Carbopol 934树脂作为清洗材料的应用研究

在对文物进行保护处理过程中,清洗是非常重要工作之一。新的清洗材料、清洗工艺的研究,对文物保护技术的发展具有重要价值。本研究对Carbopol 934树脂应用于纺织品清洗的清洗效果、清洗工艺进行了研究,并对其在纸张和砖石文物上应用的可能性进行了尝试。研究结果表明,Carbopol 934树脂应用在纺织品清洗中具有作用时间长、扩散小的优点;同时应用隔离层能减少残留,达到更好的清洗效果;可有效地用于砖石、纸张和织物上污垢的去除。     

中国国家博物馆环境空气质量监测报告

为加强博物馆藏品的预防性保护,需全面掌握博物馆馆舍内外空气质量的现状,对其进行评估,进而采取有效措施治理改善,妥善保护人类文化遗产。本馆采用美国普滤(Purafil)公司研发并提供的检测技术,在馆舍内外选定八个测试点进行了腐蚀试片测试。根据监测数据得知,本馆处于高浓度极具腐蚀性的二氧化硫气态物质的包围中,已造成对金属、纸张等文物的危害,治理改善收藏环境迫在眉睫。创造保存各类藏品的微环境空间,是治理改善博物馆收藏环境的有效手段。     

Foreign Policy Reviews and Canada's Trade Policy: 1968–2009

Governments, upon assuming office, most often seek to refocus foreign policy according to the preferences of the new prime minister and the primary means of accomplishing this has been to release a white paper outlining the priorities of the new government. This article will demonstrate that discussions of trade issues reinforce existing studies questioning the innovation and impact of white papers. The purpose of this analysis, however, is not to dwell on the utility of white papers and foreign policy reviews but instead search for a deeper understanding of why trade policy is discussed in an unoriginal and superficial manner. The focus of the article is on the period from 1968 to the present.     

Optimum Design of Passive Control Devices for Reducing the Seismic Response of Twin-Tower-Connected Structures

Based on the 3-single-degree-of-freedom (SDOF) model of twin-tower structures linked by the sky-bridge and passive control devices, the frequency functions and the vibration energy expressions of the structures are derived by using the stationary white noise as the seismic excitation. The analytical formulas for determining the connecting optimum parameters of viscoelastic damper (VED) represented by the Kelvin model and the viscous fluid damper (VFD) represented by Maxwell model are proposed using the principle of minimizing the average vibration energy of either the single tower or the twin tower. Three pairs of representative numerical examples of twin-tower-connected structures are used to verify the correctness of the theoretical approach. The optimum parametric analysis demonstrates that the control performance is not sensitive to damper damping ratio of VED and relaxation time of VFD. The effectiveness of the proposed control strategies based on the 3-SDOF models is also proved to be applicable to multi-degree-of-freedom systems. The theoretical analysis and numerical results indicate that the seismic response and vibration energy of the twin-tower-connected structures are mitigated greatly under the two types of dampers. The presented control strategies of VED and VFD can help engineers in application of coupled structures.     

SEISMIC RESPONSE OF REINFORCED CONCRETE FRAMES INFILLED WITH WEAKLY REINFORCED MASONRY PANELS

The research work presented in this paper is related to the seismic response of RC frames infilled with weak masonry panels, as it is traditional in many seismic prone countries in southern Europe. More specifically, the benefits derived from the insertion of a light reinforcement, in the mortar layers or in the external plaster, are studied in some detail.

Tests have been performed on different types of single bay, single storey, infilled frames to investigate the in-plane response at different earthquake intensity levels and the out-of-plane strength as a function of the in-plane damage. A series of parametric simulations have then been performed, calibrating the models used in the test results, to evaluate the effects of the different panels characteristics on the response of whole buildings, with different infill patterns. Both in-plane and the out-of-plane response have been considered. The results are described in terms of peak ground acceleration required to induce given limit states of serviceability or damage relatively far from the collapse of the structure, which is governed by the RC frame design more than by the infill panels properties.     

