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11.
Dr. Simon Pascal Léo Bucher Dr. Nicolas Desbois Dr. Christophe Bucher Dr. Chantal Andraud Prof. Dr. Claude P. Gros 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4971-4979
The synthesis of dyad and triad aza‐BODIPY‐porphyrin systems in two steps starting from an aryl‐substituted aza‐BODIPY chromophore is described. The properties of the resulting aza‐BODIPY‐porphyrin conjugates have been extensively investigated by means of electrochemistry, spectroelectrochemistry, and absorption/emission spectroscopy. Fluorescence measurements have revealed a dramatic loss of luminescence intensity, mainly due to competitive energy transfer and photoinduced electron transfer involving charge separation followed by recombination. 相似文献
12.
Very large nonlinear unconstrained binary optimization problems arise in a broad array of applications. Several exact or heuristic techniques have proved quite successful for solving many of these problems when the objective function is a quadratic polynomial. However, no similarly efficient methods are available for the higher degree case. Since high degree objectives are becoming increasingly important in certain application areas, such as computer vision, various techniques have been recently developed to reduce the general case to the quadratic one, at the cost of increasing the number of variables by introducing additional auxiliary variables. In this paper we initiate a systematic study of these quadratization approaches. We provide tight lower and upper bounds on the number of auxiliary variables needed in the worst-case for general objective functions, for bounded-degree functions, and for a restricted class of quadratizations. Our upper bounds are constructive, thus yielding new quadratization procedures. Finally, we completely characterize all “minimal” quadratizations of negative monomials. 相似文献
13.
Based on two artificial microstructures representing a long fiber reinforced thermoset material, the effective linear elastic material properties are calculated by both a mean and a full field homogenization method. Concerning the mean field method, the effective elastic material properties are approximated using the homogenization scheme by Mori and Tanaka, formulated explicitly in terms of orientation averages. This allows to use orienation tensors of 2nd and 4th order describing the orientation information on the micro level. The full field method is based on the fast Fourier transformation (FFT), for which the effective material properties are determined by volume averaging. The comparison between both methods show good agreements, the deviations are in the range between 2% and 12%. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
14.
Prof. Dr. Jean Christophe Tremblay Ambre Blanc Dr. Pascal Krause Sucharita Giri Prof. Gopal Dixit 《Chemphyschem》2023,24(2):e202200463
The present work focuses on probing ultrafast charge migration after symmetry-breaking excitation using ultrashort laser pulses. LiCN is chosen as prototypical system because it can be oriented in the laboratory frame and it possesses optically-accessible charge transfer states at low energies. The charge migration is simulated within the hybrid time-dependent density functional theory/configuration interaction framework. Time-resolved electronic current densities and simulated time-resolved x-ray diffraction signals are used to unravel the mechanism of charge migration. Our simulations demonstrate that specific choices of laser polarization lead to a control over the symmetry of the induced charge migration. Moreover, time-resolved x-ray diffraction signals are shown to encode transient symmetry reduction at intermediate times. 相似文献
15.
Depending on the solvothermal reaction conditions, we obtained three different metal-organic frameworks with yttrium(III) as metal component and 2,5-dihdyroxyterepthalic acid (H4dhtp) as bifunctional organic linker: Y2(H2dhtp)3(dmf)4 · (dmf)2 (CPO-29) contains dinuclear, paddle-wheel like inorganic secondary building units (SBUs) connected by the organic linker to a network with α-Po topology, while Y2(H2dhtp)(dhtp)(dmf)2 (CPO-30) and Y2(H2dhtp)(dhtp)(dmf)2(H2O)2 · (H2O)4 (CPO-31) contain one-dimensional inorganic SBUs that differ in how the half- and fully deprotonated ligands are connected to and arranged around them. Only the carboxylic acid groups of the organic linker are deprotonated in CPO-29, while CPO-30 and CPO-31 contain both 2,5-dihydroxyterephthalate (H2dhtp2–) linkers and fully deprotonated 2,5-dioxidoterephthalate (dhtp4–) linkers. All three compounds contain large volumes filled with solvent, but we were able to demonstrate permanence of porosity only for CPO-30. Variable temperature powder X-ray diffraction reveals that CPO-29 and CPO-31 undergo discontinuous phase transitions upon heating, and the flexibility of the framework structure indicated by these might be the reason for the inability to access the pore volume. Desolvated CPO-30 and CPO-31 are polymorphs, whose network structures differ in whether the H2dhtp2– and dhtp4– linkers are located in cis or trans arrangement around the inorganic SBU. 相似文献
16.
