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The iron (III) Schiff base complex was immobilized on magnetic silica as well as mesoporous silica substrates and characterized by XRD, TEM, FT-IR, AAS, VSM techniques, and in the case of mesoporous silica, it was also identified with N2 adsorption/desorption and TGA methods. These materials were applied for oxidation of benzyl alcohols and sulfides with hydrogen peroxide as a green oxidant. The effect of catalyst structures was studied in the mentioned reactions. The results showed that using of mesoporous silica in the oxidation of sulfides and benzyl alcohols with hydrogen peroxide in the optimal reaction conditions provided a higher catalytic yield in the same or even less reaction time. The higher catalytic performance of the mesoporous substrate based on the identifications (carried out by N2 adsorption/desorption technique) can be attributed to the higher surface area of this substrate and the stronger connection of the Schiff base complex of iron (III) to the mesoporous silica (according to leaching test). [ABSTRACT FROM AUTHOR]

Separation and mapping of alteration zones is of special importance in the exploration of porphyry copper types. In order to highlight these alteration zones, remote sensing techniques have been applied. Zafarghand region is located in the southeast of Ardestan and northeast of Isfahan. Based on the division of geological structural zones, it is located in the Central Iran zone and also in the middle part of Urmia-Dokhtar magmatic volcanic arc. In this area, there are different alteration halos, including phyllic, potassic, propylitic, argillic, and slightly siliceous. In this study, argillic, phyllic, propylitic, and clay alterations have been identified using ASTER sensor images. Moreover, LANDSAT 8 images have been employed to identify clay and iron oxide alterations. In this regard, after performing the necessary pre-processing, methods of False Color Combination (FCC), Band Ratio (BR), Least Squares-Fit (LS-Fit), Matched Filtering (MF), and Principal Combination Analysis (PCA) were applied to reveal the zones containing these alterations. Among the applied methods, the LS-Fit and MF in Aster images, as well as the BR method in both images, and the PCA method in Landsat 8 have brought good results. [ABSTRACT FROM AUTHOR]

Flooding and drainage cycles affect the biological and chemical characteristics of the soil in paddy fields and play an important role in cadmium (Cd) availability. In this study, the effect of biochar (B), hematite (H), and their simultaneous application (HB) on pH, Eh, and calcium chloride extractable Cd was investigated in a Cd-contaminated soil during a flooding and drainage period. Also, the Cd fractionation at the end of the incubation period was studied. The pH value increased during the flooding period and decreased with the beginning of the drainage period. The Eh value decreased from the beginning of the flooding and showed an increasing trend during the drainage period. Calcium chloride extractable Cd decreased during the flooding period, while at the beginning of the drainage increased with a slight slope and followed a decreasing trend up to the end of the drainage period. Cd concentration reduced at the end of the flooding period in the B, H and HB treatments compared to the control by 16.8%, 20.5%, and 25.7%, respectively. Also, the reduction in Cd concentration compared to the control treatment at the end of the drainage period was 18.2, 23.1 and 28.2% respectively. HB treatment reduced the Cd availability by reducing the soluble and exchangeable fractions and increasing organic, iron, and manganese oxides fractions. The results indicated that the application of amendments can reduce Cd availability in paddy fields and its uptake by the rice plant. [ABSTRACT FROM AUTHOR]

The widespread use of produced metal oxide nanoparticles has raised major concerns about their impact on human health and aquatic organisms. The aim of the present study was to determine the effects of iron oxide nanoparticles (FeO) and microalgae Spirulina platensis on the gills of gray mullet (Mugil cephalus) in four groups, i.e., first or control (without iron oxide nanoparticles and algae extract), second (15 mg/kg iron oxide nanoparticles), third (300 mg/kg algae extract) and fourth (15 mg/kg iron oxide nanoparticles and 300 mg/kg algae extract) during three periods of 3, 14 and 28 days. For this purpose, 72 specimens of gray mullet were acclimated to the experimental condition and exposed to different concentrations of iron oxide nanoparticles and algae extract in the mentioned groups and time periods. Then the gill tissue of each fish was sampled and the slide tissues were prepared. The gill tissue complications were hyperplasia, hyperemia, secondary lamella shortness, secondary lamella fusion, lamella deformity, epithelial detachment, and lamella clubbing. The fourth group showed more complications in all three time periods, and after that, the second and third groups showed more respectively. The more exposure time caused more tissue complications and the highest number of complications was observed on day 28. Also, algae had no effect on reducing tissue complications in fish, while it caused tissue complications but with less intensity. Based on the results, iron oxide nanoparticles can endanger fish health over time. Therefore, further studies are needed to evaluate its potential toxic effects.

