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1.
Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anisotropic suspension were reported.A new concept of simple anisotropic fluid was introduced.On the basis of anisotropic principle,the simple fluid stress behaviour was described by velocity gradient tensor F and spin tensor W instead of velocity gradient tensor D in the classic Leslie-Ericksen continuum theory.Two relaxation times analyzing rheological nature of the fluid and using tensor analysis a general form of the constitutive equation of co-rotational type was introduced.More general model LCP-H for the fluid was developed.The unsymmetry of the shear stress was predicted by the present continuum theory for anisotropic viscoelastic fluid-LC polymer liquids.The influence of the relaxation times on material functions was specially studied.It is important to study the unsteady vibrational rotating flow with small amplitudes,as it is a best way to obtain knowledge of elasticity of the LC polymer,i.e.dynamic viscoelasticity.For the shear-unsymmetric stresses,two shear stresses were obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) were introduced by the constitutive equation which was defined by rotating shear rate introduced by author.For the two stability problems of fluid,such as stability of hydrodynamic flow and orientational motion,were discussed.The results show that the polymer suspension systems exhibit anisotropic character.The PNC systems can exhibit significant shear-thinning effects.For more concentrated polymer nano-suspensions,the first normal stress difference change from positive to negative,which is similar to LC polymer behavior.  相似文献   

2.
针对民办高校所需办学经费无国家财政拨款,全部为自筹资金的现状,分析了形成当前民办高校融资难的原因,既有信贷政策、银行方面的因素,也有民办高校自身的因素.提出民办高校要生存,要发展,光靠举办者投入或捐赠以及每年的学费收入是不够的,还需要积极拓展更多融资渠道解决办校融资难的问题.  相似文献   

3.
根据细粒磁性物回收工艺中需要使用预磁器的要求,研究预磁器的工作时序、充放电回路的电器元件特性和电路电压、电流特征.设计的电磁预磁器磁场强度高,能耗低,性价比高.对预磁化电路展开理论计算和推导.首次提出脉冲振动预磁器系统结构,将RLC电路振荡波形转变为振动波形,形成"脉振"高场强,延长了线圈的使用寿命.经实际运行检验,该装置性能稳定,效果好,能耗低,每小时耗电仅0.8 kW,在预磁器领域是一项创新的实用技术.  相似文献   

4.
作为城市污水热能资源化的基础研究,根据理论分析方法,对有效利用城市污水所赋存的热能时,其节能效果和对减轻大气污染的作用进行了若干分析和探讨.分别计算了流量为1 m3/s时城市污水赋存的热量,以及采暖面积为1万m2时所需的城市污水及赋存的热量,与空调、锅炉相比产生相同热量时的一次能和二次能的消减量,以及相应条件下的污染物年间(采暖期)消减量等.  相似文献   

5.
Using the constitutive equation of co-rotational derivative type for anisotropic viscoelastic fluid-liquid crystalline(LC),polymer liquids was developed.Two relaxation times are introduced in the equation:λn represents relaxation of the normal-symmetric stress components;λs represents relaxation of the shear-unsymmetric stress components.A vibrational rotating flow in gap between cylinders with small amplitudes is studied for the anisotropic viscoelastic fluid-liquid crystalline polymer.The time-dependent constitutive equation are linearized with respect to parameter of small amplitude.For the normal-symmetric part of stress tensor analytical expression of the shear stress is obtained by the constitutive equation.The complex viscosity,complex shear modulus,dynamic and imaginary viscosities,storage modulus and loss modulus are obtained for the normal-symmetric stress case which are defined by the common shear rate.For the shear-unsymmetric stress part,two shear stresses are obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) are given by the constitutive equation which are defined by rotating shear rate introduced by author.The dynamic and imaginary viscosities,storage modulus and loss modulus are given for each complex viscosities and complex shear modulus.Using the constituive equation the rotating flow with small amplitudes in gap between two coaxial cylinders is studied.  相似文献   

6.
玉米中转基因成分的定性PCR检测   总被引:1,自引:0,他引:1  
利用改良 CTAB 法提取玉米产品的基因组 DNA,应用 PCR 检测方法,并以玉米特异性内源基因 IVR 为内参,花椰菜花叶病毒 35S 启动子(CaMV35S 启动子)、农杆茵胭脂碱合成酶终止子(NOS终止子)为靶基因检测玉米中是否存在转基因成分.实验结果表明,有些玉米样品中存在转基因成分,表明市场上存在未经标识的转基因玉米及其加工品.  相似文献   

7.
利用晶体的双折射现象和它的基本性质,采用现代光纤和CCD摄像放大技术手段研究了双偏振光的叠加和干涉现象,讨论了学生在教学中不易理解的难点问题.  相似文献   

8.
科技期刊版式设计略谈   总被引:1,自引:0,他引:1  
对科技期刊版式设计中的标题、插图与空白的处置进行了分析探讨,认为科技期刊版式设计在总体上应是追求格式一致与节奏变化的统一,整体性与连贯性的统一.布局合理的版式设计带给期刊的是整体的和谐美,别具风格的版式设计标志着期刊的个性特征.  相似文献   

