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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEM Hajer KTARI Lilia GARCIA-GRANDA Santiago DAMMAK Mohamed laboratoire de Chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia laboratoire de Chimie Physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry

Biological treatment of fish processing wastewater:A case study from Sfax City(Southeastern Tunisia)

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Journal of Environmental Sciences 2015年第4期27卷 102-112页

作者： Meryem Jemli Fatma Karray Firas Feki Slim Loukil Najla Mhiri Fathi Aloui Sami Sayadi laboratoire des Bioprocedes Environnementaux Pole d'Excellence Régional(PERAUF)Centre de Biotechnologie de SfaxUniversite de Sfax

The present work presents a study of the biological treatment of fish processing wastewa at salt concentration of 55 g/L. Wastewater was treated by both continuous stirred-ta reactor（CSTR） and membrane bioreactor（MBR） during 50 and 100 days, respectively. Th biological processes involved salt-tolerant bacteria from natural hypersaline environme at different organic loading rates（OLRs）. The phylogenetic analysis of the correspond excised DGGE bands has demonstrated that the taxonomic affiliation of the most domin species includes Halomonadaceae and Flavobacteriaceae families of the Proteobacteria（Gamm proteobacteria class） and the Bacteroidetes phyla, respectively. The results of MBR w better than those of CSTR in the removal of total organic carbon with efficiencies from 97 to 98.6%. Nevertheless, salinity with increasing OLR aggravates fouling that requires m cleaning for a membrane in MBR while leads to deterioration of sludge settleability a effluent quality in CSTR.

关键词： Membrane bioreactor Saline effluents Organic removal PCR-DGGE

Prediction model for the diffusion length in silicon-based solar cells

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Journal of Semiconductors 2009年第7期30卷 3-6页

作者： Cheknane A Benouaz T laboratoire d'Etude et Dveloppement des Matriaux Semiconducteurs et Dilectrques Universit Amar Telidji de Laghouat laboratoire de Modlisation UniversitAbou BakarBelkaid de Tlemcen Algrie

A novel approach to compute diffusion lengths in solar cells is presented. Thus, a simulation is done; it aims to give computational support to the general development of a neural networks （NNs）, which is a very powerful predictive modelling technique used to predict the diffusion length in mono-crystalline silicon solar cells. Furthermore, the computation of the diffusion length and the comparison with measurement data, using the infrared injection method, are presented and discussed.

关键词： diffusion length minority-cartier lifetime infrared injection solar cell prediction modelling

detailed Analysis of the Flow in the Inducer of a Transonic Centrifugal Compressor

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Journal of Thermal Science 2012年第1期21卷 1-12页

作者： Nicolas Buffaz Isabelle Trébinjac laboratoire de Mécanique des Fluides et d'Acoustique Ecole Centrale de Lyon 36 av. Guy de Collongue

Numerical and experimental investigations were conducted in a transonic centrifugal compressor stage composed of a backswept splittered unshrouded impeller and a vaned diffuser. A detailed analysis of the flow in the inducer (i.e. the entry zone of the impeller between the main blade leading edge and the splitter blade leading edge) is proposed from choke to surge. Steady and unsteady simulations were performed using the code elsA, which uses a multi-domain approach on structured meshes and solves the compressible RANS equations, associated with a two-equation turbulence model k-l in the rotating frame of reference. The 1MW LMFA-ECL test rig was used for carrying out the tests in the compressor stage. Unsteady pressure measurements up to 150 kHz and Laser Doppler Anemometry measurements were performed in the inducer. A good agreement is obtained between the experimental and numerical data even if an over dissipation is noticed in the numerical results. The change in flow pattern from choke to surge is mainly due to a change in the tip leakage flow trajectory which straightens, leading to a flow blockage of an individual passage near shroud. A spectral analysis shows that only the blade passing frequency and its harmonics compose the various spectra obtained from choke to surge.

