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Synthesis, crystal structure, magnetic properties and second harmonic generation of a new noncentrosymmetric coordination compound：Triaqua(4-amino-6-methoxypyrimidine) cuprate(Ⅱ)sulfate

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Chinese Chemical Letters 2016年第6期27卷 896-900页

作者： Mahjouba ben nasr Kamel Kaabi Matthias Zeller Wataru Fujita Pedro Sidónio Pereira da Silva cherif ben nasr Laboratoire de Chimie des Materiaux Universite de Carthage Facultedes Sciences de Bizerte 7021 Zarzouna Tunisia Department of Chemistry Youngstown State University One University Plaza Youngstown OH 44555-3663 USA Graduate School of Natural Science Nagoya City University Yamanohata Mizuho-cho Mizuho-ku Nagoya 467-8501 Japan CFisUC Department of Physics University of Coimbra 3004-516 Coimbra Portugal

The chemical preparation, crystal structure and infrared spectroscopic characterization of the triaqua（4-amino-6-methoxypyrimidine） cuprate（II） sulfate, [Cu（C5H7N3）（H2O）3]SO4, is reported. The compound crystallizes in the noncentrosymmetric orthorhombic space group P212121 with lattice parameters a = 7.9025（3）, b = 11.1189（4）, c = 12.9720（4） , V = 1139.81（7） ~3 and Z = 4. The Cu（II） cation is fivecoordinated, in an early half-way between square pyramidal and trigonal bipyramidal fashion, by two nitrogen atoms of the 4-amino-6-methoxypyrimidine ligand and three water oxygen atoms. In the atomic arrangement, the organic ligands and the 5-connected Cu centers are linked with each other to give a 1-D corrugated hybrid chain running along the b-axis direction. The chains are interconnected by the SO4^（2-） anions via O–H...O, O–H...S, C–H...O and N–H...O hydrogen bonds to form layers spreading parallel to the（011） plane. The vibrational absorption bands were identified by infrared spectroscopy. Quantitative measurements of the second harmonic generation（SHG） of a powdered sample at 1064 nm were performed and a relative efficiency of 5.2 times the KDP standard was observed. Magnetic properties were also defined to characterize the complex. Magnetic measurements revealed that this material had a onedimensional antiferromagnetic character. The magnetic parameters were g = 2.11 and 2J/k B = -36 K.

关键词： Square pyramid Cu(II) complex X-ray diffraction Magnetic properties Second harmonic generation

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Synthesis, crystal structure and characterization of a new octane-1,8-diammonium bis(dihydrogenmonophosphate)

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Open Journal of Inorganic Chemistry 2011年第1期1卷 1-8页

作者： Mohamed Lahbib Mrad Salah Ammar Valeria Ferretti Mohamed Rzaigui cherif ben nasr 不详

The synthesis and the structure of a new [H3N-(CH2)8-NH3][H2PO4]2 is described. This compound crystallizes in the orthorhombic system, with the centric space group Pbcn and the following unit cell parameters: a = 7.2887 (4), b = 9.1728 (6), c = 23.2169 (19) ?, Z = 4 and V = 1552.23 (18) ?3. The crystal structure has been solved and refined to R = 0.074 and R(w) = 0.173. The [H2PO4]- entities are associated by O---H...O strong hydrogen bonds to form layers. These latters are interconnected with the organic entities via (N)-H...O hydrogen bonds. In this atomic arrangement, H bonds between the different species play an important role in the three-dimensional network. This compound has also been characterized by infrared spectroscopy, solid state MAS-NMR and thermal analysis.

关键词： X-ray Diffraction NMR Spectroscopy IR Spectroscopy ATG

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Evaporation of a Thin Binary Liquid Film by Forced Convection into Air and Superheated Steam

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Journal of Thermal Science 2010年第4期19卷 346-356页

作者： Abdelaziz nasr Chokri Debbissi Sassi ben nasrallah LESTE cole Nationale d'Ingenieurs de MonastirUniversite de MonastirTunisie

This paper deals with a numerical analysis of the evaporation of a thin binary liquid film by forced convection inside a channel constituted by two *** first plate is externally insulated and wetted by a thin water ethylene glycol film while the second is dry and *** first part is concerned with the effects of inlet ambiance conditions and the liquid concentration of ethylene glycol on the distribution of the velocity,temperature,concentrations profiles and the axial variation of the evaporation *** second part is focused on the inversion temperature point of the evaporation of binary liquid *** show that the inversion temperature phenomenon for the evaporation of binary liquid mixture is observed for high liquid concentration of ethylene *** present results show that in the inlet temperature range considered here,the inversion temperature does not exit for the evaporation of pure ethylene glycol.

