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Salt stress is of the most detrimental abiotic stress factors on either crop or non-crop species. Of the strategies employed to boost the performance of the plants against harmful impacts of salt stress; application of novel nano-engineered particles have recently gained great attention as a promising tool. Octa-aminopropyl polyhedral oligomeric silsesquioxanes nanoparticles (OA-POSS NPs) were synthesized and then a foliar-application of OA-POSS NPs were carried out on sweet basil plants subjected to the salt stress. In that context, interactive effects of OA-POSS NPs (25, 50 and 100 mg L-1) and salinity stress (50 and 100 mM NaCl) were assayed by estimating a series of agronomic, physiological, biochemical and analytical parameters. OA-POSS NPs decreased the harmful effects of salinity by increasing photosynthetic pigment content, adjusting chlorophyll fluorescence, and triggering non-enzymatic (phenolic content) and enzymatic antioxidant components. The findings suggested that 25 mg L-1 OA-POSS NPs is the optimum concentration for sweet basil grown under salt stress. Considering the essential oil profile, estragole was the predominant compound with a percentage higher than 50% depending on the treatment. In comparison to the control group, 50 mM NaCl did not significantly affect estragole content, whilst 100 mM NaCl caused a substantial increase in estragole content. Regarding OA-POSS NPs treatments, increments by 16.8%, 11.8% and 17.5% were observed following application with 25, 50 and 100 mg L-1, respectively. Taken together, the current study provides evidence that POSS NPs can be employed as novel, 'green' growth promoting agents in combating salt stress in sweet basil.

Biomass derived carbon materials have advantages of cost and availability over other carbon materials. However, handful researches based on biomass derived carbon materials have been conducted to explore the oil–water adsorption potential. In this study, we demonstrated that the egg yolk derived carbon material in the presence of iron nanoparticle can be used as a cost-effective absorbent to oil–water separation. Carbon-sponge composite was prepared by dip coating method and showed high adsorption capacity (from 28 to 87 times its original weight) for broad spectrum of organic solvents and oil. These results show evidence that the egg yolk derived carbon material is suitable candidate for the construction of hydrophobic sponge in large-scale and low-cost for removal of oil contaminants from aqueous medium.

Two novel heterogeneous hybrid catalysts were successfully synthesized using octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS) and ionic liquids, followed by immobilization of Cu and Ag nanoparticles. The obtained hybrid catalysts, Cu@POSS-ILs and Ag@POSS-ILs, were characterized using FT-IR, SEM, EDX, TEM, XRD and TGA. Catalytic studies demonstrated that Cu@POSS-ILs was an excellent catalyst for click reaction in aqueous medium. Furthermore, Ag@POSS-ILs was also exhibited to be an active catalyst for 4-nitrophenol (4-NP) reduction. Simple preparation and easy catalysts recovery and recyclability of Cu@POSS-ILs and Ag@POSS-ILs for at least 3 and 6 runs, respectively, without loss of catalytic activity could be considered as important advantageous from catalytic application point of view.

In the present work, N-rich activated carbon was synthesized using hydrothermal carbonization of egg white biomass in the presence of sucrose, followed by chemical activation and magnetization of hydrochar in the presence of iron (II) and (III) at NaOH solution. The results showed that the sucrose has a critical role in hydrochar yield by increasing of sucrose content. This claim also proved by SEM analysis, which hydrochar morphology was changed from the layered to fused carbon spheres morphology that confirmed the increasing of nucleation site. The materials were characterized with VSM, SEM, CHN, FTIR, Raman spectroscopy and XRD techniques. Capacity of prepared magnetic activated carbon was studied in the methylene blue adsorption from aqueous solution. The influence of different parameters, such as various activation methods of carbon, carbon amount, pH, temperature, contact time and initial dye concentration, on the adsorption of methylene blue was studied. Simultaneously chemical activation and magnetization of hydrochar provided an N-rich activated carbon with high adsorption capacity rather than chemical KOH activation method.

Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic acid. The as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m2·g−1. Experimental results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 min. This is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH NPs. These NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.

