EDX Elemental Analysis Research Articles

Amino-functionalization of PVA/TiO2-CeO2 nanohybrid adsorbent for the removal of selenium ions from aqueous solutions: Equilibrium and kinetics studies

ABSTRACT In this study, a hybrid nanoadsorbent (HnA), (PVA/TiO2-CeO2), was synthesized and amino-functionalized by 3-aminopropyltriethoxysilane (APTES) to produce AHnA, for use in an advanced selenium adsorption study focusing on nonlinear equilibrium and kinetics models. AHnA was characterized using XRD, FTIR spectroscopy, SEM, and EDX elemental analyses, as well as BET-BJH techniques. According to the FTIR results, APTES has successfully cross-linked the PVA chain and introduced amine groups on the surface. Moreover, the modification resulted in an increase in the total pore volume from 0.0061 cm3/g in HnA to 0.021 cm3/g in AHnA. Several adsorption experiments were conducted to determine the impact of varying contact times within a pH range of 1 to 8 and concentrations ranging from 5 to 200 mg/L, using a One-Variable-At-a-Time (OVAT) procedure. Accordingly, a dosage of 2 g/L of modified nanocomposite exhibits optimal performance for removing selenium from a 20 mg/L solution at an acidic pH of 3 during 300 minutes of contact with selenium ions, while conforming to a pseudo-second-order kinetic model. The assessment of various nonlinear isotherm models for analyzing equilibrium data revealed that the experimental data of selenium adsorption conformed to a generalized isotherm, showing a maximum monolayer adsorption capacity of 17.643 mg/g.

Enhancing electrochemical properties of bacterial cellulose-derived carbon nanofibers through physical CO2 activation

Carbon nanofiber (CNF) derived from carbonization of bacterial cellulose (BC), with a unique three-dimensional porous nanostructure, has received significant interest in electrochemical applications. In this study, CNF samples were physically activated in CO2 at different temperatures and durations. Raman spectroscopy and FTIR analysis showed that CO2 activation caused hexagonal lattice defects, disorder, and oxygen-related functional groups in an amorphous carbon structure. CNF surface morphology changed after physical activation, reducing fiber diameter to 55 nm and introducing mesopores. Through activation temperature and time adjustments, surface area (870.1 m2/g) and micropore surface area (535.6 m2/g) and pore volume (0.2148 cm3/g) increased. EDX elemental analysis showed that activated CNF had a carbon concentration of > 90 %, while XPS analysis showed surface functional groups like C-C (sp2) and C-C (sp3) hybridization, which could improve electrolyte ion adsorption and accessibility. Electrochemical properties improved owing to CO2 activation. The optimal activation condition of 800 ℃ for 60 min resulted in the highest specific area capacitance of 552 mF cm−2 at 1 mA cm−2. This activated CNF electrode retained capacitance nearly unchanged up to 3,000 cycles. It also achieved the highest energy density of 76.7 mWh cm−2 at 500 mW cm−2. This study demonstrates the efficacy of CO2 physical activation for enhancing the electrochemical properties of CNF electrodes. The findings also highlight the importance of tailoring activation conditions, providing valuable insights for the design of advanced energy storage materials.

Full colour luminescence tuning including white light from a mixed lanthanide activated metal-organic complex

In an attempt, metal–organic compounds of rare earth ions with 2,6-pyridinedicarboxylic acid (H2pydc) were synthesized and characterized. This paper summarizes the synthesis, characterization, and multicolour luminescence behaviour of a europium and terbium co-doped metal–organic compound (MOC) of formula [Y1.972Eu0.013Tb0.014(pydcH)6]·3H2O, 1 {H2pydc = 2,6-pyridinedicarboxylic acid}. The synthesis was performed by simple solvent evaporation method. We have also synthesized a pure yttrium based compound [Y2(pydcH)6]·3H2O, 1a following a similar procedure. The powder XRD patterns indicated that 1 and 1a were new materials; the patterns being entirely consistent with the simulated XRD pattern generated based on the structure of pure Eu compound determined using the single-crystal XRD. Compound 1 was well characterized by SEM, IR, TGA, EDX, and EDX elemental mapping analysis. Compound 1 showed different colour upon the variation of the excitation wavelength from 260 nm to 385 nm.