Exploring normative whiteness: ensuring inclusive pedagogic practice in undergraduate fieldwork teaching and learning

Higher education commentators have become concerned about how learning and teaching praxis across the sector may unwittingly advantage White British (WB) compared to Black and Minority Ethnic (BME) students. Adopting critical race theory, this article explores these issues in relation to field teaching in geography and related subjects. It reports on primary data collected from students about to attend their first residential field trip. The research shows that WB and BME students approach their first field trip with diverse geographical experiences. The findings indicate a need to reflect critically on our fieldwork routines in order to promote inclusivity in field learning.     

WHITE,FRIEDLÄNDER, “… AND THE REST IS HISTORY”: A PAX HISTORIANA

Close analysis of the ostensive disagreement between Saul Friedländer and Hayden White on the necessarily literary character of Holocaust historiography shows instead of conflict two compatible and even mutually supportive emphases in that project: the assumption in modernist and disruptive narratives as elsewhere of a “corpus of facts,” together with the role of figurative discourse in conveying relevant features of events that linear chronological or causal narratives alone do not convey.     

单檐歇山式木构古建抵抗极端烈度地震试验调查研究

为更好地保护我国古建筑,基于《单檐歇山式古建筑抗震性能振动台试验》的相关成果,研究了强震作用下我国明清官式木构古建的抗震性能,制作了与该论文相同的试验模型,进行了振动台试验。通过对模型输入烈度逐渐增强的1940年El-centro波,并考虑地震波为水平双向作用,分析了强震作用下不同构造的试验现象,开展了详细的震后调查,获得了不同构造在强震作用下的抗震性能和震害机制。结果表明:强震作用下,我国明清官式木构古建的振动形式表现为柱架、斗拱、梁架及屋顶的近似同步往复摇摆;主要震害包括柱底偏移、榫卯节点开裂、拔榫、斗拱偏移及错位、额枋-垫板分离、墙体倒塌等,但承重木构架受损不严重,结构未产生倒塌。其良好抗震性能的原因与古建筑的构造特征密切相关。     

Spying in the British Post Office,Victorian Politics and Wilkie Collins’s The Woman in White

In 1844, the British public learned that the government was secretly opening exiled Young Italy leader Giuseppe Mazzini’s private letters and sharing information with continental authorities. For outraged citizens, espionage in that quintessential liberal institution, the reformed British Post Office, appeared un-English, despotic and criminal, the makings of a Gothic plot. Representations of the Post Office Scandal in Parliament and print predict the revision of the Gothic into the sensation novel that occurred with the publication of Wilkie Collins’s The Woman in White. Attention to the fields of Anglo-Italian studies, mid-Victorian print culture and the development of narrative form in the mid-nineteenth century illustrates the historical and political implications of letter-opening for the emergence of a new fictional genre. The Post Office Espionage Scandal and The Woman in White share a central place in a mid-Victorian moment of evolution in the mutually constitutive relationship between Italian and British national identities, producing and reflecting a crisis in Britishness focused on the secret tyrannies concealed beneath the surface of Victorian liberalism. The letter-opening scandal reveals a crisis in Victorian liberalism in the political realm and the media, while The Woman in White translates this Victorian crisis of confidence into a literary genre defined by exposing the sordid undercurrents of British society: sensation fiction. Together, the espionage scandal and Collins’s novel respond to and generate a challenge to Victorian complacency that emerged out of the collision of British and Italian politics and culture in the mid-nineteenth century.     

Presidential Oral History: The Clinton Presidential History Project

Most conventional oral history takes a bottom-up approach tothe past, focusing on settings where there is little in theway of a functional written record. This essay discusses thevalue of oral history in the opposite case of the American presidency.The written archive and journalistic record on each presidentis immense. Yet oral history is a valuable resource in thiselite environment, too. There are routine silences in even thebest of presidential papers, which oral history interviews canhelp fill. Moreover, the White House has become a workplacewhere recorded details can be hazardous to one's political health.Accordingly, few presidential aides today keep diaries or notesof key meetings—impoverishing the archive future historianswill use to study the presidency of our times. Oral historythus fortifies a weakening documentary record. This essay exploresthese broad issues and how they are being dealt with in theconduct of the William J. Clinton Presidential History Project.