Hexagonal core–shell SiO2[–MOYI]Cl–]Ag nanoframeworks were synthesized via surface modification of hexagonal silica nanoparticles prepared from perlite (EP) as a cheap and abundant raw material. The prepared samples were well characterized by X-ray diffraction powder (XRD), energy dispersive X-ray (EDX), diffuse reflectance spectroscopy (DRS), Brunauer–Emmett–Teller (BET) specific surface area analysis, fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). The XRD patterns confirmed that Ag and AgCl crystalline phases were successfully loaded on the surface. The TEM images were also implied that the nanoparticles have hexagonal shape with the average size of 50–80 nm. Photocatalytic properties were evaluated by degradation of acid blue 92 (AB92), two semivolatile organic compounds (SVOCs) i.e., 4-methoxy-2nitrophenol (4Mx2Np) and 3-methyl-4-nitrophenol (3M4Np), and Staphylococcus aureus (S. a) gram positive bacteria under visible light. The kinetics and mechanism of the photocatalytic pathways were also studied and the results were discussed. According to the obtained results, the photocatalyst was incredibly able to degradethe contaminants under visible light. Recycling experiments described the high capacity of the prepared sample for the repeated treatment of wastewaters.The TEM images of the treated bacterial cell walls after the reaction time were also used to clarify the antibacterial activity of the samples.

Multi wall carbon nanotubes have been successfully exploited as growth regulator for manipulation of plant development. Also, nanoparticles are gradually involved in target delivery systems as the carrier of hormones. Polyamines and their derivations play crucial roles in plant growth and development. Take the mentioned subjects into consideration, putrescine anchored carbon nanotube which had been labeled with fluorescein was synthetized in this study. A set of physiological and morphological parameters were assessed in an attempt to examine the usage potential of de novo synthetized nanotube in terms of plant in-vitro culture. For this purpose, the nanotube was applied onto the in-vitro plantlets of Malus niedzwetzkyana in three concentrations (0, 50 and 100 mg/l). Localization of the nanotube in the plantlets was accomplished using fluorescence microscopy. Bio-imaging of tissues indicated the existence of nanotube in nearly all studied organs. Application of the nanotube at both concentrations (50 and 100 mg/l) increased the rate of leaf formation and speeding up the plastochron. Also, proliferation of the plantlets was enhanced using the nanotube. The levels of the photosynthetic pigments, including chlorophyll a, b and carotenoids increased following application of the nanotube. Glutathione peroxidase activity was significantly affected by the nanotube. However, polyphenol oxidase and peroxidase were not influenced by the nanotube. Stomatal density was increased by treatment of the plantlets with the nanotube. Representing geometrical transformation of shape as a thin plate spline revealed that the nanotube effectively increased longitudinally of stomata and changes their aspect ratio.

A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn2+. It showed high selectivity and sensitivity for Zn2+ion in aqueous solution over other metal ions such as Li+, Na+, Ca2+, Mg2+, Al3+, Cd2+, Co2+, Cu2+, Hg2+, Ni2+, Pb2+, Fe2+, Fe3+and Cr3+. Due to the linearity of the emission intensity toward Zn2+ concentration, fluorescent technique could be used for the detection of Zn2+ ion even at very low concentrations.

In this study, a new series of hybrid hydrogels based on poly(N-isopropyl acrylamide-co-itaconic acid) containing octavinyl polyhedral oligomeric silsesquioxane (OV-POSS) nontoxic cross-linker with different feed ratio were fabricated via free radical copolymerization. The resulted hydrogels were characterized by FT-IR, SEM, XRD and TGA analysis. Various parameters such as time, temperature, pH and salt effects were investigated on the swelling as well as dye removal properties of hybrid hydrogels. The adsorption experiments showed that the maximum adsorption capacity accrued at pH 11 for methylene blue. Adsorption kinetics was elucidated by both pseudo-first-order and pseudo-second-order kinetic models under different conditions. Also, adsorption isotherm of the adsorption of methylene blue on poly(NIPAM-co-IA)/POSS8 adsorbent was investigated using Langmuir, Freundlich, Redlich–Peterson and Sips models, in which the experimental data were fitted well with Langmuir, model.

