Ti Content Research Articles

Geographic variation in secondary metabolites contents and their relationship with soil mineral elements in Pleuropterus multiflorum Thunb. from different regions

Abstract Background Pleuropterus multiflorum Thunb cv. “Heshouwu” (HSW) has been used as a classical material for both medicine and food in China for millennia. Recently, the cultivation region of HSW has shifted from Guangdong to Sichuan, Guizhou, and other regions. The investigation of geographic variation in bioactive metabolite contents and their relationship with soil mineral elements holds academic significance. Objective This study aimed to investigate the variations in the distribution of active components in HSW across diverse planting regions and their relationship with soil mineral elements. Methods A reliable quantitative analysis based on ultrahigh-performance liquid chromatography with triple-quadrupole mass spectrometry (UPLC-QQQ-MS) was developed to assess the levels of 15 bioactive metabolites in 60 HSW samples collected from 4 distinct regions. A total of 43 soil mineral elements in corresponding 60 soil samples were quantified by inductively coupled plasma mass spectrometry (ICP-MS). Orthogonal partial least squares-discriminant analysis (OPLS-DA), heatmap analysis, Pearson correlation analysis, and random forest (RF) regression were conducted based on the above quantitative data. Results The content of stilbene glycosides displayed a wider range of variation compared with emodin and physcion among different regions. Eight compounds were screened as the differential metabolites in HSW samples from various sources using the supervised OPLS-DA analysis. Among these, 2 important functional compounds including physcion and 2,3,5,4′-tetrahydroxystilbene-2-O-(6″-O-acetyl)-glucoside (THSG-5) are the most abundant in HSW samples from Deqing, a geographical indicative production region. Pearson correlation analysis indicated that the impact of soil mineral elements on the levels of stilbene glycosides is greater compared to that on anthraquinones. A negative correlation was observed between the levels of elements Na, Zn, Ba, Ti, and 2,3,5,4′-tetrahydroxysilbene 2-O-glucoside (THSG-1). Conversely, a positive correlation was found between the contents of elements Na, Ce, Ti, and physcion and THSG-5, 2 components that exhibited higher levels in Deqing. Furthermore, an RF algorithm was employed to establish an interrelationship model, effectively forecasting the abundance of the majority of differential metabolites in HSW samples based on the content data of soil mineral elements. Conclusions The variation of stilbene glycosides is wider than emodin and physcion in HSW. The levels of metabolites in HSW samples are influenced by soil mineral elements, with stilbene glycosides being more susceptible to such influences compared to anthraquinones. Specifically, THSG-1 shows a negative association with most soil mineral elements, notably Na, Zn, Ba, and Ti, whereas the content of physcion displays a positive correlation.

Tracking quartz and zircon provenance in sedimentary rocks using Ti distributions: Unlocking the volcanic-plutonic connection in old igneous systems

Although the relationship between silicic volcanic and plutonic rocks has been extensively studied, it remains controversial whether most plutons have volcanic counterparts and how the volcanic-to-plutonic ratio has evolved through time. This stems primarily from the scarcity of geologic examples with both volcanic and plutonic counterparts, especially in ancient terranes where volcanic deposits have likely been eroded. Here, we introduce a novel approach to identify remnant volcanic crystals in proximal siliciclastic/detrital rock formations. As most erupted crystals stop their growth before reaching the solidus, in contrast to plutonic crystals, the distribution of Ti (a proxy for temperature of crystallisation and/or magma evolution) in (weathering-resistant) quartz and zircon can help in identifying volcanic crystals in sedimentary rocks derived from supracrustal sources that have been completely eroded. Laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of quartz and zircon from volcanic and plutonic units that are known to be spatially and temporally related (from Southern Rocky Mountain Volcanic Field, Colorado, and Taupo Volcanic Zone, New Zealand) reveal that volcanic crystals have generally distinct distributions of, and on average higher Ti contents than, plutonic crystals. To further develop and test this methodology, we analysed samples from the 1.075 Ga Pikes Peak granite (CO, USA) and from the associated series of intra-granite sedimentary dikes that form part of the Cryogenian Period Tava sandstone. Blue band cathodoluminescence (CL) images can be used as a proxy for Ti-in-quartz. Our CL-screening method provides a statistically representative distribution of Ti contents in quartz crystals from individual thin sections. The Tava sandstone contains a higher concentration of high-Ti (and hence high-temperature) quartz and zircon grains than the average Pikes Peak batholith, interpreted as grains eroded from a no longer exposed, volcanic counterpart of the Pikes Peak magmatic system. Our study illustrates a means to test whether magmatic reservoirs that are now represented by crystallised ancient plutons once fed volcanic eruptions, and identifies a strategy for reconstructing volcanic-plutonic relationships, even when parts of the geological association have been eroded.

