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1.
借用密度泛函方法并结合局域密度近似和Bethe ansatz精确解结果,研究了玻色费米混合物及旋量玻色气体在束缚于一维简谐外势下时各分量的混合与相分离。结果表明,玻色费米混合物会随着玻色-玻色、玻色-费米原子间排斥相互作用的增强,出现费米子被排斥在势阱中心之外的玻色费米部分相分离现象,当排斥相互作用趋于无限强时,玻色费米混合物的基态能量和总密度与所有原子都费米化的情况相一致;自旋-1玻色气体在密度-密度排斥和反铁磁自旋交换相互作用下会出现配对玻色子和极化玻色子相分离的现象,在强作用下,各自的密度分布曲线分别趋近于玻色-玻色对的TG气体和标量玻色TG气体,而中心密度随相互作用强度的变化呈非单调性。  相似文献   

2.
本文采用泛函积分方法研究了高温超导中玻色-费米子模型的长波激发.推导了能隙方程和激发谱方程,并且计算了在长波近似下费米场的玻色能谱,得到了简并和非简并激发模.  相似文献   

3.
山西大学量子光学与光量子器件国家重点实验室张靖教授研究小组于2007年7月7日成功实现了铷原子的玻色爱因斯坦凝聚(BEC)。实验结果显示,冷原子云在温度降低到约为500nK时开始发生相变,经过进一步蒸发冷却,最终得到了约为6×10^4个原子的纯净BEC。目前该小组正将铷原子和费米原子咏同时装入磁阱中,蒸发冷却铷原子来协同冷却钾原子,最终同时实现玻色气体玻色爱因斯坦凝聚和费米气体量子简并。  相似文献   

4.
在连续化极限情况下把量子一维格点扩展Hubbard模型变换为连续的费米场.进而采用玻色化方法得到模型的玻色场形式.比较玻色化扩展Hubbard模型和玻色化XXZ链,导出了两者的等价性.利用XXI链模型的严格解和玻色化解的关系,计算了格点扩展Hubbard模型的关联函数,给出了格点扩展Hubbard模型的相图.当模型的相互作用发生变化时,扩展Hubbard模型会历经四个不同的相,并在相区分界线处存在不同类型的相变.最后,提出了扩展Hubbard模型相图中电荷密度波和自旋密度波相边界漂移的合理解释.  相似文献   

5.
本文分别给出了非相对论和相对论情况下玻色统计和费米统计的能量,动量以及速率分布函数,结果发现在考虑相对论情况时,玻色统计和费米统计的能量和动量分布的大体形状是不变的,但速率分布就有了较大的变化.  相似文献   

6.
采用Jordan-W igner变换和玻色化方法研究外场中的自旋-1/2XY模型.由于外磁场的引入,该模型的玻色化过程受到影响,首先讨论该模型在无磁场情况下的哈密顿,随后对磁场引入的扰动项做了单独地玻色化;并在阿贝尔玻色化方案下对玻色场算符做了重新定义,从而解决了由于扰动所带来的协变问题,给出了各关联函数的表达式;最后简单讨论在处理此类模型时,玻色化方法较之其他方法的优长.  相似文献   

7.
扩展Hubbard模型的玻色化   总被引:1,自引:1,他引:0  
在连续化极限情况下把量子一维格点扩展Hubbard模型变换为连续的费米场.应用玻色化方法和sine-Gordon模型的相图讨论了量子一维扩展Hubbard模型的临界现象.当模型的相互作用发生变化时,扩展Hubbard模型会历经四个不同的相,并在相区分界线处存在不同类型的相变.和以前扩展Hubbard模型相图比较,发现用玻色化方法得到的相图给出模型描述更详尽.  相似文献   

8.
摘要:根据费米型质子PB^ 1、中子nF^0、电子e^-1的超对称性伴子玻色型PB^ 1nB^0、-↑Ue^-,1↑B粒子,讨论反氢原子的结构,计算费米型氘核PF^ 1nF^0和玻色型氘核PB^ 1nB^0结构函数的矩,结果发现反氢原子的结构与目前观测到费米型反氢原子不同,氘核PB^ 1nB^0结构函数的矩的理论值与实验数据较好相符,PB^ 1nB^0结构函数的矩的计算结果比PB^ 1nF^0要大,增大的值是由于费米型中性矢量反轻子-↑l0F,T结构函数的贡献所致。  相似文献   

9.
根据费米型质子P+1F、中子n0F、电子e-1的超对称性伴子玻色型+1B、0B、U-1e,B粒子,讨论反氢原子的结构,计算费米型氘核P+1Fn0F和玻色型氘核P+1Bn0B结构函数的矩,结果发现反氢原子的结构与目前观测到费米型反氢原子不同,氘核P+1Fn0F结构函数的矩的理论值与实验数据较好相符,P+1Bn0B结构函数的矩的计算结果比P+1Fn0F要大,增大的值是由于费米型中性矢量反轻子0F,T结构函数的贡献所致.  相似文献   

10.
人们通过对费米原子量子气体施加变化的磁场产生超冷分子,由此开创了制备新型超流体和分子玻色、爱因斯坦凝聚体的美好前景。  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.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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