The widespread use of produced metal oxide nanoparticles has raised major concerns about their impact on human health and aquatic organisms. The aim of the present study was to determine the effects of iron oxide nanoparticles (FeO) and microalgae Spirulina platensis on the gills of gray mullet (Mugil cephalus) in four groups, i.e., first or control (without iron oxide nanoparticles and algae extract), second (15 mg/kg iron oxide nanoparticles), third (300 mg/kg algae extract) and fourth (15 mg/kg iron oxide nanoparticles and 300 mg/kg algae extract) during three periods of 3, 14 and 28 days. For this purpose, 72 specimens of gray mullet were acclimated to the experimental condition and exposed to different concentrations of iron oxide nanoparticles and algae extract in the mentioned groups and time periods. Then the gill tissue of each fish was sampled and the slide tissues were prepared. The gill tissue complications were hyperplasia, hyperemia, secondary lamella shortness, secondary lamella fusion, lamella deformity, epithelial detachment, and lamella clubbing. The fourth group showed more complications in all three time periods, and after that, the second and third groups showed more respectively. The more exposure time caused more tissue complications and the highest number of complications was observed on day 28. Also, algae had no effect on reducing tissue complications in fish, while it caused tissue complications but with less intensity. Based on the results, iron oxide nanoparticles can endanger fish health over time. Therefore, further studies are needed to evaluate its potential toxic effects. [ABSTRACT FROM AUTHOR]

Prevention of infection and bioactivity of implantable parts in the body is one of the most important issues investigated in medical research in recent years. In this regard, researchers have conducted many studies in order to increase the bioactivity of implantable parts in the body. Increasing the bioactivity of these parts has been done in different ways, while coating the surface of the parts is considered as one of the best methods in this field. In this research, simultaneous coating of iron oxide nanoparticles (magnetite) along with 45S5 bioactive glass on AISI 316 stainless steel substrate was deposited by electrophoretic method to increase the bioactivity and the possibility of hyperthermic applications. X-ray diffraction analysis confirmed the presence of both iron oxide nanoparticles and bioactive glass. Electron microscope was employed to study the coating surface. Conducting surface investigations by surface roughness and wetting angle measurements, it was shown that the roughness of the coated surface was 49.2±1 gm and the wetting angle of this coating was obtained to be 49°. The results declared that this coating had a surface with medium roughness and hydrophilic properties, which was of great importance for bioactivity performance. Investigating the magnetic properties of the coating, magnetometric evaluation was performed on the synthesized samples. The saturation magnetization and the Hc parameter values of the coating were obtained to be 20.2 emu/g and 89 Gauss, respectively. [ABSTRACT FROM AUTHOR]

Nanopowders/Nanostructures have attracted the attention of engineers and scientists for their tunable properties and extended applications. One of the extended application of nanopowders is nanofluids. Nanofluids are assumed as the most preferred next generation coolants and their stability is essential for their successful implementation. Iron oxide nanoparticles were prepared by the sol-gel method using Ferrous sulphate as precursors. The prepared nanoparticles were characterized by XRD and photo luminescence. Iron oxide nanofluids (0.1 & 0.3 vol%) with ethylene glycol as base fluid were prepared by a two-step method. The nanofluids were tested for dynamic stability (at 1, 3, 6, 12 and 24-hour intervals). The variation in zeta potential with time is analyzed to predict their stability transformations. We observe that 0.3 vol% nanofluid exhibits better dynamic stability characteristics than the less stable 0.1 vol% nanofluid

