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61.
Murugavel Saminathan Saranya Kanagarajan Ravikumar Chandrasekaran Archana Sivasubramaniyan Ranganathan Raja Ponnusamy Alagusundaram 《中国化学会会志》2020,67(6):1100-1112
Two novel compounds 1-(5-[4-fluorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (FSCN) and 1-(5-[4-chlorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (ClSCN) were synthesized and characterized by SC-XRD, 1H NMR, 13C NMR, FTIR, and UV methods. The X-ray diffraction studies were utilized to prove the 3D crystal structures of FSCN and ClSCN. In both the compounds, the packing is mostly driven by C H⋯N, C H⋯O, and C H⋯π (benzene ring as an acceptor) interactions. In ClSCN, additionally, the π⋯π interaction is observed between the pyrazole ring of one molecule and the benzene ring of the other molecule. The experimental values were compared with the results of DFT/B3LYP/6-311G++(d,p) theoretical computations. The pharmacological screening for FSCN and ClSCN was performed using molinspiration and PreADMET web server. To analyze antibacterial inhibition of the synthesized ligands and Ciprofloxacin (control drug) were interacted with antibacterial protein Thymidylate Kinase (TMK) (PDB ID: 4QGG) with the help of AutoDock Vina tool. The ADMET and docking results of FSCN and ClSCN pointed out the better drug likeness nature and good inhibition behavior with TMK protein. The antibacterial in vitro studies suggested that FSCN compound inhibited well with antibacterial strains than that of ClSCN. The current investigation suggests that with further improvements, our compounds could be preferred as substitute medicine for bacterial diseases. 相似文献
62.
In this paper, our aim is to show some mean value inequalities for the modified Bessel functions of the first and second kind. Our proofs are based on some bounds for the logarithmic derivatives of these functions, which are in fact equivalent to the corresponding Turán-type inequalities for these functions. As an application of the results concerning the modified Bessel function of the second kind, we prove that the cumulative distribution function of the gamma–gamma distribution is log-concave. At the end of this paper, several open problems are posed, which may be of interest for further research. 相似文献
63.
The Fourier transform infrared (FTIR) spectral analysis has been carried out for sediments of Vellar river, Tamilnadu collected
at various depths from twenty seven different locations. The minerals such as quartz, feldspar (microcline and orthoclase),
kaolinite, palygorskite, calcite, aragonite, montmorillonite, cerussite, hematite, sepiolite, magnesium oxalate and organic
carbon are identified. Among these, quartz, feldspar and kaolinite are the major minerals and palygorskite, calcite, aragonite,
montmorillonite, cerussite, hematite, sepiolite, magnesium oxalate and organic carbon are minor and traces. The relative distribution
of these three major minerals was determined by computing the extinction co-efficient. The crystalline nature of quartz is
judged by calculating crystallinity index which shows that the crystalline nature decreases with increase of depth. The observation
made through relative distribution, shows that the amount of quartz and feldspar are relatively reduced and that of kaolinite
is increased from upper to inner depth. As the depth increases the bands of kaolinite progressively broaden and shift to higher
wave number side which suggests that the content of kaolinite increases with disorderedness. From XRD analysis, the minerals
such as monazite, zircon and kyanite are additionally identified. The crystalline nature of quartz is also confirmed. 相似文献
64.
In this paper, we investigate Clunie and Sheil-Small’s covering theorems for sense-preserving planar harmonic univalent mappings defined in the unit disk. Our results significantly improve the earlier known result. Also, we obtain a distortion theorem for fully starlike harmonic mappings in the unit disk. 相似文献
65.
M. Okada S. Ponnusamy A. Vasudevarao H. Yanagihara 《Mathematische Nachrichten》2016,289(8-9):1044-1051
We study the class of univalent analytic functions f in the unit disk of the form satisfying where Ω will be a proper subdomain of which is starlike with respect to . Let be the unique conformal mapping of onto Ω with and and . Let denote the arclength of the image of the circle , . The first result in this paper is an inequality for , which solves the general extremal problem , and contains many other well‐known results of the previous authors as special cases. Other results of this article cover another set of related problems about integral means in the general setting of the class . 相似文献
66.
In this paper, we prove necessary and sufficient conditions for a sense-preserving harmonic function to be absolutely convex in the open unit disc. We also estimate the coefficient bound and obtain growth, covering and area theorems for absolutely convex harmonic mappings. A natural generalization of the classical Bernardi-type operator for harmonic functions is considered and its connection between certain classes of uniformly starlike harmonic functions and uniformly convex harmonic functions is also investigated. At the end, as applications, we present a number of results connected with hypergeometric and polylogarithm functions. 相似文献
67.
68.
Let ${\mathcal H}$ be the class of complex‐valued harmonic functions in the unit disk |z| < 1 and ${\mathcal H}_1$ the set of all functions $f\in {\mathcal H}$ such that f(0) = 0, fz(0) = 1 and $f_{\overline{z}}(0)=0$. For $V \subset {\mathcal H}_1$, its dual V* is where * denotes the Hadamard product for harmonic functions. The set V is a dual class if V = W* for some $W \subset {\mathcal H}_1.$ In the present paper, the duality principle is extended to ${\mathcal H}_1$ by means of the Hadamard product. Counterparts of the dual classes are introduced and their structural properties studied. 相似文献
69.
Iigiz R. Kayumov Saminthan Ponnusamy Le Anh Xuan 《Complex Analysis and Operator Theory》2018,12(5):1291-1301
In this article we obtain two sharp results concerning the analytic part of harmonic mappings \(f=h+\overline{g}\) from the class \(\mathcal {S}^0_H(\mathcal {S})\) which was recently introduced by Ponnusamy and Sairam Kaliraj. For example, we get the sharp estimate for \(|\arg h'(z)|\) in the case when \(|z| \le 1/\sqrt{2}\) and obtain the sharp radius of convexity for h. Our approach is applicable to a more general situation. Finally, we determine simple condition on the analytic part of univalent harmonic mappings so that it is in \(H_p\) spaces for \(0<p<1/3\). 相似文献
70.
Based on the Borel transformation and the Hadamard multiplication theorem on singularities on the convolution of holomorphic
functions, results on the growth of entire functions defined by convolution of an entire function of exponential type with
a function holomorphic at the origin are obtained.
Received: 29 August 2005 相似文献