排序方式: 共有68条查询结果,搜索用时 15 毫秒
51.
Youghourta Belhocine Seyfeddine Rahali Hamza Allal Ibtissem Meriem Assaba Monira Galal Ghoniem Fatima Adam Mohamed Ali 《Molecules (Basel, Switzerland)》2021,26(24)
The encapsulation mode of dexamethasone (Dex) into the cavity of β-cyclodextrin (β-CD), as well as its potential as an inhibitor of the COVID-19 main protease, were investigated using density functional theory with the recent dispersion corrections D4 and molecular docking calculations. Independent gradient model and natural bond orbital approaches allowed for the characterization of the host–guest interactions in the studied systems. Structural and energetic computation results revealed that hydrogen bonds and van der Waals interactions played significant roles in the stabilization of the formed Dex@β-CD complex. The complexation energy significantly decreased from −179.50 kJ/mol in the gas phase to −74.14 kJ/mol in the aqueous phase. A molecular docking study was performed to investigate the inhibitory activity of dexamethasone against the COVID-19 target protein (PDB ID: 6LU7). The dexamethasone showed potential therapeutic activity as a SARS CoV-2 main protease inhibitor due to its strong binding to the active sites of the protein target, with predicted free energy of binding values of −29.97 and −32.19 kJ/mol as calculated from AutoDock4 and AutoDock Vina, respectively. This study was intended to explore the potential use of the Dex@β-CD complex in drug delivery to enhance dexamethasone dissolution, thus improving its bioavailability and reducing its side effects. 相似文献
52.
Nikolay Gerasimchuk Lauri Kivijarvi Bruce Noll Meriem Goudjil Soma Khanra Yu Ping Miles Pearson Frank Rminger 《Molecules (Basel, Switzerland)》2021,26(5)
Interactions between well-mixed fine powders of As2O3, P2O5, MoO3, WO3 and Nb2O5 at different stoichiometry in quartz ampoules under vacuum at ~1000 °C in the presence of metallic molybdenum (or niobium), over several weeks, led to shiny dichroic crystalline materials being formed in cooler parts of the reaction vessel. An addition of small quantities of metals-Mo or Nb-was made with the aim of partially reducing their highly oxidized Mo(VI), W(VI) or Nb(V) species to corresponding Mo(V), W(V) and Nb(IV) centers, in order to form mixed valence solids. Sublimed crystals of four new compounds were investigated using a variety of techniques, with prime emphasis on the X-ray analysis, followed by spectroscopy (diffusion reflectance, IR, Raman and EPR), second harmonic generation (SHG), thermal analysis under N2 and air atmosphere, and single crystals electrical conductivity studies. The results evidenced the formation of new complex solids of previously unknown compositions and structures. Three out of four compounds crystallized in non-centrosymmetric space groups and represent layered 2D polymeric puckered structures that being stacked on each other form 3D lattices. All new solids exhibit strong second-harmonic-generation (SHG effect; based on YAG 1064 nm tests with detection of 532 nm photons), and a rare photosalient effect when crystals physically move in the laser beam. Single crystals’ electrical conductivity of the four new synthesized compounds was measured, and the results showed their semiconductor behavior. Values of band gaps of these new solids were determined using diffusion reflectance spectroscopy in the visible region. Aspects of new solids’ practical usefulness are discussed. 相似文献
53.
Outaki Meriem Gmouh Said Bazi Fathallaah Kerak Ebrahim 《Accreditation and quality assurance》2019,24(5):395-404
Accreditation and Quality Assurance - The implementation of a quality management system including management tools in the industrial sector has several advantages. In this perspective, can we use... 相似文献
54.
Liu Wei Wang Ruya Hu Fan Wu Pinping Huang Tao Fizir Meriem He Hua 《Analytical and bioanalytical chemistry》2018,410(28):7357-7371
Analytical and Bioanalytical Chemistry - The co-adsorption of mixed nonionic surfactant and imidazolium-based ionic liquid, Triton X100 (TX100), with 1-cetyl-3-methylimidazolium bromide (C16mimBr)... 相似文献
55.