Thermoset nanocomposites, due to their strength and special physical and mechanical properties compared to metal materials, are widely used in the manufacture of household appliances, electrical appliances, coatings and sports equipment, and sanitary wares. The thermal properties of epoxy nanocomposites depend on the adhesion between the nanoparticles and matrix. Also, designing high quality and efficient epoxy nanocomposites with suitable physical and mechanical properties requires understanding the phenomena that occur during the curing reaction. The reaction of epoxy resin and curing agent as well as the study of curing kinetics play an important role in controlling the deformation of the structure and physical and mechanical properties of the composites. Investigating the dispersion of nanoparticles and selecting the appropriate mixing method can improve the curing reaction or crosslinking of epoxy nanocomposites. It can also prevent the agglomeration of nanoparticles, that affect thermal reactions. Modified iron oxide nanoparticles reduce the reaction activation energy and the curing time. Reaction time and temperature are two important factors for evaluating chemical curing reactions. Modeling analysis of curing kinetics of epoxy nanocomposites is a solution to overcome the problems of thermal reactions that occur during the curing reactions. In this paper, the curing kinetics modeling of epoxy nanocomposites and the effect of adding modified and unmodified iron oxide nanoparticles on the amount of activation energy, curing index, and rheological, mechanical and thermal properties are introduced.

Heavy metals are among the environmental pollutants that human exposure to some of them through water and food can cause chronic and dangerous poisoning. The problem of poisoning drinking water to arsenic is a pervasive problem and has been seen in almost all countries, whether developed or developing, which endangered the lives of many people. In the present study, the removal of arsenic from water using iron / N-isopropyl acrylamide / chitosan nano-adsorbent was studied and evaluated. In this research, a magnetic nanoparticle was used to absorb arsenic, which is an innovative method. In order to increase the absorption capacity, we use polymer grafting operations on the surface of the nanoparticles, which will greatly increase the specific surface of the adsorbent. In fact, by placing polymers on the adsorbent, the combined desire increases. The results show that synthesized nano-adsorbants have the ability to absorb arsenic at different concentrations. But its concentration varies in different concentrations. Langmuir, Freundlich, Tamkin and Dobbin Radhushev isotherms were fitted with arsenic adsorption at 45 °C, pH = 7.5 at different concentrations. And the results show that a high (R = 0.995) R2 value for Langmuir model confirms that this model is suitable for fitting experimental data. The percentage of arsenic removal in optimal conditions at pH= 7.5, the amount of adsorbent 10 mg, contact time 60 min, temperature 45 °C and concentration of 10 μg/ml was 82.2%.

Background: Increase in the number of peoples with cancer attract many researchers in the field of medical science to find a safe approach to treat it. The application of nanotechnology in this field is very promising, and has led to the design of nanosystems with the ability of simultaneous diagnose and therapy. Based on this, the aim of this project was the synthesis a system with functionality in multimodal diagnosis and therapy. Methods: Here, iron oxide nanoparticles were synthesized through thermal decomposition method, and were covered by Au during five irritations using Lyon's method. Finally, cyclodextrins were attached, and then polymerized on the system. The successful preparation of the system was evaluated using different characterization tests. Findings: Results showed the prosperous preparation of iron oxide nanoparticles with 15 nm mean diameter which was coated with a gold cover that increased the size to 35 nm. Moreover, the presence of cyclodextrin on the surface of system was confirmed by analytical characterization tests. Conclusion: The nanosystem introduced in this project, due to the presence of iron oxide and Au nanoparticles, has the ability to be used in two diagnostic approaches, magnetic resonance imaging (MRI) and computed tomography (CT) scan. Moreover, the presence of cyclodextrin and iron oxide in its structure allows it to be used as a hydrophobic drug delivery system, as well as in photothermal therapy and hyperthermia.

