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1.
英语中的惯用语相对而言有一般与特殊之分,一般说来,对于一般且常见的部分,我们不难理解与翻译,而对于其中特殊的部分,不论是学习者,还是外语工作者均视其为理解与翻译的一个难点,因此很有探讨的必要。  相似文献   

2.
反意疑问句是一种常用于口语的疑问句式,也是中学阶段一个常考的知识点,主要由“陈述句+附加问句”构成,反义疑问句部分的动词一般要与陈述部分的动词相对应,反义疑问句部分的主语要与陈述部分的主语相对应,如果陈述部分的主语是名词词组,则反意疑问句部分用相应的代词表示。那么下面就谈谈反意疑问句的考点有哪些?  相似文献   

3.
田献珍 《科技信息》2012,(34):492-492
1.独立学院开设《MATLAB软件》课程的必要性MATLAB软件包括公共核心部分与专业工具箱部分等产品系列,核心部分有数百个公共内部函数,工具箱部分有多种专业扩充功能,正是这些功能被广泛应用于科学与工程计算。实践证明,MATLAB用于解决以下领域中的各种计算问题十分有效,诸如电子学、控制理论、物理学、经济学、化学和生物学等有计算问题的所有领域,而这些学科都有很强的应用性,一般的独立学院都有开此类课程。另外,独立学院的学生普遍头脑灵活,重视社会实践,比较注重个人能力素质的提高,对知识应用于实践的要求比较高,因此,对于独立学院开设(MATLAB软件》课程就显得非常必要。  相似文献   

4.
研究了一类非线性连续时变控制系统的部分镇定问题.利用Lyapunov部分稳定性理论和M-矩阵的性质,构造出了几个镇定控制器。其中一些控制器仅与系统的部分状态变量有关,所构造的控制器可确保反馈后的闭环系统是部分渐近稳定的,所得结论推广了有关文献中的相应结果.  相似文献   

5.
集聚纺集聚区须条变截面部分的力学分析   总被引:1,自引:2,他引:1  
通过对集聚区内须条的集聚过程分析,建立须条变截面部分的力学模型,可以得出此部分须条是有附加捻度的,并且对影响这部分须条附加捻度的因素:须条与网格问的摩擦因数和负压的大小进行了分析,结果表明集聚区须条的附加捻度随着须条与网格问的摩擦因数和负压的增加而增加。  相似文献   

6.
通过对自然人群血栓状态和部分生化指标的检测,采用常规的统计分析,推断出正常人体外血栓参数的临界值分别为:长度36.83mm,干重42.44mg,线密度2.28g.m^-1,血栓状态与血液内的部分生化指标有弱的相关,分别是胆固醇与线密度相关,甘油三酯与血栓长度相关,β-脂旦白与干重相关。  相似文献   

7.
分析了一类具有时变不确定性的互联系统.结果表明,系统的确定部分是可镇定的,不确定的部分被假设为满足匹配条件,而且不确定部分具有锥形界,但此界未知.基于与不确定界有关的确定性质进行控制设计.反馈信息具有测量误差的状态进行控制设计.  相似文献   

8.
实验研究红鳍东方Tun精子形态的超微结构:红鳍东方Tun表子分头部和尾部等两部分。头部似炮弹状,无顶体;核内有空隙,空隙中有或无少量电子致密小颗粒:细胞膜与核膜间的原生质有向外鼓起的单个小液泡;中心粒复合体位于植入窝内,由近端中心粒、中心粒间体和基体等组成。袖套位于核后端,内含7-8个环列的线粒体球。尾部近端部分鞭毛的一侧有小囊泡群聚的囊泡鞘;远核部部分有侧鳍;胞鞘和侧鳍与轴丝的中央微和同在“Y”  相似文献   

9.
Q&A     
《科学世界》2014,(3):102-103
我们的耳朵由外耳、中耳和内耳三个部分组成,中耳是传导声波的主要部分。鼓室是中耳的核心组成部分,它是一个不规则的空腔结构,体积不超过2毫升,有上、下、前、后、内侧、外侧共六个壁,各壁都有其不同性质的重要结构,功能也各不相同。在鼓室的前壁上,有一个小孔通向一条直接与外界相通的管道,  相似文献   

10.
杭金菊 《科技信息》2009,(26):187-188
形势与政策课在高职院得到了较为普遍的重视和加强,收到了良好的教学效果。但部分高职院的形势与政策课的教学质量和教学效果尚不尽如人意,高职生对这门课程的教学还有一些意见和情绪,部分任课老师对课程教学的认识也有一些困惑和迷惘。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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