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We are very happy to announce that from 17th July 2012, Mrs. Najmeh Samadi has joined the team of Elixir Editorial Advisory Board. She will carry a special responsibility for dealing with manuscripts based on Soil Science. Mrs. Najmeh Samadi is currently associated with Soil Surveying and Mapping Laboratory, Faculty of Agriculture, Islamic Azad University, Khorasgan Branch, Isfahan. The appointment of Mrs. Najmeh Samadi as member Editorial Advisory Board strengthens the links and will make it easier for prospective authors to establish contact with the journal. Please send any expressions of interest to chiefeditor@elixirjournal.org. Sincerely Editor-in-Chief

Plant extracts are excessively used as corrosion inhibitors. Plant extracts contain a variety of organic compounds such as alkaloids, flavonoids, tannins, cellulose and polycyclic compounds. The compounds with hetero atoms-N, O, S, P coordinate with (corroding) metal atom or ion consequently forming a protective layer on the metal surface, that prevents corrosion. These serve as cheaper, readily available, renewable and environmentally benign alternatives to costly and hazardous corrosion inhibitors .This study reports screening of phytoconstituents and also reports the influence of the addition of Pongamia pinnata (L.) Pierre leaves extract on the corrosion inhibition of mild steel in 2.0 M H2SO4 solution using the Mylius thermometric technique. Results of the study revealed that Pongamia pinnata (L.) Pierre. leaves act as corrosion inhibitor for mild steel in the acidic medium. The addition of 0.1 M potassium chloride, potassium bromide and potassium iodide to the inhibitor enhanced the inhibition efficiency. The order of reactivity of halide ions is of the order KI > KBr > KCl. The inhibition efficiency increased 58 % to 78 % at a concentration of 0.1 M KI and 5.0 % of inhibitor concentration. The values of adsorption of Pongamia pinnata (L.) Pierre leaves extract onto the mild steel surface show that the process is spontaneous.

Set partitioning problems are known to be NP-hard, thus it requires massive amounts of times and efforts to solve them using linear programming and traditional algorithms. This study proposes to use a scatter search algorithm coupled with a tabu search algorithm for such problems. The proposed algorithm is applied to the 3rd level football leagues in Turkey. 54 teams competing in the league are divided into three categories randomly by the Turkish Football Federation. The proposed algorithm in this study aims to set up these categories with the goal of minimizing the total amount of travelling, thus cost and time throughout the league. Experimental results show that the proposed algorithm reduces the total travelling by a significant amount of 56%.

We are very happy to announce that from 7th June 2012, Prof. Raka Kamal has joined the team of Elixir Editorial Advisory Board. She will carry a special responsibility for dealing with manuscripts based on Botany and Biotechnology. Prof. Raka Kamal is currently associated with Department of Botany, University of Rajasthan, Jaipur-302004, India. The appointment of Prof. Raka Kamal as member Editorial Advisory Board strengthens the links and will make it easier for prospective authors to establish contact with the journal. Please send any expressions of interest to chiefeditor@elixirjournal.org. Sincerely Editor-in-Chief

In this paper, a medical image watermarking algorithm based on contourlet is proposed. Medical image watermarking is a special subcategory of image watermarking in the sense that images have special requirements. Watermarked medical images should not differ perceptually from their original counterparts because clinical reading of images must not be affected. Watermarking techniques based on wavelet transform are reported in many literatures but robustness and security using contourlet are better when compared to wavelet transform. The main challenge in exploring geometry in images comes from the discrete nature of the data. In this paper, original image is decomposed to two level using contourlet and the watermark is embedded in the resultant sub-bands. Sub-band selection is based on the value of Peak Signal to Noise Ratio (PSNR) that is calculated between watermarked and original image. To extract the watermark, Kernel ICA is used and it has a novel characteristic is that it does not require the transformation process to extract the watermark. Simulation results show that proposed scheme is robust against attacks such as Salt and Pepper noise, Median filtering and rotation. The performance measures like PSNR and Similarity measure are evaluated and compared with Discrete Wavelet Transform (DWT) to prove the robustness of the scheme. Simulations are carried out using Matlab Software.

Reactive Distillation (RD) is the combination of chemical reaction and distillative product separation in single piece of equipment, offers a number of specific advantages over conventional sequential approach of reaction followed by distillation or other separation techniques. The experimental part includes RD experiments in laboratory scale, carefully evaluated database for describing chemical reaction and phase equilibria. The iso-amyl acetate synthesis is also carried out in a packed bed RD column operated in batch and continuous modes. This paper describes an investigation into experimental and simulation work of the heterogeneous esterification of acetic acid with iso-amyl alcohol, catalyzed by an acidic cation –exchange resin. The effects of the variables such as the reflux ratio, vapour rate and feed flow rate on iso-amyl acetate synthesis are studied experimentally. The simulations are based on the equilibrium-stage model approach. The simulation studies are performed in Aspen Plus and MATLAB. Finally results of sensitivity studies using Aspen plus are presented to show the optimum performance of RD column.

