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1.
采用量子力学abinitio从头算,运用Gaussian03软件包中的三种方法结合不同基组优化计算了BeO分子基态(X^1∑^+)的结构,选用二次组态相互作用QCISD(T)方法结合、6-311++G**(3af,3N)基组对BeO分子基态(X^1∑^+)进行了单点能扫描计算;用Murrell-Sorbie函数表示分子解析势能函数,得出了相关系数和力常数,并计算出了BeO分子的光谱数据(ωe、ωeXe、Be、αe、De),结果与实验光谱数据吻合较好。  相似文献   

2.
无穷区间上二阶多点边值问题的多个正解的存在性   总被引:1,自引:0,他引:1  
利用Leggett-Williams不动点定理,得到了无穷区间上二阶多点边值问题{x″(t)+q(t)f(t),x′(t))=0,t∈J+,x(0)=^m-2∑i=1αix(ζi),x^′(∞)=0,3个正解的存在性结果.  相似文献   

3.
为了弄清BCl在金属蚀刻中的机理,了解BCl分子激发态势能函数和稳定性的基本信息是必要的。运用群论及原子分子反应静力学方法,推导出了BCl分子低激发态A^1∏、a^3∏1的电子态及相应的离解极限;使用SAC/SAC—CI方法,6—311++g(d)^**基组对BCl分子低激发态A^1∏、a^3∏1的平衡结构和谐振频率进行了几何优化计算,并对BCl分子低激发态A^1∏、a^3∏1进行了单点能扫描计算,用正规方程组拟合Murrell—Sorbie函数,得到相应电子态的势能函数解析式,利用得到的势能函数计算了相对应的力常数(f2、f3、f4)和光谱数据(Be、αe、ωe、ωe、χe、),数据值分别为:基态BCI(X^1∑^+)的Re=0.1867nm,De=1.4855eV,Be=0.6228cm^-1,αe=0.0060cm^-1,ωe=810.2001cm^-1,ωeχe=4.981cm^-1;激发态BCI(a^3∏1)的Re=0.1726cm,De=6.1151eV,Be=0.6843cm^-1,αe=0.0039cm^-1,ωe=897.8493cm^-1,ωeχe=5.2800cm^-1;激发态BCI(A^1∏)的Re=0.1722nm,De=7.1515eV,Be=0.6799cm^-1,αe=0.0085cm^-1,ωe=784.5359cm^-1,ωeχe=12.88cm^-1.结果与文献数据相符合;在基态的平衡位置处,计算了从基态到A^1∏、a^3∏1态的垂直激发能,其值分别为7.6291eV,10.1023eV.  相似文献   

4.
CN分子基态(X^2∑^+)的结构与分析势能函数   总被引:2,自引:1,他引:1  
利用原子分子反应静力学的有关原理,推导出了CN分子的合理离解极限.采用密度泛函理论的B3LYP方法和二次组态相互作用的QCISD和QCISD(T)等理论方法,在D95(d),6-311G^*和6-311+G^*基组下,对CN分子基态的平衡结构、离解能和谐振频率进行了优化计算,利用QCISD/6-311+G^*对CN分子的基态进行了单点能量扫描,并将扫描结果用正规方程组拟合Murrell-Sorbie势能函数.由拟合得到的势能函数计算与X^2∑^+态相应的光谱常数(Be、αe、ωe和ωeχe),其结果与实验符合得较好.  相似文献   

5.
利用分子反应静力学的原理,确定了^7Li2分子A^1∑^+态的离解极限;利用SAC-CI方法、使用6-311G、6-311++G、6-31IG(3df,3pa)、6-311++G(3df,3pd)、D95(3df,3pd)、D95、D95V、D95V(d,p)、cc-PVTZ和AUG-cc-PVTZ等基组,对^7Li2分子A^1∑^+u态的平衡几何进行了优化计算,且将计算结果与精细的单点能扫描结果进行了比较.分析表明。由单点能扫描获得的平衡核间距应更为合理.同时也得出了AUG-cc-PVTZ基组为最优基组的结论.在0.14—1.5nm范围内对该态进行了单点能扫描,并用最小二乘法拟合出了其解析势能函数.从得到的解析势能函数出发,计算了谊态的力常数(f2、f3和f4)及谐振频率(ωe),进而计算了其他光谱常数(Be,αe和ωeХe),理论值与实验结果一致.同时为便于分析和比较,对基态X^1∑^+g也进行了相应的计算.  相似文献   

6.
通过设立半群的方法,研究了形如:x'(t)=A0x(t)+∑i=1^pAix(t—hi),t≥0的一类时滞方程的解的适定性,其中A0是Banach空间X上解析半群{e^A0t,t≥0}的无穷小生成元,Ai(i=1,2,…,p)均为(γ—A0)^α-相对有界线性算子,其中0〈α〈1,γ〉ω0(A0)为解析半群{e^A0t,t≥0}的增长界。  相似文献   

7.
利用重合度理论,讨论了含有变时滞的一类二阶中立型泛函微分方程:d^2/dt^2[x(t)-kx(t-τ(t))]+∑i=0^m αi(t)f(x(t)),x(t-μi(t)))+∑i=0^m βi(t)g(x(t-γi(t)))=p(t)周期解存在性问题,得到了周期解存在的充分条件.  相似文献   

8.
主要证明了如下几个结果:1.设X=σ∈∑Xσ是∑一仿紧空间,则X是可缩的(具有性质,性质)当且仅当F∈∑〈ω,σ∈FXσ是可缩的(具有B性质,D性质),2.设X=i∈ωXi可数仿紧,,则下面各条等价:(1)X是可缩的具有B性质,D性质);(2)α∈[ω]〈ω,i∈αXi是可缩的(具有B性质,D性质);(3)n∈ω,i〈nXi是可缩的(具有B性质,D性质)。  相似文献   

9.
采用单双取代耦合簇理论CCSD(T)/cc—pVQZ和二次组态相互作用方法QCiSD(T)/cc—pVTZ对BeH+,BeD+和BeT+离子基态(X1∑+)进行几何优化和单点能扫描,计算BeH+,BeD+和BeT+离子的势能曲线.利用所得势能曲线计算出相应的光谱常数(ωc,ωcXc,Bc,αc和Dc)和分子振动能级,并与已有的实验数据进行了比较。  相似文献   

10.
通过函数f(x)=(α+βx)/(1+kx^γ)在[0,+∞]上的单调性,并利用上下极限方法得到了非线性差分方程xn+1=(α+βxn-k)/(1+^k∑i=1x^γn-i+1)正平衡点的全局吸引性,同时还得到正振动解的半循环分布.其中α〉0,0〈β〈1,0〈γ≤1,k∈N,x-k…x0是任意非负实数.  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.
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 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   

15.
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   

16.
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   

17.
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   

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.
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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