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1.
采用自制的聚-4-甲基-1-戊烯中空纤维膜组装成中空纤维膜式人工肺组件,以去离子水、生理盐水、甘油水溶液和Na2SO3水溶液来模拟血液,按照中空纤维膜内通氧气、中空纤维膜外走模拟液的方式进行体外性能测试,测定膜式人工肺组件在不同的液体流速、气体压力、中空纤维膜根数和模拟液种类下的氧气传输速率.实验表明:随着液体流速的加快、气体压力的变大和中空纤维膜根数的增多,膜式人工肺组件在四种模拟液下的氧气传质性能均对应不同幅度的强化.同时,依据质量守恒定律和双膜理论建立了一种膜式人工肺组件的氧气传质数学模型,为中空纤维膜传质性能研究和人工肺组件的结构优化提供了有益的参考.  相似文献   

2.
人工肺是进行心脏直视手术和呼吸衰竭抢救中体外循环所必需的医疗器具,用以短期代替人肺功能. 我校材料科学研究所和上海市第一结核病防治院、上海第二医学院生物医学工程研究室合作研究成功的聚丙烯中空纤维膜式人工肺,被誉为国际上最新一代的人工肺.它是由一万根外径为250μm、壁厚为40μm的聚丙烯中空纤维丝组成.丝壁上有大量相互贯穿的栅状微孔,这种微孔不能透过水,但对气体有极高的透过率.使用时,血液在中  相似文献   

3.
中空纤维膜吸收过程多釜串联传质模型   总被引:1,自引:0,他引:1  
建立了一个可用于描述中空纤维壳程非理想流动的全混釜多级(多釜)串联传质模型,研究了中空纤维膜吸收器壳程非理想流动对其传质性能的影响,并对中空纤维膜吸收器的总传质系数进行了估算.模型预测与实验结果的比较表明,多釜串联传质模型可以较为准确地预测中空纤维膜吸收器的传质性能,有助于中空纤维膜吸收器的设计与优化.  相似文献   

4.
采用自制的聚丙烯中空纤维膜接触器脱除水中溶解氧,分别考察了水在中空纤维膜接触器的管程和壳程流动时,真空度、温度、进水流速以及中空纤维膜的有效长度对溶解氧脱除率的影响。实验结果表明:溶解氧脱除率随着系统真空度的增大而显著提高,在真空度为0.09MPa时,溶解氧脱除率可以达到80%以上;溶解氧脱除率随着流速的增加而增大,当流速达到一定数值之后,溶解氧脱除率保持不变;此外,溶解氧脱除率与中空纤维膜的有效长度密切相关.膜的有效长度越长.溶解氧脱除率越高,但其受进水温度并不明显。  相似文献   

5.
将聚偏氟乙烯(PVDF)中空纤维三液相微萃取与高效液相色谱法联用,建立了分离富集测定水样中吡虫啉的新方法.对聚偏氟乙烯中空纤维的种类、萃取剂、萃取时间等实验参数进行了优化,确立了以磷酸二氢钾溶液为接受相、聚偏氟乙烯中空纤维和正辛醇为介质的三液相微萃取,最佳条件下富集20mL样品溶液,用高效液相色谱法测定,吡虫啉的检测限为0.4ng·mL^-1,吡虫啉的富集倍数为22.75倍.该方法可用于水样中痕量吡虫啉的测定.  相似文献   

6.
利用聚丙烯(PP)中空纤维膜去除水中溶解氧的试验   总被引:1,自引:0,他引:1  
提出并研究了一个利用疏水性中空纤维膜去除水中溶解氧的新工艺 ,测定了所采用的聚丙烯 (PP)中空纤维膜的耐压性能。对促进除氧的机理进行了研究  相似文献   

7.
提出并研究了一个利用疏水性中空纤维膜去除水中溶解氧的新工艺,测定了所采用的聚丙烯(PP)中空纤维膜的耐压性能.对促进除氧的机理进行了研究  相似文献   

8.
从麻织物风格及其吸水性能的要求出发,探讨利用涤纶中空纤维设计纱线号数、混纺比,捻度的方法、提出当设计纱号为32s、混纺比80/20,设计捻度100.763捻/10cm时纺制的纱线可较好地体现中空涤纶纤维吸水性能好的特点。  相似文献   

9.
研究了湍流入料对线型中空纤维膜和编织型中空纤维膜的强化分离作用,比较了湍流入料与直流入料对线型中空纤维膜性能影响的差别,进行了迪恩涡强化编织型中空纤维膜与湍流入料强化线型中空纤维膜渗透性能的研究.试验结果显示,湍流入料能显著提高线型中空纤维膜渗透性能,减少浓差极化和膜污染,回收率增大2倍,能耗低20%以上;湍流入料可增大编织型中空纤维膜渗透流量10%左右,能耗降低5%左右,膜组件长度越短,效果越明显迪恩涡强化编织型中空纤维膜分离性能优于湍流入料强化线型中空纤维膜分离性能,能耗低20%以上,渗透回收率高1~1.5倍.图6,参8.  相似文献   

10.
基于Maxwell方程,构建中空电磁纤维的电磁模型,分析电磁波与中空电磁纤维的相互作用,推导中空电磁纤维的轴向磁导率、轴向介电常数及径向磁导率与径向介电常数这些典型电磁参量的理论公式,从而证实中空电磁纤维的电磁参量具有强各向异性;以Fe纤维为例,通过对频率5 GHz的各向异性复磁导率和复介电常数的数值计算,发现轴向电磁参量是影响纤维微波电磁性能的主要因素,且中空纤维应用于微波吸收比实心纤维具有更好的电磁匹配性和电磁损耗性能.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
19.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

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