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111.
The method which we call the Weighted Averaging Based on Levels (WABL) can be used to calculate the average representative
of a fuzzy number. It utilizes weight coefficients for the level sets as well as the sides of a fuzzy number. We have developed
an algorithm to obtain these coefficients. The most remarkable feature of this algorithm is that it makes use of the decision
maker’s (DM) aggregation strategy. 相似文献
112.
Schniepp HC Shum HC Saville DA Aksay IA 《The journal of physical chemistry. B》2007,111(30):8708-8712
We demonstrate improved atomic force microscopic imaging of surfactant surface aggregates, featuring an increase in the topography contrast by several hundred percent with respect to all previous studies. Surfactant aggregates on rough gold surfaces, which could not be imaged previously because of low resolution, display substantially different morphologies when compared with atomically smooth materials. 相似文献
113.
Ku AY Saville DA Aksay IA 《Langmuir : the ACS journal of surfaces and colloids》2007,23(15):8156-8162
While exhibiting a well-defined nanometer-level structure, surfactant-templated nanoscopic silicas produced via self-assembly do not always possess long-range order. We demonstrate that long-range order can be controlled by guiding the self-assembly of nanostructured silica-surfactant hybrids with low-strength electric fields (E approximately 200 V/m) to produce nanoscopic silica with both the micrometer- and nanometer-level structures oriented parallel to the applied field. Under the influence of the electric field, nanoscopic silica particles migrate, elongate, and merge into fibers with a rate of migration proportional to the applied field strength. The linear dependence with the field strength indicates that the process is governed by electroosmotic flow but not by polarization effects. Realignment of the short-range ordered surfactant nanochannels along the fiber axis accompanies the migration. 相似文献
114.
Utility of the Pfitzinger Reaction in the Synthesis of Novel Quinoline Derivatives and Related Heterocycles
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Derviş Gök Rahmi Kasımoğulları Mustafa Cengiz Samet Mert 《Journal of heterocyclic chemistry》2014,51(1):224-232
2‐(2‐Amino‐3,5‐dinitrophenyl)‐2‐oxoacetic acid ( 2 ) was obtained from hydrolysis of 5,7‐dinitroisatin ( 1 ) in alkaline media. A novel quinoxaline derivative ( 3 ) was synthesized from the reaction of the same compound ( 1 ) with o‐phenylenediamine. Reacting 2 with ethyl 3‐oxo‐3‐phenylpropanoate yields 6,8‐dinitro‐2‐phenylquinoline‐3,4‐dicarboxylic acid ( 4 ). Then, 4 was converted into new quinoline‐diacylchloride, quinoline‐ester, quinoline‐dicarboxamide, pyridazine, and pyrroledione derivatives ( 5 , 6a , 6b , 6c , 6d , 7a , 7b , 7c , 7d , 8 , 9 , 10a , 10b , 10c , 10d , 11a , 11b , 12 ) with SOCl2, alcohols, amines, and hydrazines, respectively. The structures of synthesized compounds were clarified by 1H NMR, 13C NMR, IR, mass and elemental analysis methods. 相似文献
115.
Lionel RouxCédric Charrier Emmanuel SalomonMeral Ilhan Philippe Bisseret Céline Tarnus 《Tetrahedron letters》2011,52(20):2586-2589
Derivatives from the aminobenzosuberone family have been recently synthesized and recognized as highly selective inhibitors of aminopeptidase N (APN)/CD13 (EC 3.4.11.2), an important target for cell migration processes involved in particular in tumor invasion. We present here a much more straightforward synthesis of analogues belonging to a novel isosteric oxo series which also possesses excellent inhibitory potential against APN. Their synthesis, as reported here, relied on an interesting iodine(III)-mediated rearrangement originally described by Koser and Justik as the key step. This represents the second application of this rearrangement in medicinal chemistry. 相似文献
116.
