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1.
Different top layer fabrication methods (amine-first, acid-first, spin coating), organic phase solvents (hexane, heptane, mixed hexane/heptane), acid acceptors (triethylamine, sodium carbonate, sodium hydroxide), and surfactant sodium dodecyl sulfate concentrations (0, 0.05, and 0.1 wt%) were utilized to fabricate thin film composite polyamide membranes for CO2/N2 separation. The results, according to an L9 orthogonal array of Taguchi approach, showed that employing acid-first method increases both CO2 permeance and CO2/N2 selectivity of the membranes at a feed gas pressure of 3 bars. On the other hand, sodium hydroxide, and triethylamine should be used, as acid acceptors, to maximize CO2 permeance and CO2/N2 selectivity, respectively. Moreover, the use of hexane solvent and 0 wt% surfactant led to maximum permeance, while, hexane solvent and 0.1 wt% surfactant were needed to reach the highest selectivity. The above level setting of synthesis parameters also resulted in the minimum sensitivity of the fabrication process to the noise factors effects. As shown by the analysis of variance, acid acceptor, and organic solvent types were the most influential parameters on CO2 permeance and CO2/N2 selectivity, respectively. The effects of fabrication method and surfactant concentration, as single factors, on permeation/selectivity responses were also investigated. 相似文献
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Rezvan Tavakoli Saeid Vakilian Fatemeh Jamshidi-Adegani Samaneh Sharif Abdolreza Ardeshirylajimi 《国际聚合物材料杂志》2018,67(15):873-878
In situ prolonged delivery of drugs at the site of tumor can be satisfactorily accelerated patient recovery. We compared the effect of temozolomide while incorporated by polycaprolactone nanofibers on the apoptotic behavior of U87 glioma cells. After biocompatibility evaluation of nanofibers by scanning electron microscope and 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide analysis, the apoptosis of U87 cells was evaluated using p53, Bcl2 and Bax genes expression. It was found that nanofiber-temozolomide group showed a greater ability to induce apoptosis as well as have a significantly diminished initial burst release of drug compared with other groups and have promising potential in treating cancer. 相似文献
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Ahlam Ammar Sharif 《建筑学研究前沿(英文版)》2020,9(4):837-857
Urban researchers have maintained a constant interest in the complexity and continuity of urban space usage. Some have applied actor–network theory (ANT) to investigate the heterogeneity of spaces and present them through the networks of their users’ activities. However, these accounts are predominantly limited in examining the extent to which these spaces may be heterogeneous when exploring such networks. This paper draws on recent ANT scholarship, which employs an ethnographic research conducted in a main park in a housing project at Dahiyat Al Hussein in Amman, Jordan. The findings describe the complex and unpredictable negotiations that occur within spaces by documenting the varieties and interrelations among user activity networks within this common and shared urban space. This research reveals the extent to which spaces, parks in this case, may be heterogeneous by unpacking their usage. The conclusions and insights assert the necessity of paying attention to design detail and creating designs that are responsive to evolving user activities. 相似文献
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Sandra Appelt Sharif S. Aly Karen Tonooka Kathy Glenn Zhengyao Xue Terry W. Lehenbauer Maria L. Marco 《Journal of dairy science》2019,102(3):1985-1996
Bovine mastitis is an economic burden for dairies worldwide. Mycoplasma species, and especially Mycoplasma bovis, are among the most important causative agents, and rapid, precise, and low-cost methods for Mycoplasma detection are urgently needed. For this purpose, loop-mediated isothermal amplification (LAMP) and quantitative PCR (qPCR) assays were developed and compared. The LAMP assay was designed and primer concentrations optimized to M. bovis oppD, encoding oligopeptide permease D. For qPCR, a Taqman assay (Applied Biosystems, Carlsbad, CA) targeting M. bovis gltX, encoding glutamate transfer RNA ligase, was optimized for primer concentration, annealing temperature, and DNA polymerase. Both assays were similarly sensitive, with a detection limit of approximately 104 to 105 M. bovis cells/mL. Both assays were also successful in confirming M. bovis identity in laboratory culture suspensions and in bovine milk. The LAMP and qPCR assays combined with the MoBio DNA extraction kit (MoBio Laboratories Inc., Carlsbad, CA) resulted in the correct detection of 13 out of 13 M. bovis isolates and 14 out of 16 M. bovis-positive milk samples collected from commercial dairies in California. When combined with the PrepMan Ultra reagent (Applied Biosystems), the qPCR assay resulted in confirming 21 out of 21 M. bovis-positive milk samples. Comparison of the assays to milk containing either Mycoplasma arginini, Mycoplasma bovigenitalium, Mycoplasma californicum, M. alkalescens, or Acholeplasma laidlawii or milk lacking any detectable Mycoplasma species or relatives resulted in 3 out of 17 (LAMP with MoBio), 1 out of 17 (qPCR with MoBio), and 2 out of 36 (qPCR with PrepMan Ultra) false positives. Overall, the qPCR assay was more robust than LAMP and could be used on DNA recovered from milk prepared with the PrepMan Ultra reagent, a method that does not include a DNA purification step. The use of this qPCR method enables M. bovis detection in bovine milk in 40 to 55 min, and therefore provides new opportunities to accelerate and simplify M. bovis detection in unpasteurized milk to reduce the incidence of M. bovis mastitis outbreaks. 相似文献
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Yara Sharif 《Landscape Research》2019,44(7):872-891
ABSTRACTThis paper sheds a light on the ephemeral landscape of Palestine. Under a deliberate process of ‘erasing, peeling, cutting and pasting’, the physical and mental maps of Palestine today are rapidly changing with the Palestinians being pushed out of the scene. This colonial project has been best represented by Sari Hanafi as ‘spacio-cidal’ as it targets the landscape and consequently the narrative of those who shape it.Stemming from the need for an alternative discourse to narrate and redraw the map from a local lens, I use the village of Beit Iksa as an example to portray the spatial restructuring of the landscape. I show how ‘greening’ casts a shadow on the Israeli colonial strategies that lie beneath to alienate and ‘reinvent’ the rural scene. And yet, because for every strategy of control there is a tactic to resist, I show how through spatial interventions, I tried to rethink the rural and challenge its ideological transformation into a void; a leftover landscape shaped by time and immobility and yet is loaded with spatial potentials and open to change. 相似文献
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Mohammad Mazaheri Yousef S. Kavian Hamid Sharif Habib F. Rashvand 《Wireless Communications and Mobile Computing》2016,16(15):2406-2418
Because of the practical limitations of the energy and processing capabilities, the deployment of many Wireless Sensor Networks (WSN) is facing two main challenges of increasing network lifetime and reducing End to End Delay (EED) which become critical when the nodes are mobile and use non‐rechargeable energy sources. One way to help to extend network lifetime is using fuzzy logic in a form of artificial intelligence. To this end we propose a new routing protocol for using mobile WSNs, which holds the nodes in an equal level of energy and decreases energy dissipation of the network. An optimum path is selected based on the cost of each node to increase network lifetime. In order to lessen EED, we also attempt to design a novel zoning‐scheme for the network area. In this scheme, zonation is dynamic and works based on the Data Link (DL) position. The simulation result shows a significant improvement in lifetime and EED by proposed protocol compared with existing protocols. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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