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141.
142.
试论日语和汉语中的同形异意词 总被引:1,自引:0,他引:1
徐暖 《浙江万里学院学报》2005,18(6):117-120
日汉同形异意词是日语学习的难点之一。文章拟从语意范围、褒贬色彩、词语搭配等角度出发,结合具体的实例来探讨日、汉两种语言中的同形词在各自的具体使用语境中的意义偏差。 相似文献
143.
144.
重新建立了电阻性本质安全电路电弧放电能量的计算公式 ,证明在评价电路的安全性能时 ,理论上将电阻性电路当作电感性电路的特例处理 ,存在着最大可达 1 2 .5 %的误差 实验发现当电路从电感性过渡到电阻性时 ,电弧放电开始瞬间电弧电流将突然下降 还发现对电感性电路 ,放电电流线性衰减模型仅适用于电感量为 1mH左右时的情况 最后对评价电路本质安全性能的计算方法进行了修正 图 8,参 6 相似文献
145.
王安忆在长篇小说《长恨歌》中塑造了程先生、康明逊、萨沙、老克腊、长脚几位男性小人物形象,他们与主人公王琦瑶有着密切的关系。作为都市小人物,他们存在着共性,同时他们又个性鲜明,形象各异,分别代表了痴情型、胆小懦弱型、小混混型的小市民。塑造这些都市男性小人物体现了作者鲜明的创作意图。 相似文献
146.
本文介绍了中文下拉式菜单的设计思想与实现技术,并以Tur-boC为工具,以UCDOS中16×16和24×24点阵字库为例编程进行了验证。 相似文献
147.
Hanane El Hajaji Nadya Lachkar Katim Alaoui Yahya Cherrah Abdellah Farah Abdesslam Ennabili Brahim El Bali Mohammed Lachkar 《Arabian Journal of Chemistry》2011,4(3):321-324
We evaluated the in vitro antioxidant property and phytochemical constituents of the crude ethyl acetate and methanol extract of the three genders of carob tree barks (spontaneous male, spontaneous female, and grafted female). The scavenging activity on DPPH (1,1-diphenyl-2-picrylhydrazyl) was determined, as well as the phenolic contents (Folin–Ciocalteu method) of both the extracts. The highest antioxidant activity and the higher amounts of total phenols were shown in methanol crude bark extract for the three genders. Variety significantly affected the phenol content and the antioxidant activity, with the spontaneous male variety globally showed a higher polyphenol concentration and antioxidant activity than the grafted female and spontaneous female. 相似文献
148.
In this paper, heavy crude oil–water flows are studied in a horizontal stainless steel test section with 25.4 mm ID and overall length of 50 m. Crude oil (viscosity = 628.1 mPa s, interfacial tension with water = 10.33 mN/m at 60 °C) and water, collected from an oilfield, were used as test fluids. Visual observations, local sampling and pressure drop measurements were used to identify the flow patterns and their transitions. It was found that in all conditions studied there was a water-in-oil emulsion present. At low mixture velocities and water fractions this occupied the whole pipe cross section. As the velocity or the volume fraction increased water appeared to segregate. At high water fractions and mixture velocities annular flow appeared with the water-in-oil emulsion in the core surrounded by a water layer. The results were compared with those from a model oil with the same viscosity. At low water fractions there was a similarity between the patterns observed with the two oil systems characterized by water segregation from an oil continuous dispersion with increasing water fraction or mixture velocity. However, at high water fractions an oil-in-water dispersion formed with the model oil that was not seen with the crude oil. Pressure drop was generally higher for the crude oil system compared to the model one, while in both cases it decreased when water started to segregate and form layers in contact with the pipe wall. The differences between the two oil systems are attributed to the natural surfactants present in the heavy crude oil (such as asphaltenes and resins), which tend to accumulate on the water/oil interface, retard film drainage and maintain the stability of water drops in oil. 相似文献
149.
磨西河流域泥石流流域形态的非线性特征 总被引:1,自引:0,他引:1
泥石流是磨西河流域地质环境演化的一个重要地表过程,研究该流域内泥石流的地貌发育及演化特征可为磨西河流域第四纪以来地质环境的演变提供重要信息。通过对流域51条泥石流沟地貌形态的统计分析发现,磨西河流域内泥石流的分布在空间上表现出明显的不均性,流域内泥石流沟的数量与对应的主沟长度、主沟纵比降及流域面积之间存在着明显的分形现象,具有较高的自相似性。结果表明,泥石流沟谷形态的非线性演化特征及现象是对磨西河流域冰川环境和地质构造环境响应的直接结果,主要体现在现代冰川对流域的强烈侵蚀和贡嘎山隆升而导致流域的强烈下切。研究结果可为流域内泥石流灾害的形成机理、防灾减灾及流域环境演化提供理论依据。 相似文献
150.
Tri Lai 《Discrete Mathematics》2021,344(7):112390
The author and Rohatgi recently proved a ‘shuffling theorem’ for doubly-dented hexagons. In particular, they showed that shuffling removed unit triangles along a horizontal axis in a hexagon changes the tiling number by only a simple multiplicative factor. In this paper, we consider a similar phenomenon for a symmetry class of tilings, namely, the reflectively symmetric tilings. We also prove several shuffling theorems for halved hexagons. 相似文献