Open Access Original Research Article

Mg2Cu Alloy Preparation by Mechanical Alloying Process and Its Characterization Using X-ray Diffraction and Scanning Electron Microscopy

José Luis Iturbe-Garcia, Beatriz Eugenia López-Muñoz, Luis Zamora Rangel

Chemical Science International Journal, Page 1-9
DOI: 10.9734/ACSJ/2016/22845

In this work the synthesis of intermetallic Mg2Cu is presented. Elemental particles of magnesium with a purity of 99.8% and Cu 99.9% were mixed in desired quantity to reach a nominal composition of 40-60 and 80-20 wt% for magnesium and copper in each composition respectively. The synthesis of compound was carried out by mechanical alloying technique with a high energy ball mill type spex which was constructed in our Institute. Then Mg and Cu particles were put into a stainless steel vial and three stainless steel balls and methanol as milling media and process control agent respectively. The ball to particles weight ratio was 10:1. The milling time was defined only between 1 to 5 h, at room temperature. This technique was used because the conventional method of thermal fusion could not be induced to synthesize this alloy. The metal powders were analyzed before and after milling by X-ray diffraction and scanning electron microscopy (SEM). The results obtained by XRD shows the formation only of Mg2Cu phase in short milling time in both compositions. These results show that due to the high impact between milling media, material and control agent can be obtained this alloy easily and fast by mechanical alloying technique.

Open Access Original Research Article

Phytochemical Study of Sacoglottis gabonensis (Baill.) Urb. Isolation of Bioactive Compounds from the Stem Bark

Guy Raymond Feuya Tchouya, Giresse Delphang Nguema Obiang, Jean-bernard Bongui, Jacques Lebibi

Chemical Science International Journal, Page 1-5
DOI: 10.9734/ACSJ/2016/22314

Aims: The main objective of the study was to isolate biomolecules from Sacoglottis gabonensis, and also to identify its antimicrobial active principles.

Study Design: Chromatographic separation of biomolecules from the stem bark extract of              S. gabonensis and spectral analysis of the isolated compounds.

Place and Duration of the Study: Department of Chemistry, Faculty of Science, Scientific and Technical University of Masuku, Box. 223(Potos), Franceville, Gabon, and International Center for Chemical and Biological Sciences, H. E. J. Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan, between January 2014 and March 2015.

Methodology: The stem bark extract of S. gabonensis was fractionated by means of silica gel column chromatography, and the isolated biomolecules characterized through extensive spectroscopic analyses. 

Results: Two bioactive substances, involved in the antimicrobial property of the plant were isolated, and their structures assigned as known compounds, bergenin and gallic acid.

Conclusion: The compound gallic acid was isolated from S. gabonensis by using Column chromatography for the first time. Bergenin and gallic acid can be considered as antimicrobial active principles of S. gabonensis.

Open Access Original Research Article

Structure-toxicity Relationships of Naphthylisoquinoline Derivatives as Antimalarial Agents Using Molecular Descriptors

Zakari Y. Ibrahim, Adamu A. Uzairu, Stephen E. Abechi

Chemical Science International Journal, Page 1-16
DOI: 10.9734/ACSJ/2016/22639

The cytotoxicity data of 46 naphthylisoquinoline derivatives that will inhibit 50% of cell growth (pIC50) were used to develop quantitative structure-activity relationships (QSAR). 433 molecular descriptors was obtained from DFT (B3LYP/6-311+G*) level of calculation for each molecule and used in multiple linear regression (MLR) analysis to generate 4 models, out of which the one with the highest statistical significance having correlation coefficient R = 0.791 and cross validated squared correlation coefficient Q2 = 0.573 was selected as the best model. The QSAR model indicate that the MDE descriptors (MDEC-33) play an important role in the cytotoxicity of naphthylisoquinoline. The accuracy of the proposed MLR model was illustrated using the following evaluation techniques: cross-validation, Y-randomization and external validation on test set. The predictive ability of the model was found to be satisfactory and could be used for designing a similar group of anti-malarial drugs with lower cytotoxicity.

