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Structural and Relaxor Behavior of Pb0.95 （La1-xBix）0.05 [（Zr0.6Ti0.4）0.95（M n1/3S b2/3）0.05]O3 Ceramics

材料科学与工程（中英文A版） 2013年第9期3卷 615-620页

作者： hayet menasra Zelikha Necira Ahmed Boutarfaia Applied Chemistry Laboratory Exact and Natural and Life Sciences Faculty Materials Science Department Mohamed KheiderUniversity of Biskra BP I 45 7000 Algeria Exact and Natural and Life Sciences Faculty Materials Science Department University of Ouargla Ouargla 35000 Algeria

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Microstructure and Dielectric Properties of Bi Substituted PLZMST Ceramics

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Materials Sciences and Applications 2013年第5期4卷 293-298页

作者： hayet menasra Zelikha Necira Karima Bouneb Abdelhak Maklid Ahmed Boutarfaia Applied Chemistry Laboratory Exact and Natural and Life Sciences Faculty Materials Science Department Mohamed Kheider University of Biskra Biskra Algeria

Bismuth (Bi) and lanthanum (La) doped lead manganese antimoine zirconate titanate (PZMST) ceramic powders have been synthesized by high temperature solid-state reaction method. Preliminary X-ray structural analysis of the compounds shows the formation of tetragonal structure. Scanning electron micrographs (SEM) shows a uniform grain distribution and grain size of the order of ~2.28 μm. Detailed dielectric studies of the Pb0.95(La1-z Biz)0.05[(Zr0.6Ti0.4)0.95(Mn1/3Sb2/3)0.05]O3 samples as a function of the temperature (from 25°C to 450°C) at frequency 1 kHz suggest that the compounds undergo a diffuse phase transition. The transition temperature shifts increase with increasing the Bi ratio. Diffusivity (γ) study of phase transition of these compounds provided its value from 1.59 to 1.78 indicating the degree of the disordering in the system.

关键词： PLZT Ceramics Grain Size Dielectric Properties Diffusivity (γ)

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Synthesis and Dielectric Properties of (0.80 - x)Pb(Cr1/5,Ni1/5,Sb3/5)O3-xPbTiO3-0.20PbZrO3Ferroelectric Ceramics

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Materials Sciences and Applications 2013年第11期4卷 746-750页

作者： Abdelhek Meklid Ahmed Boutarfaia Zelikha Necira hayet menasra Malika Abba Laboratory of Applied Chemistry Materials Science Department Mohamed Kheider University of Biskra Biskra Algeria Laboratory of Applied Chemistry Materials Science Department Mohamed Kheider University of Biskra Biskra Algeria University of Ouargla Ouargla Algeria

Perovskite PZT variants were synthesized from stoichiometric oxide ratios of Pb, Zr, Ti, Cr, Ni and Sb. The oxide powders were mixed mechanically and calcinated, and then sintered to form the desired perovskite phase. The detailed structural and ferroelectric properties were carried out for sintered specimens. The results of X-ray diffraction showed that all the ceramics specimens have a perovskite phase. The multi-component ceramic system consists of the (0.80?- x)Pb(Cr1/5,Ni1/5,Sb3/5)O3-xPbTiO3-0.20PbZrO3 (PZT-CNS), with 0.30 ≤ x ≤ 0.42, and the ternary system near the rhombohedral/tetragonal morphotropic phase boundary(MPB) was investigated by X-ray diffraction and dielectric properties. In the present system, the MPB that coexists with the tetragonal and rhombohedral phases is a narrow composition region of x = 0.38 - 0.42. The scanning Electron Microscopy (SEM) showed an increase of the mean grain size when the sintering temperature was increased. A sintered density of 92.93% of the theoretical density was obtained for Ti = 42% after sintering at 1180°C. Ceramics sintered at 1180°C with Ti = 42% achieve excellent dielectric properties, which are as follows εr = 4262.48, and Tc = 340°C.

