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1.
用l分裂屏蔽氢离子模型计算了Ag等离子体在不同温度、密度范围内随光子能量变化的辐射不透明度,探讨了温度、密度对Ag等离子体辐射不透明度的影响,以及不同温度和密度条件下自由-自由、束缚-自由、束缚-束缚这3种跃迁过程对辐射不透明度的贡献.  相似文献   

2.
用SHML理论模型计算了Ar和Kr混合物的不透明度,研究了温度在100~900 eV,密度在0.5~2 g/cm3范围内Ar和Kr混合物平均不透明度随等离子体密度和温度的变化规律.结果显示,平均不透明度增高或降低的现象不仅与混合物有关,而且与等离子体的温度有关.在100~200eV的较低温度下,Ar和Kr混合后的平均不透明度比纯氪低,但在800~900eV的较高温度范围内,Ar和Kr混合后的平均不透明度却比它们为纯元素时出现了增高.不透明度的增高有利于减小杂质离子辐射对聚变反应的破坏.  相似文献   

3.
基于平均原子模型计算了Hg等离子体的不透明度,计算过程包含了电四极跃迁对不透明度的影响,讨论了这种影响对密度的依赖.  相似文献   

4.
用(l)分裂的屏蔽氢不透明度模型计算了惰性元素Kr等离子体随光子能量变化的不透明度,其中束缚-自由跃迁积分、束缚-束缚跃迁积分中的波函数采用了类氢波函数. 探讨了温度为100~600 eV, 密度为0.5~2 g/cm3范围内kr等离子体不透明度随温度和密度的变化规律,以及自由-自由、束缚-自由、束缚-束缚这三种跃迁过程对不透明度的贡献.  相似文献   

5.
本文考虑了各种过程对不透明度的贡献,并把不透明度写成参量形式,利用热力学定律和扩散方程得到了Ⅱ型超新星光极大后光变曲线解析解的普遍表达式。进而讨论了各种不透明度对超新星光变曲线的影响,采用我们的方法比较好地解释了超新星的一些观测特性,并拟合了两颗SNⅡ—L观测光变曲线  相似文献   

6.
在局部热动平衡下,采用改进过的平均原子模型的解析式对Fe、Al等离子体在温度、密度较高时的不透明度进行计算.并考虑到元素序数、温度和密度对不透明度的不同影响,引入了一个经验性的修正因子对束缚-束缚跃迁谱线的线宽进行了修正,修正后的不透明度的计算值更接近实验值.  相似文献   

7.
苗劲松  张胜海  杨华  董冰 《河南科学》2011,29(12):1427-1429
理论上分析了电四极跃迁对激发能态的依赖,基于平均原子模型计算了Al和Au等离子体的不透明度,探讨了内壳层电四极跃迁在不透明度计算中的重要性,数值计算和理论分析相当吻合.  相似文献   

8.
基于不完全信息非合作博弈理论,本文对买方定价不透明销售模式中供应商与中介商的博弈进行了分析,得出了供应商对不透明产品门槛价格设定的贝叶斯均衡解和中介商对不透明产品不透明度设定的策略应对.结论表明,在买方定价不透明销售模式中,在顾客竞价成功的前提下,供应商个数越多,中介商所获得的信息租金越高;但供应商个数增多时,也会加大产品销售的不透明度,导致顾客的报价大幅降低.因此,中介商需要在不透明度大小的设定和自身收益之间进行权衡.  相似文献   

9.
寻人不遇诗是唐诗中一类很有趣味的内容,数量虽然不大,但却颇能透露出唐人写诗的情趣。不遇诗中最有特点的是不遇而有所得的作品,其心有所得的满足感其实是诗人自我人格理想在自然中得到艺术化的折射,在艺术上具有以实写虚的特点。  相似文献   

10.
随机调制单极化有源假目标的极化鉴别研究   总被引:9,自引:0,他引:9  
以分时极化测量雷达为例,分析了随机转发的单极化有源假目标的极化特性;提取了目标和单极化有源假目标的一个稳健的特征量——散射矩阵的归一化行列式值;利用单极化有源假目标和雷达目标极化特性的差异,提出了一种基于散射矩阵互易性和归一化行列式值的真假目标极化鉴别方法.对典型雷达目标和单极化有源假目标的目标鉴别仿真实验表明,该方法可以有效鉴别单极化随机调制的有源假目标和单极化噪声干扰形成的假目标.  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.
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   

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