Conditioning Influence of Kaolinite Matrices on Flexural Strength of Raw Pressed Slurry Collected from Ceramic Tile Production Wastewater

Kaolinite is able to assure the high binding affinity of the filler particles of raw ceramic bodies. It acts as a matrix that strongly holds the other constituents’ particles in a compact structure. The slurry samples were characterized by XRD, mineralogical microscopy and SEM coupled with an EDX elemental analysis. The slurry collected from the ceramic tile production wastewaters had a significant amount of kaolinite (36%), mostly fine particles of 3 µm, less surrounding quartz (37%) and mullite (19%) particles of 5–100 µm in diameter and traces of lepidocrocite (8%). It is a dense paste with a relative moisture of 25%. The square bar of the slurry as received, pressed at a load of 350 N, had a flexural strength of 0.61 MPa. Increasing the moisture to 33% using regular water, followed by mechanical attrition at 2000 rpm for 5 min, resulted in a porous bar with a flexural strength of 0.09 MPa; by increasing the attrition speed to 6000 rpm, the microstructural homogenization was improved and the flexural strength was about 0.68 MPa. It seems that regular water does not assure an optimal moisture for the kaolinite matrix conditioning. Therefore, we used technological water at pH = 10, a moisture of 33% and attrition at 6000 rpm for 5 min, and the bar pressed at a load of 350 N had a flexural strength of 1.17 MPa. The results demonstrate that the bar moistened with technological water and an attrition regime assured a proper conditioning for the kaolinite matrix, achieving the optimal binding of the quartz and mullite particles under the pressing load. Bars with the optimal mixture were pressed at several loads, including 70, 140, 210 and 350 N, and the flexural strength was progressively increased from 0.56 MPa to 1.17 MPa. SEM fractography coupled with atomic force microscopy (AFM) revealed that the optimal moisture facilitated a proper kaolinite particle disposal regarding the quartz and mullite filler particles, and the progressive load assured the strong binding of the finest kaolinite platelets onto their surface.

Insights into the hexamine-assisted ZnO based-MOFs formation on PET fabric for improved self-cleaning, flame retardant, and hydrophilic properties

Organo-metallic frameworks (MOFs) have attracted much attention in the last decade due to their large pore size, large surface area, selective adsorption of small molecules, and optical or magnetic responses in the presence of guest molecules. Particularly, the use of MOFs on textile products through in situ synthesis leads to special properties in a simple method. Here, the polyester fabric was first activated by alkali hydrolysis and then the ZnO-based MOFs were synthesized to obtain a fabric with multifunctional features. FESEM images and EDX elemental analysis showed the presence of MOF particles and zinc, nitrogen, and hydrogen on the polyester surface. The weight of the treated samples increased however the water spreading time decreased due to the polar groups of the MOFs creating higher hydrophilic properties. The presence of hydroxyl and amine groups on the surface of the MOFs-treated polyester was confirmed by FTIR spectroscopy. The final fabric showed photocatalytic self-cleaning, and UV protection properties. In addition, TGA, ash percentage, and burnt length results demonstrated the flame-retardant properties. The tensile strength, thickness, and stiffness of the MOFs-treated fabrics also increased. Finally, the hexamine-assisted ZnO-based MOFs on the polyester surface improve its properties and usability.

Hybrid Siloxane Materials Based on a Mutually Reactive Epoxy–Amine System: Synthesis, Structure, and Thermal Stability Investigations

