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Porous media grain size distribution and hydrodynamic forces effects on transport and deposition of suspended particles

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Journal of Environmental Sciences 2017年第3期29卷 161-172页

作者： Nasre-Dine Ahfir Ahmed Hammadi Abdellah Alem HuaQing Wang gilbert le bras Tariq Ouahbi Normandie University UNIHAVREUMR 6294 CNRSLOMC76600 Le HavreFrance GeM UMR 6183 CNRSUniuersite de NantesBP 42044606 Saint Nazaire CedexFrance

The effects of porous media grain size distribution on the transport and deposition of polydisperse suspended particles under different flow velocities were investigated. Selected Kaolinite particles （2-30 μm） and Fluorescein （dissolved tracer） were injected in the porous media by step input injection technique. Three sands filled columns were used： Fine sand, Coarse sand, and a third sand （Mixture） obtained by mixing the two last sands in equal weight proportion. The porous media performance on the particle removal was evaluated by analysing particles breakthrough curves, hydro-dispersive parameters determined using the analytical solution of convection-dispersion equation with a first order deposition kinetics, particles deposition profiles, and particle-size distribution of the recovered and the deposited particles. The deposition kinetics and the longitudinal hydrodynamic dispersion coefficients are controlled by the porous media grain size distribution. Mixture sand is more dispersive than Fine and Coarse sands. More the uniformity coefficient of the porous medium is large, higher is the filtration efficiency. At low velocities, porous media capture all sizes of suspended particles injected with larger ones mainly captured at the entrance. A high flow velocity carries the particles deeper into the porous media, producing more gradual changes in the deposition profile. The median diameter of the deposited particles at different depth increases with flow velocity. The large grain size distribution leads to build narrow pores enhancing the deposition of the particles by straining.

关键词： Suspended particlesPorous mediaGrain size distributionStructured heterogeneityStrainingParticle size distribution

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SEDIMENTATION AND CONSOLIDATION OF A HIGH WATER CONTENT SOIL

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International Journal of Sediment Research 2000年第3期15卷 269-276页

作者： AleXIS Alain, le bras gilbert Researcher, Laboratoire de Genie Civil de Names Saint-Nazaire, IUT de Saint-Nazaire, Saint Nazaire,France PHD Student, Laboratoire de Genie Civil de Names Saint-Nazaire, IUT de Saint-Nazaire, Saint Nazaire,France Tel. 00 33 Lab. de Genie Civ. de Nantes IUT de Saint-Nazaire Saint Nazaire France

The permanent siltation of harbours and estuaries has led their administrative companies to undertake dredging operations in order to guarantee a minimal water depth required for free access to port infrastructures. This long and expensive work interferes with the port trade. Dredged material is injected into the sea with the creation of a maritime dump or stocked on earth in basins. In each case, there will be a formation of a high water content soil. This paper deals with the geotechnical formation of high water content soils by means of an experimental laboratory sedimentation/consolidation bench. We have devised and realized a controlled bench which allows us to analyze the natural soil formation under self weight. The tested soil settles in sedimentation/consolidation columns (1.5 m. in height, 100 mm in diameter). Pressure and density measurements in the tested soil are possible on the whole height of the vertical column. Values of density are obtained by gamma-densimetry. The precision of the measurements is +/-0.5% for the density and +/-3 Pa for the pressures. Each test is performed over 32 days with 17 intermediate times. An originality of this bench lies in the fact that it allows measurements with a good precision in density and pressure at a very early state of soil formation (first values at 1 .33 min. from the beginning of the test). The test we are presenting concerned the natural mud found in the Loire estuary (France) prepared to an initial concentration of 200 g/ 1 (density 1. 135). These measurements are studied in terms of evolution of total stress, excess pore pressure, void ratio and effective stress as related to time. For this test, we present the density and pressure measured profiles as well as the deduced effective stress curves, paths of particles and rates of consolidation. On a void ratio versus effective stress diagram, we clearly show the evolution of soil consolidating under self weight during the intermediate phase of its formation

关键词： High water content soils Sedimentation/consolidation Density Pore pressure Effective stress Particle trajectory.

