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Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys. However, it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity. Herein, a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium, which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating. The multiscale microstructures with nanoscale stacks and microscale spheres on the surface, as well as the through-thickness stearates, lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating.

In an effort for further improvement of LSCF hollow fiber membrane properties in oxygen purification application, this work studied the use of polyethylene glycol (PEG) with different molecular weight of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

A new NLO crystal of L-Arginine doped with potassium iodide were harvested from solution growth technique with slow evaporation method. Powder X-ray diffraction analysis exposes the structure. Presence of vibration functional groups in the grown crystal was confirmed by FTIR spectroscopy. Using the spectrum of UV–Vis-NIR the optical transmission and absorption spectra were studied. TGA-DSC studies reveal the decomposition and thermal stabilities of the grown crystals. Kurtz Perry Powder technique determines the second harmonic generation NLO behavior.

The rapid degradation of magnesium (Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca (denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag (denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag (denoted as ZQ63), were fabricated by alloying with calcium (Ca), zinc (Zn) and silver (Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.

Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys. However, poor wear resistance and microcracks formed during the solidification have limited it extensive application. There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys. Herein, the epoxy resin powder coating with polydopamine modified molybdenum disulfide (MoS2@PDA-EP powder coating with 0, 0.1, 0.2, 0.5, 1.0 wt.% loading) was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance. The results revealed that the addition of MoS2@PDA enhanced the adhesion strength between coatings and alloys, wear resistance and corrosion protection of the powder coatings. Among them, the optimum was obtained by 0.2 wt.% MoS2@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix. To conclude, MoS2@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.

Sulfation of wheat straw soda lignin by the sulfamic acid–urea mixture in different solvents has been investigated for the first time. The effect of a catalyst used in the lignin sulfation process on the yield of the lignin sulfates and sulfur content in them has been explored. It has been found that the optimal medium for the lignin sulfation with sulfamic acid is dioxane and, in the presence of a catalyst, urea. Although the sulfated lignins obtained using the reaction in dimethyl sulfoxide and diglyme have the maximum sulfur contents (11.2% and 9.9%, respectively), these products are difficult to isolate and purify, which complicates the use of these solvents. Sulfated lignin obtained in the dioxane medium has a high (10.1%) sulfur content and is easy to isolate and purify. The incorporation of sulfate groups into the lignin structure has been confirmed by the infrared and nuclear magnetic resonance spectroscopy investigations. In the infrared spectra of sulfated lignin, characteristic absorption bands at 800–860 and 1260–1200 cm−1 appear. The dominant substitution of aliphatic hydroxyl groups has been confirmed by the nuclear magnetic resonance spectroscopy study. It has been found that, during the modification and purification of lignin, the latter is fractionated, which results in the redistribution of molecular weights toward the high molecular-weight region, as well as the removal of some low-molecular-weight components, which is reflected in a decrease in the number of signals in the nuclear magnetic resonance spectra.

Rare earth elements (lanthanide and yttrium, abbreviated as REY) provide important support for national security, energy production, environmental protection and economic growth. In recent years, many studies have shown that the content of REY in some coal or coal by-products is close to or even higher than that in traditional REY ore, which makes coal a potential source of REY. This study took the No. 17 coal of Panzhou mining area in Liupanshui coal field as the research object, and the content and occurrence modes of REY in raw coal and 7 density fraction samples were studied. The results show that the content of REY in the raw coal reaches 220.67 μg/g, which is significantly higher than the average REY in the World coal and Chinese coal as reported in the literature. Gravity separation has a certain pre-enrichment effect on REY and the fraction sample ＞1.8 g/cm3 has the highest REY of 426.27 μg/g (equal to rare earth oxide 0.1%). Study on correlation between REY and ash yields reveals that the organic affinity of the light rare earth is higher than the medium rare earth and the heavy rare earth. As shown by XRD and XRF, the major minerals in coal are kaolinite, quartz and calcite, and the content of REY in coal is significantly related to Al and Si and kaolinite, which implies that REY occur mainly in kaolinite. LA-ICP-MS was adopted to determine chemical composition of micro-zone in kaolinite in coal and the results show that there is no obvious correlation between REY and the content of Al and Si. This indicates that the REY occurred probably in the form of adsorption. The research results provide a scientific reference for the potential extraction of the associated REY in the coal.

Hydroxyl terminated poly(dimethylsiloxane) (PDMS-HT) is used as an electrolyte additive in electrolyte systems containing 1 M LiPF6 in EC:DMC (ratios 1:9; 3:7; 4:6 and 1:1 v/v) to enhance the cycle performance of lithium-ion batteries. Adding a small amount of PDMS-HT to the standard LIB electrolyte leads to improved specific capacity as well as improved capacity retention over prolonged cycles. There is also a slight increase in Li+ ion conductivity when PDMS-HT is added. Also, the PDMS-HT additive allows the formation of a more stable solid electrolyte interface (SEI) layer that enables the LIB cells to be cycled for longer cycles with minimal capacity fading. This combination of improved ionic conductivity and stable SEI layer formation due to the PDMS-HT additive, makes it an excellent candidate for an electrolyte additive for lithium ion batteries.

In this study, Ti6Al7Nb titanium alloy has been subjected to micro-arc oxidation (MAO) process and hydrothermal (HT) treatment sequentially. MAO process was conducted in calcium acetate hydrate (Ca(CH3COO)2.H2O) and disodium hydrogen phosphate anhydrous (Na2HPO4) containing reference electrolyte with and without the addition of silver acetate (AgC2H3O2) to provide antibacterial efficiency along with good bioactivity. Subsequently, HT treatment was employed to MAO’ed samples in an alkaline solution (pH = 11) at 230°C. HT treatment induced the covering of the titanium oxide (TiO2)-based MAO coatings with 1–2 µm thick exterior layer composed of nano-rods of titanium oxide and hexagonal columns of hydroxyapatite (HA). The presence of silver (Ag) in the MAO coating refined the structure of the HT treatment-induced exterior layer. As the primary indication of enhancement of the bioactivity, HT treatment accelerated apatite formation in the SBF solution irrespective of the silver presence, which delayed the apatite formation on the untreated MAO coatings. Moreover, HT treatment reduced the release of silver from the coatings into the SBF solution.