关键词： PZT Calcination Dielectric Properties MPB Ceramic X-Ray Methods

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Investigation on the Microstructure and Electrical Properties of the Compositionally Modified PZT Ceramics Prepared by Mixed-Oxide Method

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Materials Sciences and Applications 2013年第11期4卷 723-729页

作者： Malika Abba Ahmed Boutarfaia Zelikha Necira Noura Abdessalem hayet menasra Abdelhek Meklid Laboratory of Applied Chemistry Department of Science Matter University of Biskra Biskra Algeria

The structural and electrical properties of Pb[ZrxTi0.95-x(Mo1/3In2/3)0.05]O3 piezoelectric ceramics system with the composition near the morphotropic phase boundary were investigated as a function of the Zr/Ti ratio. Studies were performed on the samples prepared by the conventional method of thermal synthesis of mixed oxides. The materials structure was investigated by X-ray diffractometry to demonstrate the co-existence of the tetragonal and rhombohedral phases. In the present system, the MPB, in which the tetragonal and rhombohedral phases coexist, is in a composition range of 0.47 ≤ x ≤ 0.50. The lattice constants of the a and c axes for the samples were calculated from the XRD patterns. Microstructure of the sintered ceramics was observed by scanning electron microscopy (SEM) of free surfaces specimens. The relative permittivity, dielectric dissipation, piezoelectric coefficient and electromechanical coupling factor reach at maximum value x = 0.49 (εr = 7300.345 (at the Curie temperature), tanδ = 0.002050, d31 = 94.965 PC/N and kp = 0.513 and a Curie temperature of 430°C). These properties are very promising for applications in ultrasonic motors.

关键词： Morphotropic Phase Boundary Sintering Temperature Zr/Ti Ratio

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Effects of Thermal Conditions in the Phase Formation of Undoped and Doped Pb(Zr1-xTix)O3Solid Solutions

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Materials Sciences and Applications 2013年第5期4卷 319-323页

作者： Zelikha Necira Ahmed Boutarfaia Malika Abba hayet menasra Nora Abdessalem Laboratory of Applied Chemistry Department of Science Matter University of Biskra Biskra Algeria Laboratory of Applied Chemistry Department of Science Matter University of Biskra Biskra Algeria University of Ouargla Ouargla Algeria

The purpose of this research is to study the effect of thermal conditions such as temperature ramp rate and isothermal times in the phase formation of Pb(Zr1-xTix)O3 solid solutions with composition near the morphotropic phase boundary (MPB) by using the conventional ceramic method. The perovskite phase formation and morphology of undoped Pb(Zr0.52Ti0.48)O3 (abbreviated PZT) and doped new material Pb0.98Gd0.02[(Zr0.52Ti0.48)0.98(Mg1/3Nb2/3)0.01(Ni1/3Sb2/3)0.01]O3 (abbreviated PZT-PGMNNS) specimens calcined between 700°C and 900°C have been examined by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared (FTIR) while the thermal evolution of the initial precursor was followed by TG-DTA. So the results of these studies have been discussed.

关键词： Pb(Zr1-xTix)O3 Morphotropic Phase Boundary Conventional Ceramic Method Perovskite Phase

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Perovskite Formation and Dielectric Responses in PZN Modified PMF-PZT Ceramics

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Journal of Chemistry and Chemical Engineering 2014年第3期8卷 250-253页

作者： Karima Bounab Zelikha Necira hayet menasra Sofiane Ameid Abdelhak Maklid Ahmed Boutarfaia Laboratory of Applied Chemistry Department of Science Matter University ofBiskra Biskra 07241 Algeria Laboratory of Semiconductor and Metal Department of Science Matter University of Biskra Biskra 07241 Algeria

PMF-PZN-PZT （0.01Pb（Mol/3Fe2/3）O3-xPb（Znl/3Nb2/3）O3-（O.99-x）P（Zro53Tio 47）03 piezoelectric ceramics）, where x = 0.00 0.01, 0.03, 0.05 and 0.07 were prepared by a conventional mixed-oxide method. The results show that the pure peroveskit phase forms in these ceramics. X-ray diffraction analysis indicated that the phase of the material is a MPB （morphotropic phase boundary） structure. The effects of PZN content on the crystal structure and electrical properties were investigated, optimal dielectric properties were achieved at composition x = 0.07 ceramics by calcination at 800 ℃ and sintering at 1,180 ℃, with a curie temperature of approximately 430 ℃. These results clearly show the significance of PZN in controlling the electrical responses of the PMF-PZN-PZT system.

