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In this study, copper ferrite (CuFe 2 O 4 ) nanoparticles were successfully prepared and employed as an efficient catalyst for the synthesis of guanidine derivatives through the addition of anilines to N, N-dicyclohexylcarcodiimide under solvent-free conditions. This magnetically retrievable catalyst was well characterised by Fourier transform infrared spectroscopy, X-ray powder diffraction, transmission electron microscopy and field emission scanning electron microscope-energy dispersive X-ray techniques. The catalyst can be readily recovered from the reaction mixture by the use of an external magnet and reused several times without remarkable loss of its catalytic activity.

In this research work, hierarchical porous carbon foams (CFs) with high surface area and three dimensionally (3D) interconnected macro/meso/microporous structures were prepared through pyrolysis of stabilized poly(acrylonitrile-co-divinylbenzene) P(AN-co-DVB) polyHIPE foams at 900 °C under nitrogen atmosphere. The prepared CFs revealed high surface area (540 m2 g−1), semi-ordered nanoporosity, high electrical conductivity (470 S m−1) and high graphitization degree. Further, HR-TEM observation of CFs revealed the formation of graphitic domains in the structures. The obtained CFs were employed for encapsulation of phase change materials (PCMs) e.g. paraffin (PA) and polyethylene glycol (PEG). The prepared PCMs composites revealed the excellent reversible thermal/chemical stability after frequent 200 heating/cooling cycles. Black CF/PA and CF/PEG composites can be promising structures to be driven either by applying a small voltage (3–3.6 V) with high electric-to thermal efficiency (up to 85%) or by irradiating with sunlight with high photo-to thermal efficiency (up to around 91%).

In this research, Ag+ and Al3+ doped CuInS2 (CIS) nanoparticles were synthesized by a low-cost and non-vacuum hydrothermal method. The CuInS2 nanoparticles were synthesized by the stoichiometric ratio of (1Cu: 1In: 2S) using the hydrothermal method at 180℃ and for 16, 18 and 20 h. Afterward, Ag+ and Al3+ ions were doped with non-stoichiometric composition of (Cu1-xAgx)InS2, Cu(In1-xAlx)S2 (x = 0.1, 0.2, and 0.3), and (Cu1-xAgx)(In1-xAlx)S2 (x = 0.1). The phase evolution, microstructural, and optical properties have also been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), UV–Vis spectroscopy techniques. The XRD results showed that the sample was prepared by the hydrothermal route at 180° C for 20 h was single-phase and no impurity phase was detected. However, some minor impurity phases (CuS and Cu9S5) were detected in the samples were synthesized at 180° C in 16 h and 18 h. The results show that the crystallite size of the synthesized nanoparticles of CIS at 16, 18, and 20 h are 26, 29, and 32 nm, respectively. The lattice parameters for the sample synthesized in 20 h were calculated to be 5.52 A (a) and 11.11 A (c). The FE-SEM micrographs showed that the pure CIS nanoparticles have flower-shaped morphology and the type and concentration of used dopants affect the morphology of the nanoparticles. The bandgap of single-phase CIS synthesized nanoparticles was 1.5 eV. However, the bandgap of (Cu0.9Ag0.1)InS2 and Cu(In0.9Al0.1)S2 was 1.4 eV and 1.70, respectively. The bandgap of (Cu0.9Ag0.1) (In0.9Al0.1)S2 was 2 eV.

Nanotechnologies have reached maturity and market penetration that require nano‐specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)‐by‐Design (SbD) concepts. This paper provides an overview of the state‐of‐the‐art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re‐thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science‐based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally., This study received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 814425 (RiskGONE) and No 814572 (NanoSolveIT).

A new pattern recognition based structural damage detection method using structural mode-shapes along with natural frequencies is presented in this article. A three span RC bridge is selected to verify the proposed method. To conquer the complexities of finite element simulation of the real structure, SAP2000 is employed for FE modeling and analyzing the structure and thus generating the input parameters for damage assessment process. Having the modal data for the intact and damaged structure, extraction of damage properties becomes a “pattern recognition” or “feature discrimination” problem, while Twin Gaussian Process (TGP) as an advantageous pattern recognition technique is employed to compare the measured mode-shapes and frequencies with their healthy state values and identify the damaged elements. The results of this study shows that the suggested method performs precisely in damage identification of structures having an updated as-built model. Furthermore, it can be concluded that TGP, which is used for damage detection process in this study, is an efficient tool to detect both location and severity of structural damages in single and multiple damage scenarios. The proposed method can be widely used for model updating and damage detection of real structures without any restrictions in modeling.

Various seismotectonic province maps were made in Iran by different researchers having different perspectives long ago. The difference in these perspectives has led to differences among the maps in numbers and forms of the seismotectonic provinces. As a primary hypothesis, seismicity coefficients such as a and b values in the Gutenberg-Richter equation must be separately constant in a seismotectonic province. The main objective of this research is to prepare a seismotectonic province map based on seismicity coefficients. Therefore, the areas containing constant seismicity coefficients are placed in one province after determining the seismicity coefficients in interconnected networks in Iran. As a matter of fact, the province borderlines are determined based on the numerical values of the seismicity coefficients. The seismicity coefficients include values a and b in the Gutenberg-Richter equation, and also other parameters include rate of earthquakes per year (λ), largest (Mmax) and smallest (Mmin) earthquakes in the area, and density of faults and earthquakes. In other words, the borderlines of the seismotectonic provinces are calculated based on the numbers and magnitudes of the earthquakes in specific ranges of location and time. A comprehensive map is developed for the seismotectonic provinces in Iran according to the mentioned parameters as well. Based on this map, the region is divided into eleven major seismotectonic provinces and three subzones. The position of each seismotectonic province demonstrates a good compatibility with the geologic and tectonic situation of the region.

