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1.
J Mol Model ; 27(2): 45, 2021 Jan 23.
Article in English | MEDLINE | ID: mdl-33484343

ABSTRACT

We investigated the possible use of a hexa-cata-hexabenzocoronene nanographene (HCHN) as an anode material for Mg-ion batteries (MIBs) implementing the B3LYP-gCP-D3/6-31G* scheme. The Mg cation or atom is adsorbed on the HCHN with the adsorption energy of - 200.3 or - 4.7 kcal/mol. The energy barrier related to transferring Mg cation on the HCHN surface was calculated to be 7.5 kcal/mol, producing the diffusion coefficient of 1.90 × 10-8 cm2/s. It shows that the ion mobility is high and the rate of charge or discharge is fast. The calculated specific storage capacity of HCHN is 589.4 mAh/g and the great cell voltage is 4.23 V that is generated by the interaction of cation-π between Mg2+ and HCHN, which is strong. The HCHN is considered an ideal candidate to be used as an anode material in MIBs since its storage capacity and ion mobility are high, and it has a large cell voltage.

2.
Top Curr Chem (Cham) ; 377(4): 20, 2019 Jul 04.
Article in English | MEDLINE | ID: mdl-31273478

ABSTRACT

Form a green and sustainable chemistry point of view, cross-dehydrogenative coupling (or oxidative cross-coupling) reactions have been recognized as environmentally sustainable and atom economical synthetic routes for the construction of new carbon-carbon and carbon-heteroatom bonds, since no pre-functionalization of starting materials is required. In the past few years, the direct coupling of sp-hybridized C-H bonds with heteroatom-H bonds has received much attention because of the importance of heteroatom-substituted alkynes in organic and medicinal chemistry. This review examines the recent developments in cross-dehydrogenative coupling reactions between C(sp)-H and X-H (X = N, P, S, Si, Sn) bonds, with a particular focus on the mechanistic aspects of the reactions.


Subject(s)
Alkynes/chemistry , Carbon/chemistry , Hydrogen/chemistry , Hydrogenation , Nitrogen/chemistry , Phosphorus/chemistry , Silicon/chemistry , Sulfur/chemistry , Tin/chemistry
3.
Talanta ; 162: 505-510, 2017 Jan 01.
Article in English | MEDLINE | ID: mdl-27837863

ABSTRACT

OZONE is a key species in forming a layer in the atmosphere of earth that brings vita for our planet and supports the complex life. This three-atom molecule in the ozone-layer, is healing the earth's ecosystem by protecting it from dangerous rays of the sun. Until this molecule is in the stratosphere, it would support the natural order of the life; but, when it appears in our environment, damages will begin against us. In this project, we have tried to find a new way for beaconing ozone species in our environment via physical adsorption by the C20 fullerene and graphene segment as a sensor. To find the selectivity of this nano-sized segment in sensing ozone (O3), compared to the usual chemically active gasses of the troposphere like O2, N2, CO2, H2O, CH4, H2, and CO, the density of state (DOS) plots were analyzed, for each interacting species. The results showed that ozone could significantly change the electrical conductivity of C20 fullerene, for each adsorption step. Thus, this fullerene could clearly sense ozone in different adsorption steps; while, the graphene segment could do this only at the second step adsorption (/ΔEg-B/=0.016eV) (at the first adsorption step the /ΔEg-A/ is 0.00eV).

4.
Sci Pharm ; 81(1): 281-96, 2013.
Article in English | MEDLINE | ID: mdl-23641345

ABSTRACT

The present research work describes the synthesis and evaluation of new acrylic-type polymeric systems having degradable ester bonds linked to ibuprofen as materials for drug delivery. Ibuprofen was linked to 2-hydroxy-propyl methacrylate by an activated ester methodology in a one-pot procedure with a high yield. The resulting material was copolymerized with either 2-hydroxyethyl methacrylate or methyl methacrylate (in 1:3 mole ratios) by the free radical polymerization method, utilizing azoisobutyronitrile at 65-70 °C. The characterization of the resulting products by FTIR, (1)H NMR, (13)C NMR, DSC, and elemental analysis confirmed their synthesis successfully. Ibuprofen release from the obtained polymers was preliminarily evaluated at different buffered solutions (pH 1, 7.4, and 10) into dialysis bags to show the capacity of prodrugs to release the drug under hydrolytic conditions. Detection of hydrolysis by UV spectroscopy at selected intervals showed that the drug can be released by selective hydrolysis of the ester bond at the side of the drug moiety. The release profiles indicated that the hydrolytic behavior of polymers is strongly based on the polymer hydrophilicity and the pH value of the hydrolysis solution. The results suggest that these polymers could be useful in controlled release systems.

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