A novel nanosensor based on CdSe quantum dots (QDs) capped with 8-hydroxyqunoline (HQ) was developed for Al3+ ions determination in aqueous solutions. The method is based on the fluorescence enhancement of the HQ functionalized QDs in the presence of Al3+ ions, due to the strong interaction between Al3+ and HQ. Prepared nanosensor exhibited an acceptable selectivity and sensitivity for Al3+ ions in the presence of other metal ions. Plot of Log(I/I0) against Log[Al3+] shows a good linearity in the range of 0.02–3.0 mM, and the method could be used for detection of Al3+ ions concentration in aqueous solutions.

Studies on nano-sized particles have been the range for the past 10–15 years. With rapid growth of metal oxide nanotechnologies during the last decades, the application of this material in the field of catalysis has become a substantial research area. In the past decades, the utilization of transition metal oxide nanoparticle catalysts for industrial application in the synthesis of important chemical intermediates has been investigated by industrial and academic communities. Compared to other catalysts, one of the outstanding properties of metal oxide nanoparticles in catalysis is represented by the high selectivity which allows discrimination within chemical groups and geometrical positions, favoring high yields of the desired product. This review is devoted to dealing with the application of transition metal oxide nanoparticles as catalyst for oxidations of sulfides, alcohols, olefins, and alkanes toward the synthesis of a variety of organic compounds, such as sulfoxides, aldehydes and ketones, carboxylic acids, epoxides and alcohols.

A nanosensor based on p-nitrophenyldiazenylphenyloxadiazole (NDPO) capped CdSe quantum dots (QDs) was developed for Cd2+ ions in aqueous solutions. The nanosensor exhibited a high selectivity for cadmium ions and showed linear correlation with Cd2+ ions concentration in the range of 0.05–1.0 mmol/L. The prepared NDPO capped CdSe QDs were characterized by TEM, SEM, EDX, and FTIR techniques.

In the present study, poly(acrylamide-co-itaconic acid) hybrid nanocomposites were synthesized via free radical copolymerization method. Octavinyl polyhedral oligomeric silsesquioxane (OV-POSS) with different weight ratio (0, 4, 8, 12 and 14 wt%) was utilized as a cross-linker. Dye adsorption properties of the as-prepared hybrid nanocomposites were investigated for crystal violet (CV) elimination from aqueous solution. The effect of various parameters, such as OV-POSS content, adsorbent amount, pH, temperature, contact time and initial dye concentration, on the adsorption of CV was studied. Moreover, adsorption kinetic, isotherm and the thermodynamic of the CV adsorption on the so-called hybrid nanocomposites were studied.

Fe3O4@SiO2 core–shell magnetic nanoparticles (MNPs) were prepared by chemical coprecipitation of FeCl3·6H2O and FeCl2·4H2O in alkaline solution, followed by silylation using triethoxy silane, and then by treatment with 3-aminopropyltriethoxysilane. The corresponding MNPs were coated with carboxymethyl cellulose (CMC) by amide formation between carboxyl groups of CMC and amine functional groups of nanoparticles. The structure of MNPs was characterized by FT-IR, SEM, EDX, TEM, XRD, VSM and TGA analysis. CMC-coated Fe3O4@SiO2 magnetic nanoparticles were used as an efficient adsorbent for the removal of methylene blue (MB, a cationic dye) from aqueous solutions. The impact of various factors such as adsorbent dosage, pH, initial concentration of MB, temperature and contact time were investigated. The kinetic, isotherms, and thermodynamic parameters of adsorption were also studied.

In this investigation, the preparation of novel Halloysite-based chitosan/oxidized starch (Hal/CTS/OSR) Hybrid bionanocomposite hydrogels is described. The obtained hybrid hydrogels were characterized by using FT-IR, SEM, XRD, TGA and DTG techniques. In addition, the efficiency of hydrogels as drug delivery systems was studied. The results demonstrated that depending on experimental parameters, such as the ratio of CTS/OSR, and the type of Hal nanotubes (modified or unmodified), the hydrogel properties can be affected and modulated significantly. 74.3%, 71.2% and 69.45% MTZ release were observed for CTS/OSR/mHal 10, CTS/OSR and CTS/OSR/Hal 10 respectively.