A nitrogen-sulfur dual-doped citric-acid porous carbon/sulfur (NS-CAPC/S) materials was prepared by an easy hydrothermal method applying glutathione as nitrogen-sulfur origin and citric-acid carbon as carbon origin. The detailed structure of the materials was determined through raman spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction tests. The appearance of the materials was investigated via transmission electron microscopy and scanning electron microscopy methods. N2 adsorption–desorption isotherm was applied to test its pore size distribution and pore structure. Thermogravimetric analysis (TGA) was utilized to identify the mass ratio of sulfur. The NS-CAPC/S materials was employed as positive electrode material in Li-S batteries. Electrochemical performance revealed the prepared NS-CAPC/S composite possessed good specific capacity, exceptionally high cycle stability and excellent rate performance.

The present work reports the results of the lignin molecule degradation studies using nitrogen-doped ZnO photocatalysts supported on graphene oxide. Three different nitrogen precursors were used to achieve the nitrogen doping in ZnO, namely urea, ethylenediamine, and thiourea, using a microwave-assisted hydrothermal method. Our purpose is to demonstrate that different nitrogen precursors give rise to different amounts of doping in ZnO, which in turn, favorably affects their photocatalytic behavior. The synthesized compounds were tested on the lignin degradation reaction, under visible (Vis) and ultraviolet (UV) energy irradiation. Structural and physicochemical properties of prepared samples were investigated to provide explanation of the photocatalytic behavior observed in samples. XPS analyses were developed to determine differences in nitrogen content, as well to determine the proportion of N-N or O-Z-N binding in samples. Remarkable structural and photocatalytic differences were found for every sample as effect of the nitrogen precursor. Photocatalytic activity tests revealed that the percentage of lignin degradation under UV irradiation was 80 %; while using Vis energy the degradation value was 61 %.

Urea–formaldehyde (UF) resin is the most important used adhesive in the production of wood-based composite panels, such as particleboard, medium-density fiberboard, oriented strand board and plywood. The aim of this work was to investigate the influence of nanocellulose, boric acid and borax on the chemical performance properties of UF resin. UF resin was reinforced with various loading levels of nanocellulose, boric acid and borax. Formaldehyde emission, gel time, solid content, viscosity, pH, specific gravity, shelf life and Fourier transform infrared spectra were evaluated as indicators of chemical performance. The findings showed that the formaldehyde emission of hybrid UF resin reinforced with nanocellulose/boron compounds decreased by up to 31.25%. The use of the reinforcement technique in the resin caused an increase in shelf life, viscosity and gel time but caused a reduction in the solid content of the resin. The apparent specific gravity of the resin was not influenced by the addition of nanocellulose/boron compounds. It was concluded that the chemical performance properties of UF resin could be enhanced by using proper nanocellulose, boric acid and borax loading levels. By using the reinforcement technique, it was possible to produce low-formaldehyde-emitting adhesives so that environmentally friendly products could be manufactured.

Fabrication of selective adsorption coatings plays a crucial role in solid-phase microextraction (SPME). Herein, new strategies were developed for the in-situ fabrication of novel cobalt-based carbonaceous coatings on the nickel-titanium alloy (NiTi) fiber substrate using ZIF-67 as a precursor and template through the chemical reaction of ZIF-67 with glucose, dopamine (DA) and melamine, respectively. The adsorption performance of the resulting coatings was evaluated using representative aromatic compounds coupled to high-performance liquid chromatography (HPLC) with ultraviolet detection (HPLC-UV). The results clearly demonstrated that the adsorption selectivity was subject to the surface elemental composition of the fiber coatings. The cobalt and nitrogen co-doped carbonaceous coating showed better adsorption selectivity for ultraviolet filters. In contrast, the cobalt-doped carbonaceous coating exhibited higher adsorption selectivity for polycyclic aromatic hydrocarbons. The fabricated fibers present higher mechanical stability and higher adsorption capability for model analytes than the commercial polydimethylsiloxane and polyacrylate fibers. These new strategies will continue to expand the NiTi fibers as versatile fiber substrates for metal-organic frameworks (MOFs)-derived coating materials with controllable nanostructures and tunable properties.

In this work, we investigated leaching of lanthanide and yttrium (REY) from a Central Appalachian coal and its ashes obtained at 550–950 °C with the main purpose of understanding the impact of ashing temperature on REY leachability in water, ammonium sulfate, and hydrochloric acid. It is found that the coal contains a negligible amount of water-soluble REY, less than 1% ion-exchangeable REY, and about 28% of HCl-soluble REY. Ashing leads to dramatic changes in REY leachability in both ammonium sulfate and hydrochloric acid solutions, which is believed to be related to transformation and redistribution of organically-associated REY in coal during the ashing process. Ashing temperature significantly affects REY leaching from coal ashes; higher ashing temperature results in lower REY leachability in both solutions. Clay minerals may play a significant role in changing the leachability of REY after ashing. In addition, the results also suggest that the organic matter in the coal is relatively enriched in heavy REY.

Attempt of developing bio-safety and functional layered double hydroxides (LDHs) modified plasma electrolytic oxidation (PEO) coatings, has become a hotspot in the protection of magnesium (Mg) based biomedical implants. In the present work, Mg-Fe LDH films with different Fe contents were fabricated on PEO coating via a novel two-step method: firstly, the FeOOH films were prepared by immersing PEO sample in Fe2+-containing solution, and then Mg-Fe LDH films were formed by transforming the FeOOH films via a hydrothermal treatment in water. The highly-oriented LDH nano-sheets could enhance the anti-corrosion performance of PEO coating, which was proved by the results of electrochemical test, hydrogen evolution and corroded morphology. PEO/Mg-Fe LDH coatings showed a low hemolysis rate (less 5%) than PEO coating. In addition, PEO/Mg-Fe LDH coatings were more favorable for cell adhesion and proliferation than PEO coating. Moreover, PEO/Mg-Fe LDH coatings showed good photothermal conversion property, which demonstrated the excellent rapid antibacterial effect under NIR light. In vitro culture of rat bone marrow stem cell (rBMSC) suggested that cells cultured in the extract of PEO/Mg-Fe LDH coatings had a better osteogenic activity. In vivo subcutaneous implantation test revealed that PEO/Mg-Fe LDH coatings exhibited good anti-corrosion and histocompatibility.

