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排序方式: 共有173条查询结果,搜索用时 15 毫秒
141.
Thibaut Forestier Dr. Abdellah Kaiba Dr. Stanislav Pechev Dr. Dominique Denux Philippe Guionneau Dr. Céline Etrillard Nathalie Daro Eric Freysz Jean‐François Létard Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6122-6130
By changing the surfactant/water ratio , nanoparticles of the iron(II) spin crossover material, [Fe(NH2‐trz)3]Br2 ? 3 H2O (with NH2‐trz=4‐amino‐1,2,4‐triazole), have been synthesised from 1 μm down to 30 nm (see figure). Magnetic and reflectivity experiments indicate that the critical size for observing a thermal hysteresis in this 1D polymer family is around 50 nm, and powder X‐ray diffraction shows that particles of about 30 nm are constituted by about one coherent domain.
142.
143.
In this study, a solvothermal method was used to synthesize anatase titanium dioxide (TiO2) nanoparticles in the presence of oleic acid (OA) and oleylamine (OM) as morphology‐directing agents. Functional nanocomposite fibers of poly(ethylene terephtalate) (PET) containing surfactants‐capped TiO2 nanoparticles were developed by electrospinning technique. The morphology, thermal stability and mechanical properties of PET/TiO2 nanocomposite mats were investigated as a function of TiO2 concentration. Morphology investigation showed interesting results in terms of the level of TiO2 dispersion inside the fibers and the improvement of the quality (smoothness) of the fibers' surface when the synthesized nanorhombic TiO2 nanoparticles were used compared to a commercial P25 TiO2 (AEROXIDE P25). The presence of OA and OM on the surface of the nanorhombic synthesized TiO2 led to a significant improvement of TiO2 dispersion inside the PET matrix. Furthermore, the physical interaction between the PET matrix and TiO2 nanoparticles resulted in an enhanced thermal stability, and an increase of the Young's modulus and tensile strength for TiO2 concentration up to 10 wt%. 相似文献
144.
Adnane Aouidate Adib Ghaleb Mounir Ghamali Samir Chtita Abdellah Ousaa M’barek Choukrad Abdelouahid Sbai Mohammed Bouachrine Tahar Lakhlifi 《Structural chemistry》2018,29(4):1031-1043
Cell division cycle 7 (CDC7) is a serine/threonine kinase, which plays a vital role in the replication initiation of DNA synthesis. Overexpression of the CDC7 in various tumor growths and in cell proliferation makes it a promising target for treatment of cancers. To investigate the binding between the CDC7 and furanone inhibitors, and in order to design highly potent inhibitors, a three-dimensional quantitative structure activity relationship (3D-QSAR) with molecular docking was performed. The optimum CoMSIA model showed significant statistical quality on all validation methods with a determination coefficient (R2?=?0.945), bootstrapping R2 mean (BS-R2?=?0.960), and leave-one-out cross-validation (Q2) coefficient of 0.545. The predictability of this model was evaluated by external validation using a test set of nine compounds with a predicted determination coefficient R2test of 0.96, besides the mean absolute error (MAE) of the test set was 0.258 log units. The extracted contour maps were used to identify the important regions, where the modification was necessary to design a new molecule with improved activity. Furthermore, a good consistency between the molecular docking and contour maps strongly demonstrates that the molecular modeling is reliable. Based on those obtained results, we designed several new potent CDC7 inhibitors, and their inhibitory activities were validated by the molecular models. Additionally, those newly designed inhibitors showed promising results in the preliminary in silico ADMET evaluations. 相似文献
145.
