktonic phototrophic biomass, dominated by cyanobacteria of the genus Planktothrix, appears in the water sample. The effectiveness of U, Pu and Sr purification via their transfer to bottom sediment was observed within one month. The addition of ammonium sulfate and phosphate (Ammophos) led to the activation of sulfate- and iron-reducing bacteria of the genera Desulfobacterota, Desulfotomaculum, Desulfosporomusa, Desulfosporosinus, Thermodesulfobium, Thiomonas, Thiobacillus, Sulfuritallea, Pseudomonas, which form sulphide ferrous precipitates such as pyrite, wurtzite, hydrotroillite, etc., in anaerobic bottom sediments. The biogenic mineral composition of the sediments obtained under laboratory conditions was verified via thermodynamic modeling. [ABSTRACT FROM AUTHOR]

Higher accuracy and precision are highly demandable in modern industry through computer-aided manufacturing technology. The paper deals with the parametric analysis for helix angle(°), radial depth of cut (mm), axial depth of cut (mm) and cutting speed(m/min) as well as the second-order mathematical modelling for Surface Roughness (SR) as surface texture (Ra ), Tool Wear Rate (TWR) and machining rate as a form of Material Removal Rate (MRR) have been carried out. Analysis of Variances (ANOVA) is performed during helical profile cutting on cast iron based on modelling. Multi-response, as well as single objective optimization, has been done for finding the best process parameters setting for maximum MRR and minimum TWR and SR using desirability function analysis during profile cutting by advanced CNC milling. It is found that surface finish accuracy is increased with better surface quality and lower tool wear found with maximized MRR using AlTiN (aluminium titanium nitride) coated Tungsten carbide Tool (WC). [ABSTRACT FROM AUTHOR]

In this paper, the copper (Cu)-based multi-wall carbon nanotube (MWCNT) composite tools were fabricated using electro-co-deposition method. The composite tools were prepared from different MWCNT concentrated (0.5, 0.75 and 1 g/L) electrolytic solution and these tools were utilized in electro discharge machining (EDM). The experiments were performed with varying discharge currents. The results indicated that the incorporation of MWCNTs into the copper matrix greatly influenced the machining performances. A lower rate of tool wear and higher material removal rate (MRR) were observed for the copper-based MWCNT composite tools at different discharge currents. The highest tool wear rate (TWR) was reduced by 45.68% and the MRR was improved by 63% for the Cu-MWCNT (0.5 g/L) composite tool compared to copper coated tool. At higher discharge current, smoother machined surfaces were generated using copper-based MWCNT composite tools compared to the copper tools. The SEM image exhibits that the micro-crack-free machined surfaces were produced by using copper-based MWCNT composite tools. The migration of tool material to the machined surface was also reduced for copper-based MWCNT composite tools. [ABSTRACT FROM AUTHOR]

The substituted (Ca2+/Cu2+), and co-substituted (Cu2+/Zn2+), (Cu2+/Sr2+), and (Sr2+/Mn2+) β-tricalcium phosphate (β-TCP)-based Ca 3-2 x (MˊMˊˊ) x (PO 4) 2 (M = Zn2+, Cu2+, Mn2+ and Sr2+) solid solutions have been synthesized using solid-state route. The powder X-ray diffraction study shows the formation of β-TCP-type structure as the main phase in all solid solutions. The crystal structures and chemical compositions were approved using Fourier-transform infrared (FT-IR) absorption spectra and energy-dispersive X-ray spectrometry (EDX) data, respectively. The unit cell parameters and volume of as-synthesized samples directly depend on the radius of the incorporated ions. The limits of the single-phase solid solutions were found based on the possible occupation of the crystal sites in β-TCP structure. For the divalent ions with small radii, such as Cu2+ or Zn2+, the limit composition was found as Ca 2.571 Mˊ 0.429– x Mˊˊ x (PO 4) 2 for Mˊ and Mˊˊ – Cu2+ and Zn2+. The enlargement of the unit cell by incorporation of Sr2+ allows to extend the limit of solid solutions up to Ca 2.5 Sr 0.5– x Mˊ x (PO 4) 2 for Mˊ – Cu2+ or Mn2+. The antibacterial properties were studied on 4 bacteria (S. aureus, P. aeruginosa, E. coli and E. faecalis) and 1 fungus (C. albicans). It has been showed that co-doped Ca 2.5 Sr 0.25 Cu 0.25 (PO 4) 2 sample exhibits the highest antimicrobial activity resulting in 92%, 96% and 96% inhibition growth rate for S. aureus, P. aeruginosa and E. faecalis , respectively. The antimicrobial properties are strongly related to the occupation of the crystal sites in the β-TCP structure by doping ions. [ABSTRACT FROM AUTHOR]

