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21.
Berbeglia Gerardo Rayaprolu Gautam Vetta Adrian 《Annals of Operations Research》2019,274(1-2):131-154
Annals of Operations Research - We study the dynamic pricing problem faced by a monopolistic retailer who sells a storable product to forward-looking consumers. In this framework, the two major... 相似文献
22.
Antonella Battisti Silvio Panettieri Gerardo Abbandonato Emanuela Jacchetti Francesco Cardarelli Giovanni Signore Fabio Beltram Ranieri Bizzarri 《Analytical and bioanalytical chemistry》2013,405(19):6223-6233
The arsenal of fluorescent probes tailored to functional imaging of cells is rapidly growing and benefits from recent developments in imaging strategies. Here, we present a new molecular rotor, which displays strong absorption in the green region of the spectrum, very little solvatochromism, and strong emission sensitivity to local viscosity. The emission increase is paralleled by an increase in emission lifetime. Owing to its concentration-independent nature, fluorescence lifetime is particularly suitable to image environmental properties, such as viscosity, at the intracellular level. Accordingly, we demonstrate that intracellular viscosity measurements can be efficiently carried out by lifetime imaging with our probe and phasor analysis, an efficient method for measuring lifetime-related properties (e.g., bionalyte concentration or local physicochemical features) in living cells. Notably, we show that it is possible to monitor the partition of our probe into different intracellular regions/organelles and to follow mitochondrial de-energization upon oxidative stress. 相似文献
23.
A convenient synthesis of the cyclohexyl, (1R,3R,4S)-3-P-menthyl and (15-endo)-2-bomyl glyoxylates, from the respective alcohols and other very available materials, as a model applicable to that of other chiral, sensitive giyoxylates, is described. 相似文献
24.
Multiresidue method for the fast determination of pesticides in nutraceutical products (Camellia sinensis) by GC coupled to triple quadrupole MS 下载免费PDF全文
Gerardo Martínez‐Domínguez Patricia Plaza‐Bolaños Roberto Romero‐González Antonia Garrido Frenich 《Journal of separation science》2014,37(6):665-674
A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (Camellia sinensis). Extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean‐up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. Pesticide determination was achieved utilizing GC coupled to triple quadrupole MS/MS using the selective‐reaction monitoring mode. The total run time was 23 min. Pesticides were quantified using matrix‐matched calibration. Recoveries ranged from 70 to 120% and relative SD was lower than 25% at 10, 50, and 100 μg/kg. LOQs were lower than 10 μg/kg. 148 pesticides were validated. The validated method was applied to commercial nutraceutical products, detecting 4,4‐dichlorobenzophenone (28 μg/kg), o,p′‐dicofol (38 μg/kg) and p,p‐dicofol (44 μg/kg) in a few samples. 相似文献
25.
Dr. Ileana-Alexandra Pavel Dr. Gerardo Salinas Dr. Maciej Mierzwa Dr. Serena Arnaboldi Patrick Garrigue Prof. Alexander Kuhn 《Chemphyschem》2021,22(13):1321-1325
Numerous artificial micro- and nanomotors, as well as various swimmers have been inspired by living organisms that are able to move in a coordinated manner. Their cooperation has also gained a lot of attention because the resulting clusters are able to adapt to changes in their environment and to perform complex tasks. However, mimicking such a collective behavior remains a challenge. In the present work, magnesium microparticles are used as chemotactic swimmers with pronounced collective features, allowing the gradual formation of macroscopic agglomerates. The formed clusters act like a single swimmer able to follow pH gradients. This dynamic behavior can be used to spot localized corrosion events in a straightforward way. The autonomous docking of the swimmers to the corrosion site leads to the formation of a local protection layer, thus increasing corrosion resistance and triggering partial self-healing. 相似文献
26.
Gerardo Algara‐Siller Dr. Nikolai Severin Samantha Y. Chong Dr. Torbjörn Björkman Dr. Robert G. Palgrave Andrea Laybourn Prof. Dr. Markus Antonietti Prof. Yaroslav Z. Khimyak Dr. Arkady V. Krasheninnikov Prof. Dr. Jürgen P. Rabe Prof. Dr. Ute Kaiser Prof. Andrew I. Cooper Prof. Dr. Arne Thomas Dr. Michael J. Bojdys 《Angewandte Chemie (International ed. in English)》2014,53(29)
27.
Dr. Iryna Antonyshyn Dipl.-Eng. Ana M. Barrios Jiménez Dr. Olga Sichevych Dr. Ulrich Burkhardt Dr. Igor Veremchuk Dr. Marcus Schmidt Dr. Alim Ormeci Dr. Ioannis Spanos Dr. Andrey Tarasov Dr. Detre Teschner Dr. Gerardo Algara-Siller Prof. Dr. Robert Schlögl Prof. Yuri Grin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(38):16913-16919
28.
Gerardo Salinas Alice L. Dauphin Camille Colin Elena Villani Stphane Arbault Laurent Bouffier Alexander Kuhn 《Angewandte Chemie (International ed. in English)》2020,59(19):7508-7513
Miniaturized autonomous chemo‐electronic swimmers, based on the coupling of spontaneous oxidation and reduction reactions at the two poles of light‐emitting diodes (LEDs), are presented as chemotactic and magnetotactic devices. In homogeneous aqueous media, random motion caused by a bubble‐induced propulsion mechanism is observed. However, in an inhomogeneous environment, the self‐propelled devices exhibit positive chemotactic behavior, propelling themselves along a pH or ionic strength gradient (?pH and ?I, respectively) in order to reach a thermodynamically higher active state. In addition, the intrinsic permanent magnetic moment of the LED allows self‐orientation in the terrestrial magnetic field or following other external magnetic perturbations, which enables a directional motion control coupled with light emission. The interplay between chemotaxis and magnetotaxis allows fine‐tuning of the dynamic behavior of these swimmers. 相似文献
29.
Víctor G. Alfaro-García Anna M. Gil-Lafuente Gerardo G. Alfaro Calderón 《Computational & Mathematical Organization Theory》2017,23(3):391-408
In recent years, a trend for accelerating the economic, social and environmental development of cities through associations, organization and creation of synergies has been identified. Our investigation applies a grouping model in order to identify municipalities that could create optimal synergies towards the construction of competitive advantages. In order to achieve this task, we use tools of Fuzzy Logic to evaluate subjective and qualitative characteristic elements of different municipalities under Galois’ group theory. Results conclude on 32 different groups ordered in 7 different levels, relating 12 municipalities of a specific region according to 8 competitive variables. This work seeks to shed light in the conformation of groups under uncertain conditions and the deep examination of the characteristic competitive elements in a specific region for further policy and decision-making processes. 相似文献
30.
Gómez AM Danelón GO Pedregosa A Valverde S López JC 《Chemical communications (Cambridge, England)》2002,(18):2024-2025
Functionalized exo-glycals can be readily obtained by palladium catalyzed Suzuki cross-coupling of halo-exo-glycals with boronic acids. 相似文献