Adaptive neuro-fuzzy inference system approach for tensile properties prediction of LPDC A357 aluminum alloy

This study is based on the desire of aluminum casting foundries to understand the influence of minor changes, within the specification limits, in the alloy chemistry. In order to ensure the casting of A357 Al alloys within the framework of the casting standards and to minimize the quality problems that may arise during casting; the estimation of ultimate tensile strength (UTS), yield strength (YS) and elongation (ε) due to very small changes among the alloying elements, although they are in the standard range, by using machine learning method (ML), were studied. The dataset of chemical composition and tensile properties of Low-Pressure Die Cast (LPDC) A357 Al alloy were experimentally established. The relationship between five input variables in the A357 alloy, namely the main alloying elements Si and Mg together with the most common impurity contents Fe, Ti and Cu were selected and three outputs (i.e UTS, YS and ε) were linked by Adaptive Neuro Fuzzy Inference System (ANFIS). The ANFIS model predicted that the most detrimental element affecting tensile properties was Fe content. According to this model, the order of the relative importance on UTS, YS and ε revealed as Si, Mg and Ti content respectively after the Fe content of the alloy.

Interfacial microstructure and mechanical properties of CBN brazed in a continuous tunnel furnace with low-temperature Sn-Cu-Ti filler alloy

Currently, the most common process for manufacturing brazed cubic boron nitride (CBN) tools is vacuum brazing using Cu-based active filler alloys. However, the high brazing temperature of Cu-based alloys and the long heating time in a vacuum furnace inevitably cause severe thermal damage, thereby compromising the mechanical properties of the brazed CBN abrasives. In this study, CBN abrasives were brazed using low-temperature Sn-Cu-Ti filler alloys in a continuous tunnel furnace. The final contact angles of the Sn-Cu-Ti filler alloys on the surfaces of the brazed CBN abrasives were determined at 650 °C. When the Ti content in the alloy was 4 %, the final contact angle was 37.2° and the CBN maintained a good exposure height and achieved a firm holding force. The interfacial microstructure was analysed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). It was found that a layer of needle-like compounds, primarily comprising TiB2 and TiN, with an approximate thickness of 5 μm, was formed at the interface, indicating the formation of a chemical–metallurgical bond between the Sn-Cu-Ti alloy and CBN abrasive. The residual stresses and mechanical properties of brazed CBN abrasives with Sn-Cu-Ti and traditional Cu-based alloys were measured and compared. The results showed that compared to the brazed CBN with the Cu-based alloy, the average residual stress of the brazed CBN with the Sn-Cu-Ti alloy was reduced by 25.2 %, while the compressive strength and impact toughness increased by 25.3 % and 13.8 %, respectively. The experimental results provide new insights into reducing thermal damage to CBN for improving the processing performance of brazed CBN tools.

Thermoelectric properties enhancement and optimization of SnTe-based material with single doping: RSM-ANN approach

Tin Telluride (SnTe) stands out among semiconductor materials, drawing attention as an environmentally friendly alternative to conventional Lead Telluride (PbTe). This study explores the novel incorporation of titanium (Ti) and zirconium (Zr) as dopant elements in SnTe-based materials, an approach that has never been previously investigated. Leveraging mathematical modeling and machine learning methodologies, we use Response Surface Methodology (RSM) and Artificial Neural Network-Genetic Algorithm (ANN-GA) to predict thermoelectric properties of SnTe-based materials and find the optimum dopant element addition and operating temperature. Eleven samples featuring varying Ti and Zr concentrations are employed in experimental investigations, with dopant amounts ranging from 0 to 0.05 M. Characterization of each sample is conducted across a temperature spectrum from 50 to 450 °C, yielding a comprehensive dataset of 99 entries for neural network model construction. The generated RSM and ANN models demonstrate remarkable predictive accuracy for the thermoelectric properties of SnTe-based materials, showcasing coefficient of determination (R2) values spanning from 0.986 to 0.998. This study uses RSM and ANN-GA to predict an optimized zT value of 0.558. This value surpasses the highest zT value from the experiment by 3.33 %. In conclusion, this investigation underscores the potency of RSM and ANN as valuable tools for advancing research on SnTe-based thermoelectric materials, exemplifying their capacity to hasten the exhausting process of finding the optimum dopant addition and operating temperature.

