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Physicochemical characteristics of three type biodiesel feedstock and diesel engine parameters fuelled with graphene oxide (GO) nanoparticles addition in diesel/biodiesel blends have been investigated. Three types of oilseeds, namely Evening primrose (Oenothera lamarckiana), the fruit of Tree of heaven (Ailanthus altissima) and Camelina (Camelina sativa), were selected as suitable resources for Iran. The result showed that the Tree of heaven contains 38% oil which is higher than the Evening primrose (26%) and Camelina (29%). Physicochemical properties of the oils showed that the viscosity of the Camelina oilseeds was less than the Tree of heaven oilseeds and Evening primrose oilseeds. Therefore, in terms of viscosity, the Camelina oilseeds is preferable. Experimental results showed that the biodiesel from all three types of oilseeds are consistent with the ASTM biodiesel standards. However, Camelina biodiesel has better physicochemical properties than another feedstock. Therefore, biodiesel of Camelina oil can be an appropriate alternative to diesel fuels in Iran. Performance and emission parameters of diesel engine fuelled with graphene oxide (GO) nanoparticles addition in three biodiesel resources compared with diesel. A reduction in UHCs, CO, and BSFC with a penalty of increased NO x emissions was realized with all graphene oxide (GO) nanoparticles addition in diesel/biodiesel blends. Also, with Camelina biodiesel, the power increased. • Tree of heaven contains 38% oil which is higher than the Evening primrose (26%) and Camelina (29%). • Produced biodiesel from three feedstocks passed the biodiesel ASTM standards. • Camelina oil biodiesel can be a suitable alternative for fossil fuels. • Graphene oxide (GO) nanoparticles decrease the UHCs, CO, and BSFC of diesel engine. [ABSTRACT FROM AUTHOR]

In order to explore the research trends and hotspots related to the treatment of heavy metals in wastewater by graphene and its composites, this study collected information on 511 publications from the Science Citation Index-Expanded (SCIE) and conducted a quantitative and visual analysis. The article on the adsorption of heavy metals in wastewater by graphene and its composites first appeared in 2006 and continued to grow since 2011. It broke through 100 articles for the first time in 2016 and the overall trend is on the rise. The 511 articles were published in 185 journals, of which RSC Advances is the most dynamic journal, and Journal of Materials Chemistry A is the most authoritative journal. Asian authors published about 87.14% of papers, and China, Iran, and India played a leading role compared with other countries. The University of Chinese Academy of Sciences is the largest research institution for the adsorption of heavy metals in wastewater by graphene and its composites. Hot keywords are "heavy metal removal," "water sample," "recent advance," "reusable adsorbent," "graphene-based material," and "composite nanosheet." Combined with keywords and cluster analysis, the chemical modification of graphene oxide has become a hot research direction for graphene materials to remove heavy metals from wastewater. Among them, MnFe2O4-graphene composite is a hot spot for graphene modification. In general, HNO3, HCl, and EDTA are desorption reagents for graphene and its composites. [ABSTRACT FROM AUTHOR]

Water pollution is one of the most universal problems oppressing people throughout the world, while adsorption is the most widely used method to remove contamination from water. In this paper, we proposed graphene oxide as a suitable adsorbent for the removal of ametryn from Karoon River water, drainage and water obtained from washing of soil samples of sugarcane farm (Hakim Farabi Agro-industrial. Co. Khuzestan province, Iran). To this end, the concentration of ametryn was quantitatively measured by high-performance liquid chromatography (HPLC). The response surface methodology (RSM) was used for the optimization of the effects of four important parameters influencing the removal efficiency of the proposed method. Experimental and modeling results showed that graphene oxide effectively adsorbed ametryn with maximum sorption capacity of 47.2 mg g−1. The adsorption process with ametryn was found to be fitted to pseudo-second-order kinetic equation and the Langmuir adsorption isotherm model. Moreover, the experimental results indicated that GO had good adsorption ability for the removal of ametryn from water and soil samples. [ABSTRACT FROM AUTHOR]

Background and Aim: Background and Aim: Photodynamic therapy is a minimally invasive approach to cancer, which is used to combine non-toxic photosensitizer and visible light to produce reactive oxygen species and destroy tumors. This study aimed to investigate the cytotoxicity effect of Graphene Oxide (GO)as an organic matter with many oxygen groups on photodynamic on destroying cancer cells. Materials and Methods: This study was performed on breast cancer cells (MCF-7) in vitro. The study groups included the first group of drug with different concentrations of graphene oxide (333.3, 285.7, 230.7, 166.6, 90.9, 47.6 μg/ml), the second group co-drug and laser light irradiation and the control group consisted of cells treated only with laser irradiation and the control group was treated with no treatment. Cells were exposed to visible laser irradiation (405 nm) at 0.1 W / cm2. Cell viability was determined by MTT assay. Ethical Considerations: This study with research ethics code SBU/S.1397.46A has been approved by research ethics committee at Shahid Behesht University of Tehran, Iran. Findings: The results of in vitro experiments showed that the dark toxicity of graphene oxide at concentrations of less than the 90.9 μg / ml concentration had no significant effect on cancer cells. Also, laser light alone don’t has toxic effect on cells. But graphene oxide-mediated dynamic light therapy has reduced the bioavailability of cancer cells on average by 21% over dark toxicity. Results are presented as mean of three independent replications, standard error, and p< 0.05 was considered significant. Conclusion: In this study, graphene oxide is fully biodegradable at concentrations below a certain value, but with increasing concentration, the toxicity effect increases. With exposure to light and graphene oxide, viability decreses that it is more effective for in vivio studies. [ABSTRACT FROM AUTHOR]

• The D-SPME method based on magnetical extraction were developed for biogenic amines. • Simultaneous analysis of BA was performed in a total of 40 smoked fish samples. • Thirty-six out of 40 samples exceeded an acceptable level of histamine (50 mgKg−1). Herein, a dispersive solid phase microextraction (D-SPME) approach based on magnetic nanoabsorbents was developed for the simultaneous extraction of histamine, cadaverine, putrescine, and tyramine in smoked fish. The desired magnetic nanocomposite was prepared with surface modification of Fe 3 O 4 nanoparticles with graphene oxide via surface reversible addition fragmentation chain transfer (RAFT) copolymerization. Preparation, size, morphology, surface functional groups and magnetic properties of as-synthesized nanocomposite was characterized. The obtained results showed acceptable r2 values (≥0.9949) for all analyte as well as good recovery (>98.36), repeatability (RSD%<3.57), and reproducibility (RSD%<5.16) of the developed method. The developed method was successfully employed to estimate four biogenic amines in 40 samples from different species of smoked fishes available in northern Iran. Thirty-six out of 40 samples exceeded an acceptable level of histamine (50 mg Kg−1). Cadaverine and putrescine were founded at a higher level, while tyramine was detected at the lowest level in comparison with other BAs (<11 %). [ABSTRACT FROM AUTHOR]