Open Access Original Research Article

Studies of Oxyanion Removal from Aqueous Solution Using Zeolite and HDTMA-Br Surface Modified Organo-Zeolite

Hutaf M. Baker

Chemical Science International Journal, Page 1-14
DOI: 10.9734/ACSJ/2016/22053

In the present study, the Jordanian zeolite was modified with cationic surfactant, hexadecyltrimethylammonium bromide (HDTMA-Br), and this organo-zeolite was used to remove the nitrate ion (oxyanion). Batch experiments were carried out using zeolite at different parameters; isotherms equilibrium models Langmiur, Freundlich, Dubinin-Radushkevich and Redlich-Peterson were investigated at different temperature values 25, 30, 35, 40 and 45°C. Redlich-Peterson, Freundlich and Dubinin-Radushkevich models showed that the experimental equilibrium data followed these models better than that of Langmuir model. The calculated energy  Zeolite and organo-zeolite were used as adsorbents for the investigation of the kinetic studies using column reactor. Kinetic models, a pseudo-second-order, intraparticle diffusion and Elovich were used to analyze the results. The calculated qmax values using second-order model for both organo-zeolite and zeolite are (1.720-2.074) and (0.916-1.274) respectively, the values of qmax for organo-zeolite are higher than that of zeolite. The normalized standard deviation (%SSE) showed a good agreement between the experimental capacity and the calculated one at different temperature values for both zeolite and the organo-zeolite. The intraparticle diffusion model showed deviation from linearity when zeolite is used and showed one line when the adsorbent is organo-zeolite. The calculated activation energies (Ea) in kJ/mol for both zeolite and the organo-zeolite, are 90.7 and 13.7 respectively, the value of the activation energy gives us evidence that the organo-zeolite is better than the zeolite as an adsorbent because it has lower activation energy than the zeolite.

 

Open Access Original Research Article

Synthesis of ZnO Nanoparticles from Zinc Formate and Their Optical Properties

Susmita Boruah, Syeda Mustafiza, Devojit Saikia, Heerok Jyoti Saikia, Partha P. Saikia, Mrinal K. Baruah

Chemical Science International Journal, Page 1-10
DOI: 10.9734/ACSJ/2016/22660

Zinc oxide nanoparticles were successfully synthesized by alkaline precipitation method from zinc formate dihydrate and sodium hydroxide using sodium dodecyl sulphate (SDS) as a surface active agent. In another experiment, the zinc salt was heated at 600°C for comparison with the synthesized ZnO nanoparticles by precipitation method. Defined morphological characteristics of complex nanomaterial such as spherical, nanoflex, dumb-bell like and rod-like shapes have been obtained. The nanoparticles were characterised by X-ray diffraction (XRD). The morphologies of synthesized zinc oxide nanoparticles were determined by scanning electron microscope (SEM). The elemental composition of the nanoparticles was carried out by SEM attached Energy Dispersive X-ray Diffractometer (EDX). Optical properties of prepared ZnO nanoparticles were studied by UV-visible spectrophotometer. It has been found that band gap of the nanoparticles are in the range 3.36 – 3.65 eV and the radii of the particles are in the range 1.48 – 2.73 nm.

Open Access Original Research Article

Integrated Process for -glucan Concentrate from Ganoderma lucidum by Extraction and Micronization

Siti Machmudah, Shoko Kodama, Wahyudiono ., Hideki Kanda, Motonobu Goto

Chemical Science International Journal, Page 1-8
DOI: 10.9734/ACSJ/2016/22842

Hydrothermal treatment is an environmentally friendly technique with a wide range of applications such as extraction, hydrolysis, and wet oxidation of organic compounds. In this work, water under hydrothermal conditions was used to extract b-glucan from Ganoderma lucidum (G. lucidum) at 433 K and 4.0 MPa using a semi-batch system. The extracts were then directly atomized and contacted with a hot inert gas to produce microsphere particles. When nitrogen was used as the inert gas, the moisture evaporated faster than when normal air was used at the same inlet gas temperature. Scanning electron microscopy (SEM) images showed that corrugated particles were obtained, with diameters varying from 3 to 20 microns. The b-glucan content in the particle products was 40 to 45% in weight, approximately.