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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

Complexity Analysis of an Interior Point Algorithm for the Semidefinite Optimization Based on a Kernel Function with a Double Barrier Term

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Acta Mathematica Sinica,English Series 2015年第3期31卷 543-556页

作者： Mohamed ACHACHE Laboratoire de Mathématiques Fondamentales et Numériques Faculté des Sciences Université Ferhat Abbas Sétif 1Algérie

In this paper, we establish the polynomial complexity of a primal-dual path-following interior point algorithm for solving semidefinite optimization（SDO） problems. The proposed algorithm is based on a new kernel function which differs from the existing kernel functions in which it has a double barrier term. With this function we define a new search direction and also a new proximity function for analyzing its complexity. We show that if q1 〉 q2 〉 1, the algorithm has O（（q1 ＋ 1） nq1＋1/2（q1-q2）logn/ε）and O（（q1 ＋ 1）2（q1-q2）^3q1-2q2＋1√n logn/c） complexity results for large- and small-update methods, respectively.

关键词： Semidefinite optimization kernel functions primal-dual interior point methods large andsmall-update algorithms complexity of algorithms

Phosphorus Use Efficiency of Bio-Based Fertilizers:Bioavailability and Fractionation

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Pedosphere 2016年第3期26卷 310-325页

作者： Céline VANEECKHAUTE Joery JANDA Peter A.VANROLLEGHEM Filip M.G.TACK Erik MEERS Laboratory for Analytical and Applied Ecochemistry Faculty of Bioscience EngineeringGhent University model EAU Département de Génie Civil et de Génie des EauxFaculté des Sciences et de GénieUniversité Laval

Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.

关键词： chemical soil analysis digestate nutrient recovery Rhizon samplers struvite

Purification and Characterization of Cytosolic Glyceraldehyde-3-phosphate Dehydrogenase from the Dromedary Camel

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 148-154页

作者： Latifa FOURRAT,Abdelghani IDDAR,Abdelaziz SOUKRI 1Laboratoire de Physiologie et Génétique Moléculaire Département de Biologie facultédes sciences A■n-Chock UniversitéHassan-Ⅱ. Casablanca Morocco ~2Centre National de l'Energie des sciences et des Techniques Nucléaires Center d'etudes Nucléaires de la Ma■mora Rabat 10001 Morocco

Glyceraldehyde-3-phosphate dehydrogenase （GAPDH）（EC 1.***.1.12）,a key enzyme ofcarbon metabolism,was purified and characterized to homogeneity from skeletal muscle of *** protein was purified approximately 26.8 folds by conventional ammonium sulphatefractionation followed by Blue Sepharose CL-6B chromatography,and its physical and kinetic propertieswere *** native protein is a homotetramer with an apparent molecular weight of approximately146 *** focusing analysis showed the presence of only one GAPDH isoform with an isoelectricpoint of *** optimum pH of the purified enzyme was *** on the effect of temperature onenzyme activity revealed an optimal value of approximately 28-32 ℃ with activation energy of 4.9 kcal/*** apparent Kmvalues for NAD+and DL-glyceraldehyde-3-phophate were estimated to be 0.025±0.040mM and 0.21±0.08 mM, respectively. The Vmaxof the purified protein was estimated to be 52.7±5.9 U/*** kinetic parameter values were different from those described previously, reflecting protein differencesbetween species.

关键词： Camelus dromedarius glyceraldehyde-3-phosphate dehydrogenase protein purification skeletal muscle

Preservation of Juniperus thurifera L.:a rare endangered species in Algeria through in vitro regeneration

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Journal of Forestry Research 2019年第1期30卷 77-86页

作者： Nadia Khater Halima Benbouza faculté SNV Université Batna 2 Institut des sciences Vétérinaires et sciences Agronomiques Université Batna 1 Centre de Recherche en Biotechnologies

Juniperus thurifera *** an endemic Cupres saceae from the Aure`s Mountains of north eastern Algeria and endangered,in part,due to the scarcity of viable seeds It is threatened by other abiotic factors and the lack of an effective management strategy will increase its risk o *** dearth of information on its in vitro regeneration impedes its application in forest managemen *** therefore developed a micropropagation protocol using microcuttings with auxiliary *** were grown on different combinations of media supplemented with plant growth regulators at different *** highest number of shoots and branches regenerated from original shoots was obtained on Woody Plant Medium(WPM)supplemented with 6-benzylaminopurine(BAP)(0.5 mg L^(-1))and 2,4-dichlorophe noxyacetic acid(2,4-D)(0.25 mg L^(-1)).The best elongation of shoots was achieved with WPM supplemented with0.5 mg L^(-1)of BAP and 0.25 or 1 mg L^(-1) of 2,*** the second subculture,shoots had a higher number of branches than those of the *** highest rooting rate,38.8%,was obtained with shoots cultured in 1/2 Murashige and Skoog(MS)medium supplemented with 5.0 mg L^(-1)each of indol-3-butyric(IBA)and naphthalene acetic acid(NAA).Similarly,the highest root numbers and lengths were produced on 1/2 MS medium supplemented with IBA and NAA(5.0 mg L^(-1)each).During transfer to acclimatization,rates of plant losses of 50% *** second part of the experiment showed that the best shoot callusing was on WPM supplemented with BAP and 2,4-D,with either the combination 0.5+0.25 or 0.25+0.25 mg L^(-1).The results of this research provide a starting point for further studies on in vitro regeneration of *** for the sustainable management of its unique ecosystem in the Mediterranean basin.

