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71.
Shakeel Sadia Gul Somia Zahoor Aqib Khan Saleha Suleman Sheikh Zeeshan Ahmed Naveed Safila Usmanghani Khan 《平面色谱法杂志一现代薄层色谱法》2015,28(5):386-390
JPC – Journal of Planar Chromatography – Modern TLC - The technological improvement in the structural elucidation of natural compounds has made it probable to generate appropriate... 相似文献
72.
Reyhan Sengur-Tasdemir Sevcan Aydin Turker Turken Esra Ates Genceli 《Separation & Purification Reviews》2016,45(2):122-140
Membrane technology is the dominant process in water treatment. However, the operation cost of membranes cannot be decreased unless the amount of fouling, the “Achilles heel” of membranes, and energy consumed are cut. The high energy requirements in commercial nanofiltration, reverse osmosis and forward osmosis technologies lead researchers to develop new membrane designs having high flux values with high salt rejection values. The purpose of this review is to present the inadequacies of the membrane processes by considering studies related to fouling and energy minimization. In this respect, lipid bilayers, block copolymers, aquaporin Z proteins and aligned carbon nanotubes can be the base to build biomimetic membranes. Such studies are summarized due to their remarkable properties in fouling control. Furthermore, the review describes the membrane design strategies and points the limitations hindering commercialization. Additionally, it is hoped that this review will trigger further needed studies. 相似文献
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74.
Aytac Guven 《国际流体数值方法杂志》2011,66(11):1371-1382
In this study, support vector machine (SVM) is proposed as a new predictive model for pressure fluctuations beneath free jump occurring on sloping channels. The proposed model reproduces the pressure fluctuation intensity C′p in terms of normalized flow and channel section characteristics. The model variables were derived from dimensional analysis. The proposed model is calibrated and validated by using a wide range of experimental data. The SVM predicted C′p with a correlation of coefficient (CC) of 0.989 and a root mean square error (RMSE) of 0.004. Also, linear and nonlinear regression analyses are applied on the same experimental data set, and the SVM model is compared to the equations obtained from these regression analyses. CC, RMSE and average absolute deviation (Di) are used in the evaluation of performance of each model. The SVM model predicted the measured pressure fluctuations better than conventional regression equations. The results of this study reveal that the proposed SVM model can be effectively used in predicting the pressure fluctuation beneath free jump. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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76.
Reyhan BastinJames W. Dale Michael G. EdwardsJulien P.N. Papillon Michael R. WebbRichard J.K. Taylor 《Tetrahedron》2011,67(51):10026-10044
A formal synthesis of neooxazolomycin is described via the preparation of Kende’s key intermediate in a longest linear sequence of 23 steps. This work is founded upon the union of three fragments: Moloney’s lactam-derived triflate, a vinyl stannane and a Julia-Kocienski sulfone and encompasses three key steps: (i) a Stille cross-coupling to combine the triflate and vinyl stannane, (ii) a base-promoted enone deconjugation to derive the dihydroxylation precursor and (iii) our previously reported Julia-Kocienski methodology to assemble the pentadienyl amine side chain with the sulfone precursor. 相似文献
77.
Tabassum Shaheera Zahoor Ameer Fawad Ahmad Sajjad Noreen Razia Khan Samreen Gul Ahmad Hamad 《Molecular diversity》2022,26(1):647-689
Molecular Diversity - Cross-coupling reactions are powerful synthetic tools for the formation of remarkable building blocks of many naturally occurring molecules, polymers and biologically active... 相似文献
78.
Sakhabutdinova Gul’nur N. Raskil’dina Gul’nara Z. Baikova Irina P. Zlotskii Simon S. Sultanova Rimma M. 《Chemistry of Heterocyclic Compounds》2019,55(12):1222-1227
Chemistry of Heterocyclic Compounds - The reaction of substituted 1,3-oxathiolanes with diazocarbonyl compounds in the presence of Cu(OTf)2 and Rh2(OAc)4 was studied. The reaction is accompanied by... 相似文献
79.
R. Trencsényi Z. Gulácsi 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,75(4):511-525
Describing by a Hubbard type of model a thin armchair graphene ribbon in the armchair hexagon chain limit, one shows in exact
terms, that even if the system does not have flat bands at all, at low concentration a mesoscopic sample can have ferromagnetic
ground state, being metallic in the same time. The mechanism is connected to a common effect of correlations and confinement. 相似文献
80.