Hybrid siloxane materials based on a mutually reactive epoxy–amine system are organic-inorganic hybrid materials synthesized via the sol–gel reaction of siloxane precursors, followed by the polymerization of organo-functionalized oligosiloxanes. Therefore, using a new hybrid system as the reaction product resulting from the reaction between 1,3-bis(3-glycidoxypropyl)-l, 1,3,3-tetramethyldisiloxane—C16H34O5Si2—(gp-DS) and p-phenylenediamine—C6H4(NH2)2—(PPD), an aromatic diamine, was obtained. The chemical structure of the synthesized hybrid siloxane material was confirmed via Fourier Transform Infra-Red (FTIR) spectroscopy, mass spectrometry (MS), and 1H-NMR spectroscopy. The morphology and surface chemical composition was highlighted via scanning electron microscopy (SEM) equipped with an EDX elemental analysis system. Further, the thermal stabilities of the prepared hybrid siloxane and its precursors have been investigated via thermogravimetric analysis (TGA), proving the modification of epoxy-functional disiloxanes with a paraphenylenediamine reagent that made it possible to produce hybrid siloxane materials with very good thermal stabilities and dual weak hydrophilic/hydrophobic surfaces.

Influence of Pr-ion substitution in Cu2X hexaferrites on their magnetic and dielectric properties

A series of Sr2Cu2PrxFe28-xO46 (x = 0.00 to x = 0.32 with a step of 0.08) hexagonal ferrite was synthesized by the heat treatment method, and heated at 1300 °C for 6 h. These samples were characterized using FTIR, XRD, FESEM, VSM, and low-frequency (20 Hz–2 MHz) dielectric measurements. FTIR investigation confirms the ferrite phase formation in all the samples. XRD investigation reveals that all samples possess the X-type as a major phase with a minor M-phase. FESEM images show smaller grain size ranges between 25.27 μm and 51.25 μm. EDX elemental analysis confirms the existence of constituent elements in synthesized materials. VSM analysis shows that prepared ferrites possess a soft magnetic nature, the saturation magnetization of heated samples was found in the range of 35.99 Am2/kg to 49.44 Am2/kg, and coercivity was observed in the range of 10.372 kA/m to 37.443 kA/m. Relaxation peaks have been observed in the loss tangent profile for x = 0.00, 0.08. The Nyquist plot for samples S1 and S2 represents the low-loss universal capacitance circuit, while samples S3 to S5 represent the parallel conductance-capacitance circuit.

Pecten oculi of kestrel (Falco tinnunculus rupicolaeformes) and little owl (Athene noctua glaux): Scanning electron microscopy and histology with unique insights into SEM-EDX elemental analysis.

There is scanty data about the comparative morphological features between the pecten oculi of two carnivorous birds with different visual active clock hours: the diurnal common kestrel and the nocturnal little owl. This study illustrated the comparative gross, scanning electron microscopy, and histological characteristics between pecten oculi of kestrel and little owl. This study first attempts to describe the scanning electron microscopy-energy dispersive x-ray (SEM-EDX) elemental analysis at the parts (apex, middle, and base) of the pecten oculi of these two birds. The present study results observed the same position, origin, directions, parts, convoluted outer pleat surfaces, and SEM-EDX elemental analysis, but there were some minor variations due to the different visual active clock hours. These minor variations were summarized in the following points: pleat number (21-23 in the kestrel and 10-11 in the owl), shape (fan rhomboid in the kestrel and accordion in the owl), inter-pleat spaces (wider in the kestrel than in the owl), pigmentations (highly black pigmented in the owl than in the kestrel), hyalocyte cell aggregations (highest in the middle and dwindling at the apex and base in the kestrel, while highest in the middle and base and dwindling at the apex in the owl), and SEM-EDX elemental analysis percentage. SEM/EDX elemental analysis confirmed the presence of oxygen (the highest one), carbon, nitrogen (the second one), nitrogen (the third one), and aluminum (the lowest one) in varying percentages within the pecten oculi; these findings contribute to our understanding of its structural, adaptations with different visual active clock hours, and functional characteristics. RESEARCH HIGHLIGHTS: This study compared the pecten oculi of two carnivorous birds with different visual active clock hours: the diurnal common kestrel and the nocturnal little owl. Anatomically, the characteristic features were similar in both the birds, but some minor variations were observed adapted to their visual active clock hours. The pecten oculi of both birds were analyzed using SEM-EDX for elemental analysis, and it revealed that oxygen was the highest elemental concentration, followed by carbon and nitrogen. Aluminum concentrations were small as per SEM-EDX analysis. The study suggested that the pecten oculi of these birds are related to their active visual clocks and adaptive nutritional mechanisms.