مقدمه: در سال‌های اخیر، استفاده از نانوذرات در تشخیص، تحویل دارو و درمان به دلیل کوچک بودن این ذرات و افزایش نسبت سطح به حجم بسیار مورد توجه قرار گرفته است. مهم‌ترین مشکل زمان درمان سرطان به وسیله‌ی شیمی‌درمانی، عدم دسترسی به قسمت‌های مرکزی توده به علت خون‌رسانی کمتر آن است. هدف از انجام این پژوهش، بررسی میزان سمیت نانوذره‌ی اکسید آهن با پوشش پلی‌دوپامین و بدون پوشش پلی‌دوپامین بر روی سلول‌های سرطانی ملانوما B16-F10 بود. روش‌ها: ابتدا، نانوذره‌ی اکسید آهن به روش هم‌رسوبی ساخته و به وسیله‌ی دوپامین پوشش‌دار گردید. سپس، با استفاده از روش MTT، اثر سيتوتوکسيسيته‌ی این نانوذره‌ی پوشش‌دار و بدون پوشش بر روی رده‌ی حیوانی B16-F10 مورد مطالعه قرار گرفت. یافته‌ها: استفاده از نانوذره‌ی اکسید آهن بدون پوشش بر روی رده‌ی B16-F10 در غلظت 450 میکروگرم/میلی‌لیتر و در بازه‌ی زمانی 72 ساعت سمیت نشان داد و در خصوص نانوذره با پوشش، در هیچ یک از غلظت‌ها و در هیچ یک از دو بازه‌ی زمانی 48 و 72 ساعت، سمیت قابل توجهی وجود نداشت. نتیجه‌گیری: خاصیت سمیت سلولی نانوذره‌ی بدون پوشش در مقایسه با نانوذره‌‌ی با پوشش، به طور معنی‌داری بیشتر بود. با استفاده از پوشش، می‌توان سمیت نانوذره‌ی اکسید آهن را کمتر کرد و از آن برای باند کردن هدایت دارو و همچنین، به عنوان یک ماده‌ی کنتراست در تصویربرداری رزنانس مغناطیسی (Magnetic resonance imaging یا MRI) استفاده نمود

To study the effects of biofertilizers and foliar application of iron oxide nanoparticles on grain yield and some physiological characteristics of black cumin (Nigella sativa L.), an experiment was carried out as factorial in randomized complete block design with three replications at the growing season of 2017, in Agricultural College of Shahrood University of Technology. Treatments consisted of foliar application of iron oxide na.noparticles at three levels (control. 1.5 and 3 g/L water) as the first factor and biofertilizers at five levels (mycorrhizal fungi Glomus intraradices and Glomus mosseae and two types of growth promoting rhizoba.cteria. including Azospirillum and Azotobacter solution with control) as the second factor. Results showed that the highest grain yield was obtained from inoculation with mycorrhizal Argus, Glomus intraradices. The interaction of foliar application of iron oxide nanoparticles and biofertilizers had a. significant effect on antioxidant enzyme activities such as catalase, ascorbat peroxidase and polyphenol oxidase as well as total, "a" and "b" chlorophylls. The highest activity of catalase, ascorbat peroxidase and polyphenol oxidase enzymes were in 3 g/L water Iron oxide nanoparticles treatment of and non-use of biofertilizers. The highest amount of chlorophyll "a" was obtained from 3 g/L water treatment, with Glomus intraradices and chlorophyll "b" from the combination of two concentrations of iron nano oxide with two mycorrhizal fungi. It seems that among the treatments studied, Glomus intraradices had the highest effect on grain yield of the black cumin and application of 3 g iron nano oxide /L of water was highly effective in the photosynthetic pigmentation increasing and antioxidant enzymes activity. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: Stroke is the second leading cause of mortality in the worldwide. After a stroke, many neurons in the ischemic penumbra will undergo apoptosis. The aim of this study was investigation of effects of iron oxide nanoparticles and magnetic field on apoptosis reduction after ischemic reperfusion in rat model. METHODS: In this experimental study, 50 male Wistar rats weighing 220-250g were randomly divided into five groups of 10 rats each: including control, sham (ischemic reperfusion model), ischemic reperfusion + iron oxide nanoparticles (10mg/kg), ischemic reperfusion +magnetic field (1 Tesla, 20 min in 4 days), and ischemic reperfusion + iron oxide nanoparticles and magnetic field groups. Injections were performed intraperitoneally. After Four days, the hippocampi were removed for studying of Apoptosis Induction (by TUNEL technique) and changes in Bax gene expression (by Q-PCR method). FINDINGS: After induction of ischemic reperfusion, TUNEL+ cells number treated with iron oxide nanoparticles (7±2) and or the magnetic field (12±2) had significant decrease (p

