铁路用变压器

简述日本欧洲铁路的电流制及列车的牵引方式,着重介绍机车车辆用主变压器以及日本、欧洲开发高温超导主变压器的情况.     

A trace metal (Pb, Cd, Zn, Cu) balance for surface waters in the eastern Gotland Basin, Baltic Sea

Trace metal inventories and transboundary fluxes were estimated for the surface waters of the eastern Gotland Basin, and a mass balance for this water body was derived.The study area was delineated by a box which bordered vertically by the sea surface and the halocline and horizontally by the coast of Gotland and the coast of Latvia/Lithuania. For the calculation of the trace metal inventories in the box, a high-resolution sampling was carried out during different seasons. Additional sediment trap studies were performed to calculate the vertical particulate trace metal fluxes through the halocline.The following transboundary fluxes have been estimated: (a) atmospheric input of trace metals; (b) lateral transport from adjacent bodies of surface water; (c) diapycnal fluxes of dissolved trace metals at the halocline; (d) sinking of trace metals, associated with particles, through the halocline, (e) vertical advection through the halocline.The lateral transport into and out of the surface box is important for the metals (Cd, Cu, Zn) with “nutrient-like” behaviour. For particle reactive elements like lead, vertical sedimentation and lateral transport out of the box as much as atmospheric input and lateral input into the box are in the same order of magnitude. Turbulent diapycnal mixing plays a minor role compared to the advective fluxes.The estimated range for the residence times for the region under investigation are  0.5–1.3 years for Pb;  2–11 years for Zn,  7–36 years for Cd and 42–89 years for Cu. This demonstrates that the system reacts very fast for particle reactive elements like Pb, while for copper sedimentation processes are not the preferential sink and can be neglected.     

夯能和夯击次数在西部山区公路填方路堤中的应用

文章介绍了强夯法在国内外研究和应用的现状,结合强夯在西部山区填方路堤再压实的试验,分析了夯能和夯击次数对填方路堤沉降量的影响,提出了不同夯能条件下夯击次数的具体取值范围,为今后同类工程的设计和施工提供参考。     

中国古代有无科学的争论及其意义--兼评《西方科学的起源》

关于中国古代有没有科学的争论 ,近年国内不少著名学者都曾卷入。迄今为止 ,双方当然未能取得一致意见 ,很可能永远也不会取得一致意见。然而这场争论有着明显的现实意义。而《西方科学的起源》(The Beginnings of Western Science)一书中译本在 2 0 0 1年的出版 ,则对于澄清争论中的某些概念大有帮助 ,值得论战双方都仔细一读     

蒙华铁路货车段修能力探讨

阐述客货分线后铁路货运能力增强、货车保有量增长的特征,以及铁路货物高效率高质量的运输需求,必然会对货车段修能力提出新的要求。采用调研货车保有量、货车段修台位方法,结合货车保有量预测,分析全路及蒙西至华中煤运通道铁路(简称"蒙华铁路")沿线区域内货车保有量增长与货车段修能力的矛盾,提出新建(或扩建)车辆段、加强检修工艺装备、优化组织管理、修程修制改革等货车段修能力增强措施,提出蒙华铁路货车车辆段(检修车间)设施布局方案,分析沿线区域货车段修能力增强措施。     

CD147蛋白在人宫颈癌中的表达

目的 探讨CD147在宫颈癌中的表达及其意义.方法 应用蛋白印迹及免疫组织化学方法检测CD147在宫颈癌和正常宫颈组织中的表达.结果 CD147蛋白在所有的宫颈癌(41/41,100.0%)和绝大多数正常宫颈组织(11/12,91.7%) 都表达.宫颈组织中存在着不同分子量的CD147分子.CD147在宫颈癌中的细胞阳性率及表达量都要显著高于正常组织(P<0.05).结论 CD147是细胞增殖的一个标记分子;CD147 蛋白在宫颈癌中高表达,是宫颈癌治疗的一个潜在靶点.     

