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Stem Cells: MRI/SPECT/Fluorescent Tri‐Modal Probe for Evaluating the Homing and Therapeutic Efficacy of Transplanted Mesenchymal Stem Cells in a Rat Ischemic Stroke Model (Adv. Funct. Mater. 7/2015) 下载免费PDF全文
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Kailas L. Wasewar Diwakar Shende Amit Keshav 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(2):319-323
Itaconic acid finds a place in various industrial applications. It can be produced by biocultivation in a clean and environment friendly route but recovery of the acid from the dilute stream of the bioreactor is an economic problem. Reactive extraction is a promising method to recover carboxylic acid but suffers from toxicity problems of the diluent and extractant employed. So there is need for a non‐toxic extractant and diluent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. Effect of different extractants: tri‐n‐butylphosphate (TBP) (an organophosporous compound) and Aliquat 336 (a quaternary amine) in sunflower oil was studied to find the best extractant–sunflower oil combination. Equilibrium complexation constant, KE, values of 1.789 and 2.385 m3 kmol?1, respectively, were obtained for itaconic acid extraction using TBP and Aliquat 336 in sunflower oil. The problem of toxicity in reactive extraction can be reduced by using a natural non‐toxic diluent (sunflower oil) with the extractant. Copyright © 2010 Society of Chemical Industry 相似文献
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The mechanism of plastic forming and processing in electromagnetic dynamic tri‐screw extruder is very sophisticated and the investigation of amplitude–frequency characteristic acts as the foundation of equipment design and the optimization of polymer processing parameters. A mathematical and analytical model of plastic forming in such extruder was developed and the results were nondimensional‐normalized. To validate the mathematical solutions experiments based on LDPE were carried out and the experimental vibration amplitude and vibration frequency curve was obtained. Three conclusions can be drawn herein: (1) the experimental results hold a good agreement with the calculations, and thus the feasibility of the proposed model is validated; (2) the possibility of resonance closely relates to polymer melt viscosity, rotating speed, and geometry parameters of the screw; (3) resonance of the tri‐screw extruder is seldom observed under normal conditions and there exists an inverse correlationship between vibration frequency and amplitude. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122:1778–1784, 2011 相似文献
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Succinic acid has been pertracted with TOA using free liquid membranes without or with 1‐octanol. The addition of the alcohol led to the increase of up to 2.8–3 times of the acid's initial and final mass flows. At the same time, the influence of 1‐octanol on the transport capacity of the pertraction system was negative, its addition inducing the accumulation of succinic acid into the liquid membrane. A mathematical model describing the acid accumulation inside the liquid membrane has been developed for pertraction systems without and with 1‐octanol and offers good concordance with the experimental data. © 2012 Canadian Society for Chemical Engineering 相似文献
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EoC 技术是目前基于广电 HFC 网络实现三网融合的最佳接入技术之一,如何来评估及检测 EoC 产品的性能是本文主要解决的问题.本文以主芯片为 SPC -200C 的 HomePLUG BPL 方案 EoC 产品为测试基础,着重阐述了 EoC 产品的全方位性能测试新方法,以便能够为广电运营商提供一种 EoC 产品的测试及检测新手段. 相似文献
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The distribution of La, Pr, Nd, Eu, Gd and Tb nitrates between water and tributyl phosphate was investigated over a broad range of concentrations. It has been found that the distribution constant varies only slightly with the lanthanide atomic number, whereas the activity coefficients of the salts in concentrated organic solutions change considerably with both the lanthanide atomic number and concentration. Distribution ratios and separation factors for a number of binary mixtures were determined as a function of the composition at constant total concentration in each phase. 相似文献