2,637 research outputs found
Dilead(II) chromium(III) heptaÂfluoride
Single crystals of the title compound, Pb2CrF7, were obtained by solid-state reaction. The monoclinic structure is isotypic with Pb2RhF7 and is built up of CrF6
3â octaÂhedra isolated from each other, inserted in a fluorite-related matrix of PbF6 distorted octaÂhedra, and PbF8 square antiÂprisms sharing edges and corners. The seventh F atom is âindependentâ, connected only to three Pb atoms within FPb3 triangles, sharing an edge and building an almost planar Pb4F2 unit, so that the formula can alternatively be written as Pb2F(CrF6)
Les relations halieutiques internationales du Mexique
With the extension of the Exclusive Economic Zone, Mexico has been endowed with a tremendous oceanic potential. Although without any maritime history, the country embarked on the development of its marine biological resources ; an ailing ' 'agricultural revolution" was replaced by the , "blue revolution". An ambitious national plan for the development of its fisheries was set up; its implementation would improve the food supply situation, create thousands of jobs, increase exportations and, by turning out foreign fleets from its territorial waters, would also flatter Mexican nationalism. However, only part of these ambitions came to be. Lack of maritime know-how and a weak internal market have prevented Mexico from becoming free from external constraints. Although it has become an important producing country, yet it still remains dependent on the international market
7,9-Bis(hyÂdroxyÂmethÂyl)-7H-purine-2,6,8(1H,3H,9H)trione
The structure of the title uric acid derivative, C7H8N4O5, from human kidney stones, is characterized by the C and O atoms of one of the two hyÂdroxyÂmethyl groups being disordered nearly equally over three different sites. In the crystal, molÂecules are connected by a three-dimensional hydrogen-bonding scheme though they look stacked in planes nearly parallel to (04)
Caroline Grillot, VolĂ©es, envolĂ©es, convolĂ©es⊠Vendues, en fuite, ou re-socialisĂ©es: les âfiancĂ©esâ vietnamiennes en Chine (Abducted, Flown, Married⊠Sold, escaped or rehabilitated: Vietnamese fiancĂ©s in China),
Traditions of exogamy and patrilocality of marriage in Asia have long led women to leave their villages, regions, or even countries in search of a husband. Distances have tended to grow, at first within frontiers and then beyond. Inside China, many works have shown a correspondence between migrations for marriage and spatial hierarchy linked to development: using mobility through marriage, women have sought to move to more affluent coastal regions. Chinese womenâs migration for marriage has c..
Les travailleuses du sexe chinoises entre répression et revendication
Dans les débats autour de la pénalisation des clients de la prostitution ces trois derniÚres années, les travailleuses du sexe chinoises ont joué un rÎle de premier plan. HélÚne Le Bail revient sur leur parcours, leur action et les violences dont elles sont la cible
The Migration of Experts and Savoir-faire
This article focuses on the practice of French cuisine in Shanghai and questions the permanence of this professional niche. It combines an anthropological approach to culinary techniques with a sociological approach to workforce migration, tracing the ways in which the discourse and practices of chefs and maĂźtres dâhĂŽtel working in French cuisineâs restaurants employ forms of ethnocultural and technical legitimacy. The case of Shanghai, a city undergoing rapid transformation in its modes of consumption, provides a clear illustration of the shifts that have occurred over the last ten years in the hierarchy of Western migrants and Chinese locals: the symbolic and material privileges offered to the former are beginning to disappear, and professional recognition is increasingly becoming based on savoir-faire and a strong work ethic
ICE SLURRY PRODUCTION IN A TUBULAR HEAT EXCHANGER
International audienceOne of the challenges of ice slurry generation using a heat exchanger is to overcome the risk of choking. The nucleation usually appears after a supercooling state that remains a key aspect of this technology. In order to focus on this crucial problem, the crystallization of a water ethanol solution was studied in a transparent tubular heat exchanger. Our experiments consisted in cooling the solution until ice slurry formation. Flow visualization permitted mainly to determine the conditions of crystallization according to the flow rate. A limited range of flow rate permitted to obtain the desired ice slurry quality. The heterogeneous crystallization appeared on the wall and dendrites began to develop before being carried away by the solution. Experiments also indicated that dendrites growth from the freezing front upstream in the counter flow direction. The velocity of this retro-propagation phenomenon was estimated using an image analysis tool. Temperature measurements also provided important information on this retro-propagation. Selected process parameters have to be properly adjusted (flow rate, wall properties âŠ). This technology has been patented by the CNRS in selected European countries and in the USA
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