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1.
分析了太阳重力场对核反应扩散系统稳定性及中微子产生的影响.结果表明,太阳的重力场通过与太阳内部的扩散和对流过程相耦合影响核反应扩散系统的动力学行为.在太阳中心0~0.38 R ⊙的核反应区内,重力场的非均匀性(△·g)将导致3He核反应扩散系统的非稳定性,失稳后的新状态具有振荡特性.3He的这种性质可以改变7Be和8B太阳中微子的产生率.  相似文献   

2.
研究太阳中心的核反主尖对太阳中微子问题的解释至关重要,也是当前太阳振动测量中最为困难的问题。通过对p-pⅠ核反应链中密度的时间变化研究发现,在从0.0902R⊙到0.1507R⊙的中心区域内,^3He的粒子数密度恰好以5min左右的周期随时间振荡。这类振荡可以引起太阳核能产生的周期变化,从而改变了太阳中微子的产生率。  相似文献   

3.
用非平衡态动力学方法 ,研究了太阳的重力场对其内部核反应扩散系统的影响 ,得到了从太阳中心到 0 38太阳半径的核反应区域内 ,重力场的非均匀性将导致核反应扩散系统的非稳定性 ,失稳后所产生的新状态具有时间振荡特性 ,这种性质可以改变太阳中微子的产生率  相似文献   

4.
用非平衡动力学方法,研究了太阳的重力场对其内部核反应扩散系统的影响,得到了从太阳中心到0.38太阳半径的核反应区域内,重力场的非均匀性将导致核反应扩散系统的非稳定性,失稳后所产生的新状态具有时间振荡特性,这种性质可以改变太阳中微子的产生率。  相似文献   

5.
对流、核反应和太阳内部振荡   总被引:1,自引:0,他引:1  
给出恒星内部对流与核反应耦合的一个动力学模型.借助标准太阳模型,证明了在太阳中心的核反应中,3He的粒子数密度产生和消灭过程均呈振荡状态.在能量产生的峰值区域内,3He的振荡周期大约为5min,代表着总能量产生的振荡特征.太阳内部的这一特性预期可以说明观察到的中微子流的时间变化.  相似文献   

6.
给出恒星内部对流与核反应耦合的一个动力学模型,借助标准太阳模型,证明了在太阳中心的核反应中,^3He的粒子数密度产生和消灭过程均呈振荡状态,在能量产生的峰值区域内,^3He的振荡周期大约为5min,代表着总能量产生的振荡特征,太阳内部的这一特性预期可以说明观察到的中微子流的时间变化。  相似文献   

7.
太阳中心^8B中微子的产生   总被引:3,自引:0,他引:3  
研究了^8B中微子产生过程中存在时间振荡的动力学判据Homestake实验记录的太阳中微子流具有时间周期性,而Super-Kamiokande实验观测的太阳中微子流基本上是恒定的,这一矛盾的合理解释可能是太阳中心中微子的产生率具有长的时间振周期。  相似文献   

8.
研究了重力 温度梯度效应影响下的恒星核反应扩散系统中的涨落,分析了在核反应进行过程中与粒子数密度相关的振荡现象.分析得出:恒星内部存在粒子数密度的振荡现象和一系列涨落波在空间传播,重力 温度梯度效应是驱动振荡的主要原因,这类振荡可以引起恒星核能的产生出现周期性的时间变化.对p—p反应动力学模型的具体分析表明,由于3He的振荡性质,8B和7Be中微子流的产生将随时间变化.  相似文献   

9.
研究了8 B中微子产生过程中存在时间振荡的动力学判据. Hom estake 实验记录的太阳中微子流具有时间周期性,而 Super Kam iokande 实验观测的太阳中微子流基本上是恒定的.这一矛盾的合理解释可能是太阳中心中微子的产生率具有长的时间振荡周期  相似文献   

10.
标准太阳模型预言7Be太阳中微子流强为 (3 4 4± 3 4)SNU ,且不依赖核反应7Be(p ,r) 8B截面测量的不确定性 .假如太阳中微子在它们产生后没有发生任何变化 ,且正在运行的太阳中微子测量实验是正确的 ,那么在SuperKamiokande实验上8B太阳中微子流强约为标准太阳模型预言值的 47 3 % ,CNO中微子流强也是标准太阳模型的一半 .对于7Be太阳中微子 ,当其不一致性不超过 1倍或 3倍标准偏差时 ,在镓探测器上7Be太阳中微子只有标准太阳模型预言值的 19 6%或 5 2 6% .  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
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   

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