关键词： Binary liquid film evaporation inversion temperature forced convection combined heat and mass transfer

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On a Hybrid Preamble/Soft-Output Demapper Approach for Time Synchronization for IEEE 802.15.6 Narrowband WBAN

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China Communications 2015年第2期12卷 1-10页

作者： Imen nasr Leila Najjar Atallah Sofiane cherif YANG Jianxiao WANG Kunlun Unité d'Informatique et d'Ingènierie des Systemes(U2IS) Ecole Nationale Supérieure de Techniques Avancées(ENSTA Paris Tech) Communication Signal and Image(COSIM) LaboratoryHigher School of Communications of Tunis(Sup'Com) Network Coding and Transmission Laboratory Shanghai Jiao Tong University

In this paper,we present a maximum likelihood(ML) based time synchronization algorithm for Wireless Body Area Networks(WBAN).The proposed technique takes advantage of soft information retrieved from the soft demapper for the time delay *** algorithm has a low complexity and is adapted to the frame structure specified by the IEEE 802.15.6standard[1]for the narrowband *** results have shown good performance which approach the theoretical mean square error limit bound represented by the Cramer Rao Bound(CRB).

关键词： WBAN IEEE 802.15.6 time synchronization ML estimation soft demapping

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Interactions of zinc and cadmium toxicity in their effects on growth and in antioxidative systems in tomato plants (Solanum lycopersicum)

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Journal of Environmental Sciences 2011年第5期23卷 837-844页

作者： Jaouhra cherif Chamseddine Mediouni Wided ben Ammar Fatma Jemal Unit of Research "Nitrogenized Nutrition and Metabolism and Stress Proteins" UR 99/09-20 Department of BiologyFaculty of Science University of Tunis Tunis 2092 Tunisia Unit of Research "Nitrogenized Nutrition and Metabolism and Stress Proteins" UR 99/09-20 Department of BiologyFaculty of ScienceUniversity of Tunis Tunis 2092 Tunisia

The interaction between zinc and cadmium was investigated in tomato plants （Solanum lycopersicum）. Ten-day-old seedlings were treated with 10 μmol/L CdC12 associated to different concentrations of ZnC12 （10, 50, 100, and 150 μmol/L）. Zn supply clearly reduced Cd accumulation in leaves and simultaneously increased Zn concentration. Cd induced oxidative stress in leaves as indicated by an increase in thiobarbituric acid-reactive substances （TBARS） level and chlorophyll breakdown. Furthermore, compared with control, Cd- treated plants had significantly higher activities of superoxide dismutase （SOD, EC 1.***.1.1）, whereas, catalase （CAT, EC 1.***.1.6）, ascorbate peroxidase （APX, EC 1.***.1.11）, and glutathione reductase （GR, EC 1.***.4.2） activities were significantly suppressed by Cd addition. Zn supplementation, at low level, restored and enhanced the functional activity of these enzymes （SOD, CAT, APX and GR） as compared to Cd-alone-treated plants. The beneficial effect of adequate Zn level on Cd toxicity was confirmed by a significant decrease in TBARS level and restoration of chlorophyll content. However, when Zn was added at high level in combination with Cd there was an accumulation of oxidative stress, which was higher than that for Cd or excess Zn alone treatments. These results suggested that higher Zn concentrations and Cd are synergistic in their effect on plant growth parameters and oxidative stress.

关键词： Solanum lycopersicum cadmium zinc oxidative stress antagonism synergism.

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Isolation and characterization of facultative mixotrophic ammonia-oxidizing bacteria from constructed wetlands

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Journal of Environmental Sciences 2011年第10期23卷 1699-1708页

作者： Soulwène Kouki Neila Saidi Fadhel M'hiri Houda nasr Hanène cherif Hadda Ouzari Abdennaceur Hassen Laboratory of Treatment and Water Recycling Centre of Research and Water TechnologiesTechnopark of Borj-CedriaBP 2738020SolimanTunisia Unit of Transfer and Innovation Technologies Tunis International Centre for Environmental TechnologiesBoulevard of the Leader Yasser ArafatLa Charguia1080TunisTunisia Laboratory of Microbiology and Active Biomolecules Department of BiologyFaculty of Sciences of Tunis2092TunisTunisia

Autotrophic ammonia-oxidizing bacteria （AOB） have been widely studied in constructed wetlands systems, while mixotrophic AOB have been less thoroughly examined. Heterotrophic bacteria were isolated from wastewater and rhizospheres of macrophytes of constructed wetlands, and then cultivated in a mixotrophic medium containing ammonium and acetic acid. A molecular characterization was accomplished using ITS-PCR amplification, and phylogenetic analysis based on 16S rRNA gene Sequences. Results showed the presence of 35 bacteria, among 400 initially heterotrophic isolates, that were able to remove ammonia. These 35 isolates were classified into 10 genetically different groups based on ITS pattern. Then, a collection of 10 isolates were selected because of their relatively high ammonia removal efficiencies （ARE≥ 80%） and their phylogenetic diversity. In conditions of mixotrophy, these strains were shown to be able to grow （increase of optical density OD660 during incubation with assimilation of nitrogen into cellular biomass） and to oxidize ammonia （important ammonia oxidation efficiencies, AOE between 79% and 87%）. Among these facultative mixotrophic AOB, four isolates were genetically related to Firmicutes （Bacillus and Exiguobacterium）, three isolates were affiliated to Actinobacteria （Arthrobacter） and three other isolates were associated with Proteobacteria （Pseudomonas, Ochrobactrum and Bordetella）.

