提高心房除颤器治疗持续性房颤的可接受性:心房除颤器镇静评估研究(ADSAS)

Background: To compare the acceptability and effectiveness of three pre -medic ation regimens for manually activated cardioversion of recurrent persistent atri al fibrillation. Methods: Eighteen patients implanted with the Jewel AF atrial d efibrillator for drug-resistant persistent atrial fibrillation only were studie d in an open-labelled randomised crossover study. Patients were assigned to sed ation (S) with midazolam elixir, analgesia(A) with morphine sulphate or combinat ion therapy(C) with dextromoramide and lorazepam. Pre-medication was taken up t o 1h before cardioversion. Patients rotated through each type of medication afte r undertaking at least one cardioversion. Visual analogue scales were completed immediately post-cardiov-ersion and 24 h later for pain, anxiety and ‘unpleas an-tness’. Higher scores represented a worse outcome. Results: After 2 years’ follow-up, 238 cardioversions were performed with S, 17 with A and 35 with C. T he mean immediate combined score for S(10.9, 95%confidence interval(CI) 8.2-13 .6) was significantly lower than for A(17.3,95%CI 15.1-19.5,P=0.01)-and for C (15.9, 95%CI 12.3-19.6, P=0.02). All patients who used S chose it as the most favourable pre-medicant. All patients who used A found it the least acceptable . Conclusion: Sedation rather than analgesia enhanced the acceptability of manua lly activated atrial defibrillation.

高温高压CO2/原油界面张力及对驱油效率影响

在油藏温度下,采用ADSA(axisymmetric drop shape analysis)技术测定了不同压力下CO_2/原油动态界面张力和平衡界面张力。界面张力实验发现:原油与超临界CO_2接触的初始阶段存在强烈的扩散作用,原油中的轻质组分被超临界CO_2溶解抽提,并且随着压力的增加,这种溶解抽提作用增强;实验压力范围内,动态界面张力经过25~50 s左右可以达到一稳定值,当P≤19.998 MPa时,动态界面张力曲线波动较大,而当P≥19.998 MPa时,动态界面张力曲线基本保持不变。驱替实验结果表明:CO_2原油体系的平衡界面张力与气驱采收率之间存在关联关系:(1)随着压力升高,体系的平衡界面张力降低,气体突破时的驱油效率和气驱最终驱油效率升高;(2)压力增加到一定值后,体系平衡界面张力降低幅度减小,两种驱油效率增加的幅度也减小;(3)随着压力升高,气驱最终驱油效率与气体突破时的驱油效率之差增大。

BSA和SDBS在水溶液与空气界面的相互作用

The interaction between BSA (Bovine Serium Albumin)and SDBS (Sodium Do-decyl Benzene sulfonate) at water - air interface of aqueous solution was investigated byADSA(Axisymmetric Drop Shape Analysis) method. The surface tension responses to time weremeasured and compared. The results showed that (1) ADSA is a good methed to study the dy-namic change of surface tellsion to the time; (2) While SDBS concentration was less than its CMC,it could interact with BSA macro-molecule in the solution to form a complex which was moresurface active than both BSA and SDBS, and its conformation change in the adsorption layer wassimilar with that of BSA alone, (3) While SDBS concentration was larger than its CMC, its micellecould solubilize the BSA macro-molecule and the surface tension and the conformation change inthe adsorption layer was very similar with these of SDBS solution alone.

快速ADSA-P算法及用于超疏水材料接触角计算

为了确保超疏水材料静态接触角测量精度的同时提高计算速度，研究了水珠边缘点数对ADSA—P算法计算准确性和速度的影响。基于Young—Laplace方程在接触角在150°～179°，体积在1～100μL，点数为5—1001范围内产生了4158个水珠边缘，运用ADSA—P算法计算获得静态接触角。计算结果表明：大于临界点数时边缘点数对接触角计算准确性影响很小；小于临界点数时，随着点数的减少算法误差迅速增大；随点数增加算法计算速度逐渐下降。ADSA—P算法用于超疏水材料静态接触角计算时点数选择27即可，此时算法在保证准确性的同时，计算耗时少于原来的1／4。实测获得不同憎水性和体积的超疏水水珠图像并获得不同的边缘点数，ADSA—P算法的计算验证了以上分析结论。

Interfacial Tension of CO_2 and Organic Liquid under High Pressure and Temperature

In order to investigate the effect of organic liquid molecular structure and the intermolecular force operating with CO2 molecules and organic liquid molecules on interfacial tension(IFT) between CO2 and organic liquid at the first contact, the interfacial tension between CO2 and hexane, octane, ethanol and cyclohexane at different temperatures and pressures is measured by using the pendant drop method and the axisymmetric drop shape analysis(ADSA). The results show that the interfacial tension between CO2 and organic liquids is affected by the polarity and the structure of the organic liquid molecule obviously. The intermolecular force operating within CO2 molecules or organic liquid, and that between CO2 and organic liquids molecules play a dominate role on the interfacial tension between CO2 and the organic liquids.