Green creation of CoFe2O4 nanosorbent for superior toxic Cd ions elimination

Abstract A mesoporous cobalt ferrite nanostructure was prepared by a green chemistry approach using Pimpinella anisum extract for Cd (II) ions elimination from an aqueous medium. The metal ions adsorption was explored under varying operating conditions, comprising of the pH, initial adsorbate concentration, and contact time. The synthesized sorbent was characterized by various techniques where the XRD data verified a ferrite structure of ≈25 nm crystallite size and the EDX elemental analysis affirmed the presence of the corresponding elements. The CoFe2O4 established porosity characteristic of 10.8 m2 g−1 BET-specific surface area and 0.023 cm3 g−1 pore volume values. Batch mode experiments ascertained that the Cd (II) ions uptake was pH-dependent, with peak removal of 170 mg/g accomplished at pH = 5. The adsorption process of the metal ions onto the mesoporous nanomaterial surface fitted well with the Langmuir isotherm and pseudo-second-order kinetics models. The mechanistic aspects indicated the role of intra-particle and film diffusion in the adsorption process. The adsorbent could efficiently remove the pollutant up 74.3 % to four cycles of successful regeneration. This investigation endorsed that CoFe2O4 might be potent candidate for heavy metals from aqueous systems.

Exploring the Catalytic Efficiency of Copper-Doped Magnetic Carbon Aerogel for the Coupling Reaction of Isatin Oxime with Phenylboronic Acid Derivatives

AbstractA highly efficient catalyst, Cu-doped poly(N-[3-(dimethylamino)propyl]methacrylamide, acrylic acid, N-vinyl imidazole) (PDAI) magnetic carbon aerogel (CPIMCA), was successfully employed for the synthesis of isatin nitrone derivatives. The 3D porous CPIMCA catalyst demonstrated outstanding performance through the application of a coupling reaction between isatin oxime and phenylboronic acid derivatives, providing up to 98% yield of the required nitrone derivatives. Remarkably, the incorporation of copper within the polymeric structure of the magnetic carbon aerogel exhibited a significant influence on catalytic activity, even at a low overall copper content of approximately 2%. This was confirmed through EDX elemental mapping analysis, further establishing the competence of the catalyst for catalytic reactions. Comparative studies revealed that CPIMCA outperformed Cu(Oac)2 catalyst, providing a notable 10–15% increase in product yield. This superior performance can be attributed to the unique synergistic effect of copper, iron, and carbon aerogel as the polymeric matrix, highlighting the exceptional capabilities of CPIMCA as a catalyst.

Exploring Wild Edible Plants in Malakand, Pakistan: Ethnobotanical and Nutritional Insights

