查询词典 sand-dune

A thermal expansivity test device consisting of hating unit, attemperating unit, displacement transducer, recorder and so on, was developed to determine the thermal expansivity of new sand, clay-beaded sand, sodium silicate sand, resin bonded sand with th

摘要铸造用砂热膨胀性测试装置，由加热装置、温控装置、移位传感器、记录仪等组成，可实现铸造用原砂（亦可用于粘土型砂、水玻璃型砂、树脂型砂等）的随温和等温热膨胀性测试。

Through detailed analyzing some influencing factiors of sand liquefaction, seven parameters were selected as assessment indexes. They are earthquake magnitude, peak ground surface acceleration, standard penetration value, specific penetration resistance, relative compaction, average particle diameter, and water table. The extension assessment model has been established that was applied to assessment of sand liquefaction potential. The model had been trained by the historical data and has been assessed in virtue of sand liquefaction from the historical data by simulating, and got a excellent result. After introduction of the support vector machine theory, this paper established the assessment model of sand liquefaction based on the support vector machine, and assessed in sand liquefaction from virtue data of some fields in home and overseas with the tool Libsvm, which was programmed based on the support vector machine theory. And got a good coherency between the assessement results and the actual liquefaction.

在详细分析影响砂土液化因素的基础上，选取了震级M、地面最大加速度g_、标准贯入击数N_(63.5)、比贯入阻力P_s、相对密实度D_r、平均粒径D_(50)、地下水位d_w等7个参数作为评价指标，建立了砂土液化势的可拓评价模型，并对历史数据进行仿真评价，取得了较好的应用效果；在对支持向量机的理论进行介绍后，本文建立了基于支持向量机的砂土液化势评价模型，并利用在基于支持向量机理论的Libsvm软件，对若干国内外场地的现场实测数据进行了评价，评价结果与现场表现基本上一致。

The main contents include: the original sand and refractory raw materials, bonding materials, add materials, auxiliary materials, process materials, inorganic sand and core sand binder, organic binder sand, other mold sand, foundry paint, investment casting materials, type of EPC.

其主要内容包括：原砂及耐火原料、粘结材料、添加材料、辅助材料、工艺过程材料、无机粘结剂型砂和芯砂、有机化学粘结剂砂、其他铸型砂、铸造涂料、熔模铸造材料、消失模铸型。

Orthogonal experiment under special condition showed that modifier M has marked effect on properties of no bake sand. Other factors such as modifier B,phosphate concentration and aluminum hydroxide have some impact on properties of binder. It can be found by experiments that strengths of no bake sand are raised notably by binder that modified by modifier B. Modifier B can reduce the strength of no bake sand at high room temperature apart from condition of low room temperature that it can accelerate the reaction and strengthen the sand. Modest content of modifier M in binder has some improvement to anti-wettability of sand. But modifier B has not such notable effect. Electronic microscope shows that near cracks in no bake product there are fibrous shape substances formed when the samples are moistured in high humidity air for sometime.

通过改性剂B对粘结剂自硬砂的性能影响试验发现，改性剂B能显著提高粘结剂自硬砂的强度，在0℃左右很低的环境温度下改性剂M有利于提高自硬砂的反应速度和砂型强度外，但在较高环境温度下，改性剂M均降低粘结剂自硬砂的强度，但是适量的改性剂M有利于改善自硬砂的抗吸湿性，而改性剂B对于改善自硬砂的抗吸湿性的作用不如改性剂M明显，电镜观察发现抗吸湿性较好的自硬砂在高湿度下存放一定时间后，在粘结膜裂纹处会形成一种绒毛状物质，该物质对裂纹具有愈合作用，这种绒毛状物质中具有改性剂M中的某种成分，且含量很高，由此说明改性剂M对提高抗吸湿性有利。

On the basis of making large quantities of investigations, we comprehensively analyze current situation and damage of sand production, and systematically study sand production mechanism of gas well including classification of sand production, influence factors of sand production and process of sand production.

通过大量文献调研，综合分析了气井出砂现状和出砂危害；系统研究了出砂机理，包括了气井出砂分类、气井出砂影响因素和气井出砂过程的研究。

Under function of impeller with high rotating speed, the used sand will be cast to the wearable junk ring to remove the inert film on su rface of the sand via mutual collision and friction between sand and junk ring, impeller and case of machine, sand and sand.

工作时旧砂在高速回转的叶轮作用下，抛向耐磨衬圈，通过砂粒与衬圈、叶轮与机盒、砂粒与砂粒之间的相互碰撞和摩擦，去除砂粒表面的树脂惰性膜。

The vertical distribution of Aeolian sand current Based on the distribution function of lift-off velocity of saltating sand grain, this thesis develops a vertical distribution model of Aeolian flow linking with the number of lift-off sand grains percent time percent sand area. The thesis realizes the combination of microcosmic researches and macroscopical researches of Aeolian wind sand and solves primarily the isjunction of microcosmic researches and macroscopical researches.

4风沙流的垂向分布以本文获得的沙粒起跳初速度分布函数为纽带，结合本文获得的单位时间单位面积沙床起跳沙粒数，建立风沙流的垂向分布模型，实现风沙运动宏观研究和微观研究相结合，初步解决长期以来宏观与微观研究相脱节问题。

In the paper the author relates systematically the research fruits in the program of Research on Sand Slurry Abrasion Mechanisms of Dredging Conditions and New Wear-Resistant Materials. The main contents and innovations are listed as follows.Summarized and analyzed are the wear researches and developments, and the methods of increasing materials wear-resistance. From the viewpoint of the characteristics of two-phase liquid sand slurry wear, combined with the examination and study on easily damaged workpieces, the wear failures basic rules are pointed out, of the pump shell and the cutter-piece on service, and the general principles of material wear-resistant designs put forward. The sand slurry abrasion tester has been designed and developed which can simulate general dredging conditions. Summarized and presented are the position-exchange measuring method of sand slurry abrasion test and the experiment specification of sand slurry wear test of dredging conditions.

文中系统论述了作者在疏浚工况泥沙磨损机理及其耐磨新材料课题研究中的工作成果，主要研究内容和创新点如下：总结分析了磨损研究动态和提高材料耐磨性的方法；从两相流泥沙磨损的特点出发，结合对失效易损件的考察研究，分析指出了现役泥泵壳和绞刀片磨损失效的基本规律，提出了材料耐磨损设计的基本思想；设计研制了能模拟疏浚工况的泥沙磨损试验机，总结提出了泥沙磨损试验换位测试法和疏浚工况泥沙磨损试验规范。

Therefore a GD sand-screening pipe is developed, which is helpful to the environment protection. This new sand-screening pipe consists of center pipe, sand filter and guide shoe. The center pipe is machined from 64mm tubing, and the sand filter is made from silica sand, cement, additive.

这种环保型滤砂管由中心管、滤砂器及引鞋组成，中心管采用 6 4mm油管加工而成，两端为特种 6 4mm平式油管螺纹，管体上每米均匀分布 72个直径 10mm孔眼；滤砂器是根据不同技术标准筛选不同粒度的石英砂、油井水泥、添加剂和水按配比加工压制的。

The formation sand flow is one of an important factor to effect the nonnal production of oil wells. Sand pump technology is an effective way to control the fine sand in the artificially lifted wells. Sand control pump is main tool for sand disposal.

地层出砂是影响油井正常生产的重大因素之一，排砂工艺是针对细粉砂在机采井上采取的一种防砂工艺，防砂泵是目前主要的排砂工具。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。