Original Research Article
Sedigheh Rostami; Seyed Naser Azizi; Neda Asemi
Abstract
In this study, hierarchical H-ZSM-5 zeolite is prepared via post-synthetic modification of parent H-ZSM-5 zeolite (Si/Al=35) synthesized from bagasse (BGA) as silica source using desilication with alkaline treatment (AT). For optimizing the effective parameters on desilication, Taguchi method was utilized. ...
Read More
In this study, hierarchical H-ZSM-5 zeolite is prepared via post-synthetic modification of parent H-ZSM-5 zeolite (Si/Al=35) synthesized from bagasse (BGA) as silica source using desilication with alkaline treatment (AT). For optimizing the effective parameters on desilication, Taguchi method was utilized. Cultivated BGA in the south of the Caspian Sea (Mazandaran province, Iran) is applied for extracting silica powder and used in the synthesis of zeolite. In this work, two responses have been considered. The First and the second responses are the maximum amounts of extracted silicone and the removal of Pb2+ % from aqueous solutions, respectively. For this purpose, the effect of four important factors with three selected levels including; concentration of NaOH solution (0.1, 0.2 and 0.5 M), temperature (25, 55 and 85 Cº), time of reflux (30, 60 and 120 min) and molar ratio of TMAOH/ NaOH (0.5, 1 and 1.5) are studied on both of the responses. TMAOH was defined as tetra methyl ammonium hydroxide. According to Taguchi method, the optimum conditions for both responses are concluding as Concentration of NaOH solution=0.2 M, temperature =55 Cº, time of reflux=120 min and molar ratio of TMAOH/ NaOH=0.5. The results display that Concentration of NaOH solution in comparison to other factors is the most effective one in both responses. Also, AT-05-ZSM-5 is selected as the optimum zeolite with volumes 278.13 ppm and 90.2 % with S/N ratios 48.878 and 39.097 for the first and the second responses, respectively. Parent H-ZSM-5 and AT-05-ZSM-5 are characterized by x-ray diffraction (XRD), scanning electronic microscopy (SEM), Fourier transform infra-red (IR), Brunauer–Emmett–Teller (BET), Barrett-Joyner-Halenda (BJH) and inductively coupled plasma-optical emission spectrometery (ICP-OES). AT-05- ZSM-5 demonstrates a limit and uniform meso-pore average size distribution at 7.65 nm using alkaline treatment.
Original Research Article
Sohrab Ershad; Razieh Mofidi Rasi
Abstract
The redox properties of sulfite ion has been examind using cyclic voltammetry in acetonitrile solvent at the surface of gold, pelatin and glassy carbon electrodes. It has bben found tha, sulfite ion exhibits two electron oxidation peak with EC’ mechanism. A novel chemically modified electrode containing ...
Read More
The redox properties of sulfite ion has been examind using cyclic voltammetry in acetonitrile solvent at the surface of gold, pelatin and glassy carbon electrodes. It has bben found tha, sulfite ion exhibits two electron oxidation peak with EC’ mechanism. A novel chemically modified electrode containing Prussian blue complex and multi wall carbon nanotubes (MWCNs) was achieved on the surface of glassy carbon electrode by sol-gel technique. The electrochemical behavior of modified electrode was characterized by cyclic voltammetry in detail. The film electrode obtained was very stable and exhibited electrocatalytic response for oxidation of sulfite. Results showed at bare GC electrode, a small oxidation peak current was observed at about 0.663mV and a well-formed sharp catalytic oxidation peak was observed at Prussian blue complex modified electrode. The transfer coefficient (α) for electrocatalytic oxidation of sulfite and the diffusion coefficient of this substance under the experimental conditions were also investigated.
Original Research Article
Bakhtiar Khodavirdilo; Naser Samadi; Reza Ansari
Abstract
In this study a new method by Application of graphene oxide Nano sheets– Melamine –TioOxalic acid composite was exhibited as adsorbent for the elimination of toxic mercury (II) ions from aqueous solutions. The combine has the authority to adsorb the organic and inorganic combines. Through ...
