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111.
112.
Watching the profound changes in the last decades in virtually any big city in Western Europe in the field of migration, minority and ethnicity, many national and urban governments in Europe fear for large spatial concentrations of immigrants who originate from non-industrialised countries. The basic assumption behind that attitude seems to be that large concentrations of (ethnic) immigrants would prevent their full integration and thus participation in society. Such a risk of insufficient integration would particularly be great when the immigrant population occupies the lower positions of the socio-economic ladder. However, two things should be investigated with care. First, what are the actual explanations for the social and spatial divisions that are encountered in cities? What does that imply for the (spatial) inequality in Dutch cities? Second, what can be said about the effects of recent changes that can be observed with respect to the explanatory dimensions in the Dutch context? How do these compare to the actual size and stability over recent years of the spatial patterns of immigrants? Popular images of the processes of immigration describe the development of 'ethnic ghettos'. These would particularly develop where state intervention in the spheres of housing and in many other spheres is small or, as in the Netherlands, is declining. This paper investigates whether that view does justice to the actual development, applying micro-level data on immigrant settlement patterns in the city of Amsterdam over the period 1994-99. It is argued that ethnic residential concentrations tend not to be stable and are just growing areal units, but many changes can be shown, which may reflect processes of housing careers and of integration in society. 相似文献
113.
Yoshiaki Kitamura Satoko Sako Azusa Tsutsui Yasunari Monguchi Tomohiro Maegawa Yukio Kitade Hironao Sajiki 《Advanced Synthesis \u0026amp; Catalysis》2010,352(4):718-730
A ligand‐free and heterogeneous palladium on carbon (Pd/C)‐catalyzed hetero‐Suzuki–Miyaura coupling reaction has been developed. The protocol enables the construction of both heterocyclic‐alicyclic and heterocyclic‐heterocyclic biaryl derivatives in good to excellent yields. Furthermore, Pd/C could be reused. The time‐course study clarified that palladium was leached into the reaction media as the reaction proceeded and then completely deposited on the carbon support. 相似文献