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811.
812.
本文在假定标的资产模型依赖时间参数(即无风险利率,标的资产的期望收益率,波动率及红利率),利用已建立的亚式期权定价模型,讨论了上限型期权、抵付型期权、双向型期权等,得到相应的期权定价解析公式. 相似文献
813.
通过7-芳亚甲基-6,7-二氢中氮茚-8(5H)-酮与甲亚胺叶立德(经苊醌或靛红与肌氨酸反应原位生成)进行的l,3-偶极环加成反应,合成了具有良好产率的新的1’-甲基-4’-芳基-5",6"-二氢-2H,8"H-二螺[苊烯-1,2’-吡咯烷-3’,7"-中氮茚]-2,8"-二酮类化合物和1’-甲基-4’-芳基-5",6"-二氢-1H,8"H-二螺[吲哚-3,2’-吡咯烷-3’,7"-中氮茚]-2,8"-二酮类化合物.采用NMR,IR,质谱,元素分析以及X射线单晶衍射等多种谱学技术对产物进行了结构表征. 相似文献
814.
A necessary and sufficient condition is obtained for the existence of symmetric positive solutions to higher-order nonlinear boundary value problems. The uniqueness, an iterative sequence and an error estimation for symmetric positive solutions are also discussed. Moreover, we give an example to illustrate the applicability of our results. Our analysis mainly relies on the monotone iterative technique. 相似文献
815.
在苯类化合物的凯库勒结构的研究中引入了反强迫数和反凯库勒数.通过分析矩形和斜带模型苯类化合物的分子图的结构,证明了具有k行l列的矩形R[k,l]和斜带模型Z[k,l]的反凯库勒数是2,R[k,l]的反强迫数是l,Z[k,l]的反强迫数不超过[(l+1)/2],其中[x]表示不超过x的最大整数. 相似文献
816.
Jianting Tang Xiaomiao Chen Yu Liu Wei Gong Zhenshan Peng Tiejun Cai Liangwen Jin Qian Deng 《Journal of Physics and Chemistry of Solids》2012,73(2):198-203
Mesoporous anatase doped with various amounts of Eu were synthesized via a sol-gel route using Pluronic P123 as template. The XRD and TEM results show that Eu doping favors the formation of anatase with smaller crystal size. The photocatalytic activity of the mesoporous anatase was tested in photocatalytic elimination of gaseous methanol. The photocatalysts exhibited higher activity than that of the commercial photocatalyst (Degussa, P25) under either ultraviolet or visible light irradiation. The superior activity of the mesoporous anatase may be attributed to the synergic effects of the surface area, crystal size and doped Eu species. 相似文献
817.
Guanfan Chen Chenzhong Cao Bin Sheng Yun Zhu Zhenxing Wu Xiangsi Wu 《Journal of Physical Organic Chemistry》2012,25(10):828-834
The 13C nuclear magnetic resonance (NMR) chemical shifts δc of bridge group carbons (C‐β, C‐α, and C═N) were measured in this work for a wide set of substituted cinnamyl anilines p‐XC6H4CH═CHCH═NC6H4Y‐p (X = NO2, Cl, H, Me, MeO, or NMe2; Y = NO2, CN, CO2Et, Cl, F, H, Me, MeO, or NMe2) and were used to study the substituent effect. In the study on 13C NMR chemical shifts of the titled compounds with single substituent changed, for every bridge carbon δc, the effect of cinnamyl substituent X is opposite to that of aniline substituent Y. That is, the action of the same substituent on different aromatic rings is different from the 13C NMR chemical shifts, and for C‐β, C‐α, and C═N, the choice of correlation equation depends on the ratio ρF(Y)/ρR(Y). When the ratio ρF(Y)/ρR(Y) is close to 1, the chemical shifts of bridge carbons can be well correlated with the single‐parameter equation; otherwise, it is better to adopt the dual‐parameter equation for correlation, and the further the values of ρF(Y)/ρR(Y) stray from 1, the more suitable the corresponding δc values are to be correlated with the dual‐parameter equation. In the study on δc of model compounds with simultaneous variations of substituents X and Y, for δc(C═N), a multi‐parameter correlation equation is obtained, and the substituent cross‐interaction item Δσ2 is suitable to scale the interaction between substituents; however, for δc(C‐α and C‐β), the substituent cross‐interaction item Δσ2 is perhaps too small to be observed. The multi‐parameter correlation equations can be recommended to predict well the corresponding δc values of disubstituted cinnamyl anilines. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
818.
Suppose that g(f) are bi-parameter Littlewood-Paley square functions which were introduced by H. Martikainen. It is known that the boundedness and the boundedness of g(f) have been proved by H. Martikainen and by Z. Li and Q. Xue, respectively. In this paper, we apply the vector-valued theory, the atomic decomposition of product Hardy spaces, and Journe's covering lemma to show that g(f) are bounded from to with p smaller than 1. 相似文献
819.
The correlations between the pressure sensitivity and the fragility/glass transition temperature have been addressed in various bulk metallic glasses in the present work. The results demonstrate that the pressure sensitivity of bulk metallic glasses is closely related to both the fragility index (m) and the glass transition temperature (Tg). The physical origin of the correlations has been discussed from their disordered structure, which is determined by the glass transition behavior and the glass transition temperature. 相似文献
820.
考虑信用风险模型的破产问题,研究Gerber-Shiu贴现罚函数,通过引进辅助模型,运用概率论的分析方法得到了其所满足的积分方程.相应地可以得到该模型下的破产概率、破产时刻前赢余和破产时刻赤字的联合分布及其边际分布,进一步完善了YangHailiang发表的相关问题的结果. 相似文献