关键词： transonic centrifugal compressor inducer unsteady pressure measurements

ESSENTIAL APPROXIMATE POINT SPECTRA FOR UPPER TRIANGULAR MATRIX OF LINEAR RELATIONS

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Acta Mathematica Scientia 2013年第4期33卷 1187-1201页

作者： Souhir ELLEUCH Maher MNIF Département de Mathématiques Université de Sfax Faculté des Sciences de SfaxLaboratoire de Physiques Mathématiques

When A E ∈LR（H） and B E ∈LR（K） are given, for C E∈LR（K, H） we denoteby Mc the linear relation acting on the infinite dimensional separable Hilbert space H Kof the formIn this paper, we give the necessary and sufficient conditionson A and B for wh{ch Mc is upper semi-Fredholm with negative index or Weyl for some C C ∈LR（K, H）.

关键词： linear relation Fredholm and semi-Fredholm relation essential approximatepoint spectra for linear relation

Modal decomposition for the Analysis of the Rotor-stator Interactions in Multi-stage Compressors

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Journal of Thermal Science 2012年第3期21卷 276-285页

作者： N.Courtiade X.Ottavy N.Gourdain laboratoire de Mécanique des Fluides et d'Acoustique Ecole Centrale de Lyon CERFACS CFD Team

A modal analysis method of the rotor-stator interactions in multistage compressors has been developed by LMFA. This method, based on a double modal decomposition of the flow over space and time, has been applied to nu- merical and experimental results of the high-speed 3Y2-stage compressor CREATE based at LMFA, Lyon-France. It reveals the presence of a very strong rotor-stator interaction which completely drives the flow at casing behind all the rotors. This modal analysis method applied to an unsteady RANS simulation permits to calculate the en- ergy of the rotor-stator interactions and to plot energetic meridian maps to explain experimental results and to analyze the interaction in the whole machine.

关键词： rotor-stator interactions modal analysis multistage compressors numerical and experimental results

Phenological stage effect on phenolic composition and repellent potential of Mentha pulegium against Tribolium castaneum and Lasioderma serricorne

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Asian Pacific Journal of Tropical Biomedicine 2018年第4期8卷 207-216页

作者： Nidhal Salem Jazia Sriti Olfa Bachrouch Kamel Msaada Saber Khammassi Majdi Hammami Saoussen Selmi Emna Boushih Marwa Ouertani Nesrine Hachani Manef Abderraba Brahim Marzouk Ferid Limam Jouda Mediouni Ben Jemaa laboratoire des Substances Bioactives Centre de Biotechnologie a la Technopole de Borj Cedria laboratoire de Protection des Vegetaux Institut National de la Recherche Agronomique de Tunisie (INRAT) Institut Superieur des Sciences Biologiques Appliquees de Tunisia laboratoire de Biotechnologie Appliquee a l'Agriculture Institut National de la Recherche Agronomique de Tunisie (INRAT)

Objective:To elucidate for the first time the phenological stage effect on polyphenol,flavonoid and proanthocyanidin contents of pennyroyal(Mentha pulegium)as well as their antioxidant capacities and insecticidal potentials against Tribolium castaneum and Lasioderma ***:Crude methanol extracts from pennyroyal(Mentha pulegium)aerial parts were evaluated for their anti radical,reducing power activities and repellent potentials against selected coleopteran insects during different phenological ***:Phenolic contents of pennyroyal aerial parts and their antioxidant effects were significantly dependent on maturity stage of the *** maximum of phenol production was reached during the full flowering *** was the major phenol in Mentha pulegium with an amount of6.01 mg/g of dry vegetable matter during this ***,at fructification stage,the highest antioxidant activity was not related to high phenolic *** repulsive effect of pennyroyal extract showed that Lasioderma serricorne was more susceptible to pennyroyal extract than Tribolium castarneum with corresponding median repellent dose values of 0.124and 0.006 mg/mL ***,great differences in insect repulsion depending on extract concentrations,exposure time and developmental stage was *** the lowest concentration(0.125 mg/mL),the repellent effect against Tribolium reached its maximum(90%)during the fructification stage(after 24 h of exposure)while this repellent effect was 80%during the vegetative ***:Due to the strong insecticidal potential of pennyroyal extracts,this study highlights the therapeutic properties of this plant and encourages its use as a safer,environmental-friendly and efficient insecticide in food industry.