The catalytic mechanism of a -dependent family 92 -mannosidase, which is abundantly present in human gut flora and malfunctions leading to the lysosomal storage disease α-mannosidosis, has been investigated using quantum mechanics/molecular mechanics and metadynamics methods. Computational efforts show that the enzyme follows a conformational itinerary of and the ion serves a dual purpose, as it not only distorts the sugar ring but also plays a crucial role in orchestrating the arrangement of catalytic residues. This orchestration, in turn, contributes to the facilitation of conformers for the ensuing reaction. This mechanistic insight is well-aligned with the experimental predictions of the catalytic pathway, and the computed energies are of the same order of magnitude as the experimental estimations. Hence, our results extend the mechanistic understanding of glycosidases. 相似文献
117.
We report herein a combined experimental–computational study on tris‐(2‐hydroxylethyl)methylammonium methylsulfate in water solutions, as a representative ionic liquid of the aqueous‐solution behavior of hydroxylammonium‐based ionic liquids. Relevant thermophysical properties were measured as a function of mixture composition and temperature. Classical molecular dynamics simulations were performed to infer microscopic structural features. The reported results for ionic liquid in water‐rich solutions show that it behaves as isolated non‐interacting ions solvated by water molecules, through well‐defined solvation shells, exerting a disrupting effect on the water hydrogen bonding network. Nevertheless, as ionic liquid concentration increase, interionic association increases, even for diluted water solutions, evolving from the typical behavior of strong electrolytes in solution toward large interacting structures. For ionic‐liquid‐rich mixtures, water exerts a minor disrupting effect on the fluid’s structuring because it occupies regions around each ion (developing water–ion hydrogen bonds) but without significantly weakening anion–cation interactions. 相似文献
118.
Augier de Cremiers H Clavier G Ilhan F Cooke G Rotello VM 《Chemical communications (Cambridge, England)》2001,(21):2232-2233
Polymer 4 and its monomeric counterpart 3 exhibit electrochemically tuneable interactions with anthracene polymer 2 and a structurally similar monomer 1 and seen by the variation of the oxidation waves of TTF groups and the fluorescence of the anthracene. 相似文献
119.
Çiğdem Çelen Ceren Keçeciler Mert Karış Bayram Göçmen Ozlem Yesil-Celiktas Ayşe Nalbantsoy 《Applied biochemistry and biotechnology》2018,186(2):350-357
Highly bioactive compounds of the snake venom make them particular sources for anticancer agent development. They contain very rich peptide-protein structures. Therefore, they are very susceptible to environmental conditions such as temperature, pH, and light. In this study, Vipera ammodytes transcaucasiana venom was encapsulated in PAMAM-G4 dendrimer by sol-gel method in order to prevent degradation of venom contents from the environmental conditions. For this purpose, nanoparticles were prepared by sol-gel methodology and SEM analyses were performed. U87MG and SHSY5Y neuronal cancer cell lines were treated with different concentrations of venom-containing nanoparticles and cytotoxicity was determined by MTT assay. IC50 values of nanoparticles with snake venom were calculated as 37.24 and 44.64 μg/ml for U87MG and SHSY5Y cells, respectively. The IC50 values of nanoparticles with snake venom were calculated as 10.07 and 7.9 μg/ml for U87MG and SHSY5Y cells, respectively. As a result, nanoparticles with V. a. transcaucasiana venom showed remarkably high cytotoxicity. Encapsulation efficiency of nanoparticles with 1 mg/ml snake venom was determined as %67 via BCA? protein analysis. In conclusion, this method is found to be convenient and useful for encapsulating snake venom as well as being suitable for drug delivery systems. 相似文献
120.
B. Kivcak T. Mert H. Saglam T. Ozturk M. Kurkcuoglu K. H. C. Baser 《Chemistry of Natural Compounds》2007,43(1):47-51
The chemical composition and antimicrobial activity of the essential oil from aerial parts of Anthemis wiedemanniana, an endemic taxon of Turkey, were investigated. Linalool (12.75%), 1,8-cineole (8.49%), hexadecanoic acid (6.09%), and chrysanthenone
(5.67%) were found to be the main components among the 122 compounds characterized in the essential oil of Anthemis wiedemanniana. Antimicrobial activities were reported against 12 microorganisms and five yeast-like fungi by the disc diffusion method.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–43, January–February, 2007. 相似文献