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Na3MP3O10·12H2O (M = Co, Ni): Crystal Structure and IR Spectroscopy
Khalil Azzaoui,Rachid Essehli,El Miloud Mejdoubi,Brahim El Bali,Michal Dusek,Karla Fejfarova
International Journal of Inorganic Chemistry , 2012, DOI: 10.1155/2012/702471
Abstract: Two new dodecahydrate trisodium triphosphates Na3MP3O10·12H2O (M = Co (1), Ni (2)) were synthesized using a wet chemistry route and characterized by X-ray diffraction and FT-IR spectroscopy. They are isotypic, monoclinic (P21/ , ), with pseudoorthorhombic unit cell parameters (？,°): ( (4), (2), (4), (2), for (1) and (3), (2), (3), (16) for (2)). Values of / are 0.0267/0.0738 and 0.0284/0.0907, respectively, for (1) and (2). Both compounds were found to be systematically twinned by 180° rotation around . Their frameworks are made by slabs parallel to plane, resulting from the cohesion of two kinds of metallic chains. IR spectrum confirms the presence of characteristic bands from P3O10 phosphate group. 1. Introduction Phosphates containing polyanions ( and 2) have been intensively investigated during the last few decades because of their applications in different fields: solid electrolytes for energy stockage, Li-ion batteries, ceramics, luminescence, and magnetism [1]. Kanonerovite, Na3MnP3O10·12H2O, is a natural triphosphate mineral [2]; few other synthetic triphosphates have been reported in the literature: Na3CuP3O10·12H2O [3], LiZn2P3O10·8H2O [4], NaZn2P3O10·9H2O [5], and Na3CdP3O10·12H2O [6]. Anhydrous triphosphates have been also studied: LiFe2P3O10 [7], LiM2P3O10, M = Co and Ni [8, 9], RbBe2P3O10 [10], Cs2MP3O10 (M = Ga, Al, Cr) [11]. These latter ternary phosphates, with the frameworks consisting in associated [PO4] and [MO6], are efficiently used for waste storage hosts [12]. We deal in the present work with the synthesis and structural study of two new hydrated phases: Na3MP3O10·12H2O, M = Co (1) and Ni (2). 2. Experimental 2.1. Synthesis The title compounds Na3M(P3O10)·12H2O (M = Co (1), Ni (2)) were obtained by mixing two solutions made of following reactants, each dissolved in 10？mL distilled water: Na5P3O10 (0.3219？g) and, respectively, CoCl2·6H2O (0.2378？g) (1) and NiCl2·6H2O (0.2375？g) (2). The mixtures were stirred for 1？h and then allowed to stand at room temperature. After 2 weeks pink crystals of compound (1) and light green crystals of compound (2) were collected by filtration. The crystals were washed with a water-ethanol (80？:？20？v/v) mixture. 2.2. Single Crystal Study The X-ray diffraction data for (1) and (2) were collected in a four-circles diffractometer Gemini of Oxford Diffraction (now Agilent Technologies), using graphite monochromatized CuKα radiation ( ？？) collimated by mirrors, detector Atlas. The intensity data were corrected for Lorentz and polarization effects. A numerical absorption correction based on the crystal
Attempt at the determination of aluminum nitrate LD50 and the study of its neurotoxicological effect in Wistar rat
FZ Azzaoui
Biology and Medicine , 2012,
Abstract: Values of oral lethal dose of aluminum (Al) nitrate are extremely different and rare in the literature. The study is an attempt to determine the oral LD50 of aluminum nitrate in the Wistar rats and to measure the effect of the high doses of this aluminum compound on rats’ different organs, on acetylcholinesterase (AChE) activity, and on acetylcholine (ACh) levels in the hippocampus. Four groups of male Wistar rats are used (n = 28). The treated groups receive three doses of aluminum nitrate (Al1 = 2,500 mg/kg, Al2 = 3,500 mg/kg, and Al3 = 4,500 mg/kg) once by gavage, while control rats receive tap water. All rats are examined twice daily for mortality and impairment during the 2-week experiment. The bodyweight (BW) is measured at the beginning and at the end of the experiment. Dissection is realized for each dyed rat and the dosage of AChE activity and ACh levels isrealized at the end of the experiment by colorimetric method. The obtained results show that the higher dose (Al3) kills 30% of the rats under study and causes spleens’ dark discoloration in the dyed rats. Both Al2 and Al3decrease significantly the spleen weight (p < 0.01) and AChE activity (p < 0.01), but increase significantly the ACh levels (p < 0.01 and p < 0.001, respectively), in hippocampus of rats. Even if the lethal dose of aluminum nitrate is not reached, the effect of the high acute doses on viscera and cholinergic system is demonstrated.
