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排序方式: 共有547条查询结果,搜索用时 15 毫秒
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Silvia Gentiluomo Dr. Sanjay B. Thorat Dr. Antonio Esau Del Río Castillo Dr. Peter S. Toth Dr. Jaya Kumar Panda Dr. Vittorio Pellegrini Dr. Francesco Bonaccorso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6715-6725
One of the applications of graphene in which its scalable production is of utmost importance is the development of polymer composites. Among the techniques used to produce graphene flakes, the liquid-phase exfoliation (LPE) of graphite stands out due to its versatility and scalability. However, solvents suitable for the LPE process are generally toxic and have a high boiling point, making the processing challenging. The use of low boiling point solvents could be convenient for the processing, due to the easiness of their removal. In this study, the use of poly(methyl methacrylate) (PMMA) as a stabilizing agent is proposed for the production of graphene flakes in a low boiling point solvent, that is, acetone. The graphene dispersions produced in the mixture acetone-PMMA have higher concentration, +175 %, and contain a higher percentage of few-layer graphene flakes (<5 layers), that is, +60 %, compared to the dispersions prepared in acetone. The as-produced graphene dispersions are used to develop graphene/acrylonitrile-butadiene-styrene composites. The mechanical properties of the pristine polymer are improved, that is, +22 % in the Young's modulus, by adding 0.01 wt. % of graphene flakes. Moreover, a decrease of ≈20 % in the oxygen permeability is obtained by using 0.1 wt. % of graphene flakes filler, compared to the unloaded matrix. 相似文献
104.
Pier Vittorio Ceccherini 《Results in Mathematics》1997,32(3-4):221-233
105.
Jochen Bartels Vittorio Del Duca Mark Wüsthoff 《Zeitschrift fur Physik C Particles and Fields》1997,76(1):75-79
As a signal for the BFKL Pomeron in small-x deep inelastic ep scattering, we calculate the azimuthal dependence of the inclusive cross section of forward jets relative to the outgoing electron. For not very large differences in rapidity between the current jet and the forward jet the cross section peaks at π/2. For increasing rapidity BFKL dynamics predicts a decorrelation in the azimuthal dependence between the electron and the forward jet. 相似文献
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107.
Exploiting Synergistic Effects in Organozinc Chemistry for Direct Stereoselective C‐Glycosylation Reactions at Room Temperature
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Dr. Alberto Hernán‐Gómez Dr. Samantha A. Orr Dr. Marina Uzelac Dr. Alan R. Kennedy Dr. Santiago Barroso Dr. Xavier Jusseau Dr. Sébastien Lemaire Dr. Vittorio Farina Prof. Eva Hevia 《Angewandte Chemie (International ed. in English)》2018,57(33):10630-10634
Pairing a range of bis(aryl) zinc reagents ZnAr2 with the stronger Lewis acidic [(ZnArF2)] (ArF=C6F5), enables highly stereoselective cross‐coupling between glycosyl bromides and ZnAr2 without the use of a transition metal. Reactions occur at room temperature with excellent levels of stereoselectivity, where ZnArF2 acts as a non‐coupling partner although its presence is crucial for the execution of the C(sp2)–C(sp3) bond formation process. Mechanistic studies have uncovered a unique synergistic partnership between the two zinc reagents, which circumvents the need for transition‐metal catalysis or forcing reaction conditions. Key to the success of the coupling is the avoidance of solvents that act as Lewis bases versus diarylzinc compounds (e.g. THF). 相似文献
108.
Recently the low-energy effective string theory has been used by Gasperini and Veneziano to elaborate a very interesting scenario for the early history of the universe (birth of the universe as quantum scattering). Here we investigate the gauge fixing and the problem of the definition of a global time parameter for the quantum form of the model, and obtain the positive norm Hilbert space of states. 相似文献
109.
α-bromo Michael acceptors undergo ipso-substitution by phenol or benzenethiol in the K2CO3-acetone system, the reaction originating the (Z) isomers, via a stereospecific AdSNE process. 相似文献
110.
Affinity capillary electrophoresis is a powerful tool to identify transthyretin binding drugs for potential therapeutic use in amyloidosis 总被引:2,自引:0,他引:2
De Lorenzi E Galbusera C Bellotti V Mangione P Massolini G Tabolotti E Andreola A Caccialanza G 《Electrophoresis》2000,21(15):3280-3289
In this work we used affinity capillary electrophoresis (ACE) to investigate the extent of interaction between a pool of drugs and wild-type transthyretin. After qualitative preliminary screening, attention was focused on the most promising molecules, flufenamic acid and flurbiprofen, which underwent a further stage of investigation, the determination of the binding constants, and, when possible, the assessment of the number of binding sites by ACE, frontal analysis (FA) capillary electrophoresis (CE) and parallel ultrafiltration (UF) experiments. Furthermore, our data demonstrate that FA CE is a suitable technique for identifying fibril ligands. This represents a novel CE application of pharmaceutical interest. 相似文献