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Assessment of Policies, Laws, and Regulations Affecting the Contraceptive Needs of Adolescents in the Democratic Republic of the Congo

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Health 2020年第9期12卷 1241-1261页

作者： Dieudonné Mpunga Mukendi Eric Mafuta Musalu Fidèle Mbadu Muanda Guy-Octave Lutumba Faustin Chenge Mukalenge Mala Ali Mapatano gilbert Wembodinga Utshudienyema School of Public Health of Kinshasa University of Kinshasa Kinshasa Democratic Republic of the Congo National Program for Adolescent Health Ministry of Public Health Democratic Republic of the Congo Faculty of Law University of Kinshasa Kinshasa Democratic Republic of the Congo School of Public Health of Lubumbashi University of Lubumbashi Lubumbashi Democratic Republic of the Congo

Background: Poor regulation is a barrier to adolescents’ accessing family planning (FP) services. We aimed to assess policies, laws, and regulations according to the contraceptive needs of adolescents in the Democratic Republic of the Congo (DRC). Methods: A mixed method study was conducted in 74 structures, including 13 administrative structures and 61 facilities offering FP. Data were collected through semi-structured interviews and document review. Using a health policy analysis framework, we analyzed the types of policies;their availability at the delivery points;the actors and the context of the policy formulation process. The content of policies was analyzed on the basis of WHO recommendations to ensure respect for human rights in the provision of contraceptive information and services. Results: Of the policies targeting the sexual and reproductive health (SRH), 18 were mainly focused on the FP of which 5 were the standards and directives;5 implementing documents;3 guidelines;3 laws and 2 policies. Twelve documents were classified “important” for the FP extension. However, a few targeted adolescents and were translated into operational instructions for providers. Of 9 WHO recommendations, one was fully and two partially integrated into FP policies. Adolescents and FP providers were less involved in the policy formulation process. Conclusion: The FP regulation remains problematic in the DRC. FP policies are unsuitable to adolescents’ expectation;they do not guarantee a secure and unrestricted access to FP services. The ministry of health should put in place evidence-based regulations to improve access to SRH services by adolescents.

关键词： Policies Family Planning Needs Adolescents

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5 octobre 1961,création de la Délégation générale du Québec  Paris

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法语学习 2012年第4期 59-63页

作者： gilbert Pilleul 蓝霸 Secrétaire général de la CFQLMC-France

Dans la mémoire collective,le souvenir du《Vive le Québec libre!》2 prononcé par legénéral de Gaulle,du balcon de l'htel de ville de Montréal,occulte 3 en partie voire totalement la place que le Québec ou le

关键词：法语学习学习方法阅读知识阅读材料

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Stroke in type 2 diabetes mellitus patients admitted to emergency unit in Central African country (Congo): Preliminary findings

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Journal of Diabetes Mellitus 2013年第4期3卷 208-213页

作者： Bertrand Fikahem Ellenga-Mbolla Henri Germain Monabeka Paul Macaire Ossou-Nguiet gilbert Fabrice Otiobanda Kryste Chancel Mahoungou Guimbi Thierry Raoul Gombet Suzy-Gisèle Kimbally-Kaky Benjamin Longo Mbenza Department of Cardiology University Hospital of Brazzaville Brazzaville Congo Department of Medicine Faculty of Health Sciences Marien Ngouabi University Brazzaville Congo Faculty of Health Sciences Walter Sisulu University Mthatha South Africa Intensive Care Unit University Hospital of Brazzaville Brazzaville Congo

