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21.
A novel microwave-assisted synthesis of a library of triarylamides has been undertaken on the solid-phase.  相似文献   
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Ohne Zusammenfassung  相似文献   
25.

Background  

C57BL/6 mice show a relationship during aging between NMDA receptor expression and spatial reference memory performance in a 12-day task. The present study was designed to determine if age-related deficits could be detected with a shorter testing protocol and whether these deficits showed a relationship with NMDA receptors. Mice were trained in a reference memory task for two days in a Morris water maze. Cued testing was performed either after or prior to reference memory testing. Crude synaptosomes were prepared from prefrontal/frontal cortex and hippocampus of the mice that underwent reference memory testing first. NMDA receptor subunit and syntaxin proteins were analyzed with Western blotting.  相似文献   
26.
A four‐step synthesis of the PARP inhibitor 2‐(4‐trifluoromethylphenyl)benzimidazole‐4‐carboxamide (1, NU1077) is presented. Condensation of 2,3‐diaminotoluene and 4‐trifluoromethylbenzaldehyde afforded 4‐methyl‐2‐(4‐trifluoromethylphenyl)benzimidazole. Oxidation of the methyl group with potassium permanganate in warm t‐butanol afforded the carboxylic acid that was converted to the corresponding carboxamide via,/ the acid chloride.  相似文献   
27.
We discuss the unusual critical behavior of a generalized XY model containing both 2π-periodic and π-periodic couplings between sites, allowing for ordinary vortices and half-vortices. The phase diagram of this system includes both single-particle condensate and pair-condensate phases. Using a field theoretic formulation and worm algorithm Monte?Carlo simulations, we show that in two dimensions it is possible for the system to pass directly from the disordered (high temperature) phase to the single particle (quasi)condensate via an Ising transition, a situation reminiscent of the "deconfined criticality" scenario.  相似文献   
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A new super‐concentrated aqueous electrolyte is proposed by introducing a second lithium salt. The resultant ultra‐high concentration of 28 m led to more effective formation of a protective interphase on the anode along with further suppression of water activities at both anode and cathode surfaces. The improved electrochemical stability allows the use of TiO2 as the anode material, and a 2.5 V aqueous Li‐ion cell based on LiMn2O4 and carbon‐coated TiO2 delivered the unprecedented energy density of 100 Wh kg?1 for rechargeable aqueous Li‐ion cells, along with excellent cycling stability and high coulombic efficiency. It has been demonstrated that the introduction of a second salts into the “water‐in‐salt” electrolyte further pushed the energy densities of aqueous Li‐ion cells closer to those of the state‐of‐the‐art Li‐ion batteries.  相似文献   
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We have systematically investigated combinations of anions and cations in a number of protic ionic liquids based on alkylamines and used ab initio methods to gain insight into the parameters determining their liquid range and their conductivity. A simple, almost linear, relation of the experimentally determined melting temperature with the calculated volume of the anion forming the ionic liquid is found, whereas the dependence of the melting temperature with increasing cation volume goes through a minimum for relatively short side chain length. On the basis of the present results, we propose a strategy to predict the nature of protic ionic liquids in terms of low vapor pressure and conductivity. Comparisons with previously reported strategies for prediction of melting temperatures for aprotic ionic liquids are also made.  相似文献   
30.
A series of largely π-extended multichromophoric molecules including cross-conjugated, half cross-conjugated, conjugation-interrupted and linearly conjugated systems were synthesized and characterized. These multichromophoric molecular systems revealed interesting structural-property relationships. Bisporphyrin-fused pentacenes Pen-1 b and Pen-2 a showed rich redox chemistry with 7 and 8 observable redox states, respectively. The linearly-conjugated bisporphyrin-fused pentacenes ( Pen-1 b and Pen-2 a ) possess much narrower HOMO–LUMO gaps (1.65 and 1.42 eV redox, respectively) and higher HOMO energy levels than those of their pentacene analogues (2.23 and 2.01 eV redox, respectively), similar to those of much less stable hexacenes and heptacenes. An estimated half-life of >945 h was obtained for bisporphyrin-fused pentacene Pen-2 a , which is much longer than that of its pentacene analogue ( BPE-P , half-life, 33 h).  相似文献   
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