Energy Dispersive X-ray Elemental Analysis Research Articles

Kinetics and Nanoparticle Catalytic Enhancement of Biogas Production from Wastewater Using a Magnetized Biochemical Methane Potential (MBMP) System

This study presents magnetized nanoparticles (NPs) as a catalyst to accelerate anaerobic digestion (AD) potential for clean and ecofriendly energy (biogas) from wastewater settings. The effects of iron oxides (Ms) and aluminum sulphate (Alum) were investigated using two chronological experiments: (i) the Jar test technique to generate residue slurry as organic fertilizer potential and (ii) a magnetized biochemical methane potential (MBMP) system for biogas production at mesophilic conditions for 21 days. X-ray diffraction and Fourier Transform Infrared spectroscopy were carried out to establish the Ms Crystallite and active functional groups respectively. Scanning electronic microscopy coupled with energy dispersive X-ray spectrometer and elemental analysis were used to track and confirm NPs inclusion after the post-AD process. Coagulation at 50 mg/L and magnetic exposure time of 30 min showed above 85% treatability performance by Ms as compared to 70% for Alum. Owing to the slow kinetics of the AD process, additional NPs content in the digesters coupled with an external magnetic field improved their performance. Cumulative biogas yields of 1460 mL/d > 610 mL/d > 505 mL/d for Ms > Control > Alum respectively representing 80% > 61% > 52% of CH4 were attained. The modified Gompertz model shows that the presence of NPs shortens the lag phase of the control system with kinetics rate constants of 0.285 1/d (control) to 0.127 1/d (Ms) < 0.195 1/d (Alum).

Surface Modification of TiO2 nanoparticles using Conducting Polymer Coating: Spectroscopic, Structural, Morphological Characterization and Interaction with Dye Molecules

In the present research, the surface of titanium dioxide nanoparticles was modified using a conducting polymer coating in the presence of an oxidizing agent. The structure and morphology of as-modified polypyrrole-coated titanium dioxide nanoparticles were investigated by X-ray diffraction and Transmission electron microscopy techniques. The nitrogen adsorption-desorption performance of as-modified polypyrrole-coated titanium dioxide nanoparticles were also investigated to revealed its details of specific surface area, structural properties and pore geometries. The polypyrrole coated titanium dioxide nanoparticles were utilized for adsorption of hazardous anionic dye (Congo red) from aqueous solution. The adsorption of Congo red dye onto polypyrrole-coated titanium dioxide nano-adsorbent was confirmed by advanced instrumental techniques such as Fourier transform infrared spectroscopy, Field emission scanning electron microscopy, Energy dispersive x-ray spectroscopy and Elemental mapping analysis. The adsorption performance of polypyrrole-coated titanium dioxide nano-adsorbent was evaluated by batch experimental technique. The effects of different parameters such as pH, contact time, and dose on the adsorption tests were also determined. The highest adsorption of Congo red dye (98.75%) was achieved at pH ˜3 using 50 mg of polypyrrole-coated titanium dioxide nano-adsorbent. The reusability of polypyrrole-coated titanium dioxide nano-adsorbent was also evaluated by several adsorptions-desorption cycles. The reusability result demonstrated excellent adsorption potential of polypyrrole-coated titanium dioxide nano-adsorbent for water-treatment application.

Chemical composition, surface roughness, and ceramic bond strength of additively manufactured cobalt-chromium dental alloys

