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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.
有效分析工艺设计的资源信息和实践经验是CAPP应用系统的关键问题之一.通过对制造工艺资源特征和工艺元信息的分析,对资源-任务匹配中的关键概念进行了定义,建立面向工艺特征的资源特征和任务表达模型,用工艺元和工艺模板表达工艺设计内容.研究以工艺元为基本单元对工艺元序列和工艺实例的资源特征信息进行组织与管理,提出基于工艺模板资源数据库的工艺元和工艺资源特征匹配策略和实施算法,并将该方法应用于工艺设计中资源特征与工艺元的匹配.应用研究表明,该方法为改进工艺任务分配的柔性和适应性提供了一种新的思路.  相似文献   

12.
艺术教育过程是认识过程、实践过程、审美过程和价值过程的有机统一。正确认识和理解艺术教育过程多方面的规定性,才能充分实现艺术教育的功能。  相似文献   

13.
湿法烟气脱硝技术研究进展   总被引:3,自引:0,他引:3  
主要介绍了国内外湿法烟气脱除NOx的研究进展,如碱液吸收法、酸吸收法、氧化吸收法、还原吸收法、生物法和络合吸收法等,分析了各种方法目前存在的优缺点,并针对我国国情对我国烟气湿法净化技术的发展方向提出了建议.  相似文献   

14.
对过程元的它传导过程元和过程元集进行了拓展分析与研究.运用相关分析原理,对过程元与过程元之间的依赖和制约关系进行了分析.当对随机过程在某时刻的过程元进行可拓变换时,由于过程元之间的相关性,会导致与其相关的另一时刻过程元发生传导变换,从而得出它传导过程元和它传导过程元的传导概率函数的概念.将过程元和可拓集合理论相结合,给出了过程元可拓集的概念.在此基础上,对其在工程领域中的应用进行了分析与研究.  相似文献   

15.
为提高产品设计过程的效率,从"产品设计过程亦是产品"的观点出发,提出了基于设计过程知识的设计过程重用方法,设计了基于过程知识的设计过程重用的流程;给出了过程重用系统的模块组成及其结构.并以某重型汽车变速箱设计过程为实例,实证了该方法与流程能有效地提高变速箱设计过程的效率,进而缩短了变速箱的上市周期,提高了变速箱的质量.  相似文献   

16.
一种面向对象CAPP的模型   总被引:2,自引:0,他引:2  
在分析瑞各种CAPP系统原理的基础上,提出了一种基于工艺对象重组方法来设计工艺的思想,建立了一个基于工艺对象的数据库并集工艺过程设计与工艺信息0管理于一体的面向对象的CAPP系统的结构模型,这种模型能继承企业已有的工艺过程,并具有通用性。  相似文献   

17.
探讨了铝液变质、晶粒细化、浇注温度及聚苯乙烯模样等对消失模铝铸件针孔的影响 .研究结果表明 ,干砂消失模铸造工艺冷却速度比树脂砂工艺和粘土砂工艺慢 ,更易产生针孔 ;若用0 .2 %Ti对消失模铸造铝液进行细化处理 ,则可以大大减少冷却速度慢对其针孔形成的不利影响 ,使铝件密度接近或达到树脂砂工艺的水平 .为减少针孔 ,应尽量采用低密度的聚苯乙烯模样 ,并应有一个适当高的浇注温度  相似文献   

18.
基于对软件过程建模基本方法的研究,借鉴软件过程建模基本方法的思想,针对电信企业收入保障过程的特征,提出了一种以活动为中心的电信企业收入保障过程元模型,并探讨了其应用途径.  相似文献   

19.
在地球演化过程中,除了内、外动力地质作用外,宇宙动力地质作用也是一个不容忽视的重要类型。本文讨论了宇宙动力地质作用有别于其他外动力地质作用的几个主要特点,建议将其从外动力地质作用中划分出来,与内动力地质作用、外动力地质作用并列,成为第三种动力地质作用。  相似文献   

20.
香兰素的合成方法进展   总被引:1,自引:0,他引:1  
目的 介绍香兰素合成方法的进展 .方法 根据目前合成状况 ,对香兰素的主要合成方法进行叙述和评价 .结果 愈创木酚法、木质素法是相对成熟的工艺路线 ,对甲酚法正在逐渐完善中 .结论 愈创木酚法占有很大优势 ,对甲酚法具有较好的发展前景  相似文献   

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