首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
实验装置通过一对带电平行金属板形成匀强电场,由可控带电液滴装置提供带电粒子,整个装置封闭在一个外壳中.该装置可以演示带电粒子在匀强电场中的加速、偏转现象,探究带电粒子在匀强电场中偏转运动的偏转量与哪些因素有关,探究平行板电容器的电容与哪些因素有关等.阐述了装置的原理,分析了装置的构成及其在教学中的应用方法.  相似文献   

2.
实验装置通过一对带电平行金属板形成匀强电场,由可控带电液滴装置提供带电粒子,整个装置封闭在一 个外壳中.该装置可以演示带电粒子在匀强电场中的加速、偏转现象,探究带电粒子在匀强电场中偏转运动的偏转 量与哪些因素有关,探究平行板电容器的电容与哪些因素有关等.阐述了装置的原理,分析了装置的构成及其在教 学中的应用方法.  相似文献   

3.
运用相对论原理分析出带电粒子在均匀电场中的运动轨迹是悬链线;在均匀磁场中的运动轨迹是螺旋线;当电磁场并存时,带电粒子在均匀电磁场中的运动与电场强度和磁感应强度的大小、方向有关,其运动轨迹并非两者的叠加,而是旋轮线或双曲线.  相似文献   

4.
在均匀电磁场中带电粒子的相对论运动分析   总被引:1,自引:0,他引:1  
该文对带电子在电场、磁场以及电磁场中的运动进行分析并在四维闵可夫斯基空间,对带电粒子在电磁场中的相对论运动进行求解.  相似文献   

5.
通过对不同电磁场环境中的带电粒子受力情况研究带电粒子的运动规律。带电粒子只受电场或只受磁场作用时,其运动轨迹分别是抛物线或螺旋线。当带电粒子受电磁场作用时(带电粒子初速度、电场与磁场两两相互垂直或磁场垂直于初速度与电场构成的平面且初速度与电场成任意角度),得出带电粒子的运动方程。  相似文献   

6.
将带电粒子在非均匀磁场中的运动看成是在均匀磁场中的回旋。进而描述磁场的非均匀性,具体的分析了仅有散度项、曲率项、梯度项不等于零的磁场。介绍一种常见的喇叭形非均匀磁场,讨论了带电粒子在喇叭形磁场中的螺旋轨道半径、纵向速度分量以及运动的角度与磁场的关系和磁约束原理。目的是加深带电粒子在非均匀磁场中运动的理解。  相似文献   

7.
文章首先简要回顾带电粒子在均匀磁场中的运动,其次重点分析带电粒子在非均匀磁场中的运动,最后说明等离子体的磁约束问题。  相似文献   

8.
基于经典洛伦兹力方程,对带电粒子在正交时变电/磁场及平面波电磁场作用下的运动规律进行了研究;通过方程的解,分析了带电粒子在静场、时谐电场、时谐磁场、正交时谐电/磁场及平面电磁场等几种典型情况下的运动特性;结果表明:粒子在不同的条件下有不同的运动规律,除少数情况外,在电场方向都存在周期运动,但静场与时变场的周期不同;沿波矢方向的速度与电场方向的速度满足圆方程关系;在平面波时,粒子电场方向的速度满足波动方程;在高频场中,粒子主要受初值条件的影响;结合数值仿真,模拟了带电粒子运动的一般轨迹并讨论了经典洛伦兹力方程的适用性。  相似文献   

9.
简要分析了在考虑重力作用的情形下,带电粒子在恒定磁场和振荡电场中的运动状态,求得了其运动方程,并就拉莫频率和振荡频率的关系进行了讨论.  相似文献   

10.
从哈密顿正则方程出发,推导出了带电粒子在相互垂直的电场和磁场中的运动方程,根据运动方程讨论了带电粒子的运动轨迹形成闭合轨道所满足的条件.计算结果表明:随着带电粒子能量的不断增大,带电粒子运动轨迹中闭合轨道的条数不断增多.当能量增加到某一边界能量时,一条新的闭合轨道出现;当能量大于此边界能量时,这条新的闭合轨道发生分叉,由一条分为两条.  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.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号