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The Khorramabad-Zal Highway is a crucial component of the Tehran-Bander Imam Khomeini axis, which holds significant economic importance in the country. Hence, this study focuses on assessing the risk of landslides in the Khorramabad-Zal Highway through the utilization of geographic information system (GIS). To assess the landslide hazards zonation in this study, the hierarchical analysis method (AHP) was employed. Field studies, observations, and geological conditions were considered to identify 10 factors that influence landslide occurrences. These factors include lithology, slope, aspect, distance from fault lines, land use, climate, altitude, distance from rivers, distance from drainages, and rainfall. Through the AHP method within a GIS environment, each parameter was weighted and maps were generated to represent their individual contributions. In conclusion, the integration of various layers has facilitated the creation of a comprehensive landslide hazard zoning map for the designated study area. The analysis of this map revealed that approximately 54% of the surveyed region possesses a high and very high potential for landslides. [ABSTRACT FROM AUTHOR]

This study deals with the preparation of a novel biomaterial by incorporating the hematite α-Fe2O3 onto crushed leaves of the Washingtonia filifera palm tree in their raw state and in extracted cellulose from the same plant. The incorporation of α-Fe2O3 was accomplished by hydrothermal route at 200 °C. The palm leaves, extracted cellulose, and synthesized products were characterized by thermal analysis (TG) and FT-IR spectroscopy. The latter revealed peaks at 524 and 449 cm−1 for the synthesized material, attributed to vibrational deformation of the inorganic Fe-O bond. In contrast to the TG profile of raw palm leaves, the thermogram of the composite degrades in a single step at 343 °C. This one-step decomposition clearly indicates the chemical modification of our cellulose matrix and confirms the successful incorporation of the hematite α-Fe2O3 into the lignocellulose. The second part is devoted to α-Fe2O3 working as sensitizer in photocatalysis, it was characterized optically (Eg= 1.94 eV) and electrochemically with a flat band potential of −0.53 VSCE. The conduction band (−0.73 VSCE) is more cathodic than the potential of the O2/O2•− couple (−0.52 VSCE) and should reduce dissolved oxygen into reactive O2•− radical. The as-prepared materials were successfully tested in the photocatalytic degradation of Rh B (10 ppm) and the result gave an abatement of 60% on α-Fe2O3/lignocellulose under visible light irradiation (LED lamp) with a flux of 23 mW cm−2. The kinetic obeys a first-order model with a half photocatalytic-life of ∼ 7 h. [ABSTRACT FROM AUTHOR]

Mehdi Doosti-Telgerd,1 Fatemeh Sadat Mahdavi,2 Farzad Moradikhah,3 Mohammad Porgham Daryasari,1 Rahimeh Bayrami Atashgah,1 Banafsheh Dolatyar,4 Hamid Akbari Javar,5 Ehsan Seyedjafari,2 Iman Shabani,3 Ehsan Arefian,6 Farhood Najafi,7 Yaser Abdi,8 Mohsen Amini9 1Department of Pharmaceutical Biomaterials, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 2Department of Biotechnology, University of Tehran, Tehran, Iran; 3Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran; 4Department of Cell and Developmental Biology, School of Biological Sciences, College of Science, University of Tehran, Tehran, Iran; 5Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 6Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran; 7Department of Resin and Additives, Institute for Color Science and Technology, Tehran, Iran; 8Department of Physics, University of Tehran, Tehran, Iran; 9Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, IranCorrespondence: Hamid Akbari JavarDepartment of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box: 1417614411, Tehran, IranTel +98 2164122205Email akbarijo@tums.ac.irObjective: The aim of this study is to fabricate functional scaffolds to gene delivery bone morphogenetic protein-2 (BMP-2) plasmid for bone formation in bone tissue engineering.Methods: Dendriplexes (DPs) of generation 4 polyamidoamin (G4-PAMAM)/BMP-2 plasmid were prepared through microfluidic (MF) platform. The physiochemical properties and toxicity of DPs were evaluated by DLS, AFM, FESEM and MTT assay. In order to create a suitable environment for stem cell growth and differentiation, poly-l-lactic acid (PLLA) and poly-l-lactic acid/poly (ethylene oxide) (PLLA/PEO) scaffolds containing hydroxyapatite nanoparticles (HA) and DPs were fabricated by the electrospinning method. The osteogenic potency of the scaffolds on human adipose tissue-derived mesenchymal stem cells (hASCs) was investigated.Results: The results revealed that tuning the physical properties of DPs by adjusting flow parameters in microfluidic platform can easily improve the cell viability compared to conventional bulk mixing method. Also, the result showed that the presence of HA and DPs in PLLA/PEO scaffold enhanced alkaline phosphatase (ALP) activity and increased the amount of deposited Ca, as well as, related to osteogenesis gen markers.Conclusion: This study indicated that on using the MF platform in preparation of DPs and loading them along with HA in PLLA/PEO scaffold, the osteogenic differentiation of hASCs could be tuned.Keywords: microfluidic, dendriplex, nanofibrous scaffolds, bone tissue engineering

Monte Carlo continuous time random walk simulation is used to study the effects of confinement on electron transport, in porous TiO2. In this work, we have introduced a columnar structure instead of the thick layer of porous TiO2 used as anode in conventional dye solar cells. Our simulation results show that electron diffusion coefficient in the proposed columnar structure is significantly higher than the diffusion coefficient in the conventional structure. It is shown that electron diffusion in the columnar structure depends both on the cross section area of the columns and the porosity of the structure. Also, we demonstrate that such enhanced electron diffusion can be realized in the columnar photo-electrodes with a cross sectional area of ~1 μm2 and porosity of 55%, by a simple and low cost fabrication process. Our results open up a promising approach to achieve solar cells with higher efficiencies by engineering the photo-electrode structure. [ABSTRACT FROM AUTHOR]

Thin film nanocrystalline porous silicon layers have been fabricated from amorphous silicon films using dc plasma hydrogenation and subsequent annealing at temperatures about 450 °C on silicon substrates. Plasma power densities about 5.5 W/cm2 were found to be suitable for etching of the silicon film and the creation of nanoporous layers. The nanoporous structures show visible luminescence at room temperature as confirmed by photoluminescence spectroscopy. The effects of plasma power and annealing temperature on the grain size and luminescence properties of these layers have been investigated by scanning electron microscopy, transmission electron microscopy, photoluminescence, and cathodoluminescence. It was observed that by lowering the temperature during the hydrogenation step, the diameter of the grains increased, whereas lowering the plasma power density caused the distribution of the porous surface structures to become less widely distributed and the formation of more packed structures. In addition, infrared spectroscopy has been used to investigate the origin of the light emitting behavior. [ABSTRACT FROM AUTHOR]

The effects of plasma-enhanced hydrogenation on the crystallization of pure, electron-beam evaporated amorphous silicon (a-Si) at temperatures as low as 300 °C were investigated. Successive steps of hydrogenation in the plasma-enhanced chemical vapor deposition chamber, and in situ annealing in a N2 ambient environment were applied to the a-Si samples over a range of low temperatures and plasma powers. At specific plasma-power densities, nanocrystalline silicon layers with an average grain size of less than 10 nm were formed where their size, distribution, and porosity could be varied by altering the plasma power and hydrogenation temperature. The surface morphology and the nanocrystalline quality of the samples were characterized using scanning electron microscopy, dark-field transmission electron microscopy, and electron diffraction. In addition, by plasma-enhanced oxidation at a temperature of 250 °C, a thin layer of oxide was grown and its physical, structural, and electrical characteristics were investigated. [ABSTRACT FROM AUTHOR]