Number 4 Volume 13

Open Access Article

1 - First Principles calculation High Spin to Low Spin transition in the SrMnO3 and the CaMnO3 compound
Narges Saki Azadeh Aezami

In this research, structural, electronic, magnetic, and electrical properties of SrMnO3 and CaMnO3 have been investigated using calculations based on density-functional theory from scratch and Quantum-Espresso calculation code. The Hubbard parameter has been calculated More

In this research, structural, electronic, magnetic, and electrical properties of SrMnO3 and CaMnO3 have been investigated using calculations based on density-functional theory from scratch and Quantum-Espresso calculation code. The Hubbard parameter has been calculated for the Mn atom using a linear response approach and LDA+U approximation for both compounds. This parameter is 3.5 eV for CaMnO3 and it is 3.1 eV for SrMnO3. The calculations showed that even though both compounds are insulator and G-type antiferromagnetic materials. Both samples have a cubic perovskite structure in which the Mn atom is located at the center of an octagon surrounded by oxygen atoms, and the vertices of a cube are the place for Sr and Ca atoms. The effect of pressure on these two compounds has been studied from %5 to %20 in tensile pressure (TP) and compressive pressure (CP) directions along the z-axis. The transition from High Spin (HS) to Low Spin (LS) of both compounds has been searched through the results of enthalpy calculations in terms of pressure. Results reveal that both materials are in stable HS and LS states in pressures higher and lower than -10 GPa and -20 GPa, respectively. Moreover, the magnetic moment of CaMnO3 in the pressure of -20.51 GPa decreases from 3.41µB in a stable HS state to 1.44 µB in an LS state, and that of SrMnO3 in the pressure of -26.87 GPa declines from 4.37 µB in HS state to 1.55 µB in LS state. Manuscript profile

Open Access Article

2 - Synthesis and Physicochemical Characterization of New Amidic Derivative of Sodium Alginate
Shokouh Khodayar Mohammad Reza Shushizadeh Elham Tahanpesar Behzad Sharif Makhmalzadeh Haleh Sanaeishoar

In this study, our objective was to synthesis a new derivative of alginate, a natural biocompatible, biodegradable and non-toxic biopolymer to improve the gelling mechanism. For this purpose, ethylenediamine (EDA) was coupled to sodium alginate (NaA) in an aqueous-phase More

In this study, our objective was to synthesis a new derivative of alginate, a natural biocompatible, biodegradable and non-toxic biopolymer to improve the gelling mechanism. For this purpose, ethylenediamine (EDA) was coupled to sodium alginate (NaA) in an aqueous-phase reaction using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC-HCl) and N-hydroxy succinimide (NHS) as coupling reagents to synthesis ethylenediamine-grafted amphiphilic sodium alginate-amide derivative (NaA-g-EDA). Synthesized derivative showed no environmental sensitivity but the swelling percentage of hydrogels shows that hydrogels obtained from NaA-g-EDA had higher water absorption compared to non-functionalized sodium alginate. It seems that hydrogels can uptake water more than 100% of their weight but in a slow manner. This character is a perfect property for wound dressing. Biodegradable synthesized hydrogel can be decomposed into non-toxic by-products. The purity and grafting of copolymers were characterized using fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), X-ray diffraction (XRD), and elemental analysis (CHNX). These analytical methods confirmed the structure of NaA-g-EDA. Manuscript profile

Open Access Article

3 - New results on the extraction of Lithium ions from salt lake brine using ionic liquid tributyl phosphate
Abdloreza Hormati Bahram Rezai Hadi Hamidian Shoormasti Ghodratollah Rostami Paydar

Lithium is a light metal with outstanding physical and chemical properties with many applications in the modern world. The concentration of lithium in sea water is on average 0.17 ppm and in the effluent of such a unit, it should be increased to 350 ppm on average. In t More

Lithium is a light metal with outstanding physical and chemical properties with many applications in the modern world. The concentration of lithium in sea water is on average 0.17 ppm and in the effluent of such a unit, it should be increased to 350 ppm on average. In this study, 1-hexyl-3-methylimidazolium [C6mim+] as cation and bis (trifluoromethylsulfonyl) imide [NTf2-] as anion of ionic liquid (ILS) using the neutral tributyl phosphate (TBP) were developed for efficient extraction of lithium ions (Li+) from Salt Lake Brine. The effective parameters on lithium ions extraction process were studied including solution pH (~ 7), adsorbent dosage (100 & 300 mg) and extraction time (30 & 120 min). The extraction efficiency of lithium ion was 94 % fir ILS under the optimal conditions. The adsorption rate, adsorption capacity and mechanism are examined with applying the kinetic, isotherm and free energy models on experimental data. The Langmuir isotherm proposed adsorption capacity of 62.5 mg/g for ILs , respectively. This indicated multi-layer pattern for ILs. Free energy model is suggested a physical sorption mechanism for lithium ions. The obtained results are preformed the green ILs can be used as alternative extractant for Li+ from salt lake brine. Manuscript profile

Open Access Article

4 - Spectroscopic study of diphenyl [(S)-(–)-1-phenylpropanamido]-phosphate: differences of diastereotopic groups
Farnaz Eslami Mehrdad Pourayoubi Fahimeh Sabbaghi Sahar Baniyaghoob

Abstract The synthesis and crystal structure of diphenyl [(S)-(–)-1-phenylpropanamido]-phosphate, (C6H5O)2P(O)[NH-(S)-(–)CH(C2H5)(C6H5)], was previously reported. Here, the spectroscopic features (1H-NMR, 13C{1H}-NMR, 31P{1H}-NMR and IR) are investigated. In the 1H-NMR More

