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The Chinese immigrants in Germany have a special story to tell. Due to the political turbulence in both China and Germany in the second half of the 20th century, migration from China to Germany did not fully take off until the reunification of Germany in 1990. The current community of Chinese immigrants in Germany has a short history, compared to those in the US and Southeast Asia. Chinese immigrant families mainly consist of the first and the second generations, with a high percentage of university graduates and young professionals who arrived in Germany with a student visa. This dissertation is an ethnographic study of Chinese immigrants in Berlin, focusing on the process of how the second generation loses and learns the Chinese language within the resources of the nuclear families, but without a sizable ethnic Chinese community. This thesis mainly draws on and contributes to the scholarship in migration studies and language socialization. I conducted a 12-months fieldwork in the classrooms of one public primary school and several private Chinese language schools, the Sunday programs for children at Chinese Christian churches, and numerous Chinese immigrant households throughout the city of Berlin. Driven by the anxieties of acquiring decent education, wider career opportunities, upward mobility and eventually political power, the first-generation Chinese immigrants often focus on the fabrication of a German identity for their children, and put their Chinese origins aside. However, the loss of the Chinese language among the second generation can lead to the lack of communication between parents and children, as well as the increase of inter-generational conflicts. Especially for immigrant families with no other family member in Germany and with limited transnational connection to China, institutions like language schools and Christian churches in Berlin become important venues, not only for the second generation to obtain additional education, but also for the first generation to gain further resources and authorities for themselves to amend the challenges at home. Based on extensive ethnographic materials, this thesis examines the interactions between the two generations of Chinese immigrant families in Berlin, and analyzes their ambivalent relation towards the Chinese language and their Chinese background. Following the literature on language socialization and its emphasis on children’s agency, I investigate the scope and the content of this agency, and address the impact of parents on the formation of children’s agency in learning their heritage language. Building on Bourdieu’s concepts of “a relation to a language”, “implicit” and “explicit socialization”, I argue that parents’ relation to their Chinese background constitutes considerably children’s relation to the Chinese language, and children’s acknowledgement of their Chinese background.

In view of the high content of the highly stable anthocyanin in red radish roots, the plant is considered as a potent source of natural anthocyanins. However, the presence of off flavor in their anthocyanin extracts is the only limitation as far as their application in food and pharmaceutical industries is concerned. The aim of this work was to develop a suitable method for extracting the off flavor free red radish root anthocyanin, while conserving high anthocyanin yield. Results showed that phosphoric and citric acidified hexane (pH 2.5) extracts yielded maximum anthocyanin levels of 208.37 mg/100 g and 202.89 mg/100 g fresh radish, respectively with lower percentage polymeric color and higher color density, chroma and hue angle compared to other extracts at different pH values. Tentative anthocyanin identification by UPLC-TQ-MS showed 12 glycosylated anthocyanins substituted at C3 and C5 in phosphoric acidified extracts and only 10 in citric acidified extracts. In addition, analysis of total glucosinolates (GSLs) revealed significant inhibition of glucosinolate degradation in acidified hexane extracts (pH 2.5) compared to the other extracts. The off flavor evaluated by GC-MS revealed a significant decrease of isothiocyanates, sulfides and nitrogen containing compounds in acidified hexane (pH 2.5) compared to other extracts. Furthermore, dehydration and rehydration of extracts showed that over 70% of off flavor compounds could be removed in two phases (aqueous and hexane) during hexane removal. Results of sensory evaluation confirmed that the red radish root anthocyanin from the phosphoric acidified hexane (pH 2.5) was closer to the color and odor characteristics of the commercial red radish anthocyanin. Therefore, the phosphoric acidified hexane method could be a suitable method to extract off flavor free anthocyanin from red radish roots.

The phase constitution, microstructures and microwave dielectric properties of CaxZn1−xZr0.8Sn0.2Nb2O8 (x = 0.00, 0.05, 0.10, 0.15) ceramics prepared via a solid-state reaction method were reported for the first time. The X-ray diffraction patterns of CaxZn1−xZr0.8Sn0.2Nb2O8 ceramics showed the monoclinic structure of ZnZrNb2O8 and the second phase columbite CaNb2O6 were obtained. The microwave dielectric properties of the CaxZn1−xZr0.8Sn0.2Nb2O8 ceramics were strongly affected by the change of crystal structure and the content of second phase. With the increasing Ca2+ content, the dielectric constant (e r ) and the Qf value decreased and the temperature coefficient of resonant frequency (τ f ) moved to the positive direction. The typical values of e r = 26.64, Qf = 61,350 GHz, τ f = −21.43 × 10−6/°C were obtained for CaxZn1−xZr0.8Sn0.2Nb2O8 (x = 0.15) specimens sintered at 1275 °C for 6 h.

High performance X8R BaTiO3-based ceramics with pure perovskite phase were prepared by nanocomposite doping method. The phase structure, dielectric and electrical properties and the “relaxorlike” characteristic of ceramic materials are systemically studied. According to XRD and TEM analysis, the nanocomposite dopants via sol–gel method are uniform and well dispersive. The role of NiNb2O6 on dielectric properties and phase structure of BaTiO3-based ceramics is investigated. The properties comparison of samples prepared by nano-doping and conventional process is accomplished. SEM micrographs reveal that the grain size of BaTiO3-based samples is more uniform by nano-doping process. Meanwhile, bulk densities and dielectric properties are enhanced. The 1.5 wt% NiNb2O6-doped sample sintered at 1280 °C shows the optimal dielectric performance (ɛr = 4160, tanδ

The (Zn1−xCox)ZrNb2O8 (x = 0.1, 0.2, 0.3, 0.4) ceramics were synthesized by the conventional solid-state reaction route and sintered in the temperature range of 1160–1320 °C. The microstructure and microwave dielectric properties were investigated systematically. The X-ray diffraction results showed that the (Zn1−xCox)ZrNb2O8 ceramics exhibited a single monoclinic structure. The variation trend of dielectric constant (e r ) was in accordance with variation trend of relative density. The Qf value decreased with the decrease of the packing fraction. The temperature coefficient of resonant frequency (τ f ) moved towards positive due to the increase of B-site bond valence. In conclusion, the excellent microwave dielectric properties were obtained for Zn0.9Co0.1ZrNb2O8 ceramics sintered at 1240 °C for 4 h: e r = 27.93, Q × f = 68,615 GHz (where f = 6.95 GHz), and τ f = −61.94 × 10−6/°C.

A novel system of lead-free X8R BaTiO 3 -based dielectric materials with high dielectric constants was prepared via conventional mixing method. The phase structure, dielectric and electrical properties and the “relaxorlike” characteristic of ceramic materials were systemically studied. The XRD results indicate that no secondary phase formed in the CaZrO 3 -doped samples after sintering. SEM micrographs reveal that the grain size of CaZrO 3 -doped BaTiO 3 -based samples are not uniform, ranging from 0.2 to 0.9 µm. Bulk densities and dielectric properties were measured as a function of CaZrO 3 concentration. The Curie temperatures of all CaZrO 3 doped samples increase due to the existence of an internal stress between grain cores and shells caused by the diffusion of CaZrO 3 . The oxygen vacancies have a profound effect on the dielectric loss and frequency characteristics. The 3.5 wt% CaZrO 3 -doped sample sintered at 1250 °C showed the optimal dielectric performance ( e r =4330, tan δ C / C 20 °C ≤±14%) that satisfied EIA-X8R specification.

An ultra-broad temperature stable (−55 to 300 °C, ΔC/C20 °C