Spectral representation of some non stationary alpha-stable processes
Nourddine Azzaoui
Mathematics , 2008,
Abstract: In this paper, we give a new covariation spectral representation of some non stationary symmetric $\alpha$-stable processes (S$\alpha$S). This representation is based on a weaker covariation pseudo additivity condition which is more general than the condition of independence. This work can be seen as a generalization of the covariation spectral representation of processes expressed as stochastic integrals with respect to independent increments S$\alpha$S processes (see Cambanis (1983)) or with respect to the general concept of independently scattered S$\alpha$S measures (Samorodnitsky and Taqqu 1994). Relying on this result we investigate the non stationarity structure of some harmonisable S$\alpha$S processes especially those having periodic or almost-periodic covariation functions.
Non Linear Magnetic Hysteresis Modelling by Finite Volume Method for Jiles-Atherton Model Optimizing by a Genetic Algorithm  [PDF]
Seddik Azzaoui, Kamel Srairi, Mohamed El Hachemi Benbouzid
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2011, DOI: 10.4236/jemaa.2011.36032
Abstract: This paper describes a generalization methodology for nonlinear magnetic field calculation applied on two-dimensional (2-D) finite Volume geometry by incorporating a Jiles-Atherton scalar hysteresis model. The scheme is based upon the definition of modified governing equation derived from Maxwell’s equations considered the magnetization M. This paper shows how to extract optimal parameters for the Jiles-Atherton model of hysteresis by a real coded genetic algorithm approach. The parameters identification is performed by minimizing the mean squared error between experimental and simulated magnetic field curves. The calculated results are validated by experiences performed in an SST’s frame.
Penggunaan Formula Mineral Lokal dalam Ransum Ayam Petelur
Khalil
Media Peternakan , 2010,
Abstract: A mineral formula composed of three locally available materials: limestone originated from Bukit Kamang of West Sumatra, freshwater oyster shell and bone meal and fortified with micro minerals of Cu, Zn and I was investigated as mineral supplement for diet of laying hens. The experimental diets were: P0 (diet contained of 6% commercial mineral), P1 (diet contained of 6% local mineral), P2 (diet contained of 6% Bukit Kamangs’ limestone) and P3 (diet contained of 6% fresh water oyster shell meal). The total of four experimental diets was then fed to 120 laying hens. The hens were divided into 3 groups based on body weight: heavy, medium and light. Each group was subdivided into 4 subgroups in accordance with number of treatments, so that each treatment consisted of 3 replicates containing of 10 hens. Parameters measured included: feed intake, hen-day egg production, feed conversion ratio (FCR), eggshell quality, mineral retention and mineral composition of tibia bone. Data were subjected to statistical analysis using variance analysis in a completely block design with 4 treatments and 3 blocks as replicates The results showed that the egg weight and eggshell qualities were found not significantly difference, but different mineral sources gave significant effect on egg production and bone mineralization. The laying performances and tibia bone weight of chickens fed diet mixed with the local mineral formula were found not significantly different with those fed diet mixed with commercial formula, but significantly better (P<0.05) than those of fed diet mixed with only limestone or oyster shell. Hens fed with diet mixed with Bukit Kamangs’ limestone showed better performances and heavier tibia bone than those fed with diet mixed with oyster shell. It was concluded that the local mineral formula could be used as sole mineral source for laying hens. The nutritive value of Bukit Kamangs’ limestone was better than that of fresh water oyster shell.
Pengaruh Penggilingan dan Pembakaran terhadap Kandungan Mineral dan Sifat Fisik Kulit Pensi (Corbiculla Sp) untuk Pakan
Khalil
Media Peternakan , 2006,
Abstract: An experiment was conducted to determine the percentage of rate, nutrient contents and physical properties of grinding and roasting products of freshwater mussel shell. Fresh mussel samples were collected from four different lakes in West Sumatra: Maninjau, Singkarak, Danau Diatas and Danau Dibawah. The samples of about 3 kg each were processed to separate the shell and their body content. The shells were then dried and processed to produce three different products: raw coarse ground, raw fine ground and roasted fine ground. Parameters measured included: percent rate of meal, the content of DM, ash, Ca and P, and physical properties (angle of response, bulk and compacted bulk densities and specific density). The results showed that grinding and roasting gave no significant effect on specific density and mineral content of the meal product. The rate of meal product and bulk density decreased, while angle of response and compacted bulk density increased significantly. It was concluded that both roasting and grinding could not improve both nutrient content and physical properties of freshwater mussel shell.