关键词： Apigenin Lasioderma Repellent activity Full flowering stage

Electron Backscattered Diffraction of Transgranular Crack Propagation in Soft Steel

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Chinese Physics Letters 2007年第6期24卷 1759-1762页

作者： A. Boumaiza T. Baudin N. Rouag R. Penelle laboratoire Microstructures et defauts Universit6 Mentouri Constantine Algdrie laboratoire de Physico-Chimie de l'Etat Solide UMR CNRS 8648 Paris-Sud Orsay France

We consider the crack propagation in a soft steel sheet during the formation. The drawability is considered in relation with the structural anisotropy, the mechanical behaviour is related to both the grain morphology and the texture. The structure heterogeneity could lead to the apparition of micro-cracks. The results show the texture effect on the crack propagation and on the crack arrest in soft steel during the formation. The EBSD technique allows to show that the adjustment of the grain orientation from the initial main component {111}（112） towards the deformation orientation {111}（110） incites a trans-granular crack through a grain with initial {111}（112） orientation in a globally ductile material. It is the presence of grains with {111}（110） orientation which permits the closing of micro-cracks.

关键词： INITIATION GROWTH

Inf-convolution of G-expectations

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Science China Mathematics 2010年第8期53卷 1957-1970页

作者： BUCKDAHN Rainer laboratoire de Math'ematiques CNRS-UMR 6205Universite' de Bretagne Occidentale

In this paper we will discuss the optimal risk transfer problems when risk measures are generated by G-expectations,and we present the relationship between inf-convolution of G-expectations and the infconvolution of d... 详细信息

关键词： inf-convolution G-expectation G-normal distribution G-Brownian motion

Electronic Absorption Spectroscopy of H2X （X=O, Te, Po）： Theoretical Treatment of Spin-Orbit Effects

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Chinese Journal of Chemical Physics 2009年第2期22卷 171-177页

作者： Chérif A. A. Ndoye Chantal Daniel laboratoire de Chimie Quantique Institut de Chimie UMR 7177 CNRS-Université de Strasbourg 4 Rue Blaise Pascal 67000 Strasbourg France

The electronic spectroscopy of H2X （X=O, Te, Po） was investigated by means of spinorbit configuration interaction （EPCISO） and restricted active space state interaction （SORASSI）. The transition energies to the low-lying singlet and triplet states of H2O, in which the SO interaction is zero, compare rather well with the experimental data as well as to other theoretical values. The theoretical electronic absorption spectrum is characterized by three allowed transitions A^1B1 （2px（O）→σ^＊g/3s（O））, B^1A1（σg→σ^＊g/3s（O）） and A^1S2（σg→σ^＊u） calculated at 7.68, 9.94, and 11.72 eV, respectively. The theoretical absorption spectra of H2X （X=Te, Po） are shifted to the red with the A^1B1 （npx（X）→σ^＊g） states calculated at 5.06 eV （H2Te） and 4.40 eV （H2Po） and the A^1B2 （σg→σ^＊u） states calculated at 7.89 eV （H2Te） and 7.77 eV （H2Po）. The largest SO splitting amounts to 0.34 eV and is found for the lowest a^3A1 of H2Po. In H2Te the SO effects are still negligible with a maximum splitting of 0.04 eV for the lowest a^3B2. The two methods lead to comparable results but the EPCISO approach depends strongly on the reference wavefunction.

关键词： Spin-orbit Excited state Group Ⅵ dihydride