Throughout the world, cancer is the top cause of mortality in women. Whatever improvement in cancer ailment identification and prognosis is vital to living a healthy life. As a consequence, excellent cancer prediction accuracy is crucial for maintaining treatment and survival criteria current for patients. Machine learning techniques, which have been found to have a major impact on the identification and early treatment of breast cancer, have emerged as a hotspot for study and have been demonstrated to be a potent methodology. We used five machine learning algorithms in this research. There have been various empirical investigations employing machine learning and soft computing techniques to treat breast cancer. This article provides an overview of the available technologies for advanced treatment of breast cancer, as well as an introduction to the concepts and current achievements in personalised medicine that depend on technology. The many kinds of breast cancer are addressed, as well as their worldwide occurrence. It is discussed the importance of recognising irregularities and distinguishing between benign and malignant breast cancer. Levenberg-Marquardt (LM) and Sparse Representation (SR) have been combined to model a new approach for diagnosing breast cancer. With LM's training accuracy and SR's robustness in identifying small deformations, an impressive performance was achieved in terms of accuracy and mean square error. Data has been acquired from the Wisconsin Dataset (WD). This model proves the combination of several classification algorithms could enhance the model in a significant manner and can be used for pre-clinical diagnosis. [ABSTRACT FROM AUTHOR]

Fusarium keratoplasticum is the Fusarium species most commonly associated with human infections (fusariosis). Antifungal treatment of fusariosis is often hampered by limited treatment options due to resistance towards azole antifungals. The mechanisms of antifungal resistance and sterol biosynthesis in fusaria are poorly understood. Therefore, in this study we assessed the transcriptional response of F. keratoplasticum when exposed to voriconazole. Our results revealed a group of dramatically upregulated ergosterol biosynthesis gene duplicates, most notably erg6A (912-fold), cyp51A (52-fold) and ebp1 (20-fold), which are likely part of an alternative ergosterol biosynthesis salvage pathway. The presence of human cholesterol biosynthesis gene homologs in F. keratoplasticum (ebp1, dhcr7 and dhcr24_1, dhcr24_2 and dhcr24_3) suggests that additional sterol biosynthesis pathways may be induced in fusaria under other growth conditions or during host invasion. Voriconazole also induced the expression of a number of ABC efflux pumps. Further investigations suggested that the highly conserved master regulator of ergosterol biosynthesis, FkSR, and the pleiotropic drug resistance network that induces zinc-cluster transcription factor FkAtrR coordinate the response of FSSC species to azole antifungal exposure. In-depth genome mining also helped clarify the ergosterol biosynthesis pathways of moulds and provided a better understanding of antifungal drug resistance mechanisms in fusaria. [ABSTRACT FROM AUTHOR]