Hot corrosion behavior of selective laser melted TiC/GT D222 nickel-based composite in 75% Na2SO4 and 25% K2SO4 molten salt medium at 900°C

PurposeThis paper aims to investigate the differences in hot corrosion behavior of the GTD222 superalloy and TiC/GTD222 composite in a mixed salt of 75% Na2SO4 and 25% K2SO4 at 900°C.Design/methodology/approachThe GTD222 superalloy and TiC/GTD222 nickel-based composite were prepared using selective laser melting (SLM). Subsequently, the hot corrosion behavior of the two alloys was systematically investigated in a salt mixture consisting of 75% Na2SO4 and 25% K2SO4 (Wt.%) at 900°C.FindingsThe TiC/GTD222 composite exhibited better hot corrosion resistance compared to the GTD222 superalloy. First, the addition of alloying elements led to the formation of a protective oxide film on the TiC/GTD222 composites 20 h before hot corrosion. Second, TiC/GTD222 composite corrosion surface has a higher Ti content, after 100 h of hot corrosion, the composite corrosion surface Ti content of 10.8% is more than two times the GTD222 alloy 4% Ti. The Ti and Cr oxides are tightly bonded, effectively resisting the erosion of corrosive elements.Originality/valueThe hot corrosion behavior of GTD222 superalloy and TiC/GTD222 composites prepared by SLM in a mixed salt of 75% Na2SO4 and 25% K2SO4 was studied for the first time. This study provides insights into the design of high-temperature alloys resistant to hot corrosion.

Effect of arc deposition process on mechanical properties and microstructure of TiAlSiN gradient coatings

In order to successfully prepare a new advanced TiAlSiN gradient coating with Ti content gradually decreased but Al content gradually increased from the cemented carbide substrate to the outermost coating surface by arc ion plating, we deeply investigated the influence mechanisms of two important process parameters. These parameters include substrate bias voltage and arc current, which affect the mechanical properties and microstructure of the gradient coating. The results show that bias voltage and arc current directly affect the particle accumulation effect on the coating surface and the re-sputtering effect caused by high-energy ion bombardment, thus affecting the deposition efficiency of the coating and the formation of defects such as macro-particles and pits on the coating surface. The increase of bias voltage is conducive to the increase of the density of columnar crystals and nanocrystals. While the increase of arc current makes the coating with high Al content transform from columnar crystals to nanocrystals. The hardness and interfacial adhesion of the gradient coatings showed a tendency of firstly increasing and then decreasing with the increase of both bias voltage and arc current. When the bias voltage and arc current are -80 V and 160 A respectively, the coating has the best mechanical properties, its surface hardness reaches 36.94 GPa, and the interfacial adhesion exceeds 120 N. In addition, with the increase of bias voltage and arc current, particles are deposited on the surface of the coating with higher energy, which leads to the preferential orientation transition from (111) to (200) plane. The high hardness of TiAlSiN coating is mainly due to the formation of high Al content of fcc-TiAlN crystals and amorphous Si3N4 in the gradient-coated surface layer. The results have important theoretical and practical significance for developing new high-performance gradient coating tools.