A novel facile route was proposed for low-temperature stabilization of polyacrylonitrile (PAN)-based polyHIPE polymers to prepare high surface area graphitic carbon foam (CF) under mild carbonization conditions. In this respect, poly(acrylonitrile-co-divinylbenzene) foams with a distinctive microstructure of polyHIPE foams were coated by a non-graphitizable resin to eliminate the complicated and high-temperature stabilization process before pyrolysis. The prepared nanoporous CFs were characterized by different techniques including nitrogen sorption analysis, Raman spectroscopy, scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HR-TEM). Experimental results revealed that the proposed strategy successfully preserved the foam framework and porosity shape after pyrolysis at 900 °C. The prepared CFs exhibited a high BET specific surface area and a pore volume of 879 m2 g−1 and 0.59 cm3 g−1, respectively. The Raman spectroscopy and HR-TEM results confirmed the successful stabilization and the formation of graphitic domains in the CFs. The obtained CFs when utilized as an anode of Li-ion batteries (LIBs), and showed improved rate capabilities compared to a commercial graphite anode and stable cycle performance up to several hundred cycles. The results revealed the potential applications of the prepared CFs in the batteries specialized for high-power devices.

Hollow Microspheres of SiO 2 -TiO 2 photocatalysts whose walls are made up of mesoporous cellular foams were synthesized with the aid of hexane as a swelling agent and P123 as a pore template by an emulsion templating method. Pore structure of materials and crystal phase of titanium oxide was tailored by hydrothermal and calcination temperature during synthesis of samples. The samples were characterized with field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), N 2 adsorption–desorption experiments, X-ray photoelectron spectroscopy (XPS) and X ray diffraction (XRD) techniques. The effect of pore structure and titania phase on photoactivity were evaluated by methylene blue (MB) degradation test under UV light as well. Results showed that hydrothermal temperature during synthesis process has a significant effect on pore and window sizes of mesostructured cellular foam. Interestingly, for the sample hydrothermally treated at higher temperature (130 °C), anatase to rutile transformation was avoided after calcination treatment as high as 800 °C. The highest photocatalytic activity was detected from the sample hydrothermally treated at 130 °C and calcined at 800 °C for which the highest degree of crystallinity and anatase phase as well as enhanced pore connectivity was obtained.

Hollow mesoporous silica nanoparticles have emerged as attractive drug delivery carriers. In this work, we report successful synthesis of hollow mesoporous silica nanoparticles (HMSNs) using poly tert-butyl acrylate (PtBA) nanospheres as hard templates and CTAB as structure directing agent for loading sulfasalazine into its porous structure. The samples were synthesized using PtBA; sodium dodecyl sulfate (SDS) - in an aqueous solution of CTAB and tetraethylorthosilicate (TEOS) as the inorganic precursor. Two different methods were utilized to remove organic phases including calcination, and acidic/basic ethanolic solvent extraction approach. For the latter, microstructural studies using SEM and N 2 porosimetery revealed the formation of highly uniform mono-dispersed particles of sphere morphology (~ 130 nm) with the high specific surface area (1501 m 2 /g) and mean pore size of ~ 2.6 nm. However, rather deformed and aggregated sphere-like particles were obtained for the calcined samples. TEM examinations also confirmed the formation of 20–30 nm thick walls for the prepared HMSNs particles. Further, HMSN samples treated by solvent extraction method were functionalized by 3-aminopropyl triethoxysilane (APTS) compound for drug delivery. DTA/TG analysis showed that the total amount of loaded sulfasalazine drug was 5.1 wt%.

Ca 1-X La X Fe 12 O 19 (x = 0 and 0.4) polycrystalline powders were synthesized by the solution combustion route using glycine as a fuel and nitrates as oxidizers. After the combustion reaction, the prepared powders were calcined at 1100 °C and 1200 °C in a static air atmosphere for 1 h. The thermo gravimetric (TG) study was carried out to understand the ignition temperature. The structural and morphological studies of the prepared hexaferrite powders were carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Magnetic properties of these samples were also measured by vibrating sample magnetometer (VSM). The XRD results of the samples which consisted of La as dopant and calcined at 1200 °C for 1 h, indicated the formation of calcium hexaferrite and also α-Fe 2 O 3 . However, the XRD results showed that CaFe 4 O 7 and α-Fe 2 O 3 phases were formed in the sample with the same condition but without using any dopant. The micrograph of SEM showed that the calcium hexaferrite particles were regular hexagonal platelets with the size range of 1–2 μm. Maximum magnetization (M Max ), remanent magnetization (M r ), and coercivity (H c ) were measured from the hysteresis loops. Low values of coercive field (23.52 kA m −1 ) and maximum magnetization (58.75 Am 2 kg −1 ) were originated from calcium hexaferrite particle which calcined at the temperature of 1200 °C for 1 h.

In this study, mesoporous tungsten oxide nanostructure was successfully synthesized using inexpensive peroxotungstic acid as a tungsten precursor, and pluronic P123 blockcopolymer as a template. Various techniques such as differential thermal analysis, thermogravimetric analysis, Fourier transformed infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, nitrogen adsorption/desorption analysis, and UV–Vis spectroscopy were utilized to characterize the prepared tungsten oxide. Nitrogen adsorption/desorption analysis demonstrated the formation of mesoporous structure with the specific surface area of 67 m2/g and pore size of ~ 6 nm after calcination at 500 oC for 1 h. Microstuctural investigation by field emission scanning electron microscopy images revealed the existence of spherical morphology for the prepared mesoporous tungsten oxide powder. X-ray diffraction analysis confirmed the formation of orthorhombic crystalline structure. In addition, the calculated energy band gap of the calcined product was found to be 2.60 eV. Further, photocatalytic activity of the synthesized crystalline powder was verified for Rhodamine B degradation, giving rise to 79% dye removal from aqueous solution with 6 mg/L concentration under ultraviolet irradiation.

