Search results for "FT"
showing 10 items of 16187 documents
La métallurgie du fer au Sahel : Répartition spatiale de bas fourneaux au Sud-Ouest du Niger. Premiers résultats
2010
International audience; A 15 km à l'Est de Niamey (Sud-Ouest du Niger), une prospection pédestre exhaustive a permis de dénombrer plus de 4000 bas-fourneaux sur un bassin versant de 24 km². Ils sont identifiables par la présence de scories correspondant aux résidus de réduction du fer. Ce grand nombre de structures de réduction est lié au fonctionnement à usage unique des bas-fourneaux, qui est peu étudié dans la région ouest africaine. Les premières études de répartition spatiale montrent que l'implantation de ces bas-fourneaux est principalement soumise à la géomorphologie. Les forgerons ont installé leurs sites de réduction à proximité des talus de plateaux où affleure le minerai de fer …
Structure and determinants of production in Textile-Clothing-Leather-Skins (TCLS) craft industry in Benin: a study based on investigations of the val…
2014
Lieu et date de la conférence modifiées. Prétoria 31Juillet au 2 Août 2014 (Au lieu de Kigali -Rwanda); International audience; Sustainable economic growth in Benin requires a better understand of the informalsector, which contributes to two-thirds of GDP. Particularly, craft industry and TCLSsubsector is one of informal activity sector to be handled. The objectives of this work wereto identify the structure and factors that determine the production in TCLS craft industry.This study was based on a survey carried out in February 2011 on value creationdata in craft industry of TCLS in Benin. Lack of data induced by informal activities wascircumvented using an imputation method. A Multiple Cor…
Characterization of Chlorolignins in Bleached Kraft Pulp Mill Effluents Using Elemental Analysis and Fingerprinting by CuO Oxidation And Hplc
1994
Abstract Elemental analyses and chemical degradation techniques were applied to characterize lignin compounds in different stages of the chlorine bleaching process and in total mill effluent. Ultrafiltration was used for separation of chlorolignins into three nominal molecular weight fractions. Alkaline CuO oxidation products were analyzed by HPLC with diode array detection. Major compounds were identified by reference to authentic compounds. For comparison, native lignins (MWL), kraft lignins, and humic substances were studied as well. The oxygen, carbon and organic chlorine contents were closely similar in the various mill samples and their fractions. In all mill samples, vanillin and 6-c…
Numerical analysis of masonry structures via interface models
2001
The present paper is devoted to the theoretical formulation and numerical implementation of an interface model suitable to simulate the behavior of mortar joints in masonry structures. The interface laws are formulated in the framework of elasto-plasticity for non-standard materials in order to simulate the softening response which occurs along the decohesion process in presence of shear and tension tractions. A variable material dilatancy parameter is introduced together with a further geometrical dilatancy related to the roughness of contact surfaces after joint fracture. An asperity model is adopted with the aim to describe the evolution of the contact surface shape during the loss of co…
NMR Spectroscopic and quantum chemical characterization of the (E)- and (Z)- isomers of the penta-1,3-dienyl-2-cation
2003
Dilute solutions of the (E )− and (Z )− isomers of pent-1,3-dienyl-2-cations (1) were obtained from reaction of 4-chloro-1,2-pentadiene (2) with SbF5 in SO2ClF/SO2F2 at −135 °C using high-vacuum co-condensation techniques. The experimental NMR spectra of the mixture of the two isomers were compared with quantum chemical 13C NMR chemical shift calculations at HF-SCF, MP2, CCSD and CCSD(T) levels using MP2/tzp geometries. Quantum chemical shift calculations were performed with a tzp basis (9s5p1d/5s3p1d) for carbon and a dz basis (4s/2s) for hydrogen using gauge-including atomic orbitals (GIAOs). The HF-SCF calculations deviate significantly for the positively charged carbon atoms of the ally…
Estimating the substitutability between private and public consumption: the case of Spain, 1960–2003
2005
This paper examines the relationship between private and public consumption using Spanish data over the period 1960–2003, using a two-good permanent-income model. We extend previous analysis addressing the question of whether this relationship is stable over time, or exhibits a structural break allowing the instability to occur at an unknown point in time. Our empirical results indicated the existence of a long-run relationship between private and public consumption. We also detect a structural change of regime shift in the cointegration regression around the time of 1973–74. Finally, the estimated intratemporal and intertemporal elasticities of substitution between the two types of expendi…
Development of core-shell colloids to study self-diffusion in highly concentrated dispersions
2007
To study single particle motion in highly concentrated colloidal dispersions, a host-tracer colloid system was developed, consisting of crosslinked polymer micronetwork spheres placed in a good solvent. The host colloid is made invisible to the experimental probe by matching its refractive index to that of the solvent. For the tracer particles a core-shell structure was chosen to ensure the interaction potential to be identical to that of the host particles. Therefore the shell was made of the same polymer as the host. The core differs in refractive index from the solvent and is therefore visible due to scattered light.
Allogeneic Stem Cell Transplantation for Acquired Aplastic Anemia: Better Outcome with Bone Marrow as Compared to Peripheral Blood in HLA-Matched Sib…
2009
Abstract Abstract 876 Background: Transplantation of bone marrow (BM) from a HLA-matched sibling donor is an effective treatment for severe aplastic anemia (AA) with long-term survival in excess of 80%. In the recent years there were two trends in allogeneic stem cell transplantation (SCT) for AA: (1) increasing proportion of transplants performed from matched unrelated donors (MUD) and (2) increasing proportion of transplants using peripheral blood progenitor cells (PBSC) as stem cell source instead of BM. A similar switch to PBSC over BM grafts is reported in leukemia transplants. PBSC grafts for leukemia are associated with higher rates of chronic graft-versus-host disease (cGVHD). This …
A Look at Valencia’s Elections of the 28th of April and the 26th of May 2019
2020
This paper analyses the main features of the Valencian media coverage of the elections held in Spain in the Spring of 2019 (General, Regional, Municipal, and European elections). We shine a spotlight on the key themes covered by the main newspapers, radio and TV stations, and on the campaign strategies parties used to define ideological blocs on the left and right.
Tuning four-wave mixing through temperature in ethanol-filled photonic crystal fiber
2016
In this paper, continuous tuning of four-wave mixing bands in an ethanol-filled photonic crystal fiber is investigated. A wide tuning range of the parametric bands, from 745 nm to 920 nm (signal) and from 1260 nm to 1710 nm (idler), is achieved through the thermo-optic effect. This corresponds to a frequency tuning range higher than 2000 cm−1; such wide range can be particularly useful in applications that require broadband wavelength conversion, e.g., CARS microscopy. Numerical calculations are in good agreement with experimental measurements.