A new method based on CdSe quantum dots (QDs) was developed to detect 185delAG mutation in BRCA1 gene. In this method P2-NH2 strand was covalently attached to QDs possessing carboxylic acid to provide QD-P2, and its emission was studied against other probs. In the presence of cDNA and P1-NH2, emission of QD-P2 was 85% more intense than just pure bare QD-P2. Moreover, new peak appeared in emission spectrum in higher wavelength which could be associated with formation of more organized shrinked aggregates due to connection between QDs by DNA strands. Partial (35%) increase in the intensity of emission in the presence of mDNA was observed, according to the formation of disorganized aggregates and therefore less rigid system, which is attributed to mutation in DNA strands. The generation of organized small and disorganized aggregates in the presence of cDNA and mDNA, respectively, was approved by DLS analysis and zeta potential measurements.

Vanadium (V) and tungsten (VI) oxoperoxo complexes supported on Fe3O4 magnetic nanoparticles were synthesized and characterized. These compounds are assigned as catalyst 1 (C1: Fe3O4@Gly@r-Py@VO3) and catalyst 2 (C2: Fe3O4@Gly@r-Py@WO3), respectively, and were found to be efficient and reusable heterogeneous catalysts for the oxidation of alcohols and sulfides using H2O2.

A copper-containing polyoxovanadate nanocluster, [(C2H5)4N]4[V8Cu2O24]∙2H2O (1), was synthesized through reaction between the Cu(NO3)2∙3H2O and [(C2H5)4N]4VO3 in the molar ratio 1 : 4. Nanocluster ...

4-nitrophenol (4-NP) is a highly toxic pollutant for aquatic ecosystem and human life. Therefore, the catalytic reduction of 4-NP into useful 4-aminophenol (4-AP) is of interest. In this regard, two heterogeneous nanocatalysts, including Ag@HNTs-ILs and Co@HNTs-ILs were prepared by grafting imidazolium-based ionic liquids (ILs) onto the halloysite nanotubes (HNTs), followed by immobilization of Ag and Co nanoparticles (NPs), and characterized by means of FT-IR, SEM, EDX, TEM and XRD. The catalytic activity of the prepared nanocatalysts was evaluated for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) under environmentally friendly condition. A set of time, temperature, nanocatalyst amount and NaBH4/4-NP molar ratios was screened. The reusability experiments demonstrated that Ag@HNTs-ILs and Co@HNTs-ILs were highly reusable, up to five reduction cycles without considerable changes in the reaction time. As the synthesized hybrid nanocatalysts could be re-collected and reused for various catalytic runs without any significant loss in their catalytic activity, they could be considered very promising nanomaterials from sustainability point of view.

Oxoperoxo tungsten(VI) complex immobilized on Schiff base-modified Fe3O4 super paramagnetic nanoparticles were synthesized and appropriately characterized using FT-IR, XRD, SEM, TEM, EDX, BET, and VSM analysis. The synthesized nanoparticles efficiently catalyzed oxidation of benzylic alcohols with H2O2 as oxidant in high yields, with high to excellent selectivity. The catalyst can be recovered using an external magnetic field and recycled for subsequent oxidation reactions without any appreciable loss of efficiency. The simple preparation, high activity, excellent selectivity, and simple recoverability of the catalyst are advantageous.

Ag nanoparticles were synthesized and stabilized on a polymeric support, poly([Formula: see text]-isopropyl acrylamide-co-itaconic acid)/POSS, by simply reducing Ag[Formula: see text] ions adsorbed in the interior of the polymeric network. The prepared Ag@p(NIPAM-IA)/POSS was used as an efficient and recyclable catalyst for removal of the 4-nitrophenol (4-NP) contaminant by NaBH4-induced reduction to 4-aminophenol (4-AP) in aqueous solution. Different conditions including Ag content and amount of the nanocomposite, and also temperature of the 4-NP reduction were investigated. Also, two kinetic models, zero-order and first-order kinetics, were studied for the reduction of 4-NP to 4-AP.

A new gelator based of oleylamide has been introduced, which was gelled nonpolar hydrocarbon and CCl4 solvents through self-assembly. Also, the gelator formed a two-component hydrogel in combination with SDS, an anionic surfactant. UV-Vis studies revealed that the H-type and J-type aggregation of organogels in hexane and hydrogel in water, respectively. The xerogel, obtained by evaporating the solvent of organogel, selectively gelled and adsorbed oil spills on water surfaces. The effect of the various parameters, including temperature, water acidity and pH on the oil spill adsorption was studied, revealing the high ability of the xerogel to removing the oil contamination from water in up to 10 min. The novelty of this work is the ability of the xerogel to the phase selective gelation of oil without an extra auxiliary and/or heat. Simple synthesis of gelator started with oleic acid from natural resources is a main advantage of the present work.