Statement of problemSelective laser melting (SLM) additive manufacturing (AM) technology is a current option to fabricate cobalt-chromium (Co-Cr) metal frameworks for dental prostheses. However, the Co-Cr alloy composition, surface roughness, and ceramic bond strength values that SLM metals can obtain are not well-defined. PurposeThe purpose of this in vitro study was to compare the chemical composition, surface roughness, and ceramic shear bond strength of the milled and SLM Co-Cr dental alloys. Material and methodsA total of 50 disks of 5 mm in diameter and 1 mm in thickness were fabricated by using subtractive (control group) and AM with each of following SLM providers: SLM-1 (EOS), SLM-2 (3D systems), and SLM-3 (Concept Laser). The milled disks were airborne-particle abraded with 100-μm aluminum oxide particles. All the specimens were cleaned before surface roughness (Ra), weight (Wt%), and atomic (At%) percentages were analyzed. Three-dimensional profilometry was used to analyze the topographical properties of the surface parameters Ra (mean surface roughness). The chemical composition of Co-Cr alloy specimens was determined by using energy dispersive X-ray (EDAX) elemental analysis in a scanning electron microscope (SEM). Thereafter, the specimens were bonded to a ceramic (Dentine A3 and Enamel S-59; Creation CC) interface. Specimens were stored for 24 hours at 23 °C. The bond strength of the SLM-ceramic interface was measured by using the macroshear test (SBT) method (n=10). Adhesion tests were performed in a universal testing machine (1 mm/min). The Shapiro-Wilk test revealed that the chemical composition data were not normally distributed. Therefore, the atomic (At%) and weight percentages (Wt%) were analyzed by using the Kruskal-Wallis test, followed by pairwise Mann-Whitney U tests between the control and AM groups (AM-1 to AM-4). However, the Shapiro-Wilk test revealed that the surface roughness (Ra) and ceramic bond strength data were normally distributed. Therefore, data were analyzed by using 1-way ANOVA, followed by the post hoc Sidak test (α=.05). ResultsSignificant differences were obtained in Wt%, At%, and Ra values among the Co-Cr alloys evaluated (P<.05). Furthermore, the control group revealed significantly lower mean ±standard deviation Ra values (0.79 ±0.11 μm), followed by AM-3 (1.57 ±0.15 μm), AM-2 (1.80 ±0.43 μm), AM-1 (2.43 ±0.34 μm), and AM-4 (2.84 ±0.27 μm). However, no significant differences were obtained in the metal-ceramic shear bond strength among the different groups evaluated, ranging from mean ±standard deviation 75.77 ±11.92 MPa to 83.65 ±12.21 MPa. ConclusionsCo-Cr dental alloys demonstrated a significant difference in their chemical compositions. Subtractive and additive manufacturing procedures demonstrated a significant influence on the surface roughness of the Co-Cr alloy specimens. However, the metal-ceramic shear bond strength of Co-Cr alloys was found to be independent of the manufacturing process.

Fe/Mg-Modified Carbonate Apatite with Uniform Particle Size and Unique Transport Protein-Related Protein Corona Efficiently Delivers Doxorubicin into Breast Cancer Cells.

