Caro's Acid-Silica Gel Catalyzed Regioselective Ring Opening of Epoxides with Indoles and Imidazoles under Solvent-Free Conditions
Majid Momahed
Heravi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Hoda
Hamidi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Narges
Karimi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Akram
Amouchi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
text
article
2018
eng
An efficient and facile procedure has been developed for the ring opening of epoxides with nitrogen heterocycles such as indole and imidazole in the presence of Caro's acid-silica gel (CA-SiO2) as catalyst in solventless system. The reactions were administered underneath Solvent-free conditions. The current methodology offers many benefits like good yields, easy procedure, simple work-up and ecofriendly reaction condition. The catalyst is well ready, stable and economical underneath the reaction conditions.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
1
6
http://www.ajchem-a.com/article_78187_7edc753e802565c97e7fd25f0e76b191.pdf
dx.doi.org/10.29088/sami/AJCA.2018.1.16
One-Pot Synthesis of Tetracyanocyclopropane Derivatives Using Hexamethylenetetramine-Bromine (HMTAB)
Majid Momahed
Heravi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Hossein
Abdi Oskooie
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Zahra
Latifi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
Hoda
Hamidi
Department of Physics and Chemistry, Alzahra University, Tehran,P.O. Box 1993891176, Iran
author
text
article
2018
eng
Herein a direct method for synthesis of tetracyanocyclopropanes by the treatment of carbonyl compounds, malononitrile and hexamethylenetetramine-bromine (HMTAB) is described in the presence of catalytic amount of DABCO in ethanol media at room temperature.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
7
11
http://www.ajchem-a.com/article_79156_9a7a8c018b7b203b7769ddd0099cb98b.pdf
dx.doi.org/10.29088/sami/AJCA.2018.2.711
Prediction of Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry Retention Times of 160 Pesticides and 25 Environmental Organic Pollutants in Grape by Multivariate Chemometrics Methods
Issa
Amini
Department of Chemistry, Payame Noor University, P.O. BOX 19395-4697, Tehran, Iran
author
Kaushik
Pal
Department of Nanotechnology, Bharath University,BIHER Research Park, Chennai, Tamil Nadu 600073, India
author
Sharmin
Esmaeilpoor
Department of Chemistry, Payame Noor University, P.O. BOX 19395-4697, Tehran, Iran
author
Aydi
Abdelkarim
Department of Chemical and Materials Engineering, College of Engineering, National College of Chemical Industry, Nancy, Polytechnic Institute of Lorraine, France Frankfurt Am Main Area, Germany
author
text
article
2018
eng
A quantitative structure–retention relation (QSRR) study was conducted on the retention times of 160 pesticides and 25 environmental organic pollutants in wine and grape. The genetic algorithm was used as descriptor selection and model development method. Modeling of the relationship between selected molecular descriptors and retention time was achieved by linear (partial least square; PLS) and nonlinear (kernel PLS: KPLS and Levenberg-Marquardt artificial neural network; L-M ANN) methods. The QSRR models were validated by cross-validation as well as application of the models to predict the retention of external set compounds, which did not have contribution in model development steps. Linear and nonlinear methods resulted in accurate prediction whereas more accurate results were obtained by L-M ANN model. The best model obtained from L-M ANN showed a good R2 value (determination coefficient between observed and predicted values) for all compounds, which was superior to those of other statistical models. This is the first research on the QSRR of the compounds in wine and grape against the retention time using the GA-KPLS and L-M ANN.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
12
31
http://www.ajchem-a.com/article_79238_3f0262dc82e511c53316615b54888676.pdf
dx.doi.org/10.29088/sami/AJCA.2018.3.1231
Heat Transfer and Fluid Flow Analysis of a Novel Micro-Miniature Cryocooler Model
Hussayn
Bakhshy
Department of Electrical and Computer Engineering, MalekAshtar University of Technology, Lavizan Street,
15875-1774, Tehran, Iran
author
Seyyed Mohammad Ali
Rohani
Department of Electrical and Computer Engineering, MalekAshtar University of Technology, Lavizan Street,
15875-1774, Tehran, Iran
author
Payam
Heydari
Department of Engineering, Roudehen Branch, Islamic Azad University, Roudehen, Iran
author
Reza
Asadi
Department of Electrical and Computer Engineering, MalekAshtar University of Technology, Lavizan Street,
