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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

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

Experimental design of paraffin/methylated melamine-formaldehyde microencapsulated composite phase change material and the application in battery thermal management system

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Journal of Materials Science & Technology 2024年第2期169卷 124-136页

作者： Que Huang Silong Wang Jichun He Dengji Xu Safaa NAbdou Mohamed MIbrahim Shiqi Sun Yanjun chen Handong Li ben Bin Xu changcheng Liu Zeinhom M.El-Bahy Zhanhu Guo School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Institute of Advanced Energy Materials and Systems North University of ChinaTaiyuan 030051China School of Resources and Safety Engineering Central South UniversityChangsha 410010China School of Medical and BioInformation Engineering Northeastern UniversityShenyang 110819China Department of chemistry Khurmah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

In order to maintain the optimal operating temperature of the battery surface and meet the demand for thermal storage technology,battery thermal management system based on phase change materials has attracted increasing *** this work,a kind of core-shell structured microcapsule was synthesized by an in-situ polymerization,where paraffin was used as the core,while methanol was applied to mod-ify the melamine-formaldehyde shell to reduce toxicity and improve thermal ***,three different types of heat conductive fillers with the same content of 10 wt.%,i.e.,nano-Al_(2)O_(3),nano-ZnO and carbon nanotubes were added,generating *** microcapsules were uniform,and were not affected by the thermal fillers,which were evenly dispersed *** composite sample with carbon nanotubes(10 wt.%)showed the highest thermal conductivity of 0.50 W/(m K)and latent heat of 139.64 J/***,according to the leakage testing and battery charge/discharge experiments,compared with Al_(2)O_(3)and ZnO,the addition of carbon nanotubes remarkably enhances the heat storage ability as latent heat from 126.98 J/g for the prepared sample with Al_(2)O_(3)and 125.86 J/g for the one with ZnO,then to 139.64 J/g,as well as dissipation performance as a cooling effect by decreasing the sur-face temperature of battery from 2%to 12%of microcapsule,composite sample with carbon nanotubes presents a broad application prospect in battery thermal management system and energy storage field.

关键词： Microcapsule Phase change material Battery Carbon nanotube Safety

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

MXene@c-MWCNT Adhesive Silica Nanofiber Membranes Enhancing Electromagnetic Interference Shielding and Thermal Insulation Performance in Extreme Environments

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Nano-Micro Letters 2024年第10期16卷 82-98页

作者： Ziyuan Han Yutao Niu Xuetao Shi Duo Pan Hu Liu Hua Qiu Weihua chen ben Bin Xu Zeinhom MEl-Bahy Hua Hou Eman Ramadan Elsharkawy Mohammed AAmin chuntai Liu Zhanhu Guo Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002People's Republic of China School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026People's Republic of China Key Laboratory of Multifunctional Nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123People's Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'an 710072People's Republic of China College of chemistry&Green Catalysis Center Zhengzhou UniversityZhengzhou 450001People's Republic of China Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon Tyne NE18UK Department of chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt Department of chemistry Faculty of ScienceNorthern Border UniversityArarSaudi Arabia Department of chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia

A lightweight flexible thermally stable composite is fabricated by com-bining silica nanofiber membranes(SNM)with MXene@c-MWCNT hybrid *** flexible SNM with outstanding thermal insulation are prepared from tetraethyl orthosilicate hydrolysis and condensation by electrospinning and high-temperature calcination;the MXene@c-MWCNT_(x:y)films are prepared by vacuum filtration *** particular,the SNM and MXene@c-MWCNT_(6:4)as one unit layer(SMC_(1))are bonded together with 5 wt%polyvinyl alcohol(PVA)solution,which exhibits low thermal conductivity(0.066 W m^(-1)K^(-1))and good electromagnetic interference(EMI)shielding performance(average EMI SE_(T),37.8 dB).With the increase in func-tional unit layer,the overall thermal insulation performance of the whole composite film(SMC_(x))remains stable,and EMI shielding performance is greatly improved,especially for SMC_(3)with three unit layers,the average EMI SET is as high as 55.4 *** addition,the organic combination of rigid SNM and tough MXene@c-MWCNT_(6:4)makes SMC_(x)exhibit good mechanical tensile ***,SMC_(x)exhibit stable EMI shielding and excellent thermal insulation even in extreme heat and cold ***,this work provides a novel design idea and important reference value for EMI shielding and thermal insulation components used in extreme environmental protection equipment in the future.