关键词： ammonia-oxidizing bacteria mixotroph constructed wetlands ammonia oxidation macrophytes' rhizosphere

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Crystal Structure of ZnCl<sub>3</sub>(Methyl-(2-Pyridin-2-yl-Ethyl)-Ammonium)

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American Journal of Analytical Chemistry 2015年第3期6卷 189-195页

作者： Mahjouba ben nasr Erwann Jeanneau Chérif ben nasr Université de Carthage Laboratoire de Chimie des Matériaux Faculté des Sciences de Bizerte Zarzouna Tunisie Centre Diffractométrie Henri Longchambon Université Claude Bernard Lyon 1 Villeurbanne France

A new Zn(II) complex with the monodentate ligand methyl-(2-pyridin-2-yl-ethyl)-ammonium, ZnCl3C8H13N2, has been prepared and characterized by single crystal X-ray diffraction. The Zn(II) ion is tetracoordinated by one nitrogen atom of organic ligand and three chlorine ligands. In the atomic arrangement, the ZnNCl3 tetrahedra form corrugated chains extending along the b-axis. The organic entities are located between these chains through N-H···Cl, C-H···Cl and C-H···N hydrogen bonds to form layers parallel to (b, c) plan. Among these hydrogen bonds two are bifurcated.

关键词： X-Ray Diffraction Coordination Compound Zinc Complex

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Synthesis, Crystal Structure and Infrared Characterization of Bis(4-dimethylamino-pyridinium) Tetrachlorocuprate

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American Journal of Analytical Chemistry 2015年第5期6卷 446-456页

作者： Mahjouba ben nasr Frédéric Lefebvre Chérif ben nasr Laboratoire de Chimie des Matériaux Faculté des Sciences de Bizerte Université de Carthage Zarzouna Tunisie Laboratoire de Chimie Organométallique de Surface (LCOMS) Ecole Supérieure de Chimie Physique Electronique Villeurbanne France

The chemical preparation, crystal structure and spectroscopic characterization of a novel organic-inorganic hybrid material, bis(4-dimethylaminopyridinium) tetrachlorocuprate, have been reported. This compound crystallizes in the monoclinic system in space group C2/c and cell parameters a = 12.4356 (18), b = 12.0901 (17), c = 14.094 (2) Å, β = 115.303 (2)°, Z = 4 and V = 1915.8 (5) Å3. In the title salt, (C7H11N2)2CuCl4, both 4-dimethylaminopyridinium cations are protonated at their pyridine N atoms. The geometry of the CuCl2-4 ions is intermediate between tetrahedral and square planar. The atomic arrangement can be described by an alternation of inorganic layers built up by tetrachlorocuprate anions and organic layers formed by 4-dimethylaminopyridinium cations. The organic layers are located in sandwich between the inorganic layers. The anionic and cationic layers are held together by N-H···Cl and C-H···Cl hydrogen bonds into a three-dimensional network. The individual cations are π-π stacked with their neighbors at a distance of 3.7622 (5) Å. The vibrational absorption bands were identified by infrared spectroscopy and DFT calculations allowed their attribution.

关键词： Crystal Structure 4-Dimethylaminopyridine Hydrogen Bonds π-π Interactions DFT Calculations

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Harmonic Distortion Rate Analysis of H-Bridges Multilevel Inverter

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材料科学与工程（中英文B版） 2011年第3期1卷 308-315页

作者： Mohamed Nejib ben nasr Khammassi Anis Kebir Faouzi ben Ammar Unite de recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-1008 Universite de Tunis Tunisia Unite de recherche. LSE INSAT Centre Urbain Nord BP 676 1080 Tunisia

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Cascaded H-Bridges Asymmetrical 11-Levels Optimization

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材料科学与工程（中英文B版） 2011年第4期1卷 496-503页

作者： Mohamed Nejib ben nasr Khammassi Anis Kebir Faouzi ben Ammar Unite de Recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-lO08 Universite de Tunis Tunisia Unitd de Recherche.＂ LSE INSA T Centre Urbain Nord BP 676 1080 Tunis

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