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Field investigation on friction factor in mountainous cobble-bed and boulder-bed rivers

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International Journal of Sediment Research 2011年第2期26卷 210-221页

作者： Hossein AFZALIMEHR jacques GALLICHAND Ehsan BAGHERI Department of Water Engineering Isfahan University of Technology Departement des sols et de genie agroalimentaire Universite Laval Water Engineering Department Isfahan University of Technology

This paper presents results of the friction factor of cobble-bed and boulder-bed rivers based on 23 field measurements in three mountainous rivers in *** reveal that features of our measured velocity profiles in boulder-bed rivers in mountainous region do not present a specific shape but illustrate specific pattern in cobble-bed *** difference is attributed to scale effect of relative submergence. It is found that the relative submergence in cobble and boulders-bed rivers is the only key parameter that influences friction factor estimation and other parameters such as particle Froude number and Froude number have few impacts on flow resistance of cobble-bed and boulder-bed *** proposed relationship for estimation for the friction factor should be useful for large coarse-bed rivers.

关键词： Boulder-bed Cobble-bed Friction factor Mountainous river Relative submergence

Investigation of turbulence characteristics in channel with dense vegetation

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International Journal of Sediment Research 2011年第3期26卷 269-280+282+281页

作者： Hossein AFZALIMEHR Razieh MOGHBEL jacques GALLICHAND Water Engineering Department Isfahan University of TechnologyIran 84156 Departement des sols et de genie agroalimentaire Universite LavalSt-FoyQcCanada

In this experimental study,the turbulent flow in a channel with vegetation by using sprouts of wheat on channel bed was *** different aspect ratios of channel were *** Acoustic Doppler Velocimetry was used to measure parameters of turbulent flow over submerged sprouts of wheat,such as velocity *** log law and the Reynolds shear stress distribution were applied. Results indicate that the position of the maximum turbulence intensity superposes on the inflection point situated over the top of submerged vegetation *** analysis shows that near the vegetation bed,the sweeps and ejections appear to be the most dominant phenomenon,while far from the vegetated bed,the outward is dominant *** also show that the aspect ratio plays an important role on the contribution of the different bursting events for Reynolds stress determination.

关键词： Bed vegetation Aspect ratio Reynolds stress Quadrant analysis

Modelling and mathematical results arising from ferromagnetic problems

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Science China Mathematics 2012年第5期55卷 1053-1067页

作者： DESCLOUX Jean FLUECK Michel RAPPAZ jacques Department of Mathematics Ecole Polytechnique Fdrale de Lausanne (EPFL)Lausanne 1015Switzerland

Abstract In this article, we investigate the equations of magnetostaties for a configuration where a ferromagnetic material occupies a bounded domain and is surrounded by vacuum. Furthermore, the ferromagnetic law takes the form B=μ0μr（｜H｜）Hi i.e., the magnetizing field H and the magnetic induction B are collinear, but the relative permeability μr is allowed to depend on the modulus of H. We prove the well-posedness of the magnetostatic problem under suitable convexity assumptions, and the convergence of several iterative methods, both for the original problem set in the Beppo-Levi space W1（R3）, and for a finite-dimensional approximation. The theoretical results are illustrated by numerical examples, which capture the known physical phenomena.

关键词： ferromagnetism nonlinear elliptic problems finite element methods optimisation algorithms

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Heat Transfer Model with Two Heat Transfer Coefficients Along a M ultiperforated Plate-Application to Combustion Chamber Wall Cooling

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Journal of Thermal Science 2003年第4期12卷 363-366页

作者： Brice Petre Eva Dorignac Jean jacques Vullierme Laboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCE

Walls' cooling of aeronautic propeller combustion chamber is performed with the injection, through the combustion chamber wall, of a part of the air coming from compressors placed upstream. Measurements of the wall thermal fields are made by infrared thermography along the injection wall. This injection wall is pierced by 9 rows of 8 holes (α=90°) in staggered configuration (p/D=s/D=6). We propose a model using two heat transfer coefficients to represent the convective exchanges. The results are non-dimensioned and presented in comparison with the case without holes. The use of this model allows us to define 4 zones. Those 4 zones exist for the 5 blowing rates.

关键词： multiperforation cooling heat transfer coefficients infrared thermography.

