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351.
Christine Barwick 《Urban geography》2018,39(6):916-934
Creating social mix in neighborhoods has been an important urban policy during the past years. The aim is the development of category-crossing ties between the middle and lower classes. However, studies found little evidence of such ties. This paper identifies two reasons why this might be the case. First, studies usually analyze the resource flow from native middle classes to disadvantaged residents. Second, the resource flow is analyzed within one neighborhood only. Based on interviews and network analysis with second generation, upwardly mobile Turkish-Germans in Berlin, I show that they act as cultural and language brokers, benefiting lower class co-ethnics. They provide exactly the information and resources to people with a lower class background that are envisioned by social mixing programs. Moreover, the resource flow occurs within but also across neighborhoods, whereby ‘second neighborhoods’ such as the previous neighborhood or the neighborhood where the workplace is located are particularly important. 相似文献
352.
353.
Rates of splash detachment from a sandy soil of the Cottenham Series, subjected to a five-minute design storm of 50 mm/h with a kinetic energy of 127 J/m2 and a median volume drop size of 3·2 mm supplied from a rotating-disc rainfall simulator, are determined without a plant cover and with the cover of a single Brussels sprouts plant. Measurements are made at regular intervals throughout the growing season. Plant canopies of 10 to 25 per cent result in reductions of 10 to 25 per cent in rainfall volume and 10 to 81 per cent in rainfall energy. The volume and energy of the rain beneath the plant are significantly (P < 0·05) correlated with its number of leaves (r = ?0·84 and ?0·92 respectively for n = 49). No reduction was observed in the rate of splash detachment which averages 1·2 kg/m2 for the design storm with and without the plant. The detachment rate was found rather surprisingly to be inversely related to the energy of the rainfall under the plant and positively related to the number of leaves. As the number of leaves increases, so does the detachment rate per unit of rainfall energy. 相似文献
354.
Vincent Renard Kazuaki Nakamura Jacques Angelier Jacques Azema Jacques Bourgois Christine Deplus Kantaro Fujioka Yozo Hamano Philippe Huchon Hajimu Kinoshita Pierre Labaume Yujiro Ogawa Tetsuzo Seno Akira Takeuchi Manabu Tanahashi Akinori Uchiyama Jean-Louis Vigneresse 《Earth and Planetary Science Letters》1987,83(1-4)
Leg 2 of the French-Japanese 1984 Kaiko cruise has surveyed the trench triple junction off central Japan, where the Japan, Izu-Bonin and Sagami Trenches intersect. The Izu-Bonin Trench is deeper than the Japan Trench and filled by a thick turbiditic series. Its anomalous depth is explained by the westward retreat of the edge of the northwestward moving Philippine Sea plate. On the contrary to what happens in the Japan Trench, horst and graben structures of the Pacific plate obliquely enters the Izu-Bonin Trench, suggesting that the actual boundary between these two trenches is located to the north of the triple junction. The inner wall of the Izu-Bonin Trench is characterized in the triple junction area by a series of slope basins whose occurrence is related to the dynamics of this area. The northernmost basin is overthrust by the edge of the fore-arc area of the Northeast Japan plate. The plate boundary is hardly discernible further east, which makes it impossible to locate precisely the triple junction itself. These features suggest that large intra-plate deformation occurs there due to the interaction of the plates involved in the triple junction and the weak mechanical strength of the wedge-shaped margin of the overriding plates. 相似文献
355.
Seasonal variations in total particle concentrations at five remote Southern Hemisphere sites in Samoa, Tasmania and Antarctica are compared. The dominant particle production mechanism is deduced to be photochemical, with concentrations dictated by the availability of radiation in the eight months centred on the winter solstice. There is little variation with latitude in the mean summer concentrations. The middle troposphere is shown to act as an important reservoir of photochemically-produced particles in Tasmania and probably in the Antarctic. It is suggested that primary-particle production is mainly through the oxidation of dimethyl sulphide and that these particles then act as centres of condensation for sulphuric acid formed by the oxidation of sulphur dioxide. 相似文献
356.
