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排序方式: 共有174条查询结果,搜索用时 15 毫秒
151.
S.P.N. Sudhan R. Nasir Ahmed H. Kiyani S. Sheik Mansoor 《Journal of Saudi Chemical Society》2018,22(3):269-278
A simple, green and environmentally benign procedure was developed for the one pot synthesis of 3-methyl-1,4-diphenyl-1,4,5,7-tetrahydro-pyrazolo[3,4-d]pyrimidine-6-one/thiones using catalytic amount of phthalimide-N-sulfonic acid (PISA) in 1-butyl-3-methylimidazolium bromide ([Bmim][Br]) ionic liquid via the three-component reaction of 1-phenyl-3-methyl-1H-pyrazole-5(4H)-one, aromatic aldehyde and urea/thiourea. [Bmim][Br] as reaction media offers several advantages including non-toxic, non-corrosive, shorter reaction times, high yield of the products, mild reaction conditions as well as simple experimental and isolation procedures. 相似文献
152.
Dr. Georgios Pantouris Dr. Junming Ho Dr. Dilip Shah Dr. Mansoor Ali Syed Dr. Lin Leng Prof. Vineet Bhandari Prof. Richard Bucala Prof. Victor S. Batista Prof. J. Patrick Loria Prof. Elias J. Lolis 《Angewandte Chemie (International ed. in English)》2018,57(24):7116-7119
Macrophage migration inhibitory factor (MIF) activates CD74, which leads to severe disorders including inflammation, autoimmune diseases and cancer under pathological conditions. Molecular dynamics (MD) simulations up to one microsecond revealed dynamical correlation between a residue located at the opening of one end of the MIF solvent channel, previously thought to be a consequence of homotrimerization, and residues in a distal region responsible for CD74 activation. Experiments verified the allosteric regulatory site and identified a pathway to this site via the MIF β‐strands. The reported findings provide fundamental insights on a dynamic mechanism that controls the MIF‐induced activation of CD74. 相似文献
153.
Seik Mansoor Ali Vasudevan Raghavan Ali S. Rangwala 《Combustion Theory and Modelling》2013,17(4):495-518
A numerical study of laminar diffusion flames established over a condensed fuel surface, inclined at several angular orientations in the range of –90°?θ?+90° with respect to the vertical axis, under atmospheric pressure and normal gravity environment, is presented. Methanol is employed as the fuel. A numerical model, which solves transient gas-phase, two-dimensional governing conservation equations, with a single-step global reaction for methanol–air oxidation and an optically thin radiation sub-model, has been employed in the present investigation. Numerical results have been validated against the experimental data from the present study. Thereafter, the model is used to investigate the influence of angular orientation of fuel surface on its quasi-steady burning characteristics. Results in terms of fuel mass burning rate, flame stand-off distances, temperature field, velocity profiles and oxygen contours have been presented and discussed in detail. It is observed that orientation angles in the range of –45°?θ? –30° (fuel surface facing upwards), yield the maximum mass burning rates. The flame anchoring location near the leading edge of the fuel surface, normal gradient of fuel vapor mass fraction at the surface and oxygen contours have been used to explore this unique behavior. Based on the numerical results, a theoretical correlation to predict the mass burning rate as a function of fuel surface orientation is also proposed. Furthermore, a discussion on the differences in the structure of laminar diffusion flame established over fuel surface as a function of its angular orientation is included. 相似文献
154.
Mansoor H. Alshehri Barry J. Cox James M. Hill 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2013,67(11):1-9
We study analytically the properties of the optical absorption and the spatial weak-light solitons in a quantum dot molecule system with the interdot tunneling coupling (ITC). It is shown that, for the linear case, there exists tunneling induced transparency (TIT) in the context of a weak ITC, while the TIT can be replaced by Autler-Townes splitting in the presence of a strong ITC. For the nonlinear case, it is probable to realize the spatial optical solitons even under weak light intensity. Interestingly, we find that there appears transformation behavior between the bright and dark solitons by properly turning both the ITC strength and the detuning of the probe field. Meanwhile, the transformation condition of the bright and dark solitons is obtained. Additionally it is also found that the amplitude of the solitons first descends and then rises with the increasing of ITC strength. Our results may have potential applications for nonlinear optical experiments and optical telecommunication engineering in solid systems. 相似文献
155.
ABSTRACTThe blue phase of YBa2Cu3O7- δ (YBCO) family, Y2Cu2O5 (Y202) nanoparticles were prepared and doped into (YBCO) superconductor and the effect of doping on critical current density and critical temperature was investigated. Y202 nanoparticles with particle sizes of 47, 107 and 206?nm were prepared by a sol–gel combustion method and added into the YBCO superconductor by 0.5–2?wt.%. XRD and scanning electron microscope measurements were used to characterize the samples. The measurement of critical current density at 77?K revealed that the doped superconductors had larger critical current density compared to the undoped superconductors. For a fixed dopant concentration, by increasing the size of nanoparticles, the Jc was increased. For the samples including 0.5?wt.% of nanoadditives, Jc was higher. The highest critical current density of 137?A/cm2 was measured for the superconductors containing 0.5?wt.% of 206?nm Y202 nanoparticles. Also, by increasing the nanoparticles concentration, the Tc was reduced. 相似文献
156.
Research on Chemical Intermediates - Iron oxide (Fe3O4) and copper-functionalized silicon nanowires (SiNWs) from silicon powder mesh?<?500 with a spherical structure have been... 相似文献
157.
To-date, all experiments switching perpendicular magnetic anisotropy (PMA) materials with in-plane spin polarization require external B-fields. Here, in two approaches, it is shown that with Rashba-type in-plane spin polarization and PMA, bistable switching is achievable without external B -fields, and at currents on the order of 107 A/cm2, consistent with recent experiments. Utilization of PMA is primarily discussed, demonstrating the potential for two possibilities: (1) in-plane polarization as a ‘natural’ candidate for precessional switching and (2) bistable switching using a tilted anisotropy axis. Both are shown to lead to stable perpendicular switching without an external B-field, even though spin polarization is in-plane. 相似文献
158.
A high‐resolution accurate mass (HR/AM) approach to identification,profiling and characterization of in vitro nefazodone metabolites using a hybrid quadrupole Orbitrap (Q‐Exactive) 下载免费PDF全文
Simon J. Perry Szilárd Nász Mansoor Saeed 《Rapid communications in mass spectrometry : RCM》2015,29(17):1545-1555
159.
160.
The acidity of different classes of organic compounds in aqueous solution has been calculated. The calculations are carried out at the SCF level with inclusion of entropic and thermochemical correction to yield free energies of dissociations.
The polarized continuum model is used to describe the solvent. The model furnishes pKa values in relatively good agreement with experimental data. Scaling different parts of solvation energies provides a significant improvement in results and signifies the importance of balance of individual contributions from electrostatic, cavity, dispersion and repulsion interactions. 相似文献