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CO_2,carbonate-rich melts,and brines in the mantle

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Geoscience Frontiers 2014年第5期5卷 697-710页

作者： Maria-Luce Frezzotti jacques L.R.Touret Department of Earth and Environmental Sciences University Milano Bicocca.P.za Della Scienza 4.20126 Milano.Italy Mineralogy Universite Pierre et Marie Curie4 Place Jussieu 75272 Paris Cedex 05France

This paper reviews the origin and evolution of fluid inclusions in ultramaflc xenoliths, providing a framework for interpreting the chemistry of mantle fluids in the different geodynamic settings. Fluid inclusion data show that in the shallow mantle, at depths below about 100 km, the dominant fluid phase is CO2 ± brines, changing to alkali-, carbonate-rich （silicate） melts at higher pressures. Major solutes in aqueous fluids are chlorides, silica and alkalis （saline brines; 5-50 wt.% NaCl eq.）. Fluid inclusions in peridotites record CO2 fluxing from reacting metasomatic carbonate-rich melts at high pressures, and suggest significant upper-mantle carbon outgassing over time. Mantle-derived CO2 （±brines） may eventually reach upper-crustal levels, including the atmosphere, independently from, and additionally to magma degassing in active volcanoes.

关键词： Fluid inclusionPeridotiteMantle metasomatismCarbonate-rich meltCO2Saline brine

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The Dynamics of the Nucleation, Growth and Termination of Single-Walled Carbon Nanotubes from in situ Raman Spectroscopy During Chemical Vapor Deposition

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Nano Research 2009年第10期2卷 783-792页

作者： Paul Finnie Andrew Li-Pook-Than jacques Lefebvre Institute for Microstructural Sciences National Research Council CanadaBuilding M-501200 Montreal RoadOttawaONK1A 0R6Canada Department of Physics University of Ottawa150 Louis PasteurOttawaON K1N 6N5Canada

The dynamics of the chemical vapor deposition(CVD)of single-walled carbon nanotubes(SWNTs)is extracted experimentally using in situ Raman *** are grown using a thinlm cobalt catalyst and an ethanol precursor in a miniature hot walled reactor with optical *** spectra at room temperature and at the growth temperature are compared for two growth *** evolution of the G-band,D-band,and radial breathing mode(RBM)is tracked at the growth temperature with time resolution of a few *** are three identifiable phases in the evolution of the Raman signal intensity:an initial exponential increasing phase,a linear growth phase,and a saturation *** situ optical spectroscopy thus enables the study of nucleation,steady growth,and deactivation processes to be investigated separately in real *** evolution curves for all bands(G,D,and RBM),when scaled,collapse onto the same curve,to within experimental uncertainty.

关键词： Single-walled carbon nanotube chemical vapor deposition Raman spectroscopy nucleation termination

Geological applications using geospatial standards-an example from OneGeology-Europe and GeoSciML

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International Journal of Digital Earth 2010年第S1期3卷 31-49页

作者： John Laxton Jean-jacques Serrano Agnes Tellez-Arenas British Geological Survey Murchison HouseWest Main Rd.Edinburgh EH93LAUK BRGM 3 Avenue Claude-GuilleminBP 36009Orleans 45060France

The Geoscience Markup Language(GeoSciML)has been developed to enable the interchange of geoscience information,principally that portrayed on geological maps as well as boreholes.A GeoSciML testbed was developed both to test the implementation of the data model and its application in web *** OneGeology-Europe project aims to use the GeoSciML data model,and build on the experience of the GeoSciML testbed,in implementing a geoportal for a harmonised geological map of Europe at 1:1 million *** involves the integration of web services from 20 participating *** important objective of OneGeology-Europe is to contribute to Infrastructure for Spatial Information in the European Community(INSPIRE),both through the development of a geological data specification and the use of the INSPIRE technical *** and the OneGeology-Europe project are also steps towards incorporating geoscience data into a Digital *** the development of GeoSciML and the implementation of web services for GeoSciML and OneGeology-Europe,have followed a standards-based *** technical architecture comprises a geoportal providing access to a Catalogue Service for the Web for metadata describing both the data and services ***-Europe will provide bothWeb Map Services view andWeb Feature Services download services,which aim to be compliant with the INSPIRE implementing rules.

