Sintering,microwave properties,and circulator applications of textured Sc-substituted M-type ferrite thick films

Sc³⁺ substituted M-type ferrites are effective microwave magnetic materials with a ferromagnetic resonance frequency in the range of 20 GHz–50 GHz. We report on the fabrication of oriented ferrite thick films as microwave components for application in the K_a-band at 30 GHz. Films of BaFe_11.5.Sc_0.5O₁₉ were prepared by screen-printing on alumina substrates, drying in an external magnetic field, and sintering at 900 °C. Low-temperature sintering is achieved through use of a mixed BBSZ/CuO sintering aid. A strong anisotropy of the sintered ferrite films is revealed by XRD analysis. Microwave properties of the films were determined in a coplanar waveguide setup. The ferromagnetic resonance frequency of the films is at 30 GHz and the textured films possess good nonreciprocal properties which scale with film thickness. The films were tested in a Y-junction circulator, and represent promising materials for self-biased microwave components fabricated in thick film technology.     

Electric transport properties of rare earth doped YbxCa1-xMnO3 ceramics (part I: Optimization of ceramic processing)

A comprehensive study was performed in order to find the effect of different calcination and sintering conditions on the physical properties of calcium manganite ceramics in dependence of temperature T and partial pressure of oxygen p(O₂). The eventual formation of oxygen vacancies during sintering was investigated and the results were confirmed by monitoring the release of oxygen using a ZrO₂ oxygen sensor. The phase transition behavior was studied using thermogravimetric analysis (TGA) in a wide range of p(O₂) ≈ 10^?1 MPa down to 10^-19 MPa at high temperatures accompanied by dilatometry- and XRD-measurements. Furthermore, the present study reveals for the first time a way for reducing and preventing crack formation that may occur during sintering. The present systematic research provides essential fundamental information before performing electrical measurements necessary in order to understand important factors about charge carriers and electrical transport mechanism.     

Showcase and window to the world: East German architecture abroad 1949–1990

For decades, German Democratic Republic (GDR) architecture was seen as parochial and dictated by the Soviets, yet increasing scholarly interest has generated a picture of debates and specific practices that were embedded in the global process of expansion and crisis of Modernism. Meanwhile, and influenced by the East-West conflict, competing concepts of modernization and national identity arose in the so-called Third World, initiating multifarious cultural transfer processes. This article analyses to what extent the architects from the GDR – a country whose building practice was increasingly shaped by the principles of industrial prefabrication – have played a part in regional contexts and construction methods. It also asks what their role was in international organizations such as Union Internationale des Architects and UNESCO, which promoted their practical engagement abroad. The subject raises issues of possible freedom of action in creative design and fusion processes, but also of bureaucratic constrictions and international relationships ending in unexpected conflicts. The examples outline the field of activities that stretches from pure blueprint delivery for a memorial competition to long-standing work on location when planning whole neighbourhoods. Furthermore, the article examines how the challenges of international planning impacted building culture within the GDR itself.     

台州市"白云阁"景观建筑设计

本文系统地介绍了浙江台州白云阁的设计过程,并着重分析建筑的生成过程,尝试从不同角度探求符合当代社会特质的现代景观建筑之路。台州市“白云阁”景观建筑设计是一次有意义的探索。     

相会"建筑师之家"--记德国杜塞尔多夫"中国当代建筑展"

“中国当代建筑展”于今年10月10日至12月20日在德国莱茵河畔著名城市杜塞尔多夫市“建筑之家”举行,此次展览在德国产生了较强烈的反响,获得了圆满成功。近二十家中国大型设计院和中小型建筑事务所参加了此次展览。这次展览是由“德中建筑协会-DCB”及德国最大的北威州建筑师协会AKNW联合举办的。     

福建省体育馆工程施工技术研究

福建省体育馆工程是建设部重点实施技术示范工程,在施工中结合工程施工特点和创优目标,研究、开发、应用了四大类共10余项重点实施新技术,完成了推新任务和创优的目标。     

德国建造规划的技术框架

本文基于建造规划的课题研究,以建造规划中的重要符号——建造窗口为核心,系统总结了建造规划的技术框架,并进而详细剖析了其主要技术特点。     

2005爱知世博会租赁式展馆建筑设计研究

2005爱知世博会各参展国均采用租赁式展馆.其设计关键为,不论在室内外空间上还是在建筑立面处理上,均需避免单调乏味之感.此届世博会租赁式展馆的设计手法为:各国依据展览的需要,确定自己租用标准模块的数量及组合方式.紧密结合自然地形,将各国展馆进行各种形式的组团整合,构建出丰富多彩的外部空间.在建筑形象设计上,充分体现设计主题及巧妙地体型处理,同时运用建筑材料选用及色彩搭配等手法,使简单的形体表现出形态迥异的外观效果,创造出极具个性的建筑风格.这种租赁式展馆的广泛使用可能会成为未来世博会部分建筑设计的一种发展趋势.     

德国国家空间规划的最新进展解析与启示

空间规划是国家政府宏观调控空间发展的重要手段之一。以概述德国空间规划为基础,重点从制定背景、主要内容、发展特征及其未来图景等方面,对2000年以来德国国家空间规划进行解读分析,并提出对我国相关空间规划的有益启示。     

重檐八方亭作法实例（二）——中山公园览粹亭

重檐八方亭作法以中山公园览粹亭为实例。本文介绍重檐八方亭的丈尺作法、大木装修作法，瓦作、石作、油漆彩画作的规格尺寸、用料和做法，以及该项目的全部图纸。