A series of Ni/SBA-15 catalysts was prepared by impregnation method. Effect of NiO content (3060 mass%), calcination time (0.52 h at 800°C), and reduction time (12 h at 800°C) on catalytic performance in combined steam and CO 2 reforming of CH 4 (CSCRM) was studied. N 2 physisorption measurements, powder X-ray diffraction, Hydrogen temperature-programmed reduction, CO 2-temperature-programmed desorption, and transmission electron microscopy were used to investigate physico-chemical properties of the catalysts. The catalytic performance of Ni/SBA-15 in CSCRM was assessed in the temperature range of 550800°C. The results revealed suitable time for calcination and reduction being 0.5 h and 1.5 h, respectively. After these treatments, 40 mass% NiO/SBA-15 catalyst was more active and exhibited higher activity than others. At 750°C, conversion of CH 4 and CO 2 on this catalyst in CSCRM was 91.05% and 78.11%, respectively. High surface area, better reducibility, and good affinity with CO 2 contribute to the high performance of this catalyst.

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In this work, a series of 10 wt% NiO/CeO2 catalysts (Ni/Ce) promoted by V2O5 with content varying in the range of 0–0.5 wt% was prepared by the co-impregnation method. The characteristics of the catalysts were investigated by several techniques including N2 physisorption (BET), X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), EDS mapping, carbon dioxide temperature-programmed desorption (CO2-TPD), and hydrogen temperature-programmed reduction (H2-TPR). The activity of the catalyst was studied in the micro-flow system in a temperature range of 550 °C–800 °C, the feedstock composition CH4/CO2/H2O of 3.0/1.2/2.4 and the weight hourly space velocity (WHSV) of 30,000 ml.h−1.g−1. Adding V2O5 additive, on the one hand increases the reducibility and basicity of Ni/Ce catalyst, on the other hand reduces oxygen vacancies and increases the crystal size of CeO2, leading to various effects on catalyst activity depending on its content. Ni/Ce catalyst promoted with 0.3 wt% of V2O5 was the best among tested ones, on which at reaction temperature of 700 °C, the conversion of CH4 and CO2 reached 97% and 77% respectively, and the molar ratio of H2/CO was 2.1. Meanwhile, on non-promoted Ni/Ce catalyst, the corresponding quantities were 83%, 62% and 1.9, respectively. It is important to note that performance of both was stable for more than 30 h thanks to the better resistance to coke deposition and structural stability.

A rapid way of synthesizing silver nanoparticles (AgNPs) by treating Ag+ ions with a green Fortunella Japonica (F.J.) extract as a combined reducing and stabilizing agent was investigated. The reaction solutions were monitored using UV-Vis spectroscopy, the size and shape of crystals were determined by scanning electron microscopy and transmission electron microscopy, the crystalline phases of AgNPs were presented by X–ray diffraction, and the relation of nanoparticles with Fortunella Japonica extract was confirmed using fourier transform infrared spectroscopy. The results indicated that no formation of AgNPs had taken place in the dark during 24 hours at room temperature and 40 oC. Meanwhile, it was found that the rate of AgNPs formation increased rapidly under the sunlight. The effects of the synthesis factors on the AgNPs formation were investigated. The suitable conditions for the synthesis of AgNPs using F.J. extract were determined as follows: F.J. extract was mixed with AgNO3 1.75 mM solution with the volume ratio of 3.5 AgNO3 solution/1.5 F.J. Extract, stirred 300 rpm for 150 minutes at 40 oC under sunlight illumination. At these conditions, AgNPs showed high crystalline structure with the average size of 15.9 nm. The antibacterial activity of silver nanoparticles was determined by agar well diffusion method against E. coli and B. subtilis bacteria. The green synthesized AgNPs performed high antibacterial activity against both bacteria.

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In this paper, TiO 2 and Fe-doped TiO 2 had been prepared by the sol-gel method. Physico-chemical characteristics of the catalysts were determined by the methods of BET Adsorption, XRD, FT-IR, and UV-Vis spectroscopies. Experimental results showed that the The modification of TiO 2 catalyst with Fe led to reducing the crystallite size and PZC, and extending the spectrum of photon absorption to the visible region. The activity of obtained catalysts for photodegradation of cinnamic acid (CA) solution in the presence of various oxidizing agents (O 2 , O 3 and H 2 O 2 ) was investigated and the optimum reaction conditions were identified. It follows that the addition of Fe additive is able to reduce the optimal catalyst concentration 3-5 times and increase the catalytic activity. It was found that O 3 and H 2 O 2 agents showed the higher efficiency for cinnamic acid photodecomposition than usual O 2 . In optimum conditions, after 90 minutes reaction, the conversion of cinnamic acid in the solution achieved 58.5, 77.7 and 83.1% on TiO 2 and 85.7, 82.8 and 89.4% on Fe-TiO 2 in the presence of O 2 , O 3 and H 2 O 2 respectively.

Silver nanoparticles (AgNPs) were synthesized from aqueous AgNO 3 precursor via an effective and ecofriendly method using Lemon Citrus Latifolia (LCL) extract as the reducing and stabilizing agent under sunlight condition. The AgNPs formation was confirmed by ultraviolet-visible absorption spectroscopy at the wavelength of 400450 nm. The appropriate conditions and positive effect of direct sunlight on the AgNPs preparation were revealed clearly. The synthesized AgNPs were characterized using multitechniques X-ray diffraction revealed that AgNPs had the crystalline nature of face-centered cubic structure. Scanning electron microscopy and transmission electron microscopy showed the obtained AgNPs was spherical and the size distribution was uniform with the nanosize of 424 nm. The obtained AgNPs solution showed an effective antibacterial activity against E. coli, B. subtilis and B. cereus with the average diameter of inhibition zones over 15 mm.

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