Some metals are necessary nutrients for plant health while some are toxic pollutants. In this study, the ability of Croton lindheimeri to uptake essential element Fe or toxic metal Sr was assessed separately. The amounts of iron plaque on the root systems and the levels of Fe in C. lindheimeri collected from an iron-rich field were assessed. The results indicated that Translocation Factor (TF) of Fe in C. lindheimeri was around 1, with similar amounts of Fe in roots and shoots. C. lindheimeri seedlings were cultured in Sr solutions for 3 weeks to determine its potential to accumulate Sr. It was found that the roots of C. lindheimeri cultured in 20 mg/L Sr solutions sequestered 0.05 ± 0.01 mg Sr/g biomass. TF of Sr in C. lindheimeri was >1. Further research is worthwhile to evaluate the potential of C. lindheimeri to remediate Sr contaminated sites. Novelty statement No study related to the sequester of metals (either essential or non-essential metals) in Croton lindheimeri (goat weed) was found before. It was the first research about metal accumulation in goat weed. Fe plaque formation and iron sequester in the biomass of Croton lindheimeri were never studied in previous research. Very limited information about phytoremediation of Sr contaminated media was reported in previous studies, this study filled the gap by exploring the uptake of Sr in Croton lindheimeri. [ABSTRACT FROM AUTHOR]

In order to investigate the optimum refinement and modification scheme of the new low-silicon cast aluminum alloy, experiments were carried out on macroscopic grain size statistics, eutectic silicon phase morphology observation and tensile properties test for aluminum alloys with different contents of Al-3B refiner and Al-10Sr modifier. The results showed that when the amount of B added in the low-silicon cast aluminum alloy was 200 ppm, the AlB2 particle which can act as the ideal substrate for grain nucleation in the alloy can be saturated, and the alloy was distributed with fine uniform equiaxed grains while the grain size was minimised. Moreover, when the amount of Sr addition was 250 ppm, the eutectic silicon can exhibit a branched and dense coral branch because the Sr in free form was sufficiently adsorbed on the eutectic silicon. The effect of SrB6 formed by the interaction between Sr and B was the smallest. The alloy exhibited a uniform distribution of fine round grains after heat treatment, and obtained the optimum comprehensive mechanical properties. And the tensile strength reached 370.3 MPa, the yield strength was 307.3 MPa, and the elongation increased to 8.3%. [ABSTRACT FROM AUTHOR]

The Wenjiaping granite, as one of the few Late Jurassic granites in the Songpan–Garzê fold belt (SGFB), can provide an important clue for comprehensively recognizing the tectonic evolution and mineralization of this belt. In this contribution, we present new age and geochemical data for this pluton to better constrain its petrogenesis and discuss the tectonic and metallogenic implications. LA‐ICP‐MS zircon U–Pb dating shows that the Wenjiaping pluton was emplaced at ~159 Ma. The granite contains minor amphibole, and exhibits slightly peraluminous characteristics (A/CNK = 1.03–1.10) and lower initial Sr–Pb isotope ratios than those of the Liwu Group, which excludes the possibility that the Wenjiaping granite was derived from partial melting of the metasedimentary rock‐dominated Liwu Group as previously suggested. Significantly, high Sr/Y (40.93–54.30), LaN/YbN (39.64–56.64), and K2O/NaO (0.77–1.11) ratios, low MgO (0.47%–0.86%) and Cr (25.1–41.3 ppm) contents, and relatively enriched Sr–Nd–Pb–Hf isotope compositions of the Wenjiaping granite are comparable to those of the Late Triassic adakitic rocks in the SGFB, indicating that they probably share a similar source. Combined with previous researches, we propose that large‐scale detachment of the Jianglang dome caused by post‐collisional lithospheric extension in the SGFB‐induced decompressional partial melting of the Precambrian basement rocks can account for the generation of the Late Jurassic Wenjiaping pluton. In addition, our results also suggest that the Wenjiaping pluton probably cannot supply abundant metal elements for the Liwu‐type Cu‐polymetallic deposits in the Jianglang dome, SGFB. [ABSTRACT FROM AUTHOR]