Breast cancer is the abnormal, uncontrollable proliferation of cells in the breast. Conventional treatment modalities like chemotherapy induce deteriorating side effects on healthy cells. Non-viral inorganic nanoparticles (NPs) confer exclusive characteristics, such as, stability, controllable shape and size, facile surface modification, and unique magnetic and optical properties which make them attractive drug carriers. Among them, carbonate apatite (CA) particles are pH-responsive in nature, enabling rapid intracellular drug release, but are typically heterogeneous with the tendency to self-aggregate. Here, we modified the nano-carrier by partially substituting Ca2+ with Mg2+ and Fe3+ into a basic lattice structure of CA, forming Fe/Mg-carbonate apatite (Fe/Mg-CA) NPs with the ability to mitigate self-aggregation, form unique protein corona in the presence of serum and efficiently deliver doxorubicin (DOX), an anti-cancer drug into breast cancer cells. Two formulations of Fe/Mg-CA NPs were generated by adding different concentrations of Fe3+ and Mg2+ along with a fixed amount of Ca2+ in bicarbonate buffered DMEM (Dulbecco’s Modified Eagle’s Medium), followed by 30 min incubation at 37 °C. Particles were characterized by turbidity analysis, z-average diameter and zeta potential measurement, optical microscopy, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), flame atomic absorption spectroscopy (FAAS), pH dissolution, drug binding, cellular uptake, thiazolyl blue tetrazolium bromide (MTT) assay, stability analysis, and protein corona study by LCMS (Liquid chromatography-mass spectrometry). Both formulations of Fe/Mg-CA displayed mostly uniform nano-sized particles with less tendency to aggregate. The EDX and FAAS elemental analysis confirmed the weight (%) of Ca, Fe and Mg, along with their Ca/P ratio in the particles. A constant drug binding efficiency was noticed with 5 μM to 10 μM of initial DOX concentration. A pH dissolution study of Fe/Mg-CA NPs revealed the quick release of DOX in acidic pH. Enhancement of cytotoxicity for the chemotherapy drug was greater for Fe/Mg-CA NPs as compared to CA NPs, which could be explained by an increase in cellular internalization as a result of the small z-average diameter of the former. The protein corona study by LCMS demonstrated that Fe/Mg-CA NPs exhibited the highest affinity towards transport proteins without binding with opsonins. Biodistribution study was performed to study the effect of DOX-loaded Fe/Mg-CA NPs on the tissue distribution of DOX in Balb/c 4T1 tumor-bearing mice. Both formulations of Fe/Mg-CA NPs have significantly increased the accumulation of DOX in tumors. Interestingly, high Fe/Mg-CA NPs exhibited less off-target distribution compared to low Fe/Mg-CA NPs. Furthermore, the blood plasma analysis revealed prolonged blood circulation half-life of DOX-loaded low and high Fe/Mg-CA NPs compared to free DOX solution. Modifying CA NPs with Fe3+ and Mg2+, thereby, led to the generation of nano-sized particles with less tendency to aggregate, enhancing the drug binding efficiency, cellular uptake, and cytotoxicity without hampering drug release in acidic pH, while improving the circulation half-life and tumor accumulation of DOX. Therefore, Fe/Mg-CA which predominantly forms a transport protein-related protein corona could be a proficient carrier for therapeutic delivery in breast cancer.

A General Protocol for Electrospun Non-Woven Fabrics of Dialdehyde Cellulose and Poly(Vinyl Alcohol).

In the past two decades, research on electrospinning has boomed due to its advantages of simple process, small fiber diameter, and special physical and chemical properties. The electrospun fibers are collected in a non-woven state in most cases (electrospun non-woven fabrics, ESNWs), which renders the electrospinning method an optimum approach for non-woven fabric manufacturing on the nano-scale. The present study establishes a convenient preparation procedure for converting water-soluble dialdehyde cellulose (DAC) into DAC-based electrospun non-woven fabrics (ESNWs) reinforced with poly(vinyl alcohol) (PVA). The aldehyde content, which was quantified by colorimetry using Schiff’s reagent, was 11.1 mmol per gram of DAC, which corresponds to a conversion yield of ca. 90%. DAC is fully water-soluble at room temperature between 10 and 30 wt%, and aqueous solutions turn into hydrogels within 24 h. To overcome gelation, NaHSO3, which forms bisulfite adducts with aldehyde functions, was added to the DAC and its concentration was optimized at 1 wt%. The electrospun (ES) dope containing 5 wt% DAC, 5 wt% PVA, and 1 wt% NaHSO3 in an aqueous solution was successfully transformed into ESNW, with an average fiber diameter of 345 ± 43 nm. Post-spinning treatment with excess hexamethylene diisocyanate was performed to insolubilize the ESNW materials. The occurrence of this chemical conversion was confirmed by energy-dispersive X-ray elemental analysis and vibrational spectra. The cross-linked DAC/PVA ESNW retained its thin fiber network upon soaking in distilled water, increasing the average fiber diameter to 424 ± 95 nm. This suggests that DAC/PVA-ESNWs will be applicable for incorporation or immobilization of biologically active substances.

