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1.
弯管一次合成设备   总被引:4,自引:0,他引:4  
研制了用于弯管一次合成的设备,该设备由三部分组成,主体部分,控制部分和监视部分,主体部分包括电动机,减速箱,安装盘和机架,控制部分包括温度检测仪,调速器和计算机,监视部分包括电视和摄像头,使用该设备可实现弯管一次合成过程的全自动控制,并合成出Φ325mm的陶瓷复合弯管。  相似文献   

2.
试论被动化转换的语义差异邵伟国,许小平根据乔姆斯基的语法纲领,“凡是一种语言,其语法都包括句法部分,语义部分和语音部分。语义部分和语音部分纯然是传译性的,对于句子结构的递归生成,这两部分毫无作用。句法部分由基础和转换部分构成.基础又由范畴次部分和词汇...  相似文献   

3.
部分半群的分解   总被引:3,自引:3,他引:0  
对部分半群的分解性质进行研究,得到了部分半群分国不同分解,互不相乘,互不相交的子部分半群的并的存在唯一性定理,并对部分半群定义了有向图,使得无假孤独元的不可分解部分半群与连通有向图对应,无假孤独元的部分半群的极大不可分解子部分半群与它的有向图的连通分支一一对应。  相似文献   

4.
《增订注释全宋词》部分注释有误,部分注释不准确,部分该注而未注,部分校对有误,亦有极少数印刷失误。  相似文献   

5.
重视放松活动在体育教学中的作用   总被引:1,自引:0,他引:1  
王虔  苏龙艳 《科技资讯》2006,(34):91-93
学校体育课堂教学是由准备部分、基本部分和结束部分组成,这是符合学生的心理和生理特点。然而现在有些学校体育教师只重视准备部分和基本部分的教学,忽视了结束部分整理放松活动,从而导致学生的心理和生理的负担加重,危害了学生的身体健康,直接影响其他课程的学习效果,这也就偏离了学校体育教学的目的和任务,应引起体育教育工作者的高度重视。  相似文献   

6.
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   

7.
基于小波的信号部分重构与插值   总被引:3,自引:0,他引:3  
通过分析信号重构理论,提出了信号部分重构的概念,即已知原信号的部分信息,通过增加一些新信息可以重构原信号更进一步的逼近,而且信号部分重构过程的迭代将达到信号的完全重构。基于小波变换理论,研究了一类信号部分重构问题,得到了一种信号部分重构公式。从信号部分重构的观点出发,提出了一种能够消除假频并扩展频宽的地震信号空间插值办法,实验结果证实了方法的有效性。  相似文献   

8.
克氏原螯虾触角腺的组织学研究   总被引:2,自引:0,他引:2  
本文利用石蜡切片技术对克氏原螯虾触角腺进行了组织学研究,结果表明,克氏原螯虾触角腺可分为端囊、迷路和肾管三部分,端囊部分的细胞呈柱状,细胞核位于基部;迷路部分细胞也呈柱状,其顶端具刷状缘,核位于细胞的基部或中部,迷路部分可分为二个亚区;肾管部分的细胞呈柱状或较为扁平,核位于细胞的中部或靠近细胞顶端,肾管部分可分为三个不同亚区。  相似文献   

9.
雁来红叶色转变与超微结构及色素含量的关系   总被引:13,自引:0,他引:13  
当秋季来临,日照变短时,雁来红同一叶片的颜色逐渐从基部向顶端上紫色变成鲜红色,紫叶部分的细胞中,叶绿体结构完整,有丰富的线粒体及其它细胞器;红色部分的细胞中,叶绿体肿胀,基粒消失、基质片层变得松莠,叶绿内积累一些滴和结晶状内含体,紫色部分的叶绿素a;叶绿素b=2.77,叶绿素总含量为6.07mg/gF.W,红色部分不含叶绿素,两部分的花色素含量相近。  相似文献   

10.
关于部分变元正定的李雅普诺夫函数是研究系统关于部分变元稳定性的有力工具,本文引入了关于部分变元正定的概念,研究了二次型关于部分变元正定的充分,必要条件,并给出几个便于判断的必要条件。  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.
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   

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 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   

15.
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   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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