Abstract The synthesis and crystal structure of diphenyl [(S)-(–)-1-phenylpropanamido]-phosphate, (C6H5O)2P(O)[NH-(S)-(–)CH(C2H5)(C6H5)], was previously reported. Here, the spectroscopic features (1H-NMR, 13C{1H}-NMR, 31P{1H}-NMR and IR) are investigated. In the 1H-NMR and 13C{1H}-NMR spectra, the diastereotopic C6H5O groups show two sets of signals. Typically, in the 13C{1H}-NMR spectrum, the doublets at 151.08/151.20 ppm and 120.52/120.55 ppm, with 2JCP = 6.5/6.6 Hz for the first pair and 3JCP = 4.9/4.7 Hz for the second pair are associated to the diastereotopic ipso-C atoms and diastereotopic ortho-C atoms. In the 1H-NMR spectrum, the signals related to diastereotopic phenyl groups overlap with those of phenyl group of chiral amine. The ipso-carbon atom of chiral amine fragment appears a doublet signal at 144.85 ppm (3JCP = 2.7 Hz). The phosphorus signal (31P{1H}-NMR) appears at –0.49 ppm. in this work NMR and spectroscopic main part are going to be consider and proved because of the chiral importance in drug delivery. Keywords: Amidophosphodiester; IR; NMR; Phosphorus-carbon coupling constant Manuscript profile

Open Access Article

5 - Ultrasound- and Magnetic Assisted Dispersive-Micro-Solid-Phase Extraction followed by Atomic Absorption Spectrometry based on Carbon Quantum Dots Functionalized with Magnetite/Zeolitic Imidazolate Framework 71/Polypyrrole for Determination and Trace Monitoring of Pb (II) in Water and Food Samples
Elnaz Nakhostin Mortazavi Mohsen Zeeb Seyed Saied Homami

In this search, an ultrasound-and magnetic-assisted dispersive micro-solid-phase extraction (US-M-A-DMSPE) was developed for selective separation of Pb ion by an innovative nanocomposite based on carbon quantum dots functionalized with magnetite/zeolitic imidazolate fra More

In this search, an ultrasound-and magnetic-assisted dispersive micro-solid-phase extraction (US-M-A-DMSPE) was developed for selective separation of Pb ion by an innovative nanocomposite based on carbon quantum dots functionalized with magnetite/zeolitic imidazolate framework 71/polypyrrole. To fabricate the novel nanocomposite, first, the magnetized carbon quantum dot was functionalized by imidazolate zeolite-71, and then pyrrole was utilized as an oxidant agent in the chemical polymerization on the surface of magnetic carbon quantum dot functionalized with zeolitic imidazolate framework 71. Lead was analyzed by flam atomic absorption spectrometry (FAAS). The structure of nanosorbent was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray analyzer (EDX), vibrating sample magnetometry (VSM) and Fourier transform-infrared (FT-IR). To maximum recoveries of Pb (II), the optimum experimental conditions and analytical parameters such as amount of sorbent, pH of samples, ultrasonic time, chelating agent concentration, ionic strength, volume of desorbing solvent and reusability were estimated. Under the optimal conditions, the preconcentration factor was achieved 60. The limits of detection and quantification were found to be 0.15 ng mL−1 and 0.5 ng mL−1, respectively. The relative standard deviations (RSD%) of the developed US-M-A-DMSPE process is below was 2.9 %. The present process was successfully applied to the determination of Pb2+ ion at trace levels in water and food samples by ultrasound-and magnetic-assisted dispersive micro-solid-phase extraction tandem flame atomic adsorption spectroscopy (US-M-A-DMSPE-FAAS) and its validation was investigated by recovery experiments and analyzing certified reference material. Manuscript profile

Open Access Article

6 - Studies on Mechanism of Formation and Medicinal applications of structurally diverse Indole and Oxindole derivatives
Noor ud Din Zargar Khaliq Zaman Khan

The field of heterocyclic chemistry is vast and has played a significant role in synthetic organic chemistry. Heterocyclic compounds and methods for their synthesis form the bedrock of modern medicinal and pharmaceutical research. Indoles and Oxindoles are the most stud More

The field of heterocyclic chemistry is vast and has played a significant role in synthetic organic chemistry. Heterocyclic compounds and methods for their synthesis form the bedrock of modern medicinal and pharmaceutical research. Indoles and Oxindoles are the most studied bicyclic nitrogen heterocycles. The selective acylation of indoles often requires sensitive and reactive acyl chloride derivatives. A chemoselective N-acylation of indoles1 using thioesters 2 as a stable acyl source has been reported. Interaction of 1-acylindoles 10 with acetyl chloride in the presence of AlCl3 yields the corresponding 1- acyl-3-acetylindoles 11 which upon hydrolysis affords 3-acetylindole12.Addition of (1Hindol- 3-yl) magnesium iodide (16) to 2-(benzyloxy) acetyl chloride 17 in diethyl ether forms 3-benzyloxyacetylindole 18. Acylation of Oxindole 20 with chloroacetyl chloride affords 5- chloromethyl ketone derivatives31whichwhen treated with thioureas and thioamides leads to the formation of 5-thiazole oxindoles32.This article focuses on various synthetic methods and suggested mechanism of different indole and oxindole derivatives.Apart from this, applications of medicinal importance of these heteroatom compounds have also been discussed. Manuscript profile

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