Ferromagnetic activated carbon from cassava (Manihot dulcis) peels activated by iron(III) chloride: Synthesis and characterization

Ferromagnetic activated carbon (FAC) was prepared through impregnation of cassava peel with FeCl3 (3.75%) solution and pyrolyzed at 800 °C. Samples were characterized using iodine number, methylene blue number, X-ray fluorescence, Fourier transformation infrared, X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled to energy dispersive X-ray spectroscopy, elemental analysis and N2 adsorption for surface area determination. The proximate analysis of cassava peel showed that the moisture content, fixed carbon, ash content, and the volatile matter were 3.52%, 82.97%, 4.97%, and 8.54%, respectively. The prepared FAC had a BET surface area of 405.9 m2/g, pore size of 2.03 nm and total pore volume of 0.11 cm3/g. The SEM analysis showed the presence of both micro and mesopores on the FAC sample. The XRD pattern of FAC showed the presence of characteristic peaks of magnetite–maghemite, confirming that the prepared material is ferromagnetic. According to the experimental results, the cassava peels are considered as appropriate raw material for FAC preparation.

Vanadium Oxide Nanofibers: Synthesis and Research on Functional Properties

Aim: Vanadium oxide nanofibers have been manufactured by the sol–gel electrospinning method followed by the thermal treatment in air and argon. Materials and Methods: The samples are characterized by optical, laser confocal and scanning electron microscopy, energy-dispersive X-ray elemental analysis, X-ray diffraction, cyclic voltammetry, and electrical conductivity measurements. Results: The obtained VO2 nanofibers demonstrate the semiconductor-to-metal phase transition. Also, the vanadium pentoxide nanofibers are examined as electrode materials for rechargeable Li-ion batteries.

Effective adsorption of metronidazole antibiotic from water with a stable Zr(IV)-MOFs: Insights from DFT, kinetics and thermodynamics studies

The adsorptive removal of antibiotics, emerging organic pollutants in water is very important but challenging. In this work we report a series of eight water stable metal-organic framework (MOFs), which are methodically screened for the removal of metronidazole (MNZ) from water. It was found that two isostructural Zr(IV)-MOFs (UiO-66 and UiO-66-NH2) showed adsorption capacities of around 200.2 mg g−1 and 265.5 mg g−1, respectively, which are higher than the experimental values of reported porous materials used for MNZ removal so far. The MOFs were characterized by Powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy, Thermogravimetric analysis (TGA), Scanning electron microscope (SEM), Energy-dispersive X-ray elemental analysis (EDX), BET isotherm, UV–vis (UV–vis) spectrophotometer and NICOMP™ 380 ZLS. The effects of various parameters including time, concentration, temperature and pH were investigated. The adsorption mechanism of UiO-66-NH2 for MNZ has also been explored through computational simulations. The results showed that MNZ molecules are mainly locate at around the -NH2 functional groups in pore surfaces of UiO-66-NH2, with the increase of molecular level of the amino groups, the affinity of the framework to MNZ could be significantly increased. The results demonstrated that highest adsorption uptake by UiO-66-NH2 was attributed to -NH2 functional group including with (hydrogen bonding interactions, electrostatic interaction and larger pHpzc). The adsorption process of the two MOFs fitted the pseudo-second-order kinetic model and Langmuir isothermal model, whilst the adsorption was endothermic, with the confirmation by thermodynamic studies.

Fabrication of a sensitive and fast response electrochemical glucose sensing platform based on co-based metal-organic frameworks obtained from rapid in situ conversion of electrodeposited cobalt hydroxide intermediates

In this study, for the first time, we reported a fast and facile three-step in situ strategy for direct controllable growth of the Co3(BTC)2 MOFs thin films on the GCE, through the rapid conversion of the electrodeposited Co(OH)2 nano-flakes on rGO/GCE, to crystalline rectangular bar-shape structures of MOFs. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and elemental mapping analysis used to the structural and morphological characterization of the well-synthesized MOFs. The as-prepared Co3(BTC)2 MOFs were used to construct a non-enzymatic sensing platform for determining the glucose in alkaline solution. The designed electrode demonstrated two wide linear dynamic range of 1 μM - 0.33 mM and 0.33 mM–1.38 mM with high sensitivity of 1792 μA mM−1 cm−2 and 1002 μA mM−1 cm−2, respectively, good repeatability and reproducibility, high selectivity against interference species and good poisoning resistance against chloride ions and a low detection limit of 0.33 μM (S/N = 3). Finally, the application of the proposed sensor for the determination of glucose in the human blood serum samples was investigated and results showed excellent recoveries, which confirmed that the fabricated sensor can act as a reliable and sensitive platform for biological and clinical samples analysis.

