Aluminum oxide (ALO) was grafted by acrylic acid monomer (AlO-AM) and then, it was polymerized to produce alumina grafted poly(acrylic acid) (AlO-AP). The prepared AlO-AM and AlO-AP were characterized by Fourier-transform infrared, differential scanning calorimetry , thermogravemetric analyzer and particle size distribution. Adsorption equilibrium isotherms, adsorption kinetics and thermodynamic studies of the batch adsorption process were used to examine the fundamental adsorption properties of phenol (P) and p-chlorophenol (PCP). The experimental equilibrium adsorption data were analyzed by three widely used two-parameters Langmuir, Freundlich and DubininRadushkevich isotherms. The maximum P and PCP adsorption capacities based on the Langmuir isotherm were calculated at 56.818, 78.741, 92.593, 80.002, 103.579 and 131.579 mg/g for P and PCP onto ALO, AlO-AM and AlO-AP, respectively. The experimental kinetic data were analyzed by using Pseudo-first order and pseudo-second order kinetic models. A comparison of the kinetic models on the overall adsorption rate showed that the adsorption system can be best described by the pseudo-second order kinetics. Based on the calculated thermodynamic parameters such as enthalpy (DH°), entropy (DS°) and Gibb’s free energy changes (DG°). The negative DG° and DH° values indicated that the adsorption of P and PCP by AlO-AM and AlO-AP adsorbent was feasible, spontaneous and the process was exothermic in nature.
Objectives: This study aims to assess and compare the micro-shear bond strength (μSBS) of a novel resin-modified glass-ionomer luting cement functionalized with a methacrylate co-monomer containing a phosphoric acid group, 30 wt% 2-(methacryloxy) ethyl phosphate (2-MEP), with different substrates (dentin, enamel, zirconia, and base metal alloy). This assessment is conducted in comparison with conventional resin-modified glass ionomer cement and self-adhesive resin cement. Materials and methods: In this in vitro study, ninety-six specimens were prepared and categorized into four groups: enamel (A), dentin (B), zirconia (C), and base metal alloys (D). Enamel (E) and dentin (D) specimens were obtained from 30 human maxillary first premolars e
... Show MoreCsaszar introduced the concept of generalized topological space and a new open set in a generalized topological space called -preopen in 2002 and 2005, respectively. Definitions of -preinterior and -preclosuer were given. Successively, several studies have appeared to give many generalizations for an open set. The object of our paper is to give a new type of generalization of an open set in a generalized topological space called -semi-p-open set. We present the definition of this set with its equivalent. We give definitions of -semi-p-interior and -semi-p-closure of a set and discuss their properties. Also the properties of -preinterior and -preclosuer are discussed. In addition, we give a new type of continuous function
... Show MoreThe aim of this paper is to introduce a new type of proper mappings called semi-p-proper mapping by using semi-p-open sets, which is weaker than the proper mapping. Some properties and characterizations of this type of mappings are given.
The purpose of this paper is to introduce a new type of compact spaces, namely semi-p-compact spaces which are stronger than compact spaces; we give properties and characterizations of semi-p-compact spaces.
A thin film of AgInSe2 and Ag1-xCuxInSe2 as well as n-Ag1-xCuxInSe2 /p-Si heterojunction with different Cu ratios (0, 0.1, 0.2) has been successfully fabricated by thermal evaporation method as absorbent layer with thickness about 700 nm and ZnTe as window layer with thickness about 100 nm. We made a multi-layer of p-ZnTe/n-AgCuInSe2/p-Si structures, In the present work, the conversion efficiency (η) increased when added the Cu and when used p-ZnTe as a window layer (WL) the bandgap energy of the direct transition decreases from 1.75 eV (Cu=0.0) to 1.48 eV (Cu=0.2 nm) and the bandgap energy for ZnTe=2.35 eV. The measurements of the electrical properties for prepared films showed that the D.C electrical conductivity (σd.c) increase
... Show MoreUnused and expired pharmaceutical drugs are a novel type of organic corrosion inhibitor. They are less expensive, more effective, and less harmful than conventional organic corrosion inhibitors. This study investigated the effects of concentration, adsorption mechanism and thermodynamic parameters of enalapril malate (ENAP) as a corrosion inhibitor for carbon steel in a saline solution (3.5 % NaCl). The polarization method was used to determine the corrosion rate and inhibition efficiency. Field emission scanning electron microscopy (FE-SEM) and atomic force spectroscopy (AFM) were used to investigate the surface morphology and topography of carbon steel after immersion in both uninhibited and inhibited media for 24 h. Fourier transform inf
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