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991.
Bhawani Narayan Satyaprasad P. Senanayak Ankit Jain K. S. Narayan Subi J. George 《Advanced functional materials》2013,23(24):3053-3060
Oligo(p‐phenylenevinylenes) (OPVs) with amphiphilic character are synthesized and their self‐assembly characteristics studied. Careful studies point at two morphologically different states of assemblies, with one being two dimensional sheets and the other as rolled tubes. This is also the first time that self‐assembled sheets are achieved for OPVs. Morphological and photo‐physical studies reveal a unique aggregate to aggregate transition between rolled tubes and two dimensional sheets, which is outlined as a more thermodynamic aggregate. The thermodynamic aggregate (2D sheet) is better ordered and consists of chromophores that are better excitonically coupled. The mobilities of these aggregates are also studied for a field effect transistor device and as expected sheets supersede rolled tubes by a couple of orders. More interestingly, the mobility values obtained for the well ordered chromophores in sheets is three orders higher than any other self‐assembled OPV previously reported. It is hypothesized that the better π interactions enforced by the amphiphilic design and the resultant supramolecular organization is a prime factor for such a remarkable rise in mobilities. 相似文献
992.
A rate‐based mathematical model was developed for the reactive absorption of H2S in NaOH, with NaOCl or H2O2 as the chemical oxidant solutions in a packed column. A modified mass transfer coefficient in the gas phase was obtained by genetic algorithm and implemented in the model to correct the assumption of instantaneous reactions. The effects of different operating variables including the inlet H2S concentration, inlet gas mass flux, initial NaOH, concentrations of the chemical oxidants in the scrubbing solutions, and liquid‐to‐gas ratio on the H2S removal efficiency were studied. A genetic algorithm was employed to optimize the operating variables in order to obtain maximum removal efficiency of H2S. The model results were in good agreement with the experimental data. 相似文献
993.
994.
《Fusion Engineering and Design》2014,89(7-8):1309-1313
The experimental determination of mechanical and thermal properties of ceramic pebble beds, such as the lithium orthosilicate or lithium metatitanate, is a key issue in the framework of fusion power technology, for the reason that they are possible candidates in the design of breeder blankets.The paper deals with an experimental method for the evaluation of the thermal conductivity of ceramic pebble beds versus the temperature and compressive strain, based on a steady state heat flux through a material (alumina) of known conductivity. The alumina thermal conductivity is determined by means of the hot wire method. To assess the experimental method, a thermo-mechanical characterization of alumina pebble beds (a material largely available), having different diameters, considering a wide range of temperatures and compression forces has been carried out.Moreover preliminary tests have been performed on lithium orthosilicate and lithium metatitanate pebble beds. 相似文献
995.
Anna‐Lena Kjøniksen Maria Teresa Calejo Kaizheng Zhu Bo Nyström Sverre Arne Sande 《应用聚合物科学杂志》2014,131(13)
Several different polysaccharides have been added to pluronic F127 (poloxamer 407) gels to test their ability to stabilize the gels against dissolution in aqueous media over time. The studied polysaccharides include κ‐carrageenan, chitosan, hyaluronic acid, pectin, alginate, hydroxyethylcellulose, and ethyl(hydroxyethyl)cellulose. Although all the considered polysaccharides slowed down the dissolution time of the pluronic gels, unmodified polysaccharides only had a modest stabilization effect. However, hydrophobic modification of polysaccharides with a sufficiently long hydrocarbon chain (C16) was found to partly prevent the gels from dissolving for more than 6 months. Shorter hydrocarbon chains did not have the same effect, even at high degrees of hydrophobicity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40465. 相似文献
996.
997.
《Drug development and industrial pharmacy》2013,39(5):538-546
Local antimicrobial delivery is a potential area of research conceptualized to provide alternative and better methods of treatment for cases, as osteomyelitis where avascular zones prevent the delivery of drugs from conventional routes of administration. Drug-loaded polymers and calcium phosphates as hydroxyapatites have been tried earlier. Bioactive glasses are bone-filling materials used for space management in orthopedic and dental surgery. A new bioactive glass (SSS2) was synthesized and fabricated into porous scaffold with a view to provide prolonged local delivery of gatifloxacin and fluconazole as suitable for the treatment of osteomyelitis. The new SSS2 was characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses. In addition, the bioactivity of the SSS2 glass and resulting scaffold was examined by in vitro acellular method and ascertained by FTIR and XRD. The pore size distribution was analysed by mercury intrusion porosimetry and the release of drugs from scaffolds were studied in vitro. The glass and the resulting scaffolds were bioactive indicating that they can bond with bone in vivo. The scaffolds were porous with pores predominantly in the range of 10–60 µm, released the drugs effectively for 6 weeks and deemed suitable for local delivery of drugs to treat osteomyelitis. 相似文献
998.
UASB+MBR+NF处理焚烧垃圾渗滤液的设计及运行 总被引:1,自引:0,他引:1
介绍了UASB+MBR+NF工艺处理某垃圾焚烧厂渗滤液的工艺流程、构筑物设计参数及运行情况。运行结果表明,该工艺对垃圾渗滤液具有较高的去除率,COD、BOD5、NH3-N、SS的去除率分别高达99.84%、99.94%、99.28%、99.83%。处理后出水的各项指标可以达到《污水综合排放标准》(GB 8978—1996)中的一级排放标准。采用该工艺去除1 kg COD需要花费0.57元。与城市污水厂生活污水的运行费用相比,该工艺具有较好的经济性。 相似文献
999.
运用360°回旋自感应陶瓷焊补枪对玻璃窑炉小炉侧墙及平碹采用锆质陶瓷焊补料维修,并对维修前后做了对比分析。 相似文献
1000.
陶瓷业含酚废水的处理与酚的回收研究 总被引:1,自引:0,他引:1
采用先加入氢氧化钠反应,再进行蒸馏的方法,对陶瓷业含酚废水进行了处理及酚类物质回收的研究。探讨了氢氧化钠用量、搅拌时间以及蒸出液的体积对酚类物质去除和回收的影响。实验结果表明:对于25 mL的陶瓷业废水,氢氧化钠用量为0.9 g,搅拌10 min,蒸出液体积为15 mL,脱酚率高达96.44%,酚类物质回收率为95.12%。同时进行放大实验,脱酚率可达96.15%,酚类物质回收率仍高达94.96%,说明该方法处理陶瓷业水煤气废水的效果良好。 相似文献