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介绍了采用大分子溶液直接插层有机粘土制备聚苯乙烯／粘土纳米复合材料合成技术．实验结果表明：聚苯乙烯大分子链在柠烯溶液中有着极好的溶剂化作用，与改性有机粘土能够发生有效插层作用，同时粘土剥离物增强材料可以纳米级尺寸均匀分布在聚合物基体．阐述了插层剂选择及有关阳离子表面活性剂分子修饰原则及合成原理以及重点讨论了聚合物溶液直接插层原理及热力学条件和影响因素。 相似文献
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《世界儿童(小学生阅读版)》2014,(11):20-22
游戏“愤怒的小鸟”让我们认识了一群疯狂小鸟。现在，只要动动手，就能创作出属于你的小鸟战队哦。
材料：“贝蒙”超轻粘土，粘土工具棒等
制作方法：
1．先把粘土搓成水滴状，然后轻轻弯曲两头，用来做小鸟的身子。 相似文献
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Bas van DIJK 《浙江大学学报(A卷英文版)》2018,(8)
目的:吸力式基础具有投资费用低、施工时间短、无噪音和可重复使用等优点,因此被广泛应用在海洋工程领域。本文针对吸力式基础设计中的关键问题,主要综述现有设计理论,指出理论缺陷,并给出设计建议。创新点:综述砂土、粘土和成层土中吸力式基础的安装、回收、基础承载力、基础沉降和服役性能中的关键科学问题和现有设计理论。方法:1.基于文献报道的现场试验和模型试验,针对吸力式基础安装过程中的沉贯阻力、临界吸力和土塞效应,评估现有设计理论的准确性;2.分析粘土和砂土中吸力式基础的完全排水、完全不排水和部分排水条件下静力和循环承载力计算理论;3.针对吸力式基础的长期服役性能,分析荷载引起的基础变形、固结沉降、循环再固结沉降和极端荷载下的"棘轮效应"。结论:1.现有的吸力式基础安装中沉贯阻力计算理论没有普适性;对于临界吸力的计算,由于没有考虑"土拱效应",理论计算值均低估了安装吸力。2.对于粘土中吸力式基础承载力的计算需要考虑循环作用下土体的强度弱化和基础-土间空隙引起的承载力降低,而砂土中基础承载力计算需要考虑排水条件的影响。3.对于吸力式基础的长期服役性能,特别是基础变形的计算,目前还缺少成熟的计算理论。 相似文献
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小麦亲本千粒重遗传效应分析 总被引：2，自引：0，他引：2
利用不完全双列杂交设计试验,采用MINQUE（1）法直接估算方差分量,采用AUP法预测遗传效应值,对10个小麦亲本材料的干粒重遗传效应进行研究．结果表明,千粒重的遗传同时受基因加性效应和非加性效应的共同作用,以加性效应为主．千粒重性状后代稳定快,早代选择有效．亲本材料周麦18号和豫麦34号具有较高的加性遗传效应．皖宿9908和郑9705次之。可作为粒重改良的理想亲本． 相似文献
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唐忠 《湖南城市学院学报》2003,24(6):34-37
建立了粘质土路基稳定性分析中求算相关角值的数值公式，并在此基础上重新编制了相关角值表，可替代流行至今但精度较差的现行角值表．对于软粘土路基的稳定性分析，通过力学分析建立了某一边坡高度的各种可能破坏面的最小稳定系数Kmin的解析公式．在与现行规范法对比的基础上，阐明了该法的实用价值． 相似文献
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五年制高职教育的学生处于一个复杂的信息时代．有着复杂的心理状态,班主任是班级的灵魂,必须多角度地进行班级学生的管理,可应用一定的心理效应,如“暗示效应”、“定型效应”、“门槛效应”、“奖罚效应”、“链状效应”、“南风效应”和“破窗效应”等,使班主任工作更好地进行,并且达到事半功倍的效果。 相似文献
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巨磁阻效应的简单应用 总被引：1，自引：0，他引：1
巨磁电阻效应是指物质在磁场作用下电阻发生巨大变化的现象，或称为巨磁阻(Giant MagnetoResistance。简称GMR)效应．1988年M．N．Baibich首先报导了在Fe／Cr金属多层膜中发现了具有50％的巨磁电阻效应，受到了各国科学家的重视．IBM公司在1997年宣称巨磁阻效应可被用于制作硬盘驱动器的读出磁头，并预计仅仅采用新的GMR材料就可以使原来每张磁盘的容量由1G提高到20G．巨磁阻效应的另外的重大应用是永久磁存储器和GMR传感器． 相似文献
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鸡西煤田二人班区球粘土广泛发育,分布面积广,储量丰富。通过对球粘土特征的研究分析,阐述了球粘土品位及工业用途,估算了球粘土资源量,为本区球粘土的开发利用提供了建议。 相似文献
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In a landfill, excessive tensile strains or failure of the liner system due to localized subsidence underneath the geosynthetic liner, is a concern in design and operation of the landfill. The localized subsidence can be commonly withstood by reinforcements such as geogrids. A total of nine model tests were carried out to study the influence of soil arching in overburden sandy soil on the geosynthetics and the interaction between the soil and the geosynthetics. The localized subsidence was modeled by a strip trapdoor under the geosynthetic reinforcements. The reinforcement includes several layers of polyvinylchlorid (PVC) membrane or both PVC membrane and a compacted clay layer. Test results show that the vertical soil pressure acting on the geosynthetics within the subsidence zone is strongly related to the deflection of the geosynthetics. The soil pressure acting on the deflected geosynthetics will decrease to a minimum value with respect to its deflection if the final deflection is large enough, and this minimum value is almost independent of the overburden height. Otherwise, the deflection of geosynthetics cannot result in a full degree of soil arching, and the soil pressure within the subsidence zone increases with the increase of overburden height. Deflections and strains of the geosynthetics obviously decrease with the increase of their tensile stiffness. The presence of a compacted clay layer buffer can therefore reduce both deflections and strains of the geosynthetics. Finally, a composite liner structure is recommended for landfills to withstand the localized subsidences. 相似文献
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陈颖平 《辽宁科技学院学报》2011,13(4):25-26
对杭州某粘土进行循环荷载作用下的动强度研究,发现土体结构破坏与否对土的动强度有很大影响,尤其是在动应力较小的情况下。各固结压力下均存在着一个临界最小动应力比。 相似文献
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刘红 《临沂师范学院学报》2007,29(5):137-140
小郭泥塑艺术起源于清代咸丰年间,其艺术技艺高超,艺术成果丰硕。小郭泥塑外部造型完整统一,夸张、简洁而不粗俗。小郭泥塑出路开拓需要强化保护意识,强化教育意识,强化与科学结合,强化市场观念,强化创新思维。这样小郭泥塑就能得到继承和发展。 相似文献