Human beings have used wild edible plants (WEPs) for food since ancient times. The poor and underprivileged people of the district of Malakand, Pakistan, also depend on wild edible plants (WEPs) to fulfill their food and nutrition needs. Wild edible plants (WEPs) are a potential solution for overcoming food shortages for families living in rural areas. The current study evaluated the ethnobotanical, nutritional, and elemental potential of some wild edible plants (WEPs) commonly used by local people in the district of Malakand, Pakistan. Ethnobotanical information was collected from local people through a semi-structured questionnaire. The ethnobotanical information collected about wild edible plants revealed that two wild edible species belong to the family Fabaceae, two plant species belong to the family Polygonaceae, and one plant species belongs to each family Amaranthaceae, Brassicaceae, Chenopodiaceae, Malvaceae, Oxalidaceae, and Portulaceae. The plants collected were all herbs, and the parts used as edible parts were mostly leaves and young shoots. All the collected plants were predominantly used as vegetables by local people. The proximate nutritional analysis was carried out according to the official methods of AOAC (from 2016). The proximate nutritional analysis revealed that the selected WEPs are a good source of important nutrients like carbohydrates, proteins, fibers, fats, and caloric energy. The proximate nutritional analysis of selected WEPs revealed that the highest (%) moisture content was calculated in Nasturtium officinale W.T. Aiton (90.45 ± 0.3); the highest dry matter (%) was present in Oxalis corniculata L. (21.60 ± 0.2); the highest ash (%) in Chenopodium album L. (17.80 ± 0.3); the highest crude fibers (%) in Meliolotus indicus (L.) All (16.45 ± 0.5); the highest crude protein (%) in Meliolotus indicus (L.) All (14.40 ± 0.1%); the highest crude fats (%) in Rumex hastatus Don. (3.80 ± 0.04); the highest percentage of carbohydrates in Portulaca oleracea L. (65.38 ± 0.6); and the maximum energy value was calculated for Portulaca oleracea L. (321.38 ± 0.4 Kcal/100 g). The elemental analysis of wild edible plants (WEPs) was carried out through energy-dispersive X-ray analysis (EDX). The EDX analysis showed that these WEPs consist of crucial and imperative elements such as C, O, N, P, Mg, K, S, Ca, Al, Si, Cl, Fe, Cu, Na, and Zn, which are integral parts of the human diet. Following the results of the EDX elemental analysis, Portulaca oleracea accounted for the highest concentration (%) of carbon, Oxalis corniculata accounted for the highest concentration (%) of oxygen, and Nasturtium officinale accounted for the maximum concentration of nitrogen (9.70%). The current study revealed that the research area is rich in diversity of wild edible plants (WEPs), a cheap and economical food source for locals. The study also showed that these wild edible plants (WEPs) possess all the crucial nutrients and elements imperative for human food and health. These wild edible plants (WEPs) will play a key role in a sustainable food system in the future.

Heterogenous electro-Fenton degradation of sulfamethoxazole on a polyethylene glycol-coated magnetite nanoparticles catalyst

We report the preparation and application of poly (ethylene) glycol (PEG) coated magnetite nanoparticles (MNPs) catalyst for the heterogeneous electro-Fenton (HEF) degradation of sulfamethoxazole in real wastewater PEG-coated MNPs of four MNP:PEG ratios were synthesised using the co-precipitation method. The synthesised MNP were characterised using FTIR, XRD, EDX, TEM, and CHN elemental analysis. It was observed that the coating of MNP with PEG influences the nanoparticle size, agglomeration tendencies and catalytic efficiency of MNPs properties in the HEF degradation process. A 1:1 optimal MNP:PEG catalyst yielded 91% sulfamethoxazole degradation and 48% total organic carbon removal in 60 min, which is an improvement of 11% over degradation with the uncoated MNP. The PEG-coated MNP showed higher stability in 10 consecutive reaction cycles, reduced leaching, and improved performance at a lower dosage and broader pH range than the uncoated MNPs. These results show that coating MNP with PEG enhances HEF catalytic performance in the degradation of sulfamethoxazole in wastewater.

Highly Active Nickel (II) Oxide-Supported Cerium Oxide Catalysts for Valorization of Glycerol into Oxygenated Fuel Additives.

Acetylation of glycerol to yield monoacetin (MAT), diacetin (DAT), and triacetin (TAT) over NiO-supported CeO2 (xNiO/CeO2) catalysts is reported. The catalysts were synthesized utilizing a sol-gel technique, whereby different quantities of NiO (x = 9, 27, and 45 wt%) were supported onto the CeO2 substrate, and hexadecyltrimethylammonium bromide (CTABr) served as a porogen. The utilization of EDX elemental mapping analysis confirmed the existence of evenly distributed Ni2+ ion and octahedral NiO nanoparticles on the CeO2 surface through the DRS UV-Vis spectroscopy. The most active catalyst is 27NiO/CeO2 based on TAT selectivity in the glycerol acetylation with ethanoic acid, attaining 97.6% glycerol conversion with 70.5% selectivity to TAT at 170 °C with a 1:10 glycerol/ethanoic acid molar ratio for 30 min using a non-microwave instant heating reactor. The 27NiO/CeO2 is reusable without significant decline in catalytic performance after ten consecutive reaction cycles, indicating high structure stability with accessible active acidity.

