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目的:探讨机械通气(MV)在多脏器功能失常综合征(MODS)治疗中的效果。方法:对本中心近期收治的20例以咀嚼衰竭为主要表现的多脏器功能失常综合征病人,应用机械通气治疗的效果进行回顾性分析,结果:20例MODS中的呼吸衰竭应用MV治疗后,18例呼吸衰竭被纠正,结论:MODS中的呼吸衰竭应及早使用MV,有助于MODS的逆转 。 相似文献
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介绍Fe:KNbO3光折变晶体温度效应(290~380K)的实验研究,分别给出了在不同实验配置下的两波耦合和特殊切割晶体的自泵相位共轭的测量结果。 相似文献
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本文考虑了Banach空间中形如x(t)=u(t)∫atf(t,s,x(s)ds的广义Volterra积分方程,利用Monch不动点定理得到了所论方程解的某些存在定理。 相似文献
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一类非线性泛函边值问题的可解性 总被引:2,自引:0,他引:2
本文考虑非线性泛函边值问题,利用Borsuk定理与Leray-Schauder不动点定理,得到了上述边值问题的若干可解性结果。 相似文献
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为了研究降雨对空气中短寿命氡子体的清洗机制,设计了分别模拟大气降雨的水汽凝结过程和雨粒下降过程的两个实验装置,并进行了多次实验,实验水样采用低本底 能谱仪进行测量。实验结果表明:凝结水的短寿命放射性计数与本底相近,说明水汽凝结不能俘获短寿命氡子体。某一次自来水冲刷空气后获得了高出本底30.9% 的初始 计数,其半衰期为35.7 min,纯净水冲刷空气后获得了高出本底19.6%的初始计数,这些计数主要是由氡子体214Pb 和214Bi 引起的。可见,无论是自来水还是纯净水,它们冲刷空气后都能俘获短寿命氡子体,且半衰期和放射性核素种类均与雨水相似。这一实验结果充分说明:大气降雨的短寿命放射性不是在水汽凝结阶段而是在降落阶段对空气的冲刷获得的,是在降落过程中俘获了空气中的短寿命氡子体214Pb 和214Bi 而引起的。本次实验结果为降雨对空气中短寿命氡子体的冲刷清洗机制提供了最有力的证据。To investigate the underpinning mechanism of rainfall-scavenging of the atmospheric short-lived radon daughters, two experiments simulating water vapor condensing procedure and raindrop falling procedure were conducted. The radioactivity of the tested water was measured by low-background γ spectrometry. The obtained results showed that the γ-ray counts of condensed water was on the same level as the background,which proved that water vapor condensation cannot trap short-lived radon daughters. In contrast, the initial γ-ray count of washout water (35.7 min half-life) was increased by 30.9% after washing the atmosphere with tap water. Similarly, the initial -ray count of washout water was increased by 19.6% after washing the atmosphere with puri ed water. These counts originated mainly from radon daughters 214Pb and 214Bi. Obviously, both tap water and puri ed water can trap short-lived radon daughters when washing the atmosphere. Furthermore, the half-life and the kinds of radioactive nuclides in the washout water are similar to that in the rainfall water.These experimental results are able to ascertain that short-lived radon daughters in precipitation come mainly from scavenging (washout) and not from water vapor condensation within the cloud. It is in the process of falling that raindrops trapped short-lived radon daughters 214Pb and 214Bi. The obtained results as demonstrated here provide a powerful evidence for understanding the washout mechanism of short-lived radon daughters from theatmosphere by rainfall. 相似文献
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采用顶空-气相色谱法快速测定化工固体废物中16种挥发性有机物的含量。顶空加热平衡温度为80℃,顶空加热平衡时间为30min。用HP-FFAP色谱柱(30m×0.32mm,0.25μm)分离,氢火焰离子化检测器检测。16种挥发性有机物的的质量浓度在一定范围内与其对应的峰高呈线性关系,方法的检出限为0.001~0.009mg·L~(-1)。方法用于化工固体废物样品的分析,加标回收率为82.5%~115%,测定总量的相对标准偏差(n=6)为1.9%~9.1%。 相似文献
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