公路除雪及安全技术的研究

文章介绍了西部交通科技建设项目公路除雪及安全技术研究的目的意义、技术成果,为我国寒冷地区冬季道路养护提供了一套经济有效的除雪防滑技术,其研究成果具有推广应用价值。     

交通科技进步对西部经济发展贡献率的实证研究

文章以贵州、广西两省公路和水路运输行业发展中科技进步作用的定量测算为实证,结合发展经济学的理论基础和西部地区的实际情况,利用生产函数的经济增长模型,研究交通行业科技进步与西部地区经济发展的关系。     

KCNE2蛋白在自发性高血压大鼠心脏组织中的分布和表达

目的研究KCNE2蛋白在自发性高血压大鼠(SHR)心脏不同部位的分布和表达差异,及鼠龄对其表达水平的影响。方法提取幼龄和高龄SHR心肌不同部位(心室、室隔膜和心房)组织的膜蛋白,利用Western印迹技术和图象分析方法,比较KCNE2蛋白在样品之间免疫强度差异。结果SHR心肌不同部位组织中均有KCNE2蛋白的分布;同龄大鼠心肌不同部位组织中KCNE2蛋白的表达均无显著性差异;但在高龄大鼠的右心室和室隔膜组织中,KCNE2蛋白的表达显著高于其在幼龄大鼠相同组织中的表达。结论KCNE2蛋白在SHR心脏不同部位均有分布;在高龄大鼠右心室和室隔膜组织中,KCNE2蛋白的表达水平均高于其在幼龄大鼠同一组织中的表达。     

东方物流与西方Logistics

东方物流与西方Logistics在理念上存在着显著差异,东方物流理念强调从供给方向需求方的转移,注重物流的物理性移动,而西方Logistics理念则强调对供应链全过程的管理.本文试图通过对东方物流的产生背景、基本理念及运作方式与西方在二战后被经济界和企业家引用的Logistics的思想进行比较,探讨经济全球化之后东西方如何在供应链管理上进行融合,形成经济物流(Economic Logistics)^①.     

欧洲集装箱内河运输经验借鉴

随着全球和区域经济网络的形成和发展,内河集装箱运输得到了迅猛发展,人们日趋认识到内河集装箱运输在集装箱多式联运体系中的重要价值和未来持续增长的潜力。为此,以欧洲集装箱内河运输经验为借鉴,对集装箱内河运输模式进行了分析,内容包括:内河集装箱发展演变特点、给予政府层面的集装箱内河运输推进模式等,在此基础上,对我国的内河集装箱运输,提出了若干建议。     

Deregulating European aviation — A case study

European international scheduled aviation has been characterised by bans on market entry, price collusion, and capacity sharing. High fares were charged compared to world standards and the fares charged by European charter airlines.In May 1986 new entrants with pricing freedom were permitted on the London-Dublin route which was then the third largest in European scheduled international aviation. Prior to deregulation the route experienced high fare growth. The unrestricted fare ex-London increased 72.6 per cent compared to a Retail Price Index increase of 41.5 per cent. There was a growth in passenger numbers in the years 1980–85 of 2.8 per cent.Since deregulation passenger numbers have risen to 2.3 million compared to 994,000 before deregulation. Fares have declined by an estimated 37 per cent ex-Dublin and 42 per cent ex-London in real terms. There have been four cases of market entry and one of market exit. The estimated share of the new entrants in the second half of 1989 was 28 per cent. The preregulation earnings data of Aer Lingus, the market leader, indicated that protection allowed staff to earn economic rents. A two-tier structure was introduced in response to competition.Remaining barriers to contestability in UK/Ireland aviation include hub airport dominance, ground handling monopolies, and the ability of airlines with routes in both regulated and deregulated markets to engage in geographical price discrimination against airlines with routes in deregulated markets only. A pro-contestability aviation policy in Europe will require measures to prevent the abuse of dominant positions by established airlines over new market entrants and to prevent collusion between established airlines.     