关键词： data exchange model web services spatial data standards INSPIRE digital earth geoinformatics geology

Analysis of forestry impacts and biodiversity in two Pyrenean forests through a comparison of moth communities （Lepidoptera, Heterocera）

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Insect Science 2007年第4期14卷 323-338页

作者： CARINE LUOUE CHARLES GERS jacques LAUGA NESTOR MARIANO Laboratoire Dynamique de la Biodiversit6 UMR5172CNRS/Universit6Paul SabatierToulouseFrance Institut fur Pharmazie und Molekulare Biotechnologie-Abteilung Biologie Universitat HeidelbergHeidelbergGermany Evolution et Diversit6Biologique UMR 5174 CNRS/Universit6 Paul SabatierToulouseFrance CEAMISH-Universidad Aumnoma EstadoMorelos CuemavacaMorelosCP:62210 Mexico

We have compared the biodiversity variations in moth communities between unmanaged forests and commercial forests in a mountainous environment （Pyrenees France）. The aim was to evaluate the impact of forestry activities on moth diversity. The data collected from the insects were analysed with a Bayesian specific similarity index （noted SSP index） and by statistical biodiversity indexes comparison. It was seen that diversity and richness were decreased in the plantation compared to the unmanaged forest. Interestingly, the composition of the communities of moths was shown to be not only related to the presence/absence of host plants, but also to be in relation with changes in the differences in forest architecture （i.e. the relative coverage by the different vegetation levels）. However, the moth community in the commercial forest still has a high capacity to converge with the moth community present in more natural forests. We report here a list of 177 species of moths, providing information on the distribution of some uncommon species, poorly studied as yet in the Pyrenees.

关键词： biodiversity Lepidoptera Heterocera mountainous forest ecosystems

Acceptability of Immunization against COVID-19 by the Populations of the Kasenga State Health Area in the Uvira Health Zone, DR Congo

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Journal of Immune Based Therapies, Vaccines and Antimicrobials 2024年第3期13卷 33-46页

作者： Derrick Bushobole Akiba Eric Amuri Madabali Robert Bushambale Fataki Abel Asende Luhendama jacques Mutono Matongo Faustin Bukuru Mudage Christian Banyakwa Mitunda Saili Stay Mushobekwa Michel Byaombe Wa Ngene Martin Longolongo Kiza Paulin Mulogoto Rushanika Emmanuel Nirambo Rujanjika Henry Manya Mboni Criss Koba Mjumbe Department of Public Health Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Department of Laboratory Techniques Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Nursing Science Sector Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Department of Public Health University of Lubumbashi Lubumbashi DR Congo Department of Pharmaceutical Techniques University of Lubumbashi DR Congo Department of Pharmaceutical Techniques Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo

Introduction: COVID-19 was an emerging disease putting all public health systems in countries around the world in a state of emergency. To be able to prevent its spread and morbidity and mortality, several appropriate strategies were necessary, such as vaccination. The latter has been the subject of controversy. The objective of the present study is therefore to evaluate the factors associated with the acceptance of this vaccine within the population of the Kasenga State Health Area. A result which will shed light on future strategies to be put in place for possible new vaccines. Methodology: Is a prospective and analytical cross-sectional study conducted over a period of approximately 1 month from January 5 to February 5, 2024. A survey questionnaire in Kobotoolbox was useful for collecting data. STATA software was very important for us in analyzing the data collected. Results: Prevalence of vaccination against COVID-19 among the population of the Kasenga State Health Area is 37.5% (28.4 - 45.6). The study revealed that reluctance is observed among most of the population for different reasons, including, first and foremost, the deliberate aspect of not wanting to take the vaccine (46.6%) and rumors that this antigen is dangerous and harmful (32.9%). 72.5% of respondents believe that the COVID-19 vaccine is a fabrication, unhealthy and that the disease itself never existed. The study proved that there was a statistical relationship between age (p = 0.001) and adherence to vaccination. And the refusal of respondents to recommend the vaccine to loved ones was a factor associated with non-adherence to vaccination (OR = 7.901, 95% IC [3.028 - 20.615], p = 0.000). Conclusion: Vaccination against COVID-19 was not well accepted by the population of the study site. Raising public awareness and involving community leaders and political-administrative authorities, which has not been done well, would play an important role in the good perception of the disease, of the vaccine

关键词： COVID-19 Vaccination Kasenga State Health Area Associated Factors Uvira Health Zone City of Uvira