mojgan zendehdel

In this study, Fe3O4 nanoparticles and magnetic nanocomposite of NaP zeolite@Fe3O4 with different ratio were prepared, then in the second step functionalized with 2-aminopyridine as a basic group. All samples were characterized by Fourier transfer infrared (FT-IR), X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy dispersive X-Ray analysis (EDX), Transmission electron microscopy (TEM), Burner Emmet Taller (BET), Vibrating sample magnetometer (VSM) and thermal analysis. The SEM graphs showed that much of Fe3O4 was successfully coated by the NaP zeolite layer. Also, the results show that the magnetism of the products is stable with added zeolite. The BET and TEM confirmed the presence of mesoporous phase in the surface of NaP zeolite@Fe3O4 and preparation a micro-meso structure.

As a new product, nanoabsorbents play an important role in controlling and removing environmental pollution. Fe3O4 nanoparticles, due to their high absorption level, have a great ability to increase the efficiency of zeolite adsorbents in removing pollutants. Naeej et al. (2013) explained Zeolite modified with zero iron nanoparticles, due to having many absorption sites as a reducing agent, can have a great ability to remove nitrate from drinking water. Yaghmaian et al. (2015) investigated the removal of nitrate from aqueous solutions with zero-valent iron nanoparticles and stated that at a pH of 5.8 and a contact time of 55 minutes, more than 80% absorption is obtained. Qarlaqi et al. (2015) investigated the efficiency of iron oxide nanoparticles for urban sewage treatment. They stated that at pH equal to 3 and contact time of 15 minutes, the maximum amount of absorption is obtained. Therefore, in this study, clinoptilolite zeolite adsorbent and nano composite prepared from A Zeolite Fe3O4 nanoparticles were prepared in order to remove nitrate ions from real wastewater in industrial system. Also, zeolite treatment and zeolite- clay treatment were tested for comparison.

In this research, Fe3O4 nanoparticles were used to increase the efficiency of zeolite in removing nitrate from aqueous solutions and real wastewater. Laboratory columns made of PVC material with a height of one meter and a 100 mm diameter were used. The investigated columns were filled up to a height of 60 cm with the investigated materials and 20 cm of wastewater was continuously placed on the columns. The investigated treatments include three adsorbent materials: a) six kilograms of zeolite (clinoptilolite), b) three kilograms of zeolite and three kilograms of clay, and c) six kilograms of nanocomposite prepared from zeolite and nanomagnetic with an optimal ratio (Ratio of Zeolite: 0.5 Fe3O4) was laboratory. Synthetic wastewater with a concentration of 40 ppm was prepared and used. The temperature of the wastewater used was 20 degrees Celsius and the pH of the treated wastewater was measured as 7.2. The experiment was carried out factorially and in the form of a completely random basic design in three replications.

The results showed that the nano composite based on zeolite and Fe3O4 can absorb 70% of nitrate in a small laboratory scale and non-continuous flow. In continuous flow and on a large-scale laboratory that has industrial application, the absorption rate of nanocomposite will reach 27% after 8 hours of continuous flow. This absorption rate is 17% for zeolite-clay and 13.4% for zeolite. Decreasing the contact time and increasing the amount of wastewater in continuous flow will reduce the effect of absorbents. The results of the average comparison of the nitrate concentration in the wastewater from the columns with different absorbers show that the difference between the nitrate concentration in all measurement times between the nanocomposite absorber and the other two absorbers is statistically significant at the 1% level. Also, the results of one-way analysis of variance to compare the effect of wastewater removal on an industrial scale between the adsorbents used showed that the nanocomposite adsorbent used has more efficiency than zeolite and zeolite-clay adsorbents. Due to the fact that the composition of nanocomposite (zeolite modified with nano Fe3O4) has more surface area than zeolite and clay adsorbent due to having nano compounds, so the reactivity of this adsorbent is increased and nitrate absorption in this adsorbent is more than other adsorbents. In general, the results of this research show that the nanocomposite used in this study has a relative ability to remove nitrate from the water environment, and if the contact time is increased, it can be used on an industrial scale with a suitable absorption percentage. The current research was done with continuous flow and short contact time. This is despite the fact that in most of the investigated studies, the contact time was more than 50 minutes. Therefore, the amount of absorption is less than the laboratory scale and non-continuous flow. To solve this problem, the continuous flow system should be designed in such a way that the contact time reaches at least more than 50 minutes. In addition, with proper design, passing through the filter can be done in two stages so that maximum absorption takes place.