大鼠栓塞肺组织中代谢相关酶类的表达变化

目的研究大鼠急性肺栓塞模型肺组织中部分代谢相关酶类的表达变化。方法建立大鼠急性肺栓塞模型,分别在急性肺栓塞后1、8、244、8 h提取肺组织的总RNA和总蛋白,以正常组为对照,采取半定量RT-PCR的方法研究3-磷酸甘油醛脱氢酶(GAPDH)、儿苯酚胺氧位甲基转移酶(COMT)、衰老标记蛋白-30(SMP-30)、3-α-羟类固醇脱氢酶(SDH)和延胡索酰乙酰乙酸水解酶(FAH)在mRNA水平的表达变化;采用Western-blot方法进一步验证GAP-DH和COMT在蛋白水平的表达变化。结果大鼠急性肺栓塞后在不同的时间点,GAPDH、COMT、SMP-30、SDH和FAH的mRNA水平均逐渐减低,GAPDH和COMT在蛋白水平的表达也出现逐渐减低现象。结论大鼠急性肺栓塞后肺组织内大多数上述代谢相关蛋白均出现表达减低的现象。研究这些酶类的生物学功能和表达变化,将为我们阐明急性肺栓塞病理生理变化的分子机制奠定基础。     

国内外中重型商用车排放法规演变及对比

对美国、欧洲、日本和我国中重型车(大于35吨)排放法规的演变进行了详细介绍,并对不同阶段法规的限值和具体实施时间进行了对比;最后还对世界上以欧盟汽车排放阀规体系为参照标准,并执行对应标准限值的主要国家中重型车不同阶段法规实施时间进行了对比.     

清代中西文化互动及其终结初探

在清代,中国化出现了一次明显的转向,一方面是中国化研究力求改变宋明以来,崇尚空谈的学术风气,力图重建社会与思想秩序;另一方面则是中西明之间所发生的大规模的相遇和互动,这种互动最后以失败而告终。本旨在证明：异质化间的有益互动只能建立在彼此深入理解、以平等身份参与的基础之上,各种化形态都应当历史地反思自身在人类明发展史中的态度选择。     

Parameterisation of clastic sediments including benthic structures

The sediment transport processes in the south-western Baltic Sea are predicted by means of a numerical model in the project DYNAS. There are two sediment parameters that influence the results of modelling remarkably: critical shear stress velocity and bottom roughness. This paper presents the way how to parameterise these factors and extrapolate them into the investigation area. The critical shear stress velocity is parameterised basing on grain size data, combining approximations after Hjulström [Hjulström, F., 1935: Studies in the morphological activity of rivers as illustrated by the river Fyris. Geological Institution of University of Uppsala: Bulletin (25): 221–528.], Shields [Shields, A., 1936: Anwendung der Ähnlichkeits-Mechanik und der Turbulenzforschung auf die Geschiebebewegung. Mitteilungen der Preussischen Versuchsanstalt für Wasserbau und Schiffahrt (26): 26 pp.] and Bohling [Bohling, B., 2003: Untersuchungen zur Mobilität natürlicher und anthropogener Sedimente in der Mecklenburger Bucht. unpublished doctoral thesis, Mathematisch-Naturwissenschaftliche Fakultät, Ernst-Moritz-Arndt-Universität Greifswald/Germany, 156 pp.]. The roughness length, in the case of absence of macro zoo-benthos and their structures, is parameterised basing on grain size too employing Soulsby [Soulsby, R.L., 1997: Dynamics of Marine Sands: a Manual for Practical Applications. London, Thomas Telford Publications. 249 pp.], Nielsen [Nielsen, P., 1983: Analytical determination of nearshore wave height variation due to refraction shoaling and friction. Coastal Engineering 7, 233–251.] and Yalin [Yalin, M.S., 1977: Mechanics of Sediment Transport. Pergamon Press, New York. 298 pp.]. No equivalent simple parameterisations for biologically caused bed roughness exist. Here, findings of Friedrichs [Friedrichs, M., 2004: Flow-induced effects of macro zoo-benthic structures on the near-bed sediment transport. Dissertation, Universität Rostock, 80 S.] and estimations by the DYNAS biologists group were combined in order to derive roughness lengths from abundance measurements of four previously selected key species which represent the originators of the dominating benthic structures at the sea floor in the south-western Baltic Sea. Critical shear stress velocity and bed roughness are known at few sample sites only. They were extrapolated into the larger investigation area using a proxy-target concept. The mean near bottom milieu (bathymetry, median grain size, salinity, oxygen) which was derived using results from numerical modelling serves as the proxy. Since the milieu parameters are measured at the sampling sites for which the target parameters have been determined, a combined hierarchical and supervised classification was employed to transfer the local knowledge into the unknown investigation area.