Effect of Soil Tillage Systems and Crop Seasonality on the Sediment Geochemical Properties Transferred into a Headwater: A Case of Study in Tobacco Plantation

ABSTRACT The global impacts of agricultural land conversion on soil erosion and pollution, particularly in tobacco cultivation areas, are well-recognized as significant contributors to soil degradation. These areas are identified as hotspots for environmental concerns due to practices that lead to increased erosion and pollution. From this perspective, this case of study explores fine sediment samples from two areas with tobacco cultivation under different tillage systems and seasonal variations, transport into a headwater, and evaluates, on a local scale: (1) the impact of tillage systems on the geochemical signature of sediments; (2) if whether crop seasonality affects these sediment geochemical signatures. The Conventional Ridge Tillage (CRT) system involves extensive soil exposure and machinery for soil management, while the Mulch Ridge Tillage (MRT) system prioritizes soil conservation and relies on herbicides for weed control. The analytical methodology used to assess the sample element characteristics was Energy Dispersive X-ray Fluorescence (EDXRF). It was applied on the twenty fine sediments (ten of harvest and ten of inter-harvest season of tobacco) to quantitatively assess their inorganic composition. Additionally, Pearson correlation analysis, Hierarchical Cluster Analysis (HCA), and Principal Component Analysis (PCA) were applied on the EDXRF data to highlight the similarities and, thus, providing information to assess the complex data clustering patterns. As a result, the sediment compositions from the two studied soil systems are not similar. The PCA showed that the CRT sediments are characterized by the P, S, K, Ca, and Mn content, presenting a geochemical signature related to manure and fertilizer compared to the MRT, which is correlated with Al, Ti, Fe, Cu, and Zn contents, exhibiting a geochemical signature characterized by the natural soil composition. Therefore, the sediment geochemical signatures might be affected by two phases in the study area: a) tillage system characteristics and b) seasonal soil erosion. These findings underscore the importance of managing soil nutrients to mitigate soil pollution and nutrient exportation to aquatic systems. Moreover, the results emphasize the recommendations for sustainable agricultural practices in tobacco-growing areas to protect environmental quality.

Sunflower-like eutectic solidification in gas atomized Al0.3CrFeNiTi0.3 medium-entropy alloy powders: A comprehensive microstructural study

The addition of larger atomic size elements, such as Al and Ti, to CrFeNi medium-entropy alloys (MEAs) offers a strategic approach to overcome the strength-ductility trade-off. This study focuses on examining the morphological, solidification, phase, and elemental characteristics of Al0.3CrFeNiTi0.3 feedstock powders produced through gas atomization (GA). The rapid cooling rate inherent in GA results in sunflower-like eutectic solidification. This structure exhibits firstly solidified Cr-rich BCC phases filled with cuboidal-shaped L21-type precipitates, each measuring up to ∼20 nm. Their peripheral regions display outward and radial growth of L21 and Fe-rich BCC eutectic phases, while FCC phase develops at the remaining sites. Intermediate B2 layers between BCC and L21 phases are considered as kinetic buffers, which enhance the interfacial stability. The size and shapes of powders determine their cooling rates, leading to a transition from comparably large sunflower-like eutectic structures to finer equiaxed grains alongside reduced elemental segregation with decreasing powder size. Nano-hardness measurements demonstrate superior mechanical strength in the peripheral regions due to the higher volume fraction of the L21 phase and its optimal interfacial coherency with the Fe-rich BCC phase. Furthermore, the slightly higher concentrations of Al and Ti in Fe-rich BCC phase (compared to the Cr-rich BCC phase) induce a better lattice distortion effect.

Dual-mineralization in the intracontinental Jiangnan Orogen, South China: Evidence from textures and in-situ trace elements and oxygen analysis of quartz from the Woxi Au-Sb-W deposit

