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51.
We argue that the statistical features of generalized coherent states for power-law potentials based on Heisenberg algebra, presented in a recent paper by Berrada et al. (2011) [1] are incorrect. 相似文献
52.
We study the resonant interaction of a beam of mono-velocity two-level atoms with a standing-wave light field in the Bragg
regime. The atomic beam consists of two different isotopes, and the density is sufficiently small so that at most one atom
is inside the cavity at a time. The momentum transfer between the atoms and photons in the process significantly effects the
center-of-mass motion of the atoms, thus separating the isotopes in different directions. 相似文献
53.
A recurrence tracking microscope works on quantum recurrence phenomena of the wave packet and probes nanostructures on a surface. The important advantage of condensed atoms over cold atoms is the very small distribution size due to the atom–atom interactions. We report a more precise measurement of the quantum revival time. For small nonlinear interatomic interactions, there is a small change in quantum revival times; however, as the interaction becomes stronger, we find visible changes in the revival time. The change in the initial height of the nanoparticles is due to the variation in the revival times at different positions of the cantilever. 相似文献
54.
The present study is carried out to see the thermal-diffusion (Dufour) and diffusion-thermo (Soret) effects on the mixed convection boundary layer flow of viscoelastic nanofluid flow over a vertical stretching surface in a porous medium. Optimal homotopy analysis method (OHAM) is best candidate to handle highly nonlinear system of differ-ential equations obtained from boundary layer partial differential equations via appropriate transformations. Graphical illustrations depicting different physical arising parameters against velocity, temperature and concentration distributions with required discussion have also been added. Numerically calculated values of skin friction coefficient, local Nusselt and Sherwood numbers are given in the form of table and well argued. It is found that nanofluid velocity increases with increase in mixed convective and viscoelastic parameters but it decreases with the increasing values of porosity parameter. Also, it is observed that Dufour number has opposite behavior on temperature and concentration profiles. 相似文献
55.
Ghazala Muteeb Abdulrahman Alsultan Mohd Farhan Mohammad Aatif 《Molecules (Basel, Switzerland)》2022,27(4)
Bacteria expressing New Delhi metallo-β-lactamase-1 (NDM-1) can hydrolyze β-lactam antibiotics (penicillins, cephalosporins, and carbapenems) and, thus, mediate multidrug resistance. The worldwide dissemination of NDM-1 poses a serious threat to public health, imposing a huge economic burden in the development of new antibiotics. Thus, there is an urgent need for the identification of novel NDM-1 inhibitors from a pool of already-known drug molecules. Here, we screened a library of FDA-approved drugs to identify novel non-β-lactam ring-containing inhibitors of NDM-1 by applying computational as well as in vitro experimental approaches. Different steps of high-throughput virtual screening, molecular docking, molecular dynamics simulation, and enzyme kinetics were performed to identify risedronate and methotrexate as the inhibitors with the most potential. The molecular mechanics/generalized Born surface area (MM/GBSA) and molecular dynamics (MD) simulations showed that both of the compounds (risedronate and methotrexate) formed a stable complex with NDM-1. Furthermore, analyses of the binding pose revealed that risedronate formed two hydrogen bonds and three electrostatic interactions with the catalytic residues of NDM-1. Similarly, methotrexate formed four hydrogen bonds and one electrostatic interaction with NDM-1’s active site residues. The docking scores of risedronate and methotrexate for NDM-1 were –10.543 kcal mol−1 and −10.189 kcal mol−1, respectively. Steady-state enzyme kinetics in the presence of risedronate and methotrexate showed a decreased catalytic efficiency (i.e., kcat/Km) of NDM-1 on various antibiotics, owing to poor catalytic proficiency and affinity. The results were further validated by determining the MICs of imipenem and meropenem in the presence of risedronate and methotrexate. The IC50 values of the identified inhibitors were in the micromolar range. The findings of this study should be helpful in further characterizing the potential of risedronate and methotrexate to treat bacterial infections. 相似文献
56.
Electrothermal atomic-absorption spectrometry is used for the determination of lead in tooth-pastes, by means of the graphite platform/matrix-modification technique. The method is easy to apply, has limited interferences and is more precise than conventional flame AAS. The working concentration range is up to 100 mug/1. The method is characterized by a detection limit of 0.08 mug/1. and a precision of +/-1.9 % for the sample solutions. For the tooth-pastes, the detection limit is between 1.1 and 5.4 ng/g and the precision in the range 1.8-10%. 相似文献
57.
Vahid Parvaneh Farhan Golkarmanesh Nawab Hussain Peyman Salimi 《Journal of Fixed Point Theory and Applications》2016,18(4):905-925
Recently, Jleli and Samet [J. Inequal. Appl. (2014), 2014:38] introduced and studied a new contraction to prove a generalization of the Banach contraction principle. In this paper, we introduce the concept of \({\alpha}\)-\({H\Theta}\)-contraction with respect to a general family of functions H and we establish Jleli–Samet-type fixed point results in metric and ordered metric spaces. As an application of our results we deduce Suzuki-type fixed point results for \({H\Theta}\)-contractions. We also derive certain fixed and periodic point results for orbitally continuous generalized \({\Theta}\)-contractions. Moreover, we present an illustrative example to highlight the obtained improvements. 相似文献
58.
Jad Rabah Anam Fatima Hélène Fensterbank Karen Wright Anne Vallée Maïssa Gueye Gotard Burdzinski Gilles Clavier Fabien Miomandre Julie Pham Michel Sliwa Rachel Méallet-Renault Karine Steenkeste Thomas Pino Minh-Huong Ha-Thi Emmanuel Allard 《Helvetica chimica acta》2023,106(6):e202300039
Ferrocene-BODIPY (Fc-BDP) conjugates in which one or two ferrocene entities are linked to the β-positions of the BODIPY core by an ethynyl bridge have been developed. These derivatives were easily and efficiently grafted onto a dual-clickable fullerene platform using CuAAC reactions, leading to a clickable Fc-BDP-C60 triad and a clickable [Fc]2-BDP-C60 tetrad which can be used for further derivatization with complex structures. Due to the extended π-conjugation and the presence of an intramolecular charge transfer band from Fc to BDP, all these conjugates display a broad absorption in the visible region, which is bathochromically shifted when two Fc are appended to the BDP core. Ultrafast multistep electron transfers leading to charge stabilization were demonstrated in the Fc-BDP-C60 triad and [Fc]2-BDP-C60 tetrad by femtosecond transient absorption studies. 相似文献
59.
John C. Heckel Fatimah F. Farhan George Chumanov 《Colloid and polymer science》2008,286(13):1545-1552
Carbon nanoparticles between 10 and 50 nm in diameter and carbon shells of various thickness around silver nanoparticles were
synthesized by the hydrothermal reaction of fructose. The effect of the carbon shells on the plasmon resonance of the silver
nanoparticles and their stability in sodium chloride solutions was investigated. The shell thickness can be adjusted to have
insignificant damping of the plasmon resonance and provide stabilization of the particles in solutions with high ionic strength.
Hydrazine–carbonyl cross-linking reactions were performed to link fluorescent dye molecules to carbonyl groups on the carbon
shell surface. 相似文献
60.