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Effect of temperature and pH value on cation exchange performance of a natural clay for selective(Cu2+,Co2+) removal:Equilibrium,sorption and kinetics

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Progress in Natural Science:Materials International 2013年第1期23卷 23-35页

作者： Ramzi Chalghaf Walid Oueslati Marwa Ammar hafsia ben Rhaiem Abdesslem ben Haj Amara UR05/13-01:Physique des Matériaux Lamellaires et Nanomatériaux Hybrides(PMLNMH) Facultédes Sciences de BizerteZarzouna 7021Tunisia

This work aims at investigating the strain effect,created by varying pH solution and continuous heating cycle,on the cation exchange process in the case of Na-rich montmorillonite sample in contact with bi-ionic solution with variable concentration,saturated respectively by Co2+ and Cu2+ *** ionic exchange process is characterized using XRD analysis obtained through the comparison of experimental XRD patterns with calculated ones,which allowed us to determine several structural parameters related to the nature,abundance,size,position and organization of exchangeable cation and water molecule in the interlamellar space along the ***,the proposed theoretical models,for the stressed samples,show that the structure presents an interstratified hydration character and proves the coexistence of more than two ''crystallite'' specie in the *** perturbation types have an obvious effect on the selective exchange process for all stressed samples,where the interlayer space is characterized by the coexistence of more one exchangeable cation.

关键词： Geological membrane Soil decontamination Alkaline strain Thermal stress Quantitative XRD analysis Ionic exchange process

Functionalization and Structural Characterization of a Novel Nacrite-LiCl Nanohybrid Material

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American Journal of Analytical Chemistry 2015年第3期6卷 202-215页

作者： Nouha Jaafar Sonia Naamen hafsia ben Rhaiem Abdesslem ben Haj Amara Laboratory of Physics of Lamellar Hybrid Materials and Nanomaterials Department of Physics Faculty of Science of Bizerte Zarzouna Tunisia

The nacrite-LiCl hybrid composite material was prepared at room temperature by indirect inter-calation of lithium chloride between the planar layers of nacrite, a clay mineral, using acetone as a solvent. The structural identification of the hybrid clay material was determined by means of X-ray diffraction (XRD), thermogravimetric analysis (TGA) and infrared spectroscopy (IR). The qualitative XRD analysis showed that the basal spacing value increased from 0.72 nm to 1.14 nm and revealed that the alkali halide intercalated successfully in the interlayer space of the nacrite framework. The quantitative XRD analysis allowed us to determine the optimum structural parameters related to the position and number of keyed ions and water molecules per half unit cell calculated along the c* axis and the goodness of fit parameter (Rp). The thermal properties of the elaborated hybrid were in great accordance with the XRD study and confirm the intercalation of the hydrated salt in the interlamellar space of nacrite. Moreover, IR spectroscopy enabled the study of the interactions between the silicate ‘‘networks’’ and the alkali halide.

关键词： Nacrite Composite Material X-Ray Diffraction TG Analysis Infrared Spectroscopy

Elaboration of Amorphous-Clay Hybrid: (Al2Si2O7·1/2Li2O) Designed as a Single Ion Conducting Solid Electrolyte for Li-Ion Batteries

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American Journal of Analytical Chemistry 2014年第17期5卷 1261-1272页

Keying of lithium chloride alkali halide salt into the interlamellar space of nacrite clay mineral leads to a stable hybrid material that after calcination under inert atmosphere at 723 - 873 K induces an amorphous metahybrid. The electrochemical impedance spectroscopy (EIS) was performed to investigate the electric/dielectric properties of the hybrid with various parameters: frequency and temperature. Equivalent circuit was proposed to fit the EIS data. The experiment results show that the ionic conduction mechanism is related to the motion of Li+ cations which are thermally activated, named the hopping model. Furthermore, the resulting metahybrid obtained from dehydroxylation of the formal hybrid shows a superionic behavior with high ionic conductivity up to 10﹣2 S·m﹣1, good electrochemical stability and can be used as a solid electrolyte material for Li-ion batteries.

关键词： Nacrite Clay Hybrid Amorphous Solid Electrolyte Lithium-Ion Battery

Performance Improving of a Concentrating Photovoltaic System by Using a New Optical Adhesive

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Journal of Modern Physics 2021年第12期12卷 1607-1617页

作者： Intissar benrhouma Nabil ben hafsia Bechir Chaouachi Marta Victoria Ignacio Anton Energy Water Environment and Process Analysis Laboratory National Engineering School of Gabes University of Gabes Gabes Tunisia Instituto de Energía Solar Universidad Politécnica de Madrid Ciudad Universitaría Madrid Spain

The objective of this present study is to manufacture a new silicone-based adhesive which is used for gluing and bonding the second optical elements (SOE) with Concentrating Photovoltaic solar cell (CPV) in order to guarantee a thickness that can provide a good silicone adherence to obtain long term stability and keeping a good solar transmittance performance, too. This new adhesive is made up of a mixture of silicone and transparent glass balls. The experimental part consists of the choice of the best size of glass balls with the suitable proportion of the glass balls weight in the mixture. For this purpose, ten samples were manufactured for every category of glass balls and weight ratio. Glass ball sizes between 100 and 1100 μm, and weight ratios between 1 and 10% were analyzed. For each category of glass balls, four proportions were mixed with the silicone. The thicknesses and transmittance of every sample were measured with appropriate instruments. The experimental results illustrate that the mixture containing balls with sizes inferior to 106 μm, is the best mixture which assures adhesive minimum thickness value necessary for an efficient mechanical bond and preserves also a good transmittance of solar irradiance.