La-substituted hexagonal calcium ferrite, Ca1−XLaXFe12O19 (x varies from 0 to 0.6 with the step of 0.2), was synthesized by applying co-precipitation method, in which the molar ratio of Fe3+/(Ca2++La2+) was 11. The ferrite precursors were prepared from aqueous solution of calcium nitrate, ferric nitrate and lanthanum nitrate by co-precipitation of calcium, iron and lanthanum ions by using an aqueous base of sodium hydroxide (1.5 M) at the pH of 14 and at room temperature. These precursors were calcinated with different amount of La at different temperature of 700, 1100 and 1200 °C for constant calcination time of 1 h in a static air atmosphere. Some tests such as simultaneous thermal analysis (STA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM) were carried out to investigate the thermal behavior, crystallographic properties, morphology and magnetic properties of the precursor powders which were calcinated at different temperatures. The powder XRD patterns of samples which consisted of La as dopant and were calcinated at 1200 °C for 1 h, indicates the formation of calcium hexaferrite and also α-Fe2O3 besides Magnetoplumbite-phase (M-phase). However, the results showed that CaFe4O7 and α-Fe2O3 phases were formed in the sample with the same condition but without using any dopant. The results of SEM showed that the calcium hexaferrite particle were regular hexagonal platelets with the size range of 1–2 µm. The magnetic properties such as maximum magnetization (MMax), remanent magnetization (Mr) and coercivity (Hc) were measured from the hysteresis loops. Low values of coercive field (16.3 kA m−1) and maximum magnetization (50.6 A m2 kg−1) were obtained from calcium hexaferrite particle in optimum amount of La (X=0.4) which calcinated at the temperature of 1200 °C.

The challenge of developing highly graphitized regions in mesoporous carbon powders via non-catalytic approach has been the focus of many researchers worldwide without much noticeable achievements. Here, in this work, for the first time, we report the profound effect of the addition of water soluble planar polyaromatic hydrocarbon molecules (PAH) on the development of graphene structure within amorphous carbon matrix, as confirmed by our detailed analytical experiments. The formation of rather long-range ordered graphene layers for the prepared samples is believed to be mainly governed by the initial spatial planar alignments of benzene rings of phenolic resin monomers and those of PAHs molecules. Amongst the synthesized samples, the highest specific surface area (∼620 m2/g) and electrical conductivity (∼6.25 S/cm) were obtained for Emodin added sample as a non-metallic graphitizing agent. Such rather high specific surface areas and electrical conductivity potentially promises wide range of interesting applications for mesoporous carbon materials.

We have investigated the microstructure and the magnetic properties of as-cast and flash annealed (4 s at 420 °C–560 °C) Fe84.3Si4B8P3Cu0.7 melt-spun ribbons. The scanning electron microscopy-electron backscattered diffraction (SEM-EBSD) analyses proved the existence of crystalline layer with the thickness of 1 μm in the as-cast state on both the wheel-contacted and the free surfaces of ribbons. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) patterns showed that the crystalline surfaces were textured. Moreover, the microstructure, composition and phase evolution of surface crystallization were studied using TEM and 3DAP which the spherulitic microstructure on the surface was demonstrated. Flash annealing above 420 °C led to a nanocrystalline microstructure of containing 10–15 nm α-Fe (Si) crystallites embedded in a residual amorphous matrix containing Fe, Si, B and P. Three-dimensional atom probe (3DAP) and high resolution transmission electron microscopy (HRTEM) analysis revealed that boron and phosphorous were rejected from α-Fe (Si) phase and enriched in the residual amorphous phase. The nucleation of the nanocrystals occurs heterogeneously from the 3–5 nm α-Fe crystals that were present in the as-cast state. The saturation magnetic induction (Bs) increases from Bs = 1.55 T in the amorphous state to Bs = 1.76 T after the crystallization. The saturation magnetostriction constant, λs, decreased from originally 35 ppm in the as-cast state to about 14 ppm with coercive fields in the range of Hc = 20–30 A/m.

An attempt is made to study the effect of substituting Si and Cu atoms for B in Fe84B16 alloys on the microstructure and magnetic properties of the resulting melt spun compositions (i.e., Fe84B14Si2 and Fe84B12Si3.3Cu0.7). As-spun and annealed samples were characterized by various techniques to investigate their crystallization kinetics and the magnetic properties of the resulting microstructures. Experiments have revealed that Fe84B12Si3.3Cu0.7 composition exhibits the optimum magnetic properties of MS=1.92 T and HC=11 A/m among the three samples under study.

The effect of phosphorous on the microstructure and magnetic properties of as-spun and flash annealed (389–535 °C for 7 s) Fe85Cu1Si2B8P4 melt spun ribbons were investigated by three-dimensional atom probe (3DAP) and high resolution transmission electron microscopy (HRTEM) techniques. The formation of quasi-amorphous α -Fe clusters of 3–5 nm size in an amorphous matrix were detected by HRTEM, despite the high quenching rate applied by high wheel speed used. Flash annealing of the as-spun ribbons gave rise to the formation of nanocrystalline α -Fe (Si) phase in amorphous matrix containing Fe, Si, B and P elements as detected by 3DAP. Comparing 3DAP analysis of the samples annealed at 445 °C and 535 °C revealed that the concentration of P and B in amorphous matrix were increased for the latter. Further, it was shown that P hardly solidified into nanocrystalline phase and partitioned in amorphous phase alongside B atoms leading to the further stabilization of amorphous matrix as confirmed by 3DAP analysis. The highest magnitude of saturation magnetic induction (Bs~1.85 T) and the lowest coercive field (~10–20 A/m) were obtained for the samples annealed above 445 °C, for which noticeable reduction of saturation magnetostriction ( λ s) were also detected.

