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- Thus it was demonstrated that the main pressure zone was little affected by the downstream flow condition. 由此可见，下游的流动情况对主要压力区几乎没有影响。
- REDUCED PRESSURE ZONE BACKFLOW PREVENTER For High Hazard Cross-connections and continuous pressure application. 减压区防回流阀用于高危险交叉连接和持续压力应用场合。
- The bypass line shall include a meter, small diameter reduced pressure zone assembly and isolation valves. 这个旁路管线应该包括一个水表，小直径减压区总成和隔离阀。
- For protection against backpressure backflow, install Watts 909/009 Reduced Pressure Zone Backflow Preventer. 如果要防止反压力回流，请安装美国瓦茨909/009减压区防回流阀。
- Used with Watts air gaps for vertical installation of Reduced Pressure Zone Assemblies. 当减压区总成垂直安装时,用于美国瓦茨气隙上。
- Series 909 Reduced Pressure Zone Assemblies are designed to provide crossconnection control protection of the potable water supply in accordance with national plumbing codes. 系列909减压区总成具有饮用水供应系统交叉连接管理功能，符合美国国家管道行业的有关规定。
- A negative pressure zone formed on the sidewall about 15 meters from the outlet. The aeration density at the sidewall was about 1.3%. 在侧墙有少量掺气;掺气浓度在1.;3%25左右;掺气的主要原因是侧墙冲击点处产生的立轴漩滚对空气的卷吸作用。
- Reduced Pressure Zone Assembly shall be installed at each potential health hazard location to prevent backsiphonage and/or backpressure backflow. 在每个具有潜在健康危害，需要防止反虹吸和/或反压力回流的地方应该安装一个减压区总成。
- Series 994 Reduced Pressure Zone Assemblies are designed to provide protection of the potable water supply in accordance with national codes. 系列994减压区总成适用于按照美国国家规程的要求保护饮用水供应系统。
- Series919 Reduced Pressure Zone Backflow Assemblies are designed to protect potable water supplies in accordance with national plumbing codes and water authority requirements. 系列919减压区防回流阀总成适用于保护饮用水供应系统，符合美国全国管道规程和水主管部门的要求。
- Series 009 Reduced Pressure Zone Assemblies are designed to protect potable water supplies in accordance with national plumbing codes and water authority requirements. 系列009减压区总成按照美国管道标准规程和水主管部门的要求保护饮用水供应系统。
- Reduced Pressure Zone Assembly shall be installed at each cross-connection to prevent backsiphonage and backpressure of hazardous materials into the potable water supply. 为了防止危险物质通过反虹吸和反压力进入饮用水供应系统，在每个交叉连接地方都应该安装一个减压区总成。
- Series 995 Reduced Pressure Zone Assemblies are designed to protect the potable water supply in accordance with national plumbing codes and water authority requirements. 系列995减压区总成适用于按照美国国家管道规程和水主管部门的要求保护饮用水供应系统。
- Reduced Pressure Zone Assembly shall be installed at each cross-connection to prevent backsiphonage and backpressure backflow of hazardous materials into the potable water supply. 在每个交叉连接的地方应该安装减压区总成，以防止危险物质反虹吸或反压力回流到饮用水供应系统中。
- This paper mainly discussed several methods used to decide microfissure, its distribution and reservoir-forming mechanism in abnormal pressure zone in mudstone. 主要论述了泥岩异常超压带内微裂隙的几种确定方法、分布及成藏机制的研究。
- Series 919 Reduced Pressure Zone Backflow Assemblies are designed to protect potable water supplies in accordance with national plumbing codes and water authority requirements. 系列919减压区防回流阀总成适用于保护饮用水供应系统，符合美国全国管道规程和水主管部门的要求。
- Reduced Pressure Zone Assembly shall be installed at each potential health hazard location to prevent backflow due to backsiphonage and/or backpressure. 在每个潜在健康危害的地方应该安装减压区总成，以防止由于反虹吸和/或反压力造成的回流。
- Reduced Pressure Zone Assemblies must be inspected and tested periodically, in accordance with local codes, to ensure proper operation of check valves within the unit. 减压区总成必须按照当地有关规定定期检查和测试,以确保这种装置内的止回阀能够正常运行。
- Backsiphonage protection shall include provision to admit air directly into the reduced pressure zone via a separate channel from the water discharge channel. 反虹吸保护应该包括使得空气通过与水排泄分离开来的渠道直接进入减压区的预防措施。
- Aiming at high permeability and low pressure zones, a cement slurry system with reinforced toughness and no water loss is developed. 针对大庆油田调整井高渗低压地层固井过程中易漏、水泥浆失水较大导致固井质量较差的问题,研究开发了增韧防漏水泥浆体系。
