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In this work, tin (IV) oxide (SnO2) nanoparticles were synthesized based on Amaranthus spinosus plant. The produced graphene oxide by a modified Hummers' method was functionalized with melamine (mRGO) and used accompanied by natural bentonite (Bnt) and extracted chitosan from shrimp wastes to prepare Bnt-mRGO-CH. This was utilized as novel support for anchoring Pt and SnO2 nanoparticles to prepare the novel Pt-SnO2/Bnt-mRGO-CH catalyst. The crystalline structure, morphology and uniform dispersion of nanoparticles in the prepared catalyst were determined by TEM images and XRD technique. The electrocatalytic performance of the Pt-SnO2/Bnt-mRGO-CH catalyst was evaluated for methanol electro-oxidation through electrochemical investigations including cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry techniques. Pt-SnO2/Bnt-mRGO-CH showed enhanced catalytic activity compared to Pt/Bnt-mRGO-CH and Pt/Bnt-CH catalysts considering its higher electrochemically active surface area, higher mass activity, and better stability for methanol oxidation. SnO2/Bnt-mRGO and Bnt-mRGO nanocomposites were also synthesized and did not show any significant activity for methanol oxidation. The results showed that Pt-SnO2/Bnt-mRGO-CH could be a promising catalyst as anode material in direct methanol fuel cells.

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Nano chitosan was extracted from shrimp wastes. Biotin, as a tumor-targeting agent, and curcumin, as potential carriers of 68Ga, were immobilized on the nano chitosan, and a novel bio-nanocomposite was designed. It was characterized by FT-IR, SEM, TEM, XRD, TGA, and elemental analysis. It seems that the chitosan has a fibril shape with an average size of 70 nm, and the biotin and curcumin are evenly distributed as obtained SEM images. While, the size of Chit/Cur@Biot bio-nanocomposite was between 10 and 20 nm according to the TEM images. Cell cytotoxicity assay, cellular uptake, and fluorescence spectroscopy on A549 lung cancer cells were performed to show the potential applications of this bio-nanocomposite. The obtained results were demonstrated that Chit/Cur and Chit/Cur@Biot bio-nanocomposite exhibit antitumor activity, while, the Chit/Cur@Biot bio-nanocomposite is more effective than Chit/Cur against cancer cell lines at high concentrations. The results of fluoresce microscopy show that fluoresce of Chit/Cur@Biot was much stronger than Chit/Cur in the A549 cell lines. Moreover, the cellular uptake of Chit/Cur@Biot was enhanced when compared with the control group. The potentials of this bio-nanocomposite as anticancer and cancer-detecting agent in nuclear medicine were confirmed.

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Herein, at first, green SnO2@ZnO nanocomposites were synthesized using Calotropis plant extract as an electron transfer material (ETM) to fabricate low-temperature-processed perovskite solar cells (PSCs). Then, the polyaniline (PANI) polymer was applied as an efficient additive to improve perovskite film quality. Under the effects of the small content of PANI additive, the quality of perovskite films is enhanced, which showed higher crystallinity in (110) crystal plane; also, the perovskite grains were found to be enlarged from 342 to 588 nm. The power conversion efficiency (PCE) of the prepared PSCs with SnO2@ZnO.PANI nanocomposites electron transfer layer (ETL) increased by 3.12%, compared with the PCE of SnO2@ZnO nanocomposites. The perovskite devices using SnO2@ZnO.PANI nanocomposites ETL have shown good stability during 480 h of tests. Furthermore, the optimal PSCs were fabricated by the mp-TiO2/SnO2@ZnO.PANI nanocomposites as ETL, which has a power conversion efficiency of 15.45%. We expect that these results will boost the development of low-temperature ETL, which is essential for the commercializing of high-performance, stable, and flexible perovskite solar cells.

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In the present study, an eco-friendly process was made for the rapid synthesis of silver nanoparticles using aqueous leaf extract of Hibiscus sabdariffa. The process was characterized by Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible and X-ray diffraction (XRD). These green silver nanoparticles (NPs) were used for mitigating the adverse effects of salinity on seed germination and growth parameters in plants. Accordingly, two experiments were conducted. In the first experiment, seven concentrations of green silver NPs and nine levels of NaCl:CaCl were apptoed on seeds for germination, and their effects were evaluated. In the second experiment, three concentrations of green silver NPs and NaCl were hypothesized to affect plant growth parameters. Seed germination, plant height, leaf, and root fresh and dry weights, as well as relative water content (RWC), decreased significantly under salt stress. However, green silver NPs intervened by alleviating the adverse effects of stress. Accordingly, green silver NPs were beneficial due to (1) activation of the antioxidant system by enhancing antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD), and superoxide dismutase (SOD); (2) increase in the amounts of proline, soluble sugars and carbohydrates for osmoprotection; (3) improvements in flavonoid and anthocyanin contents. Real-time PCR showed that flavonoid and anthocyanin contents increased because of higher expressions in chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), and anthocyanidin synthase (ANS) genes. In conclusion, green silver NPs offered an eco-friendly application for further research on agricultural development.

