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91.
在描述辽宁省东部山区公路水毁现状、分析水毁成因的基础上,结合山区公路设计、建设、养护实际,提出东部山区公路水毁防治措施建议。 相似文献
92.
93.
张妮媛 《重庆交通大学学报(自然科学版)》2007,26(Z1):164-165
通过对一系列城市题材的分析,说明在创作中色调和表现形式应该与表现题材的内涵相一致,同时分析了当代水彩画家对水彩综合技法和材料所作出的探索. 相似文献
94.
结合室内研究成果和工程应用经验,提出了泡沫沥青冷再生混合料的设计方法。设计内容包括:材料与级配设计、沥青及沥青发泡特性、拌和用水量的确定、试件的成型与养护、泡沫沥青最佳用量的控制指标讨论以及泡沫沥青最佳用量的确定方法等。通过实践应用证明这种基于水稳性的泡沫沥青混合料配合比设计方法可作为室内研究和工程应用的主要指导依据。 相似文献
95.
摘通过对辽宁“十五”期间的水运发展状况研究,总结了发展经验,分析了辽宁水运发展存在的问题和不足。在此基础上,提出了“十一五”辽宁水运的发展目标,并就保障水运发展的措施提出了自己的见解。 相似文献
97.
车辆的外廓尺寸是公路几何设计中的重要控制因素。《公路工程技术标准》明确规定了设计车辆的种类及其外廓尺寸,作为确定道路交叉布置和道路几何形状的基本依据。而实际上因某些特殊需要,公路上经常出现外廓尺寸超出设计车辆最大尺寸范围的超长车辆,现行路线规范中平曲线加宽值不能满足其转弯要求。结合水东服务区设计实例,对超长车辆转弯时平曲线半径加宽值验算进行详细论述,具有一定的实际意义。 相似文献
98.
Alessandra Cincinelli Tania Martellini Lucilla Bittoni Aniello Russo Andrea Gambaro Luciano Lepri 《Journal of Marine Systems》2008,73(1-2):208-220
In the framework of the Italian Research Programme in Antarctica (PNRA) an oceanographic cruise was carried out between December 2000 and February 2001 in the Western Ross Sea. n-Alkanes and PAHs concentrations were analysed in sea-water samples collected at different depths at four sites (D, B, CA2, and CA). Vertical profiles of pressure, temperature, salinity and fluorescence were also performed in order to distinguish the water masses present in the sampling areas. n-Alkanes concentrations were consistent with those found in the same area during previous expeditions and showed higher values in the particulate due to the low temperatures. n-Alkanes profiles exhibited different features in the dissolved and particulate phases. The dissolved phase was characterised by a bimodal distribution with two maxima at C16 and C24 and prevalent compounds in the range C15–C32 whereas particulate was strongly dominated by long chain n-alkanes C23–C34 with C24 (Site B, CA and CA2) or C32 (Site B) as Cmax. CPI values and Pr/Ph ratios suggested a prevalent biogenic origin for aliphatic hydrocarbons. n-Alkanes vertical distributions were affected by the dynamic of the pack-ice melting and phytoplankton activity as well by the chemical–physical properties of water masses. Higher n-alkanes values were found in the High Salinity Shelf Waters (HSSW), lower n-alkanes values were found in the Antarctic Surface Waters (AASW) and Modified Circumpolar Deep Water (MCDW).The low PAHs concentration levels confirmed the still pristine character of the Antarctic environment. Neither particular trend in total PAHs concentrations along the water column and nor correlations with the most characteristic water masses of the investigated area of the Ross Sea were observed, except that total PAH higher concentrations were generally observed in correspondence of HSSW. 相似文献
99.
The red shrimp Aristeus antennatus is one of the target species of the bottom trawl fishery of the Balearic Islands. The objective of the present paper is to study the short spatial and temporal differences of this important economic resource between two different locations off Mallorca (Cabrera: CA; Sóller: SO), where a fleet mobility pattern has been detected, and to study the influence of environmental conditions on this species. Six simultaneous bottom-trawl and oceanographic surveys were carried out at these two locations in order to collect data from the demersal species, hydrography (temperature and salinity), trophic resources and sediment characteristics. The commercial fleet from both locations was monitored by monthly on-board sampling, log-books and daily landings obtained from sales slips. Additional data was obtained from other fishing surveys. Short spatial and temporal differences have been detected between both locations. The population at CA was more demographically homogeneous, while that at SO showed important variations, like high abundance of juveniles recruiting to fishing grounds in autumn–winter and high abundance of large females during summer. Several differences have also been found in the biology of the species between locations, such as males were more abundant in SO than in CA. Also, the reproductive period started sooner in SO than in CA, and the condition of pre-spawning females was better in SO. The percentage of total lipids in the hepatopancreas was minimal during the spawning period, showing their importance as a reserve of energy for the ovary ripening. Water masses could play an important role in these differences, the characteristics of water masses being more stable in CA than in SO. Red shrimp adult females seemed to be more correlated with the warmer and more saline Levantine Intermediate Waters, while juveniles (males and females) and adult males were more correlated with the colder Western Mediterranean Deep Waters, detected only in SO during autumn–winter. Two different hypothesis of mobility patterns for the species are discussed in relation to these observed differences. 相似文献
100.
本文报告用彩色多普勒检测151例颈动脉粥样硬化病变和34例正常人。结果表明颈动脉分叉处是粥样硬化斑块多发部位(62.3%),声像图显示斑块有3种类型(扁平斑、软斑、硬斑)。本组中有6例颈内动脉腔明显狭窄(腔径减少45%以上),狭窄部位显示有镶嵌血流。频谱多普勒分析显示收缩期峰值流速增高和频谱增宽。2例颈内动脉完全阻塞,彩色多普勒显示颈内动脉内无彩色血流。这种方法可用于颈动脉粥样硬化的早期诊断,也对缺血性脑病的预防具有价值。 相似文献