The Jiangnan Orogenic Belt (JOB), situated in the interior of the South China Block (SCB), harbors numerous gold-polymetallic deposits, but the ore genesis has been a long-standing controversy. This study examines the Woxi super-large gold deposit in the middle JOB, which is characterized by simultaneous large-scale antimony-tungsten mineralization. The investigation shows that the Woxi ore deposit have developed multiple-stage quartz, i.e., Qz1 (early quartz-carbonate, stage I), Qz2 (quartz-wolframite-scheelite, stage II), Qz3a (quartz-gold-pyrite, early stage III), Qz3b (quartz-stibnite-scheelite, late stage III) and Qz4 (late quartz-carbonate, stage IV). We conducted SEM-CL texture imaging, LA-ICP-MS trace element, and SIMS oxygen isotope analysis on the quartz samples from the main mineralization stages (mainly Qz2 and Qz3). The results reveal a dual mineralization process of the Woxi gold-antimony-tungsten deposit. In the initial stage, the quartz (Qz2) exhibits intense brightness in CL imaging and spiderweb-like texture, shows high concentrations of trace elements, especially Ge, Al and Ti, and has δ18Ofluid values ranging from 10.84 ‰ to 11.64 ‰. These characters are consistent with a magmatic fluid that is acidic (pH<3), reducing, and of relatively high-temperature. In the second stage, the quartz (including Qz3a, Qz3b and Qz4) shows relatively darker CL image and band texture or cobweb mosaic coexistence texture, low concentrations of trace elements, especially Al and Ti, and a low δ18Ofluid values (8.01 ‰ to 9.19 ‰ for Qz3a and 5.83 ‰ to 6.51 ‰ for Qz3b) consistent with characteristics of mantle-derived fluids. The results of this study supports an “intracontinental reactivation metallogenic model”, in which the gold-polymetallic deposits in the JOB formed from a dual-stage mineralization related to tectono-magmatic activities in a back-arc setting. The dual ore-forming processes revealed in this study provide important insights for a comprehensive understanding of the gold-polymetallic deposits in the JOB, and it may be a significant mechanism in the formation of large to super-large gold-polymetallic deposits in this region, which is indicative perspective for exploration of the gold-polymetal deposits. Our work also demonstrates that quartz is an effective tool for identifying the mineralization in the JOB.

Effect of ladle slag composition on the cleanliness of Al-Ti deoxidized interstitial-free steel

The effect of slag composition on the cleanliness of Al-Ti deoxidized interstitial-free steel produced via basic oxygen furnace (BOF)-ladle furnace (LF)-Ruhrstahl-Heraeus (RH)-continuous casting (CC) process was investigated by the systematic samplings and analyses for four heats in a steel plant in China. Oxygen/nitrogen analyzer, automatic scanning electron microscope, field-emission scanning electron microscope, and energy spectroscopy analysis were used to analyze the variations of number, size, type, and morphology of inclusions in molten steel from RH to tundish, and X-ray fluorescence was used to analyze the slag composition. The relationship between slag composition and inclusion characteristics in molten steel was investigated. The effect of slag composition on the oxygen mass transfer from the slag–metal interface to liquid steel was also studied through a theoretical calculation. The results showed that the cleanliness of molten steel was greatly affected by the slag composition. The deterioration of steel cleanliness was mainly arisen from a serious reoxidation of molten steel by oxidizing components like (T.Fe + MnO) in top slag during RH refining process. A weak ability to absorb inclusions of top slag with high CaO/Al2O3 and CaO/SiO2 mass ratios was confirmed from the inclusions analyses. The size and number of Al2O3 inclusion clusters were larger, and Ti content in Al2O3-TiO x inclusions was higher from RH to tundish in the case of serious reoxidation. The reduction of FeO content and keeping the CaO/Al2O3 and CaO/SiO2 ratios at about 1.6 and 4–7, respectively, in top slag during RH refining process was beneficial to minimize the reoxidation of Al and Ti and increase the inclusion absorption ability of top slag.

Preparation of High-Purity Quartz Sand by Vein Quartz Purification and Characteristics: A Case Study of Pakistan Vein Quartz

This study focuses on the purification and evaluation of the high-purity quartz (HPQ) potential of vein quartz ore from Pakistan. Vein quartz is grayish-white and translucent, with its mineral composition mainly comprising quartz crystal. Processed quartz sand is obtained from quartz raw ore through purifying technologies, including crushing, ultrasonic desliming, flotation, high-temperature calcination, water quenching, hot pressure acid leaching, and chlorination roasting. The microscopic characteristics show that the vein quartz raw ore has a medium-coarse granular metacrystalline structure, high quartz content, with only a small quantity of fine-grained K-feldspar. The inclusions primarily consist of large-sized primary inclusions and secondary fluid inclusions developed along the micro-fractures, and the content of inclusions in most areas of the crystal is very low or even nonexistent. The quartz ore with such inclusion characteristics is considered a relatively good raw material for quartz. Component analysis shows that the main impurity elements in the quartz ore are Al, K, Ca, Na, Ti, Fe, and Li, with a total impurity element content of 128.86 µg·g−1. After purification, only lattice impurity elements Al, Ti, and Li remain in the processed quartz sand, resulting in a total impurity element content of 24.23 µg·g−1, an impurity removal rate of 81.20%, and the purity of SiO2 reaching 99.998 wt.%. It is suggested that when the quartz raw ore contains high content of lattice impurity elements, such as Al, Li, and Ti, it is difficult to remove them by the current purification method. In industrial production, considering the economic cost, if quartz sand still contains high content of lattice impurity elements Al, Ti, and Li after flotation, it cannot be used as a raw material for high-end HPQ.