15875-1774, Tehran, Iran
author
text
article
2018
eng
In the current study, a new model for micro-scale cooling systems is presented. The small-scale refrigerator is modeled by engraving channels and a micro nozzle on the sides of a rectangular glass. The system has the capability to reduce the temperature from 300K to 80 in 5 seconds using nitrogen as the working fluid. The model consists of three elements, heat exchanger, nozzle and expansion tank and all the parts of the cooling system is stationary. For this novel model, pressure drop through the channels and nozzle sections is presented and by using these information, temperature drop through the nozzle is obtained regarding the high Mach number at the throat of the convergence-divergence micro-nozzle. Due to the characteristics of this in-plane micro-nozzle, the heat exchange is modeled through the time in the glass, and temperature of the cooling system is reported.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
32
38
http://www.ajchem-a.com/article_79533_8e44cd3d0b651d35b39a784f7252a1b3.pdf
dx.doi.org/10.29088/sami/AJCA.2018.4.3238
Determination of Acetaminophen using a Glassy Carbon Electrode Modified by Horseradish Peroxidase Trapped in MWCNTs/Silica Sol-Gel Matrix
Javad
Ghodsi
Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran
author
Amir Abbas
Rafati
Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran
author
Yalda
Shoja
Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran
author
text
article
2018
eng
A new and easy to fabricate voltammetric biosensor for acetaminophen determination was developed based on horseradish peroxidase (HRP) trapped between silica sol-gel film and multi-walled carbon nanotubes on glassy carbon electrode. Acetaminophen determinations were carried out in presence of H2O2 as enzyme activator. The modified electrode showed excellent electrocatalytic activity and rapid response to acetaminophen in the presence of H2O2 as enzyme activator. Various parameters influencing the biosensor performance such as amount of enzyme, H2O2 concentration, potential scan rate and pH have been investigated. Under the optimal conditions, a wide linear range of 1.85×10−6 to 2.7×10−3 M for acetaminophen determination was obtained. Limit of detection was calculated about 18 nM and sensitivity was about 220 nA/µM. Furthermore, the proposed biosensor was successfully examined for simultaneous determination of acetaminophen with uric acid (UA) and folic acid (FA) as prevalent interferes. The proposed biosensor showed satisfactory stability for 3 weeks and applicability of developed biosensor was confirmed with accurately evaluation of acetaminophen in real samples such as urine and tablet.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
39
55
http://www.ajchem-a.com/article_79902_6e93f0e5649963786af17a373db7489b.pdf
dx.doi.org/10.29088/sami/AJCA.2018.5.3955
Synthesis and Chemical Modification of Maleic Anhydride Copolymers with 2-Amino Ethyl Benzoate Groups
Mohammad Hosein
Nasirtabrizi
Department of Applied Chemistry, Ardabil Branch, Islamic Azad University, Ardabil, Iran
author
Seid Jafar
Mousavi
Department of Applied Chemistry, Ardabil Branch, Islamic Azad University, Ardabil, Iran
author
text
article
2018
eng
Maleic anhydride (MAN) copolymers with methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and butyl acrylate monomers at 1:3 mole ratios were synthesized by free radical polymerization in the presence of azobis(isobutyronitrile) as initiator and dry ethyl acetate as solvent. Copolymer compositions were obtained using related proton nuclear magnetic resonance (1HNMR) spectra, and the polydispersity of the copolymers was determined by gel permeation chromatography. Then, a solution of 2-amino ethyl benzoate salt as a nucleophilic reagent reacted through the ring opening of anhydride groups in copolymers resulting to modified copolymers Iab to Vab. All the prepared polymers were characterized by Fourier transform infrared and1H NMR spectroscopic techniques. The glass transition temperature (Tg) of all copolymers before and after modification was determined by dynamic mechanical thermal analysis (DMTA). It was shown that chemical modification of MAN copolymers with 2-amino ethyl benzoate substituents as side chains decreased the free volume of the polymers, and therefore, the rigidity and Tg are increased.
Advanced Journal of Chemistry, Section A
Sami Publishing Company
2645-7768
1
v.
1
no.
2018
56
65
http://www.ajchem-a.com/article_79929_e4c173319818e5c52aaf8a57a920a22f.pdf
dx.doi.org/10.29088/sami/AJCA.2018.6.5665