Synthesis And Characterization Of Two New Antimony Phosphates Co0,5alsb(PO4)3 And Mg0,5fesb(PO4)3

Two new antimony phosphates Co0,5AlSb(PO4)3 and Mg0,5FeSb(PO4)3 were synthesized for the first time by the solid-state reaction method. Their crystal structures have been refined at room temperature from X-ray powder diffraction data using Rietveld method. Co0,5AlSb(PO4)3 crystallizes in the space group R-3c (N°167) (ah = 8.23±0.01Ǻ, ch = 21.94±0.02Ǻ). Mg0,5FeSb(PO4)3 crystallizes in the monoclinic space group P21/n (N°14) (am =11.54 Ǻ, bm = 8.83± 0.02 Ǻ, cm = 8.39± 0.01 Ǻ, β = 96.67°± 0.09). Raman and infrared spectra were recorded and assignments of the stretching and bending vibrations of the PO43- tetrahedra were made. The number of the peaks observed is in good agreement with that predicted by the factor group analysis of the R-3c et P21/n space group respectively. Vibrational spectral studies of two antimony phosphates were collected in-situ at room-pressure and at elevated temperatures, up to 430 oC. At elevated temperatures in air, Mg0,5FeSb(PO4)3 seems to be stable, but Co0,5AlSb(PO4)3 show a transition at 380°C and decomposes at 930°C. This result has been confirmed by differential scanning calorimetric study (DSC).Two new antimony phosphates Co0,5AlSb(PO4)3 and Mg0,5FeSb(PO4)3 were synthesized for the first time by the solid-state reaction method. Their crystal structures have been refined at room temperature from X-ray powder diffraction data using Rietveld method. Co0,5AlSb(PO4)3 crystallizes in the space group R-3c (N°167) (ah = 8.23±0.01Ǻ, ch = 21.94±0.02Ǻ). Mg0,5FeSb(PO4)3 crystallizes in the monoclinic space group P21/n (N°14) (am =11.54 Ǻ, bm = 8.83± 0.02 Ǻ, cm = 8.39± 0.01 Ǻ, β = 96.67°± 0.09). Raman and infrared spectra were recorded and assignments of the stretching and bending vibrations of the PO43- tetrahedra were made. The number of the peaks observed is in good agreement with that predicted by the factor group analysis of the R-3c et P21/n space group respectively. Vibrational spectral studies of two antimony phosphates were collected in-situ at room-pressure and at elevated temperatures, up to 430 oC. At elevated temperatures in air, Mg0,5FeSb(PO4)3 seems to be stable, but Co0,5AlSb(PO4)3 show a transition at 380°C and decomposes at 930°C. This result has been confirmed by differential scanning calorimetric study (DSC)

Effects of Lizardite Addition on Technological Properties of Forsterite-monticellite Rich Ceramics Prepared from Natural Magnesite and Dolomite

Lizardite rich peridotite has never been used to prepare ceramic specimens, especially in Morocco. For this raison, potential use of naturally abundant lazirditic material from the Rif domain, as a supply for ceramic industry, has been evaluated. The effects of lizardite addition to magnesite and dolomite mixtures on the thermomechanical properties of the calcined ceramics were also detailed. To achieve this target, natural lizardite, magnesite and dolomite samples were collected in ultrabasic Beni Bousra massif. Those raw samples were used for the synthesis of a forsterite-monticellite rich ceramics. Both raw and sintered samples were characterized by x-ray diffraction, scanning electron microscope and fourier transform infrared. The obtained results showed that both magnesite and dolomite were mainly composed of MgCO3 and CaCO3. In contrast, lizardite sample showed high amounts of SiO2, MgO and Fe2O3. An increased amount of lizardite in the initial mixtures enhanced mechanical and dimensional properties of the prepared ceramic specimens, and subsequently, the production of ceramics with the required technological properties. Thus, the preparation of Moroccan lizardite-based ceramics is technically feasible, economically justifiable and socially desirable due to the contribution to the economic growth of the raw materials sector, especially ceramic industry