Biomass conversion to carbonaceous materials and their use in various applications, such as capacitors, catalyst supports, and adsorbents, have attracted considerable attention from the viewpoint of green chemistry. In this regard, chicken egg white is one of the most important biomass, which can act as an in situ nitrogen doping source. In this paper, nitrogen-rich porous carbon material was synthesized from egg white biomass via pyrolysis at 600 °C under nitrogen atmosphere, followed by chemical activation with KOH at 500 °C. The results showed that the as-synthesized porous carbon material has a high content of nitrogen and high surface area, on which nitrogen can tune the surface hydrophobicity–hydrophilicity through interaction with water molecules. Then, the copper nanoparticles were immobilized on the surface of nitrogen-rich activated carbon by a chemical reduction method. Nanocatalyst structure was characterized by elemental analysis, TEM, AFM, Raman, FT-IR, porosimetry and atomic adsorption techniques. Finally, catalytic activity was evaluated for the one-pot synthesis of triazole in aqueous medium. The nanocatalyst offers some advantages such as excellent activity, low loading of catalyst, good yields of products and short reaction times.

In this work, for the first time, we presented a novel design strategy to fabricate a new type of Octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS)-based Alg/PAAm DN gels, consisting of PAAm gel as the first chemical network and Alg/OA-POSS gel as the second chemical-physical network. Incorporation of OA-POSS nanoparticles with various feed ratio into the second network not only led to form strong coordination interactions but also in comparison to the other Alg/PAAm gels demonstrated superior mechanical properties. pH, temperature, contact time and salt effects parameters were studied on the swelling and dye removal properties of the synthesized DN hybrid hydrogels. The adsorption experiments exhibited that 20 mg of Alg/PAAm/OA-POSS1 showed the maximum adsorption capacity for methylene blue (MB) at pH 9 and 11. Dye adsorption kinetics were modeled by the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetic equations under different conditions. Additionally, adsorption isotherms of the adsorption of MB were analyzed.

A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn

Escherichia coli O157:H7 bacterium as a zoonotic pathogen is one of the most important causative agents of foodborne illnesses worldwide. Due to the serious concerns in public health and enormous economic losses in agriculture and food industry, it is very necessary to develop novel technology–based methods for sensitive and rapid detection of this bacterium in contaminated resources. In this study, a sensitive and selective fluorescence DNA nanosensing platform based on graphene oxide (GO) and the 3′ end of eae gene as specific sequence was developed for the detection of E. coli O157:H7. In this platform, fluorescence resonance energy transfer (FRET) process between GO- and FAM-labeled eae gene probe was used for the diagnosis of E. coli O157:H7. Following the immobilization of the eae gene probe on GO, fluorescence emission of FAM was quenched. In hybridization reaction, by adding the complementary DNA, fluorescence emission of FAM was significantly increased and recovered to 93%. The performance of sensor for detection of E. coli O157:H7 genomic DNA was determined 10 pg genomic DNA per 1 ml Tris-HCl hybridization buffer which was significantly more sensitive than PCR method. In conclusion, the results indicated that GO eae gene-based nanosensor has potential to be developed as a rapid and sensitive diagnostic device besides PCR methods for the detection of E. coli O157:H7 bacteria.

The monomer 2-{5-[4-((4-nitrophenyl)diazenyl)phenyl]-1,3,4-oxadiazol-2-ylthio}ethyl acrylate (NDPOE-acrylate) was synthesized in five steps and then copolymerized with N-isopropylacrylamide, leading to a dual pH and temperature responsive polymeric sensor. Obtained copolymer exhibited the lower critical solution temperature only in acidic medium (pH 2) as 32 °C. The UV–vis and fluorescence of copolymer was investigated at different pH values in various temperatures. The UV–vis of copolymer are independent to temperature above pH 4. The copolymer exhibited sensitive fluorescence change towards pH between 2 and 10 at different temperatures.