The Eastern Mongolian Volcanic Area (EMVA) is part of the Late Mesozoic–Early Cenozoic volcanic and plutonic belt in Northeastern Asia. The EMVA evolved in three stages, with volcanic rocks of different composition produced during each of the stages and with the parental melts of the rocks derived from different sources and formed by different mechanisms. The rocks of the Early Cretaceous stage (135–100 Ma), which form the volcanic flow complex of the EMVA, are predominantly differentiated alkali basaltoids. Data on isotopic features of these rocks, particularly their Pb isotope composition, allowed us to identify the nature of their sources: peridotites of the Continental Metasomatized Lithospheric Mantle (CMLM) and lower continental crustal eclogitic rocks. The alkali basaltoids of the extrusive complex of the Uldza-gol volcanic field were formed during the next evolution stage of the EMVA at 104–90 Ma. According to their geochemical and isotope features, the melts of these rocks were derived from the same sources as those of the volcanics of the previous Early Cretaceous stage, except only that eclogite material played a more significant role in forming of the Uldza-gol basaltoid melts. During the concluding stage of the EMVA evolution in the Late Cretaceous–Early Cenozoic (87–51 Ma), OIB-like rocks of the basanite–trachybasalt association were formed in the Central Gobi in the southwestern flank of the EMVA. Asthenospheric and recycled pyroxenite components, together with not so much CMLM peridotites, were involved in forming of these rocks. The various sources of the EMVA volcanic rocks reflect two mechanisms of their formation. In the Early to Late Cretaceous, magmatism was triggered by the ascent of the asthenospheric mantle and delamination of the lithospheric mantle, whereas the Early Cenozoic magmatism was induced by the activity of a mantle plume. [ABSTRACT FROM AUTHOR]

This research was carried out in Antoniadis Garden, Alexandria city, Egypt, on trees of fourteen genera belong to family fabaceae, to study the differences on their leaves spectral properties, using some vegetation indices "NDVI, SR, IR/R, IR/G, RE, REP and DN". Also, spectral reflectance curve of each tree species and for each and both leaf surface was drawn to examine the ability of spectral measurements and vegetation indices to differentiate among tree species. Moreover, leaves content of total chlorophyll was determined and it's correlation to studied indices was examined. Results showed that all studied indices can successfully differentiate among trees species and showed a highly significant differences between species. Moreover, spectral curve of each plant species were obviously separated for each and both leaf surface. It is manifested that Green and NIR regions are clearly separated between spectral curves of leaves according to their color, thickness and internal structure, so this electro-magnetic radiation of light can be used successfully to classify plant species. Also, a highly correlation was found between total chlorophyll content and studied vegetation indices. [ABSTRACT FROM AUTHOR]

Titanium alloys have exceptional mechanical properties together with high strength to weight ratio and have widespread applications in the aerospace sector. Generally, these alloys have drawback with machinability. Wire-Electro Discharge Machining (WEDM) is in use to make complex shapes. Titanium alloy efficient machining includes choosing appropriate process parameters to optimize the performance characteristics. The present experimental investigation deals with process optimization of Wire Electro Discharge Machining (WEDM) process on Titanium grade 5 material using brass wire of 0.25 mm. Servo Voltage, Peak current, Pulse-on-time and Pulse-off-time, are considered as input parameters. Experiments are carried out utilizing Taguchi's L27 orthogonal array. Every process parameter is analyzed at 3 levels by using Grey Relational Analysis (GRA). The finest process parameters that optimize the Wire Wear Ratio (WWR) and Surface Roughness (SR) are identified. ANOVA is accomplished to estimate the significance of all input parameters on output performance characteristics. Confirmation tests are conducted. Experimental results are in acceptable concurrence with the confirmation test values. [ABSTRACT FROM AUTHOR]