西方的汉学研究与中国人文学术的国际化

在当前的全球化语境下,对海外汉学的研究再度成为一个热门话题。虽然汉学在西方学界长期处于边缘地位,但由于其研究方法的独特和理论视角的新颖,汉学研究一直颇受国内学界青睐。本文作者认为,我们一方面要认识到汉学深受西方学界风行已久的东方主义的影响,存在着对古代中国的种种幻象和对现代中国的误解甚至歪曲,但另一方面又应该承认,西方的汉学界并不乏具有真才实学的大家,他们的重要研究成果对国内学界也有着启示。再者,与东方主义所不同的是,汉学中也存在着"去政治性"和"去意识形态性"的倾向,它和国内学者的国学研究应该形成一种对话和互补的关系,特别是当我们在把中国文化的成果推向世界的过程中,我们就更离不开与汉学家的通力合作。     

Climate Change and Tourist Comfort on Europe's Beaches in Summer: A Reassessment

Major impacts of climate change have been projected for tourism in Europe. Typically, these projections took general tourism activities such as sight-seeing and their climate requirements as their point of reference. The purpose of this study is to reassess the impact of climate change, by looking specifically at beach tourism in summer, a crucial market segment in Europe and more specifically in the Mediterranean. As beach tourism requires relatively high temperatures, relatively modest shifts in attractiveness are found. With respect to climate, the Mediterranean is likely to remain Europe's prime region for summer-time beach tourism for at least the next 50 years. Coastal managers in Mediterranean destinations are advised to focus some of their attention on other climate change impacts such as sea-level rise or water availability, and include environmental quality and diversification of activities in their deliberations. In non-Mediterranean regions, a promising strategy may be to focus on short- and medium-distance visitors who can take advantage of the new opportunities for beach tourism, and to explore the merits of seasonal climate forecasting.     

Environmental invitingness for transport-related cycling in middle-aged adults: A proof of concept study using photographs

IntroductionCurrent evidence on associations between modifiable environmental characteristics and transport-related cycling remains inconsistent. Most studies on these associations used questionnaires to determine environmental perceptions, but such tools may be subject to bias due to unreliable recall. Moreover, questionnaires only measure separate environmental characteristics, while real environments are a combination of different characteristics. To overcome these limitations, the present proof of concept study used panoramic photographs of cycling environments to capture direct responses to the physical environment. We examined which depicted environmental characteristics were associated to environments’ invitingness for transportation cycling. Furthermore, interactions with gender and participants’ cycling behavior were examined.MethodsFifty-nine middle-aged adults were recruited through purposeful convenience sampling. During a home visit, participants took part in a structured interview assessing demographics and PA during the preceding seven days, followed by an intuitive choice task and a (cognitive) rating task, which both measured 40 photographed environments’ invitingness to cycle along. Multi-level cross-classified analyses were conducted using MLwiN 2.26.ResultsBoth tasks’ multivariate results showed that presence of vegetation was identified as the most important environmental characteristic to invite people for engaging in transportation cycling, even when the amount of vegetation was relatively small. In the bivariate analyzes, some differences between results of the cognitive rating task and the intuitive choice task were found, showing that invitingness measured by the rating task was associated with environmental maintenance and cycling infrastructure, whereas invitingness determined by the choice task was associated with more traffic-oriented characteristics. Moreover, only for the choice task’s results, moderating effects of gender and participants’ cycling behavior in the preceding week were observed.ConclusionThe present study provides proof of concept that capturing people’s less cognitive, more intuitive responses to an environment’s invitingness for transport-related cycling may be important for revealing environment-behavior associations. If replicated in future studies using larger samples, results of our innovative measurements with photographs, especially those on vegetation, can complete the existing knowledge on which environmental characteristics are important for transportation cycling in adults and could form a basis to inform health promoters and local policy makers. However, future studies replicating our study method in larger samples and other population subgroups are highly encouraged. Moreover, causal relationships should be explored.     

Competition and public service obligations in European aviation markets

This paper analyzes the effect of universal service policies on the airline markets of five European Union countries (France, Germany, Italy, Spain and the United Kingdom) in the period 2002–2010. Results show that airfare discount schemes for island residents raise demand and positively affect competition and the number of flights at the route level. These effects are evident in France and Italy, but are particularly marked in Spain. By contrast, public service obligations (PSOs) reduce competition on the protected routes, while their effect on the number of flights differs depending on national regulations. In Spain, routes protected with PSOs have greater flight frequencies than those on unprotected routes of similar characteristics, but in France, Italy and the UK the opposite result is found. The empirical model also finds that on routes with low-cost airlines market concentration is smaller and there is a larger number of flights. This result is relevant for the design of universal service policy, since in recent years low-cost airlines have entered a number of thin routes and have increased access to air transportation.