High-voltage and low-cost manganese-based P2-type oxides show real promise as promising cathode for sodium-ion batteries (SIBs). But the P2−O2 phase transformation and Na+/vacancy ordering results in the inferior structural stability and Na+ diffusion coefficient, which further leads to rapid decay of capacity and poor rate capability. Herein, in consideration of the synergetic effects of dual cationic doping, electrochemically inactive Li+ and active Co3+ co-doping are proposed to solve the above issues. The novel two-step doping strategy, Co doping during synthesis of precursors via co-precipitation reaction followed by Li doping during solid-state reaction, are rationally developed. As anticipated, the Li, Co co-doped P2-type oxide exhibits the absence of P2−O2 phase transformation and Na+/vacancy disordering, which gives rise to an outstanding cycling stability (86.7% capacity retention within 100 cycles at 0.1C) and high-rate capability (reversible capacity of 109 mAh g−1 even at 10C). In addition, the full-cells composed of the co-doped P2-type positive and hard carbon negative show high energy-density, good lifespan and high-rate property. This proposed cationic co-doping provides an effective and scalable tactics for modulating the structural properties of high-voltage P2-type cathodes for advanced SIBs.

Metal-free heteroatom doped nanocarbons are promising alternatives to the metal-based materials in catalytic ozonation for destruction of aqueous organic contaminants. In this study, N, S co-doped hollow carbon microspheres (NSCs) were synthesized from the polymerization products during persulfate wet air oxidation of benzothiazole. The contents of doped N and S as well as the structural stability were maneuvered by adjusting the subsequent N2-annealing temperature. Compared with the prevailing single-walled carbon nanotubes, the N2-annealed NSCs demonstrated a higher catalytic ozonation activity for benzimidazole degradation. According to the quantitative structure-activity relationship (QSAR) analysis, the synergistic effect between the graphitic N and the thiophene-S which redistributed the charge distribution of the carbon basal plane contributed to the activity enhancement of the N2-annealed NSCs. Additionally, the hollow structure within the microspheres served as the microreactor to boost the mass transfer and reaction kinetics via the nanoconfinement effects. Quenching and electron paramagnetic resonance (EPR) tests revealed that benzimidazole degradation was dominated by the produced singlet oxygen (1O2) species, while hydroxyl radicals (•OH) were also generated and participated. This study puts forward a novel strategy for synthesis of heteroatom-doped nanocarbons and sheds a light on the relationship between the active sites on the doped nanocarbons and the catalytic performance.

The deterioration of drilling fluid properties during deep drilling causes problems like inefficient cutting removal, fluid invasion, and shale swelling, which increases non-productive time (NPT) and cost. Recently nanoparticles (NPs) based drilling fluid are introduced to address these impediments since these particles prove their advantages in different stages of petroleum exploration and recovery. Previous developments are concerned with the use of commercial zinc oxide (ZnO) NPs in inorganic KCl salt-based drilling fluid, although application of KCl in drilling fluid arouses environmental complications. In this study, ZnO NPs prepared in the laboratory are used in water-based drilling fluid (WBDF) to assess the effect of nanoparticles on the properties of drilling fluid at two temperature conditions of 40 °C and 80 °C. A base mud is formulated, and ZnO NPs with five different concentrations of 0.05, 0.1, 0.5, 1.0, and 2.0 wt% are mixed with the base mud. The experimental analysis shows that NPs improve the rheological properties of WBDF. When the concentration of NPs was 0.1 wt%, the yield point increased by 61.54% at 40 °C, and when the concentration of NPs was 0.05 wt%, the yield point increased by 60% at 80 °C. Besides, when the concentration of NPs is 0.05 wt%, 10-sec gel strengths are enhanced by 25% and 50% at 40 °C and 80 °C, respectively. The API low-pressure low-temperature (LPLT) filter volume is not significantly affected by the addition of NPs in WBDF. However, mud cake thickness continuously reduces with the increase of NPs concentrations. This result reveals that a superior rheological improvement is achieved at low NPs concentration (0.05 wt%) at higher temperature.

Statement of problem How axial displacement may be affected by the mechanical properties and internal discrepancy of a cement-retained implant-supported prosthesis is unclear. Purpose The purpose of this in vitro study was to assess the difference in internal discrepancy and axial displacement according to the prosthesis material in cement-retained prostheses splinting nonparallel implants. Material and methods Computer-aided design and computer-aided manufacture (CAD-CAM) titanium abutments were fabricated for a vertically placed implant and a 15-degree tilted implant. Three types of prostheses, in zirconia, cobalt-chromium (Co-Cr) alloy, and polymethylmethacrylate resin (PMMA), were fabricated (n=10). The internal discrepancy between the CAD-CAM titanium abutment and the prosthesis was measured by using the replica technique. After luting with an interim cement, they were mounted in Type IV gypsum. The specimens were cyclic loaded, and axial displacement of the prosthesis was measured after 3, 10, 100, and 106 cycles. The internal discrepancy and cumulative axial displacement were assessed by using a 3-way analysis of variance and repeated measures analysis of variance (α=.05). Results The internal discrepancy of the prosthesis did not differ based on the prosthesis material (P=.869); however, it was significantly different based on the measurement location, with the occlusal discrepancy (224 ±29 μm) being greater than the axial discrepancy (21 ±10 μm) (P Conclusions Prostheses made with high-elastic moduli materials exhibited less axial displacement than PMMA prostheses, even though the internal discrepancy was not different. Moreover, vertically placed implants presented a greater axial displacement of the prosthesis than implants with angled placement.

Arsenic (As) contamination poses an urgent environmental risk, and its removal from groundwater remains a challenge due to the lack of efficient adsorbents. Herein, a novel granular chitosan-titanium (CS-Ti) adsorbent was fabricated by the sol-gel method. Batch experiments show that As(V) adsorption on CS-Ti followed the pseudo-second-order kinetic model, and the adsorption isotherm conformed to the Freundlich model with the correlation coefficient of 0.99. In situ FTIR spectra revealed that the CS-Ti adsorbent was composed of amorphous TiOx and chitosan by forming C-O-Ti and N-Ti bonds, and the amorphous TiOx was responsible for As(V) adsorption. Rapid small-scale column tests show that 165.6 μg/L of As in groundwater were effectively removed in approximately 126-bed volumes, and the spent adsorbents were regenerated with 0.01 mol/L NaOH and maintained the adsorption efficiency after four cycles. This study provides a simple and practical route to fabricate adsorbents for water treatment.

