双比例延迟微分方程改进的单支θ-方法的H_α-稳定性

In[13],the author constructes the modified Runge-Kutta method and proves that the modified Runge-Kutta method preserves the order of accuracy of the original one.As a result,it is obtained that theθ-method with 1/2θ1is asymptotically stable.The modified one-legθ-method is a specific form of the modified Runge-Kutta method.This paper deals with H_α-stability for the modified one-legθ-method for system of pantograph equation with two delays.It is proved that the modified one-legθ-method with 0θ≤1 is H_α-stable.Some experiments are given.     

解一类二阶延迟常微分方程连续RKN方法的P-稳定性

In this paper, we study the P-stability of the continuous Runge-Kutta Nystroem method for solving the delayed second order differential equation that does not depend on y′. A general theorem is presented which can be used to obtain complete characterizations of the P-stability regions of these continuous RungeKutta- Nystroem methods. We use the condition to two given RKN methods.     

时滞抛物型方程的高精度精细积分法

对一类时滞抛物型方程初边值问题,提出了关于空间步长是四阶精度的高精度无条件稳定的精细积分法.数值算例表明,本文提出的精细积分法具有很高的精度,因而是一种有效的数值方法.     

特异性检测珍珠龙胆石斑鱼虹彩病毒病的核酸适配体的筛选与鉴定

石斑鱼虹彩病毒是一种核质DNA病毒,不仅给海水养殖造成巨大的经济损失,而且严重威胁全球生物多样性。为了进一步阐明石斑鱼虹彩病毒侵染致病的分子机理,同时为石斑鱼虹彩病毒病的预防、诊断和治疗提供新的理论依据,本研究以珍珠龙胆石斑鱼虹彩病毒(SGIV-Gx)感染的宿主细胞为靶标,采用指数富集配体系统进化技术(SELEX)筛选获得4条核酸适配体(LYGV1、 LYGV2、 LYGV3、 LYGV4),并对核酸适配体的性质进行了系统的分析研究。各条核酸适配体识别SGIV-Gx病毒感染的宿主细胞具有高特异性和高亲和性,筛选的核酸适配体无毒副作用,而且核酸适配体LYGV3具有一定的抗病毒效果。对核酸适配体的靶标性质进行了分析,结果表明,核酸适配体(LYGV1、 LYGV2、 LYGV3、 LYGV4)的靶标可能是细胞膜蛋白或膜蛋白相关成分。其中,核酸适配体LYGV1的靶位点在SGIV-Gx病毒感染细胞2 h后出现在宿主细胞表面,核酸适配体LYGV2、LYGV3和LYGV4的靶位点的出现时间分别为病毒感染细胞后的4、8和6 h。     

PVP存在下液液界面生长法制备硒纳米线(英)

0IntroductionSelenium(Se)iswellknownforitsphotoelectri鄄calandsemiconductorpropertiesandhasbeensuc鄄cessfullyusedinsolarcells,rectifiers,photographicexposuremetersandxerography[1].Itcouldbeexpect鄄edthattheuniquestructureandthequalityofone鄄di鄄mensional(     

二阶延迟微分方程θ-方法的TH-稳定性

This paper is concerned with the TH-stability of second order delay differential equation. A sufficient condition such that the system is asymptotically stable is derived. Furthermore, a sufficient condition is obtained for the hnear θ-method to be TH-stable. Finally, the plot of stability region for the particular case is presented.     

比例延迟微分方程组具有刚性精度Runge-Kutta方法的稳定性分析

该文研究比例延迟微分方程组具有刚性精度变步长Runge-Kutta方法的渐近稳定性，给出了一类普遍意义下的变步长格式。证明当且仅当其稳定函数在无穷远点处的模小于1时，变步长Runge-Kutta方法渐近稳定。     

陵水暗罗有效成分的研究 Ⅰ.天然含锌化合物暗罗素的分离及结构

我们从海南岛产的药用植物陵水暗罗中分得一种含锌化合物(得量0.0008%),经鉴定为2-巯基吡啶-Ⅳ-氧化物锌盐,并经合成确证。该化合物对鼠疟具有抗疟原虫的作用。这种金属化合物存在于高等植物中,可能是一种植物他感物质(allelopathy)。因此对植物生理与植物生化必然有其重要意义。     

线性随机比例方程的渐近均方稳定性

本文目的是研究线性随机比例方程解析解和数值方法（连续θ方法）的渐近均方稳定性．给出了解析解和数值方法渐近均方稳定的条件．     

解对流扩散方程的子域精细积分AGEI方法

Based on subdomain precise integration method, a class of two-levelimplicit schemes containing parameter a＞0 for the initial-boundary value prob-lem of convection-diffusion equation are presented. Their local truncation errorsare O(a△t+△t2+△x2). The implicit schemes are unconditionally stable for all a＞0. Then on the basis of the implicit schemes, an alternating group explicit iter-ative (AGEI) method is proposed, and convergence of the iterative process isproved. Because the whole calculation process is explicit, so the AGEI method isvery suitable to parallel arithmetic. Numerical example shows that the AGEImethod has high accuracy and good practicability.