Baudat Emilie Gautier Céline Fichet Pascal Destrel Eric Colin Christèle Giuliani Margaux Lambrot Gabriel 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):637-650
Journal of Radioanalytical and Nuclear Chemistry - 90Sr radiochemical method using nitric acid for Sr and Ca separation was optimized using design of experiments methodology. Nitric acid... 相似文献
17.
Bruno Oyallon Marie Brachet-Botineau Cdric Log Thomas Robert Stphane Bach Sajida Ibrahim William Raoul Ccile Croix Pascal Berthelot Jean Guillon Noël Pinaud Fabrice Gouilleux Marie-Claude Viaud-Massuard Caroline Denevault-Sabourin 《Molecules (Basel, Switzerland)》2021,26(4)
Proviral integration site for Moloney murine leukemia virus (Pim)-1/2 kinase overexpression has been identified in a variety of hematologic (e.g., multiple myeloma or acute myeloid leukemia (AML)) and solid (e.g., colorectal carcinoma) tumors, playing a key role in cancer progression, metastasis, and drug resistance, and is linked to poor prognosis. These kinases are thus considered interesting targets in oncology. We report herein the design, synthesis, structure–activity relationships (SAR) and in vitro evaluations of new quinoxaline derivatives, acting as dual Pim1/2 inhibitors. Two lead compounds (5c and 5e) were then identified, as potent submicromolar Pim-1 and Pim-2 inhibitors. These molecules were also able to inhibit the growth of the two human cell lines, MV4-11 (AML) and HCT-116 (colorectal carcinoma), expressing high endogenous levels of Pim-1/2 kinases. 相似文献
18.
Pascal L. W. Welzen Sydney W. Martinez Ciriano Shoupeng Cao Alexander F. Mason Imke A. B. Welzen-Pijpers Jan C. M. van Hest 《Journal of polymer science. Part A, Polymer chemistry》2021,59(12):1241-1252
Polymersomes have gained much interest within the biomedical field as drug delivery systems due to their ability to transport and protect cargo from the harsh environment inside the body. For an improved drug efficacy, control over cargo release is however also an important factor to take into account. An often employed method is to incorporate pH sensitive groups in the vesicle membrane, which induce disassembly and content release when the particles have reached a target site in the body with the appropriate pH, such as the acidic microenvironment of tumor tissue or the endosome. In this paper, biodegradable poly(ethylene glycol)-poly(caprolactone-gradient-trimethylene carbonate)-based polymeric vesicles have been developed with disassembly features at mild acidic conditions. Modifying the polymer backbone with imidazole moieties results in vesicle disassembly upon protonation due to the lowered pH. Furthermore, upon increasing the pH efficient re-assembly into vesicles is observed due to the switchable amphiphilic nature of the polymer. When this re-assembly process is conducted in presence of cargo, enhanced encapsulation is achieved. Furthermore, the potency of the polymeric system for future biomedical applications such as adjuvant delivery is demonstrated. 相似文献
19.
Hippolyt L. Greve Marcel Kaiser Pascal Mser Thomas J. Schmidt 《Molecules (Basel, Switzerland)》2021,26(12)
In continuation of our search for leads from medicinal plants against protozoal pathogens, we detected antileishmanial activity in polar fractions of a dichloromethane extract from Boswellia serrata resin. 11-keto-β-boswellic acid (KBA) could be isolated from these fractions and was tested in vitro against Leishmania donovani axenic amastigotes along with five further boswellic acid derivatives. 3-O-acetyl-11-keto-β-boswellic acid (AKBA) showed the strongest activity with an IC50 value of 0.88 µM against axenic amastigotes but was inactive against intracellular amastigotes in murine macrophages 相似文献