The synthesis of various substituted 4-methoxy-1H-quinolin-2-thiones from various substituted aniline with malonicacid, phosphorous-oxychloride, sodium methoxide glacial acetic acid and thiourea under different conditions is described. The title compounds were synthesized from four steps; the first step involved the synthesis of substituted 2, 4-dichloro quinoline from aniline (substituted), with malonicacid and phosphorous-oxychloride. In the second step, the substituted 2, 4 Dichloro compound was heated with freshly prepared methanolic sodium methoxide solution to give 2, 4-dimethoxy quinoline compounds, it was then refluxed with glacial acetic acid and hydrochloric acid to get the substituted 4-methoxy-1H-quinolin-2-one. The final steps involves with an objective of introducing a chloro in the position 2 of the quinolone system, the substituted 4-methoxy-1H-quinolin-2-one was refluxed with distilled Pocl3 chloroform. The substituted 2-chloro-4-methoxy quinoline was then refluxed with thiourea and alcohol to get the titled compounds. The purity of the synthesized compound was judged by their C, H and N analysis and the structure was analyzed on the basics of Mass, FT-IR, and 1H NMR.

Metal oxides play a very important role in many areas of chemistry, physics and materials science.  The metal elements are able to form a large diversity of oxide compounds.  These can adopt a vast number of structural geometries with an electronic structure that can exhibit metallic, semiconductor or insulator character. In technological applications, oxides are used in the fabrication of microelectronic circuits, sensors, Piezo-electric devices, fuel cells, coatings for the passivation of surfaces against corrosion, and as catalysts. In the emerging field of nanotechnology, a goal is to make nanostructures or nanoarrays with special properties with respect to those of bulk or single particle species.  Oxide nanoparticles can exhibit unique physical and chemical properties due to their limited size and a high density of corner or edge surface sites. Amomg the metal oxides,  Magnesium oxide (MgO) is widely used in the chemical industry as a scrubber for air pollutant gases (CO₂, NO_X, SO_X) and as a catalyst support.  It exhibits a rock salt structure like oxides of other alkaline earth metals.  The non-polar (100) face is by far the most stable surface,  and particles of MgO usually display a cubic shape. For example, when Mg metal is burned in air or oxygen, the MgO smoke particles that are formed are almost perfect cubes having (100) faces.

An attempt has been made to prepare mixed metal oxide (MMO) nanoparticles of Zr, Al, Si by sol-gel route from commercially available zircon flour, fly ash and aluminum metal respectively. Isopropoxides of zirconium and silicon from zircon and isopropoxides of alumino silicates from fly ash were prepared in separate experiments by alkoxylation of corresponding fluorides/fluoro acids that were obtained by digesting separately, zircon and fly ash respectively in hydrofluoric acid. Aluminum isopropoxides was prepared by alkolxylation of sodium aluminate that was prepared by dissolving aluminum metal in sodium hydroxide. MMO nanoparticles was obtained by neutralizing the isopropoxides of zircon and fly ash (1:1, v/v) respectively with aluminum isopropoxide. SEM and TEM analysis of the MMO nanoparticles revealed that the average size of primary particle is in the range of 2nm to 4 nm. EDAX of MMO nanoparticles indicated presence of aluminum (Al), zirconium (Zr) and silicon (Si) and oxygen (O).Compressive strength of poly(methyl methacrylate) [PMMA] reinforced with MMO nanoparticles was found to be superior to that of neat PMMA and PMMA composites reinforced with MMO micron particles.

The main objective of the research presented herein was to developed poly(dodecyl phenol formaldehyde)-b-poly(oxypropylene) block copolymer for asphaltene precipitation problem and performance of some asphaltene inhibitors\dispersant for a heavy crude oil provided by the Hossia crude oil (Ras Gharib – Egyptian Eastern desert). The dispersants/inhibitors was synthesized in tow steps; 1) synthesis of poly(dodecyl phenol formaldehyde) resin (PDPF) at three different molecular weights (1936, 4047 and 8092) namely PDPF1, PDPF2 and PDPF3 respectively; 2) propoxylation of the prepared compounds to produce PDPF1-b-POP, PDPF2-b-POP and PDPF3-b-POP has molecular weight (3096, 5179 and 9202) respectively. All of the synthesized compounds were evaluated as asphaltene inhibitors/dispersants at 100, 500 and 1000 ppm using UV spectrophotometer. The molecular weights were determined by GPC. The chemical structure of the prepared compounds was confirmed by IR and H1NMR. The crude oil was analyzed by GC. The results also revealed distinct inhibition of asphaltene precipitation in crude oils.