Search

In this study, gold (Au), nanoclusters (NC) and heterogeneous titanium dioxide (TiO2) were successfully synthesized by low-temperature photoelectron spectroscopy. The chemical structure of Au-TiO2 was characterized by XRD, EDX, XPS and HR-TEM. Optical properties were evaluated using PL and UV–Vis, and electrical properties were evaluated using CV, CP, UPS and EIS parameters. The results showed that Au nanocluster (NCs) were converted into Au nanoparticles (NPs) during high sunlight, and the transfer mechanism was examined. In addition, the produced nanoparticles can form a Schottky barrier with TiO2, which affects the band structure. Moreover, the simultaneous synthesis of nanoparticles and nanoclusters adds an extra dimension to the understanding of the photoelectronic behavior of structured photoelectrodes. Moreover, this research shows that good control of the photography process can result in more photos. This improvement is related to several factors, including the plasmonic field and coupling line bending.

In this study, Co3O4 nanoparticles were used as nanocatalyst for two different series of nitrogen-containing heterocyclic compounds, including pyrrole (Pyo) derivatives and pyrano [2, 3-c]pyrazole (Pya[2, 3-c]Pyz) derivatives. In the synthesis of derivatives, using 15 mol% and 10 mol% of the catalyst for Pyo derivatives and Pya[2, 3-c]Pyz derivatives, respectively, an efficiency between 83% and 96%, were observed. In addition, novel derivatives of Pyo and Pya[2,3-c]Pyz were synthesized and their structures were confirmed. In general, the advantages of using cobalt nanoparticles compared to previous reports include the synthesis of new derivatives, lower temperature used in the synthesis of derivatives, shorter synthesis time and high efficiency. The biological properties of the synthesized products, such as antibacterial, antifungal, and antioxidant properties, were tested and investigated. In antibacterial and antifungal tests, IZD, MIC, MBC, and MFC were measured and reported. In antioxidant activity, IC50 was calculated and reported. High reusability, green and environmentally friendly, synthesis of new derivatives and synthesis of products with higher efficiency and shorter time were the important benefits of using cobalt nanoparticles as a catalyst. In antioxidant tests, the IC50 for synthesized Pyo derivatives and Pya[2, 3-c] Pyz derivatives were between 12.2 and 13.71 μg/mL, and 16.18–17.75 μg/mL, respectively. In antimicrobial testes, the MIC for synthesized Pyo derivatives and Pya[2, 3-c]Pyz derivatives were between 2 and 4,096 μg/mL, and 2–2048 μg/mL, respectively. The results showed that the antioxidant property of Pyo derivatives were more than Pya[2, 3-c] Pyz derivatives, but the antimicrobial effect of Pya[2,3-c] Pyz derivatives were more than Pyo derivatives. The antioxidant results proved that the activity of Pyo derivatives and Pya[2, 3-c] Pyz derivatives does not depend on the substitutions of the derivatives and is close to each other. Therefore, based on this, a proposed mechanism for stability of DPPH by Pyo derivatives and Pya[2, 3-c] Pyz derivatives were suggested. Finally, based on the more stable resonance structures of Pyo derivatives, compared to Pya[2, 3-c] Pyz derivatives, its high antioxidant property was justified. Pya[2, 3-c] Pyz derivatives has two heterocyclic rings connected together pyrano and pyrazole, but Pyo derivatives has only one heterocyclic ring (pyrrole). So high antimicrobial property of Pya[2, 3-c] Pyz derivatives compared to Pyo derivatives can be attributed to having two bioactive heterocyclic rings.

A synthetic superabsorbent polymer hydrogel nanocomposite was prepared by the free radical graft co-polymerization method. This study included the preparation of two surfaces: first sodium alginate-g-(acrylic acid-co-sodium; 4-ethenylbenzenesulfonate), SA-g-poly (Ac-co-EBS) hydrogel, and second surface hydrogel after zinc oxide loading SA-g-poly (Ac-co-EBS). Hydrogel nanocomposite was prepared from different monomers for the removal of pollutants. The physical characterizations of nanocomposite have been studied using several techniques like UV-vis, FTIR, FE-SEM, TEM, EDX, and XRD. The data from the adsorption study show that E% increases with increasing contact time, with the best agitation time of 1 h, after which the adsorption becomes constant. The increase in adsorbent amount 0.01–0.1 g, the percentage removal of tetracycline (TC) and phenol (PH) increased from 60.639–97.085 and 487.71–94.05%, respectively, and Qe decreased 606.39–97.08 to 487.1831–94.456 mg/g on hydrogel. The ∆H value is endothermic. All processes of adsorption are considered spontaneous, from a negative value of ∆G to a positive value of ∆S. The release of the TC drug was studied in conditions similar to those in the human body in terms of acidity and temperature. The cumulative release of TC drug in 3 h was 50.65%, 42.33%, pH = 7.5 and pH 1.2, respectively.