Background: The cardiovascular risk factors including type 2 diabetes mellitus (T2DM) are a public health problem in sub-Saharan Africa. The aim of this study is to determine the prevalence and factors associated with stroke in T2DM patients admitted to the emergency Unit in Brazzaville. Patients and Methods: This is the preliminary findings of a cross-sectional study including patients with T2DM, admitted in Emergency Unit of University Hospital of Brazzaville from January to April 2011. One hundred and seven patients were included. Sex ratio was 1.5. Results: The mean age was 60.3 ± 10.2 years (range 40 - 80 years). Stroke story was noted in 5 cases (4.6%). The main pathologies were metabolic complications (n = 51;47.6%) and cardiovascular diseases (n = 36;33.6%), dominated by stroke (17 cases). Epidemiological factors associated with stroke were high standard living (OR = 3, 95% CI: 1.02 - 8.9, p = 0.03), polypharmacy (OR = 3.7, 95% CI: 1.27 - 10.8, p = 0.01), previous hospitalization (OR = 3.1, 95% CI: 1.07 - 8.9, p = 0.03), and the absence of antiplatelet therapy (OR = 4.2, 95% CI 1.2 to 15, p = 0.03). Clinical associated factors were coma (OR = 3.3, 95% CI 1.14 to 9.6, p = 0.02) and the presence of severe hypertension (OR = 4, 95% CI: 1.2 - 12, p = 0.02). Finally, prognostic factors were the transfer in intensive care unit (OR = 9.8, 95% CI: 2.7 - 34, p 0.001). Conclusion: The first cardiovascular complication in patients with T2DM admitted in emergency at University Hospital of Brazzaville is stroke. Primary prevention in high-risk patients is still inadequate.

关键词： Type 2 Diabetes Mellitus Stroke Emergency Brazzaville

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Endovascular Repair of an Infected Broken Pseudoaneurysm of the Extracranial Internal Carotid Artery

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Open Journal of Radiology 2012年第4期2卷 113-116页

作者： Claude Michel Alain Parot Patrick Jue Denis Pierre-Yves Laffy Jean-Yves Riou gilbert leblanc Cardio-Vascular Radiology Department Marie Lannelongue Hospital Le Plessis Robinson France Vascular Radiology Department Europe Medico-Surgical Center Le Port Marly France Vascular Surgery Department Europe Medico-Surgical Center Le Port Marly France

The formation of pseudoaneurysms after carotid endarterectomy is extremely rare. Treating those pseudoaneuryms is necessary because of the risks for continued expansion, rupture and distal embolism. Traditional surgical repair of carotid artery pseudoaneurysms is associated with a high morbidity and mortality. An endovascular approach to these infected pseudoaneurysms limits the risk for operative damage to surrounding structures and potential blood loss.

关键词： Carotid Artery Pseudoaneurysm Covered Self Expandable Stent

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了解魁北克历史的15个关键词

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法语学习 2010年第4期 79-84页

作者： gilbert Pilleul 李洪峰

Nouvelle-France 新法兰西 Cartier1 la 《 découvre 》 en 1534,Champlain2 y fonde Québec en *** Nouvelle-France, son apogée,avec le Canada,l'Acadie3,Terre-Neuve4 et la Louisiane jusqu'aux Grands lacs5,s'étendait d... 详细信息

关键词：魁北克加拿大下加拿大加拿大东区平静革命

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Modeling the Distribution of Marketable Timber Products of Private Teak(Tectona grandis L.f.)Plantations

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Open Journal of Forestry 2013年第4期3卷 115-121页

作者： Noel H.Fonton gilbert Atindogbe Arcadius Y.Akossou Brice T.Missanon Belarmain Fadohan Philippe lejeune Laboratory of Study and Research in Applied Statistics and Biometry University of Abomey-CalaviAbomey-CalaviBenin Faculty of Agronomy University of ParakouParakouBenin Unit of Forest and Nature Management Gembloux Agro-Bio TechUniversity of LiegeGemblouxBelgium

