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Fluoride Hydro-geochemistry Studies:A Case Study from Granitic Aquifer System of Maheshwaram,Hyderabad,India

地学前缘 2009年第S1期16卷 11-12页

作者： Surendra Atal Hélène Pauwels Jean-Marie Gandolfi Shakeel Ahmed National Geophysical research Institute(CSIr) BrGM 3 Avenue Claude Guillemin 45060 Orleans IFCGr National Geophysical Research Institute(CSIR)

The impact of population pressure has been observed on several systems,groundwater resource is one among *** and over-exploitation has not only caused the decline of groundwater levels but also causes deterioration in... 详细信息

关键词： fluor.ne hydro-geochemistry granites hard rock aquifer

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Physicochemical and Mechanical Performances of Technical Flax Fibers and Biobased Composite Material: Effects of Flax Transformation Process

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Journal of r.newable Materials 2019年第9期7卷 821-838页

作者： M.Khennache A.Mahieu M.ragoubi S.Taibi C.Poilâne N.Leblanc UniLaSalle Unitéde recherche Transformations&Agro-RessourcesVAM^(2)IN(EA 7519 UniLaSalle-Universitéd’Artois)Mont Saint AignanFrance Normandie University 14032 CaenFrance UNICAEN CIMAP14032 CaenFrance ENSICAEN 14050 CaenFrance CEA UMR625214070 CaenFrance and CNrS UMr6252 14050 CaenFrance

In France,the use of flax fibers as reinforcement in composite materials is growing exponentially in the automotive sector,thanks to their good physicochemical properties,environmental reasons,health neutrality and due to the European Council Directives on the reuse,recycling and valorization of car components and *** aim of our study is to investigate biochemical,physicochemical,and mechanical properties of technical flax fibers to evaluate the impact of transformation processes(scutching,hackling,and homogenization)on final properties of associated composite *** chemical analysis such as Van Soest(biochemical fraction measurement),FTIr(Fourier Transform Infrared spectroscopy),and XrD(X-ray diffraction)were carried out on different process modalities and show that there is no significant difference in terms of biochemical fraction and crystallinity *** the same token,mechanical behavior shows that Young’s modulus is not affected by the transformation *** result is also observed for thermal *** results highlight the fact that the transformation processes of technical fibers do not really affect their physicochemical and mechanical performances.

关键词： Technical flax physicochemical properties processes composite

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Contamination,Fractionation and Availability of Metals in Urban Soils in the Vicinity of Former Lead and Zinc Smelters,France

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Pedosphere 2013年第2期23卷 143-159页

作者： C.WATErLOT G.BIDAr A.PELFr.ne H.rOUSSEL H.FOUrrIEr F.DOUAY Université Lille Nord de France Groupe ISA Equipe Sols et Environnement Laboratoire Génie Civil et géoEnvironnement (LGCgE) Lille Nord de France (EA 4515) Département des Sites et Sols Pollués Agence de I'Environment et de la Matrise de I'Energie (ADEME)

Soil contamination by metals from anthropogenic activities （e.g., mining and smelting） is a major concern for the environment and human health. Environmental availability of cadmium （Cd）, lead （Pb）, zinc （Zn）, copper （Cu）, and indium （In） in 27 urban soils located around two former Pb and Zn smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry （FAAS or ETAAS）, depending on their concentration levels. After optimisation of the ETAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical procedure. Metal partitioning was conducted using a four-step sequential extraction procedure. The results showed that Cd and Zn were mainly in the acid-extractable and reducible forms in the urban soils studied. In contrast, Pb and In were largely in the reducible fraction. However, in some samples, the amount of In extracted in the residual or exchangeable fraction was higher than that in the reducible fraction. Copper was mainly found in the reducible and residual fractions. A pot experiment was conducted in a glasshouse with seven soils （six contaminated and one uncontaminated） and two plant species, ryegrass and lettuce. The results showed transfer of metals from the contaminated soils to the shoots of ryegrass and the edible part of lettuce. The metal bioconcentration factor was in the order of Cd 〉〉 Cu 〉 In 〉 Zn 〉〉 Pb for lettuce leaves, whereas for ryegrass shoots, three orders were found, Cd 〉 Zn 〉 Cu 〉〉 In 〉 Pb, Cd 〉〉 In 〉 Zn 〉 Cu 〉〉Pb, and Zn 〉 Cd 〉 Cu 〉 In 〉〉 Pb, depending on the physico-chemical properties of the soils, such as pH, cation exchange capacity, carbonates, and organic matter. It was established that the metal toxicity was related to the contamination levels and the physico-chemical properties, including pH, organi

关键词： bioconcentration factor environmental availability metal toxicity sequential extraction soil physico-chemical property

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Global Transmission Dynamics of a Schistosomiasis Model and Its Optimal Control