Incorporation of Co2+ in CdS quantum dots for solar cell applications

Spin coating and successive ionic layer adsorption and reaction (SILAR) method were adopted to deposit commercial TiO2 (Degussa-P25), un-dopedCdS and Co2+-doped CdS quantum dots (QDs). Characteristic peak for CdS, TiO2and FTO were observed in powder X-ray diffraction pattern of the prepared samples. Co2+-doping was confirmed through energy dispersive X-ray spectroscopy and elemental mapping analysis. Spherical shaped morphology was observed in field emission scanning electron microscopy (FE-SEM). Measured size of CdS is ~8 nm and the TiO2 is ~20 nm through HR-TEM imaging. The maximum absorption range was observed as 570 nm for 3% Co2+-doped CdS QDs. Power conversion efficiency of un-doped CdS and 3% Co2+-doped CdS QDs were 0.54% and 1.21% respectively. It indicated that up to 3% Co2+-doping in CdS QDs leads to remarkable enhancement in the optical absorption, absorption range and photovoltaic performance under chosen experimental conditions.

One Pot Synthesis of Luminescent Polyoxometalate Supported Transition Metal Complex and biological evaluation as a potential larvicidal and anti-cancer agent

Silicotungstate cluster coordinated organic-inorganic hybrid material [Cu(dmbpy)]2 [SiW12O40]·8H2O (1) known as polyoxometalate supported transition metal complex (POM-TMC) was synthesized simply in a one-pot reaction. The yield of the compound was significantly higher than the previous report. Larvicidal activity of 1 was investigated against dengue vector Aedes aegypti. A series of morphological changes in the mosquito larva was observed on exposure to different concentrations of the title compound. The total disintegration of the larva was observed at 50 μg/mL. In addition to the larvicidal activity, compound 1 exhibits anti-proliferative activity against the A375 human skin cancer cell line. PXRD pattern stimulated from single-crystal X-ray data was harmonized with PXRD of 1. Additionally, 1 was characterized by UV–Visible, Fluorescence, UV-DRS, FT-IR and Cyclic Voltammetry. Morphology of 1 was analyzed by Scanning Electron Microscopy (SEM). Composition of 1 was analyzed by Energy Dispersive X-ray SEM-EDX and Elemental analysis.

Lanthanum/Gemini surfactant-modified montmorillonite for simultaneous removal of phosphate and nitrate from aqueous solution

La3+-exchanged bentonite (Phoslock®) is a well-known adsorbent for phosphate, but it is incapable of simultaneously removing nitrate from aqueous solution. In this study, montmorillonite (Mt) was modified stepwise by lanthanum and a cationic gemini surfactant for co-adsorption of phosphate and nitrate. X-ray diffraction patterns revealed that lanthanum existed as LaCO3OH and the gemini surfactant intercalated into the interlayer space of Mt. The contents of lanthanum and gemini surfactant in obtained nanocomposite (LaOMt) were estimated using energy dispersive X-ray spectroscopy and elemental analysis, which are 0.163 and 0.435 mmol/g, respectively. Based on Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, uptake of phosphate was attributed to ligand exchange with hydroxyl and electrostatic attraction on positively charged LaCO3OH, and that of nitrate mainly resulted from the ion exchange with bromide ion and interactions with –R4N+ groups released from Mt layers. The estimated adsorption capacities of LaOMt to nitrate and phosphate were 0.84 and 0.39 mmol/g, respectively. Adsorption of phosphate was negligibly affected by nitrate, but the presence of phosphate facilitated the hydration of LaOMt and improved nitrate uptake. Compared with commercial Phoslock®, LaOMt demonstrated comparable adsorption performance in terms of phosphate removal. Considering the simultaneous uptake of nitrate and stable adsorption performance when ubiquitous anions coexisted, LaOMt is a promising adsorbent for remediation of phosphate and nitrate contaminated wastewater.

Characterization of functionalized multiwalled carbon nanotubes and comparison of their cellular toxicity between HEK 293 cells and zebra fish in vivo.