Read More
In this study a new method by Application of graphene oxide Nano sheets– Melamine –TioOxalic acid composite was exhibited as adsorbent for the elimination of toxic mercury (II) ions from aqueous solutions. The combine has the authority to adsorb the organic and inorganic combines. Through the immobilization of Melamine-TioOxalic acid (MTO) onto graphene oxide nanosheets, the desired composite was synthesized and introduced by field emission scanning electron microscopy (FE-SEM), UV-Vis and Fourier transform infrared (FT-IR) spectroscopic techniques. The different experimental parameters such as pH and concentration of the aqueous solution of Mercury (II), amounts of the MTO and the graphene oxide (GO), temperature, contact time, have been optimized. It was presented that they carry out the efficiency of Mercury (II) ion importantly, increased after immobilization of MTO on the graphene oxide Nano sheets. GO-MTO is a very suitable adsorbent for removing of heavy metal ions especially Mercury (II) ions. Mercury and Gold have very interesting for binding with sulfur.
Original Research Article
Zahra Rostami; Eslam Pourbasheer
Abstract
A comparative workflow, including linear and non-linear QSAR models, was carried out to evaluate the predictive accuracy of models and predict the inhibition activity of a series of aryl-substituted isobenzofuran-1(3H)-ones. The data set consisted of 34 compounds was classified into the training and ...
Read More
A comparative workflow, including linear and non-linear QSAR models, was carried out to evaluate the predictive accuracy of models and predict the inhibition activity of a series of aryl-substituted isobenzofuran-1(3H)-ones. The data set consisted of 34 compounds was classified into the training and test sets, randomly. Molecular descriptors were selected using the genetic algorithm (GA) as a feature selection tool. Various linear models based on multiple linear regression (MLR), principle component regression (PCR) and partial least square (PLS) and non-linear models based on artificial neural network (ANN), adaptive network-based fuzzy inference system (ANFIS) and support vector machine (SVM) methods were developed and compared. The accuracy of the models was studied by leave-one-out cross-validation (Q_LOO^2), Y-randomization test and group of compounds as external test set. Six descriptors were selected by GA to develop predictive models. With respect to the linear models, GA-PCR method was more accurate than the reset with statistical results of 〖 R〗_train^2=0.883, R_test^2=0.897,〖 R〗_(adj,train)^2=0.829,〖 R〗_(adj,test)^2=0.849,〖 F〗_train=24.07 and F_test=34.17. In case of non-linear models, GA-SVM (R_train^2=0.992 and R_test^2=0.997) showed high predictive accuracy for the inhibitory activity. It was found that the selected descriptors have the major roles in interpretation of biological activities of the compounds.
Original Research Article
Navabeh Nami; Mahmoud Tajbakhsh; Mohamad Vafakhah
Abstract
Synthesis of indole derivatives was investigated and compared to the reaction of phenylhydrazine and ketones in the presence of the heterogeneous catalysts like kaolinite, montmorillonite K10 and Fe3O4 MNPs in ethanol under reflux conditions. After comparing the HPLC chromatogram of products it was compared ...
Read More
Synthesis of indole derivatives was investigated and compared to the reaction of phenylhydrazine and ketones in the presence of the heterogeneous catalysts like kaolinite, montmorillonite K10 and Fe3O4 MNPs in ethanol under reflux conditions. After comparing the HPLC chromatogram of products it was compared and found that kaolin and montmorillonite K10 are better and more efficient candidate than Fe3O4 magnetic nanoparticles for synthesis of indole derivatives. The synthesized compounds have been characterized by 1H-NMR and 13C-NMR. The advantages of this reaction are short reaction time, mild reaction conditions, high catalytic activity in green chemistry, increasing reaction speed without air pollution and good yields.
