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107. Global Aurora on Mars During the September 2017 Space Weather Event

Author

Schneider, N. M., primary, Jain, S. K., additional, Deighan, J., additional, Nasr, C. R., additional, Brain, D. A., additional, Larson, D., additional, Lillis, R., additional, Rahmati, Ali, additional, Halekas, J. S., additional, Lee, C. O., additional, Chaffin, M. S., additional, Stiepen, A., additional, Crismani, M., additional, Evans, J. S., additional, Stevens, M. H., additional, Lo, D. Y., additional, McClintock, W. E., additional, Stewart, A. I. F., additional, Yelle, R. V., additional, Clarke, J. T., additional, Holsclaw, G. M., additional, Lefevre, F., additional, Montmessin, F., additional, and Jakosky, B. M., additional

Published
2018
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109. Risk of developing chronic myeloid neoplasms in well-differentiated thyroid cancer patients treated with radioactive iodine

Author

Molenaar, R J, primary, Pleyer, C, additional, Radivoyevitch, T, additional, Sidana, S, additional, Godley, A, additional, Advani, A S, additional, Gerds, A T, additional, Carraway, H E, additional, Kalaycio, M, additional, Nazha, A, additional, Adelstein, D J, additional, Nasr, C, additional, Angelini, D, additional, Maciejewski, J P, additional, Majhail, N, additional, Sekeres, M A, additional, and Mukherjee, S, additional

Published
2017
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114. Synthesis, crystal structure, vibrational, optical properties, and a theoretical study of a new Pb(II) complex with bis(1-methylpiperazine-1,4-diium): [C5H14N2]2PbCl6·3H2O.

Author

Mrad, Mohamed Lahbib, Belhajsalah, Souhir, Abdelbaky, Mohammed Said M., García-Granda, Sergio, Essalah, Khaled, and Ben Nasr, C.

Subjects
OPTICAL properties, CRYSTAL structure, X-ray powder diffraction, X-ray photoelectron spectroscopy, THERMAL analysis
Abstract

An investigation of the solid-state X-ray structure of the new organic–inorganic compound [C5H14N2]2PbCl6·3H2O shows a layered organization of the (PbCl6)4– anions, with (R2NH2)+ groups and water molecules developed in the [001] plane at x = (2n + 1)/4. The crystal structure is stabilized by N − H···Cl, N − H···O, O − H···Cl, O − H···O, and C − H···Cl hydrogen bonds. The powder X-ray diffraction and X-ray photoelectron spectroscopic (XPS) analyses confirm the phase purity of the crystal sample. The intermolecular contacts are quantified using the Hirshfeld surfaces computational method. The major inter-contacts contributing to the Hirshfeld surfaces are H...Cl, H...H, and O...H. The vibrational modes were identified and assigned by IR and Raman spectroscopies. The optical properties were investigated by UV–visible and photoluminescence spectroscopic studies. The compound was characterized by thermal analysis to determine its thermal behavior with respect to the temperature. Finally, X-ray photoelectron spectroscopy analysis is reported for analyzing the surface chemistry of [C5H14N2]2PbCl6·3H2O. [ABSTRACT FROM AUTHOR]

Published
2019
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115. Crystal Structure, Magnetic Properties, and Electrical Characterization of a New Coordination Compound: [CuClO4(C4H6N2O)4H2O]ClO4(C4H6N2O)0.08.

Author

Ben Nasr, M., Kahlaoui, M., Ferenc, W., Cristovao, B., and Ben Nasr, C.