Introduction and aims: The aim of radiotherapy is delivering lethal dose of radiation to tumor cells while adjacent healthy tissues would have the least amount of irradiation. One way to increase the dose in the tumor cells is using high atomic number nanoparticles as radiation sensitizers in these cells. Materials and Methods: Dextran-coated iron oxide nanoparticles at different concentrations (10, 40 and 80 µg/ml) were incubated with HeLa cell line of cervical cancer for 24 hours and then the cells irradiated with different doses (0, 2, 4, 6 and 8 Gy) of 6 MeV electron and 6 MV photon beams. Survival fraction of the cells was evaluated by MTT assay. Results: The survival fraction in the groups receiving radiation in the absence and presence of iron oxide nanoparticles showed significant differences (p

Background and Objective: Iron oxide nanoparticles have wide applications such as MRI contrast agent and drug delivery. Nevertheless, their effects on human health have not been fully investigated yet. After cellulose, chitin is one of the most abundant organic materials in nature which is widely used in food industry, cosmetics, agriculture, medicine and the environment. This study was done to evaluate the effect of iron oxide nanoparticles coated with chitosan on renal functional indeces in rat. Methods: In this experimental study, 60 adult female Wistar rats were allocated into 10 equal groups. Concentrations of 50, 100 and 150 mg/kg/bw from chitosan, iron oxide nanoparticles and chitosan coated nanoparticles were intraperitoneally injected into 9 groups and animals in control group were received normal saline. Blood samples were collected directly from the rat heart in the days 15 and 30 post after injection and renal functional indeces including urea, creatinine, uric acid, sodium, potassium and total protein were measured. Results: There were no significant differences in the level of urea, creatinine, uric acid, sodium, potassium and total protein in the groups whom received chitosan-coated iron oxide nanoparticles compared to control. There was no mortality during the study time. Conclusion: Short-term using of iron oxide nanoparticles coated with chitosan does not create any toxicity in the rat kidney.

Iron oxide nanoparticles were synthesized for the first time using electrical arc discharge between a pair of highly pure titanium electrode without using metallic iron electrodes in iron chloride salt solution. The produced nanoparticles were characterized using various analyses such as X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). XRD and XPS analyses showed formation of α-Fe2O3 phase. Microscopic studies on the obtained samples revealed formation of rice like iron oxide nanostructures at 10 minutes of electrical discharge which changed to semi-spherical shape after calcination at 600 oC for 2 hours. The results of Dynamic Light Scattering (DLS) analysis demonstrated formation of 24 nm particles with almost narrow distribution of 11nm, which are increased in size and distribution width by heat treatment. The obtained results verify the potential ability of this technique to achieve monodispersed iron oxide nanoparticles with narrow distribution in a very short time

