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•Recent Advances in Properties and Applications of Nanowires.•An overview of Method of making nanowires.•An overview of Types of nanowires.

In today’s world, wound healing is a growing serious problem for clinical institutes. In this study, nanofibrous scaffolds were prepared using polyurethane as a mat scaffold. Also, by immersing curcumin as an antibacterial component another scaffold was fabricated using the electrospinning technique. The obtained scaffolds were characterized by means of scanning electron microscopy, tensile analysis, porosity, and water vapor transmission rate. MTT and DAPI staining were used to prove the biocompatibility and cell attachment of the nanofibers. The curcumin incorporated into the PU scaffold can stop both the Gram-negative and Gram-positive bacteria activities through direct contact with them. Studies showed that the PU/Curcumin scaffold has considerable ability to play a key role in wound healing applications.

The present study was aimed to evaluate the moderating properties of lavender (Lavandula officinalis) essential oil (LEO) against immunotoxic effects of the organophosphate pesticide, malathion in rainbow trout, Oncorhynchus mykiss. For this purpose, fish were supplemented with LEO at dietary concentrations of 0.5, 1, 2 and 4 ml/kg diet LEO for 56 days. A non-LEO supplemented group was also considered as control. After 57 days feeding trial, biochemicals were assayed in the blood and kidney tissue and then fish exposed to a sub-lethal concentration of malathion [0.24 mg/l equal to 30% of LC50(0.8 mg/L)]. After 57 days feeding trial, the serum total immunoglobulin, respiratory burst activity, lysozyme activity and complement activity significantly elevated in fish treated with 1 and 2 ml LEO/kg diet compared to non-LEO supplemented individuals (P<0.01). Such changes were not observed in non-LEO supplemented fish (P>0.01). Significant elevations were observed in the expression of the immune genes (iNOS and C3genes) in fish treated with 0.2–2 mg LEO/kg diet compared to non-supplemented ones (P<0.01). The lysozyme and complement activity significantly decreased in fish fed 4 ml/kg diet (P<0.01). After exposure to malathion, all immune components significantly declined in control and those treated with 0.5, 1 and 4 ml LEO/kg diet (P<0.01). In contrast, the immunity components exhibited no significant changes in fish treated with 2 ml LEO/kg diet after exposure (P>0.01). The expression of iNOS and C3genes significantly reduced in control and fish fed 0.5, 1 and 4 ml LEO/kg diet in response to malathion (P<0.05). Furthermore, the expression of these genes showed no significant changes in fish fed with 2 ml LEO/kg diet after exposure (P>0.01). The findings of the present study suggested an immunoprotective role for dietary LEO at optimized dietary concentrations of 1 and 2 ml LEO/kg diet against oxidative stress and toxicity induced by malathion. Nevertheless, LEO at high dietary concentration (4 ml/kg diet) had reducing effects on the fish immunity.

A simple, rapid, and low‐cost method for preparation of Co3O4nanoparticles (Co3O4‐1 and Co3O4‐2) using solid‐state calcination of mixture of Co(NO3)2∙6H2O and salicylic acid (1:1 weight ratio) at two different temperatures of 500 and 600°C is reported. The morphologies and structure of the as‐prepared Co3O4nanoparticles were characterized using X‐ray diffraction (XRD) and transmission electron microscope (TEM). In addition, we tested them as an anode material for lithium‐ion batteries. The cycling stability and electrochemical performance of the as‐prepared Co3O4nanoparticles were excellent. A capacity of ≈1,100 mAh/g was obtained after 50 cycles at 100 mA/g and exhibited stable discharge behavior up to 50 cycles with high rate capability. A simple, rapid and low‐cost method for preparation Co3O4nanoparticles (Co3O4‐1 and Co3O4‐2) using solid‐state calcination of mixture of Co(NO3)2 · 6H2O and salicylic acid (1:1 weight ratio) at two different temperature of 500 and 600 °C is reported. The morphologies and structural of the as‐prepared Co3O4nanoparticles were characterized using XRD and TEM. In addition, we tested them as an anode material for lithium‐ion batteries. The cycling stability and electrochemical performance of the as‐prepared Co3O4nanoparticles, were excellent. A capacity of ≈ 1100 mAh g‐1 was obtained after 50 cycles at 100 mA g‐1 and exhibited stable discharge behavior up to 50 cycles with high rate capability.

Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality and high-performance solid materials. The process is often used in the semiconductor industry to produce thin films. Microfabrication processes widely use CVD to deposit materials in various forms, including monocrystalline, polycrystalline, amorphous, and epitaxial. These materials include silicon (dioxide, carbide, nitride, oxynitride), carbon (fiber, nanofibers, nanotubes, diamond, and graphene), fluorocarbons, filaments, tungsten, titanium nitride, and various high-k dielectrics. Chemical deposition takes advantage of the chemical reaction where the product self-assembles and deposits on a suitable substrate. Chemical deposition is commonly used for generating thin nanostructured blend films of crystalline inorganic materials, such as ZnS, CuSe, InS, CdS, etc. Depending on the deposition conditions, several terms have been used, such as chemical bath deposition, CVD, and ECD. Depending on the material and the deposition conditions, different surface morphologies have been obtained, from nanopins to nanotubes to nanorods. Reagents in sedimentary reactions are usually water-soluble ionic compounds. When these compounds are dissolved in water, they separate from each other to form anion and cation ions. If a cation of one compound forms an insoluble compound with an anion of another compound, precipitation occurs. Applications of this method include the removal of heavy metals and anions from wastewater, reducing water hardness, and metal recovery. Synthesis processes occur by chemical deposition based on deposition reactions (substitution), co-precipitation, oxidation–reduction, thermolysis, hydrolysis, polymerization, and condensation. The control of various variables in a synthetic system plays an important role in controlling particle size and morphology. The products of sedimentary processes under various synthetic conditions range from coarse crystals to nanostructured colloidal particles. Co-precipitation chemical methods allow the synthesis of metal nanoparticles, metal oxides, as well as many metal semiconductor compounds. Also, a wide range of properties and characteristics can be achieved by changing the synthesis conditions. The basis of these methods is the preparation of products from soluble precursors using different systems such as electrochemical equipment, microwave radiation, ultrasound, and high-energy beams.

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.

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.

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.

The density functionals M06–2X and B3LYP were exploited for investigating the impact of modifying the surface of a boron nitride nano-tube (BNNT) with the furan molecule in terms of energy, electronics, and geometry. According to the density functional theory (DFT) results, BNNT had a strong interaction with the furan molecule. So, the adhesion of the furan molecule onto the surface of BNNT was consistent with the chemical functionalization. Furthermore, the computed density of states indicated that the electronic features of the BNNT 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 BNNT in contrast with the pristine BNNT. Retaining the electronic features of BNNT and the increased solubility demonstrated that using furan to chemically modify BNNTs could be a useful method to purify them.