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1.
用因子分析方法获悉取代苯衍生物和分子的路径差指数ΔPi之间具有明显的正相关性,通过回归分析得到它们之间的线性方程为:Δ(ΔfHm(BZDs,g))=a ∑biΔPi=cS.其中,Δ(ΔfHm(BZDs,g))为取代苯衍生物的标准生成焓ΔfHm(BZDs,g)和苯的标准生成焓ΔfHm(BZ,g)之差,ΔPi为路径差指数,即为即代苯衍生物的路径指数与苯的路径指数之差,S为障碍点数,c为相互作用度量,复相关系数R≥0.9960,预测值与文献值吻合较好。  相似文献   

2.
基于多体展式方法所导出的NiH2(3Δg)解析势能函数,用准经典的Monte-Carlo轨迹法对Ni(3F4)+H2(X1Σ+g,v=j=0)的分子反应动力学过程进行了计算.结果表明此反应的主产物为交换反应Ni(3F4)+H2(X1Σ+g,v=j=0)→NiH(X2Σ+,v′,j′)+H(2Sg)的NiH(X2Σ+,v′,j′),没有发现NiH2(3Δg)络合物,从反应截面σr与相对平动能Et的关系发现该反应为有阈能反应,阈能值为33.87 kJ/mol.同时,由于Ni的质量比氢的大,发生的是直接碰撞,产物散射角分布是向前的.  相似文献   

3.
研究了以下2类抽象发展方程解的指数衰减性.其中一类为非线性波方程utt-Δu+a∫t0g(t-τ)Δu(τ)dτ+but=u|u|p-2,另一类则为带线性记忆的双曲型方程utt+αut-k(0)Δu-∫+∞0k’(s)Δu(t-s)ds+u|u|p-2=0.利用已有的相关定理,通过构造合适的Lyaponov函数,借用一定的计算技巧从而得到以上方程解的指数衰减性结论.该结论在光学、流体力学、通信等自然科学领域具有非常重要的实际意义.  相似文献   

4.
图G的一个点染色称为单射染色,如果任何两个有公共邻点的顶点染不同的颜色.一个图G称为单射k-可选择的,如果对于顶点V(G)的任何一个大小为k的允许颜色列表L,都存在一个单射染色φ,使得对于v∈V(G),有φ(v)∈L(v).使得G为单射k-可选择的最小k,称为G的列表单射染色数,记作χ_i~l(G).设G是最大度为Δ,围长为g的可嵌入到欧拉示性数χ(Σ)≥0的曲面Σ的一个图.证明了若Δ≥7且g≥6,则χ_i~l(G)≤Δ+3.  相似文献   

5.
关于二阶线性递归序列的一些恒等式   总被引:1,自引:0,他引:1  
设ωn+2=Aωn+2-Bωn(B≠0) (n=0,±1,±2,…),我们完全确定了何时有恒等式ωpn+r=nΣk=0(nR)i n-kskωqk+r (n∈N={0,1,2…}).设u0=0,u1=1,且u+2=Aun+1-Bun(n=0,±1,±2,…),对l,m∈N及函数fN→{k∈Zωk≠0},我们证明了关于l,m对称的恒等式1-1Σk=0Bf(k)uf(k+m)-f(k)ωf(k)ωf(k+m)=m-1Σk=0Bf(k)uf(k+l)-f(k)ωf(k)ωf(k+l)它可用于计算无穷级数+∞Σk=0Bf(k)uf(k+m)-f(k)/(ωf(k)ωf(k+m).本文的结果推广了南献[1]、[2]、[3]、[7]、[8]中相关的工作.  相似文献   

6.
原子特征参数 (δ′i)被定义为 :δ′i =Zi·Xpi2 · (ni- 1) - 1.由δ′i 建构无机分子的连接性指数 ( mL) ,其中 :0 L =Σ(δi′) 0 .5,1L =Σ(δi′·δj′) 0 .5.( 0 L) 2 与 33种过渡元素卤化物的ΔfH 的 R 为 0 .9692 ,( 1L) 0 .5与 2 0种碱金属卤化物的ln( 1/ U)的R 为 0 .994 8,均优于文献方法  相似文献   

7.
在推广的手征SU(3)夸克模型下,研究了带有一个奇异夸克的双重子态Σ*Δ(ST=052)和Σ*Δ(ST=312)的结构.结果表明,尽管手征SU(3)夸克模型和推广手征SU(3)夸克模型短程力的机制完全不同,但两种模型下给出的定性结果是一样的,即这两个双重子态都是束缚态,能量在Σ*Δ道之下却在ΛπΔ道之上.在推广手征SU(3)夸克模型下,Σ*Δ(ST=312)态的结合能比Σ*Δ(ST=052)态的结合能大.  相似文献   

8.
使用SAC/SAC-CI方法,利用D95++**、6-311++g**以及cc-PVTZ等基组,对HD分子的基态(X1Σ+g)、第二激发态(B1Σ+u)和第三激发态(C1Πu)的平衡结构和谐振频率进行了优化计算.通过对3个基组的计算结果的比较,得出了cc-PVTZ基组为三个基组中的最优基组的结论;使用cc-PVTZ基组,利用SAC的GSUM(Group Sum of Operators)方法对基态(X1Σ+g)、SAC-CI的GSUM方法对激发态(B1Σ+u)和(C1Πu)进行单点能扫描计算,用正规方程组拟合Murrell-Sorbie函数,得到了相应电子态的完整势能函数;从得到的势能函数计算了与基态(X1Σ+g)、第二激发态(B1Σ+u)和第三激发态(C1Πu)相对应的光谱常数(Be, αe, ωe 和ωeχe),结果与实验数据基本吻合.  相似文献   

9.
设Σ=(G,σ)是直径为2和3连通的简单符号图,G是Σ的基础图.若Σ扭转等价Δ_2-图或Δ_3-图,则Σ的Betti亏数ξ(Σ)=2,否则Σ是上可嵌入的,即ξ(Σ)≤1.  相似文献   

10.
O4 分子一直被认为是一种潜在的新型高能密度材料 (HEDM)和推进剂 .运用线性回归法研究了O2 分子或离子中O—O键的键长、键级与键能之间的关系 ,得到了相应的线性回归方程 :EO—O=2 0 98.8- 13.0LO—O,γ =- 0 .982 4;EO—O=139.2 2 12 5 8.35lgPO—O,γ =0 .9932 ;其中EO—O表示O—O键能 (kJ/mol) ,PO—O表示O—O键级 ,LO—O则表示O—O键长 (pm) .利用回归方程估算了O3 、O3 、O3 -、O4 的O—O键能 ,讨论了O2 双聚形成O4 即2O2 (g)O4 (g)的热效应 (ΔfHm ) .计算结果表明 ,ΔfHm ≥ - 3.3kJ/mol,说明此反应在标准状况下 ,O4 分子很容易分解形成 2个分离的O2 分子  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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