Intramedullary bone tissue reaction of ion-releasing resin-modified glass-ionomer restoration versus two calcium silicate-based cements: an animal study

This comparative study was conducted to assess the intramedullary bone tissue reaction of an ion-releasing resin modified glass-ionomer cement with claimed bioactivity (ACTIVA bioactive resin) restorative material versus Mineral Trioxide Aggregate High Plasticity (MTA HP) and bioceramic putty iRoot BP Plus. Fifty-six adult male Wistar rats were assigned into 4 equal groups (14 rats each). A surgical intramedullary bi-lateral tibial bone defects were performed in rats of the control group I (GI) and left without any treatment to be considered as controls (n = 28). The rats of groups II, III and IV were handled as group I except that the tibial bone defects were filled with ACTIVA, MTA HP and iRoot BP, respectively. In all groups, rats were euthanized after one month and specimens were processed to histological investigation, SEM examination and EDX elemental analysis. In addition, semi-quantitative histomorphometric scoring system was conducted for the following parameters; new bone formation, inflammatory response, angiogenesis, granulation tissue, osteoblasts and osteoclasts. The clinical follow-up outcome of this study revealed the recovery of rats after 4 days post-surgical procedure. It was observed that the animal subjects returned to their routine activities, e.g., walking, grooming and eating. The rats showed normal chewing efficiency without any weight loss or postoperative complications. Histologically, the control group sections showed scanty, very thin, new bone trabeculae of immature woven type located mostly at the peripheral part of the tibial bone defects. These defects exhibited greater amount of thick bands of typically organized granulation tissue with central and peripheral orientation. Meanwhile, bone defects of ACTIVA group showed an empty space surrounded by thick, newly formed, immature woven bone trabeculae. Moreover, bone defects of MTA HP group were partially filled with thick newly formed woven bone trabeculae with wide marrow spaces presented centrally and at the periphery with little amount of mature granulation tissue at the central part. The iRoot BP Plus group section exhibited an observable woven bone formation of normal trabecular structures with narrow marrow spaces presented centrally and at the periphery showed lesser amount of well-organized/mature granulation tissue formation. Kruskal Wallis test revealed total significant differences between the control, ACTIVA, MTAHP and iRoot BP Plus groups (p < 0.05). Meanwhile, Mann–Whitney U test showed significant difference between control and ACTIVA groups, Control and MTA HP groups, control and iRoot BP Plus groups. ACTIVA and MTA HP groups, ACTIVA and iRoot BP Plus (p ˂ 0.05) with no significant difference between MTA HP and iRoot BP Plus (p > 0.05). The elemental analysis outcome showed that the lesions of the control group specimens were filled with recently created trabecular bone with limited marrow spaces. EDX tests (Ca and P analysis) indicated a lower degree of mineralization. Lower amounts of Ca and P was expressed in the mapping analysis compared with other test groups. Calcium silicate-based cements induce more bone formation when compared to an ion-releasing resin modified glass-ionomer restoration with claimed bioactivity. Moreover, the bio-inductive properties of the three tested materials are likely the same. Clinical significance: bioactive resin composite can be used as a retrograde filling.

Experimental and Modeling Optimization of Strontium Adsorption on Microbial Nanocellulose, Eco-friendly Approach

Green synthesized cellulose nanocrystals (CNCs) was prepared using Neurospora intermedia, characterized, and used to remove Strontium ions (Sr2+) from an aqueous solution with high efficiency. The characterization of CNCs was performed using a UV-Vis Spectrophotometer, Dynamic Light Scattering (DLS), Zeta Potential (ZP), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) mapping, EDX elemental analysis and BET surface analyzer. In this study, Response Surface Methodology (RSM) based on Box-Behnken Design (BBD) was successfully applied for the first time to optimize the dynamic adsorption conditions for the maximum removal of Sr2+ ions from aqueous solutions using CNCs as adsorbent. The effects of parameters, such as initial concentration of Sr2+ (50–500 ppm), adsorbent dosage (0.05–0.2 g/50ml), and contact time (15–120 min.) on removal efficiency were investigated. A mathematical model was studied to predict the removal performance. The significance and adequacy of the model were surveyed using the analysis of variance (ANOVA). The results showed that the second-order polynomial model is suitable for the prediction removal of Sr2+ with regression coefficient (R2 = 97.41%). The highest sorption capacity value of Sr2+ was obtained (281.89 mg/g) at the adsorbent dosage of 0.05 g/50 ml, contact time of 120 min., and the pollutant (Sr2+) concentration of 275 ppm.