Original Research Article
Homa Shafiekhani; Zoheir Hagh’goo; Shahriyar Bahar
Abstract
For spectrophotometric analysis of Hg (II) ions, we have used and compared two membranes preparation methods using different polymer; one is poly(vinyl chloride) (PVC) and the other is triacetylcellulose (TAC). In the case of TAC membrane, it was treated with a ligand solution (1.166 × 10-3 mole ...
Read More
For spectrophotometric analysis of Hg (II) ions, we have used and compared two membranes preparation methods using different polymer; one is poly(vinyl chloride) (PVC) and the other is triacetylcellulose (TAC). In the case of TAC membrane, it was treated with a ligand solution (1.166 × 10-3 mole L-1) in ethylenediamine at the ambient temperature for almost 2-5 min. However, in the case of PVC membrane, the ligand of triazen was incorporated into a plasticized membrane of PVC. The significant factors affecting the determination of analytical performance from aqueous solutions, limit of detections (LODs) by TAC membrane (64 µg L-1) and by PVC membrane (0.069 ng L-1), linear dynamic range (DLR) by TAC membrane (7-90 mg L-1) and by PVC membrane (0.125-10 µg L-1). In this work LODs and linear dynamic range of PVC membrane is lower than of TAC membrane by a factor of 10000. However, TAC membrane was easier to operate and no more special device required, but PVC membrane required much shorter time reaching to steady state. Two membranes were successfully applied to the determination of Hg (II) in water samples.
Short Communication
Aliakbar Dehno Khalaji
Abstract
In this study, mononuclear octahedral cobalt(III) Schiff base complex [CoL3], L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, was synthesized from the reaction of Co(NO3)2•6H2O and the Schiff base ligand L in methanol as solvent. It used as a new precursor to prepare spinel type cobalt oxide nanoparticles ...
Read More
In this study, mononuclear octahedral cobalt(III) Schiff base complex [CoL3], L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, was synthesized from the reaction of Co(NO3)2•6H2O and the Schiff base ligand L in methanol as solvent. It used as a new precursor to prepare spinel type cobalt oxide nanoparticles by a facile solid-state thermal decomposition. Controlling the temperature and time, Co3O4 nanoparticles were obtained in air at 550ºC within 3.5 h. The Co3O4 nanoparticles was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These results confirm that the resulting cobalt oxide products were pure single-phases. Using the present method, Co3O4 nanoparticles can be produced without using any expensive organic solvent and complicated equipment. TEM result showed the products are almost flat with the size of about 10-50 nm. It has potential to be applied as a general method for preparation of other transition metal oxide nanoparticles.
Original Research Article
Mona Ashtary; Ali Ramazani; Morteza Rouhani
Abstract
Reactions of N-isocyaniminotriphenylphosphorane with a cyclic ketone in the presence of ferrocene carboxylic acid proceeded smoothly at room temperature and in neutral conditions to afford ferrocene-containing 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under ...
Read More
Reactions of N-isocyaniminotriphenylphosphorane with a cyclic ketone in the presence of ferrocene carboxylic acid proceeded smoothly at room temperature and in neutral conditions to afford ferrocene-containing 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed. The structures of the products were deduced from their IR, 1HNMR, and 13CNMR spectra. The method offers a mild, simple, and efficient route for the preparation oreaction of N-isocyaniminotriphenylphosphorane with cyclic ketones in the presence of ferrocene carboxylic acid proceeded smoothly at room temperature and in neutral conditions to afford ferrocene-containing 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed. The structures of the products were deduced from their IR, 1HNMR, and 13CNMR spectra. f sterically congested ferrocene-containing 1,3,4-oxadiazole derivatives from cyclic ketones, N-isocyaniminotriphenylphosphorane (Ph3PNNC) and ferrocene carboxylic acid. Its ease of workup, high yields and fairy mild reaction conditions make it a useful addition to modern synthetic methodologies.
)
)
)
)
)
)
)
)