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Applied Mathematics 2019年第6期10卷 397-418页

作者： Mouhamadou Diaby Mariama Sène Abdou Sène Laboratoire d’Analyse Numérique et d’Informatique (LANI) UFR SAT Université Gaston Berger de Saint-Louis Saint-Louis Sénégal UFr AGrO Université Gaston Berger de Saint-Louis Saint-Louis Sénégal LANI P&ocirc le STN MAI (Mathématiques Appliquées et Informatique) Université Virtuelle du SENEGAL Dakar-Fann Sénégal

Drug treatment, snail control, cercariae control, improved sanitation and health education are the effective strategies which are used to control the schistosomiasis. In this paper, we consider a deterministic model for schistosomiasis transmission dynamics in order to explore the role of the several control strategies. The global stability of a schistosomiasis infection model that involves mating structure including male schistosomes, female schistosomes, paired schistosomes and snails is studied by constructing appropriate Lyapunov functions. We derive the basic reproduction number r0 for the deterministic model, and establish that the global dynamics are completely determined by the values of r0. We show that the disease can be eradicated when r0?≤1;otherwise, the system is persistent. In the case where ?r0?>1, we prove the existence, uniqueness and global asymptotic stability of an endemic steady state. Sensitivity analysis and simulations are carried out in order to determine the relative importance of different control strategies for disease transmission and prevalence. next, optimal control theory is applied to investigate the control strategies for eliminating schistosomiasis using time dependent controls. The characterization of the optimal control is carried out via the Pontryagins Maximum Principle. The simulation results demonstrate that the insecticide is important in the control of schistosomiasis.

关键词： Schistosomiasis Models Nonlinear Dynamical Systems Global Stability reproduction Number Optimal Control Sensitivity Analysis

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Transit time ultrasound perivascular flow probe technology is superior to Mr imaging on hepatic blood flow measurement in a porcine model

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 538-545页

作者： Mohamed Bekheit Chloe Audebert Petru Bucur Hans Adriaensen Emilie Bled Mylène Wartenberg Ir.ne Vignon-Clementel Eric Vibert Inserm Unité 1193 112 Boulevard Paul Valliant CuturierVillejuifFrance Institute of medical sciences University of AberdeenAberdeenUK Centre de recherche Inria de Paris ParisFrance Sorbonne Universités UPMC University of Paris 6Laboratoire Jacques-LouisLionsParisFrance CHrU hopitaux de ToursChirurgie Héato-biliaire et pancréatiqueTransplantation HéatiqueToursFrance Plateforme Chirurgie et Imagerie pour le recherche et l’Enseignement(CIrE) ImagerieUMR-PRC37380 NouzillyCentre INRA Val de LoireFrance AP-HP Hoital Paul BrousseCentre Héato-BiliaireVillejuifFrance

Background: The hepatic hemodynamics is an essential parameter in surgical planning as well as in various disease processes. The transit time ultrasound(TTUS) perivascular flow probe technology is widely used in clinical practice to evaluate the hepatic inflow, yet invasive. The phase-contrast-MrI(PC-MrI) is not invasive and potentially applicable in assessing the hepatic blood flow. In the present study, we compared the hepatic inflow rates using the PC-MrI and the TTUS probe, and evaluated their predictive value of post-hepatectomy adverse events. Methods: Eighteen large white pigs were anaesthetized for PC-MrI and approximately 75% hepatic resection was performed under a unified protocol. The blood flow was measured in the hepatic artery(Qha), the portal vein(Qpv), and the aorta above the celiac trunk(Qca) using PC-MrI, and was compared to the TTUS probe. The Bland-Altman method was conducted and a partial least squares regression(PLS) model was implemented. results: The mean Qpv measured in PC-MrI was 0.55 ± 0.12 L/min, and in the TTUS probe was 0.74 ± 0.17 L/min. Qca was 1.40 ± 0.47 L/min in the PC-MrI and 2.00 ± 0.60 L/min in the TTUS probe. Qha was 0.17 ± 0.10 L/min in the PC-MrI, and 0.13 ± 0.06 L/min in the TTUS probe. The Bland-Altman method revealed that the estimated bias of Qca in the PC-MrI was 32%(95% CI:-49% to 15%); Qha 17%(95% CI:-15% to 51%); and Qpv 40%(95% CI:-62% to 18%). The TTUS probe had a higher weight in predicting adverse outcomes after 75% resection compared to the PC-MrI( β= 0.35 and 0.43 vs β = 0.22 and 0.07, for tissue changes and premature death, respectively). Conclusions: There is a tendency of the PC-MrI to underestimate the flow measured by the TTUS probes. The TTUS probe measures are more predictive of relevant post-hepatectomy outcomes.

关键词： Hepatic blood flow Phase contrast MrI Transit time ultrasound probe Porcine model Liver surgery

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