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排序方式: 共有691条查询结果,搜索用时 15 毫秒
681.
Dr. Mathew Sutherland Alice Li Anissa Kaghad Dimitrios Panagopoulos Dr. Fengling Li Dr. Magdalena Szewczyk Dr. David Smil Dr. Cora Scholten Dr. Léa Bouché Dr. Timo Stellfeld Dr. Cheryl H. Arrowsmith Dr. Dalia Barsyte Dr. Masoud Vedadi Dr. Ingo V. Hartung Dr. Holger Steuber Dr. Robert Britton Dr. Vijayaratnam Santhakumar 《ChemMedChem》2021,16(7):1116-1125
Protein arginine N-methyl transferase 4 (PRMT4) asymmetrically dimethylates the arginine residues of histone H3 and nonhistone proteins. The overexpression of PRMT4 in several cancers has stimulated interest in the discovery of inhibitors as biological tools and, potentially, therapeutics. Although several PRMT4 inhibitors have been reported, most display poor selectivity against other members of the PRMT family of methyl transferases. Herein, we report the structure-based design of a new class of alanine-containing 3-arylindoles as potent and selective PRMT4 inhibitors, and describe key structure–activity relationships for this class of compounds. 相似文献
682.
Theodoros K. Katranas Konstantinos S. Triantafyllidis Athanasios G. Vlessidis Nicholaos P. Evmiridis 《Catalysis Letters》2007,118(1-2):79-85
In this work we prepared various zeolite-X and USY samples partially exchanged with copper, iron and platinum. These samples
were characterized by XRD, Chemical Analysis, SEM-EDS, N2-adsorption–desorption, ammonia-TPD, and tested as catalysts in high temperature (400 and 550 °C) propane transformation.
The obtained results revealed the strong effect of Si/Al ratio in faujasite zeolite structure, the number and strength of
acid sites and of the presence of different metal ions in countered ion sites, on the catalytic activity and selectivity of
zeolite-X and USY. The highest propane dehydrogenation activity was achieved with the platinum-exchanged X zeolite (∼11.2%
propylene yield, ∼31% selectivity). On the contrary USY zeolites showed high cracking capability and relatively low dehydrogenation
activity excepting the platinum-exchanged sample which yielded notably high aromatization products. 相似文献
683.
Ignatios Fotiou Athanasios Baltopoulos Antonios Vavouliotis Vassilis Kostopoulos 《应用聚合物科学杂志》2013,129(5):2754-2764
The driver for this study is the observation that heating of carbon nanotubes (CNTs) with electromagnetic field can offer a more efficient and cost‐effective alternative in heat transfer for the production of composites. The idea of this study is twofold; CNT can work as microwave (MW) radiation susceptors and they can act as nanoreinforcements in the final system. To test these assumptions, a household oven was modified to control the curing schedule. Polymers with different CNT concentrations were prepared (0.5 and 1.0 wt %). The dispersion of the CNTs in the epoxy was achieved using shear‐mixing dissolver technique. MW and conventionally cured specimens were also produced in a convection oven for reference. Thermal and mechanical tests were used as control point. A curing schedule investigation was further performed to quantify the energy and time‐saving capabilities using CNT and MWs. The presence of CNTs into epoxy matrix has been proven beneficial for the shortening of the curing time. MW‐cured composites showed the same degree of polymerization with the conventionally cured composites in a shorter time period and this time was reduced as the CNT concentration was increased. A good distribution of the CNT is required to avoid hot spot effects and local degradation. Mechanical performance was, in some cases, favored by the use of CNT. The benefit from the use of MWs and CNT could reach at least 40% in terms of energy needed and time without sacrificing mechanical performance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
684.
The effect of various heat treatments on the corrosion behaviour of 319 T1 cast aluminium alloy was investigated. From this alloy, specimens were heat treated in T5, T6 and two steps solution heat treatment T6 conditions and afterwards were subjected to electrochemical corrosion in a 0.1 M NaCl solution (pH = 12). From the above treatments, T5 heat treatment did not improve the corrosion resistance of the as‐received alloy in contrast to T6 heat treatment which improved the corrosion resistance of the same alloy. However, two steps solutionizing T6 treatment showed the best corrosion resistance of the aluminium alloy. 相似文献
685.
Panagiotis Dallas Athanasios B. Bourlinos Philomela Komninou Michael Karakassides Dimitrios Niarchos 《Nanoscale research letters》2009,4(11):1358-1364
Spherically shaped silver nanoparticles embedded in a carbon matrix were synthesized by thermal decomposition of a Ag(I)/acetylenedicarboxylic acid salt. The silver nanoparticles, which are formed either by pyrolysis at 300 °C in an autoclave or thermolysis in xylene suspension at reflux temperature, are acting catalytically for the formation of graphite layers. Both reactions proceed through in situ reduction of the silver cations and polymerization of the central acetylene triple bonds and the exact temperature of the reaction can be monitored through DTA analysis. Interestingly, the thermal decomposition of this silver salt in xylene partly leads to a minor fraction of quasicrystalline silver, as established by HR-TEM analysis. The graphitic layers covering the silver nanoparticles are clearly seen in HR-TEM images and, furthermore, established by the presence of sp2 carbon at the Raman spectrum of both samples. 相似文献
686.
Complexity of power plant evaluation is steadily rising, as more criteria are involved in the overall assessment while evaluation data change rapidly. Apart from evaluating several aspects of power plants separately, a multicriteria analysis based on hierarchically structured criteria is necessary, so as to address the overall assessment of power plants according to the technological, economic and sustainability aspects. For this reason, in this paper, ten types of power plant are evaluated using nine end node criteria properly structured under the Analytical Hierarchy Process. Moreover, pairwise comparisons allow for accurate subjective criteria weighting. 相似文献
687.
688.
689.
Athanasios V. Vasilakos Liu Wei Tran Cong Thien Qui Clara Boj Adrian David Cheok 《Information Sciences》2008,178(3):679-693
Our system of Mixed Reality and 3D Live with Ambient Intelligence (AmI) is indented to bring performance art to the people while offering to the performance artists a creative tool to extend the grammar of the traditional theatre. Actors and dancers at different places are captured by multiple cameras and their images are rendered in 3D form in such a way that they can play and dance together on the same place in real-time. Our Quanticum Man is an allegory of the time of the General Relativity and the matter of the Quantum Mechanics. The new type of interactive theatre enables social networking by supporting simultaneous participants in human-to-human social manner. 相似文献
690.
Athanasios K. Tsadiras 《Information Sciences》2008,178(20):3880-3894
In this paper, we compare the inference capabilities of three different types of fuzzy cognitive maps (FCMs). A fuzzy cognitive map is a recurrent artificial neural network that creates models as collections of concepts/neurons and the various causal relations that exist between these concepts/neurons. In the paper, a variety of industry/engineering FCM applications is presented. The three different types of FCMs that we study and compare are the binary, the trivalent and the sigmoid FCM, each of them using the corresponding transfer function for their neurons/concepts. Predictions are made by viewing dynamically the consequences of the various imposed scenarios. The prediction making capabilities are examined and presented. Conclusions are drawn concerning the use of the three types of FCMs for making predictions. Guidance is given, in order FCM users to choose the most suitable type of FCM, according to (a) the nature of the problem, (b) the required representation capabilities of the problem and (c) the level of inference required by the case. 相似文献