A leach resistant, stable strontium (Sr) specific solid phase ion exchange material that could be used as a matrix for immobilizing Sr-bearing nuclear waste was developed, and different studies were conducted to establish the material's stability. Sodium copper titanate (SCT) that was prepared by a simple solution synthesis method exhibited a high Sr removal tendency from pH 4 to 8, and is therefore capable of removing Sr from alkaline aqueous waste in the pH range. Sr adsorption was modeled using Langmuir, Freaundlich, Tempkin, and D-R isotherm models and the diffusion based reaction kinetics models have also been explored by modeling adsorption kinetics. Subsequent to Sr exchange to SCT at room temperature, the material was calcined at 673 K and 1273 K. Material stability of the Sr loaded SCT matrix was studied using thermogravimetric, SEM, X-ray diffraction and Raman spectrometric methods. Soxhlet leaching experiments were performed on the Sr-loaded SCT established the stability of the studied material under harsh conditions. A newly prepared inorganic ion exchange material, sodium copper titanate, demonstrated exemplary selectiveness for strontium compared to cesium, proving to be a suitable ceramic material for use as a nuclear waste immobilization matrix. Studies on Soxhlet leaching, phase change characterization by XRD, and matrix stability by TGA, DSC, along with additional characterization by Raman and SEM, support this conclusion. Furthermore, adsorption experiments for strontium and their modeling using different models also corroborate these findings. [Display omitted] • Highly stable and leach resistant sodium copper titanate based ion exchanger for immobilizing Strontium. • High Sr removal tendency from pH 4 and above. • Sr adsorption was modeled using different isotherm models, diffusion and reaction kinetics models. • Soxhlet leaching experiments to study stability of the studied material under harsh conditions. • Sr loaded ion exchanger was characterized using thermogravimetric, X-ray diffraction, SEM and Raman spectrometric methods. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of the timing of selective reduction and finishing the number of fetuses on perinatal outcomes in triplets. The study assessed 417 cases of triplets. Perinatal outcomes were compared between selective reduction (SR) performed at 11–14+6 weeks of gestation and SR performed at 15–24+6 weeks of gestation for the same starting and finishing numbers of fetuses. Then, the perinatal outcomes of reduction to singletons and twins were compared for the same range of SR of gestational weeks. The spontaneous abortion rate was 6.5% and 14.9%, respectively, when SR was performed at 11–14+6 weeks of gestation (214 cases) and at 15–24+6 weeks of gestation (94 cases) (p =.019). In total, 74 cases of triplets were reduced to singletons and 214 cases were reduced to twins when SR was performed at 11–14+6 weeks of gestation. Preterm labor rates, low birth weight rates, birth weights, and gestational ages at delivery also showed significant differences (p <.001). In total, 35 cases of triplets were reduced to singletons and 94 cases were reduced to twins when SR was performed at 15–24+6 weeks of gestation. The preterm labor rates, low birth weight rates, birth weights and gestational ages at delivery also significantly differed (p <.05). When the starting and finishing numbers of fetuses were the same, the timing of SR could affect the spontaneous abortion rates. When the starting number of fetuses was the same, the timing of SR did not affect the neonatal outcome. However, the finishing number of fetuses was the influencing factor. [ABSTRACT FROM AUTHOR]

Plasma-sprayed hydroxyapatite (HAp) coated metallic implants for orthopaedic and dental application have some inherent shortcomings like brittleness, low fracture toughness, poor tensile strength, slow osseointegration rate and poor antimicrobial properties. To mitigate these shortcomings, we have envisaged and developed specific compositions of Sr, Zn, Ag and F multi-ion doped HAp earlier employing Taguchi statistical principle. The aim of the present investigation is to study the feasibility of plasma spray-coated metallic implants focusing specifically on two specific compositions {based on Sr–Zn–F-HAp – (D1HAp-Ti) and Sr–Zn–Ag-HAp (D2HAp-Ti)} as envisaged earlier. Performance of the above compositions was studied and compared with no coating and pure HAp coated implants. The comprehensive study included detailed material development and characterization up to in vivo pre-clinical trial. Finally, free-flowing granules (75–104 μm) of multi-ion doped HAp were used for plasma spray coating on Ti6Al4V substrate and analyzed the effect of multi-ion doping on HAp. Interestingly, XRD showed presence of HAp as main phase in all cases except undoped HAp coating where secondary phases like α-TCP and β-TCP could also be traced. FTIR study confirmed basic functional groups of HAp for all cases. Scratch adhesion of coating as well as microhardness was found to be increased substantially by multi-ion doping The result from corrosion resistance and SBF immersion test clearly exhibited multi-ion doped HAp coated implant's superior property co over undoped HAp coating. In vivo implantation of these implants in animal femur defect model and follow up investigation up to 2 months with micro-CT, histology, radiology and fluorochrome labelling showed enhanced osseointegration of multi-ion doped samples as compared to bare, and control samples.. Hence, a multi-ion doped HAp coated titanium substrate can be used as a promising implant coating material for orthopaedic applications. [ABSTRACT FROM AUTHOR]