Carbon nanotubes (CNTs) hold tremendous potential due to their unique and modifiable properties. Their robust biological applications necessitate minimizing their cytotoxicity and increasing the solubilization. In the present manuscript, we have functionalized multiwalled carbon nanotubes (MWCNTs) using defect functionalization methodology to covalently bind carboxy and amino groups on their walls. This functionalization was reassured through fourier-transform infrared spectroscopy (FTIR), energy dispersive x-ray analysis (EDX), elemental and field emission scanning electron microscopy (FE-SEM) analysis. The observations demonstrated that addition of carboxy as well as amino groups on MWCNTs, besides enabling MWCNTs solubilization also significantly ameliorated the cytotoxicity and the oxidative stress in comparison to pristine MWCNTs. It is envisaged that changes in agglomeration of the functionalized MWCNTs and the acquired surface charge is the reason for the reduction of cytotoxicity. Zebra fish embryo model test system employed for in vivo analysis of the MWCNTs showed no significant toxicity on account of any nanoparticle tested pointing towards intrinsic mechanisms in place for deterring the damage in complex organisms. Overall, the observations besides pointing towards functionalized MWCNTs effectiveness towards weakening the toxicity of pristine MWCNTs also caution for extrapolating in vitro data to in vivo observations. The observations further lend credibility for exploiting the zebra fish as a model system for analyzing the effects of MWCNTs functionalization.

Novel pilot scale photocatalytic treatment of textile & dyeing industry wastewater to achieve process water quality and enabling zero liquid discharge

This paper presents a novel end-to-end pilot scale photocatalytic treatment of real textile & dyeing industry effluent, which involved innovative approach in primary treatment, followed by Heterogenous Photocatalysis (HP) involving nano-TiO2/UV as secondary treatment and suitable filtration leading to treated water meeting process water quality enhancing water re-use efficiency. This enables Zero Liquid Discharge (ZLD); which is the need of the hour in tackling problems of point source pollution and Water Conservation in developing countries like India. Overall treatment led to complete degradation and mineralization of organic pollutants and dye stuff thereby achieving adequate treatment, complete decolourization and deodorization of the effluent and almost hundred times less quantities of sludge residues in comparison to those obtained in conventional treatment methods. The nature and elemental composition of sludge residues, as investigated using Energy Dispersive X-ray (EDX) elemental analysis, confirms complex organic dye components mineralized and nature being non-toxic. The complete treatment took place in 5 h without any kind of bioremediation method, which further highlights highly efficient and fast treatment coupled with small footprint. Overall cost of treatment is estimated to be around 1.55 USD/m3. Such an innovation in wastewater treatment is expected to bring a revolution in developing countries, which are grappled together with problems of rapid industrialization, urbanization, regulatory compliances and environmental challenges.

On the Selective Transport of Nutrients through Polymer Inclusion Membranes Based on Ionic Liquids

In the last few years, the use of ionic liquid-based membranes has gained importance in a wide variety of separation processes due to the unique properties of ionic liquids. The aim of this work is to analyze the transport of nutrients through polymer inclusion membranes based on different concentrations of methyltrioctylammonium chloride, in order to broaden the application range of these kinds of membranes. Calcium chloride (CaCl2) and sodium hydrogen phosphate (Na2HPO4) nutrients were used at the concentration of 1 g·L−1 in the feeding phase. The evolution of the concentration in the receiving phase over time (168 h) was monitored and the experimental data fitted to a diffusion-solution transport model. The results show very low permeation values for CaCl2. By contrast, in the case of Na2HPO4 the permeation values were higher and increase as the amount of ionic liquid in the membrane also increases. The surface of the membranes was characterized before and after being used in the separation process by scanning electron microscopy coupled to energy dispersive X-Ray spectroscopy (SEM–EDX) and elemental mapping analysis. The SEM–EDX images show that the polymer inclusion membranes studied are stable to aqueous solution contacting phases and therefore, they might be used for the selective transport of nutrients in separation processes.