Adnane Aouidate Adib Ghaleb Mounir Ghamali Samir Chtita Abdellah Ousaa M’barek Choukrad Abdelouahid Sbai Mohammed Bouachrine Tahar Lakhlifi 《Structural chemistry》2018,29(6):1609-1622
Kinase-related apoptosis-inducing kinase 2 (DRAK2) is a serine/threonine kinase and belongs to the death-associated protein kinase DPAK family, which is responsible for induction of apoptosis in many cell types. Thus, DRAK2 is regarded as a promising target for treatment of autoimmune diseases. To investigate the binding between DRAK2 and indirubin inhibitors and design potent inhibitors, a three-dimensional quantitative structure-activity relationship (3D-QSAR) and molecular docking were performed. Comparative Molecular Similarity Indices Analysis (CoMSIA) was developed using 33 molecules having pIC50 ranging from 8.523 to 5.000 (IC50 in nM). The best CoMSIA model gave a significant coefficient of determination (R2?=?0.93), as well as a (leave-one-out cross-validation coefficient Q2 of 0.81. The predictive ability of this model was evaluated by external validation using a test set of eight compounds and yielded a predicted coefficient of determination R2test of 0.94. The contour maps could provide structural features to improve inhibitory activity. Good consistency between contour maps and molecular docking strongly suggests that the molecular modeling is reliable. Based on these satisfactory results, we designed several new DRAK2 inhibitors and their inhibitory activities were predicted using different models, which are developed on different training and test sets. Additionally, these newly designed inhibitors showed promising results in the preliminary in silico ADMET evaluations compared to the best inhibitor from the studied dataset. This study could be useful in lead identification and optimization for early drug discovery of DRAK2 inhibitors. 相似文献
146.
The electrical resistivity of liquid alkali metals was calculated using the extended Ziman formula. The possible role of Fermi surface (FS) inflation–deflation (ID) was examined. The calculations reveal that replacing the sharp free electron FS by the expanded (respectively, contracted) one substantially improves the results. This was achieved directly by considering a FS correction factor of the Fermi radius and indirectly by a shift in the muffin-tin zero (MTZ) of the potential from its initial values. Consequently, a correlation between the shift of the MTZ of the potential and the FS factor parameter is revealed. The role of this correlation might contribute to a better understanding of the electron transport properties of other liquid metals and their alloys. 相似文献
147.
In this paper, a close connection is established between the geometry of certain genus zero Fuchsian groups and the analytic
properties of the automorphic forms obtained by applying a certain differential operator to the Hauptmoduls of the groups.
Received April 8, 1999 / Revised January 10, 2000 / Published online July 20, 2000 相似文献
148.
Abdellah Henni Abdallah Merrouche Laid Telli Amina Karar Fabian I. Ezema Hichem Haffar 《Journal of Solid State Electrochemistry》2016,20(8):2135-2142
Indium-doped zinc oxide nanorods were electrochemically deposited at low temperature on ITO substrates. The synthesized ZnO-arrayed layers were investigated by using X-ray diffraction, scanning electron microscopy, UV–vis transmittance, electrochemical impedance spectroscopy, and photocurrent spectroscopy. X-ray diffraction analysis demonstrates that the electrodeposited films are crystalline and present the hexagonal Würtzite ZnO phase with preferential (002) orientation. The ZnO films obtained forms aligned hexagonal nanorods, and depending on the increasing In concentration, the surface morphologies of the films are changed. The ln-doped ZnO nanorods (NRs) are well-aligned with the c-axis being perpendicular to the substrates when the ln concentration was between 0 and 2 at.%. of In, the grown films with In contents up to 4 at.%, changes in the optical band gap from 3.31 to 3.39 eV, and the blue shift in the band gap energy was attributed to the Burstein–Moss effect. The effect of In concentration on the photocurrent generated by films shows that the obtained thin films can be used as a photovoltaic material. Changes in the photocurrent response and the electronic disorder were also discussed in the light of In doping. It was found that the carrier density of IZO thin films varied between 1.06?×?1018 and 1.88?×?1018 cm?3 when the In concentration was between 0 and 4 at.%. 相似文献
149.
Thermal spray coatings are affected by various parameters. In this study, the finite element method with volume of fluid (VOF) procedure is used to investigate the deposition process which is very important for the quality of sprayed coatings. The specific heat method (SHM) is used for the solidification phenomenon. A comparison of the present model with experimental and numerical model available in the literature is done. A series of numerical calculations is carried out to investigate the effect of the surrounding gas temperature on the splat formation. The variation of the surrounding gas temperature has a significant effect on splat morphology and can affect the adhesion of the splat on the substrate. 相似文献
150.
Abdellah Bnouhachem Muhammad Aslam Noor Mohamed Khalfaoui 《Applied mathematics and computation》2007,190(2):1691-1700
In this paper, we propose a modified descent-projection method for solving variational inequalities. The method makes use of a descent direction to produce the new iterate and can be viewed as an improvement of the descent-projection method by using a new step size. Under certain conditions, the global convergence of the proposed method is proved. In order to demonstrate the efficiency of the proposed method, we provide numerical results for a traffic equilibrium problems. 相似文献