The properties of colloidal nanoparticles are the key parameters in the fabrication of inexpensive solar cells based on the solution methods. In this study, Different nanostructures of CuInS2 (CIS) were successfully synthesized by a heating-up facile polyol-based method in which, polyols including diethylene glycol (DEG), ethylene glycol (EG), and glycerol (Gly) were chosen as both the solvent and the reductant. It is found that not only the indium precursor type but also the polyol solvent are greatly effective on the size, morphology and crystal phase of this sulfide ternary composition. Briefly, the heating-up synthesis using In(acac)3 in DEG and Gly media, created nano-sized particles that arranged in a wurtzite crystalline structure. Resulted CIS particles from other indium salts are not suitable for making nanoparticle-based inks, since the micron-sized agglomerated particles are obtained which lack proper dispersion behavior for making inks.

Due to the special properties of electrospun nanofibers such as high surface area and porosity, ease of surface functionalization, low pressure drop, suitable mechanical strength, their application in the fabrication of air purifying filtration media has increased dramatically in the recent years. The release of nanomaterials from electrospun nanofibers and human exposure to these substances is one of the concerns regarding to application of nanofiber media in air purifying applications. The aims of present study were to fabricate and characterize the nanofiber filter media, and to determine the release of nanomaterials from them during their application in a filter test rig for removing potassium chloride (KCl) nanoparticles. Polyacrylonitrile, one of the most commonly used polymers in electrospun nanofiber filter media, was embedded with various nanomaterials including magnesium oxide nanoparticles and single wall carbon nanotube and was converted to nanofiber filter mats via electrospinning process. The air samples were collected at the downstream of prepared nanofiber filter mats using polycarbonate (PC) and mixed cellulose ester (MCE) filters according to NIOSH methods 7404 and 7402. The PC filters were analyzed by FE-SEM microscopy for assessing potential release of nanofibers and MCE filters were analyzed by CytoViva's Hyper Spectral Imaging System coupled with Enhanced Dark Field Microscopy (HIS-EDFM) for assessing the potential release of nanomaterials (SWNTs and MgO NPs) from the electrospun nanofiber filter mats. The findings indicated that electrospun nanofibers and their embedded nanoparticles were rarely detached and released from the filter media during normal filtration process. Therefore, it is possible to obtain a very low release by improving quality of the nanofiber filter media and applying a safe design approach.

Biocompatible hollow porous materials, due to their high void volume and shell porosity, are favorable platforms for efficient drug delivery. In this study, carboxylic group functionalized hollow mesoporous silica nanospheres (HMSNs-COOH) were successfully synthesized in a simple and one-pot co-condensation method using polystyrene nanospheres as a hard template, and carboxyethylsilanetriol as a source of carboxyl groups and reaction catalyzer. The synthesized HMSNs-COOH were studied by characterizing their morphology, nanostructure, specific surface area, particle size distribution and chemical composition using FESEM, HRTEM, SAXRD, N2-sorption, DLS, FTIR and TGA techniques. The large specific surface area measured (973 m2 g−1) for the prepared HMSNs-COOH was found to increase the loading capacity of cisplatin to ∼48%, as an anti-neoplastic agent. Furthermore, release tests performed at three different pH values of 7.4, 6.5 and 5.5 showed a sustained and pH dependent release of the drug from the prepared HMSNs-COOH. The cytotoxicity of the formulated drug was also examined in c26 colon carcinoma cell lines using the MTT assay. We demonstrate that the drug loaded HMSNs-COOH samples have a lower toxicity than the free drug, due to controlled and sustained drug release.

In any seismic hazard assessment a uniform earthquake catalogue is an essential parameter. In this research, an earthquake catalogue of Iran and adjacent areas was studied, using national and international catalogues. The considered region covers a quadrangle limited by 23 to 42°N and 42 to 65°E including Iran and adjacent areas. Earthquake data from the third millennium BC until 2014 were considered in this study. The standardization of the catalogue in terms of magnitude was achieved and new relations were generated to convert all types of magnitude into moment magnitude by using the orthogonal regression technique. Based on the proposed relations, MW can be estimated and considered as a unified magnitude scale.

In this work, for the first time, we report the successful synthesis of three-dimensionally interconnected porous boron nitride foams (BNFs) with a high degree of crystallinity using porous sacrificial polymeric hard templates. Ammonia borane/CTAB solution were infiltrated inside highly porous preforms of poly(styrene-co-divinylbenzene) (PS), poly(acrylonitrile-co-divinylbenzene) (PAN) and poly(ethylhexyl acrylate-co-divinylbenzene) (PEHA) made using a high internal phase emulsion process. These were later subjected to pyrolysis under an ammonia atmosphere at the rather low temperature of 1150 °C for 90 minutes. The obtained products were characterized using X-ray diffraction, Fourier transformed infrared spectroscopy, N2 sorption analysis, scanning electron microscopy, scanning transmission electron microscopy and high resolution transmission electron microscopy (HR-TEM). The synthesized BNFs closely replicated and retained the open-cellular interconnected microstructure of the polymeric templates. The HR-TEM results revealed the formation of highly crystalline BN stack layers in small domains. The prepared BNF using the PS template showed superhydrophobic behavior which was typical for all of the prepared samples, with a water contact angle of ∼144° and a high adsorption capacity of 1800% for used engine oil.