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Theone dimensionalinfinitesimalstrainconsolida tiontheorydevelopedbyTerzaghiassumedthattheper meabilityandcompressibilityoftheclayremainedcon stantduringconsolidationunderaparticularincrementofload[1] .So ,inpractice ,thetheorywasonlyapproxi matelysatisfying .Variousresearcheshavesoughttoex tendtheclassicaltheorytotakeaccountofthevariationofpermeabilityandcompressibilityduringconsolidationinoneormoreways .Thecompressibilityandcoefficientofpermeabilitywereassumedtobefunctionsofthede greeofsatur… 相似文献
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高职教育随着经济的发展和社会的进步呈现新的趋势,现代陶艺正朝着多元化、多层面的方向良性发展。陶艺教学不应只围绕着陶艺创作来进行,如何继承、发展、创新是摆在教学中的首要问题,因为创新是陶艺创作的灵魂,同时进行产学研结合,会使高职陶艺教学更加完善。 相似文献
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In this paper we propose a degradation model to describe the damage-dependent behavior of saturated soft clay under cyclic loading, which is then applied to the analysis of a caisson breakwater. The degree of damage and remolding of soft clay is quantified by a damage parameter related to the accumulated plastic deviatoric strain. Through the correlation between the maximum pore pressure and the undrained strength of soft clay, we obtain a damage-dependent degradation model that employs the post-cyclic undrained strength degradation coefficient in terms of the cyclic stress ratio and the number of cycles. Based on the Tresca yield criterion, the degradation model of undrained strength of soft clay is numerically implemented in the user interface USDFLD of ABAQUS. The performance of this model is verified by a comparison between numerical results (finite element method) and experimental data (cyclic triaxial test). The model is applied to the numerical simulation of a caisson breakwater resting on a partially sand-filled soft clay seabed under cyclic wave loading. The cyclic stress distribution, pore pressure development, and strength degradation of the seabed soil are presented to illustrate the applicability and efficiency of the model in the analysis of the interaction between offshore structures and soft ground. 相似文献
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Conclusion Novel polymer/clay nanocomposites can be prepared by varying two parameters; first by optimizing polymer to clay ratio and
second by varying the processing techniques. An exploration in making the polymer/clay nanocomposites with different clays,
surfactants and polymers is a continuing subject of research and interest to both academia and industry. 相似文献
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Failure criterion of saturated soft clay is studied under cyclic loads through different experiments. A large number of cyclic torsional shear and cyclic triaxial tests on saturated soft clay under unconsolidated undrained condition are conducted. From the test result analysis, it is seen that the failure of saturated soft clay under static and cyclic loads satisfies Mises criterion. The result from different test stress states is not related to the test stress states or confining pressures. It can be applied in general stress states. Then according to the Mises criterion, the equivalent relationship on failure moment between the test stress state and the general stress state can be established. So the cyclic mechanics characteristics of saturated soft clay at failure moment are clarified in this paper. Furthermore, a theory basis is provided for using pseudo-static elasto-plastic cyclic strength model to evaluate cyclic bearing capacity. 相似文献
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ZHAN Liang-tong CHEN Ping NG C.W.W. 《浙江大学学报(A卷英文版)》2007,8(5):699-706
A laboratory study was carried out on both natural and compacted specimens to investigate the complex soil-water interaction in an unsaturated expansive clay. The laboratory study includes the measurement of soil-water characteristic curves, 1D free swelling tests, measurement of swelling pressure and shrinkage tests. The test results revealed that the air-entry value of the natural specimen was quite low due to cracks and fissures present. The hydraulic hysteresis of the natural specimen was relatively insignificant as compared with the compacted specimen. Within a suction range 0 to 500 kPa, a bilinear relationship between free swelling strain (or swelling pressure) and initial soil suction was observed for both the natural and compacted specimens. As a result of over-consolidation and secondary structures such as cementation and cracks, the natural specimens exhibited significant lower swelling (or swelling pressure) than the compacted specimen. The change of matric suction exerts a more significant effect on the water phase than on the soil skeleton for this expansive clay. 相似文献