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761.
Bhavani Palagiri Rajababu Chintaparty Venkata subbha Reddy Imma Reddy 《Phase Transitions》2017,90(6):578-589
The iron oxide nanoparticles were synthesized by a simple hydrothermal method at different heating temperatures and pH conditions. The synthesized materials were characterized by X-ray diffractometer, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, UV–visible spectrometer and vibrating sample magnetometer. With increment in pH of the synthesized materials were resulted in orthorhombic (goethite) and cubic (magnetite) structures at pH 6 and 12, respectively. The banding nature of synthesized materials was analyzed by infrared spectra. The synthesized powders at 130?°C showed higher percent of nanorods (length = 90–120 nm) in addition to lower percentage of nanoparticles. The material at pH 12 consisted of maximum nanoparticles with size = 10–60 nm with small agglomerations. Band gap energy of synthesized materials was 2.2–2.8 eV. Herein, the reaction conditions tuned the saturation magnetization (MS). The maximum MS (59.38 emu/g) was obtained at pH 12 and lower MS (0.65 emu/g) was observed at pH 6 due to intrinsic property of goethite phase. 相似文献
762.
Vijay Kumar Reddy Avula Venkata Ramaiah Chintha Swetha Vallela Jaya Shree Anireddy Naga Raju Chamarthi Rajendra Wudayagiri 《Journal of heterocyclic chemistry》2019,56(1):209-217
An efficient method has been developed for the synthesis of N‐alkylated 2′‐oxo‐3‐phenylspiro[cyclopropane‐1,3′‐indoline]‐2,2‐dicarbonitrile from 3‐chloroindolin‐2‐one and 2‐benzylidenemalononitrile by using triethylamine as a base at room temperature and obtained the products in moderate to good yields. In extension, the scope of the reaction has been investigated by stepwise and one‐pot methods. Furthermore, in silico antibacterial activity was carried out in order to understand possible binding modes of novel derivatives with the active site of DNA gyrase A enzyme, and the results were well complemented. Additionally, absorption, distribution, metabolism, and excretion properties of compounds have shown drug likeness with good oral absorption and moderate blood–brain barrier permeability. 相似文献
763.
Suresh Narva Surendar Chitti Suresh Amaroju Sridhar Goud Mallika Alvala Debanjan Bhattacharjee Nishant Jain Chandra Sekhar Kondapalli Venkata Gowri 《Journal of heterocyclic chemistry》2019,56(2):520-532
A series of 28 novel 2‐(4‐aminophenyl)benzothiazole analogues have been synthesized and characterized using various analytical techniques like 1H NMR, 13C NMR, electrospray ionization mass spectrometry, and IR and bioevaluated for their antiproliferative activity over a group of three human cancer cell lines, namely, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MDA‐MB‐231), using sulforhodamine B assay method. Few synthesized molecules ( 5a , 5c , 5d , 5f , 7b , and 7j ) displayed effective growth inhibition (GI50) activity against the tested human cancer cell lines at lower micromolar concentration (GI50) values in the range 0.2–1.7 μM. Noticeably, compound 7b exhibited reasonable activity in all three cancer cell lines in the GI50 range 0.55–1.2 μM. Further, when 7b was screened for tubulin polymerization inhibition, it exhibited more than 55% inhibition at concentration of 5.0 μM. The molecular docking simulations supported the molecular interactions of the derivatives with the targeted receptor. These derivatives may serve as lead structures for development of potential anticancer drug candidates, and 7b might act as a potential microtubule polymerization inhibitor. 相似文献
764.
Ramakrishnam Raju Addada Venkata Reddy Regalla Sivarami Reddy Gangireddy Venkata Venkata Naresh Vema Venkateswara Rao Anna 《Journal of heterocyclic chemistry》2019,56(3):815-817
A stereoselective total synthesis of parvistone C, an oxygenated natural styryllactone, has been accomplished in excellent overall yield by employing asymmetric aldol reaction, asymmetric epoxidation and regioselective epoxide ring opening as the key steps. Our synthetic strategy is very simple, concise and no use of protecting groups. 相似文献
765.
A chiral pool approach starting with d-glucose, using the Yamaguchi protocol and a Z-selective HWE reaction followed by lactonization, has been applied to execute the total synthesis of strictifolione. 相似文献
766.
Fixed Point Theorems on Chain Complete Partially Ordered Sets 总被引:1,自引:0,他引:1
In this paper, we extend the results of Tarski, Abian and Brown on the completeness of lattices by fixed point theorems, to partially ordered sets or (Po sets) with chain completeness property. We also sharpen some of the existing results on completeness of lattices and fixed-point theorems. We also provide counter examples to some of the claims of R. Taskovic to disprove his theorem.Milan R. Taskovic claims to have proved this theorem but his proof is based on a false argument. In fact most of the contentions of Milan R. Taskovic in [4] are factually incorrect. Actually, reviewer of Taskovics paper has pointed out some of his inaccurate observations. See Mathematical Reviews No. 90b:06007, 06A10. 相似文献
767.
Ramana CV Baquer SM Gonnade RG Gurjar MK 《Chemical communications (Cambridge, England)》2002,(6):614-615
Synthesis of tetrakis(cyclopropylmethyl)methane, a new symmetric product has been described using the radical mediated gem-diallylation of cyclopropylmethyl xanthate as a key step and its single crystal X-ray analysis established its C2-symmetry. 相似文献
768.
Air‐breathing propulsion systems for high‐speed space travel applications are studied. Ramjets and scramjets have been identified as potential candidates. The flow inlets of such systems are modelled with a simulation that can predict all complex inlet flow features, including shock due to forebody, multiple shock reflections, normal shock, shock–boundary layer interaction and associated separation for two‐dimensional and axisymmetric inlets. Computed values are in good agreement with experimental data. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
769.
770.
Exact solutions of the Navier-Stokes equations are derived by a Laplace-transform technique for two-dimensional, incompressible flow of an electrically conducting fluid past an infinite porous plate under the action of a transverse magnetic field subject to the conditions: (i) the magnetic Prandtl number Pm is unity, and (ii) the Alfven velocity is less than the suction velocity. It is assumed that the flow is independent of the distance parallel to the plate and that the velocity component normal to the plate is constant. General formulae are derived for the velocity distribution and the magnetic field in terms of the given external velocity. The skin-friction is obtained and some special cases are considered. 相似文献