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排序方式: 共有441条查询结果,搜索用时 281 毫秒
61.
Teresa Ortega Elena De La Hera M. Emilia Carretero Pilar Gómez-Serranillos M. Victoria Naval Angel M. Villar Marin Prodanov Visitación Vacas Teresa Arroyo Teresa Hernández Isabel Estrella 《European Food Research and Technology》2008,227(6):1641-1650
Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols
constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo,
Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural
conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and
high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were
also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the
higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric
proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition
of wines relation with their vasorelaxation activity. 相似文献
62.
Prof. Amarajothi Dhakshinamoorthy Assoc. Prof. Sergio Navalón Prof. Abdullah M. Asiri Prof. Hermenegildo Garcia 《ChemMedChem》2020,15(23):2236-2256
Confinement of Au nanoparticles (NPs) within the porous materials with few nanometers (2-3 nm) has been a well established research area in the past decades in heterogeneous catalysis mainly due to the unique behaviour of Au NPs than its bulk counterpart. In this aspect, Au NPs encapsulated within the pore volumes of metal−organic frameworks (MOFs) have been intensively explored as heterogeneous solid catalysts for wide range of reactions. In recent years, Au NPs confined within the porous MOFs along with the photosensitizer or drug have been effectively used for the treatment of tumor cells through the generation of reactive oxygen species via cascade reactions. This work highlights the benefits of MOFs pores in the preparation of nanomedicine with high efficiency by assembling Au NPs, photosensitizer/drug with the combination of laser either for imaging or treatment of tumor cells. Further, the existing literature is grouped based on the nature of porous materials employed in the preparation of nanomedicine. The final section comments on our view on future developments in the field. 相似文献
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64.
混合轴承动特性简化计算方法 总被引:2,自引:2,他引:2
用一维流计算原理分析了多腔混合轴承的动态特性;计算了典型的毛细管节流四腔轴承在各种设计参数下的线性化刚度系数和阻尼系数,得到了轴承相应的刚度和稳定性速度阈值;比较了简化计算方法得到的数据与传统的雷诺方程数值解法得到的数据,且讨论了前者的误差影响。在常用工况条件下,其计算结果满足工程需要。 相似文献
65.
研究了Ti-Al-Fe低成本钛合金钨极氩弧焊焊接接头的内部质量、组织和力学性能,并与TC4钛合金进行了比较。结果表明,Ti-Al-Fe低成本钛合金焊缝表面质量良好,焊缝内部融合良好,无焊接缺陷,可焊性好; 2种合金的焊缝区宏观组织均由粗大的柱状晶和少量等轴晶组成,Ti-Al-Fe合金柱状晶组织较细,晶内由针状次生α相和少量的长条状初生α相组成; 2种合金热影响区均为粗大的等轴晶,晶内由大量初生α相和少量针状次生α相及残余β相组成; Ti-Al-Fe低成本钛合金焊缝抗拉强度达到1 204 MPa,比TC4钛合金高111 MPa。 相似文献
66.
辐射电磁场测试方法的研究 总被引:1,自引:0,他引:1
本文介绍了辐射电磁场检测装置的研制,该装置采用了多种屏蔽措施和计算机控制技术,提高了屏蔽室的隔离度,提高了控制精度、安全度及装置的自动化程度,具有我国特点,综合技术水平较先进。 相似文献
67.
Guo-liang Cao Guo-min Li Shan Chen Wan-shun Chang Xue-qun Chen College of Sciences Naval University of Engineering Wuhan China 《北京科技大学学报(英文版)》2011,(2):169-177
Nine steels with different deoxidizing degrees and two comparative steels were selected. Their pitting initiation susceptibility was compared by means of potentiodynamic polarization tests in 3wt% NaCl solution. The pit propagation rate was evaluated in artificial sea water and 3wt% sea salt solution by simulating occluded corrosion cell (SOCC) test and hanging plate test, respectively. The composition of inclusions and corrosive feature were studied by scanning electron microscopy (SEM), electron probe mic... 相似文献
68.
69.
Wigner-Ville时频分布在内燃机故障诊断中的应用 总被引:1,自引:2,他引:1
针对内燃机瞬时转速信号的非平稳性特点,将时频分布理论用于转速信号的故障特征提取。使用动力学仿真方法得到了正常状态和微弱单缸减油状态下的瞬时转速,对比计算它们的winger—Ville分布,发现时频分布图对功率不平衡性故障具有非常直观的可诊断性;这里winger-Ville分布的交叉项起到了放大微弱故障信息的作用,极大地提高了对故障的敏感程度,在仿真中可侦测单缸减油仅4%的模拟故障;使用实测的瞬时转速进行时频分布计算,经降噪处理后的时频分布图表现出了清晰的故障特征,证明是一种有效的基于瞬时转速故障特征提取的新方法。 相似文献
70.