In this work, K-OMS compound was synthesized and then K was exchanged with Cu. In the second step Cu-OMS introduced to NaY zeolite and the synthesis zeolite/Cu-OMS hybrid materials were characterized by several techniques: Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Burner-Emmet-Taller (BET). The results showed that a new structure from zeolite and OMS was obtained. The catalytic activity of zeolite/Cu-OMS was investigated for oxidation of phenol to catechol and hydroquinone in present of hydrogen peroxide (H2O2) as oxidant in different solvents. The activity of phenol oxidation decreases in the series Cu-OMS-2/NaY>OMS-2/NaY at mild conditions. The effect of different factors such as amount of catalyst, temperature, type of oxidant and solvent was investigated. Finally, the kinetic of phenol oxidation with excess H2O2 over zeolite/M-OMS catalysts at several temperatures (40, 60 and 80 °C) was studied. These catalysts were very stable and could be reused for more than three times. The results showed a pseudo-first order kinetic with respect to phenol and the catalytic reaction occurred via a radical mechanism. Some advantages of this green catalyst are easy purification, environmental friendly, low catalyst loadings and non-toxic nature

In this paper, we have reported removal of Bisphenol A (BPA) by Hydroxyapatite/NaP zeolite (HAp: Zeolite ) nanocomposite which synthesized in previous our work and characterized by using different methods such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, Energy Dispersive X-ray analysis, surface area, and thermogravimetric analysis. To investigate the purification performance for removal BPA batch experiments were used. The results showed that the removal capacity could reach an equilibrium value of 11.125 mg/g in the initial BPA concentration of 50 mg/L. Some parameters such as initial concentration, pH, contact time, adsorbent dosage, and the temperature were studied that result shows this nanocomposite have high capacity for adsorption of BPA. The kinetic study presented that it agreed well with the pseudo-second-order model (R2= 0.994). Furthermore, thermodynamics studies were carried out, and result showed an exothermic condition for adsorption process. An artificial neural networks (ANNs) model was developed to predict the performance removal process based on experimental information which shows an association between the predicted results of the designed ANN model and experimental data. Results showed that the neural network model predicted values are found in close agreement with the batch experiment result with a correlation coefficient (R2) about 0.99051 and mean squared error 0.005938.

Background and purpose: Unwanted fertility is rarely studied among men.The aim of this study was to investigate the frequency of unintended pregnancy and its related factors in married men in South of Tehran, Iran. This descriptive-analytic study was conducted in 507 married men aged 23-49 in 2017. Demographic characteristics of the participants, their fertility history and knowledge on this issue were recorded. To analyze the data, single and multiple logistic regressions were conducted. The majority of participants reported history of pregnancy in their wives (95.1%). Approximately 37% of married men experienced at least one unwanted pregnancy. Adjusted multivariate logistic regression showed that being married more than once (AOR [Adjusted Odds Ratio], 95% CI= 2.74; 1.07-7.13), low level of comfort in the use of contraceptive methods (AOR, 95% CI= 10.06; 1.95-51.9), more than two live births (AOR, 95% CI= 2.49; 1.60-3.88), having three children and more (AOR, 95% CI= 6.70; 3.51-12.79), and doubts about marriage durability (AOR, 95% CI=0.25; 0.08-0.81) were associated with unwanted pregnanies . More focus on the factors associated with male experiences of unintended pregnancy could reduce this problem. Providing care for fertility and sexuality, trainings on the correct use of contraceptive methods to men in healthcare centers could also be of great benefit in reducing the rate of unwanted pregnancy and illegal abortions, especially in socioeconomically vulnerable populations.

A computational study of the electronic structure and stability of complexes formed between Zeolite Y and boric acid was carried out at the HF and B3LYP levels using 6-31G* basis set. Five structures located as local minimum in PES of complex (structures d, e, f, g, and h). The most stable structure is formed due to hydrogen bonding between two hydroxyl of boric acid and both oxygen of AlO2 in Zeolite (structure e).

The Nano-CrY zeolite synthesized and characterized by Fourier transfer infrared (FT-IR), X-ray diffraction (XRD),and Scanning electron microscopy (SEM).The result show that nano catalyst prepared with mainly particles size about 30-80 nm. The XRD show the structure of the zeolite does not collapse. This Nano-CrY zeolite has been used as new, and nontoxic catalyst for catalyzes of synthesis of 2-aryl-1H-benzothiazoles at mild condition. This procedure is simple, effective, inexpensive and green. The products were obtained in high yields and the catalyst is reusable. Since products were obtained by aqua work-up in good purity and complex purification methods are not necessary.

The nanocomposites of poly (Acryl amide-co-Acrylic acid) with different contents of NaA zeolite were prepared using ammonium persulfate as an initiator and N, N′-methylene bisacrylamide as the crosslinker. The morphology was characterized by SEM and the structure of nanocomposite materials was studied with XRD and FT-IR that showed the interaction between porous materials and poly (AAm-co-Aac). The adsorption behaviors of methylene blue were investigated for nanocomposites. It was shown that poly (AAm-co-AAc)/NaA nanocomposites have higher adsorption than NaA and poly (AAm-co-AAc) alone. This effect was attributed to good interaction between the hydroxyl group in porous materials and carboxylic group in poly (AAm-co-AAc) with methylene blue.