The relationship between the self-potential (SP) produced by a polarised sphere and its depth was studied in a laboratoryexperiment.Thiswascarriedoutbyusingaspheremadeupoftwohemispheresofdifferentmaterials:onecopper andtheotherzinc.Self-potentialsweremeasuredbyplacingthesphereatagivendepthinarectangularglasstank filledwith water.Thesurfaceofthewaterwascoveredbyasheetwith684brasselectrodes.Asensitive,highimpedancedigitalvoltmeter wasusedtomeasurepotentialsfromeachelectrodetoa'base'.WehavemeasuredtheSPresponseofthemetallicbodyandour workshowsthatSPsignalsofseveralmillivoltsaregeneratedduetothesphereplacedwithinwater.ThegriddedSPdatashow aclearanomaly overthesphereat shallow depths,and asthedepthof thesphereincreases,themeasuredSPsignalduetothe sphere decreases. An analytical formula is given to determine the maximum depth of the sphere at which the presence of the anomaly can be detected. Responses from other geometries are examined as well.

Siliceous templates of KIT6 with three dimensional Ia3d symmetry were synthesized hydrothermally using three block copolymer (pluronic P123) as surfactant. The samples were characterized by XRD (X-Ray Diffraction), SAXRD (Small-Angle X-Ray Diffraction), BET (Brunauer–Emmett–Teller), BJH (Barrett–Joyner–Halenda), and TEM (Transmission Electron Microscopy). The template synthesized at 130 °С (KIT130) had a large pore diameter (8 nm) and a considerable pore volume (1.179 cm3 g−1). Since formation of mesoporous MgFe2O4 proved to be impossible using single the step nanocasting method, a combination of co-precipitation and nanocasting were employed. Mesoporous magnesium ferrite was synthesized through calcining the filled templates at 900 °С and, after the removal of templates, the samples were characterized by XRD, SAXRD, BET, and VSM (Vibrating Sample Magnetometer). The mesoporous magnesium ferrite showed pore diameters of 3 and 9 nm, a pore volume of 0.3 cm3 g−1, and a high specific surface area of 100.27 m2 g−1. Room temperature magnetization of mesoporous magnesium ferrite showed a superparamagnetic behavior.

Micro/mesoporous boron nitride (BN) nanosheets were synthesized through a simple one-pot procedure using cetyl trimethylammonium bromide (CTAB) and ammonia borane (AB) as a structure-directing agent and a BN precursor, respectively. The pyrolysis of the CTAB/AB hybrid under an ammonia atmosphere at 1150 °C produced a white BN powder. We investigated the effect of the CTAB/AB weight ratio on the morphology and physical properties of the prepared powders. The obtained products were characterized by using X-ray diffraction techniques, X-ray photoelectron spectroscopy, scanning electron microscopy, scanning transmission electron microscopy, transmission electron microscopy, and N2-sorption analysis. We found that increasing the weight ratio of CTAB/AB changed the morphology of the synthesized materials from densely packed porous structures to two-dimentional micro/mesoporous BN powders. The high surface area of 1401 cm2 g–1 and pore volume of 1.56 cm3 g–1 and micropore volume of 0.41 cm3 g–1 were obtained for a CTAB/AB weight ratio of 10:1. Hydrogen sorption analysis revealed that the obtained powder has a hydrogen-adsorption capacity of approximately 1 wt.-% at 77 K and 100 kPa.

Here, a facile dual templates method for the synthesis of hierarchical porous boron nitride (HPBN) powders is reported. For this purpose, ammonia borane (AB) and polystyrene latex/cetyltrimethyl ammonium bromide (CTAB) were used as BN precursor and inorganic templates, respectively. The as-synthesized material was pyrolyzed at 1150 °C in ammonia atmosphere resulting in the formation of white BN powder. The typical N 2 sorption analysis demonstrated formation of porous BN with presence of macro/meso and micropores. Transmission electron microscope (TEM) observations revealed the existence of rather uniform macropores with 55–60 nm in diameter, as well as wormlike mesopores and micropores extended between macropores walls. X-ray diffraction (XRD) and high resolution TEM (HRTEM) analyses displayed the formation of turbostratic-BN with atomic layer distance of 0.37 nm. HPBN powders showed fast adsorption rate of methylene blue (MB) solution and high adsorption capacity of 263.1 mg g −1 for MB at room temperature.

The crystallization processes that occur in amorphous melt-spun ribbons of nominal composition Fe 80 B 10 Si 8 Nb 1 Cu 1 during preparation and heat treatment affect the soft magnetic properties of this alloy. Fe 80 B 10 Si 8 Nb 1 Cu 1 alloys are prepared by different quenching rates (wheel speeds of 10, 20 and 40 m/s) and their soft magnetic properties are studied. The XRD data reveal that as the wheel speed increases, the fraction of crystallinity and the Fe–Si grain size both decrease. These data also show that the sample prepared by the wheel speed of 10 m/s exhibits α-Fe particles on its free surface. The data for the samples prepared by the wheel speed of 20 and 40 m/s are in good agreement with the HRTEM images. VSM measurements show that these nanostructured samples exhibit coercivity in the range of 3–21 A/m and magnetic saturation in the range of 1.55–1.78 T.

We report a successful synthesis of Mesoporous BN (MBN) powder through a facile one-pot synthesis strategy. In this respect, laboratory made block copolymer, polystyrene-b-poly(ethylene oxide) (PS-b-PEO) was used as structure directing agent and ammonia borane was used as BN precursor, respectively. Various characterization techniques such as X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM) and N2 sorption analysis were used to characterize different properties of the synthesized MBN powder. The formation of turbostratic boron nitride with wormlike pores (20 nm) was confirmed by XRD and TEM results. N2 sorption analysis of the obtained MBN sample exhibited a high specific surface area of 326 m2 g−1 and a pore volume of 0.5 m3 g−1.

