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本文介绍了481-2B加氢精制催化剂的生产及应用。  相似文献   
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The multidrug transporter ABCB1 (MDR1, Pgp) plays an important role in the absorption, distribution, metabolism, and elimination of a wide range of pharmaceutical compounds. Functional investigation of the ABCB1 expression is also essential in many diseases, including drug-resistant cancer, inflammatory conditions, or Alzheimer disease. In this study, we examined the potential interaction of the ABCB1 multidrug transporter with a group of commercially available viability dyes that are generally considered not to penetrate into intact cells. Here, we demonstrate that the slow cellular accumulation of TO-PRO™-1 (TP1) or TO-PRO™-3 (TP3) was strongly inhibited by ABCB1-dependent dye extrusion. TP1/3 dye accumulation was not affected by the presence of ABCC1 or ABCG2, while this uptake was increased to the level in the ABCB1-negative cells by a specific P-glycoprotein inhibitor, Tariquidar. We suggest that TP compounds can be used as highly sensitive, selective, non-toxic, and stable dyes to examine the functional expression and properties of the ABCB1 multidrug transporter, especially in microplate-based high-throughput flow cytometry assays. In addition, we demonstrate the applicability of the TP dyes to efficiently select and separate even a very low number of Pgp-expressing intact cells.  相似文献   
3.
Interventional radiology procedures require extensive cognitive processing from the physician. A set of these cognitive functions are aimed to be replaced by technology in order to reduce the cognitive load. However, limited knowledge is available regarding mental processes in interventional radiology. This research focuses on identifying mental model–related processes, in particular during percutaneous procedures, useful to improve image guidance during interventions. Ethnographic studies and a prototype-based study were conducted in order to perform a task analysis and to identify working strategies and cognitive processes. Data were compared to theories from visual imagery. The results indicate a high level of complexity of mental model construction and manipulation, in particular when mentally comparing mental model knowledge with radiology images on screen (e.g., to steer a needle correctly). Regarding current interface support, most difficult is the interpretation and selection of oblique views. New interface principles are needed to bring cognitive demands within reasonable human range, and also accompanying cognitive work strategies should be developed.  相似文献   
4.
We report on the morphology evolution during heating and melting of lamellar poly(isoprene)-block-poly(ferrocenyldimethylsilane) (PI76-b-PFDMS76) raft crystals deposited at the native oxide surface of silicon (SiO2) or at a highly ordered pyrolytic graphite (HOPG) surface, studied by in situ temperature controlled atomic force microscopy. Crystals deposited on hydrophilic SiO2 surfaces revealed an irreversible decrease in length at temperatures of up to tens of degrees above their expected melting temperature, while maintaining their platelet-like structure. Crystals deposited on hydrophobic HOPG surfaces initially decreased in length below their expected melting temperature, while at 120 °C and above a typical molten morphology was observed. In addition, the irreversible formation of a PI76-b-PFDMS76 wetting layer around the crystals was observed upon increasing the temperature. These observations in the morphological behavior upon heating emphasize the role of interfacial energy between a surface deposited block copolymer based macromolecular nanostructure and its supporting substrate.  相似文献   
5.
高强度无溶剂单组分胶粘剂的制备及固化反应动力学研究   总被引:1,自引:0,他引:1  
以改性环氧树脂ES216和YAG80与增韧剂、活性稀释剂和固化剂制得性能优异的单组分无溶剂环氧树脂胶粘剂。利用差示扫描量热法(DSC)研究了胶粘剂的固化反应动力学,得到反应的活化能(Ea)、反应级数(n)、频率因子(A)及峰温时的反应速率常数(Kp)。  相似文献   
6.
控制棒水压驱动系统(CRHDS)是清华大学为NHR200发明的新型内置式控制棒驱动系统。组合阀是驱动系统关键的流量控制部件,其流动阻力对控制棒水压驱动机构的步进性能有重要影响。本文完成了驱动机构不同流动阻力工况步升过程性能试验,建立了驱动机构水压缸步升过程理论模型,得到了水压缸步升过程关键性能参数的动态变化曲线,理论结果与试验结果符合很好。在此基础上,利用模型分析了热态工况驱动机构水压缸变流阻步升动态过程。结果表明:随着流动阻力的增大,步升平均速度逐渐减小,步升时间、步升后压力迟滞时间和步升过程总时间均增大。研究成果为CRHDS组合阀流动阻力的设计和优化奠定基础。  相似文献   
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8.
在由岩心分析实验结果做出的油田开发期岩电相驱图的基础上 ,依据阿尔奇公式建立了利用侧钻井与套管井电阻率测井资料研究剩余油的方法。该方法已在南海东部西江油田生产中得到了应用。侧钻井与套管井电阻率测井资料的有效利用 ,可以在油田开发过程中快捷、方便地求出储层剩余油饱和度 ,进而求出油层衰竭指数 ,并据此对油层水淹程度及时作出评价 ,其用于随钻测井评价可以较大幅度地提高经济效益。  相似文献   
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10.
By exposing flat and curved carbon surfaces to coronene, a variety of van der Waals hybrid heterostructures are prepared, including coronene encapsulated in carbon nanotubes, and coronene and dicoronylene adsorbed on nanotubes or graphite via π–π interactions. The structure of the final product is determined by the temperature of the experiment and the curvature of the carbon surface. While at temperatures below and close to the sublimation point of coronene, nanotubes with suitable diameters are filled with single coronene molecules, at higher temperatures additional dimerization and oligomerization of coronene occurs on the surface of carbon nanotubes. The fact that dicoronylene and possible higher oligomers are formed at lower temperatures than expected for vapor‐phase polymerization indicates the active role of the carbon surface used primarily as template. Removal of adsorbed species from the nanotube surface is of utmost importance for reliable characterization of encapsulated molecules: it is demonstrated that the green fluorescence attributed previously to encapsulated coronene is instead caused by dicoronylene adsorbed on the surface which can be solubilized and removed using surfactants. After removing most of the adsorbed layer, a combination of Raman spectroscopy and transmission electron microscopy was employed to follow the transformation dynamics of coronene molecules inside nanotubes.  相似文献   
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