Conception de prothèse surcorrigée pour arthroplastie totale de l’épaule

L’arthrose est une maladie se traduisant par une détérioration progressive du cartilage articulaire. Dans certains cas avancés, cette dégradation peut résulter en une destruction totale du cartilage, contraignant les os à frotter les uns contre les autres. Les personnes atteintes présentent des douleurs articulaires et leur mobilité peut être affectée [1]. Cette maladie peut toucher plusieurs articulations telles que les hanches, les genoux, les doigts ou les épaules. Les causes de l’arthrose de l’épaule sont multiples : instabilité chronique, fracture de l’humérus ou encore rupture de la coiffe des rotateurs. Il existe trois types d’arthrose de l’épaule. Le type A correspond à une érosion symétrique de la glène sans subluxation tandis que le type C désigne une dysplasie sans usure [2]. L’attention est portée ici sur le type B pour lequel l’usure du cartilage apparaît de manière asymétrique, le plus souvent postérieurement. Suivant le degré de détérioration des articulations, l’arthroplastie peut consister à retirer l’articulation malade sans poser de prothèse, sinon à remplacer une partie ou la totalité de l’articulation par une prothèse [3], comme dans le cas de ce projet. Néanmoins, l’arthroplastie totale de l’épaule chez des patients de type B présente des risques post-opératoires de subluxation gléno-humérale. L’implantation d’une prothèse asymétrique spécifique à la morphologie du patient peut être une solution à ce problème. En effet, grâce à la combinaison des images CT de la scapula de chaque patient, du logiciel CAD et d’analyse par éléments finis, il est possible de choisir une surcorrection de la prothèse permettant d’obtenir une répartition des efforts minimisant la subluxation. Ce projet de Bachelor se focalisera sur la conception de deux prothèses surcorrigées uniques, destinées à deux patients de type B, en veillant à obtenir une meilleure répartition des efforts au sein de la scapula et une subluxation plus faible

Mitä jos... -musiikkivideon suunnittelu ja toteutus

Opinnäytetyössä tarkastellaan ensikertalaisen tekemää musiikkivideoprojektia ammattilaisten musiikkivideon tekemiseen. Toimin teososassa käsikirjoittajana, ohjaajana ja tuottajana. Työssä kerrotaan musiikkivideon historiasta ja kehityksestä maailmalla ja Suomessa lyhyesti. Käydään koko musiikkivideon tuotantokaari kappaleen valinnasta, käsikirjoituksesta, kuvakerronnan suunnittelusta, työryhmän ja esiintyjien valitsemisesta aina kuvauspäiviin ja jälkikäsittelyyn. Jokaista eri tuotantovaihetta verrataan ammattilaisten musiikkivideon tekemiseen. Pohditaan, miten saatiin tehtyä koko tuotantokaaren osa-alueet ammattimaisesti, vaikka budjetin olemattomuus asetti haasteita prosessin tekemiselle. Musiikkivideon tarkoitus on promotoida artistia tai yhtyettä ja luoda heille jonkinlainen imago. Artistin tyylin ratkaisee lähinnä musiikki, jollaista hän esittää. Työ vertailee erilaisia musiikkivideotyylejä ja pohtii, miksi kyseisessä musiikkivideossa oli valittu juuri tarinallinen tyyli. Tutkitaan myös miten kuvaussuunnittelu onnistui musiikkivideon tarinan näkökulmasta. Vaihe vaiheelta käydään läpi kuvauspäivien tapahtumat. Kerrotaan, millaisia ongelmia prosessi tuotti ja miten ne saatiin ratkaistua. - Opinnäytetyössä on liitteenä musiikkivideon käsikirjoitus, kuvausaikataulu ja osa kuvakäsikirjoituksesta. - Opinnäytetyöhön kuuluu teososa, musiikkivideo Mitä jos..

Review on the elaboration and characterization of ceramics refractories based on magnesite and dolomite

One of the most important elements of furnaces, boilers and other heating units is the structure (lining), usually made of silica–alumina, basic or special refractories. The basic refractories are materials that are increasingly in demand and whose manufacturing involves necessarily the use of MgO and CaO. In this article, the description and characterization of magnesite (MgCO3) and dolomite (Mg,Ca(CO3)2) and their contribution in industrial ceramics-refractories have been reviewed

Sorption of Cd(II), Ni(II) and Zn(II) on natural, sodium-, and acid-modified clinoptilolite-rich tuff

Sorption of Cd2+, Ni2+and Zn2+ions on natural (ZPCli), sodium modified (ZPCliNa) and acid modified (ZPCliH) zeolites have been investigated in function of the contact time, pH, and metal concentration by the batch technique. The characterization of ZPCIi, ZPCliNa, and ZPCliH materials was performed using X-ray powder diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques. The surface area (BET) and the pHpzcwere also determined. The pH in the point of the zero charge of ZPCli, ZPCliNa, and ZPCliH zeolites was 8.25, 8.00, and 2.05, respectively. The kinetic sorption data for ZPCli, ZPCliNa and ZPCliH were well fitted to the pseudo-second order model (R2> 0.99). The linear model described the Cd, Ni and Zn sorption isotherms for ZPCliH, while for ZPCliNa and ZPCliH it was the Freundlich model. The unmodified and modified zeolitic materials showed the highest sorption capacity for Cd2+, lower for Zn2+ and Ni2+