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The orthogonal experiments, which involves three factors: aeration intensity, suction time and suction suspended time, were designed to research membrane fouling of jet loop membrane bioreactor (JLMBR). Experimental results indicate that increasing aeration intensity, reducing suction time and increasing suction suspended time all could mitigate membrane fouling effectively. However excessive aeration intensity, too short suction time and excessive suction suspended time were bad for bioreactor running. The optimal aeration intensity, suction time and suction suspended time were 0.75 1.00 m3/(m2.h), 8 -10 min and 4 -5 min, respectively. The three factors all had effect on membrane pollution rate, while the suction time was the most important one and followed by aeration intensity and suction suspended time. It also indicates that, comparing with traditional submerged membrane bioreactors, JLMBR had lower membrane pollution rate. 相似文献
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“拇指文化”给高校大学生带来了正面和负面的影响。因此,必须辨证地分析这种文化现象背后的原因,全面探索“拇指文化”背景下高校思想政治工作的新发展,在宏观上积极营造健康向上的校园文化,中观上努力探索行之有效的思想政治工作途径和载体,微观上大力培养大学生自我教育与保护的意识和能力。 相似文献
86.
基于领域本体实现Web文本挖掘研究 总被引:1,自引:0,他引:1
87.
Jun-guo Yang Hai-ning Yu Shi-li Sun Lan-cui Zhang Guo-qing He Undurti N. Das Hui Ruan Sheng-rong Shen 《Journal of Zhejiang University. Science. B》2009,10(6):411-421
Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:l was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane,decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG. 相似文献
88.
He GQ Xiong HP Chen QH Ruan H Wang ZY Traoré L 《Journal of Zhejiang University. Science. B》2005,6(10):999-1004
Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations
of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at
50°C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids
(7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid
in hops.
Project (No. Y304203) supported by the Natural Science Foundation of Zhejiang Province, China 相似文献
89.
Objective: To observe the effects of fructose-1,6-diphosphate (FDP) on serum levels of cardiac troponin 1 (cTnl) and creatine kinase-MB (CK-MB), as well as the concentration of calcium in cardiomyocytes (Myo[Ca2 ]) and activity of sarcoplosnic Ca2 -ATPase (SRCa2 -ATPase) in Adriamycin (ADR)-treated rats. Methods: Rats were intraperitoneally injected with ADR (2.5 mg/kg every other day for 6 times) and then with different dosages of FDP (every other day for twenty-one times). Bi-antibodies sandwich Enzyme linked immune absorption assay (ELISA) was performed to detect serum level of cTnl. CK-MB was detected by monoclonal antibody, Myo[Ca2 ] was detected by fluorescent spectrophotometry and the activity of SRCa2 -ATPase was detected by inorganic phosphate method. Results: FDP (300, 600, 1200 mg/kg) significantly reduced the serum levels of cTnl and CK-MB, while at the same time decreased calcium concentration and increased SRCa2 -ATPase activity in cardiomyocytes of ADR-treated rats (P<0.01). Conclusions: FDP might alleviate the cardiotoxic effects induced by ADR through decreasing calcium level as well as increasing SRCa2 -ATPase activity in cardiomyocytes. 相似文献
90.
文章结合天津高职院校图书馆基于"馆藏揭示+开放获取"的专业性特色资源数据库建设实践,就如何分析、梳理、提炼、整合、存储基于学校专业建设的馆藏信息资源以及如何挖掘、整合和利用具有专业特色的开放获取文献信息资源进行了探讨,旨在探索一条适合高职院校的专业性特色资源建设之路。 相似文献