Porous boron nitride (BN) powder was prepared through a facile template-free synthesis route through the pyrolysis of controlled polymerized ammonia borane (AB) at 1300 °C. The prepared products were characterized using different techniques such as X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning transmission electron microscopy, transmission electron microscopy and N2 sorption analysis. We investigated the effect of AB polymerization temperature and time on the micropores formation and surface areas of the obtained products. Lower heating temperatures of AB before pyrolysis resulted in higher surface area and micropore volume. The highest surface area was obtained from isothermal heating of AB at 70 °C and 32 h before being subjected to pyrolysis at 1300 °C.

An efficient approach is presented for addressing the problem of finding the optimal facilities location in conjunction with the k-median method. First the region to be investigated is meshed and an incidence graph is constructed to obtain connectivity properties of meshes. Then shortest route trees (SRTs) are rooted from nodes of the generated graph. Subsequently, in order to divide the nodes of graph or the studied region into optimal k subregions, k-median approach is utilized. The weights of the nodes are considered as the risk factors such as population, seismic and topographic conditions for locating facilities in the high-risk zones to better facilitation. For finding the optimal facility locations, a recently developed meta-heuristic algorithm that is called Colliding Bodies Optimization (CBO) is used. The performance of the proposed method is investigated through different alternatives for minimizing the cost of the weighted k-median problem. As a case study, the Mazandaran province in Iran is considered and the above graph-metaheuristic approach is utilized for locating the facilities.

In this research work, a low-cost commercial melamine derived porous carbon foam (CF) was used as a support for three different organic phase change materials (PCMs), including polyethylene glycol (PEG), paraffin (PA), and palmitic acid (PAA). Structural and thermal properties of the novel PCMs composites were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, ultraviolet–visible diffused reflectance spectroscopy, Thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analysis. The obtained CF/PEG, CF/PA, and CF/PAA composites displayed a considerable latent thermal storage capacity of 145.7, 124 and 198.2 J g−1, respectively. The prepared CF/PA showed a better cycle ability than other composites after 200 frequent heating/cooling cycles. The CF/PA composite was effectively integrated with electrical heaters in the test room and led to energy peak load shifting and temperature fluctuation prevention. The black color of the CF/PA composite caused a significant increase in light absorbance and thereby the high light-to-thermal energy conversion efficiency (95%). In addition to high light absorbance, the obtained CF/PA composite could provide domestic hot water (DHW) for a building with an efficiency of 88.1%.

A one-step hydrothermal synthesis process was developed to prepare ordered mesoporous titania–silica materials by using TEOS and TTIP as silica and titania sources, respectively, as well as P123 as a structure-directing agent in acidic conditions. The synthesized materials were hydrothermally treated at various temperatures (70, 100 and 130 °C) and subsequently calcined at 600, 800 and 1000 °C. Small-angle X-ray scattering (SAXS), Field Emission Scanning Electron Microscopy (FESEM), Wide angle X-ray diffraction (WAXRD), Fourier transformed infrared spectroscopy (FTIR) and N 2 adsorption–desorption experiments have been used to characterize the mesoporous materials, which were subsequently evaluated in terms of photocatalytic efficiency. The results show that hydrothermal and calcination temperatures can change surface area, phase composition as well as degree of crystallinity dramatically resulting in varying photocatalytic performance. Although higher hydrothermal and calcination temperatures will result in lower surface area, a higher degree of crystallinity can be achieved which lead to improved photocatalytic properties. Very high calcination temperatures (1000 °C) sharply reduce surface areas in the systems resulting in inhibiting photocatalytic efficiency.

Superparamagnetic, cubic single phase, ordered mesoporous copper ferrite is synthesized through confinement in nanocages of mesoporous silica. The heat generated during the reaction is conserved in the silica template pore channels, which allows the formation of copper ferrite at a relatively low processing temperature. The Jahn–Teller distortion is suppressed due to the effect of nanoconfinement and thus the high temperature phase of cubic copper ferrite is stabilized at room temperature. The particle size obtained from TEM, the crystallite size calculated from XRD and the magnetic domain size estimated from magnetization measurements are all in good agreement, manifesting the significant role of the confinement in the growth and fabrication of crystalline, single magnetic domain, nanoparticles with superparamagnetic behavior at room temperature.

In the work presented here, the soft magnetic properties of Fe 1− x P x ( x =0.36, 0.7, 1.1 at%) rolled sheet alloys were investigated. In this respect, the as-rolled sheets were subjected to a two steps annealing processes; the first one between 800 and 1000 °C for 1 h referred as first stage annealing and the second one at lower temperatures (500 and 600 °C) for 30 min, referred as second step annealing. BH tracer measurements at 50 Hz showed that for all of the phosphorous containing alloys, in general, the magnitude of coercivity decreased by applying these two annealing steps compared to those of as-rolled samples. For all of the studied samples, the B 50 values measured at 50 Hz were in the range of 1.6–1.7 tesla (T). Samples having highest amount of phosphorous (1.1 at%) exhibited lower eddy current loss compared to the rest of the specimens due to the increased electrical resistivity. Besides, microstructural studies revealed that the prepared samples were free from Fe 3 P phase precipitation and the average grain size increased (~three times) with increasing the phosphorous content giving rise to the decrease of hysteresis losses. Further, amongst the whole prepared samples, the alloy containing 1.1 at% P showed the lowest hysteresis loss (6.99 W/kg), eddy current loss (9.25 W/kg) as well as the highest magnetic induction (1.7 T) at 5000 A/M ( B 50 ).

A series of ordered mesoporous single phase Cu1-xZnxFe2O4 spinel ferrites, with x ranging from 0.00 to 0.75 with a step increment of 0.25, are prepared by a novel nanocasting route with the aid of ...