Fluid flow and carbonate recrystallization rates of deep-sea sediments from eight locations in the Equatorial Eastern Pacific were determined by using δ44/40Ca values of pore water and corresponding sediments. The studied drill sites of IODP Exp. 320/321 are located along a transect of decreasing crustal age and reveal different characteristic pore water depth profiles. The younger sites show an overall isotopic equilibration with the sediment in the upper part of the sedimentary column. In the lower part, the δ44/40Ca of the pore water increases back to seawater-like values at the sediment/basalt interface, forming a bulge-shaped pore water profile. The magnitude of the δ44/40Ca pore water bulge decreases with increasing age of the oceanic crust and sediment cover, resulting in seawater-like δ44/40Ca values throughout the sedimentary column in the oldest Sites U1331 and U1332. These findings indicate a seawater-like fluid input from the underlying crust into the sediment. Thus, after sedimentation, carbonate recrystallization processes start to enrich the pore water in 40Ca, and after a time of carbonate recrystallization and cooling of oceanic crust, a flow of seawater-like fluid starts to move upwards through the sedimentary column, enriching the pore water with 44Ca. We established a carbonate recrystallization and fluid flow model to quantify these processes. Our determined carbonate recrystallization rates between 0.000013e(−t/15.5) and 0.00038e(−t/100.5) and fluid flow rates in the range of 0.42–19 m*Myr−1 indicate that the fluid flow within the investigated sites of IODP Exp. 320/321 depends on the sedimentary composition and location of the specific site, especially the proximity to a recharge or discharge site of a hydrothermal convection cell. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is the unconventional machining technique used extensively for machining difficult-to-machine materials with lower material removal rate and poor surface roughness. To overcome these drawbacks, synthetic dielectric fluid is replaced with nanoparticle-infused biodegradable dielectric fluid in the machining of Hastelloy material. This paper focusses on the machining performances of Hastelloy in EDM using various concentrations of 0.5, 1 and 1.5 wt% of nano-zirconia dispersed in biodegradable canola oil methyl ester as the dielectric medium, and these characteristics were compared with those of the synthetic dielectric medium. Based on the D-optimal design coupled with cuckoo search algorithm, machining was carried out with various dielectric fluids and their influences on the metal removal rate, surface roughness, surface morphology and surface topography in EDM studied. The results proved that the canola oil methyl ester containing 0.5 wt% of nano-zirconia (C-0.5) had provided good surface finish, better surface topography, smooth surface morphology and high metal removal rate in comparison with the other dielectric fluids used in this study. [ABSTRACT FROM AUTHOR]

CP-Ti-G2 (Commercially pure titanium grade-2) has become the preferred biocompatible material for various devices mainly used in orthopedic and dental implants and it is also used in aviation and aircraft. While CP-Ti deals with good ductility, higher stiffness, and fatigue resistance. The novelty of present research work was to create a rough surface on CP-Ti-G2 through the WEDM process. Further, this rough surface was used in the development of bone marrow cells on it. Propagation and diversity of bone marrow cells were applied in dental implant osteointegration applications. Six WEDM factors were analyzed through the BBD design of the experiment. 54 trial experiments were conducted to observe the MRR and SR output responses. After machining, surface topography was examined through SEM and EDX. ANOVA was applied to analyze the significance of factors. It was observed that POT (pulse on time), POFT (pulse off time), PC (peak current), and SGV (spark gap voltage) are the most significant factors. The WEDM factors have also been significantly deteriorating the microstructure of machined samples remarkably deeper, wider craters, globules of debris, and micro cracks. A multi-objective optimization ‘desirability’ function was applied to obtain the optimal solutions by numerical and supervised machine learning algorithms. They lead to the reflection of parametric machine learning algorithms to surmise about the effectiveness of WEDM process. The results show a good agreement between actual and predicted values. [ABSTRACT FROM AUTHOR]