9.
对一国或多国军备竞赛的数学模型进行了研究.单独一国的经济增长服从Horrod-Domer模型,但当多国一起竞争时,弱国将遭受前所未有的严重挑战.通过研究超级大国、另一大国和弱国这三个国家之间军备竞赛稳定性问题,得到了军备竞赛稳定性的条件.  相似文献   

10.
Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedance function transfer method. Firstly, the sediment under rock-socketed pile was assumed to be fictitious soil pile with the same sectional area. The Rayleigh-Love rode model was used to simulate the rock-socketed pile and the fictitious soil pile with the consideration of the lateral inertial effect of large-diameter pile. The layered surrounding soils and bedrock were modeled by the plane strain model. Then, by virtue of the initial conditions and boundary conditions of the soil pile system, the analytical solution of the vertical dynamic impedance at the head of rock-socketed pile was derived for the arbitrary excitation acting on the pile head. Lastly, based on the presented analytical solution, the effect of sediment properties, bedrock property and lateral inertial effect on the vertical dynamic impedance at rock-socketed pile head were investigated in detail. It is shown that the sediment properties have significant effect on the vertical dynamic impedance at the rock-socketed pile head. The ability of soil-pile system to resist dynamic vertical deformation is weakened with the increase of sediment thickness, but amplified with the increase of shear wave velocity of sediment. The ability of soil pile system to resist dynamic vertical deformation is amplified with the bedrock property improving, but the ability of soil-pile system to resist vertical vibration is weakened with the improvement of bedrock property.  相似文献   

11.
本文阐述了复杂反应机理与反应动力学方程之间的关系,指出简化复杂反应机理的必要性,建立了简化复杂反应机理的代数方法,并以乙烷裂解反应作为例子给与说明。  相似文献   

12.
本文对变腔深双层微穿孔板消声器进行了研究,提出了一种新的设计方法:即根据吸声系数最大原理选定双层微穿孔板消声器的腔深值。这种方法拓宽了消声器的消声频带宽度,改善了消声器的消声性能。这种设计方法已经实践检验,取得了良好的效果,从而证明这种方法是可行的。同时,本文还对双层傲穿孔板消声器的失效频率进行了讨论。  相似文献   

13.
本文通过对卷烟切丝机刀片补偿机构的分析,导出了一类特殊形式的组合机构,并对这类组合机构的构成方法及重要特性进行了分析和论证。  相似文献   

14.
近年,各油田建立了测井数据库,但特殊测井数据还是以“图片”的形式保存,这对特殊测井数据的继续使用带来很多不便。在分析了特殊测井数据基础之上,本文介绍一种新的测井数据库管理方法,将不同解释系统下形成的成果数据、图形文件等资料在Oracle数据库中有序存放与管理,解决了特殊测井大块数据在网络环境下的高效传送难题,极大地提高了特殊测井数据的再次利用效率,实现了特殊测井“数据型”图件的网上显示。  相似文献   

15.
作者研制了一种用于野战综合通信训练模拟系统中的网控系统,本文介绍了该系统的功能、结构、工作原理和软件控制流程,叙述了该系统实现的主要技术及其优点,最后对实际应用进行了一定的分析。  相似文献   

16.
研究了大规模稀疏线性方程组的预条件迭代求解算法。结合Krylov子空间方法和SOR迭代,给出了一个新的求解算法,即变预处理子SOR-双共轭残量法,同时给出了算法的收敛性分析。数值实验显示了算法的快速收敛性。  相似文献   

17.
在数学中及工程技术中,对有关极值问题的讨论是一个非常重要的课题,对于这些问题的讨论有时可化为一些等式或一些行列式的计算。对一类极值问题进行了认真讨论和分析,给出了一类行列式的计算,并推广了阶乘的概念,且得到一类正定矩阵  相似文献   

18.
针对不完备信息系统的知识获取,提出了一种基于相容度的变精度粗糙集模型,该模型是变精度粗糙集模型在不完备信息系统中的拓展.定义了这种模型上的知识约简,并给出了求约简的一个启发式算法.最后通过实例分析说明了算法的有效性.  相似文献   

19.
本文利用工艺链原理,对CA10发动机铝活塞的机械加工工艺过程进行了整体研究;分析了活塞销孔中心线对裙部中心线垂直度质量指标在各。序中的控制情况;研究了各工序间的相互关系和影响,得出了相关结论。  相似文献   

20.
本文给出了一个判别马尔科夫链具有普遍历性的充分条件,并给出了马尔科夫链的一个新的应用,即利用马尔科夫键来定量地评价教师的教学效果,这种评价方法具有比目前各种评价方法更为科学合理的特点。  相似文献   

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