Herein, nickel nanocones and zinc oxide nanosheets were electroplated onto a fabric to produce multifunctional (wearable, stretchable, washable, hydrophobic, and antibacterial) materials with sensing, heating, and supercapacitive properties. All these functionalities are integrated into a one-layered fabric that can be used as a portable intelligent electronic textile for potential application in healthcare monitoring, smart sportswear, and energy storage. Electroplated nickel enhances the electrical conductivity and thus increases the electron charge transfer for supercapacitor applications. The integration of ZnO with the Ni-plated fabric provides pseudocapacitance via redox reactions with the electrolyte. The resistance of the Ni/ZnO fabric changes in response to external stimuli such as temperature and strain. When voltage is applied, the fabric generates heat through Joule heating, demonstrating its potential application as winter sportswear. The superior mechanical durability of the fabric was confirmed through bending and stretching tests. The hydrophobic surface prevents viruses contained in liquid droplets from infiltrating the fabric. In addition, bacterial growth is inhibited because of the antibacterial properties of the Ni/ZnO fabric and because of Joule heating. The one-layered fabric integrated with such multiple functionalities is expected to be applicable in the development of next-generation portable and wearable electronic textiles in various industries.

The drug resistance of chemotherapy is a major challenge to overcome for antineoplastic agents and the reverse of drug resistant is essential for cancer therapy. Herein, we developed a drug delivery system which can simultaneously detect/reverse the drug resistance and perform synergetic treatment of cancer. In this work, we integrated cyanine5 (Cy5) modified miRNA (let-7i) (Cy5-miRNA) and platinum onto nano-graphene oxide (NGO) (30-50 nm) platform to achieve simultaneously detection/reversion of drug resistance and synergetic treatment of cisplatin resistant SKOV3 cells (SKOV3DDP cells). The Cy5-miRNA adsorbed on NGO could selectively bind the drug resistance related mRNA follow by suppress the expression of drug resistance mRNA, and the binding simultaneously induced the release of Cy5-miRNA from the NGO, thus the fluorescence signal of Cy5 recovered and could be used for drug resistance monitoring. Moreover, the miRNA suppressed the Cyclin D1 protein expressions thus reversed the drug resistance. The loaded platinum(IV) (Pt(IV)) was converted to the therapeutic platinum(II) (Pt(II)) in both tumor acidic and reductive environment responsive behavior. NGO furtherly performed photothermal therapy under near infrared (NIR) laser irradiation and enhanced the therapeutic effect. All in all, this nanoplatform realized detection/reversion of the drug resistance as well as synergetic chemical-photothermal treatment of ovarian cancer cells, which holds great promise in the treatment of drug resistant cancer cells.

The article presents the results of mathematical modeling of the initial stage of the combustion of wood and coal particles in conditions corresponding to the combustion chambers of boiler units of thermal power plants. A hypothesis is formulated that describes the sequestration of anthropogenic sulfur oxides (SOx) under the conditions of combustion of mixed fuels based on coal and wood as a result of the interaction of water vapors (formed during the evaporation of interporeal and adsorbed biomass moisture) with SOx with the formation of sulfuric (H2SO4) acid vapors. When these vapors of sulfuric acid H2SO4 interact with iron oxides of the mineral part of the coal. To test the formulated hypothesis, a new mathematical model has been developed for the processes of co-ignition and combustion of wood and coal particles under high-temperature heating conditions. The mathematical model of the ignition process developed by the authors differs from the known ones (published in leading international scientific periodicals on the combustion of solid fuels) by a detailed description of a complex of gas-phase and heterogeneous thermochemical reactions occurring both in the boundary layer of fuel particles and in their porous structure. The mathematical model of the combustion process of wood-coal fuel particles developed by the authors is currently the most detailed in describing the thermophysical, thermochemical and aeromechanical processes occurring both in the fuel particles and in their small vicinity. Multistage kinetic schemes for the oxidation of the main volatile components (methane ‒ CH4, carbon monoxide ‒ CO, hydrogen ‒ H2), as well as the formation of sulfur oxides by means of oxidation of hydrogen sulphide (H2S), released as a result of pyrolysis of the organic part of coal, have been adopted. Based on the results of numerical modeling, the possibility of intensifying the processes of sequestration of sulfur oxides by moistening the wood component of the fuel mixture has been established. It is shown that water vapor can act as an agent adsorbing anthropogenic sulfur oxides, transforming the latter into sulfuric acid vapor, respectively. In turn, the vapors H2SO4 and HNO- 3 can be relatively easily captured by means of condensation. It has been established that for effective SOx capture during co-combustion of coal and biomass, the moisture content of the latter must be at least 5% by weight. The research provides grounds for the conclusion about the possibility of environmentally efficient combustion of coal in the composition of wood-coal fuel composites.

In this work we evaluated the effect of adding Si as sintering additive into SiC for producing air-sintered hollow fiber membranes. According to crystallographic analyses, SiC and Si were converted to SiO2 after sintering at 1350 °C. The addition of 30 wt% of Si into SiC ceramic material promoted the binding of SiC particles and improved the membrane mechanical resistance to 42.25 ± 3.39 MPa after air sintering at 1350 °C. The produced asymmetric ceramic membrane presented a packed pore-network and micro-voids with pore sizes of 1.73 and 5.29 μm, respectively. The filtration of an oil/water emulsion enabled oil retention 98.75 ± 0.95 %. Cake formation was the main fouling occurrence and membrane regeneration with equivalent oil retention and similar steady sate flux was achieved after water cleaning under ultrasound irradiation. Thus, the use of Si as air-sintering aid was favorable for producing Si-bonded SiC hollow fiber membranes with suitable application for oil/water separation.

Metal chalcogenides have been intensively investigated as antibacterial agents due to their unique structures and superior photoactivities. Herein, various structures of copper sulfide (CuS), a metal chalcogenide, such as microspheres (MSs), nanosheets (NSs), and nanoparticles (NPs), were developed in this work for antibacterial applications. A hydrothermal process was utilized to synthesize CuS MSs, CuS NSs, and CuS NPs. Under simulated solar light and near-infrared (NIR) light irradiation, the antibacterial behaviors, reactive oxygen species (ROS) production, and light-driven antibacterial mechanisms of CuS MSs, CuS NSs, and CuS NPs were demonstrated with the bacterium Escherichia coli (E. coli). Bacterial growth curves and ROS generation tests indicated that CuS NSs and CuS NPs had higher light-driven antibacterial activities than that of CuS MSs. ROS of hydroxyl (·OH) and superoxide anion radicals (O2-) were investigated via an electron spin resonance (ESR) spectroscopic analysis by respectively incubating CuS MSs, CuS NSs, and CuS NPs with E. coli under simulated solar light irradiation. Furthermore, E. coli incubated with CuS NPs and CuS NSs showed substantial bacterial degradation after NIR laser irradiation, which was attributed to their photothermal killing effects. Light-driven antibacterial mechanisms of CuS NSs and CuS NPs were investigated, and we discovered that under simulated solar and NIR light irradiation, CuS NSs and CuS NPs produced photoinduced electrons, and the copper ions and photoinduced electrons then reacted with atmospheric moisture to produce hydroxide and superoxide anion radicals and heat, resulting in bacterial mortality.

