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体外循环术后肺功能指标的比较及相关性分析 被引量:17
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作者 崔虎军 张明礼 +3 位作者 肖锋 李岩 王进 陈鸿义 《北京大学学报(医学版)》 CAS CSCD 北大核心 2003年第2期195-199,共5页
目的 :研究比较体外循环术后 3种肺功能指标的临床意义。方法 :选择在我院连续行择期体外循环下冠状动脉搭桥手术的 2 4例病人 ,根据体外循环停机后机血处理方式不同分为AT组 (血液回收组 )和非AT组 (非血液回收组 ) ,记录在麻醉诱导后... 目的 :研究比较体外循环术后 3种肺功能指标的临床意义。方法 :选择在我院连续行择期体外循环下冠状动脉搭桥手术的 2 4例病人 ,根据体外循环停机后机血处理方式不同分为AT组 (血液回收组 )和非AT组 (非血液回收组 ) ,记录在麻醉诱导后及停机后 1、6、2 4、4 8h的血流动力学和氧合指标 ,并计算比较呼吸指数 (RI)、氧合指数 (OI)和M指数 (PaO2 /PAO2 ) 3种肺功能指标。结果 :体外循环术后心脏指数 (CI)、氧摄取率 (O2ER)、氧利用指数 (DO2 I)和氧消耗指数 (VO2 I)均明显升高 ,而静动脉分流率 (Qs/Qt)呈逐渐降低趋势 ,两组间各指标没有差异。AT组中RI、OI和PaO2 /PAO2 在围手术期没有明显改变 ,而非AT组在停机后出现RI升高、OI和PaO2 /PAO2 降低 ,两组间没有统计学差异。但是非AT组停机 2 4h后RI和PaO2 /PAO2 的变化率与AT组有显著差异 ,改变趋势更明显。RI、OI和PaO2 /PAO2 三者均与Qs/Qt和VO2 I呈显著相关关系。结论 :RI、OI和PaO2 /PAO2 都恰当的反映了体外循环术后肺功能的变化 ,并且个体化的监测其动态变化可能对临床工作更具指导意义。 展开更多
关键词 体外循环 呼吸功能不全 自气/分析 冠状动脉旁路移植术 输血 自体
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Monitoring Ambient Air Quality in the Carpathian Region of Ukraine
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作者 Sergiy Kurta Ihor Mykytyn +1 位作者 Alexandra Voronych Viktoria Ribun 《Journal of Chemistry and Chemical Engineering》 2018年第1期31-37,共7页
Ivano-Frankivsk oblast is located in the south-western part of Ukraine, close to the geographical center of Europe at the junction of the two major geographic units, the East European Plain and the Eastern Carpathians... Ivano-Frankivsk oblast is located in the south-western part of Ukraine, close to the geographical center of Europe at the junction of the two major geographic units, the East European Plain and the Eastern Carpathians (the Carpathian region of Ukraine). Between September 2013 and September 2015, the expert group of the Department of Organic and Analytical Chemistry of Vasyl Stefanyk Precarpathian National University conducted the mobile monitoring of air cleanliness in Ivano-Frankivsk region; the authors monitored the level of air contamination with seven gases: carbon monoxide and dioxide, sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, formaldehyde, beta-particles, and gamma radiation. For this purpose, there were used six automatic analyzers "Dozor-C-P", the formaldehyde Gas Analyzer "MIC-98170", and the radiometer "TERRA". The monitoring resulted in the making of three maps of Ivano-Frankivsk region, on which the average levels of concentration of three particular gases (CO2, SO2, and CH20) throughout all the districts of the oblast were marked. There was registered the excess of CH20 limits--the consequences of the presence of the chipboard and wood-fiber production, for which formaldehyde is used as a raw material. Also there was observed the excess of SO2 in the air caused by gas fumes from vehicles and thermal power stations. 展开更多
关键词 MONITORING precarpathian air quality CONCENTRATION radiation air pollution MC (maximum concentration).
