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101.
考虑了定义在半无限柱体上的非标准Stokes流体方程的初边值问题,其中在柱体的有限端施加非线性边界条件,在柱体的侧面上满足零边界条件.在初始条件中参数的适当范围内,利用微分不等式技术,得到了Stokes流体方程的二择一结果.在衰减的情况下,证明了"全能量"可以由已知数据项控制. 相似文献
102.
修正传统有效市场假说,重新假设外汇汇率存在扩散和跳跃,并结合CGMY模型,采用傅里叶变换方法,推导出了CGMY模型下欧式外汇期权价格满足的分数阶偏微分方程(FPDE).尽管因分数阶偏导数引发的“全局性”很难处理,仍然推导出CGMY模型下欧式外汇期权的定价公式及其满足的平价公式.同时,引入一个新的缩放参数m来控制指数函数的增长率以克服被积函数衰减引起的计算困难,使其与Lévy密度函数的衰减在速度上达到一个平衡.最后,从数学与金融意义上分析了关键参数变化对欧式外汇期权价格的影响. 相似文献
103.
KIM KyeongHun 《中国科学 数学(英文版)》2012,55(11):2233-2246
In this paper we present an L 2-theory for a class of stochastic partial differential equations driven by Lévy processes.The coefficients of the equations are random functions depending on time and space variables,and no smoothness assumption of the coefficients is assumed. 相似文献
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研究了Knight不确定环境下的Lévy型金融市场.假设标的股票价格服从Lévy过程,借助Lévy-Laplace指数建立了欧式期权的动态定价模型,得到了定价区间,并针对Lévy纯跳过程给出了模型的显示解.最后,利用数值分析方法,研究了Knight不确定性参数对欧式看涨期权定价区间的重要影响. 相似文献
106.
LIZi-Ping LIRui-Jie 《理论物理通讯》2001,36(2):157-162
Based on the canonical action,a generalized canonical first Noether theorem and Poicare-Cartan integralinvariant for a system with a singular high-order Lagrangian are derived.It is worth while to point out that the constraints are invariant under the total variation of canonical variables including time.We can also deduce the result,which differs from the previous work to reuire that the constraints are invariant under the simultaneous variations of canonical variables.A counter example to a conjecture of the Dirac for a system with a singular high-order Lagrangian is given,in which there is no linearization of constraint. 相似文献
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Ahmad Ahmeda Behnam Mahdavi Farhad Zaker Saeid Kaviani Soudabeh Hosseini Mohammad Mahdi Zangeneh Akram Zangeneh Sogand Paydarfar Rohallah Moradi 《应用有机金属化学》2020,34(3):e5433
The therapeutic properties of tin nanoparticles have been proved in recent years. One of their probable effects is anti-anemia. In this study, tin nanoparticles were synthesized and characterized in aqueous medium using Ziziphora clinopodioides Lam leaf aqueous extract as the reducing and stabilizing agent. We also assessed the antihemolytic anemia potential of tin nanoparticles (SnNPs) in an animal model of hemolytic anemia. Tin nanoparticles were characterized using many techniques including Fourier transform-infrared and UV-visible spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectrometry, and field emission-scanning electron microscopy (FE-SEM). FE-SEM images showed a uniform spherical morphology in size of 18.12 nm for the green synthesized nanoparticles. According to XRD analysis, SnNPs crystal size was17.94 nm. SnNPs had low cell viability dose-dependently against human umbilical vein endothelial cell line. in vivo design, induction of hemolytic anemia was done by phenylhydrazine in 40 mice. Tin nanoparticles significantly (p ≤ 0.01) reduced the weight and volume of liver and spleen and the concentration of pro-inflammatory cytokines, and increased the body weight, anti-inflammatory cytokines concentration, total platelet, WBC, neutrophil, lymphocyte, eosinophil, monocyte, and basophil counts, and red blood cell parameters compared to the untreated mice. For the biochemical parameters, SnNPs significantly (p ≤ 0.01) increased the concentrations of GPx, CAT, and SOD in serum, liver, and spleen and decreased the concentration of GR in serum, liver, and spleen, and also erythropoietin, ferritin, and ferrous in serum as compared to the anemic mice. The 2,2-diphenyl-1-picrylhydrazyl test showed similar antioxidant activities for SnNPs and butylated hydroxytoluene. The results demonstrate the excellent antihemolytic anemia, hematoprotective, cytotoxicity, and antioxidant potentials of SnNPs compared to other experimental groups. 相似文献
110.
建立了交替循环和直接循环液相色谱相结合的方法用于制备芳香新塔花中的化学成分.芳香新塔花样品经溶剂提取、柱色谱和中压制备色谱初步分离后得到芳香新塔花的不同馏分.以甲醇-水为流动相,利用双柱交替循环法对组分进行分离,同时,流动相经恒流泵循环输入色谱柱.以馏分Ⅰ和馏分Ⅱ为例,在混合循环模式下分离得到5个化合物.通过核磁共振对其进行鉴定,确定分别为乔松素-7-O-芸香糖苷、白杨素-7-O-芸香糖苷、金合欢素-7-O-芸香糖苷、云杉素和原儿茶酸.实验结果表明,该制备方法分离效率高,节省流动相,是分离天然产物的有效手段. 相似文献