查询词典 sand-dune

Whether sand can saltate from sand bed surface and quality of sand incipience are very important to the sand transport and the form of wind-blown-sand. The quality of sand incipience involved with many kinds of parameters, such as incipient velocity, incipient angle etc.

沙粒能否起动以及起动质量如何，如起动初速度、起动角度等参数都直接关系到沙粒的输运和风沙两相流形成。

So far, the main aspects studied include: the forecast of sand transport rate, the spatial distribution of sand and wind field, the mechanism of start and maintenance of sand transport, the development process of sand ripple, the influence of physical character of the sand bed on sand motion and so on.

目前的研究成果主要涉及到风沙输运的输沙率的预测、沙粒和风场的空间分布规律、风沙运动的起动机制和维持机制、沙波纹的产生和发展机制以及地表物理性质的改变对风沙运动的影响等。

Aiming at disjunction of microcosmic researches and macroscopical researches and status quo of theory basis researches of Aeolian sand movement near the sand bed, based on plenty of experiment data in wind tunnel, this thesis studies some microcosmic researches including the number of lift-off sand grains percent time percent sand bed area and relative movement parameters of saltating sand grains by combined methods of mechanical and statistical mechanical theories. Then, this thesis develops in advance a relation between the microcosmic researches and macroscopical researches in order to describe truly the theory model of some macroscopical physical variable of Aeolian sand movement.

本文针对当前风沙运动微观与宏观研究相脱节、准确描述近地面风沙运动规律的理论基础薄弱的现状，基于大量风洞实验数据，通过对沙床面单位时间单位面积起跳沙粒数、沙粒跃移运动过程中相关参数等微观问题的研究，力图建立风沙运动微观与宏观研究的联系桥梁，以期能够准确描述风沙运动宏观量变化的理论模型。

The results of calculations showed that the maximum increments in saltation height and horizontal distance due to the Magnus force were 10.2 and 24.9%, respectively, and that both increments increased with increasing lift-off angle. The maximum increments in saltation height and horizontal distance of sand grains caused by the Saffman force were only 4.6 and 3.7%, respectively. The vertical concentration distribution of Aeolian sand flow follows exponential function distribution whether or not force analysis of saltating sand grains includes Magnus and Saffman force. The effect of Magnus and Saffman force on the vertical concentration distribution of Aeolian sand current makes the rate decrease near sand bed and it is consistent with the effects of Magnus and Saffman force on the saltation height and distance of sand grains.

Magnus力对跃移高度和水平距离产生的最大增量分别可达到10.2%和24.9％，这两个增量均随起跃角度的增加而增大；Saffman力对跃移高度和水平跃移距离产生的最大增量分别为4.6%和3.7%；是否考虑Magnus与Saffman力，风沙流垂向质量百分浓度均服从指数函数分布，Magnus与Saffman力使得风沙流垂向质量百分浓度较不考虑它们的作用呈现出底层的比例较小，上层较大，Magnus与Saffman力对跃移高度的影响基本与其对风沙流垂向质量分布的影响一致，不过Magus力对风沙流垂向质量百分浓度分布影响较大，0-2cm范围内尤为强烈(7.16-10.81)，其他高度层(2-20 cm)的影响相对较小(0-2.95)。

Main Products: environment-friendly housing sandblasting sand blasting machine shot blasting machine electronic burrs processing standard processor confined blasting sand blasting machine, trolley wheel sealed blasting machine, waste-to-pressure confined blasting machines, drum type automatic blasting machine, sand blasting whirlwind drum machine, open sand blasting machine, wet sand blasting machine, sand blasting zone automatic machine, automatic take-off and landing disc sandblasting machine, sandblasting Cyclones closed large machines, conveyor-style blasting machine , rotary disc automatic sandblasting machine, sandblasting machine for automatic delivery, automatic plate glass sandblasting machine, all kinds of industrial dust collector, large-scale environmental protection, such as sandblasting room.