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An Assessment and Identification of Avalanche Hazard Sites in Uri Sector and its Surroundings on Himalayan Mountain
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作者 A.S.MOHAMMED Abdul Athick Hasan Raja NAQVI Zikra FIRDOUSE 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1499-1510,共12页
Avalanches are one of the most natural hazard in the mountain areas and therefore, identification of avalanche hazard is necessary for planning future development activities. The study area falls under the internation... Avalanches are one of the most natural hazard in the mountain areas and therefore, identification of avalanche hazard is necessary for planning future development activities. The study area falls under the international boundary region which generally covered by the snow(38%) on high altitude regions of the western part of Himalayas. Avalanches are triggered in study area during snowfall resulting in loss of human life, property and moreover the transportation and communication affected by the debris which ultimately delays the relief measures. Therefore in this study three major causative parameters i.e terrain, ground cover and meteorological have been incorporated for the identification of avalanche hazard zones(AHZ) by integrating Analytical Hierarchical Process(AHP) method in Geographical Information System(GIS). In the first part of study, avalanche sites have been identified by the criteria related to terrain(slope, aspect and curvature) and ground cover. Weights and ratings to these causative factors and their cumulative effects have been assigned on the basis of experience and knowledge of field. In the second part of the study, single point interpolation and Inverse Distance Weighted(IDW) method has been employed as only one weather station falls in study area. Accordingly, it has been performed to generate the meteorological parameter maps(viz. air temperature and relative humidity) from the field observatories and Automatic Weather Stations(AWS) located at Baaj OP in Uri sector. Finally, the meteorological parameter maps were superimposed on the terrain-based avalanche hazard thematic layers to identify the dynamic avalanche hazard sites. Conventional weighted approach and Analytical Hierarchical Process(AHP) method have been implemented for the identification of AHZ that shows approximately 55% area under maximum hazard zone. Further, the results were validated by overlapping the existing registered avalanche sites. The sites were identified through field survey and avalanche data card followed by its delineation from the toposheet(1:50,000 scale). Interestingly study found that 28% area under moderate and maximum AHZ correlated well with registered avalanche sites when they were overlapped. The accuracy for such works can be increased by field survey under favorable weather condition and by adding data from more number of AWS for predicting avalanche hazards in mountainous regions. 展开更多
关键词 Snow Digital Elevation Model(DEM) Meteorology Analytical Hierarchical Process(AHP) Avalanche hazard Uri sector
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Estimation on Global Reaction Heat for the Aromatization Process of Liquefied Petroleum Gas 被引量:1
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作者 黎小辉 朱建华 郝代军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第8期906-913,共8页
The reaction heat effect analysis for the aromatization process of Liquefied Petroleum Gas (LPG) was completed in this paper. In order to characterize this complex reaction system, one set of independent reactions was... The reaction heat effect analysis for the aromatization process of Liquefied Petroleum Gas (LPG) was completed in this paper. In order to characterize this complex reaction system, one set of independent reactions was determined by means of atomic coefficient matrix method. Based on reaction thermodynamic and stoichiometric knowledge, the heat effect, Gibbs free energy change and equilibrium constant for each independent reaction was calculated for the specified conditions. Under these conditions, based on the initial and final composition data from LPG aromatization experiments, the actual extent of reaction for each independent reaction was determined. Furthermore, the global reaction heat and adiabatic temperature rise of LPG aromatization reaction system could be estimated. This work would provide a theoretical guidance for the design and scale-up of reactor for LPG aromatization process, as well as for the selection of proper operating conditions. 展开更多
关键词 global reaction heat aromatization process liquefied petroleum gas
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Natural Attenuation and Biostimulation of Biodiesel Contaminated Soils from Southern Brazil with Different Particle Sizes
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作者 Liliane R.R. Meneghetti Antonio Thome +2 位作者 Femando Schnaid Pedro D.M. Prietto Gabriel Cavelhao 《Journal of Environmental Science and Engineering(B)》 2012年第2期155-162,共8页
Biodiesel bioremediation in soils may occur by natural attenuation or by engineered techniques, such as biostimulation and bioaugmentation. The present study evaluated the degradation of biodiesel in two soils with di... Biodiesel bioremediation in soils may occur by natural attenuation or by engineered techniques, such as biostimulation and bioaugmentation. The present study evaluated the degradation of biodiesel in two soils with different particle size characteristics by the bioremediation processes of natural attenuation and biostimulation. The experiment was carried out ex situ, with the factors temperature, moisture content, and pH being controlled for the experimental period of 110 days. The study aimed at evaluating the biodegradation of a clayey soil (A) and a sandy soil (B), both contaminated with pure biodiesel, by using the analytical methods of respirometry and gas chromatography. Biostimulation treatments using nitrogen, phosphorus, and potassium solutions (NPK) promoted higher microbiological activity in both soils. At the end of the experiment, it was observed that biostimulation was more efficient when compared to natural attenuation, showing higher biodiesel degradation for both soils A (59.76%) and B (90.41%). 展开更多
关键词 BIODEGRADATION COz evolution gas chromatography.