关键词： Juniperus thurifera Callus Conservation Regeneration In vitro culture

Evaluation of androgenic activity of Zingiber officinale and Pentadiplandra brazzeana in male rats

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Asian Journal of Andrology 2002年第4期4卷 299-301页

作者： PierreKamtchouing GisèleYolandeMbongueFandio ThéophileDimo Hermine Boukeng Jatsa Laboratoire de Physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounLaboratoire de Physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounLaboratoire de Physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounDépartement de Biologie et de Physiologie Animales Faculté des Sciences Université de Douala B.P. 24157 Douala Cameroun

Aim: Aqueous extracts of Zingiber officinale and Pentadiplandra brazzeana were tested for their possible androgenic activity in male Wistar rats. Methods: The aqueous extracts of the two plants were gavaged separately to 2 groups of rats at a similar dose of 600 ***^***-1 for 8 days. At the end of the treatment, the animals were killed and the blood, testis, epididymis, seminal vesicles and prostate were collected for biochemical analysis. Results: The aqueous extract of Z. officinale significantly increased in the relative weight of the testis, the serum testosterone level, testicular cholesterol level and epididymal α-glucosidase activity. The aqueous extract of P. brazzeana significantly increased the weights of the testis, seminal vesicles and prostate. It also significantly increased the serum and testicular testosterone level. The fructose, α-glucosidase and cholesterol levels in P. brazzeanatreated rats were increased by 28%, 35% and 114%, respectively. Conclusion: The aqueous extracts of both P. brazzeana and Z. officinale have an androgenic activity, which seems to be more potent with P. brazzeana than with Z. officinale. (Asian J Androl 2002 Dec; 4: 299-301)

关键词： P. brazzeana Z. officinale testosterone androgenic activity

Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

Numerical simulation of the effect of the free carrier motilities on light-soaked a-Si:H p–i–n solar cell

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Journal of Semiconductors 2015年第7期36卷 59-68页

作者： L.Ayat A.F.Bouhdjar AF.Meftah N.Sengouga Laboratory of Semiconductor Devices Physics Physics DepartmentUniversity of Béchar faculté des sciences de la matière Laboratoire des Matériaux Semi-conducteurs et MétalliquesUniversité Mohammed Khider

Using a previous model, which was developed to describe the light-induced creation ofthe defect density in the a-Si：H gap states, we present in this work a computer simulation of the a-Si：H p-i-n solar cell behavior under continuous illumination. We have considered the simple case of a monochromatic light beam nonuniformly absorbed. As a consequence of this light-absorption profile, the increase of the dangling bond density is assumed to be inhomogeneous over the intrinsic layer （i-layer）. We investigate the internal variable profiles during illumination to understand in more detail the changes resulting from the light-induced degradation effect. Changes in the cell external parameters including the open circuit voltage, Voc, the short circuit current density, Jsc, the fill factor, FF, and the maximum power density, Pmax, are also presented. This shows, in addition, the free carrier mobility influence. The obtained results show that Voc seems to be the less affected parameter by the light-induced increase of the dangling bond density. Moreover, its degradation is very weak-sensitive to the free carrier mobility. Finally, the free hole mobility effect is found to be more important than that of electrons in the improvement of the solar cell performance.

关键词： a-Si:H Staebler-Wronski effect defect pool model p-i-n

Exact solution of the one-dimensional Klein-Gordon equation with scalar and vector linear potentials in the presence of a minimal length

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Chinese Physics B 2010年第2期19卷 43-47页

作者： Y Chargui L Chetouani A Trabelsi Unit de Recherche de Physique Nuclaire et des Hautes Energies Facult des Sciences de Tunis Dpartement de Physique Thorique Institut de PhysiqueUniversit de ConstantineRoute Ain El BeyConstantineAlgeria Centre National des sciences et Technologies Nuclaires Technopole de Sidi-Thabet 2020Tunisia

Using the momentum space representation, we solve the Klein--Gordon equation in one spatial dimension for the case of mixed scalar and vector linear potentials in the context of deformed quantum mechanics characterized by a finite minimal uncertainty in position. The expressions of bound state energies and the associated wave functions are exactly obtained.

关键词： Klein--Gordon equation linear potential minimal length exact solution

Existence of T-solution for Degenerated Problem via Minty's Lemma

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Acta Mathematica Sinica,English Series 2008年第3期24卷 431-438页

作者： Y.AKDIME E.AZROUL M.RHOUDAF Département de Mathématiques et Informatique facultédes sciences Dhar-Mahraz B. P 1796 Atlas Fès Maroc

We study the existence result of solutions for the nonlinear degenerated elliptic problem of the form, -div（a（x, u,△↓u）） = F in Ω, where Ω is a bounded domain of R^N, N≥2, a ：Ω×R×R^N→R^N is a Carathéodory function satisfying the natural growth condition and the coercivity condition, but they verify only the large monotonicity. The second term F belongs to W^-1,p′（Ω, w^＊）. The existence result is proved by using the L^1-version of Minty＇s lemma.

关键词： weighted Sobolev spaces truncations L^1-version of Minty's lemma