Effect of Ti content on microstructure evolution and mechanical properties of FeCoNi-based medium-entropy alloys

Effect of Ti content on microstructure evolution and mechanical properties of FeCoNi-based medium-entropy alloys

Effect of Addition of Ti on Selected Properties of AlSi5Cu2Mg Alloy

The paper focuses on the investigation of the influence of Ti on selected properties of the hypoeutectic aluminium alloy AlSi5Cu2Mg. AlSi5Cu2Mg alloy finds application in the field of production of high-strength cylinder head castings intended for the automotive industry due to the optimal combination of mechanical, physical and foundry properties. In commercial production, the maximum Ti content is limited by the manufacturer (Ti max. = 0.03 wt.%), which significantly limits the possibilities of refinement the alloy with Ti-based grain refiners. Therefore, the possibility of increasing the Ti content beyond the manufacturer's recommendation is considered in this work. The main aim of the work is to evaluate the influence of graded Ti addition (0.1; 0.2; 0.3 wt.% Ti) on the resulting mechanical and physical properties of the AlSi5Cu2Mg alloy. Simultaneously, the influence of increased Ti content on the microstructure of AlSi5Cu2Mg alloy is evaluated. The alloying element was introduced into the melt in the form of AlTi5B1 master alloy. The effect of T6 heat treatment on the resulting mechanical and physical properties and microstructure of the hypoeutectic AlSi5Cu2Mg alloy with graded Ti addition was also investigated in the experimental work.

Investigating the efficiency of electrocoagulation using similar/dissimilar electrodes for the detoxification of Coralene Rubine dye: a cost effective approach.

Efficient treatment of textile dyeing wastewater can be achieved through electrocoagulation (EC) with minimal sludge production; however, the selection of the appropriate electrode is essential in lowering overall costs. Also, the reuse of the treated aqueous azo dye solution from this process has not been explored in detail. With these objectives, this study aims to treat synthetic azo dye solutions and achieve high colour removal efficiency (CRE%) using similar (Ti-Ti) and dissimilar (Ti-Cu) metal electrodes through EC with an attempt to reduce the cost. The aqueous Coralene Rubine GFL azo dye was used to examine the efficiency and cost of the EC process. X-Ray Photoelectron Spectroscopy was used to study the EC mechanism, while High Performance Liquid Chromatography was used to analyse the degradation of the dye and the formation of intermediate compounds. The concentration of metal ions in the treated dye solution was quantified using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), with Ti-Ti treated solution having 14.20mg/L concentration of Ti and Ti-Cu treated solution having 0.078mg/L of Ti and 0.001mg/L of Cu, respectively. Colour removal efficiency of 99.49% was obtained for both electrode sets, with a lower operating time and voltage for dissimilar metal combination. Ecotoxicity studies showed negligible toxicity of Ti-Cu treated dye samples compared to untreated solutions. Survival rate, protein estimation, and catalase activity was used to validate the treatment method's efficacy. The study found that the dissimilar electrode material exhibited reduced toxicity due to the presence of heavy metals below the permissible limit.

Fabrication and characterization of Ti-12Mo/xAl2O3 bio-inert composite for dental prosthetic applications.

