suitable means shall be provided to prevent back flow of water into steam pipes in case there is any sudden drop in steam pressure.

适当是指应能达到防止水回流到蒸汽管内，导致任何的气压突然下降。

the test results show that the apron can reduce back flow at the dam toe, and the piers can obviously diminish river bed scouring near the scour resistant wall.

试验结果表明：护坦减轻了下游纵向围堰左侧坝趾处的回流淘刷，隔流墩明显减轻了防沖墻附近河床的沖刷，确保了坝基和下游纵向围堰的安全。

this paper simulates the effect of crosswind on the thermal performance of wet cooling tower and puts forward a feasibility advice of fixing back flow canal around the tower to reduce the water loss.

模拟了横向风对冷却塔热力特性和飘水损失的影响；提出了沿塔周设置回流槽的措施，以减少飘水损失。

what is the function of the back flow valve?

逆止阀的功能是什么？

the vertical partition board is reserved, which ensures that the advantage of the regenerating mode on back flow can be still exerted.

保留了竖向隔板，使回程式再生方式的优点仍可得以发挥。

in this paper, we present a new type of hybrid arc quenching system, which controls the metal vapor and back flow of the hot air in splitters arc quenching chamber.

本文研究了一种将窄缝与栅片配合应用于限流断路器的新型混合式灭弧系统。控制了栅片间金属短弧的金属蒸气喷流，同时削弱灭弧室中热气体的回流。

this pressure inversion can cause back flow of the process materials into the cylinder, or 「suck back」.

这种压力倒置会引起过程物质回流入钢瓶，或「吸回」。

the back flow effect of ooze-rock in toe-shooting method was analyzed. it concluded that the viscidity of ooze is a drag of motion of the ooze-rock all along;

本文对「填石排淤法」中的泥石回流效应进行了分析研究，其结果为淤泥的粘性始终起阻力的作用；

in this situation, dirty water from the hillside pool will back siphon or back flow down the hosepipe and into the clean water tank.

在这个情况，骯脏的水从山坡水池将后面或后面流程在下橡胶软管并且入干凈的储水箱。

using baicalin as the standard sample, the flavone substances in pollen of yunnan pine were determined through methyl alcohol back flow extraction and ultraviolet spectrophotometer.

以黄芩甙为标样，对云南松花粉中黄酮类化合物采用甲醇回流提取，用紫外分光光度法进行测定。

a flow control to install before back flow of the loop into the tank and to head the frequence control pump.

流速控制必须安装在循环系统中储罐的回水之前以控制变频泵。

the results show that by imposing static magnetic field, discharge velocity from the nozzle is suppressed, jet length is decreased, back flow zone in the center of the mold is reduced;

结果表明：在铸型宽度方向上施加的静态电磁场，不仅可以有效地抑制出水口的流速，减少其射流深度，还可以减小铸型中心处出现的回流区；

mitral back flow occurred 4 months after the operation and tricuspid back flow persisted after operation.

术后4个月出现二尖瓣反流，术后持续存在三尖瓣反流。

capacitance vessels constrict, increasing the back flow of venous blood.

容量血管收缩，静脉回流量增加。