基于示迹线方法的压气机内部流动显示试验

为了揭示压气机转子叶顶泄漏流和静叶吸力面分离流动的形态及演变趋势,采用示迹线显示空气流动的方法对某低速轴流压气机转子叶顶间隙流动及静叶吸力面复杂流动进行了直接观测。结果表明:转/静子叶片上的示迹线直观形象地显示了转子叶顶泄漏流动和静叶吸力面分离流动的形态及演变趋势;随着压气机节流,转子叶顶泄漏流抗衡主流的“力量”不断增强,导致叶顶泄漏流的影响区域不断向上游拓展,到达近失速工况时,泄漏流与主流的交界面与叶顶前缘平齐;随着压气机节流,静叶吸力面上的流动分离区不断向静叶前缘扩展,到达近失速工况时,50%叶高以下静叶吸力面一侧出现了大面积的回流区。

Meta-analysis of the efficacy and safety of rhbnp in the treatment of acute myocardial infarction with heart failure

Objective:Systematic review of the efficacy and safety of neoactivin re-acute myocardial infarction with heart failure.Methods:The computer retrieved CNKI,Wan Fang,Weipu Chinese Science and Technology Periodicals Database(VIP),China Biomedical Literature Database(CBM),Medline,Cochrane Library,and Clinical Trail.Gov collected clinical randomized controlled trials(RCTs)of neoactivin in the treatment of acute myocardial infarction with heart failure from the establishment of the database to December 2019.Data were extracted according to the Jadad scale,disease inclusion and exclusion criteria,and RevMan 5.3 software was used for Meta analysis.Results:A total of 23 RCTs were included,with a total of 2024 patients,including 1012 patients in the control group(conventional treatment with western medicine)and 1012 patients in the test group(on the basis of the control group+neoactivin treatment).Meta analysis results show that:in the total effective rate,the test group was better than the control group,and the difference was statistically significant(OR=4.30,95%CI[3.26,5.67],P<0.00001);In terms of left ventricular ejection fraction,the test group was better than the control group,and the difference was statistically significant(OR=1.58,95%CI[1.27,1.90],P<0.00001).In terms of the left ventricular end-diastolic diameter,the test group was better than the control group,with a statistical difference Significance(OR=-0.91,95%CI[-1.50,-0.33],P=0.002);In terms of stroke volume,the test group was better than the control group,and the difference was statistically significant(OR=1.24,95%CI[0.55,1.94],P=0.0005);In terms of brain natriuretic peptide precursors,the experimental group was better than the control group,the difference was statistically significant(OR=-4.37,95%CI[-6.21,-3.25],P<0.00001);In terms of heart rate,the test group was better than the control group,and the difference was statistically significant(OR=-13.70,95%CI[-14.95,-12.46],P<0.00001);In terms of systolic blood pressure,the test group was better than the control Group,the difference was statistically significant(OR=-12.38,95%CI[-17.98,-6.79],P<0.00001);In diastolic blood pressure,the test group was better than the control group Group,the difference was statistically significant(OR=-7.42,95%CI[-8.53,-6.30],P<0.00001);In terms of adverse reactions,the difference was not statistically significant(OR=0.95,95%CI[0.29,3.16],P=0.94).Conclusions:In patients with acute myocardial infarction and heart failure,the timely application of neoactivin treatment can improve clinical efficacy,improve cardiac function,inhibit ventricular remodeling,improve blood pressure and heart rate,which has good clinical efficacy and safety.

基于炉膛火焰发射光谱的煤种识别（英文）

目的:为解决煤种频繁变化造成的燃烧闭环优化难题,研究在燃烧器出口实时辨识锅炉入炉燃烧煤种的方法。创新点:1.通过火焰发射光谱机理研究获取可排除燃烧工况与测量采样等干扰因素的算法规则;2.提出基于煤粉火焰光谱中Na和K元素原子发射光谱相对强度特征的煤种辨识方法。方法:1.通过光纤光谱仪获取锅炉各层燃烧器入口火焰光谱信号;2.利用同波长下原子光谱与连续辐射光谱的相对关系,消去火焰温度、工况与环境的影响;3.以补偿后Na和K元素原子发射光谱强度的特征比值表征不同煤种在火焰中的元素含量特征,实现煤种的在线辨识。结论:1.利用煤粉火焰光谱特征实现入炉煤种的实时辨识具有良好的工况稳定性与可复现性;2.从算法机理中消除环境影响,降低了测量系统校验的复杂性。