Surface-Modified TiO2@SiO2 Nanocomposites for Enhanced Dispersibility and Optical Performance to Apply in the Printing Process as a Pigment.

The grafted modification TiO2@SiO2 composite was fabricated by a liquid-phase deposition method with Na2SiO3 and a grafting reaction with a silane coupling agent. First, the TiO2@SiO2 composite was prepared, and the effect of deposition rate and silica content on the morphology, particle size, dispersibility, and pigmentary property of TiO2@SiO2 composites was investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and ζ-potential. The islandlike TiO2@SiO2 composite had a good particle size and printing performance compared with the dense TiO2@SiO2 composite. The presence of Si was confirmed by EDX elemental analysis and XPS, and a peak at 980 cm-1 belonging to Si-O was observed in the FTIR spectrum, confirming the presence of SiO2 anchored at TiO2 surfaces via Si-O-Ti bonds. Then, the islandlike TiO2@SiO2 composite was modified by grafting with a silane coupling agent. The effect of the silane coupling agent on the hydrophobicity and dispersibility was investigated. The peaks at 2919 and 2846 cm-1 belong to CH2 in the FTIR spectrum, and Si-C in the XPS confirmed the grafting of silane coupling agent to the TiO2@SiO2 composite. The grafted modification of the islandlike TiO2@SiO2 composite using 3-triethoxysilylpropylamine endowed it with weather durability, dispersibility, and good printing performance.

TOF-SIMS and AFM analysis of pH effect on the interfacial films on η-phase in aqueous salt solutions

The pH effect on the surface and interfacial films on η-phase (MgZn2) in aqueous solutions under acidic, neutral, and alkaline conditions has been evaluated using time of flight-secondary ion spectroscopy (TOF-SIMS), Atomic force microscopy (AFM) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX). TOF-SIMS depth profile plots reveal that under an acidic environment (pH2) deep corrosion penetration occurs with a dispersion of corrosion products which claims a considerable depth matrix cross-section. Under near neutral environments (pH 6), the corrosion film is seen to be stratified into two layers of different compositions, while in a slightly alkaline environment (pH 10) the film appears not to be distinctly differentiated, whereas in a very alkaline environment (pH 13) a compact film rich in hydroxides develops. TOF-SIMs surface and depth profile maps were consistent with the depth profile plots. SEM and AFM images reveal that the surface roughness increased in with a decrease in pH value from the acidic to the alkaline environments. EDX elemental composition analysis also indicated a severe drop in the zinc content of the film in the alkaline environment. Largely, metallic zinc enrichment occurs following the initial magnesium dissolution whose stability is greatly affected by the near-surface pH of the bulk solution, thus, giving rise to different film structures.

Development of doxorubicin-encapsulated magnetic liposome@PEG for treatment of breast cancer in BALB/c mice.

The magnetic doxorubicin-encapsulated liposome/PEG/Fe3O4 (called as DOX@m-Lip/PEG) was synthesized and studied as a novel nanocarrier for the treatment of breast cancer in BALB/c mice. Nanocarrier was characterized by FT-IR, zeta-potential sizer, EDX elemental analysis, EDX mapping, TEM, and DLS techniques. The results showed that the size of the nanocarrier was determined around 128nm by TEM. EDX study confirmed PEG-conjugation in the magnetic liposomes and was homogenously distributed in the nanosize range (100-200nm) with a negative surface charge (-61.7mV). The kinetic studies indicated that the release of doxorubicin from DOX@m-Lip/PEG follows the Korsmeyer-Peppas model. The n-value of the model was 0.315, indicating that doxorubicin release from the nanocarrier had a slow releasing rate and followed Fick's law. The DOX release from the nanocarrier lasted a long time (more than 300h). In in vivo part, a mouse 4T1 breast tumor model was used. The in vivo results indicated that DOX@m-Lip/PEG caused much stronger tumor cell necrosis and less cardiotoxic effects than the other groups. In conclusion, we show that m-Lip/PEG is a promising nanocarrier for low dosage and slow release of doxorubicin in treating breast cancer, and treatment with encapsulated DOX (DOX@m-Lip/PEG) demonstrated higher efficacy with low cardiac toxicity. Besides, the magnetic property of m-Lip@PEG nanocarrier allows it to be a potent mater for hyperthermia and MRI studies.

