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61.
Fatima Javed Saqib Ali Saira Shahzadi Nasir Khalid Saira Tabassum Imran Khan Saroj K. Sharma Kushal Qanungo 《中国化学会会志》2015,62(8):728-738
New organotin(IV) complexes have been synthesized by treating potassium o‐isopropyl carbonodithioate with R2SnCl2/R3SnCl in 1 : 2/1 : 1 M/L ratio. All complexes have been characterized by IR and NMR (1H, 13C) spectroscopy. IR results shows that ligand acts as bidentate which is also confirmed by semi‐empirical study. NMR data reveals four coordinated geometry in solution. Computed positive heat of formation shows that complex 5 is thermodynamically unstable. UV/visible spectroscopy was used to assess the mode of interaction and binding of the complexes with DNA which shows that complex 5 exhibits higher binding constant as compared to complex 3 . In protein kinase inhibition assay, compound 3 was found most active, while other biological activities shows that triorganotin(IV) complexes are biologically more active as compared to diorganotin(IV) complexes. 相似文献
62.
Varish Ahmad Qazi Mohammad Sajid Jamal Arun K. Shukla Javed Alam Ahamad Imran Usama Mohamed Abaza 《Journal of Cluster Science》2017,28(4):1775-1802
The search of eco-friendly technologies for nano-synthesis is significant to expand their applications in human welfare. Nowadays, various inorganic nanoparticles with beneficial features have been synthesized via physical, chemical, and biological means. Significant biological applications of silver nanoparticles include on-infectious microbes, target drug delivery, cancer and vector-borne disease control. Their syntheses have been tested from plant fungi, bacteria, and viruses. The bacterial mediated synthesis of silver, gold, zinc and other metal leads to a milestone in nano-medicines. Thus, in this review, we focus on the contribution of Bacilli in the synthesis of silver nanoparticles, the mechanism of action and their potential application in the welfare of human beings. 相似文献
63.
Wei Gao Muhammad Imran Abdul Qudair Baig Haidar Ali Mohammad Reza Farahani 《Journal of Applied Mathematics and Computing》2017,55(1-2):99-117
In QSAR/QSPR study, physico-chemical properties and topological indices such as Randi?, atom-bond connectivity (ABC) and geometric-arithmetic (GA) index are used to predict the bioactivity of chemical compounds. A topological index is actually designed by transforming a chemical structure into a numeric number. These topological indices correlate certain physico-chemical properties like boiling point, stability, strain energy etc. of chemical compounds. Graph theory has found a considerable use in this area of research. The topological indices of certain interconnection networks were studied recently by Imran et al. (Appl Math Comput 244:936–951, 2014). In this paper, we extend this study to \(n\times n\) Sudoku graphs and derive analytical closed results of general Randi? index \(R_{\alpha }(G)\) for different values of “\(\alpha \)” for Sudoku (SK). We also compute the general Randi?, first Zagreb, ABC, GA, \(ABC_{4}\) and \(GA_{5}\) indices and give closed formulae of these indices for Sudoku graphs. 相似文献
64.
Mohd. Imran Ansari Ravi Shankar Mohd. Kamil Hussain Ruchir Kant Prakash R. Maulik K. Ravi Kumar K. Hajela 《Journal of heterocyclic chemistry》2011,48(6):1336-1341
Mono‐ and bis‐diaryl‐2H‐1,4‐benzothiazines were obtained in quantitative yields through silica‐supported perchloric acid catalyzed reaction cascade of double condensation and 1,4 addition of diaroylacetylenes with 2‐aminothiophenol at room temperature. The structures were confirmed by spectroscopic analyses and X‐ray crystallographic studies. J. Heterocyclic Chem., (2011) 相似文献
65.
