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排序方式: 共有1103条查询结果,搜索用时 31 毫秒
141.
Dr. Esteban G. Vega Hissi Antonella B. De Costa Guardamagna Dr. Adriana D. Garro Dr. Cristian R. Falcon Dr. Marko Anderluh Dr. Tihomir Tomašič Dr. Danijel Kikelj Dr. Agustín Yaneff Dr. Carlos A. Davio Dr. Ricardo D. Enriz Dr. Adolfo R. Zurita. 《ChemMedChem》2021,16(13):2094-2105
In this work, we report a derivative of N-(piperidin-4-yl)-1H-pyrrole-2-carboxamide as a new inhibitor for adenylyl cyclase of Giardia lamblia which was obtained from a study using structural data of the nucleotidyl cyclase 1 (gNC1) of this parasite. For such a study, we developed a model for this specific enzyme by using homology techniques, which is the first model reported for gNC1 of G. lamblia. Our studies show that the new inhibitor has a competitive mechanism of action against this enzyme. 2-Hydroxyestradiol was used as the reference compound for comparative studies. Results in this work are important from two points of view. on the one hand, an experimentally corroborated model for gNC1 of G. lamblia obtained by molecular modelling is presented; on the other hand, the new inhibitor obtained is an undoubtedly excellent starting structure for the development of new metabolic inhibitors for G. lamblia. 相似文献
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Adriana Marinoiu Elena Carcadea Ada Sacca Alessandra Carbone Claudia Sisu Andreea Dogaru Mircea Raceanu Mihai Varlam 《International Journal of Hydrogen Energy》2021,46(22):12242-12253
Here in, we describe an ultrafast, single-step microwave irradiation route (MW) to prepare graphene supported Pt nanoparticles, during which the small Pt nanoparticles are distributed uniformly on a reduced graphene oxide surface. This route provides evident advantages namely low cost, easiness, low time consuming and high yield in comparison to actual chemical methods to develop efficient Pt/rGO catalyst with Pt content close to state-of-the-art commercial composition. The structure and composition of prepared samples have been studied by specific techniques, while the electrocatalytic stability has been studied using ex-situ and in-situ measurements. High performance and electrochemically stable catalyst for PEM fuel cells was developed using the sample with highest loading and good dispersion. The fabricated Pt-rGO-based MEA was investigated for durability under fuel starvation in comparison with commercial Pt/C-based MEA. The electrocatalytic activity was investigated and the electrochemical response revealed the higher stability during accelerated degradation test under fuel starvation in comparison with commercial Pt/C. This study promotes the applicability of described preparation method to noble or transition metal nanoparticles embedded on graphene-based materials. 相似文献
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Hua Lv Alessandra da Silva Adriana I. Figueroa Charles Guillemard Iván Fernández Aguirre Lorenzo Camosi Lucia Aballe Manuel Valvidares Sergio O. Valenzuela Jürgen Schubert Martin Schmidbauer Jens Herfort Michael Hanke Achim Trampert Roman Engel-Herbert Manfred Ramsteiner Joao Marcelo J. Lopes 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(39):2302387
Van der Waals (vdW) heterostructures combining layered ferromagnets and other 2D crystals are promising building blocks for the realization of ultracompact devices with integrated magnetic, electronic, and optical functionalities. Their implementation in various technologies depends strongly on the development of a bottom-up scalable synthesis approach allowing for realizing highly uniform heterostructures with well-defined interfaces between different 2D-layered materials. It is also required that each material component of the heterostructure remains functional, which ideally includes ferromagnetic order above room temperature for 2D ferromagnets. Here, it is demonstrated that the large-area growth of Fe5−xGeTe2/graphene heterostructures is achieved by vdW epitaxy of Fe5−xGeTe2 on epitaxial graphene. Structural characterization confirms the realization of a continuous vdW heterostructure film with a sharp interface between Fe5−xGeTe2 and graphene. Magnetic and transport studies reveal that the ferromagnetic order persists well above 300 K with a perpendicular magnetic anisotropy. In addition, epitaxial graphene on SiC(0001) continues to exhibit a high electronic quality. These results represent an important advance beyond nonscalable flake exfoliation and stacking methods, thus marking a crucial step toward the implementation of ferromagnetic 2D materials in practical applications. 相似文献
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Cytotoxic Activity and Structure–Activity Relationship of Triazole‐Containing Bis(Aryl Ether) Macrocycles
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Dr. Eduardo Hernández‐Vázquez Dr. Alejandra Chávez‐Riveros Dr. Adriana Romo‐Pérez María Teresa Ramírez‐Apán Dr. Alma D. Chávez‐Blanco Dr. Rocío Morales‐Bárcenas Dr. Alfonso Dueñas‐González Dr. Luis D. Miranda 《ChemMedChem》2018,13(12):1193-1209
Cancer continues to be a worldwide health problem. Certain macrocyclic molecules have become attractive therapeutic alternatives for this disease because of their efficacy and, frequently, their novel mechanisms of action. Herein, we report the synthesis of a series of 20‐, 21‐, and 22‐membered macrocycles containing triazole and bis(aryl ether) moieties. The compounds were prepared by a multicomponent approach from readily available commercial substrates. Notably, some of the compounds displayed interesting cytotoxicity against cancer (PC‐3) and breast (MCF‐7) cell lines, especially those bearing an aliphatic or a trifluoromethyl substituent on the N‐phenyl moiety (IC50<13 μm ). Additionally, some of the compounds were able to induce apoptosis relative to the solvent control; in particular, (Z)‐N‐cyclohexyl‐7‐oxo‐6‐[4‐(trifluoromethyl)phenyl]‐11H‐3,10‐dioxa‐6‐aza‐1(4,1)‐triazola‐4(1,3),9(1,4)‐dibenzenacyclotridecaphane‐5‐carboxamide ( 12 f ) was the most potent in this regard (22.7 % of apoptosis). 相似文献
150.
Baake O Seidl T Hossain UH Delgado AO Bender M Severin D Ensinger W 《The Review of scientific instruments》2011,82(4):045103
A new target station providing Fourier transform infrared (FT-IR) spectroscopy and residual gas analysis (RGA) for in situ observation of ion-induced changes in polymers has been installed at the GSI Helmholtz Centre for Heavy Ion Research. The installations as well as first in situ measurements at room temperature are presented here. A foil of polyimide Kapton HN(?) was irradiated with 1.1 GeV Au ions. During irradiation several in situ FT-IR spectra were recorded. Simultaneously outgassing degradation products were detected with the RGA. In the IR spectra nearly all bands decrease due to the degradation of the molecular structure. In the region from 3000 to 2700 cm(-1) vibration bands of saturated hydrocarbons not reported in literature so far became visible. The outgassing experiments show a mixture of C(2)H(4), CO, and N(2) as the main outgassing components of polyimide. The ability to combine both analytical methods and the opportunity to measure a whole fluence series within a single experiment show the efficiency of the new setup. 相似文献