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1.
Comprehensive tests on Hangzhou intact soft clay were performed, which were used to obtain the soils’ critical response to undrained dynamic stress paths under different combinations of principal stress orientation. The different combinations included cyclic principal stress rotation (CPSR for short), cyclic shear with abrupt change of principal stress orientation (CAPSO for short) and cyclic shear with fixed principal stress orientation (CFPSO for short). On one side, under all these stress paths, samples have obvious strain inflection points and shear bands, and the excess pore water pressure is far from the level of initial effective confining pressure at failure. Stress paths of major principal stress orientation (α) alternating from negative and positive have quite different influence on soil’s properties with those in which α is kept negative or positive. On the other side, due to the soil’s strongly initial anisotropy, samples under double-amplitudes CPSR and CAPSO (or single-amplitude CPSR and CFPSO) have similar properties on dynamic shear strength and pore water pressure development tendency when α is kept within ±45°, while have quite different properties when α oversteps ±45°.  相似文献   

2.
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   

3.
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   

4.
20世纪30年代,向现代派艺术学习的从艺者成立了艺术团体决澜社,虽然它并没有如其发起者所预想的那样造成狂澜决堤之势,但终究为当时的画坛打开了一扇放眼世界的窗口,并且提出了"现代中国绘画艺术与现代世界艺术合流"的问题.是他们让人们意识到世界艺术日趋多元化的格局的到来.通过对其先锋性和局限性的思考让我们对于中国艺术的发展道路了解更加深入.  相似文献   

5.
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   

6.
文章试图从两方面解读连战先生深厚的民族情.这种民族情一方面来源于他的家族,连战的先祖到台湾死也不臣服清,曾祖父至父亲三代以各种形式坚持抗日及父母对他言传身教;另一方面与他早年在祖国大陆的生活经历有关,从他对抗战和日本的态度及祖国大陆寻踪等方面体现出来.  相似文献   

7.
在美国西南部和墨西哥西北部,雨季的降雨量占全年降雨量的一半以上,这些雨季降雨通常强度大且难以预测.在雨季到来的时候,来自加利福尼亚湾和墨西哥湾等海洋上的湿润气流经常会给太阳炙烤的土地带来暴雨的突袭.这种突发强降雨可能会冲毁道路,在短时间内诱发泥石流等自然灾害,不仅会对农业和生态系统造成重大影响,也严重威胁着人类的生命及财产安全.  相似文献   

8.
在110℃下,加热搅拌乙酰胺和氯化锌混合物制备了CH3CONH2/ZnCl2低共熔溶剂,对其结构进行 了电喷雾电离质谱分析、红外分析和黏度分析。以CH3CONH2/ZnCl2作为萃取剂和催化剂,H2O2作为氧化剂,氧 化脱除模拟油中的噻吩硫化物。对n(ZnCl2)/n(CH3CONH2)、n(H2O2)/n(S)、反应温度、剂油体积比和不同硫化 物对脱硫率的影响进行了考察。在模拟油体积5mL、n(ZnCl2)/n(CH3CONH2)=0. 4、n(H2O2)/n(S)=8、剂油体 积比1∶3、反应温度70℃、反应时间200min的最佳条件下,二苯并噻吩的脱除率达到87. 12%。经过5次循环之 后,脱硫率略有降低。  相似文献   

9.
从《劝学篇》看张之洞的立宪思想   总被引:1,自引:0,他引:1  
一般论者认为,张之洞的<劝学篇>是反"民权"的;其核心创获--"中体西用"论中的"西用",仍停留在"西技西艺,,层面.本文通过分析<劝学篇>中张之洞对西方民权、立法、议院的理解,认为他反对"民权"却不反"立宪",并且对西方立宪制度中的"立法"与"议院"颇为认同,不无效仿之意;张之洞的"立宪"在于"保教",这大大限制了他对"西政"的吸收.尽管如此,<劝学篇>仍不失为张之洞立宪思想的首次表达之作.  相似文献   

10.
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   

11.
探讨了 Banach 代数中的行列式理论.给出了具有单位元的迹 Banach 代数具有行列式的充要条件.  相似文献   

12.
对近年来非织造布滤料的研究进展做了简要综述,介绍了内部结构的研究及表征、过滤性能及其影响因素、过滤过程的计算机模拟,指出进一步发展所需要解决的问题。  相似文献   

13.
单面约束系统的微分变分原理与运动方程   总被引:2,自引:0,他引:2  
研究单面约束力学系统的微分变分原理和运动方程。方法利用D'Alembert原理建立D'Alembert-Lagrange原理.Jourdain原理和Gauss原理,结果与结论得到系统的微分变分原理和带乘子的Euler-Lagrange形式,Nielsen形式和Appell形式的运动方程。  相似文献   

14.
q 是一个正整数,所谓 q-树的图是递归定义的:最小的 q-树是完全图 Kq,一个 n+1阶的 q-树是通过在 n 阶 q-树上加上一个新点并连接这点与 n 阶 q-树中任意 q 个互相邻接的点而获得,其中 n≥q.1-树我们通常称为树.在本文中,证明了对任意正整数 q,q-树是可重构的.  相似文献   

15.
采用毛细管区带电泳模式,以β-环糊精为手性选择剂分离了药物扑尔敏的光学对映体.考察了在不同背景电解质 pH 值尤其是较低 pH 值下环糊精浓度对对映体表观淌度差的影响,并研究了有机改性剂尿素在分离中的作用.  相似文献   

16.
利用层状球形夹杂在无限大基体中的局部化关系及平均应力场理论,给出了一种方法来分析含 n 种层状球形夹杂所构成复合材料的弹性模量.对于文献给出的空心玻璃球和高分子基构成的复合材料,该理论的预测与实验吻合很好.当表层稍失时,该理论退化为传统的 Mori-Tanaka平均应力场理论.  相似文献   

17.
本文研究Java环境下的可视化Web开发。以高校研究生管理信息系统为例,探索Sun Java Creator的数据源配置、可视化Web组件、行集、Session Bean等在Java Web中的应用。  相似文献   

18.
介绍了指标公式定义的数据结构及存储结构 ,描述了对指标公式进行计算的原理及工作流程 ,给出了在PHP下实现了的程序代码。  相似文献   

19.
以松节油中的α-蒎烯为原料,SeO2为氧化剂,无水乙醇为溶剂,在回流温度下反应5h生成桃金娘烯醛,产率为61%,在430℃60kPa下通过黄铜丝床层0.3-0.5s异构化反应生成紫苏醛,采用亚硫酸氢钠法,提纯紫苏醛后用盐酸羟胺进行肟化反应生成紫苏糖,总得率大约20%。  相似文献   

20.
在弱碱性介质中,Pb^2+,Bi^3+,F3^2+,Mn^2+与PAR显色剂形成水溶性有配合物,其吸收光谱严重重叠。本采用均匀设计与PLS方法结合,对这4种且分的混合体系进行分析,实现了不经分离而直接同时测定Pb^2+,Bi^3+,Fe^3_,Mn^3+的含量,相对标准偏差小于0.02。  相似文献   

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