Subjects
CHEMICAL preparations industry, CRYSTAL structure, MOLECULAR structure, MAGNETIC properties, HYDROGEN bonding
Abstract

The chemical preparation and characterization of a novel coordination compound [CuClO4(C4H6N2O)4H2O]ClO4(C4H6N2O)0.08 is reported. The compound crystallizes in the monoclinic space group P21/c with lattice parameters a = 11.2678(5) Å, b = 12.8102(6) Å, c = 19.7250(8) Å, β = 100.3051(15)°, V = 2801.2(2) Å3. The Cu(II) cation is six-coordinated in an elongated distorted octahedral fashion by four N atoms of four 3-amino-5-methylisoxazole ligands, one water oxygen atom, and one perchlorate oxygen atom. In the atomic arrangement, the coordinated and uncoordinated perchlorate anions are grouped in pairs to form anionic layers parallel to the (a, b) plane. A substantial number of H-bonding interactions leads to the formation of an intricate three-dimensional network. The vibrational absorption bands are identified by infrared spectroscopy and the electrical properties are studied by impedance spectroscopy. The DSC analysis agrees with the electrical conductivity results. Magnetic properties are also determined to characterize the complex. [ABSTRACT FROM AUTHOR]

Published
2018
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116. Physico-chemical studies of a novel cadmium(II) coordination compound[(C6H9N2)2CdCl4]0.305H2O

Author

Ben Nasr, M., Zeller, M., Lefebvre, F., and Ben Nasr, C.

Abstract

The crystal structure of the title organic-inorganic hybrid material, [(C6H9N2)2CdCl4]0.305H2O, contains two crystallographically independent but chemically equivalent cadmium complexes with essentially the same geometry (rms deviation of all atoms: 0.152 Å). The metal centers have a 6-coordinated octahedral geometry and both Cd atoms exhibit exact crystallographic inversion symmetry. Crystal packing is stabilized by intermolecular N-H...Cl hydrogen bonds that connect individual zwitter-ionic complexes into a three dimensional lattice, which is further stabilized through p-p stacking interactions between aromatic rings of neighboring complexes, with centroid to centroid distances of 3.4406(14) and 3.7022(13) Å and interplanar separations of 3.299(1) and 3.302(1) Å. Interstitial space is partially filled with water molecules which are connected to the network through O-H...Cl and C-H...O hydrogen bonds. The 13C and 15N CP-MAS NMR spectra are in agreement with the X-ray structure. Four resonance peaks for the C3 carbon atom are observed due to the different environments of the aromatic rings caused by the presence of 0.305 water molecule per unit cell. DFT calculations allow the attribution of the carbon and nitrogen peaks to the different atoms., European Chemical Bulletin, Vol 3, No 4 (2014): European Chemical Bulletin

Published
2014
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119. Synthesis and physico-chemical studies of a novel noncentrosymmetric heptacoordinated cadmium(II) compound containing a tripodal amine, CdCl2[N(C2H6N)3]2

Author

Nasr, M. Ben, Kaabi, K., Silva, P. S. Pereira, Lefebvre, F., Nasr, C. Ben, Nasr, M. Ben, Kaabi, K., Silva, P. S. Pereira, Lefebvre, F., and Nasr, C. Ben

Abstract

A new noncentrosymmetric Cd(II) complex with thetripodal amine tris(2-aminoethyl)amine, CdCl2[N(C2H6N)3]2, has been prepared and characterized by single crystal X-ray diffraction, solid state NMR and IR spectroscopies. In the complex, the Cd(II) ion is surrounded by sevennitrogen atoms. The organic molecule acts as both a tri-and a tetradentate ligand. The cationic complexes are linked to each other forming layers parallel to the (a, b)plan. The Cl- counter ions occupy the cavities created inside these layers. The 13C CP-MAS NMR spectra are in agreement with the X-ray structure. DFT calculations allow the attribution of the carbon peaks to the differentatoms.The vibrational absorption bands were identified by infrared spectroscopy and DFT calculations allowed their attributions.