The motion of a point is specified completely through six components, three translational and three rotational. Three rotational components of ground motion are classified to two rocking components and one torsional component. The transitional components of ground motion are easily measurable by standard techniques, whereas the rotational components are not directly accessible. In this study, the rotational component of production technique was described, and the influences of soil type and the distance from the fault on the rotational component were investigated. The results showed that the effect of the rotational components is more significant in low periods. Also, the value of the normalized response spectra for soft soil is more than stiff soil, but for far-fault earthquake, it is less than near-fault earthquake.

The effect of Zn doping on magnetic properties of mesoporous CuFe2O4 has been investigated. The cation distribution amongst tetrahedral (A) and octahedral (B) sites of the lattice has been calculat ...

The most important factors in an earthquake are the casualties and financial losses, therefore it can help city managers to be ready before the events by a good simulation of what can happen in such disaster and recognizing vulnerable regions and consequently estimation of the amount of casualties and damages. Accordingly, one of the most important steps in developing Gorgan's earthquake scenario was estimation the amount of destruction after the earthquake. Beside the site study, site effects study performs an important role in determining the amount of destruction after earthquakes. Our data for site study condition in Gorgan were: log data available in the offices, field study and geological reports, and soil geotechnical tests done by some special housing projects and urban development organization, used as important information in the Gorgan's earthquake scenario process. Fortunately, bores that we used have an appropriate distribution in the city, in a manner that we could study site conditions in Gorgan by relying on their information. After that we modelled the bore loges information in Pro-Shake, and then we selected and applied an referenced accelerogram which used to calculate shear wave velocity, displacement and acceleration on Earth's surface for output. In comparison of input accelerogram and output accelerogram we can find site amplification factor in a given point. By calculating this ratio in the center of squares with 250*250 meters dimensions, site amplification zoning map in the Gorgan region was provided, which was one of the information layers in developing of Gorgan earthquake scenario.

Recently some nanocrystalline soft magnetic materials containing nanosized α-Fe grains have been obtained by crystallization of amorphous melt-spun ribbons. These structures are nanocomposites in which nanosized grains are distributed within an amorphous matrix. The soft magnetic ribbons composed of Fe80B10Si8Nb1Cu1 alloy were prepared by melt spinning method with different quenching rates (wheel speed of 10, 20 and 40 m/s). The XRD results exhibit an increase in the copper wheel speed (quenching rate) causes the fraction of crystallinity and grain size to decrease. The grain size varies in the range of 20 to 200 nm that is in good agreement with TEM results. The VSM results show that these nanostructured samples exhibit coercivity in the range of 10 to 30 A/m and magnetic saturation in the range of 1.5 to 1.7 T.

Self-potential anomalies observed over sulfide ore bodies can be closely associated with electrochemical reactions and the ohmic potential drop within the rocks. Self-potential surveys based on laboratory measurements of electrochemical potentials allow us either to measure the amplitude of the anomalies generated by this mechanism or to determine the model parameters. In order to achieve these goals, two sheets of zinc and copper were joined together to simulate sheet-like ore bodies. Self-potential surveys were conducted over 684 electrodes with the purpose of revealing the influence of various angles of the sheet. In a laboratory experiment, four different inclinations were chosen to perform the forward modelling. The last part of this paper involves the inversion of measured data to recover the distribution of generated self-potential signals. The inversion results show a satisfactory agreement with the laboratory measured data. Finding the geometry of the buried source from the shape of the SP respon...

An attempt has been made to study the effect of sol ageing time and temperature on the mesostructural order, thermal stability, and adsorption–desorption behavior of mesoporous titania prepared by the templating method. Two different sets of sols were prepared: the first group were aged for 0.0, 1, 2, 3, 4, 5, 6, or 19 h at room temperature and the second set were aged at 50 °C for 0.0, 1, 4, 8, or 14 days. The gels obtained were subsequently subjected to humidity treatment and drying followed by calcination at 350, 400, 450, or 500 °C for 2 h. Dynamic light scattering (DLS), small-angle X-ray diffraction, wide-angle X-ray diffraction, Raman spectroscopy, and high-resolution transmission microscopy, among other techniques, were used to characterize the samples. DLS studies revealed the critical effect of ageing conditions (time and temperature) on micellar aggregation and arrangement of the prepared sols. Whereas room temperature sol ageing for different times (0.0–19 h) resulted in the formation of large aggregates/clusters, smaller micellar aggregates were formed by ageing at 50 °C. A fully ordered hexagonal mesostructure (p6 mm) was obtained when calcined samples were prepared from sols aged for 14 days. However, for calcined samples prepared from unaged sol a wormlike structure was observed. Moreover, for sols aged at 50 °C, increasing the ageing period improved the mesostructural order, which led to higher specific surface areas, pore volumes, mesoporosity, and thermal stability. Finally, it was shown that the size and size distribution of the oxo-clusters/aggregates formed in the prepared sols and their subsequent complementary condensation during drying had a substantial effect on the final mesostructural order of the calcined samples.

In this study, the planar flow casting (PFC) technique for producing wide amorphous ribbons of Fe71Si13.5B9Nb3Cu1Al1.5Ge1 alloy is investigated. Various ribbons of the mentioned alloy were produced through applying different values of wheel speed and ejection pressure. In addition, effects of wheel speed (13, 23, and 33 m/s) on the structure, degree of amorphicity, and surface quality of the ribbons were examined. The results showed that the trends of thickness variation with increasing wheel speed and ejection pressure for Fe71Si13.5B9Nb3Cu1Al1.5Ge1 ribbons are in good agreement with what the Bernoulli equation in fluid dynamics predicts for the PFC process. Further, based on x-ray diffraction and differential scanning calorimeter results, it was shown that the degree of amorphicity increases by increasing the wheel speed. Besides, surface roughness measurements and scanning electron microscope micrographs of the ribbons revealed that the surface quality of the prepared ribbons improved by increasing the wheel speed.