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A novel bio-nanocomposite was developed by incorporating the extracted nanochitosan from shrimp wastes with Schiff base cobalt complex (Chit-Co complex). The phytosynthesis of Chit-Co complex/Ag bio-nanocomposite was designed utilizing Chit-Co complex at the presence of Ferulago angulate extraction and characterized by AFM, SEM, EDAX, TEM, FT-IR, and elemental analysis. The radioprotective application of this bio-nanocomposite on human lymphocyte cells was evaluated using micronucleus (MN) assay. Total antioxidant activities of it were evaluated using FRAP and DPPH assays. Chit-Co complex/Ag bio-nanocomposite significantly decreased the frequency of micronuclei in human lymphocytes exposed to ionization irradiation (IR). The highest protection was observed at 200 µg/ml. Also, maximum antioxidant activities of bio-nanocomposite were provided at the same dose. These data exhibit the radioprotective effect of a bio-nanocomposite based on wastes of living organisms can be an excellent radioprotective agent, which can protect the normal cells of human against the genetic damage by IR.

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Engineering bioscaffolds for improved cutaneous tissue regeneration remains a healthcare challenge. To help address this problem, we report on the fabrication and characterization of electrospun polyvinyl alcohol and chitosan (PVA/Chit) nanofiber mats loaded honey and Nepeta dschuparensis plant for faster wound healing applications. The morphology of nanofiber mats was examined by SEM and TEM. The physicochemical and thermal stability characterizations were done by FT-IR and TGA/DTA, which reveal the presence of honey and desired plant into the nanofibers. PVA/Chit@Nep/Hon was investigated for wound healing therapy as a potential therapeutic agent. The in vivo wound healing studies on the rats for 21 days revealed the wound healing faster within three weeks by the incorporation of honey and plant into the nanofiber mats and hence these nanofiber mats show great potential in acute and chronic wound healing applications.

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In this paper, the first bio-nano colloid including manganese oxide nanoparticles and copper nanocomplex in the presence of Amaranthus spinosus as one unwanted plant was prepared (Mn3O4/CuL bio-nanocolloid). As-prepared bio nanocolloid was analysed completely by different techniques such as FT-IR, ICP-AES, SEM, EDX, TEM and elemental analysis to have the size, structure, morphology and elements in this compound. This bio-nanocolloid showed high catalytic activity towards green oxidation reactions of alcohols using hydrogen peroxide under solvent free conditions. The longevity, easy and practical recoverability of the solid catalyst was also confirmed for six times. The natural starting material for a long-term stability catalyst preparation, using ideal oxidant (H2O2), solventless and easy work up show the great potential in scalability for actual industries applications.

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MoO3 nanoparticles were obtained using Sesbania sesban. Novel Schiff base ligand and its nanocomplex of copper were synthesized under ultrasonic irradiation. First MoO3/Copper Schiff base complex nanocomposite (NMCS) based on this natural plant was prepared and characterized by TEM, SEM, AFM, FT-IR, TGA, EDAX and elemental analysis. Then atom-efficient and selective oxidation of alcohols using hydrogen peroxide catalyzed by NMCS bio-nanocomposite under ultrasonic irradiation was reported. Structurally diverse set of alcohols was transformed into desired aldehyde and ketone products with high conversion and excellent selectivity under solvent free conditions. Products were isolated easily from green media, and the catalyst could be reused six times without any appreciable decrease in catalytic activity and selectivity.

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Extracted microcrystalline cellulose from Carthamus tinctorius plant was oxidized by sodium metaperiodate and a novel molybdenum schiff base complex was supported on this natural cellulose (MoSMC@MC). Then, micro biopolymer silver/ immobilized molybenum complex on natural cellulose (Ag/MoSMC@MC) was synthesized at the presence of Sesbania sesba plant and charaterized by SEM, FT-IR, TGA, and EDAX. The catalytic efficiency of Ag/MoSMC@MC was exploited as a heterogenous bio-catalyst in the selective oxidation of alcohols. The reactions were conducted using catalytic amounts of Ag/MoSMC@MC and t-BuOOH under solvent free conidtion to obtain desired aldehydes and ketones in high yields and excellent selectivity. Long-term stability and reproducibility in consecutive runs were feature of this microcomposite. At second part of this work, a novel strategy was reported to obtain green nanocomposites. Herein, addition of silver nitrate to plant solution led to the decomposition of the organic to inorganic polymer. As results, MoO3/Ag nanocomposite was prepared and its characteristics were investigated using TEM, and XRD to confirm the shape and structure.

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We present a mild catalytic method to oxidize PAHs and, in particular, pyrene. The pyrenediones are much better electron acceptors than benzoquinone in the gas phase and present similar accepting abilities in solution.

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