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(Ⅱ)方法的应用* 《四川理工学院学报(自然科学版)》1999,12(2):0
采用本文第(Ⅰ)报提出的计算多孔催化剂有效因子的方法,针对三种不同形状的催化剂颗粒,对幂函数型动力学方程和双曲动力学方程进行了大量的计算,采用改进的一点配置法所得得计算结果与正交配置解符合。改进的一点配置法的优点是使用简便,计算快速。采用改进的一点配置法还可以计算催化剂颗粒“死区”半径。并且计算结果合理。 相似文献
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提出了一种新的墓于兴趣挖掘的机会网络内容分发策略(Interest Mining Based Scheme,IMBS),通过贝叶斯理论分析节点的兴趣以及节点墓于兴趣的相遇频率,挖掘移动节点随机运动背后所蕴含的人类社交特征和情感特征此外,IMBS采用发布/订阅机制,收集节点的订阅信息,以获取消息在整个网络中的需求量在转发消息的时候,IMBS把消息的需求总量和节点的情感特征以及社交特征结合起来选择下一跳节点仿真实验及算法复杂度分析表明,在不提高算法复杂度的情况下,IMBS可显著减少消息的传输延时和网络开销,并提高消息传输的成功率 相似文献
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一类二阶微分方程的复振荡 总被引:1,自引:1,他引:0
研究了一类二阶线性微分方程f″+A1e^azf'+(A0e^bz+A2e^cz)f=F(z)的复振荡性质,在假定Aj(z)(j=0,1,2)的级小于1,F(z)的级为有限时,证明了方程的解至多除去一个例外,其余解均有无穷增长级和零点收敛指数,且超级为1 相似文献
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基于量子力学的基本假设,对 Zhang 和 Huang 提出的股票市场量子模型进行了改进,构建新的股票市场的哈密顿函数.通过求解相应的薛定谔方程,得到描述股票收益率的波函数.从理论上验证了在中国股票市场上,股票的价格受到市场信息的影响,因利好信息而升高,因不利信息而下降 相似文献
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运用Nevanlinna值分布的理论和方法,研究了微分方程f(k)+Ak-1f(k-1)+…+A1f’+A0f=0(k≥2)解的增长性,其中Aj(j=0,1,…,k-1)是亚纯函数,通过给定Aj的不同条件,证明了齐次线性微分方程的任一非零解均为无穷级. 相似文献
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ZENG ChangJun~ YE Qing~ & FANG ShengGuo~* College of Animal Science Technology Sichuan Agricultural University Ya’an China The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education State Conservation Center for Gene Resources of Endangered Wildlife College of Life Sciences Zhejiang University Hangzhou 《科学通报(英文版)》2011,56(24):2576-2579
The Chinese alligator, Alligator sinensis, is a critically endangered species. A conservation project of gene resources for an endangered species first involves the preservation of organs, tissues, gametes, genomic DNA libraries and cell lines. The present study is the first to establish and cryopreserve cell lines of liver, heart and muscle tissues from the Chinese alligator. The study revealed that there was a large discrepancy in cell migration time in primary cultures among liver (11-12 d), heart (13-14 d) and muscle (17-18 d) tissue pieces. The differences in time in primary cell culture suggested that it was relatively easy to build visceral-derived cell lines for reptiles. Biological analysis showed that the population doubling time for thawed cells was approxi- mately 36 h. Karyotyping revealed that the frequency of Chinese alligator cells showing chromosome number as 2n=32 was 88.6%-93.4%. Chinese alligator cell lines established here provide a vital resource for research and are likely to be useful for protection of this rare and critically endangered species. Furthermore, the establishment of these methods may supply technical and theoretical support for preserving genetic resources at the cellular level for other reptile species. 相似文献
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Nowadays,thedevelopmentandapplicationofsuperconductionisbecomingmoreandmoreimpor tantinmanyareas .Duringtheworkingprocessofsu perconductor,somefactors ,forinstance ,deforma tion ,friction ,andmagneticvortex ,canresultinin stantaneousandrandomheatimpulsion ,andmakeitover heatedtothecriticaltemperatureanddeviatefromthenormaloperationcondition .Undersomeex tremeconditions ,thesuperconductorcannotgobacktothenormalstateevenifremovingthetransientheat load ,thusverysevereandunexpectableconse quencema… 相似文献
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LI Pengyun WANG Liwei WU Beili SHU Cuiling NIE Aihua SHEN Beifen LI Song * RAO Zihe * 《自然科学进展(英文版)》2003,13(10)
Thetherapyofnerveinjuryandneurode generativediseasessuchasAlzheimer’sdiseaseandParkinson’sdiseaseisadifficultprojectforscientiststosurmount.Manydrugsandtherapeuticapproacheshavebeenusedtotreatthesediseases ,buttheresultisunsatisfactory[1] .Inrecent years ,neurotrophinsincludingnervegrowthfactor (NGF) ,neurotrophin3(NT3) ,neurotrophin 4 / 5 (NT4 / 5 )andbrain de rivedneurotrophicfactor (BDNF)werestudiedex tensivelyandfoundtoaffectthesurvival,growth ,and/ordifferentiationofneuronsandsever… 相似文献