Javed Iqbal Feroza Hamid Wattoo Muhammad Hamid Sarwar Wattoo Rukhsana Malik Syed Ahmad Tirmizi Muhammad Imran Allah Bux Ghangro 《Arabian Journal of Chemistry》2011,4(4):389-395
Chitosan flakes, extracted from prawns and labeo rohita scales, with high adsorption capacity were prepared after chemical treatment and were used to remove acid yellow dye from water. The results showed that adsorption capacity is dependent on pH, initial concentration of dye, BET, Langmuir surface area and pore volume of the adsorbent. In acidic conditions, the polymer amino groups were protonated (positively charged polymer chain), which showed attraction with negative ions of anionic dye. Chitosan from prawns scales showed higher dye adsorption under the same experimental conditions. Adsorption isotherms were developed and equilibrium data fitted well to Langmuir and Freundlich isotherm models. 相似文献
66.
A visco-elastoplastic model for the impact between a compact body and a composite target is presented. The model is a combination
of a nonlinear contact law that includes energy loss due to plastic deformation and a viscous element that accounts for energy
losses due to wave propagation and/or damping. The governing nonlinear equations are solved numerically to obtain the response.
A piecewise linear version of the model is also presented, which facilitates analytical solution. The model predictions are
compared to those of the well-known and commonly used Hunt–Crossley model. The effects of the various impact parameters, such
as impactor mass, velocity, plasticity, and damping, on the impact response and coefficient of restitution are investigated.
The model appears to be suitable for a wide range of impact situations, with parameters that are well defined and easily calculated
or measured. Furthermore, the resulting coefficient of restitution is shown to be a function of impact velocity and damping,
as confirmed by published experimental data. 相似文献
67.
In this paper, the velocity field and the associated tangential stress corresponding to the rotational flow of a generalized
Maxwell fluid within an infinite circular cylinder are determined by means of the Laplace and finite Hankel transforms. Initially,
the fluid is at rest, and the motion is produced by the rotation of the cylinder about its axis with a unsteady angular velocity.
The solutions that have been obtained are presented under series form in terms of the generalized G
a,b,c
(, t)-functions. The similar solutions for the ordinary Maxwell and Newtonian fluids, performing the same motion, are obtained
as special cases, when β → 1, respectively β → 1 and λ → 0, from general solutions. Finally, the solutions that have been obtained are compared by graphical illustrations,
and the influence of the pertinent parameters on the fluid motion is also underlined by graphical illustrations. 相似文献
68.
The velocity field and the adequate shear stress corresponding to the longitudinal flow of a fractional second grade fluid, between two infinite coaxial circular cylinders, are determined by applying the Laplace and finite Hankel transforms. Initially the fluid is at rest, and at time t = 0+, the inner cylinder suddenly begins to translate along the common axis with constant acceleration. The solutions that have been obtained are presented in terms of generalized G functions. Moreover, these solutions satisfy both the governing differential equations and all imposed initial and boundary conditions. The corresponding solutions for ordinary second grade and Newtonian fluids are obtained as limiting cases of the general solutions. Finally, some characteristics of the motion, as well as the influences of the material and fractional parameters on the fluid motion and a comparison between models, are underlined by graphical illustrations. 相似文献
69.
Journal of Algebraic Combinatorics - We show that the $$\gamma $$ -vector of the interval subdivision of a simplicial complex with a nonnegative and symmetric h-vector is nonnegative. In... 相似文献
70.
Yongqi Wang Tasawar Hayat Abdul Majeed Siddiqui 《Mathematical Methods in the Applied Sciences》2005,28(3):329-347
The present investigation deals with an undulating surface model for the motility of bacteria gliding on a layer of non‐Newtonian slime. The slime being the viscoelastic material is considered as a power‐law fluid. A hydrodynamical model of motility involving an undulating cell surface which transmits stresses through a layer of exuded slime to the substratum is examined. The non‐linear differential equation resulting from the balance of momentum and mass is solved numerically by a finite difference method with an iteration technique. The manner in which the various exponent values of the power‐law flow affect the structure of the boundary layer is delineated. A comparison is made of the power‐law fluid with the Newtonian fluid. For the power‐law fluid with respect to different power‐law exponent values, shear‐thinning and shear‐thickening effects can be observed, respectively. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献