回流

The experimental results show that the optimum conditions were as follows: molar ratio of pentaerythritol to phosphorus trichloride to bisphenol A was 1.0:2.8:2.0, the first and the second reaction held for about 3 h on the conditions of refluxing.

试验结果表明：反应溶剂为苯，用量为50 mL；物料配比〔m：m：m〕为1.0：2.8：2.0；第一步和第二步均回流反应3h。

To reveal aft end internal flow feature of a solid rocket motor with submerged nozzle, a two dimension cold flow test model with rectangular channel was designed The cold gas simulation was based on geometric similarity and aerodynamic analogy Mean and fluctuating velocity field was measured using phase doppler particle analyzer It showed that the flow separates at upstream of the submerged nozzle and reattaches on the tip of the nozzle nose A relatively steady recirculation zone formed in...

为了揭示含潜入喷管的固体火箭发动机尾部流动特征，按照几何相近和气动相似原则设计了通道为矩形的二维冷流实验模型，利用相位多普勒粒子分析仪对燃烧室尾部气流的时均速度和湍流脉动速度进行了测量。实验结果表明气流在潜入喷管入口上游发生分离，再附点位于喷管前端部外侧，背壁空腔内形成一个较为稳定的回流区，流场的轴向和横向湍流强度都比较大

The results show a reversed-flow region is formed at the tip of the pressure side due to the influence of the outside hot combustion gas and the pressure side tip thickness. The pressure gradient makes the coolant flow exit from the trailing edge slot first separates from the trailing edge cut-back, and then affected by the expansion wave, the coolant gas reattaches the cut-back of the trailing edge after passing a certain distance.

研究表明，由于外流和叶片叶盆尾缘厚度的影响，叶盆尾缘端部形成局部回流，叶片尾缘劈缝气体流出后受压力梯度的影响先抬起与叶背面分离，在流过一段距离后由于跨音速流膨胀波的作用，冷气流再次附着在叶背尾缘上。

In optimal design procedure, two important design variable are identified: one is recycle flow rate and the other is specification of acetic acid in the distillate of second column (pinch point exists between water-acetic acid system).

在最适设计步骤中，我们发现两个最重要的变数：回流股流量及第二根塔顶乙酸规格(乙酸与水之间有狭点存在)。

The following Test Procedure is one of several that is recognized throughout the United States for verification of the functioning of Backflow preventers.

下列检测程序是在美国广泛使用的防回流阀性能检测程序中的一种。

The following Test Procedure is one of several that is recognized throughout the United States for verification of the functioning of Backflow preventers.

下列检测程序是美国公认的几种防回流阀功能检测程序中的一种。

So when you need to be sure you have the most reliable residential containmentproducts, specify the Watts Series 7 backflow preventers.

所以，当用户需要确保使用的是最可靠的住宅防污染系统，则指定美国瓦茨系列7防回流阀。

The following Test Procedure is one of several that is recognized throughout the United States for verification of the functioning of Backflow preventers.

下列检测程序是美国公认的几种防回流阀功能检测程序之一。

The following Test Procedure is one of several that is recognized throughout the United States for verification of the functioning of Backflow preventers.

下列检测程序是美国通用的几种检测程序之一，用于检验防回流阀的功能。

The following Test Procedure is one of several that is recognized throughout the United States for verification of the functioning of backflow preventers.

下列检测程序是几种美国公认的防回流阀功能检测程序之一。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。