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981.
Ruthenium Complex “Light Switches” that are Selective for Different G‐Quadruplex Structures
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Erin Wachter Diego Moyá Dr. Sean Parkin Dr. Edith C. Glazer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):550-559
Recognition and regulation of G‐quadruplex nucleic acid structures is an important goal for the development of chemical tools and medicinal agents. The addition of a bromo‐substituent to the dipyridylphenazine (dppz) ligands in the photophysical “light switch”, [Ru(bpy)2dppz]2+, and the photochemical “light switch”, [Ru(bpy)2dmdppz]2+, creates compounds with increased selectivity for an intermolecular parallel G‐quadruplex and the mixed‐hybrid G‐quadruplex, respectively. When [Ru(bpy)2dppz‐Br]2+ and [Ru(bpy)2dmdppz‐Br]2+ are incubated with the G‐quadruplexes, they have a stabilizing effect on the DNA structures. Activation of [Ru(bpy)2dmdppz‐Br]2+ with light results in covalent adduct formation with the DNA. These complexes demonstrate that subtle chemical modifications of RuII complexes can alter G‐quadruplex selectivity, and could be useful for the rational design of in vivo G‐quadruplex probes. 相似文献
982.
Real‐Time Chemical Analysis of E‐Cigarette Aerosols By Means Of Secondary Electrospray Ionization Mass Spectrometry
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Dr. Diego García‐Gómez Dr. med. Thomas Gaisl César Barrios‐Collado Dr. Guillermo Vidal‐de‐Miguel Prof. Dr. med. Malcolm Kohler Prof. Dr. Renato Zenobi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2452-2457
Chemical analysis of aerosols collected from electronic cigarettes (ECs) has shown that these devices produce vapors that contain harmful and potentially harmful compounds. Conventional analytical methods used for the analysis of electronic cigarettes do not reflect the actual composition of the aerosols generated because they usually neglect the changes in the chemical composition that occur during the aerosol generation process and after collection. The aim of this work was to develop and apply a method for the real‐time analysis of electronic cigarette aerosols, based on the secondary electrospray ionization technique coupled to high‐resolution mass spectrometry, by mimicking the “vaping” process. Electronic cigarette aerosols were successfully analyzed and quantitative differences were found between the liquids and aerosols. Thanks to the high sensitivity shown by this method, more than 250 chemical substances were detected in the aerosols, some of them showing a high correlation with the operating power of the electronic cigarettes. The method also allows proper quantification of several chemical components such as alkaloids and flavor compounds. 相似文献
983.
Diego Montaño Isabel Bandrés Luz M. Ballesteros Carlos Lafuente Félix M. Royo 《Journal of solution chemistry》2011,40(7):1173-1186
In the present work we report experimental surface tensions for binary mixtures of isomeric chlorobutanes with methyl tert-butyl
ether from 283.15 to 303.15 K, measured with a drop volume tensiometer. From these experimental data the corresponding surface
tension deviations were calculated and correlated using a Redlich-Kister type polynomial. Finally, we include the calculation
of excess surface compositions for all of the mixtures from 288.15 K to 308.15 K. 相似文献
984.
Structural Chemistry - The adsorption of molecules on metal surfaces within confined spaces is key to industrially relevant processes such as catalytic conversions, separations, or gas storage.... 相似文献
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Diego Pecin Artur Pessoa Marcus Poggi Eduardo Uchoa 《Mathematical Programming Computation》2017,9(1):61-100
The best performing exact algorithms for the capacitated vehicle routing problem developed in the last 10 years are based in the combination of cut and column generation. Some authors only used cuts expressed over the variables of the original formulation, in order to keep the pricing subproblem relatively easy. Other authors could reduce the duality gaps by also using a restricted number of cuts over the master LP variables, stopping when the pricing becomes prohibitively hard. A particularly effective family of such cuts are the subset row cuts. This work introduces a technique for greatly reducing the impact on the pricing of these cuts, thus allowing much more cuts to be added. The newly proposed branch-cut-and-price algorithm also incorporates and combines for the first time (often in an improved way) several elements found in previous works, like route enumeration and strong branching. All the instances used for benchmarking exact algorithms, with up to 199 customers, were solved to optimality. Moreover, some larger instances with up to 360 customers, only considered before by heuristic methods, were solved too. 相似文献