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A comparison of two kinds of eastward-moving mesoscale vortices during the mei-yu period of 2010 被引量:22
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作者 FU ShenMing YU Fei +1 位作者 WANG DongHai XIA RuDi 《Science China Earth Sciences》 SCIE EI CAS 2013年第2期282-300,共19页
During the mei-yu period,the east edge of the Tibetan Plateau and the Dabie Mountain are two main sources of eastward-moving mesoscale vortices along the mei-yu front(MYF).In this study,an eastward-moving southwest vo... During the mei-yu period,the east edge of the Tibetan Plateau and the Dabie Mountain are two main sources of eastward-moving mesoscale vortices along the mei-yu front(MYF).In this study,an eastward-moving southwest vortex(SWV) and an eastward-moving Dabie vortex(DBV) during the mei-yu period of 2010 have been investigated to clarify the main similarities and differences between them.The synoptic analyses reveal that the SWV and DBV were both located at the lower troposphere;however,the SWV developed in a "from top down" trend,whereas the DBV developed in an opposite way.There were obvious surface closed low centers corresponding to the DBV during its life span,whereas for the SWV,the closed low center only appeared at the mature stage.Cold and warm air intersected intensely after the formation of both the vortices,and the cold advection in the SWV case was stronger than that in the DBV case,whereas the warm advection in the DBV case was more intense than that in the SWV case.The Bay of Bengal and the South China Sea were main moisture sources for the SWV,whereas for the DBV,in addition to the above two moisture sources,the East China Sea was also an important moisture source.The vorticity budget indicates that the convergence was the most important common factor conducive to the formation,development,and maintenance of the SWV and DBV,whereas the conversion from the vertical vorticity to the horizontal one(tilting) was the most important common factor caused the dissipation of both of the vortices.The kinetic energy(KE) budget reveals that the KE generation by the rotational wind was the dominant factor for the enhancement of KE associated with the SWV,whereas for the DBV,the KE transport by the rotational wind was more important than the KE generation.The KE associated with the SWV and the DBV weakened with different mechanisms during the decaying stage.Furthermore,the characteristics of baroclinic and barotropic energy conversions during the life spans of both vortices indicate that the SWV and DBV both belong to the kind of subtropical mesoscale vortices. 展开更多
关键词 southwest vortex MEI-YU VORTICITY kinetic energy baroclinic energy conversion barotropic energy conversion
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A novel purification technique for noble gas isotope analyses of authigenic minerals 被引量:2
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作者 HE LiYan QIU HuaNing +3 位作者 SHI HeSheng ZHU JunZhang BAI XiuJuan YUN JianBing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第1期111-117,共7页
Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal ... Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system (PRC patent No. ZL201320117751.2), which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gas- es. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample (2082MS) which could not be cleaned up by the normal preparation system with two SAES NP10 getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system (OGRS) "Closed/Opened" in turn. When the OGRS is closed only with two NP10 getters for purification, the 40At intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about +2%-±1% (20-). When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ±0.4%. The OGRS is very helpful to obtain high-quality analysis data. 展开更多
关键词 40Ar/39Ar dating Gas purification technique Organic impurity Noble gas
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Solid wall effect on the transport coefficients of gases 被引量:2
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作者 FEI Fei FAN Jing JIANG JianZheng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第6期927-932,共6页
The diffusion,viscosity and thermal conductivity coefficients of gases between two parallel solid walls have been obtained analytically based on the Green-Kubo relation under a hard-sphere model.They decrease nonlinea... The diffusion,viscosity and thermal conductivity coefficients of gases between two parallel solid walls have been obtained analytically based on the Green-Kubo relation under a hard-sphere model.They decrease nonlinearly as the Knudsen number defined as the ratio of the mean free path to the wall distance increases.This theoretical prediction was in good agreement by the DSMC results. 展开更多
关键词 transport coefficient solid wall effect Green-Kubo relation Chapman-Enskog theory DSMC
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