主要产品：环保型喷砂房喷砂机抛丸机电子毛边处理机喷砂加工标准型密闭喷砂机、台车转盘密闭式喷砂机、压力密闭回收式喷砂机、滚筒式自动喷砂机、旋风式滚筒喷砂机、开放式喷砂机、湿式喷砂机、环带式自动喷砂机、升降圆盘式自动喷砂机、旋风密闭式大型喷砂机、输送式喷砂机、回转式圆盘自动喷砂机、连续输送自动喷砂机、平板玻璃自动喷砂机、各式工业用集尘器、大型环保喷砂房等。

Our main products: dredging ship, pumping sand barge, sand screening machine, Dump Sand Barge, gravel Featured equipment, gold machinery, iron ore extraction equipment, river pebbles and weathered broken equipment, screw sand washing machines, conveyor-type automatic loading sand machinery, etc.; a total of ten series more than 30 specifications for the user to choose, and geographic environment based on user design and manufacture of special products, factory production of mechanical energy at the same time the completion of dredging excavation, screening, separation of several procedures, one-time production of qualified products, divided into sand, stone and waste in the advantage of high efficiency and low cost.

本厂主要产品：挖沙船，抽沙船，筛沙机，自卸运沙船，砂石精选设备，淘金机械，铁砂提取设备，河卵石及风化破碎设备，螺旋洗沙机，输送式自动装沙机械等；共有十大系列三十多个规格供用户选择，并根据用户地理环境设计制造异型产品，本厂生产的挖沙机械能同时完成挖掘，筛选，分离几个程序，一次性生产出合格产品，分为沙石，中石及废料，其优点效益高，成本低。

The process of sand absorption is:(1) the vibration head vibrates and losses the sand layer, and supply high pressure air into the sand absorption head;(2) the high pressure air generates negative pressure in the sand absorption pipe when it is discharged out from the sand absorption;(3) the sand absorption head and the vibration are shifted downwards and maintains the water flow straightly.

取砂土的过程为：(1)振动头振动松散砂土层，同时向吸砂头供入高压空气；(2)高压空气通过吸砂头从排砂管向上排出的过程中，在吸砂管内产生负压，吸砂管将管口处的水和砂土吸入到吸砂头内，在高压气流作用下，吸砂头内的砂、水和气混合而成的三相流通过排砂管排出到受砂船上；(3)在吸砂的过程中，适时地将吸砂头和振动头下移并保持钻孔套管中的水流畅通。

The device includes a drill spigot inserting into the marebase sand layer through the upper cover soil layer, there sets air inlet, sand discharging pipe and vibration connecting pipe in the drill spigot; there sets a sand absorption head on the bottom of the air inlet and sand discharging pipe; the bottom of the vibration connecting pipe connects with the vibration head; the sand absorption head is made up of a centre cavity, ring cavity and sand absorption pipe.

该装置包括一穿透上部覆盖土层插入到海底深埋砂土层的钻孔套管，在钻孔套管内，设有进气管、排砂管和振动连接管；进气管和排砂管的下端连接一个吸砂头；振动连接管的下端连接振动头；吸砂头由一中心腔室、环状腔体和吸砂管构成。

Domestic companies to introduce advanced production equipment, production and processing dried Mica Powder, Mica Powder wet system, ordinary quartz sand, semi-refined quartz sand, fine quartz sand, high purity quartz sand, limestone, calcium carbonate, precipitated calcium carbonate, dolomite powder , vermiculite powder, feldspar powder, maifanite, tourmaline, bauxite, sand, pebbles, sand, building sand and other non-metallic mineral products can be customized according to user needs processing.

公司引进国内先进生产设备生产加工干制云母粉、湿制云母粉，普通石英砂、半精制石英砂、精制石英砂、高纯石英砂，石灰石、重质碳酸钙、轻质碳酸钙，白云石粉，蛭石粉，钾长石粉，麦饭石，电气石、铝矾土，彩砂，鹅卵石，河砂、建筑砂等非金属矿产品，可根据用户需要定做加工。

Company will supply a variety of sandblasting abrasive, complete specifications, the warehouse store has metal abrasive (steel balls, stainless steel balls, Steel, stainless steel sand, steel pill, zinc pills, capsules aluminum), non-metallic abrasives (glass beads, corundum sand, quartz sand, garnet sand, walnut sand, plastic sand, nylon sand), etc., be able to quickly meet the diverse needs of customers.

公司供应各种喷砂磨料，规格齐全，仓库内储存有金属磨料（铸钢丸、不锈钢丸、钢砂、不锈钢砂、钢丝切丸、锌丸、铝丸）、非金属磨料（玻璃珠、刚玉砂、石英砂、石榴砂、核桃砂、塑胶砂、尼龙砂）等，能够快速满足客户的不同需求。

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。