Abstract Introduction Biomarker testing is mandatory for the clinical management of patients with advanced non-small cell lung cancer (NSCLC). Myriads of technical platforms are now available for biomarker analysis with differences in terms of multiplexing capability, analytical sensitivity, and turnaround time (TAT). We evaluated the technical performance of the diagnostic workflows of 24 representative Italian institutions performing molecular tests on a series of artificial reference specimens built to mimic routine diagnostic samples. Methods Sample sets of eight slides from cell blocks of artificial reference specimens harboring exon 19 EGFR (epidermal growth factor receptor) p.E746_AT50del, exon 2 KRAS (Kirsten rat sarcoma viral oncogene homologue) p.G12C, ROS1 (c-ros oncogene 1)-unknown gene fusion, and MET (MET proto-oncogene, receptor tyrosine kinase) Δ exon 14 skipping were distributed to each participating institution. Two independent cell block specimens were validated by the University of Naples Federico II before shipment. Methodological and molecular data from reference specimens were annotated. Results Overall, a median DNA concentration of 3.3 ng/µL (range 0.1–10.0 ng/µL) and 13.4 ng/µL (range 2.0–45.8 ng/µL) were obtained with automated and manual technical procedures, respectively. RNA concentrations of 5.7 ng/µL (range 0.2–11.9 ng/µL) and 9.3 ng/µL (range 0.5–18.0 ng/µL) were also detected. KRAS exon 2 p.G12C, EGFR exon 19 p.E736_A750del hotspot mutations, and ROS1 aberrant transcripts were identified in all tested cases, whereas 15 out of 16 (93.7%) centers detected MET exon 14 skipping mutation. Conclusions Optimized technical workflows are crucial in the decision-making strategy of patients with NSCLC. Artificial reference specimens enable optimization of diagnostic workflows for predictive molecular analysis in routine clinical practice.

One-dimensional nanostructures are generally cited as nanowires, nanofibers, nanotubes, and so on. The foremost prominent feature of these materials is their electrical conductivity, which, unlike classical physics, doesn't increase their resistance because the diameter decreases. Numerous properties of these materials like electrical conductivity, optical, magnetic, biological, and environmental their sensory have created many applications for them altogether industries. nanowires (NWs) propose potential impact on electronics, computing, memory, data storage, communications, manufacturing, health, medicine, national security, and other economic sectors as well. NWs offer excellent surface-to-volume ratio (interface phenomena), low defect density, high optical output, and controllable n-type conductivity, making them more appropriate and sensitive for sensing applications. NWs with their ultra-sensitive and real-time detection capabilities lend their applications in nano biosensors, chemical sensors, gas sensors, and electrochemical sensors. NWs have been used in improving the optical absorption as well as for the collection efficacy in photovoltaic devices. NWs having small size, low weight, low cost for mass production, and are also compatible with commercial planar processes for large-scale circuitry. In the paper, the authors are focusing to summarize the recent advances in NWs with their potential applications in various fields such as research, health, security, education, entertainment, and power generation.

A key strategy for facilitating effective long-term photoinduced carrier separation and improving the photocatalytic efficiency of single photocatalysts is the development of heterojunction photocatalysts. The present study reports the fabrication of zinc stannate (ZnSnO3, ZSO) using an effortless and inexpensive sonochemical approach, and zinc stannate/graphitic carbon nitride (ZnSnO3/g-C3N4, ZSO/CN) nanocomposites with various contents of ZSO using a co-precipitation process assisted by ultrasound. Different instruments, including XRD, FTIR, FESEM, EDS, TEM, DRS, PL, BET, were used to characterize the purity, morphology, and structures of the products. The DRS data revealed that the introduction of CN reduced the bandgap of ZSO, which made it suitable for working in the visible region. The proficiency of ZSO, CN, and diverse ZSO/CN nanocomposites was perused for erythrosine (ER) and eriochrome black T (EBT) degradation. This is the first time ZSO/CN nanocomposites have been used to degrade organic dyes. The outcomes demonstrated that multiple elements impacted proficiency, for example, the amount of ZSO, quantity of catalyst, and concentration of dye. ZSO/CN nanocomposite containing 0.1 g ZSO showed the highest proficiency, in that 89.8 % of ER was degraded in the presence of 70 mg of ZSO/CN (0.1:1). The scavenger trials unveiled that superoxide radicals exhibited outstanding characteristics in the photoreactions. The kinetics survey manifested that a superior proficiency (89.8 %) donated the maximum rate constant (k = 0.0248 min−1).

