回流

The results show that:(1) the dynamical conditions for returnflow events are a little different from other rainfall events, with divergence and anticyclonic circulation at lower levels;(2) the air of the returnflow from Northeast China, through the Bohai Sea, then to North China, is relatively dry.

结果表明：涡度和散度的垂直分布与一般的降水过程不同，低层存在辐散和反气旋环流；自东北南下经渤海回流到华北平原的空气是比较干的。该文分析结果有助于预报业务人员了解回流天气，提高华北回流天气的预报准确率。

The second part, composed of Chapter 4, 5 and 6, centers on the issues of the backflow of talents to rural areas who have received higher education.

第二部分由第4、5和6章构成。该部分围绕高等教育人才对农村的回流进行。其中，第4章主要分析了高等教育人才对农村的回流规模以及回流人才在地区之间的分布特征。

Backset current area, the important factor of burner performance was discussed on the basis of carrying on numerical simulation to the cement kiln with three-channel burner by the model of. RNG k-ε. The model that backset current area was divided into center backset current area, interior backset current area, and other backset current area was compared in three-dimensional condition.

在采用重整化群κ-ε模型对水泥窑用多通道燃烧器进行数值模拟的基础上，针对影响燃烧器性能的重要指标－回流区进行讨论，将三维条件下燃烧器的流场分布与传统燃烧器流场进行劝比，提出了三维条件下燃烧器回流区分为中心回流区、内回流区、外回流区3个回流区的分布模型，并分析了影响回流区的直流风和旋流风2个重要因素。

They are theory base of physical model and mathematical model.Secondly, we should start with Navier-Stokes equation and equation of continuity.

首先，通过丁坝回流理论和回流计算公式的探讨，分析丁坝回流产生的原因以及回流强度的影响因素，为物理模型和数学模型的建立提供理论基础。

In this article, firstly, the significance, features, conceptual development and implementary principles of recurrent education are expounded,and its economic value is illustrated in terms of its practicality and economic function; then the importance and properties of lifelong learning are analysed,and it is held that the distinguishment of and stress on recurrent education in the practice of lifelong education is the most essential and important means for the practical application of lifelong learning notions;lastly,the current situation of and obstacles to recurrent education are made clear and the implementary tactics and approaches are presented.

摘要］本文首先论述了回流教育的意义、特征、理念的发展以及实施原则，接着从回流教育的实用性及其经济功能来说明回流教育的经济价值；然后再论述终身学习的意义与特征，并从终身学习的实践途径中凸显回流教育的实施乃是实践终身学习理念最基础、最重要的途径。此外，文中也指明了目前实施回流教育的现况及阻力，提出了回流教育的实施策略与实施途径。

The experimental setup is designed to measure the change of dynamic holdup during the course of non-reflux period and the calculation value is consistent with the experimental results, which indicates that the downflow velocity of dynamic holdup becomes smaller with the decrease of dynamic holdup in the column during the course of non-reflux period.

本文设计了测定无回流过程中动持液量变化的实验装置，在与动态液相交换的全回流间歇精馏串联实验相同的条件下测定了无回流阶段的动持液量变化，模型计算值与实验值比较吻合，结果表明在无回流过程中随着精馏塔中动持液量越来越少，动持液向下流动速度也越来越小。

The ammonia was evaporated under decreasing pressure, and the precipitate was filtered off and the liquid was poured into hot saturated picric acid solution to get picrate with a yield of 85.0%. The optimum process starting from imidazole-4,5-dicarboxylic acid was: imidazole-4,5-dicarboxylic acid in acetic anhydride was refluxed to get imidazole-4-carboxylic acid, and the product was esterification in ethanol with a catalyzer of concentrated sulfuric acid to get ethyl imidazole-4-carboxylate, at last the compound above was reduced by LiAlH4 in ether at room temperature to get the target compound, the total yield of this route was 49.6%.

以4，5-二羧酸咪唑为原料的较佳工艺：1 脱羧反应：4，5-二羧酸咪唑40g，醋酐1200ml，回流10h，过滤并将滤液浓缩至干，所得固体加至50%的乙醇溶液回流，过滤并将滤液自然冷却过夜，过滤得固体；2 酯化反应：4(5)-羧酸咪唑50g，乙醇1000ml和浓硫酸60ml，加热回流2h，5%浓度NaOH溶液调节至pH＝8，减压浓缩至干，加入少量水回流，自然冷却过夜并过滤得固体；3 还原反应：LiAlH410g，乙醚300ml和4(5)-羧酸咪唑乙酯28g，常温反应1.5h，小心滴加25ml水后过滤，滤渣溶于300ml甲醇中并过滤，收集所得乙醚和甲醇滤液浓缩至干，将所得固体溶于300ml乙醇中加热回流，后将溶液浓缩至约30ml，冷却并过滤得固体，该路线总收率为49.6%。

Ingested feed is repeatedly ground and mixed in the gizzard, sent back to the proventriculus for more peptic juice application and returned to the gizzard.

第二种肠回流使食糜从十二指肠和空肠向胃区回流，这种回流在家禽体内大约每小时发生三次，但其发生频率随日粮脂肪增加而增加，随日粮纤维增加而减慢，肌胃内表面的典型银黄着色就是由于肠内食糜回流到肌胃而暴露于胆汁的证据。

Consulting the existed classified methods of rural surplus labor force and my understanding of circumfluence and non-return labor force, this article divides rural surplus labor force into two parts, which are native non-return rural surplus labor force and allochthonous non-return rural surplus labor force.

文章借鉴已有的农村剩余劳动力分类方法，并结合自己对回流与非回流劳动力的理解，将农村剩余劳动力分为两类，一类为异地非回流劳动力，一类为本地非回流劳动力。

Chapter 4 includes an overall analysis of the scale and regional distribution of the backflow and it is found that although the scale has been expanding, yet it is distributed disproportionably among different regions, specifically the East China occupying a comparatively larger percentage while the middle and west areas only a small proportion, and the unbalanced distribution has not changed much even after the reform in the tuition system and the implementation of Enrollment Expansion Policy.

分析结果表明，我国高等教育人才对农村的回流规模是不断扩大的，但是高等教育人才回流在地区之间的分布是不均衡的。东部地区占有了相对较多的回流人才，中西部地区较少。高等教育收费改革和扩招以后，人才对农村的回流率不断提高，回流规模继续扩大，但回流人才在地区之间的分布特征基本没有改变。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。