نشریه شیمی کاربردی روز
پیاپی 24 (پاییز 1391)

The desired compound was synthesized through electrochemical reduction of 1، 3-dinitro benzene under entirely controlled condition on Pb electrode and constant electrical current employing an electrochemical system containing two separated cells. The first time formation of Cyclotris meta-azo benzene was confirmed through elucidation of spectrums obtained such as 1H-NMR، 13C-NMR and 14N-NMR and also elemental analysis of H، N and C. Interestingly CV experiment provided more evidence for azo group generation. Furthermore، five structures were located computationally using B3LYP method and 6-31G and 6-31+G basis sets. Two minima، one TS and two saddle points. Spectral data calculated for structure (2) are in good agreement with experimental data.

Mercury is a toxic metal، without biological effect in human body and causes CNS and renal disease. So، removal of mercury vapor through sorbents is an important environmental problem. Due to high capability of nano particle sorbents، nano particle palladium modified on multi wall carbon nano tube (NPd-MWCNT) and single wall carbon nano tube (SWCNT) were selected for this investigation. In this study، instrumental conditions، method procedure and different effect parameters such as، absorption and adsorption efficiency، absorption capacity، temperature، time and repeatability were studied and optimized. In addition the efficiency of sorbents was compared. Absorption capacity and efficiency of sorbents depend on the amount of sorbent، kind of nano particle and mercury mass concentration. For 80 mg of sorbents، working range of NPd-MWCNT and SWCNT were achieved 0. 01-3 μg and 0. 02- 0. 7 μg respectively. Limit of detection (LOD) of NPd-MWCNT (0. 003 μg) and SWCNT (0. 006 μg) were obtained. In this research، mercury vapor was determined and produced by cold vapor atomic absorption spectrometry (CV-AAS) and mercury pilot respectively. The results show us، the maximum absorption capacity of NPd-MWCNT (8 μg g-1) was higher than SWCNT (0. 5 μg g-1) and NPd-MWCNT that had high potential mercury removal.

In this work، the comprision of phase stability of lithium silicates in the ratios of Li: Si 1:2 and 1:3 from the raw materials of lithium nitrate and silicic acid and in the ratio of Li: Si 1:2 from the raw materials of lithium sulphate and silicic acid in the temperatures of 48، 72، 96 and 120 h with using x-ray diffraction method was performed. Also، we calculated inter planar spacing (d) of the synthesized materials with using Braggs equation. Synthesized materials sizes were calculated via scherrer equation in different phases and in different Li: Si molar ratios. Cell parameters of lithium metasilicate are a=9. 392، b=5. 397 and c=4. 66 Å and the parameters for lithium disilicate are a=15. 82، b=14. 66 and c=4. 79Å. Cell parameters of lithium sodium silinaite are a=5. 06، b=8. 23 and c=14. 38Å with space group of A2/n. Results show that lithium metasilicate and lithium disilicate have space groups of Cmc21 and Ccc2، respectively.

A simple and easy method has been reported for the oxidation of alcohols using aluminum nitrate nine hydrate (Al(NO3) 3. 9H2O) as an oxidant، without any auxiliary reagent. Reactions were accomplished in solvent-free conditions with excellent or good yields at 80 C.

The vegetable oil-based epoxy materials are sustainable، renewable and biodegradable materials replacing petrochemical-based epoxy materials in some applications. Soybean oil and canola oil have high contents of unsaturated fatty acids which can be converted to epoxy fatty acids. Soybean oil containing 24. 48% oleic acid، 7. 87% Linolenic، 3. 77% Stearic، 11. 4% Palmitic and 47. 06% linoleic acid and canola oil containing 64. 27% oleic acid، 8. 8% Linolenic، 1. 27% Stearic، 3. 9% Palmitic and 17. 09% linoleic acid was epoxidised with hydrogen peroxide as oxygen donor،carrier in presence of catalytic amount of an formic acid. The highest epoxy content of epoxidiazed Soybean oil (ESO) produced had 6. 11% (wt) and The highest epoxy content of epoxidiazed canola oil ECO produced was 4. 75% (wt). A possibly undesirable side reaction was reaction of the epoxy ring opening resulting in hydroxyl functional groups observed by Fourier Transform Infrared Spectroscopy (FTIR). The result showed that the ESO was more than ECO that can related to more unsatraeted in soybean oil. This project hopes to help Iran to start producing vegetable oil-based epoxy ourselves.

Among the pollutants، chromium coming from industrials sewage is a severe danger to environment and living organisms. Therefore، removal of this harmful cation is very important from viewpoint of environment. In this research، nickel oxide nanoparticles with an average size of 18 nm were prepared by chemical precipitation method and after characterizing by X-ray diffraction (XRD) and scanning electron microscopy (SEM)، used as the sorbent for removing of Cr (III) from aqueous solutions. Also، the influences of different factors i. e. contact time، pH، sorbent amount and initial concentration of Cr (III) on removal efficiency were investigated. Evaluation of the obtained data with Langmuir and Freundlich isotherms indicates that the adsorption process is in good accordance with Langmuir model. Under optimal conditions، the maximum adsorption capacity of nickel oxide nanoparticles was found 17. 5 mg g-1.

We performed structure-activity studies upon an extended series of 36 compounds of chalcone derivatives with anti cancer biological activities in LNCaP prostate cancer cell line، using QSAR methods that imply analysis of correlations and multiple linear regression; a significant collection of six molecular descriptors was used، e. g. Edge adjacency indices، Atom-centered fragments، GETAWAY and 3D-MoRS descriptors. The obtained multi-parametric model when a different class of molecular descriptors was used led to correlation coefficient closed to 0. 922 which indicate that the model was satisfactory for prediction of the anti-cancer activity of substituted chalcones and the same compounds.

A series of Ag-doped ZnO (Ag–ZnO) catalysts with a doping concentration up to 7wt% were prepared by a direct precipitation method. The prepared photocatalysts were characterized by XRD and TEM to determine their chemical composition and surface structure. The photocatalytic activity of different Ag–ZnO catalysts was evaluated in the photocatalytic reduction of nitrate in aqueous solution under UV illumination. In the experiments، formic acid was used as a hole scavenger to enhance the photocatalytic reduction reaction. The experimental results indicate that the presence of Ag in ZnO catalysts substantially enhances the photocatalytic reaction of nitrate reduction. It was found that the optimal dosage of 5wt%Ag in ZnO achieved the fastest reaction of nitrate reduction under the experimental condition. Nitrite ions were not monitored during the reaction and a negligible amount of ammonia formed. Hence selectivity to N2 is nearly 100%.

Various methods are used to prepare potable water with environmental standards. Among them، membrane filtration has received particular attention in recent years for low operating costs، low volume wastewater and high quality water. Among the conventional membrane filtration methods، nanofiltration ones have been further developed due to high capability to remove divalent ions and low energy consumption compared to reverse osmosis membranes. In this study، performance of polymer membrane TFC-HR-100 in removal of copper ions from the copper sulfate in aqueous solutions has been investigated. Polymer membrane TFC-HR-100 from the nanofilter and composite category is used to remove divalent ions. In the experiments performed، elimination of the impurities of the divalent copper ions from aqueous solutions with concentrations ranging from 100 ppm to 5000 ppm at 5-25 bar pressures has been studied.