In this Review, Phenolic resins have excellent dimensional, thermal, chemical and corrosion resistance. Also, the volatile substances produced during the thermal degradation of this resin have low toxicity and, in addition, they have high charring. Phenolic resins have been applied in many areas such as internal parts of war planes, structures used in marine platforms, flame retardant plastics and carbon/carbon composites due to having the mentioned favorable properties. In this article, phenolic resin samples of Resole reinforced with carbon fibers and graphene nanoparticles were prepared. In the last decade, the development of new polymer nanocomposites has grown significantly. In contrast to conventional and common composites, nanocomposites have a feature in which a filler that has a size of less than 100 nm in at least one dimension is used. One of the advantages of polymer nanocomposites is that it gives several properties to the primary polymer, despite the fact that it creates less limitations in its processability than other reinforcements. The key to these features is in the design and behavior of polymer nanocomposites, which includes the size and properties of the filler nanoparticle and the interface between the filler nanoparticle and the matrix. Nowadays, in many engineering applications, it is necessary to combine the properties of materials, and it is not possible to use one type of material that satisfies all the desired properties. For example, in the aerospace industry, there is a need for materials that have high strength, lightness, wear resistance and good resistance to ultraviolet light and do not lose their strength at high temperatures. Since it is difficult to find a material that has all the above properties, it is better to look for a method to combine the properties of the materials, this solution is the use of composite materials.

The density functionals M06–2X and B3LYP were exploited for investigating the impact of modifying the surface of a boron nitride nano-tube (BNNT) with the furan molecule in terms of energy, electronics, and geometry. According to the density functional theory (DFT) results, BNNT had a strong interaction with the furan molecule. So, the adhesion of the furan molecule onto the surface of BNNT was consistent with the chemical functionalization. Furthermore, the computed density of states indicated that the electronic features of the BNNT were adjusted with a partial chemical modification. Also, the functional energy raised by enhancing the electron donation property of the functional groups, which was due to the rise in the electrical conductance of BNNT in contrast with the pristine BNNT. Retaining the electronic features of BNNT and the increased solubility demonstrated that using furan to chemically modify BNNTs could be a useful method to purify them.

In this work, chitosan/graphene nanocomposite granules with weight percentages of 0.5%, 1%, 2% and 5% were prepared using a solution method. At first, graphene was oxidized with sulfuric and nitric acid then triethylenetetramine was grafted on graphene surface. Functionalized graphene was characterized by Fourier-transform infrared spectroscopy (FT-IR), Therapeutic Goods Administration (TGA), X-ray energy diffraction spectroscopy (EDX) and Scanning electron microscope (SEM). Results showed functionalization of graphene was successfully accomplished. The thermogravimetric analysis curves showed the pristine, oxidized and functionalized graphenes are stable up to 400, 250, and 300, respectively. The pristine graphenes are more stable than oxidized graphenes and the oxidized graphenes are more stable than functionalized graphenes. The observed stabilized temperature is known to be strongly influenced by the step of the functionalization. The morphology of nanocomposite was monitored by Scanning electron microscope (SEM). The SEM images showed that the porosity was reduced due to presence of nano graphenes. Results showed that the nanocomposite samples have higher potential for ion metals adsorption than that of neat chitosan. The adsorption of nano samples for cadmium was increased around 20% in comparison to neat chitosan. Atomic adsorption spectrometry showed that the optimal adsorption rate of cadmium ion occurs in a solution of 50 ppm with a pH = 7 and a contact time of 2 hours and an adsorbent of 25 mg.

Sol-gel chemistry is currently applied as one of the most widely used methods for synthesis of nanoparticles. In this method hydrolysis and poly-condensation reactions occur when the gel precursors are mixed with water and catalyst. The further condensation of sol particles into a three-dimensional network produces a gel. There are several parameters that effect on gelation time such as the molar ratio of alkoxide to water, the rate of hydrolysis, the type and amount of catalyst used, initial concentration of precursors and the temperature of hydrolysis and drying. Encapsulated solvent can be removed from a gel by either evaporative drying or supercritical drying. Where the resulting solids are known as a xerogel and an aerogel, respectively. During the drying process due to the surface tension of the liquid, a capillary pressure gradient is built in the pore walls, which is able to collapse most part of the pore volume. The volume shrinkage may be prevented by supercritical drying. The strength, thermal stability, pore structure and morphology of aerogels are keys to success for wider applications such as catalyst supports, thermal and acoustic insulators and adsorbents. Among catalyst support materials, alumina became popular recently due to its highly thermal and chemical stability and higher porosity. In the present study, synthesis of alumina gel as a support for nano-catalysts through hydrolysis of aluminum tri-sec-butoxide (ASB) in ethanol was investigated. The gel synthesis was carried out at 32 and 60 °C with different concentrations of water and precursor and different types and amounts of acid as catalyst. Rate of gel formation, efficiency of hydrolysis and polymerization and amount of gel production were measured and discussed. Results showed that acid addition around 0.2 ml and water to ASB malar ratio of 2 at 60 °C maximized the amount of gel produced and minimized the gelation time. Then, the alumina gel that synthesized at optimum conditions was dried by two different methods, at atmospheric pressure and temperature and at supercritical conditions of carbon dioxide and the results of Scanning Electron Microscopy were compared.