Introduction: Titanium (Ti)-molybdenum(Mo) composites reinforced with ceramic nanoparticles have recently significant interest among researchers as a new type of bio-inert material used for dental prosthetic applications due to its biocompatibility, outstanding physical, mechanical and corrosion properties. The current work investigates the impact of alumina (Al2O3) nanoparticles on the properties of the Ti-12Mo composite, including microstructure, density, hardness, wear resistance, and electrochemical behavior. Methods: Ti-12Mo/xAl2O3 nanocomposites reinforced with different Al2O3 nanoparticles content were prepared. The composition of each sample was adjusted through the mechanical milling of the elemental constituents of the sample for 24h under an argon atmosphere. The produced nanocomposite powders were then cold-pressed at 600 MPa and sintered at different temperatures (1,350°C, 1,450°C, and 1,500°C) for 90min. Based on density measurements using the Archimedes method, the most suitable sintering temperature was found to be 1,450°C. The morphology and chemical composition of the milled and sintered composites were analyzed using back-scattering scanning electron microscopy (SEM) and X-ray diffraction (XRD). Results and Discussion: The results showed that the addition of Mo increased the Ti density from 99.11% to 99.46%, while the incorporation of 15wt% Al2O3 in the Ti-12Mo composite decreased the density to 97.28%. Furthermore, the Vickers hardness and wear behavior of the Ti-Mo composite were enhanced with the addition of up to 5 wt% Al2O3. The sample contains 5 wt% Al2O3 exhibited a Vickers hardness of 593.4HV, compared to 320HV for pure Ti, and demonstrated the lowest wear rate of 0.0367mg/min, compared to 0.307mg/min for pure Ti. Electrochemical investigations revealed that the sintered Ti-12Mo/xAl2O3 nanocomposites displayed higher corrosion resistance against a simulated artificial saliva (AS) solution than pure Ti. The concentrations of Ti, Mo, and Al ions released from the Ti-12Mo/xAl2O3 nanocomposites in the AS solution were within the safe levels. It was found from this study that; the sample of the composition Ti-12Mo/5wt%Al2O3 exhibited appropriate mechanical properties, biocompatibility, corrosion resistance against the AS solution with acceptable ion concentration released in the biological fluids. Therefore, it can be considered as a new bio-inert material for potential applications in dental prosthetics.

Effects of Cooling Rate and Ti Content on the Solidification Characteristics of Al-Ti Alloys

Effects of Cooling Rate and Ti Content on the Solidification Characteristics of Al-Ti Alloys

Changes in the structure of red mud and black nickel mud after activation

This paper deals with the evaluation of the structure of selected hazardous wastes from the production of metals, namely waste from the production of aluminium - red mud and waste from the production of nickel - black nickel mud. In environmental applications, red mud and black nickel mud are likely to be used after activation. The samples were activated using hydrochloric acid to study the structure properties before and after the treatment. Both of these wastes have suitable adsorption and catalytic properties that could be positively affected by the activation of their surfaces. The morphology of the samples was documented by scanning electron microscope, phase analysis was performed using diffraction techniques, and the content of elements was determined by EDX analysis. Also, FTIR analysis of the samples was performed. Activation increases the specific surface area of samples, which is beneficial in many environmental applications, such as in the adsorptive removal of pollutants. Treatment of samples changes the surface properties of the adsorbent, such as electrostatic, hydrophobic, and hydrophilic. The activation creates a new surface structure and thus affects its properties. EDX analysis confirmed the high content of Fe, Al, Si and Ti, which are responsible for good adsorption and catalytic properties. X-ray diffractograms have shown only slight changes in the structure of wastes after activation. The results of SEM confirmed the changes in the surface structure and the creation of new active centres necessary for the successful adsorption process. The FTIR analysis determined the changes in the structure of the samples mainly due to the thermal degradation of C=O and O-Si-O bonds.

Distribution and accumulation of UV filters (UVFs) and conservation status of Posidonia oceanica seagrass meadows in a prominent Mediterranean coastal tourist hub

