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1.
在文献[1]、[3]、[4]、[5]的基础上在线性模型的框架下,我们利用微分形式的上同调理论很简捷地得到了相对论和非相对论的动力学方程并探讨了最小作用量原理是不比先验地提出来的。  相似文献   

2.
本文测量了xLi_2O·0.15Ta__2O_5·(0.85-x)GeO_2三元系统玻璃的GeK边和TaL边的EXAFS谱。利用计算机进行曲线拟合得出了玻璃中[CeO_4]四面体和[KeO_6]八面体的百分含量,所得结果表明:该三元系统存在着“锗反常”现象。随着Li_2O的加入,玻璃中[GeO_4]部分转变为[GeO_6]。当 Li_2O含量为25mol%时,[GeO_6]含量达到极大值.即[GeO_6]为25%,当继续加入Li_2O时非桥氧的[GeO_4]增加,而下稳定的[GeO_6]减少。钽L边的EXAFS研究表明:钽在玻璃中主要以[GeO_6]八面体存在,T-O键长为1.98A·左右。同时探讨了玻璃的结构模型。  相似文献   

3.
0 IntroductionIntheprocessofR&Ditem ,thereisusuallycompetition .ManyfirmswanttoinvestR&Dtoobtainapatent.Lury[1 ] gaveanequilibriuminvestmentundertheconditionofone timeinvestmentandcontinuousinvestmentwhenthepayoffwasafixedprize.Ref.[2 ]analyzedtheeffectofinformationsharinginR&D .TherearemanyliteraturesaboutanalysisofR&DlevelswhenfirmscompeteinoutputmarketafterR&Dsucceeds[3 ,4] .Additionally ,todecideinvestmentlevel,therearemanyliteraturesaboutR&Ditem’spricing .MondherBellalah[5] ,K .…  相似文献   

4.
在文[9]的基础上,给出了不同偏好关系的映射模型。这些模型验证了文[9]中建立的偏好关系的对偶理论以及各蕴涵式的正确性。  相似文献   

5.
本文证明了由Bhansaai[1]提出的偏逆自相关函数估计的强收敛速度和渐近正态性。并利用这些结果证明了[1]提出的一种模型定价法的强相容性。  相似文献   

6.
Ramsauser模型[1]是计算中子全截面的经验模型,根据Ramsauser模型计算27-Co-59,41-Nb-93,83-Bi-209,五个核的中子全截面.APMN[2]程序中的球型光学模型是理论模型,通过它再次计算27-Co-59的中子全截面,然后两种模型进行比较,并对两种模型的计算结果做出分析结果.  相似文献   

7.
采用改进的Al-Fe-Ferron逐时络合比色法定量研究了HPAFC的化合形态分布与转化,结合酸解聚实验和酸反滴定实验结果,描述了其形态分布特征.结果表明HPAFC的化合形态主要决定于n(Al):n(Fe)比值、碱度值和陈化时间,并且可划分成三个主要化合形态分布区,即单体和二聚体[Al+Fe]a、中间多核羟基络合物[Al+Fe]b和溶胶态[Al+Fe]c,而且它们之间可相互直接转化.当n(Al):n(Fe)>5:5时,[A1+Fe]a和[A1+Fe]b为主要化合形态;除了[A1+Fe]b之外,[Al+Fe]a和[Al+Fe]c随n(Al):n(Fe)减小而增大.最后提出了HPAFC的化合形态分布与转化模型.  相似文献   

8.
页岩介质中放射性核素迁移的实验研究及其数学模型   总被引:4,自引:0,他引:4  
在自行设计的实验装置中进行了放射性核素[3]I在页岩介质中的扩散、渗透-弥散的实验,采用渗透法及扩散法获得了实验曲线并计算出弥散系数、阻滞系数、孔隙度等参数。实验表明[3]I在页岩介质中为弱吸附核素,其阻滞系数较小,在此实验基础上建立了放射性核素[3]I在页岩介质中的一维迁移物理模型及数学模型,结果表明[3]I随地下水迁移得比较慢,因此页岩对[3]I的迁移能起到一定的阻滞作用。  相似文献   

9.
在文献[5]、[6]的基础上,本文运用泛结构模块网络建模方法,建立跨批使用缓冲区串行生产线最早开工时刻状态变量的Kalman-(A,F,B,C)模型。  相似文献   

10.
采用共存理论、动力学分析和实验验证的方法,研究转炉冶炼超低碳钢吹炼末期炉渣成分对终点[ C]含量的影响规律,建立1853~1973 K时终点[ C]与炉渣成分和温度的回归模型. 结果表明:FeO活度受温度影响较小,主要受炉渣成分的影响;脱碳动力学条件主要受炉渣成分和温度的影响. 炉渣碱度增加,终点[ C]含量升高;渣中FeO含量增加,终点[ C]含量迅速降低,渣中FeO质量分数应控制在12. 0% ~18. 0%之间;渣中MgO质量分数在7. 0% ~13. 0%范围内逐渐增加,钢液中[ C]质量分数增加值不足0. 01%;随着温度的增加,钢液中[ C]含量降低. 回归模型对冶炼超低碳钢的转炉终点[ C]含量的预判平均误差率为± 15. 25%,[ C]含量误差在± 0. 01%以内的炉次占69. 19%.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

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   

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