To problems of testing in heavy oil Wells, the improvement and completion of testing technology have been conducted by hydraulic nitrogen to control pressure difference.
针对稠油井测试工艺存在的问题，对稠油井测试工艺进行了改进和完善，认为用液氮可以控制压差。
Applying variable pressure difference control can reduce throttle loss and achieve better energy-saving effect.
采用变压差控制可减少阀门的节流损失，具有更好的节能效果。
Factors affecting constant pressure difference control method and advantages and disadvantages of the control plan are analyzed theoretically through pipe system head curve and pump performance curve.
根据管道水力特性曲线与水泵的性能曲线，运用理论分析的方法，对影响末端定压差控制方式的因素和该控制方案的利弊进行了分析。
The test result shows that by using bigger dimension difference of control hole A and B and high common-rail pressure the better open response of injector can be achieved.
试验结果表明较大的A、B量孔尺寸差值和高的共轨压力，可以获得较好的喷油器开启响应特性。
Performance experiments about ZY47 pressure -difference control valve and ZL47 flux control valve have been done, based on their structure and work principle, presented the method of type selection.
对ZY 47型自力式压差控制阀和ZL47型流量控制阀进行了性能实验，并依据它们的结构特点和工作原理，提出了选型方法。
Presents an idea of variable pressure difference control, and analyses the electric saving effect of this control mode.
提出采用变压差调控的思路，并对其进行了节电比较。
Results A significant difference was found in both blood pressure control and medical expense before and after the establishment of health records (P<0.01).
结果建档前、后血压控制情况及医疗费用情况间差异均有显著性意义（P<0·01）。
Working pressure is the hydraulic pressure control valve before the working hydraulic control valve back pressure minus the difference.
工作压差是指水力控制阀前的工作压力减去水力控制阀出口背压的差值。
Pulmonary heart disease group and COPD group, the control group of the right lower pulmonary diameter/pulmonary artery pressure value comparison, the difference was statistically significant.
肺心病组与COPD组、对照组组间的右下肺动脉直径/肺动脉压力值比较，差异均有统计学意义。
Results In comparison with control group, the intracranial pressure of mild hypothermia therapy has significant difference(P<0.05);
结果亚低温治疗前后颅内压差异有显著意义（P<0.05）；
Results In comparison with control group, the intracranial pressure of mild hypothermia therapy has significant difference(P<0.05);
结果亚低温治疗前后颅内压差异有显著意义（P<0.05）；
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