Management of marketable products of private plantations will not be sustainable without class girth being identifiable readily. Modeling marketable products is a key to obtain good fitness between observed and theoretical girth distribution. We determine the best parameter recovery method with the Weibull function for two sylvicultural regimes (coppice and high forest). Data on stand variables were collected from 1101 sample plots. The three Weibull function parameters were estimated with three parameters recovery methods: the maximum likelihood method, the method of moments and the method of percentiles. Stepwise regression and the simultaneously re-estimated parameter using the Seemingly Unrelated Regression Estimation were applied to model each parameter. The results indicated that the three methods successfully predicted girth size distributions within the sample stands. The method of moments was the best one with lowest values of Reynolds error index and Kolmogorov-Smirnov statistic however the sylvicultural regimes. The Weibull parameter distribution model developed for each of the two sylvicultural regimes was quite reliable.

关键词： Weibull Parameter Recovery Method Reynolds Index Sylvicultural Regime Poles Logs

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Adhoc中基于主动网的自适应FEC

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电子科技大学学报 2006年第5期35卷 733-735,773页

作者：陈玉王晟李乐民电子科技大学通信与信息工程学院成都610054

针对无线信道中高误码率限制传输性能,固定前向纠错(FEC)又不能适应无线网络中误码率多变和链路差异的环境等问题,通过利用主动网的网络可编程接口在Adhoc网络中动态地实现了一种跳到跳的自适应前向纠错策略,并采用仿真实验进行性能分析... 详细信息

针对无线信道中高误码率限制传输性能,固定前向纠错(FEC)又不能适应无线网络中误码率多变和链路差异的环境等问题,通过利用主动网的网络可编程接口在Adhoc网络中动态地实现了一种跳到跳的自适应前向纠错策略,并采用仿真实验进行性能分析,结果表明能对上述原因造成的丢包起到很好的改善作用。

关键词：误码率 Ad hoc网络跳到跳自适应前向纠错主动网

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基于反铁磁的无外场辅助自旋轨道矩磁隧道结模型分析

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物理学报 2023年第19期72卷 299-308页

作者：王可欣粟傈童良乐首都师范大学信息工程学院北京100048

自旋轨道转矩(spin-orbit torque,SOT)为超低功耗自旋电子器件提供新的实现方法,在反铁磁材料体系中面内交换偏置场可辅助SOT磁化翻转,同时利用电压调控磁各向异性(voltage-controlled magnetic anisotropy,VCMA)能有效降低翻转势垒,从... 详细信息

自旋轨道转矩(spin-orbit torque,SOT)为超低功耗自旋电子器件提供新的实现方法,在反铁磁材料体系中面内交换偏置场可辅助SOT磁化翻转,同时利用电压调控磁各向异性(voltage-controlled magnetic anisotropy,VCMA)能有效降低翻转势垒,从而实现无外场辅助的磁隧道结.本文通过求解修正LandauLifshitz-gilbert(LLG)方程,建立反铁磁/铁磁/氧化物构成的无外场辅助自旋轨道矩的磁隧道结模型,并对其磁化动力学过程进行分析.以IrMn/CoFeB/MgO材料体系为例,揭示了影响磁化翻转的因素,包括交换偏置(exchange bias,EB)效应对临界翻转电流ISOT的影响,VCMA效应和SOT类场转矩的影响机制;分析了实际应用中磁隧道结制作工艺偏差的影响.结果表明:EB效应与VCMA效应共同作用能极大降低临界翻转电流ISOT,从而实现完全无场开关切换;SOT类场转矩对磁化翻转起主导作用,且一定条件下可实现器件在ps量级的无场翻转;以及当氧化层厚度偏差γtf?10%或自由层厚度偏差γtox?13%时MTJ能实现有效切换.基于反铁磁的无场辅助自旋轨道矩器件将为新一代超低功耗、超高速度和超高集成度器件和电路提供极具前景的解决方案.

关键词：自旋轨道矩磁隧道结压控磁各向异性交换偏置工艺偏差

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