关键词： Secondary Optical Elements (SOE) Concentrating Photovoltaic Solar Cell (CPV) New Adhesive Thickness Transmittance

Relation Between Mechanical Constraints and The Hydration Behaviour in the Case of Na-Montmorillonite:Structural Analysis and Elastics Properties

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矿物学报 2013年第S1期33卷 95-95页

作者： Walid Oueslati hafsia ben Rhaiem Abdesslem ben Haj Amara SUR05/13-01 Physique des Matériaux Lamellaires et Nanomatériaux Hybrides (PMLNMH) Faculté des Sciences de BizerteZarzouna 7021Tunisia

The experimental prediction of the mechanical properties of minerals remains difficult because of their small particle size (typically < 2 micrometers). This work aims at examining, the effect of an applied mechanical constraint on the hydration behaviour in the case of Na rich-montmorillonite and its relation with the elastic properties. The mechanical constraint is created, at the laboratory scale, by applying a monoaxial pressure for unstressed host material (i.e. Na rich montmorillonite). The structural analysis before and after stress is achieved using an XRD profile modeling approach. This investigation allowed us to determine several structural parameters related to the nature, abundance, size, position and organization of exchangeable cation and water molecule in the interlamellar space along the c* axis. In order to evaluate the affected elastic properties, the GULP code have been used to study the structure and the interlamellar organization. Indeed, the bulk modulus and elastic constants of montmorilonite have been calculated from first principles within density functional theory (DFT). The obtained Young’s modulus for Na-montmorillonite interlayer varies from 5 GPa to 16 GPa. According to the interlamellar space configuration the calculated elastic constant tensors indicate that the a direction is slightly more flexible than the b direction. The calculated elastic constant tensor along c is much lower than the constants calculated along a and b.

关键词： Na rich-montmorillonite hydration behavior GULP code elastic properies

Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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Nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin Jiang Hui-Na Liu Yu-Fan Yang Zhi-Cheng Zhang Qi Dai Xiao-Yan Bao Lin-Jie Wu Ya-Xin Qin Xin Tan Xiao-Yan Sun Xu-Fang Ying Zhi-Qing ben Min Han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China Hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering RNA(siRNA)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRNA to overcome the problem of siRNA release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRNA,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering RNA(siRNA) doxorubicin

Five Years Beyond Sendai——Can We Get Beyond Frameworks?

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International Journal of Disaster Risk Science 2020年第2期11卷 239-249页

作者： ben Wisner Institute for Risk and Disaster Reduction University College LondonLondon WCIE 6BTUK

The Sendai Framework for Disaster Risk Reduction 2015–2030(SFDRR) and its implementation is evaluated after its first five years. A dozen questions that the author and a colleague used in their evaluation of the Hyogo Framework for Action 2005–2015(HFA) are repeated. Improvements are noted in relation to possible coherence and alignment with other components of the Post-2015 Agenda, especially as regards climate change and urban disasters as well as the higher visibility of civil society and women, and also regarding the specificity of targets and monitoring of governments’ successes. Nevertheless, the overall conclusion is that both the HFA and the SFDRR fail to deal with root causes of disaster. A new,radically proactive leadership role is suggested for the United Nations Office for Disaster Risk Reduction in partnership with civil society in identifying and warning all engaged in Post-2015 Agenda activities of possible creation of new risk by agenda implementation activities,especially for the poor and already-marginalized.

关键词： Civil society Climate change Disaster risk reduction Hyogo framework Sendai framework

Taxonomy of the lesser jerboa Jaculus jaculus (Dipodidae,Rodentia) based on allozymic and morphological variation

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Current Zoology 2010年第4期56卷 421-431页

作者： Abderraouf ben FALEH Abdelwaheb ben OTHMEN Khaled SAID Génétique Biodiversité et Valorisation des Bio-ressources (UR03ES09) Institut Supérieur de Biotechnologie de Monastir 5000 Génétique Biodiversité Valorisation des Bio-ressources (UR03ES09) Institut Supérieur de Biotechnologie de Monastir 5000

The lesser Egyptian jerboa Jaculus jaculus, is a member of the subfamily Dipodinae, known to have a number of subspecies. Previous studies of J. jaculus from North Africa found various morphological forms of unknown taxonomic status, which are frequently grouped into two taxa： J. jaculus and J. deserti. We assessed the taxonomic status of this taxon in Tunisia using allozymic （phylogenetic analysis of 23 genetic loci encoding 16 enzymatic proteins） and morphological （multivariate analysis of 13 craniodental characters） analyses of 136 J. jaculus specimens collected from seven localities within its distribution range. Allozymic analysis clearly indicated the existence of two distinct groups of J. jaculus, with a mean genetic distance （D） value of 0.99 and FΩ=0.52. Individuals within the two groups did not show any obvious geographical structuration, even within the Matmata locality which represents the meeting point for the two groups where they were found in sympatry. Additionally, morphometric analysis of 13 craniodental characters was clearly separated the two groups. These results were obtained over a very restricted area of the total distribution of J. jaculus and strongly suggest the occurrence of two separate and often sympatric species within the currently accepted *** in Tunisia： *** and J. deserti

关键词： Dipodidae Jaculus jaculus Taxonomy Allozyme Morphomotric analysis Tunisia

Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)

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Acta Geochimica 2024年第2期43卷 366-384页

作者： Rania ben Aissa Wiem ben Aissa Said Tlig Lassaad ben Aissa Abdessalem ben Haj Amara Faculty of Science of Bizerte University of Carthage7021 ZarzounaBizerteTunisia Laboratoire de Recherche Ressources Materiaux et EcosystemesUniversity of Carthage7021 ZarzounaBizerteTunisia Department of Geology University Claude Bernard Lyon 169622 VilleurbanneFrance Faculty of Science of Tunis University of Tunis-El ManarRommana1068 TunisTunisia

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

关键词： Ore-formingﬂuids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia