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991.
992.
Federica Valentini Giulia Brufani Benedetta Di Erasmo Luigi Vaccaro 《Current Opinion in Green and Sustainable Chemistry》2022
The great challenge for modern research is to define the most efficient tools to make more sustainable the industrial production and manufacturing. Among the different aspects that require attention the replacement of toxic and/or non-renewable solvents it is certainly playing a crucial role. Dealing with widely used dipolar aprotic solvents, among the different alternatives proposed in the literature γ-valerolactone (GVL) plays a pivotal role covering different application area. In this contribution, the benefits derived from the use of GVL as a circular, safe, biomass-derived reaction medium are highlighted covering most recent publications (2021). The presentation has been divided into three major sections: (i) biomass valorization, (ii) materials synthesis, manufacturing and recycle and (iii) new synthetic methodologies. 相似文献
993.
Study of spatial inhomogeneity in inverted all‐polymer solar cells: Effect of solvent and annealing
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Andrea Perulli Sandro Lattante Anna Persano Adriano Cola Massimo Di Giulio Marco Anni 《Journal of Polymer Science.Polymer Physics》2015,53(11):804-813
The efficiency optimization of bulk heterojunction solar cells requires the control of the local active materials arrangement in order to obtain the best compromise between efficient charge generation and charge collection. Here, we investigate the large scale (10–100 μm) inhomogeneity of the photoluminescence (PL) and the external quantum efficiency (EQE) in inverted all‐polymer solar cells (APSC) with regioregular poly(3‐hexylthiophene) (P3HT):poly(9,9‐dioctylfluorene‐co‐benzothiadiazole) (F8BT) active blends. The morphology and the local active polymer mixing are changed by depositing the active layer from four different solvents and by thermal annealing. The simultaneous PL and EQE mapping allowed us to inspect the effects of local irregularities of active layer thickness, polymer mixing, polymer aggregation on the charge generation and collection efficiencies. In particular, we show that the increase of the solvent boiling point affects the EQE non‐uniformity due to thickness fluctuations, the density non‐uniformity of rrP3HT aggregate phase, and the blend components clustering. The thermal annealing leads to a general improvement of EQE and to an F8BT clustering in all the samples with locally decrease of the EQE. We estimate that the film uniformity optimization can lead to a total EQE improvement between 2.7 and 6.3 times. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 804–813 相似文献
994.
Chen Dan Dan He Zhi Qiang Wang Min Wu Di Chen Xiang Ying Zhang Zhong Jie 《Journal of Solid State Electrochemistry》2020,24(3):641-654
Journal of Solid State Electrochemistry - In the present work, we demonstrate a strategy of combining boron doping and porosity engineering for a highly modulated carbon component and pore... 相似文献
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Di Turo Francesca Parra Rafael Piquero-Cilla Joan Favero Gabriele Doménech-Carbó Antonio 《Journal of Solid State Electrochemistry》2019,23(3):771-781
Journal of Solid State Electrochemistry - Electrochemical impedance spectroscopy (EIS) and voltammetry of immobilized particles (VIMP) measurements using air-saturated mineral water and... 相似文献
996.
Maria Ciaccia Irene Tosi Laura Baldini Roberta Cacciapaglia Luigi Mandolini Stefano Di Stefano Christopher A. Hunter 《Chemical science》2015,6(1):144-151
A new strategy for determining thermodynamic effective molarities (EM) for macrocylisation reactions using dynamic combinatorial chemistry under dilute conditions is presented. At low concentrations, below the critical value, Dynamic Libraries (DLs) of bifunctional building blocks contain only cyclic species, so it is not possible to quantify the equilibria between linear and cyclic species. However, addition of a monofunctional chain stopper can be used to promote the formation of linear oligomers allowing measurement of EM for all cyclic species present in the DL. The effectiveness of this approach was demonstrated for DLs generated from mixtures of 1,3-diimine calix[4]arenes, linear diaminoalkanes and monoaminoalkanes. For macrocycles deriving from one bifunctional calixarene and one diamine, there is an alternating pattern of EM values with the number of methylene units in the diamine: odd numbers give significantly higher EMs than even numbers. For odd numbers of methylene units, the alkyl chain can adopt an extended all anti conformation, whereas for even numbers of methylene units, gauche conformations are required for cyclisation, and the associated strain reduces EM. The value of EM for the five-carbon linker indicates that this macrocycle is a strainless ring. 相似文献
997.
利用非径向-SBM和CCR模型测算了我国30个省市(暂不包括西藏和港澳台地区)2007-2016年间的环境规制强度以及能源效率,构建面板平滑转移回归模型(PSTR),分析了环境规制强度对我国能源效率的连续非线性变化的影响.研究结果显示,全国环境规制强度对我国能源效率存在非线性效应,二者之间呈倒“U”型关系.环境规制强度小于门槛值0.6376时,环境规制对能源效率产生创新补偿效应,当环境规制强度高于门槛值0.6376时,环境规制对能源效率产生遵循成本效应.而我国东西部地区的环境规制强度与地区能源效率间却存在着与之相反的“U”型效应. 相似文献
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1000.
Development and validation of an LC‐MS/MS method for the determination of mesalazine in beagle dog plasma and its application to a pharmacokinetic study
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A simple, specific and sensitive LC‐MS/MS method was developed and validated for the determination of mesalazine in beagle dog plasma. The plasma samples were prepared by protein precipitation, then the separation of the analyte was achieved on a Waters Spherisorb C6 column (150 × 4.6 mm, 5 µm) with a mobile phase consisting of 0.2% formic acid in water–methanol (20:80, v/v). The flow rate was set at 1.0 mL/min with a split ratio of 3:2. Mass spectrometric detection was achieved by a triple‐quadrupole mass spectrometer equipped with an electrospray source interface in positive ionization mode. Quantitation was performed using selected reaction monitoring of precursor–product ion transitions at m/z 154 → m/z 108 for mesalazine and m/z 285 → m/z 193 for diazepam (internal standard). The linear calibration curve of mesalazine was obtained over the concentration range 50–30,000 ng/mL. The matrix effect of mesalazine was within ±9.8%. The intra‐ and inter‐day precisions were <7.9% and the accuracy (relative error) was within ±3.5%. The validated method was successfully applied to investigate the pharmacokinetics of mesalazine in healthy beagle dogs after rectal administration of mesalazine suppository. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献