关键词： SiO_(2)nanofiber membranes MXene@c-MWCNT Composite film Thermal insulation Electromagnetic interference shielding

Regulating microstructure and composition by carbonizing in-situ grown metal-organic frameworks on cotton fabrics for boosting electromagnetic wave absorption

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Nano Research 2024年第8期17卷 7290-7300页

作者： Jie Jin Hongsen Long Hu Liu Yan Guo Tiantian Bai ben Bin Xu Mohammed A.Amin Hua Qiu Mohamed H.Helal chuntai Liu changyu Shen Zeinhom M.El-Bahy Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China china State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410000China School of Electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Complex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Composites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK Department of chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of chemistry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia Department of chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-temperature carbonized metal-organic frameworks(MOFs)derivatives have demonstrated their superiority for promising electromagnetic wave(EMW)absorbers,but they still suffer from limited EMW absorption capacity and narrow *** the advantage of microstructure and chemical composition regulation for the design of EMW absorber,hierarchical heterostructured MoS_(2)/CoS_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(MCC@CCF)is prepared by growing ZIF-67 MOFs onto CF surface,chemical etching,and *** from the dual loss mechanism of magnetic-dielectric multicomponent carbonized MOFs,chemical etching and carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching and stronger absorption capacity via internal reflection,doped heteroatoms(Mo,N,S)to supply additional dipolar polarization loss,and numerous heterointerfaces among MoS_(2),CoS_(2),Co_(3)O_(4),and CCF that produce promoted conduction loss and interfacial polarization ***,a minimal reflection loss of−52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sample thickness and filler loading,showing excellent EMW absorption *** research is of great value for guiding the research on MOFs derivatives based EMW absorbing materials.

关键词： metal-organic frameworks hierarchical structure chemical etching sulfurization electromagnetic wave absorption

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

This paper represents comparative study on two control techniques applied to H-bridges multilevel inverter. The considered techniques are standard PWM and harmonic elimination control. Their performances are compared in terms of THD and commutation’s losses so that the choice of power switches is optimized. Simulation results indicated that the harmonic elimination technique exhibits better results than the standard PWM technique, which is sustained by the reduce of the commutation losses, and a power rise for the switches ensuring the use of GTOs, IGCTs.

关键词：多电平逆变器 H桥失真率 PWM技术谐波技术标准电源开关控制技术

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

The following dissertation aims at investigating the multilevel topology basis through the analyses of the harmonic elimination control modeling methodology of the asymmetrical inverter. Thus the contribution of this paper can be summarized mainly by the fact that the pre-calculated PWM control used to control the symmetrical structure, as applied to the asymmetrical structure with a reduced number of cells, provides the same performance level resolution and signal strength to the load terminals, which guarantees a constant voltage frequency report. This observation is similar for the three cells, which allows the use of different drivers such as MOSFET, IGBT and GTO. These results have a good performance from the intrinsic proprieties of each semiconductor for each cell.

关键词：水平分辨率不对称非对称结构优化 H桥级联 MOSFET 消谐控制

Adsorption of rare earth elements onto diatomite M45:Experimental investigations and modeling with statistical physics theory

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Journal of Rare Earths 2023年第11期41卷 1805-1811,I0006页

作者： Fatma Dhaouadi Guilherme L.Dotto Julien Vieillard Diana Pinto Luis F.O.Silva Éder C.Lima Mu Naushad Fatma Aouaini Samia nasr Adrián Bonilla-Petriciolet Abdelmottaleb ben Lamine Laboratory of Quantum and Statistical Physics LR18ES18Faculty of Sciences of MonastirMonastir UniversityMonastirTunisia Research Group on Adsorptive and Catalytic Process Engineering(ENGEPAC) Federal University of Santa MariaAv.Roraima1000-797105–900Santa MariaRSBrazil NormandieUniversité UNIROUENINSA RouenCNRSCOBRA(UMR 6014)27000EvreuxFrance Universidad De La Costa Calle 58#55-66080002BarranquillaAtlánticoColombia Advanced Materials Research chair Department of ChemistryCollege of ScienceKing Saud UniversityRiyadh11451Saudi Arabia Department of chemistry College of ScienceBuilding#5King Saud UniversityRiyadhSaudi Arabia Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbha61413P.O.Box 9004Saudi Arabia chemistry Department Faculty of ScienceKing Khalid UniversityP.O.Box 9004Abha61413Saudi Arabia Instituto Tecnológico de Aguascalientes 20256AguascalientesMexico

The separation of rare earth elements using diatomite M45 from aqueous solutions was *** experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were quantified under strongly acidic conditions(pH 2)at 298-328 *** adsorption equilibria of these earth elements were analyzed using two statistical physics models(homogeneous and heterogeneous monolayer models).The results show that the adsorption of these ions implies a multiionic mechanism,which is ***-containing functional groups are responsible for the adsorption of these rare-earth elements on the diatomite surface.A heterogeneous statistical physics model confirms that two Si-based functional groups participate in the separation of these *** calculated adsorption capacities at saturation follow the order:neodymium>cerium>*** interaction energies range from 28600 to 40100 J/mol,indicating physical adsorption on diatomite *** study demonstrates that diatomite M45 is a promising separation medium that can be used for the recovery of REEs dissolved in aqueous solutions via adsorption.

关键词： Lanthanum Cerium Neodymium Adsorption Diatomite M45 Statistical physics model