The Cenozoic lacustrine basin of Anloua (Adamaoua, Cameroon), is filled with the weathering products of the surrounding rocks. In order to determine the origin of these sediments, multi-element, especially trace element, analysis of their < 2 μm fraction was undertaken. The chemical compositions of these fractions were compared with those of the rocks surrounding the basin by multivariate statistical analysis and also graphically. A principal component analysis allowed the most discriminant elements to be selected, and a hierarchical ascending classification (HAC) made with these elements divided the samples into groups. Some of these groups contain < 2 μm fractions of both the lake sediments and surrounding rocks. These sediments are determined as deriving by weathering from the surrounding rocks. Some of the other groups contain no samples from the surrounding rocks and their petrographic origin cannot be given. A graphic comparison of the relative amounts of the elements (determined by HAC) from the < 2 μm fractions of the various groups and the rocks surrounding the basin allowed attribution of a petrographic origin for the various sediments analysed by using the fit between the curves.
The clay mineralogy, the amounts of Ti, Zr, and heavy minerals in the < 2 μm fractions and their distribution in the area studied, as well as the presence of angular quartzite pebbles in some sediments gives an indication of the paleogeography of the Anloua basin. There was deltaic input towards the north and a high energy input, possibly torrential, to the west. 相似文献
357.
Mainstream,Inclusionary, and Convivial Places: Locating Encounters Between People with and Without Intellectual Disabilities 下载免费PDF全文
Convivial encounters, where strangers experience temporary shared identification with each other, are valorised in recent literature for their transformative potential. For people with intellectual disabilities, encounters with strangers are an important aspect of social inclusion, and opportunities to become recognised and known within their communities. This paper considers the question of what places are most conducive for convivial encounters between people with and without disabilities. The paper draws on findings from a study conducted in the State of Victoria, Australia, that involved ethnographic observations of encounters between people with and without intellectual disabilities, as well as a survey and face‐to‐face interviews with people with intellectual disabilities, their support workers and neighbours. The discussion is framed around two broad categories of place, mainstream and specialist, which have the potential to be inclusive and convivial. 相似文献
358.
Christine Malfoy Claude Fontaine Anne Pantet Philippe Monnet 《Comptes Rendus Geoscience》2007,339(16):960-969
The rheological study of colloidal suspensions contributes to the understanding of the aggregation phenomena of colloidal particles within a suspended fluid. The infra-2-μm (equivalent diameter) fraction of a bulk material, Volclay MX-80 bentonite was intensively analysed in order to understand the relative rheological data scattering observed with Li-smectite suspensions, prepared with the usual saturation procedure. A good mineralogical characterisation, especially for secondary minerals, coupled to a verification of cation exchanges on clayey fraction allowed us to propose a new way for investigating the observed differences of the bentonites rheological behaviour. Indeed, for a well Li-saturated smectite obtained from the purified infra-2-μm fraction, rheological data proved to be very accurate and perfectly reproducible. This emphasises the role of other minerals as well as the commonly observed discrepancy between the rheological behaviours of natural and industrial bentonites. 相似文献
359.
Jochen Schaumburg Christine Schranz Gabriele Hofmann Doris Stelzer Susanne Schneider Ursula Schmedtje 《Limnologica》2004,34(4):302-314
A new assessment system for macrophytes and phytobenthos in German lakes according to the Water Framework Directive of the European Community is described. Based on biological, chemical and hydromorphological data from about 100 lake sites covering the main ecoregions, hydromorphological lake types and degradation forms, biocoenotic types could be defined. For developing a classification system the quality element macrophytes and phytobenthos was divided into two components: macrophytes and benthic diatoms. For macrophytes 4 and for benthic diatoms 4 lake types were identified. The benthic vegetation at reference conditions is described and degradation is characterised as deviation in benthic vegetation species composition and abundance from the reference biocoenosis. For classification in five ecological status classes, several metrics were developed and used in combination with existing indices. For a few of the described lake types further investigations are necessary before a classification can be developed. 相似文献
360.
Terrigenous sedimentation processes along the continental margin off NW Africa: implications from grain-size analysis of seabed sediments 总被引:2,自引:0,他引:2
The terrigenous fraction of seabed sediments recovered along the north‐west African continental margin illustrates spatial variability in grain size attributed to different transport mechanisms. Three subpopulations are determined from the grain‐size analyses (n = 78) of the carbonate‐free silt fraction applying an end‐member modelling algorithm (G. J. Weltje, 1997). The two coarsest end‐members are interpreted as representing aeolian dust, and the fine‐grained end‐member is related to fluvial supply. The end‐member model thus allows aeolian fallout to be distinguished from fluvial‐sourced mud in this area. The relative contributions of the end‐members show distinct regional variations that can be related to different transport processes and pathways. Understanding present‐day sediment dispersal and mixing is important for a better understanding of older sedimentary records and palaeoclimate reconstructions in the region. 相似文献