The structural depression that occupies the Okavango Basin in southern Africa comprises a depo-centre within the intracratonic Kalahari Basin where sediments of the Cenozoic Kalahari Group have accumulated. The Okavango Basin has been formed due to stretching and subsidence at an area of diffused deformation, southwestwards to the main East African Rift System (EARS). Sediments from two full Kalahari Group sequences, located on opposite sides of the Gumare Fault that forms a major fault within the Okavango Basin, were studied to determine their provenance and chronology. Terrestrial Cosmogenic Nuclide (TCN) 26Al/10Be burial dating was used to constrain a chronostratigraphical framework, and Pb, Sr, and Nd isotopic ratios combined with geochemical and sedimentological analyses were applied to track the source areas of the sediments. Results indicate the following sequence of basin filling: (a) Accumulation between ca. 4-3 Ma during which the currently downthrown (southern) block received a mixture of sediments mostly from the Choma-Kalomo, Ghanzi-Chobe, and Damara terranes, and possibly from the Lufilian Belt and/or Karoo basalts during earlier stages of deposition. Simultaneously, the upthrown (northern) block received sediments from more distant Archean sources in the Zimbabwe and/or Kasai cratons, (b) Hiatus in sedimentation occurred at both sites between ca. 3-2 Ma, (c) Sediments on both sides of the Gumare Fault share a similar source (Angolan Shield) with minor distinct contributions to the downthrown block from the Kasai Craton and local sources input to the upthrown block, and (d) Regional distribution of aeolian sand since at least 1 Ma. The change in source areas is attributed to rearrangements of the drainage systems that were probably linked to vertical crustal movements on the margins of the Okavango Basin. The tectonically induced morphodynamics controlled the landscape evolution of the endorheic basin where vast lakes, wetlands and salt pans have developed through time. [ABSTRACT FROM AUTHOR]

Variation in the trace element chemistry of cortical bone microstructure is delineated for interred and non-interred human femora. This was done to investigate the range of element concentrations that might occur within single bones, specifically the original laminar bone and later osteons, and its potential for investigating chemical life histories. To do so, femora were chosen from individuals who experienced quite different ways of life over the past two millennia. The distributions of Sr, Ba, Cu, and Pb, mostly in partial (early) and complete (late) osteons, in cross-sections of proximal femora were characterized through Laser Ablation Inductively Coupled Plasma Mass Spectrometry. Absolute calibrations of these data were obtained using solution Inductively Coupled Plasma Mass Spectrometry on adjacent dissolved bulk samples. Chemical life histories were approximated by classifying bone microstructure into four categories: laminar bone and 1st, 2nd, and 3rd generation osteons. This four-part sequence, on average, charts the temporal dimension of an individual's life. Consistent with recent studies of medieval bones, Sr and Ba are thought to be mainly responsive to diet, presumably related to the consumption of mostly locally produced food, while Cu and Pb do the same for heavy metal exposure often attributable to social status or occupation. No systematic differences in these elements were found between interred and non-interred individuals. The effect of diagenesis on interpretations of life histories based on archaeological bone, therefore, are minimized by plotting element concentrations across cortical bone cross-sections. [ABSTRACT FROM AUTHOR]

Numerous orogenic gold deposits of different age, scale, and mineralization type are located within Northern Transbaikalia. Among them, there is a large group of Early Permian deposits, whose sources and relationships with Late Paleozoic magmatism remain debatable. These issues were solved by the example of the middle-scale (~24 t, Au) Irokinda deposit, localized within the Precambrian rocks of the Baikal–Muya Terrane. 39Ar–40Ar geochronological dating of the ore-hosting altered rocks indicates that hydrothermal–metasomatic process took place about 270 myr ago. Gold mineralization has heterogeneous Pb-, S-, Sr-, and Nd-isotopic characteristics. Variations in the Pb, S, Sr, and Nd isotopic composition of ore and gangue minerals suggest that the mineral-forming components were involved in the hydrothermal system from different sources. Among them, the leading role belonged to the rocks of the Precambrian crust of the Baikal–Muya Terrane. Pb isotopic composition of the second identified source is close to that of the Early Permian alkaline and subalkaline rocks of the Baikal–Muya Terrane. This fact may indicate a genetic relationship between the Irokinda gold mineralization and intraplate alkaline magmatism, which developed in the region simultaneously with ore-forming processes. [ABSTRACT FROM AUTHOR]