During an earthquake loading, the ground response parameters are significantly affected by the soil thickness, stiffness, type, and geological condition. There are various techniques for the determination of characteristics of soil which can be used for site effect assessment. Previewing past studies indicated that earthquake records provide a very applicable and useful tool to estimating the characteristics of soil. In this study, the system identification method based on particle swarm optimization algorithm was described. Then this technique is utilized to estimate the characteristics of soil profile of the Babol accelerograph station by using ground shaking data recorded during the recent Babol earthquakes of May 28, 2004 and January 11, 2012. Moreover, for determining the accuracy of the present technique, the obtained results were compared with the downhole test, microtremor measurement, and numerical site response modeling. The obtained results reveal that the present system identification method successfully estimated the soil properties.

Mesoporous TiO2 has been synthesized by the sol–gel method, using a nonionic triblock copolymer P123 as surfactant template under acidic conditions. The as-prepared samples were characterized by thermogravimetry–differential thermal analysis (TG–DTA), nitrogen absorption–desorption (BET), field emission scanning electron microscopy, and transmission electron microscopy. The photocatalytic activity of the mesoporous TiO2 was evaluated by degradation of methylene blue under high-intensity UV light irradiation; the amount of methylene blue was measured by UV–visible spectroscopy. TG–DTA analysis revealed that the surfactant had been removed partly in as-synthesized samples. BET analysis proved that all the samples retained mesoporosity with a narrow pore-size distribution (4.5–6.3 nm) and high surface area (103–200 m2/g). All calcined mesoporous TiO2 had high photocatalytic activity in the photodegradation of methylene blue.

In this work successful synthesis of multiwall carbon nanotube (CNT) using solution combustion and chemical vapor deposition (CVD) methods are reported. Ceramic nanocomposite samples of (Al 2− x Fe x O 3 )–( y )ZrO 2 formula with x = 0.017, 0.034 and 0.17 and y = 0.15 were initially prepared. These were then subjected to CVD process during which the in situ reduction of iron oxide to metallic iron (Fe/Fe 3 C) phase/s provided the necessary catalyst for the CNT formation. The formation of long flexible filaments with a smooth and regular surface bridging between alumina–zirconia (AZ) grains could be detected. The diameters of the formed filaments were in the range of ∼70 to ∼320 nm and length of the order of some tens of micrometers. However, transmission electron microscope (TEM) examinations also revealed the existence of small amounts of Bamboo-like carbon along with more or less straight CNTs. This could be related to the lack of strong interactions between the metallic iron phase/s and the nanocomposite support.

Ordered TiO 2 –SiO 2 mesoporous materials with BJH pore diameters in the range from 12 to 15 nm were synthesized by a one-step hydrothermal synthesis method. In this route, tetraethoxysilane (TEOS) and titanium tetraisopropoxide (TTIP) in a low pH solution were used as SiO 2 and TiO 2 precursor, respectively with P123 as a template and hexane as a micelle expander in the presence of NH 4 F. In this work, we show the effect of different hydrothermal temperatures (70 °C and 130 °C) on pore structure and photocatalytic efficiency of the materials prepared. The synthesized materials were characterized by small-angle X-ray scattering (SAXS), N 2 adsorption–desorption experiments, X ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). The method could produce ordered mesoporous structure with uniform pore size of 12–15 nm and high specific surface areas S BET up to 431 m 2 /g. The photocatalytic activity of the samples was evaluated by degradation of MB under UV light irradiation and results showed these mesostructure materials have much higher photocatalytic efficiency in comparison with commercial P25 titania. The results also show that for materials synthesized using higher hydrothermal temperature (130 °C) resulting in increased in photocatalytic activity due to higher formation of anatase phase and more open channels by comparison with lower hydrothermal treatment (70 °C).

TiO2–SiO2 mesoporous materials were synthesised by deposition of TiO2 nanoparticles prepared by the sol–gel method on to the internal pore surface of wormhole-like mesoporous silica. In this work we synthesised wormhole-like mesoporous silica of different surface area by changing the hydrothermal temperature (70, 100, or 130 °C). Subsequent to this, titania solution was deposited on to the inner surface of the pores and this was followed by calcination at different temperatures (400, 600, or 800 °C). The effect of different hydrothermal and calcination temperature on the photocatalytic properties was evaluated. The samples were characterized by N2-sorption, X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy. The effect of different hydrothermal and calcination temperatures on the photocatalytic properties was evaluated by measuring the degradation of methylene blue in aqueous solution under UV light irradiation (mercury lamp, 125 W). The results indicated that appropriate surface area and degree of crystallinity are two important factors for obtaining high photocatalytic efficiency. Samples prepared at a hydrothermal temperature of 100 °C and calcined at 800 °C had the best photocatalytic performance, because of the highest surface area and high crystallinity.

A glass with the composition of 35Na 2 O–24Fe 2 O 3 –20B 2 O 3 –20SiO 2 –1ZnO (mol%) was melted, quenched, using a twin roller technique, and subsequently heat treated in the range 485–750 °C for 1–2 h. This led to the crystallization of magnetite as the sole or the major crystalline phase. Heat treatment at lower temperatures resulted in the crystallization of magnetite crystals 7–20 nm in diameter, whereas heat treatment at higher temperatures produced higher quantities of magnetite and much larger crystals. The room temperature magnetization and coercive force values were in the range of 6–57 emu g − 1 and 0–120 Oe, respectively for the heat treated glasses.