关键词： Perovskit dielectric properties MPB Curie temperature.

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Biodegradation by bioaugmentation of dairy wastewater by fungal consortium on a bioreactor lab-scale and on a pilot-scale

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Journal of Environmental Sciences 2013年第9期25卷 1906-1912页

作者： hayet Djelal Abdeltif Amrane Trades School of the Environment Campus de Ker Lann35170 Bruz France European University of Brittany 5 Laennec Boulevard Rennes France University of Rennes 1 ENSCR CNRS UMR 6226 Avenue du General LeclercCS 50837 35708 Rennes Cedex 7 France

A fungal consortium including Aspergillus niger, Mucor hiemalis and Galactomyces geotrichum was tested for the treatment of dairy wastewater. The bio-augmentation method was tested at lab-scale （4 L）, at pilot scale （110 L） and at an industrial scale in Wastewater Treatment Plants （WWTP）. The positive impact of fungal addition was confirmed when fungi was beforehand accelerated by pre-culture on whey （5 g/L lactose） or on the dairy effluent. Indeed, chemical oxygen demand （COD） removal yields increased from 55% to 75% for model medium, diluted milk. While after inoculation of an industrial biological tank from a dairy factory with the fungal consortium accelerated by pre-cultivation in a 1000 L pilot plant, the outlet COD values decreased from values above the standard one （100 mg/L） to values in the range of 50-70 mg/L. In addition, there was a clear impact of fungal addition on the ＇hard＇ or non-biodegradable COD owing to the significant reduction of the increase of the COD on BOD 5 ratio between the inlet and the outlet of the biological tank of WWTP. It was in the range of 451%-1111% before adding fungal consortium, and in the range of 257%-153% after bio-augmentation with fungi. An inoculated bioreactor with fungal consortium was developed at lab-scale and demonstrated successfully at pilot scale in WWTP.

关键词： dairy wastewater biodegradation bioaugmentation fungi wastewater treatment

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Development of an Internet and Fuzzy Based Control System of Manufacturing Process

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International Journal of Automation and computing 2017年第6期14卷 706-718页

作者： Hanane Zermane hayet Mouss Laboratory of Automation and Manufacturing Industrial Engineering DepartmentBatna 2 UniversityBatna 05000Algeria

The aim of this work is to develop an Internet and fuzzy based control and data acquisition system for an industrial process plant which can ensure remote running and fuzzy control of a cement factory. Cases studies of the proposed system application in three cement factories in Algeria, SCAEK（Setif）, SCIMAT（Batna）, and SCT（Tebessa）, are discussed. The remote process control consists of alarms generated during running of the processes while maintaining and synchronizing different regulation loops thus ensuring automatic running of processes smoothly. In addition, fuzzy control of the kiln and the other two mills ensures that the system is operational at all times with minimal downtime. The process control system contains different operator station（OP）, alarms table and a provision to monitor trends analysis. The operator can execute any operation according to his authorised access assigned by the system administrator using user administration tool. The Internet technology is used for human security by avoiding all times presence of operators at site for maintenance. Further, in case of a breakdown, the problem would be remotely diagnosed and resolved avoiding requirement of an expert on site thus eliminating traveling cost, security risks, visa formalities, etc. These trips are difficult to organize（costs, visas, risks）. So the enterprise can reduce downtimes and travel costs. In order to realize a process control system guided by operators in the main control room or through Internet, the process control is based on programming in PCS 7 utilizing Cemat library and Fuzzy Control＋＋ Siemens tools.