Design guidelines for Al-12%Si latent heat storage encapsulations to optimize performance and mitigate degradation

We provide detailed insight into the growth kinetics of intermetallic layers formed at the interface of molten Al-12%Si with cylindrical encapsulations of 316L stainless steel. This knowledge is relevant for the design and operation of high-temperature latent heat storage and energy harvesting devices at application-relevant conditions. Our continuous experiments on iron-aluminide deposition rates at 600 °C and 700 °C lasted up to 120 days. The layer thickness was determined in metallographic cross sections by light microscopy. We observed deviations from standard growth models, including a delayed layer growth onset at 600 °C and strongly non-parabolic kinetics at 700 °C. We developed a numerical diffusion model that accommodated temperature dependent kinetics and explained the observed deviations by incorporating de-passivation and dissolution phenomena. Numerical fitting of the model to the experiments provided optimized mobility parameters that agree with those reported for the Fe2Al5 compound, whose presence was confirmed by energy dispersive X-ray elemental analysis. Differential scanning calorimetry revealed reductions in heat of fusion and melting temperature, of −10% and −10 K, respectively, after 120 days at 700 °C. Fe concentration in the melt increased from <0.3% to 2.6%, under the same conditions. The validated model was then used to provide design guidance for heat storage applications including degradation. For 8760 h of full-load-charging: a energy density of 370 kJ/kg was conserved, with variable source temperature distribution. For high power density configurations (1430 kW/m3) narrow source temperature distributions were beneficial. Our multi-month experimental campaigns enable more accurate degradation and performance predictions and provide guidelines that result in better long-term performance of the Al-12%Si phase change media.

Fabrication and characterization of a titanium dioxide (TiO2) nanoparticles reinforced bio-nanocomposite containing Miswak (Salvadora persica L.) extract - the antimicrobial, thermo-physical and barrier properties.

Objective: The microbial, physico-chemical and optical corruptions threaten a variety of foods and drugs and consequently the human biological safety and its accessible resources. The humanbeing’s tendency towards bio-based materials and natural plant-extracts led to an increase in the usage of antimicrobial biocomposites based on medicinal herbs. Miswak (Salvadora persica L.) extract (SPE) has been proved effective for its antimicrobial and other biological activities. Therefore, in this study, titanium dioxide (TiO2) nanoparticles (TONP) and SPE were applied to fabricate antimicrobial carboxymethyl cellulose (Na-CMC) based bio-nanocomposites which would simultaneously promote some thermo-physical and barrier properties.Methods: CMC-neat film (C1), CMC/TONP-2% (C2) and CMC/TONP-2% with 150, 300 and 450 mg/mL SPE (SPE150, SPE30 and SPE450, respectively) were fabricated. The physical and mechanical properties; elemental mapping analysis (MAP), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA-DTG); fourier transform infrared (FTIR), energy-dispersive X-ray (EDX) and UV-vis spectroscopies were done to further validate the results.Results: Addition of TONP (2%) improved the blocking of UV light at 280 nm while SPE-containing nanocomposites completely blocked it. FTIR, XRD and SEM confirmed the formation of homogeneous films and high miscibility of applied materials. TONP led to an increase in Young’s modulus (YM) and stress at break (SB) while SPE decreased them and enhanced the elongation to break (EB) (flexibility) of the active nanocomposites. Compared to CMC-film, the thermo-gravimetric analysis (TGA-DTG) showed a higher thermal stability for CMC/TONP and CMC/TONP/SPE nanocomposites. The EDX spectroscopy and elemental mapping analysis (MAP) proved the existence and well-distributedness of Na, K, Cl, S, Ti, F and N elements in SPE-activated nanocomposites. The pure SPE and SPE-activated nanocomposites showed a favorable antimicrobial activity against both gram-positive (Staphylococcus aureus) and negative (Escherichia coli) bacteria.Conclusion: The CMC-TiO2-SPE nanocomposites were homogeneously produced. Combination of TiO2 nanoparticles and dose-dependent SPE led to an improvement of thermal stability, and high potential in antimicrobial and UV-barrier properties. These results can generally highlight the role of the fabricated antimicrobial bio-nanocomposites as a based for different applications especially in food/drug packaging or coating.

High-Resolution SEM and EDX Characterization of Deposits Formed by CH₄+Ar DBD Plasma Processing in a Packed Bed Reactor.

The deposits formed during the DBD plasma conversion of CH4 were characterized by high-resolution scanning electron microscopy (HRSEM) and energy dispersive X-ray elemental analysis (EDX) for both cases of a non-packed reactor and a packed reactor. For the non-packed plasma reactor, a layer of deposits was formed on the dielectric surface. HRSEM images in combination with EDX and CHN elemental analysis of this layer revealed that the deposits are made of a polymer-like layer with a high content of hydrogen (60 at%), possessing an amorphous structure. For the packed reactor, γ-alumina, Pd/γ-alumina, BaTiO3, silica-SBA-15, MgO/Al2O3, and α-alumina were used as the packing materials inside the DBD discharges. Carbon-rich agglomerates were formed on the γ-alumina after exposure to plasma. The EDX mapping furthermore indicated the carbon-rich areas in the structure. In contrast, the formation of agglomerates was not observed for Pd-loaded γ-alumina. This was ascribed to the presence of Pd, which enhances the hydrogenation of deposit precursors, and leads to a significantly lower amount of deposits. It was further found that the structure of all other plasma-processed materials, including MgO/Al2O3, silica-SBA-15, BaTiO3, and α-alumina, undergoes morphological changes. These alterations appeared in the forms of the generation of new pores (voids) in the structure, as well as the moderation of the surface roughness towards a smoother surface after the plasma treatment.

Petrographic and geochemical characterization of coal from Santa Susana Basin, Portugal

The current and future importance of coal as a geological resource is related with the production of coke, carbon materials, carbon derivatives and other chemical products as well as a promising alternative source of critical trace elements. This study aims the comprehensive characterization of coals from the Santa Susana Basin (SSB), SW of Portugal. The SSB is a Pennsylvanian continental basin located along the Santa Susana Shear Zone that separates two tectonostratigraphic zones of Iberian Massif. Samples of coal and coaly silt-claystone from the main outcrops, Jongeis and Vale de Figueira, were collected for this study. The methodologies used for the petrographic and geochemical characterization included: optical microscopy, scanning electron microscopy with energy dispersive X-ray spectrometry, proximate and elemental analysis and inductively coupled plasma mass spectrometry (ICP-MS). The results demonstrate that the organic matter of coal from SSB is essentially composed of vitrinite and small amounts of inertinite. The mineral matter includes detrital minerals (mainly quartz and clay minerals), iron oxides and oxidized and non-oxidized framboidal pyrite. Epigenetic carbonates (dolomite and ankerite) were only observed in samples from Jongeis outcrop. Vitrinite random reflectance of the samples ranges between 0.90% and 1.25%, indicating a bituminous coal rank. The slightly higher vitrinite reflectance and the occurrence of epigenetic carbonates in samples from Jongeis can be related with differentiated burial history of the basin and post-depositional processes including fluids circulation that may have promoted the enhancement of the thermal maturity. When compared with the geochemical composition of worldwide hard coals, samples from Vale de Figueira are significantly enriched in Cs and In, while samples from Jongeis are significantly enriched in In and Mn. Considering the elements' mode of occurrence, the majority of elements are preferentially associated with mineral matter. The elements S, Cd, Mo, Pb and Se have organic affinity. The strong positive correlation between Ca and Mg, Mn and Te indicates their association with carbonate phases, which is in accordance with the carbonate composition.

Computer-Aided Facial Reconstruction of "Mary-Magdalene" Relics Following Hair and Skull Analyses.

The supposed relics of “Mary-Magdalene” are preserved in Provence (France) in an ancient tradition. They consist of a dry skull and a lock of hair. For the first time, they were officially subjected to an extensive medico-surgical examination by photogrammetry, high-magnification binocular lenses, scanning electron microscope, and energy-dispersive X-ray elemental analysis, to propose a full computer-aided facial reconstruction. The preliminary results are presented here.