Published
2014

123. Risk of developing chronic myeloid neoplasms in well-differentiated thyroid cancer patients treated with radioactive iodine

Author

Molenaar, R J, Pleyer, C, Radivoyevitch, T, Sidana, S, Godley, A, Advani, A S, Gerds, A T, Carraway, H E, Kalaycio, M, Nazha, A, Adelstein, D J, Nasr, C, Angelini, D, Maciejewski, J P, Majhail, N, Sekeres, M A, and Mukherjee, S

Abstract

Exposure to ionizing radiation increases the risk of myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN), but such risks are not known in well-differentiated thyroid cancer (WDTC) patients treated with radioactive iodine (RAI). A total of 148 215 WDTC patients were identified from Surveillance, Epidemiology and End Results registries between 1973 and 2014, of whom 54% underwent definitive thyroidectomy and 46% received adjuvant RAI. With a median follow-up of 6.6 years, 77 and 66 WDTC patients developed MDS and MPN, respectively. Excess absolute risks for MDS and MPN from RAI treatment when compared to background rates in the US population were 6.6 and 8.1 cases per 100 000 person-years, respectively. Compared to background population rates, relative risks of developing MDS (3.85 (95% confidence interval, 1.7–7.6); P=0.0005) and MPN (3.13 (1.1–6.8); P=0.012) were significantly elevated in the second and third year following adjuvant RAI therapy, but not after thyroidectomy alone. The increased risk was significantly associated with WDTC size ⩾2 cm or regional disease. Development of MDS was associated with shorter median overall survival in WDTC survivors (10.3 vs 22.5 years; P<0.001). These data suggest that RAI treatment for WDTC is associated with increased risk of MDS with short latency and poor survival.

Published
2018
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137. Bis[4-(dimethyl­amino)­pyridinium] tetra­chloridozincate

Author

R. Kefi, Ben Nasr C, Matthias Zeller, and Frédéric Lefebvre

Subjects
Metal-Organic Papers, biology, 010405 organic chemistry, Chemistry, Hydrogen bond, Stacking, General Chemistry, 010402 general chemistry, Condensed Matter Physics, biology.organism_classification, Bioinformatics, 01 natural sciences, 0104 chemical sciences, 3. Good health, chemistry.chemical_compound, Crystallography, Tetra, General Materials Science, Pyridinium
Abstract

In the title compound, (C(7)H(11)N(2))(2)[ZnCl(4)], [ZnCl(4)](2-) anions and 4-(dimethyl-amino)-pyridinium cations are held together by various inter-molecular inter-actions including Coulombic attraction, hydrogen bonding and π-π stacking inter-actions. Three Cl atoms of the [ZnCl(4)](2-) tetra-hedron act as acceptors in N-H⋯Cl hydrogen bonds. The hydrogen bonds, both of which are bifurcated, lead to the formation of a three-dimensional network. Within the network, inter-molecular π-π stacking inter-actions with a centroid-centroid distance of 3.5911 (7) Å arrange the 4-(dimethyl-amino)-pyridinium cations into anti-parallel dimers.

Published
2011

140. Furfurylammonium chloridozincophosphate

Author

Kamel Kaabi, Ben Nasr C, Frédéric Lefebvre, El Glaoui M, and Erwann Jeanneau

Subjects
lcsh:Chemistry, Metal-Organic Papers, chemistry.chemical_compound, lcsh:QD1-999, Hydrogen bond, Chemistry, Polymer chemistry, General Materials Science, Ammonium, General Chemistry, Condensed Matter Physics, Bioinformatics
Abstract

In the title compound, [ZnCl(HPO4)](C5H8NO), polymeric inorganic layers constructed from ZnO3Cl and PO4 tetrahedra are linked by O atoms: O—H...O hydrogen bonds occur within the layers. The organic cations occupy the interlayer regions and interact with the layers by way of N—H...O, N—H...Cl, and C—H...Cl hydrogen bonds.

Published
2010

144. Métastases cérébrales : quel traitement optimal ?

Author

Khanchel, F., primary, Bahri, M., additional, Fehri, R., additional, Kochbati, L., additional, Nasr, C., additional, Hentati, D., additional, Gargouri, W., additional, Frikha, H., additional, Ayoub, W. Ben, additional, and Maalej, M., additional

Published
2008
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