Industrial and environmental pollution, excessive iron supplementation and blood transfusion are among the factors that may cause iron toxicity. Therefore, it is necessary to identify the mechanisms influencing or protecting against iron toxicity. The present study aimed to investigate the protective effects of quercetin as an antioxidant on hepatotoxicity induced by iron oxide and nano-iron oxide. Materials and Methods: The study was conducted on 30 Wistar rats (five groups): A) control group, B) nano-iron oxide, C) iron oxide, D) nano-iron oxide plus quercetin, and E) iron oxide plus quercetin. Nano-iron oxide and iron oxide were administered in daily doses of 20mg/kg, and quercetin in daily doses of 100mg/kg by intraperitoneal injection for 15 days. Correspondingly, the rats were then euthanized and their liver tissue was transferred to the pathology lab in 10% formalin. Samples were examined by conventional histopathological techniques using the Hematoxylin & Eosin, and Perls’ Prussian blue staining methods, and observed under the optical microscope. Results: The findings showed that nano-iron oxide and iron oxide can lead to inflammation in hepatic lobules and portal triads, sinusoidal dilatation, abnormal proliferation of the hepatocytes and Kupffer cells, and some hepatocyte degeneration. Simultaneous quercetin treatment was found to reduce the histopathological effects of metal particles, particularly iron oxide particles. Moreover, samples were tested for signs of bile retention, fibrosis and necrosis, but the results were negative. Conclusion: The present study confirmed the anti-inflammatory and protective effects of quercetin as an herbal antioxidant on hepatotoxicity induced by nano-iron oxide and iron oxide. [ABSTRACT FROM AUTHOR]

Background and Objective: Iron oxide nanoparticles have wide applications such as MRI contrast agent and drug delivery. Nevertheless, their effects on human health have not been fully investigated yet. After cellulose, chitin is one of the most abundant organic materials in nature which is widely used in food industry, cosmetics, agriculture, medicine and the environment. This study was done to evaluate the effect of iron oxide nanoparticles coated with chitosan on renal functional indeces in rat. Methods: In this experimental study, 60 adult female Wistar rats were allocated into 10 equal groups. Concentrations of 50, 100 and 150 mg/kg/bw from chitosan, iron oxide nanoparticles and chitosan coated nanoparticles were intraperitoneally injected into 9 groups and animals in control group were received normal saline. Blood samples were collected directly from the rat heart in the days 15 and 30 post after injection and renal functional indeces including urea, creatinine, uric acid, sodium, potassium and total protein were measured. Results: There were no significant differences in the level of urea, creatinine, uric acid, sodium, potassium and total protein in the groups whom received chitosan-coated iron oxide nanoparticles compared to control. There was no mortality during the study time. Conclusion: Short-term using of iron oxide nanoparticles coated with chitosan does not create any toxicity in the rat kidney. [ABSTRACT FROM AUTHOR]

Kuh- e -Zar gold deposit located 35 km west of Torbat-e-Heydaryeh, (Khorassan e- Razavi province), East of Iran. This deposit is a specularite-rich Iron oxide type (IOCG). This mine is situated within Khaf-Bardascan volcanic plutonic belt. Based on recent exploration along this belt, several IOCG type system plus Kuh-e-Zar deposit are discovered. In the study area, several type of tuff and lava having acid to intermediate composition are identified (upper Eocene). Oligo-Miocene granite, granodiorite, synogranite and monzonite intruded upper Eocene andesite-dacite-rhyolite. Intrusive rocks are meta-aluminous, medium to high-K series I-type. Based on spider diagram, intrusive rocks show enrichment in LILE = K, Th, Rb and depletion in HFSE = Nb, Sr, Ti. Based geochemistry of igneous rock, they formed in continental margin subduction zone. Propylitic (chlorite) alteration is dominated and covers large area. Silicification is restricted only to mineralized zones. Argillic and albitization is found in certain location and cover small areas. The style of mineralization was controlled by the type and geometry of fault zones. Mineralization is found as vein, stockwork and breccias. Hypogene mineral Paragenesis include: specularite-quartz-gold-chlorite ± chalcopyrite ± pyrite ± galena ± barite. Secondary minerals formed due to oxidation are: goethite, limonite, lepidocrucite, Malachite, Azurite, Covelite, Cerucite, hydrocerucite, Pyrolusite and Smitsonite. In a few localities, chalcopyrite and minor pyrite and galena are found. Based on SEM analysis gold is present as electrum. Mineralization appeared in different type such as vein, stockwork and Hydrothermal breccia in strike sleep fault zone which are hidden inside volcano plutonic rocks. The average gold grade is between 3.02 ppm and ore reserve is estimated more than 3 million tons (cut off grade = 0.7 ppm).