Amin Boumenir Mohamed Ghattassi Taous Meriem Laleg-Kirati 《Mathematical Methods in the Applied Sciences》2020,43(3):1399-1408
This paper deals with the heat transfer monitoring occurring within an inaccessible membrane distillation system. The membrane separates heated sea water and filtered cooled drinkable water. By adjusting the temperature of the incoming heated sea water and knowing its temperature distribution, engineers can keep its temperature within its best operating parameters and avoid hot spots to form. This would help prolong its life cycle and minimize the cost of the distillation process. In particular, we show that an external observation is enough to reconstruct the temperature of the membrane, which is considered as an unknown source term in a parabolic system. 相似文献
56.
Using the Monte Carlo N-Particle code (MCNP-6), to analyze the thermal, epithermal and fast neutron fluxes, of 3 millicuries of radium–beryllium, for determine the qualitative and quantitative of many materials, using method of neutron activation analysis. Radium–beryllium source of neutron is established to practical work and research in nuclear field. The main objective of this work was to enable us harness the profile flux of radium–beryllium irradiation, this theoretical study permits to discuss the design of the optimal irradiation and performance for increased the facility research and education of nuclear physics. 相似文献
57.
Benmelouka M Borel A Moriggi L Helm L Merbach AE 《The journal of physical chemistry. B》2007,111(4):832-840
A multiple-frequency (9.4-325 GHz) and variable-temperature (276-320 K) electron paramagnetic resonance (EPR) study on low molecular weight gadolinium(III) complexes for potential use as magnetic resonance imaging (MRI) contrast agents has been performed. Peak-to-peak linewidths Delta Hpp and central magnetic fields have been analyzed within the Redfield approximation taking into account the static zero-field splitting (ZFS) up to the sixth order and the transient ZFS up to the second order. Longitudinal electronic relaxation is dominated by the static ZFS contribution at low magnetic fields (B < 0.3 T) and by the transient ZFS at high magnetic fields (B > 1.5 T). Whereas the static ZFS clearly depends on the nature of the chelating ligand, the transient ZFS does not. For the relatively fast rotating molecules studied water proton relaxivity is mainly limited by the fast rotation and electronic relaxation has only a marked influence at frequencies below 30 MHz. From our EPR results we can conclude that electronic relaxation will have no influence on the efficiency of Gd(III)-based MRI contrast agents designed for studies at very high magnetic fields (B > 3T). 相似文献
58.
El Marsi Meriem Elmaddahi Zakaria Fechtal Imad Dezairi Aouatif 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3795-3806
Journal of Radioanalytical and Nuclear Chemistry - Tungsten (W) plays a crucial role in the lifetime of the plasma-facing components of DEMO. In order to avoid oxidation, W-based alloys have been... 相似文献
59.
Meriem Lamouchi Erwann Jeanneau Rodica Chiriac Didier Ceroni Faouzi Meganem Arnaud Brioude Anthony W. Coleman Cédric Desroches 《Tetrahedron letters》2012,53(16):2088-2090
A clean and partially green route to monoalkyled thiacalix[4]arenes has been demonstrated. We have discovered that tetraalkylammonium halide can cleave selectively one of the two aryl alkyl ethers of dialkylated para-tert-butylthiacalix[4]arenes. Thus, p-tert-butyl thiacalix[4]arenes differently monoalkyled at the lower rim with acetyl, propyl, and benzyl group were synthesized in good yield. 相似文献
60.
The b-chromatic number of a graph G is the largest integer k such that G has a coloring of the vertices in k color classes such that every color class contains a vertex that has a neighbour in all other color classes. We characterize
the class of chordal graphs for which the b-chromatic number is equal to the chromatic number for every induced subgraph.
This research was supported by Algerian-French program CMEP/Tassili 05 MDU 639. 相似文献