Respons Ayam Kampung terhadap Penambahan Kalsium Asal Siput (Lymnae Sp) dan Kerang (Corbiculla molktiana) pada Kondisi Ransum Miskin Fosfor
Khalil
Media Peternakan , 2006,
Abstract: The objectives of this present investigation were to evaluate effects of using shell of freshwater snail as major source of calcium in the diets on performance and bone mineralization of growing native chicks (1-12 weeks of age). There were four dietary treatments. The first was a basal diet (negative control) containing 0.5 % bone meal, but deficient in phosphor. Three other diets which were relatively the same in composition as that of basal diet, but one supplemented with 2.5 % oyster shell (positive control) and two with 2.5% shell of freshwater snail obtained from two different water bodies: lake and rice field, respectively. One hundred birds of native chicken were divided into four groups of treatments with five replicates with 5 birds each and offered experimental diets for 12 weeks. Parameters measured included: body weight gain, feed intake, feed conversion ratio (FCR), weight of tibia bone and their ash and mineral (Ca and P) composition and retention. The chicks fed on diets containing shell of freshwater snails showed no significantly difference in body weight gain, feed intake and FCR with those fed on diet containing oyster shell, but significantly lower body weight gain than those fed on basal diet containing only bone meal. Feeding of diets supplemented with shell of snails and oyster decreased significantly the body weight gain. However, no significantly difference was observed in the weight and content of ash, Ca and P of tibia bone.
Quantum Statistical Properties of the Interactions of Atom-Field Entanglement between Conducting Plates  [PDF]
Eied Khalil
Journal of Modern Physics (JMP) , 2011, DOI: 10.4236/jmp.2011.27085
Abstract: The electromagnetic field inside perfectly conducting parallel plates interacting with two-level atom is investigated. The cavity modes are firstly quantized, allowing the effective Hamiltonian to be evaluated for an electric dipole located at an arbitrary point. Some statistical aspect of this effective Hamiltonian such as the temporal evolution of the atomic inversion and the von Neuman entropy are presented. Theses aspects are sensitive to the changes of the distance between the two plates, which control the number of the propagating of the cavity modes.
The Accuracy of GIS Tools for Transforming Assumed Total Station Surveys to Real World Coordinates  [PDF]
Ragab Khalil
Journal of Geographic Information System (JGIS) , 2013, DOI: 10.4236/jgis.2013.55045
Abstract: Most surveying works for mapping or GIS applications are performed with total station. Due to the remote nature of many of the sites surveyed, the surveys are often done in unprojected, local, assumed coordinate systems. However, without the survey data projected in real world coordinates, the range of possible analyses is limited and the value of existing imagery, elevation models, and hydrologic layers cannot be exploited. This requires a transformation from the local assumed to the real world coordinate systems. There are various built-in and add-in tools to perform transformations through GIS programs. This paper studies the effect of using Georeferencing tool, Spatial Adjustment tool (Affine and similarity) and CHaMP tool on the precision and relative accuracy of total station survey. This transformation requires real-world coordinates of at least two control points, which can be collected from different sources. This paper also studies the effect of using geodetic GPS, hand-held GPS, Google Earth (GE) and Bing Basemaps as sources for control points on the precision and relative accuracy of total station survey. These effects have been tested by using 111 points covered area of 60,000 m2and the results have shown that the CHaMP tool is the best for preserving the relative accuracy of the transformed points. The Georeferencing and spatial adjustment (similarity) tools give the same results and their accuracy are between 1/1000 and 1/300 depending on the source of control points. The results have also shown that the cornerstone to preserve the precision and relative accuracy of the transformed coordinates is the relative position of the control points despite their source.
Portfolio as a Stimulus for Improving the Work of Teacher Educators: An Experience at a College in the Arab Sector  [PDF]
Mahmood Khalil
Creative Education (CE) , 2014, DOI: 10.4236/ce.2014.517177
Abstract: The present article examines the contribution of building a portfolio to the professional development of teacher educators, and the effectiveness of their progress within the organized framework. The results of long-time research that was carried out in a college for teachers’ education show the contribution of the derivative works that contain reflection and accompanies reflective thinking meetings for professional progress of teacher educators; for strengthening their motivation; for improving their level of education and ensuring its quality; to develop their involvement in the duty they are fulfilling and for a annual and future planning cultivation. Moral education, values and attitudes via acquiring knowledge in science content knowledge as Dreyfus (1995) emphasized that “biological knowledge is a prerequisite for the development of students’ values and attitudes”. Science knowledge role is not only for academic achievement and mastery of cognitive and metacognitive skills, but to educate students on the affective domain being active in the community life based on moral and ethical values, and positive attitudes toward societal issues, like social justice, preservation of the environment and peace, the last two being addressed due to the fact of having a mutual impact connection in one of the STS learning units presented.
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