The spheroidization of the silicon eutectic phase in aluminum is an important parameter for casting and significantly influences the material properties. Sr has been used for a long time for eutectic modification in aluminum and many researches have been made on this subject. In this study, the effect of holding time after Sr addition on the mechanical properties and eutectic phase modification of the aluminum were investigated. 200 ppm Sr was chosen as the amount of Sr and the holding times were chosen as 20, 40 and 80 minutes. Tensile test was performed for the determination of mechanical properties and ultimate tensile strength and percentage of elongation values were measured. In order to quantify eutectic modification, the length / width (aspect ratio) ratios of eutectic silicon particles were measured. In addition, Bifilm Index of the molten metal was determined with the reduced pressure test (RPT). With the increase in the holding time, an increase in the aspect ratio and in the Bifilm Index was measured. It has been observed that the tensile strength and elongation values have decreased as the holding time has increased. [ABSTRACT FROM AUTHOR]

The enhancement of the surface quality measures is still attracting great research attentions in electrical discharge machining. In the present investigation, an analysis was made to improve the surface performance measures in EDM process with different tool electrodes such as titanium, copper, and graphite electrodes under dielectric medium mixed with micro size titanium particles. The surface roughness, hardness, white layer thickness, crack formation, and surface topography were considered as surface quality measures. From the experimental investigation, it has been observed that surface hardness could be improved significantly with titanium powder-mixed dielectric medium due to its ability of changing conductivity of machining zone with copper tool electrode. The electrical and thermal conductivity of tool electrode and powder materials can strongly affect the quality of the machined surface in EDM process. [ABSTRACT FROM AUTHOR]

Dielectrical fluids have substantial impact on the machining performance of electrical discharge machining (EDM). Apposite selection of these fluids enhances the material removal rate (MRR) and microhardness while abating the tool wear rate (TWR) and surface roughness. In the present research, feasibility of using cerium oxide/water (CeO2/water) dielectrical nanofluid in EDM is examined experimentally. A portable EDM has been employed for experimental test, whereby mild steel workpiece and pure copper tool electrode were used. Powder concentration of CeO2/water was varied from 0.0 to 2.0 g/L, while the current, set distance, depth of cut and delay time were kept constant at 0.8 A, 2.0 mm, 0.5 mm and 0.5 s, respectively. Results show that at 0.6 g/L concentration, MRR and machining efficiency is enhanced by 20.04% and 69.68%, while TWR is reduced by 29.25%. Minimum surface roughness is obtained at the concentration of 1.0 g/L with Ra value of 0.22 µm, whereas with distilled water dielectrical fluid this value is 1.06 µm. Scanning electron microscopy images confirm that the best surface quality with the least pores and minute microcracks is obtained at 0.6 g/L concentration. Use of CeO2/water dielectrical nanofluid also improved material hardness significantly. While the microhardness number with distilled water is 1.06 HV, it upraised as high as 1.94 HV at powder concentration of 0.6 g/L. [ABSTRACT FROM AUTHOR]

Stochastic resonance (SR) has been proved to be an effective method to extract weak-fault signals from gearboxes under strong noise. In this paper, we propose a method based on underdamped second-order SR with a new potential function. In our testing, we added an appropriate amount of Gaussian white noise to the original signal. When it matched the periodic signal and the potential function, the method showed good noise reduction ability, highlighted the fault signal and extracted fault information more effectively than the traditional SR method. The ant colony algorithm was used to optimize the potential parameters of the SR potential model and obtain the best output signal-to-noise ratio (SNR). We verified the proposed method by computer simulation and experimental verification, demonstrating that it produced better output than that of the traditional SR method. [ABSTRACT FROM AUTHOR]