This study investigates the presence and impact of UV filters in Posidonia oceanica meadows in Formentera, a Mediterranean tourist hotspot. It highlights the distribution of inorganic (TiO2 and ZnO) and organic UV filters (UVFs) in different environmental matrices, their accumulation in seagrass tissues and their impact on the seagrass health.In the overlying and canopy waters of P. oceanica, Zn concentrations surpassed Ti, with three organic UVFs (benzophenone-3 [BP-3], avobenzone and homosalate [HMS]) consistently detected. Ti concentrations were generally higher than Zn in rhizosphere sediments, along with recurrent presence of octocrylene, HMS, 2-ethylhexyl methoxycinnamate (EHMC), and 4-methylbenzylidene camphor (4-MBC). Maximum Zn concentrations were found in canopy waters (3052.9 ng L−1). Both Ti and Zn were found in all P. oceanica tissues and leaf epiphytes across all study sites. Additional UVFs like octocrylene, avobenzone, and BP-8 were also detected in P. oceanica tissues and epiphytes. Elevated levels of octocrylene in leaf epiphytes (2112.1 ng g−1 dw) and avobenzone in leaves (364.2 ng g−1 dw) and leaf epiphytes (199.6 ng g−1 dw) were observed in the Port of La Savina, the island's main entry port. Octocrylene concentrations (up to 2575 ng g−1 dw) in rhizosphere sediments near sewage discharge points exceeded reported maxima, highlighting wastewater treatment plants as significant sources of organic UVFs. Correlational analyses suggested that the accumulation of octocrylene, avobenzone, and BP-3 negatively impacted P. oceanica's conservation status, affecting global density, density at 100 % cover, and leaf morphometry. Positive correlations were observed between leaf polyphenols (antioxidants) and concentrations of avobenzone, benzophenone-8 (BP-8), and BP-3, indicating potential oxidative stress induced by UVFs in P. oceanica.Our study underscores the pervasive presence of UV filters in P. oceanica habitats, with implications for seagrass health and conservation, especially in areas of high tourism and sewage discharge.

Effect of chemical abrasion of zircon on SIMS U–Pb, δ18O, trace element, and LA-ICPMS trace element and Lu–Hf isotopic analyses

Abstract. This study assesses the effect of chemical abrasion on in situ mass spectrometric isotopic and elemental analyses in zircon. Chemical abrasion improves the U–Pb systematics of SIMS (secondary ion mass spectrometry) analyses of reference zircons, while leaving other isotopic systems largely unchanged. SIMS 206Pb/238U ages of chemically abraded reference materials TEMORA-2, 91500, QGNG, and OG1 are precise to within 0.25 % to 0.4 % and are within uncertainty of chemically abraded TIMS (thermal ionization mass spectrometry) reference ages, while SIMS 206Pb/238U ages of untreated zircons are within uncertainty of TIMS reference ages where chemical abrasion was not used. Chemically abraded and untreated zircons appear to cross-calibrate within uncertainty using all but one possible permutation of reference materials, provided that the corresponding chemically abraded or untreated reference age is used for the appropriate material. In the case of reference zircons QGNG and OG1, which are slightly discordant, the SIMS U–Pb ages of chemically abraded and untreated material differ beyond their respective 95 % confidence intervals. SIMS U–Pb analysis of chemically abraded zircon with multiple growth stages is more difficult to interpret. Treated igneous rims on zircon crystals from the S-type Mount Painter Volcanics are much lower in common Pb than the rims on untreated zircon grains. However, the analyses of chemically abraded material show excess scatter. Chemical abrasion also changes the relative abundance of the ages of zircon cores inherited from the sedimentary protolith, presumably due to some populations being more likely to survive the chemical abrasion process than others. We consider these results from inherited S-type zircon cores to be indicative of results for detrital zircon grains from unmelted sediments. Trace element, δ18O, and εHf analyses were also performed on these zircons. None of these systems showed substantial changes as a result of chemical abrasion. The most discordant reference material, OG1, showed a loss of OH as a result of chemical abrasion, presumably due to dissolution of hydrous metamict domains or thermal dehydration during the annealing step of chemical abrasion. In no case did zircon gain fluorine due to exchange of lattice-bound substituted OH or other anions with fluorine during the HF partial dissolution phase of the chemical abrasion process. As the OG1, QGNG, and TEMORA-2 zircon samples are known to be compositionally inhomogeneous in trace element composition, spot-to-spot differences dominated the trace element results. Even the 91500 megacrystic zircon pieces exhibited substantial chip-to-chip variation. The light rare earth elements (LREEs) in chemically abraded OG1 and TEMORA-2 were lower than in the untreated samples. Ti concentration and phosphorus saturation ((Y + REE) / P) were generally unchanged in all samples.