关键词： Process control data acquisition fuzzy control networks telecontrol teleworking

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Molecular methods for colorectal cancer screening:Progress with next-generation sequencing evolution

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World Journal of Gastrointestinal Oncology 2023年第3期15卷 425-442页

作者： Salma Abbes Simone Baldi hayet Sellami Amedeo Amedei Leila Keskes Laboratory of Parasitic and Fungal Molecular Biology University of SfaxSfax 3029Tunisia Department of Experimental and Clinical Medicine University of FlorenceFlorence 50134Italy Drosophila Research Unit-Parasitology and Mycologie Laboratory University of SfaxSfax 3029Tunisia SOD of Interdisciplinary Internal Medicine Careggi University HospitalFlorence 50134Italy Laboratory of Human Molecular Genetic University of SfaxSfax 3029Tunisia

Currently,colorectal cancer(CRC)represents the third most common malignancy and the second most deadly cancer worldwide,with a higher incidence in developed *** other solid tumors,CRC is a heterogeneous genomic disease in which various alterations,such as point mutations,genomic rearrangements,gene fusions or chromosomal copy number alterations,can contribute to the disease ***,because of its orderly natural history,easily accessible onset location and high lifetime incidence,CRC is ideally suited for preventive intervention,but the many screening efforts of the last decades have been compromised by performance limitations and low penetrance of the standard screening *** advent of next-generation sequencing(NGS)has both facilitated the identification of previously unrecognized CRC features such as its relationship with gut microbial pathogens and revolutionized the speed and throughput of cataloguing CRC-related genomic ***,in this review,we summarized the several diagnostic tools used for CRC screening in the past and the present,focusing on recent NGS approaches and their revolutionary role in the identification of novel genomic CRC characteristics,the advancement of understanding the CRC carcinogenesis and the screening of clinically actionable targets for personalized medicine.

关键词： Colorectal cancer Gut microbiota Colorectal cancer screening Next-generation sequencing

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Chemical analysis,antimicrobial and anti-oxidative properties of Daucus gracilis essential oil and its mechanism of action

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Asian Pacific Journal of Tropical Biomedicine 2016年第1期6卷 8-15页

作者： Meriem El Kolli Hocine Laouer hayet El Kolli Salah Akkal Farida Sahli Laboratory of Natural Biological Resources University of Sétif 1 Laboratory of Multiphase Polymeric Materials University of Sétif 1 VARENBIOMOL: Department of Chemistry University of Constantine 1

Objective:To evaluate the essential oils(EO) composition,antimicrobial and antioxidant power of a local plant,Daucus gracilis(***).Methods:The aerial parts of *** were subjected to hydro distillation by a Clevenger apparatus type to obtain the EO which had been analyzed by gas chromatography and gas chromatography coupled with mass spectrometry,and screened for antimicrobial activity against five bacteria and three fungi by agar diffusion *** mechanism of action of the EO was determined on the susceptible strains by both of time kill assay and lysis *** minimal inhibitory concentrations were determined by agar macrodilution and micro-dilution ***-oxidative properties of the EO were also studied by free diphenyl-2-picrylhydrazyl radical scavenging and reducing power ***:The EO yielded 0.68(v/w).The chemical analysis presented two dominant constituents which were the elemicin(35.3%) and the geranyl acetate(26.8%).*** EO inhibited the growth of Bacillus cereus and Proteus mirabilis significantly with minimal inhibitory concentrations of 17.15 μg/mL by the agar dilution method and57.05 μg/mL and 114.1 μg/mL,respectively by liquid micro-dilution.A remarkable decrease in a survival rate as well as in the absorbance in 260 nm was recorded,which suggested that the cytoplasm membrane was one of the targets of the *** EO showed,also,important anti-oxidative effects with an IC50 of 0.002 mg/mL and a dosedependent reducing ***:*** EO showed potent antimicrobial and anti-oxidative activities and had acted on the cytoplasm *** activities could be exploited in the food industry for food preservation.

关键词： Daucus gracilis Apiaceae Essential oils Antimicrobial activity Macro-dilution Micro-dilution Anti-oxidative activity Reducing power

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