Light aromatic hydrocarbons are an important by-product of the coal chemical industry. The structure and properties of low molecular compounds (LMCs) embedded in coal are different from those of coal macromolecular skeleton structure, they have important effects on the coal pyrolysis. In this paper, the roles of LMCs on the formation of light aromatics during coal pyrolysis are investigated. The results show that LMCs have little effect on the thermal weight loss behavior of the three coals, but they can influence the carbon structure distribution of coals. The main source of light aromatics from coal pyrolysis is derived from thermal cracking of the coal macromolecular framework. And also the LMCs will be pyrolyzed to generate light aromatics. The total amount of BTEXN from extracts of Shengli coal (SL), Pingshuo coal (PS) and Hexi coal (HX) pyrolysis was 15%, 91%, and 12% of that of raw coal. The alkylbenzenes, naphthalene series, and PAHs can be cracked to form light aromatics. The long chain and cyclic aliphatic compounds can not only provide hydrogen for the free radical fragment of aromatics but also generate light aromatics. And the content of these compounds in the extracts of PS is higher than that of the other two coals. Due to the complexity of the combination between LMCs and coal structure, the extracts are easier to generate light aromatics than LMCs embedded in coal during pyrolysis. Because the composition and content of low molecules in coal with different metamorphic degrees are different, the effects of LMCs on the pyrolysis of low rank coal are more obvious compared with high rank coal.

The formation of uranyl phosphate precipitates is a remediation strategy to limit the mobility of uranium in contaminated soils. However, exposure to organic ligands, like the plant exudate citrate, can remobilize the uranium. The purpose of this study is to provide a more thorough comprehension of citrate-promoted dissolution of a uranyl phosphate mineral, chernikovite [(H3O)(UO2)(PO4)•3H2O], by determining the extent of uranium release from chernikovite at a wide range of citrate concentrations. We have quantified the kinetics of dissolution and proposed potential mechanisms of chernikovite dissolution to gain a better understanding of the fate of uranyl phosphate precipitates in the environment. Batch dissolution and continuously stirred tank reactor (CSTR) experiments indicate that increasing citrate concentrations from 0.1 mM to 50 mM increases the concentration of dissolved uranium. However, at citrate concentrations of 10 mM and greater, the effectiveness of the ligand to enhance the dissolution decreases. Density functional theory modeling and Raman spectroscopy indicate a strong interaction between citrate and the uranyl ions at the surface of the uranyl phosphate. The interaction between citrate and uranyl suggests the formation of an alteration layer of uranyl-citrate surface complexes, which could impede uranium release at citrate concentrations of 10 mM or higher. Together, these results indicate that the citrate-promoted dissolution of chernikovite is a fast reaction that is hindered by a combination of surface saturation and a secondary-phase precipitation reaction at higher concentrations of citrate and reaction times greater than or equal to 72 minutes based on the hydraulic residence time of CSTR experiments. These findings improve our understanding of the stability of uranyl phosphate for use in sequestration of uranium groundwater plumes at contaminated sites.

Magnesium (Mg) has emerged as one of the third-generation biomaterials for regeneration and support of functional bone tissue. Mg is a better choice over permanent implants such as titanium, stainless steel, cobalt-chrome as magnesium is biodegradable and does not require a second surgery for its removal after bone tissue recovery. It also reduces the risk of stress shielding as its elastic modulus is closer to human bone in comparison to permanent implants and other biodegradable metallic implants based on Iron and Zinc. Most importantly, Mg is osteoconductive thus stimulates new bone formation and possess anti-bacterial properties hence reducing the risk of failure due to infection. Despite its advantages, a major concern with pure Mg is its rapid bio-corrosion in presence of body fluids due to which the mechanical integrity of the implant deteriorates before healing of the tissue is complete. Mechanical properties of Mg-based implants can be enhanced by mechanical processing, alloying, and topology optimization. To reduce the corrosion/degradation rate, Mg has been alloyed with metals, reinforced with ceramics, and surface coatings have been applied so that the degradation rate of Mg-based implant matches with that of healing rate of bone tissue. The present review discusses the effect of alloying elements and reinforcing ceramics on microstructure, mechanical, and corrosion properties of Mg-based orthopedic implants. In addition, the biocompatibility of Mg-based alloys, composites, and coatings applied on Mg implants has been highlighted. Further, different methods of fabricating porous implants have been highlighted as making the implant porous facilitates the growth of new bone tissue through the pores.

Commercial CaF2 powder was applied to fabricate transparent CaF2 ceramics by spark plasma sintering under various sintering conditions. The low sintering temperatures and high pressures caused serious carbon contamination, while the soak time had less influence on the carbon concentration in the ceramics. The highest carbon contamination occurred to the CaF2 ceramics sintered at 800 °C. A low sintering pressure suppressed carbon contamination but led to high porosity and large pore size. A high pre-loading pressure led to relatively high porosity and carbon concentration. Furthermore, the relatively fast densification in the edge region of the plates may cause the non-uniform distribution of porosity, thereby affecting the distribution of carbon concentration. The low pre-loading pressure and the high sintering pressure reduced porosity and carbon concentration to obtain dense transparent ceramic with uniform microstructure and high transmittance.

Magnesium (Mg) has been found to be a promising biomaterial candidate for orthopedic implants due to its biocompatibility, biodegradability, and mechanical properties. However, Mg implants suffer from uncontrolled degradation within physiological environment. To this end, this study has investigated effect of incorporation of selective alloying elements (Ca and Zn) within Mg matrix, while gradient porosity was achieved by introducing carbamide. Degradation rate of fabricated scaffolds after immersion in PBS solution was measured by weight loss approach. The study confirmed an overall decrease of the biodegradation of Mg-alloy based sample, owing to formation of intermetallic compounds. While the pH values of the pure magnesium scaffolds in PBS solution were found to be increasing throughout the duration of the study, the pH values of magnesium alloy scaffolds were found to be stabilized after 120 h of immersion time, demonstrating the efficacy of the alloying strategy. Overall, the results reveal that the biodegradation behavior could be tailored by developing engineered magnesium-alloy based bone scaffolds.

The present work deals with the synthesized Manganese (Mn) doped Nickel oxide nanoparticles. Using hydrothermal method, the Manganese (Mn) doped Nickel oxide nanoparticles were synthesized with the concentration ranges from 1 mol% to 2 mol%. The characterization done for the synthesized nanoparticles are X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), DSC spectroscopy and UV visible spectroscopy. The XRD reveals the amorphous nature with the size ranges from 60 nm to 20 nm. The chemical bonding nature and functional group analysis of the prepared material was confirmed by FTIR Spectroscopy. The optical behaviour of the Manganese (Mn) doped Nickel oxide nanoparticle was done using UV–Visible spectroscopy. The antibacterial activity of the prepared nanoparticles was done for both gram negative and gram-positive bacterial strains. The prepared nanoparticles have proven to be promising candidates to be utilized in drug delivery and food packaging applications.

Nitrogen-doped and sulfur, nitrogen co-doped carbon dots (CDs) were synthesized by solid-state, solvent-free, microwave synthesis technique at 250 oC. CDs were synthesized using citric acid as carbon precursor and urea or thiourea as nitrogen and sulfur precursor. The solid-state synthesis produced crystalline nitrogen-doped CDs (N-CDs) and nitrogen/sulfur co-doped CDs (S, N-CDs) with a broad absorption band in the visible region. The photoredox catalytic properties of as-prepared CDs were demonstrated by investigating the model photoreduction of methyl viologen using a 410 nm and 455 nm light-emitting diode (LED). The highest concentration of methyl viologen radical cation were monitored in the presence of N-CDs in comparison with S,N-CDs . The results indicate that nitrogen-doped graphitic CDs feature higher charge extraction for photoredox catalysis in comparison to nitrogen, sulfur co-doped CDs.

Magnesium (Mg), a trace element in the human body, has excellent properties for use as a biodegradable medical implant. Metallic materials such as stainless steel, Co-based alloys, Ti alloys etc. used in biomedical implants. The use of corrodible alloying metals for medical applications has recently been increased. Magnesium as a biodegradable alloy has stupendous properties like elastic modulus, mechanical properties, good biocompatibility, very close to bone properties and helps in bone remodelling or ossification. The review study focuses on the degradation behavior of Mg-based alloys, influenced by alloying elements to increase resistance to corrosion, mechanical properties and bioactivity. This study reveals that the degradation rate can be controlled by lowering the corrosion rate through proper alloying by elements such as Zr, Sr, Mn, Ca, Zn, Al and rare earth elements and enhanced biocompatibility. The analysis has been discussed for cardiovascular, orthopaedic, tissue engineering, and therapeutic implant applications focused on Mg-based alloys.

The objective of present review is to critically analyze the induced surface characteristics and in-vitro & in-vivo analysis of Titanium and Ti-alloys based implants after surface modification through various techniques. The modified surfaces have nano-pores, micro cracks and recast layers which affects the properties of cell adhesion, osseointegration, cell growth and hemocompatibilty. EDM/WEDM have great potential for surface modifications of solid Ti and Ti-alloys for their use in the orthopaedic implants having better outcomes than other techniques. However, the stress shielding between the implants and bone is a major challenge in tissue engineering due to differences in their elastic moduli. The porous and perforated implants fabricated using micro-drilling, SEBM and SLM provide favorable solution to this problem. Therefore, through this literature review, the influence of adavance manufacturing processes on the biocompatibility, corrosion resistance and mechanical properties of Ti and Ti based alloys through in-vivo and in-vitro studies has been discused and reviewed.

In this work, we propose lateral voltage as a new input for use in artificial lipid bilayer systems in addition to the commonly used transmembrane voltage. To apply a lateral voltage to bilayer lipid membranes, we fabricated electrode-equipped silicon and Teflon chips. The Si chips could be used for photodetector devices based on fullerene-doped lipid bilayers, and the Teflon chips were used in a study of the ion channel functions in the lipid bilayer. The findings indicate that the lateral voltage effectively regulates the transmembrane current, in both ion-channel-incorporated and fullerene-incorporated lipid bilayer systems, suggesting that the lateral voltage is a practicable and useful additional input for use in lipid bilayer systems.

Modulating the activation state and degree of macrophages still remains as a challenge for the topographical design of Ti-based implants. In this work, micro/nano-structured coatings were prepared on Ti substrates by micro-arc oxidation (MAO) and subsequent hydrothermal (HT) treatment. By varying the HT conditions, plate-like nano-structures with an average length of 80, 440 or 780 nm were obtained on MAO-prepared micro-topographical surfaces. Depending on the dimensional features of nano-plates, the specimens were noted as Micro, Micro/Nano-180, Micro/Nano-440 and Micro/Nano-780, respectively. The in vitro results showed that the activation state and degree of macrophages could be effectively modulated by the micro/nano-structured surfaces with various dimensional features. Compared to the Micro surface, the Micro/Nano-180 surface activated both M1 and M2 phenotype in macrophages, while the Micro/Nano-440 and Micro/Nano-780 surfaces polarized macrophages to their M1 phenotype. The activation degree of M1 macrophages followed the trend: Micro

Chromium (Cr), Copper (Cu), Cobalt (Co), Ferrous (Fe) and Nickel (Ni), the High Entropy Alloys were mixed to form an alloy with different combination of cobalt(X = 0.2,). A die was made of OHNS (Oil Hardened Nickel Steel). The alloyed powder was loaded into the die and a load of 13KN was applied. Universal Testing Machine (UTM) was used for the load application. After pressing, the specimen was kept inside the Muffle Furnace for heating at 800 °C for sintering. After heating, the surface of the specimen was smoothened by roughing. The specimen was subjected to wear test in Pin on Disc Machine. The weight of the specimen was noted, before and after the wear test. Wear rate of the specimen was calculated.

High chromium white cast iron (HCCI) is used in the grinding rolls of pulverizers of the thermal power plants for crushing coal into fine particles. Currently, there is a sharp depletion of high grade coal, thereby, increasing the need for utilization of coal with higher mineral content. This usage of high mineral coal poses a problem of enhancing the wear rate of grinding media. This increases the demand for development of materials which pulverize coal to have longer service life. The present work provides insight into the effect of alloying additions of V, Ti and B to HCCI on the dry sliding wear behavior. Dry sliding wear behavior was studied using pin on disc method with speeds of 159 RPM, 319 RPM, 478 RPM under different load conditions of 10 N, 20 N and 30 N. Some of the alloys have higher coefficient of friction and exhibit higher wear rate while others have lubricating effect and exhibit lower wear rate. The medium speed of 319 RPM and 30 N load exerts the maximum wear rate on most of the alloys. This work also provides comparison of the wear resistance offered due to alloying additions to HCCI with Ni-hard iron. The role of secondary carbides in enhancing wear resistance is also discussed.

The substance properties were enhanced gradually through cryogenic treatment. The current experimental investigation has reported the enhanced substance properties of Haynes alloy. The substance properties of Haynes 214 alloy has not been increased by conventional technique. It has better properties and it consists of nickel, chromium, aluminium and iron based alloy. In this process, the alloys were treated to −190 °C. The cryogenic treatments were performed with the help of cryo processor. The alloy properties of hardness and wear rate were estimated with respect to the different control factors. Taguchi approach was utilized to determine the desired response factors. The effect of factors and its involvement have been investigational through variance test.

Magnesium (Mg) and its alloys have emerged as a favored candidate for bio-regenerative medical implants due to their superior biocompatibility, biodegradability and the elastic modulus close to that of human bone. Unfortunately, the rapid and uncontrollable degradation rate of Mg alloys in chloride-rich body microenvironments limits their clinical orthopedic applications. Recently, Calcium Phosphate (Ca-P) biomaterials, especially Hydroxyapatite (HA), have been broadly applied in the surface functional modification of metal-based biomaterials attributed to their excellent bioactivity and biocompatibility. Hydrothermal modification of Ca-P coatings on Mg alloys has been extensively exploited by researchers for its significant superiorities in controlling coating structure and improving interfacial bonding strength for better osseointegration and corrosion resistance. This work focuses on the up-to-the-minute advances in Ca-P coatings on the surface of Mg and its alloys via hydrothermal methods, including the strategies and mechanisms of hydrothermal modification. Herein, we are inclined to share some feasible and attractive hydrothermal surface modification strategies. From the perspectives of hydrothermal manufacturing technique innovation and coating structure optimization, we evaluate how to foster the corrosion resistance, coating bonding strength, osseointegration and antibacterial properties of Mg alloys with Ca-P coatings synthesized by hydrothermal method. The challenges and future perspectives on the follow-up exploration of Mg alloys for orthopedic applications are also elaborately proposed.

Hexavalent chromium [Cr(VI)] is a heavy metal pollutant in the environment released through leather tanning. In this context, the present study was envisaged to isolate and identify chromium reducing bacteria in order to employ them towards detoxification of chromium. In general, bacteria are ecofriendly and cost-effective which can be efficiently used in bioremediation processes. The collected tannery effluents yielded considerable Bacillus species. These isolates demonstrated well for their resistance which showed exceptional Cr(VI) reduction within 48 h under aerobic conditions. Mostly, chromium resistance confers through Chromate transporters which involves metabolic reduction of toxic Cr(VI) to non-toxic Cr(III). Distribution of chr genes in Bacillus species were identified from their genome through UniProt. Treatment of raw tannery effluent employing these isolates individually or as a consortia reduced Cr(VI) significantly. Thus, these bacterial strains, could evolve as a potential organisms to reduce toxic Cr(VI) to its non-toxic Cr(III) form in chromium contaminated sites.

The present work seeks to develop a novel and systematic approach to quantifying the repeatability of textured surfaces, a relevant property for several technological fields. Specifically, aluminum alloy and stainless steel specimens were subject to nanosecond pulsed laser texturing to produce arrays of ablation craters in a typical configuration employed to improve wettability and tribological performance. Feature repeatability was firstly assessed in terms of crater volume and interfacial area, after which an additional parameter was developed based on the Pearson's Correlation Coefficient (PCC). Within the tested laser parameter range, the crater volume exhibited highest repeatability in the high energy dose regime on aluminum alloy specimens, while the crater volume was more repeatable in the low energy dose regime on stainless steel specimens. This difference was attributed to the development of an oxide ring surrounding the craters on stainless steel at high energy dose. This outcome was confirmed through analysis of the point-to-point repeatability, where process repeatability was determined for different portions of the ablation craters.

Magnesium’s lightweight property made it an intriguing element as a component in automobiles and aerospace, as well as its biodegradability to be used in orthopaedic. However, magnesium is prone to corrosion that limits its application. To fully utilize magnesium, corrosion protection methods should be established. Various techniques have been used to protect magnesium and its alloys from corrosion, including coating. Coating provides a barrier to prevent corrosive electrolytes from reacting with magnesium substrates and initiate Mg dissolution. This study reviewed several surface coating methods used for Mg alloys, such as chemical conversion coating, anodizing, plasma electrolytic oxidation (PEO), organic coating, cold spraying, and layered double hydroxide (LDHs). The composite coatings, for example, combined PEO-hybrid sol–gel coating, provide dense barrier, thus better corrosion protection performance than conventional single PEO layer. The newer advanced self-healing coatings which incorporate inhibitors into the layer, either directly added or within carriers, are considered in this study.

This study presents the synergy of high ash coal with different biomass when blended in different ratios for co-gasification using a fluidized bed gasifier. The moisture, CO2, oxygen, hydrogen and numerous other compounds have synergetic effects on the co-gasification because of affinity to heat and prone to reaction. The mineral constituents, discrete mineral species and ion-exchangeable elements present in coal, biomass and bottom ash residue have been identified by XRD, XRF, FTIR and SEM-EDX. The catalytic effects of mineral, major oxides, halides and chlorites content on co-gasification have been assessed. The mineral (e.g. calcite, dolomite, hematite, etc.) present in the high ash coal and biomass plays a catalytic role. Other minerals (e.g. quartz, sulfide, kaolinite and phosphates) negatively influence co-gasification and product gas composition. The positive relationship of CaO, MgO and Fe2O3 with CCE, CGE and increasing heat values also supports major oxides catalytic role. The blend of press mud and high ash coal has given better results due to more Ca, K, Mg and Na elements. SEM microphotographs reveal catalytic effects at the micro-level, indicated by the extensive cracking of hydrocarbon compounds. The empirical models proposed for estimation of catalytic effects of minerals on co-gasification.

