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1.
通过引入有限维交换结合代数的σ_自同态映射,研究了σ_半单代数和σ_幂零代数的结构。利用σ_幂零元、σ_幂等元、σ_理想和σ_子代数的直积,我们证明了有限维交换结合σ_半单代数的结构定理的存在性与唯一性。  相似文献   

2.
设Γ_1为对角线元素按减序排列的非负对角形矩阵,U_1是酉矩阵,i=1,2,…,m,则有当A_1,A_2.…,A_m为半正定Hermite矩阵时,有其中Γ_1=diag(σ_1(A_1),σ_2(A_i).……σ.(A_i)).i=1,2.…,m。  相似文献   

3.
J.G.Thompson在1987年提出了如下公开问题:Thompson猜想设G_1,G_2是同阶型有限群,且G_1可解,则G_2可解.Thompson猜想是一个相当困难的问题.本文初步研究了这个问题,得到如下:定理5设G_1是σ-sylow塔群,且G_1与G_2同阶型,则G_2是σ-Sylow塔群.推论6设G_1是超可解群,且G_1与G_2同阶型.则G_2是Sylow塔群,因而G_2是可解群.定理7设G_1是幂零群,且G_1与G_2同阶型,则G_2是幂零群.  相似文献   

4.
对W6Mo5Cr4V2(M2)高速钢模具材料及其它常用模具钢的各种热处理状态的压缩性能进行了研究。研究表明压缩试验能充分显示高硬度模具材料的强度与塑性,高速钢的抗压屈服应力σ_(sc)明显高于其它常用模具钢,达500MPa以上,基于力学状态的分析,证实σ_(sc)与洛氏硬度HRC之间存在良好的线性关系.并指出决定σ_(sc)的主要因素是马氏体组织的强度与碳化物的性质、状态。  相似文献   

5.
讨论了题示化合物在紫外可见光谱中的取代基效应,得到γ_1(1/λ_1)与|σ_p|相关性良好的线性关系。另外,通过对该类化合物部花菁稳定性的研究表明,8′-硝基对开环式的稳定性起着重要的作用。  相似文献   

6.
本文对横力弯曲梁在考虑σ_y应力分量时的塑性铰位置进行探讨。从三个方面分析:1。从理论上分析了σ_y对弹性阶段的中性层位置没产生影响。2.从理论上分析了考虑σ_y的Mis-es屈服准则后,塑性铰上移了一位置,从而提高了梁的极限承载能力。3.用二维弹塑性有限元进行实例计算,得出了塑性铰上移及极限承载能力提高的结果.  相似文献   

7.
研究传热规律为Q∞△时卡诺制冷机的(εR)_(max)导出这时的制冷系数ε_m、制冷率R_m和熵产生率σ_m,并作了有意义的讨论,进一步阐明了参数(εR)_(max)的重要意义.  相似文献   

8.
应用巨正则系综统计法处理电极/溶液界面溶剂化层(内层)偶极取向分布,导出联系分子性质的内层微分电容(C_1(σ))统计表达式,并以汞/甲醇溶液体系为例验证结果.理论表明,C_1与溶剂化层总偶极涨落存在确定关系。  相似文献   

9.
本文给出了图的σ-多项式系数的新上界,设σ(G)为G的σ-多项式, 为G的补图的边导出子图,P_m为长为m的路,本文证明了:若连通,且等式成立当且仅当或.这一结果推广了Ko-rfhage定理。  相似文献   

10.
证明了N参数右连续强增加σ-域族的(ORT)性质等价于(STR)性质,对于具有(PIV)性质的离散N参数σ-增域族,必存在单参数σ-增域族和关于它的停时族(T_z)z∈N ̄N,使  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.
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   

15.
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   

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.
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   

19.
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   

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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