Cyclic Voltammetry of Screen-Printed Carbon Electrode Coated with Ag-ZnO Nanoparticles in Chitosan Matrix.

In this paper, the authors describe the fabrication of nanocomposite chitosan-based systems of zinc oxide (ZnO), silver (Ag) and Ag-ZnO. Recently, the development of coated screen-printed electrodes using metal and metal oxide nanoparticles (NPs) for the specific detection and monitoring of different cancer tumors has been obtaining important results. Ag, ZnO NPs and Ag-ZnO prepared by the hydrolysis of zinc acetate blended with a chitosan (CS) matrix were used for the surface modification of screen-printed carbon electrodes (SPCEs) in order to analyze the electrochemical behavior of the typical redox system of a 10 mM potassium ferrocyanide-0.1 M buffer solution (BS). The solutions of CS, ZnO/CS, Ag/CS and Ag-ZnO/CS were prepared in order to modify the carbon electrode surface, and were measured at different scan rates from 0.02 V/s to 0.7 V/s by cyclic voltammetry. The cyclic voltammetry (CV) was performed on a house-built potentiostat (HBP). The cyclic voltammetry of the measured electrodes showed the influence of varying the scan rate. The variation of the scan rate has an influence on the intensity of the anodic and cathodic peak. Both values of currents (anodic and cathodic currents) have higher values for 0.1 V/s (Ia = 22 μA and Ic = -25 μA) compared to the values for 0.06 V/s (Ia = 10 μA and Ic = -14 μA). The CS, ZnO/CS, Ag/CS and Ag-ZnO/CS solutions were characterized using a field emission scanning electron microscopy (FE-SEM) with EDX elemental analysis. The modified coated surfaces of screen-printed electrodes were analyzed using optical microscopy (OM). The present coated carbon electrodes showed a different waveform compared to the voltage applied to the working electrode, depending on the scan rate and chemical composition of the modified electrodes.

Structural, optical, and H2 gas sensing analyses of Cr doped CuO thin films grown by ultrasonic spray pyrolysis

Here, a specific metal oxide (CuO) and its impurity (Cr) added composites were grown onto glass substrates as nanostructured thin films by executing ultrasonic spray pyrolysis method. The effects of the varied Cr dopant concentration on the morphological, structural, optical and H2 gas sensor properties of the synthesized CuO thin films were determined by conducting scanning electron microscopy, X-ray Diffraction, X-ray photoelectron spectroscopy, photoluminescence spectroscopy, ultraviolet–visible spectroscopy, and gas detection analyses. The X-Ray Diffraction analysis revealed the presence of CuO crystals with predominant (111) plane and it changed to (002) orientation for the doped samples, where crystallite sizes varied between 32 and 46 nm. The structural studies disclosed that the crystalline structure modified due to the added impurities. The scanning electron microscopy observations unveiled polyhedron-like shape formations of the synthesized nanostructures which also showed clear indications of changed morphology due to the impacts of different Cr doping percentages. Besides, the presence of copper, oxygen, and chromium was confirmed by EDX elemental analysis as well as X-ray photoelectron spectroscopy. The optical examination concluded that absorbance values followed a random trend with respect to the increased impurity contents while bandgap decreased with the increase of doping concentration. And, it was also noted that the luminescent emission peaks decreased in the photoluminescence spectroscopy as a result of introduced impurity levels. Finally, H2 responsivity was detected for the grown films and found out that the impurity doping notably increased the sensitivity of the gas sensor based on the prepared CuO nanostructures.