Magnesium (Mg) as a trace element of human body possesses excellent properties to be a biodegradable medical implant. It has elastic modulus and density almost equal to human bone, excellent biocompatibility and osseointegration; also it shows negligible toxicity in body fluids. Corrosion and mechanical characteristics of Mg and its alloys could be increased by optimized alloying, with reasonable biocompatibility. Surface coatings enhance the surface characteristics of Mg alloys and reduce the degradation rate. In this review the effects of alloying and surface coatings of Mg alloys are summarized on account of the corrosion behaviour, degradation rate and biocompatibility. The combination of alloying and surface coating could be an excellent option for biomedical implants because alloying tackle the hydrogen evolution, corrosion problems and enhance biocompatibility; then coating helps to control the degradation rate of Mg alloys as a result reduces the loss of mechanical properties.

Traditional hard/soft template approaches to hollow structures suffer from tedious procedures and time-consuming. Compare to these methods, self-template approaches usually gain advantages of step-economy. Herein, solid spherical Ni-glycolate/Ni microspheres were initially synthesized by reacting nickel (II) with ethylene glycol at high temperature. The source of nickel (II) has determinable impact on the formation of Ni-glycolate/Ni. Specially, nickel acetate as sources yielded Ni-glycolate/Ni, while nickel nitrate as precursor cannot. The plausible reason for this result can be attributed to the different acidity of the system caused by the dissolution of nickelacetate and nickel nitrate. By reacting with thioacetamide (TAA) under solvothermal condition and heat treatment, the Ni-glycolate/Ni microspheres were further employed as self-template for direct the formation of hollow NiS microspheres. The driving force for converting Ni-glycolate/Ni into hollow NiS could be attributed to Kirkendall effect resulted from the different diffusion rates of nickel ions (from Ni-glycolate/Ni) and sulfur ions from the decomposition of TAA. When applied as electrode material of supercapacitors, the formed hollow NiS microspheres exhibited a specific capacitance of 1674 F/g at 1 A/g with excellent rate capability and cycling performance. The corresponding asymmetric device of NiS//AC delivered a high energy density of 43.3 Wh/kg at the power density of 850.3 W/kg. These achievements pave innovative synthetic approach to hollow structures for many other practical applications.

Titanium and its alloys have become the ultimate choice for the next era of orthopedic implants such as Hip stem, acetabular cup, and orthopedic accessories. This critical review presents the challenges in fabrication and solutions (surface engineering) to successfully implement Ti alloys in biomedical industries successfully. A critical review on the application surface modification of Ti-alloy using thermal spray coatings has been reported. Hydroxyapatite (HA) has been used as vital biological coating-materials for load-bearing implant applications, mostly hip implants. Moreover, the research papers also present bibliometric analysis that reveals the researcher's information and their affiliation for significant contribution in the area of Ha-coatings on Ti-alloy using plasma spray techniques.

To increase the agricultural production, nano fertilizers have allowed the development of new technologies. In this study, zinc oxide nanoparticles (ZnO-NPs), iron oxide nanoparticles (FeO-NPs) and magnesium oxide nanoparticles (MgO-NPs) have been prepared and applied on the medicinal plants (Caesalpinia bonducella) to increase the yield, nutrient and chlorophyll contents. This study intended to compare the impacts of synthesised NPs with the control plants and their conventional fertilizers such as ZnSO4·7H2O (Zn-bulk), FeSO4·7H2O (Fe-bulk) and MgSO4·7H2O (Mg-bulk). All fertilizers were applied in a completely randomized design including six treatments and three replications of each treatment by using a combination of seed priming method and soil mixing process. Moreover, the NPs were also compared for the best gaining of results. The concentrations selected for applications were 10, 20, 30, 40 ppm for iron and magnesium fertilizers and 25, 50, 75, 100 ppm for zinc-based fertilizers. The results indicated the increase in morphological parameters of the plants of 28–50% by the application of conventional fertilizers while 50–93% by NPs application as compared to control plants. Furthermore, the increase in chlorophyll contents was 5–28% with conventional fertilizers while 30–80% in case of NPs application than control plants. The obtained results indicate that the best increase in growth, nutrient and chlorophyll contents of plants were achieved at the dose concentrations of 40 ppm for Mg and Fe fertilizers and 100 ppm for Zn fertilizers. The comparative study of NPs showed that the highest growth and yield was obtained by the use of ZnO-NPs in comparison to others. Finally, it is worth highlighting that NPs have a huge potential to increase the productivity of crops if applied in optimal concentrations.

It has become known that copper alloys are commonly used in heat exchangers and other marine industries. Although copper-nickel alloys have better properties than copper-zinc alloys in general, they are very expensive. The current research aims to give the alloy to give brass alloy (the cheapest alloy) superior properties in order to improve its performance and prolong the life of its use in the most important parts of the heat exchangers (pipes). Casting and heat treatment elements were used, and casting was carried out in a manner that ensures that the grains were softened to improve the properties. Tests were conducted to evaluate the performance of alloys such as hardness, oxidation and thermal shock. The effect of temperature and thickness of the oxide layer on the oxidation behavior was also studied. The results showed a significant increase in the thermal shock resistance, a positive change in the oxidation behavior, in addition to a significant improvement in the plasticity and adhesion of the oxide layer.

Magnesium is one of the largely available elements in the earth's crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and its alloys in various applications pertaining to industrial sector, automobiles, aerospace and biomedical. Since magnesium is a highly reactive metal, it is prone to higher rate of corrosion as compared to its counterparts. Thus, it is essential to analyze the corrosion behavior of magnesium and its alloys in its applications. An appropriate process is to be followed in the design and development of magnesium alloys which overcome the limitations of magnesium and enhance the desired material properties in accordance to their applications. This review paper summarizes the importance of magnesium and its material properties. The influence of various alloying elements on the mechanical properties of magnesium is reviewed. The broad classification of Mg alloys and their behavioral trends are detailed. The corrosion behavior of magnesium and the influence of corrosion products on the material characteristics of magnesium, in aqueous medium, are discussed. The manufacturing techniques of magnesium alloys along with the secondary techniques are also covered. The various applications and the limitations of magnesium in these applications are covered. A complete section is dedicated towards detailing the recent trends of magnesium (Mg) alloys, i.e., the biodegradable nature and applications of Mg alloys. The influence of biocorrosion on Mg alloys and techniques to overcome it have been deliberated. This paper provides a thorough review on recent developments of magnesium with respect to engineering applications.