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81.
Kattakgoundar Govindaraj Sudha Saheb Ali Gopalu Karunakaran Mariyappan Kowsalya Evgeny Kolesnikov Mohan Prasanna Rajeshkumar 《应用有机金属化学》2020,34(4):e5511
The tunable ZnO nanorods (NRs) are produced due to the phytochemicals present in Cycas pschannae leaves which act as reducing and stabilizing agents. The confirmations of the ZnO NRs were validated using different characterization techniques: X-ray diffraction, Fourier transform infrared spectroscopy, Brunauer, Emmett and Teller (BET), scanning electron microscopy–Energy Dispersive X-Ray Analysis (EDX), UV–visible spectroscopy, Raman spectroscopy, and transmission electron microscopy. The ZnO NRs show unique surface area and low particle size. Photocatalytic activity was measured and found to be 50.75% at low concentrations and 78.33% at high concentrations. The antioxidant activity of the ZnO NRs also showed promising results for their use in free radical scavenging. In vitro toxicity studies using zebrafish embryos was performed to evaluate the toxic nature of it and the obtained result confirmed its non-toxic nature. In addition, ZnO anticancer potential was verified using the A549 lung cancer cell line. Cytotoxic assessments of ZnO NRs were performed via 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and neutral red uptake assays to examine the cell death cycle on the A549 lung cancer cell. Dose-dependent apoptosis and necrosis were confirmed by Lactate dehydrogenase (LDH) assay. It was also confirmed that ZnO NRs induce Reactive oxygen species (ROS) and apoptosis inside cancer (A549) cells via different intrinsic gene expression. Thus, based on this research it is evident that an effective ecofriendly, nontoxic potential anticancer drug can be synthesized using C. pschannae leaf extract. 相似文献
82.
Jhansi Rani Sunkara Sathish Mohan Botsa 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):392-400
Russian Journal of Physical Chemistry A - Recently the researchers have shown great interest on photocatalysis, especially in dyes degradation by nanocomposites under visible light. In this work,... 相似文献
83.
Mohanad A. Hussein Dr. Uyen P. N. Tran Dr. Vien T. Huynh Dr. Junming Ho Dr. Mohan Bhadbhade Prof. Dr. Herbert Mayr Dr. Thanh V. Nguyen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(4):1471-1475
Tropylium bromide undergoes noncatalyzed, regioselective additions to a large variety of Michael acceptors. In this way, acrylic esters are converted into β-bromo-α-cycloheptatrienylpropionic esters. The reactions are interpreted as nucleophilic attack of bromide ions at the electron-deficient olefins and the approach of the tropylium ion to the incipient carbanion. Quantum chemical calculations were performed to elucidate the analogy to the amine- or phosphine-catalyzed Rauhut–Currier reactions. Subsequent synthetic transformations of the bromo-cycloheptatrienylated adducts are reported. 相似文献
84.
85.
Kapil Mohan Saini Rakesh K. Saunthwal Sushmita Akhilesh K. Verma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1017-1021
Transition-metal-free regioselective synthesis of functionalized amino-indenones by the reaction of ortho-alkynylaldehydes with a broad range of primary amines by intramolecular cyclization has been described. The designed reaction proceeds through KOH-mediated Prins-type cyclization and DMSO-promoted oxidation of the cyclopent-2-en-1-one system. The proposed mechanism and role of solvent were well supported by control experiments. For the first time, we have disclosed the reverse reactivity of (2-alkynyl)-arylaldimines in a super basic system. 相似文献
86.
Shaik A. Rao A. T. Venkatarao D. V. Rao S. V. M. Mohan Kishore P. V. V. N. 《Russian Journal of Organic Chemistry》2020,56(12):2179-2187
Russian Journal of Organic Chemistry - A series of novel 1,2,4-triazole nonsteroidal anti-inflammatory drugs (NSAIDs) derived from etodolac were designed and synthesized. The synthesized compounds... 相似文献
87.
Lakhwant Singh Mohan Singh Bikram Singh Navjeet Kaur 《Indian Journal of Physics》2009,83(8):1109-1115
A comparative study of stopping power codes for different ions in compounds has been made by comparing the computed stopping
power values using different codes with the corresponding experimental data. Two computer codes, semiempirical SRIM2006.02
and theoretical CasP3.2 have been used to evaluate and compare the stopping powers of different compounds for protons (125
KeV), helium (500 KeV) and lithium ion (175 KeV) projectiles. The energy behaviour of stopping power of various compounds
for helium ion in the energy range (0.3–2.0 MeV) has been studied. The merits and demerits of the adopted formulations are
highlighted. It has been observed that the calculation based on SRIM2006.02 provides the best agreement with the experimental
data as compared to CasP3.2 code. The stopping power contribution due to target and projectile excitation/ionization at low
energies has been evaluated and discussed with reference to CasP3.2 code. From these comparative studies it has been concluded
that the target and projectile excitation-ionization increases the stopping power (>20%) at lower energies. 相似文献
88.
Mohan K. Kadalbajoo Puneet Arora 《Numerical Methods for Partial Differential Equations》2010,26(5):1206-1223
The advection‐diffusion equation has a long history as a benchmark for numerical methods. Taylor‐Galerkin methods are used together with the type of splines known as B‐splines to construct the approximation functions over the finite elements for the solution of time‐dependent advection‐diffusion problems. If advection dominates over diffusion, the numerical solution is difficult especially if boundary layers are to be resolved. Known test problems have been studied to demonstrate the accuracy of the method. Numerical results show the behavior of the method with emphasis on treatment of boundary conditions. Taylor‐Galerkin methods have been constructed by using both linear and quadratic B‐spline shape functions. Results shown by the method are found to be in good agreement with the exact solution. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010 相似文献
89.
The evolution of nonlinear Langmuir waves in the interplanetary medium is investigated by appropriately accounting for the
random density irregularities of the medium. A pair of modified Zakharov equations, which describe these waves, is solved
numerically as an initial value problem for large scale (≫ 102 km) initial pertubations. For an ion acoustic-Langmuir solitary wave, the random irregularities damp the Langmuir wave by
way of scattering and let the ion density perturbation radiate away in a few days. However an initial solitary or shock-like
Langmuir wave excites the ion density perturbations within a fraction of a second, and then itself gets damped. These effects
will strongly decelerate the collapse of large scale Langmuir waves. The possibility of detecting these processes, by means
of interplanetary scintillation, is discussed.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
90.
A λ‐design is a family ?? = {B1, B2, …, Bv} of subsets of X = {1, 2, …, v} such that |Bi∩Bj| = λ for all i≠jand not all Bi are of the same size. The only known example of λ‐designs (called type‐1 designs) are those obtained from symmetric designs by a certain complementation procedure. Ryser [J Algebra 10 (1968), 246–261] and Woodall [Proc London Math Soc 20 (1970), 669–687] independently conjectured that all λ‐designs are type‐1. Let g = gcd(r ? 1, r* ? 1), where rand r* are the two replication numbers. Ionin and Shrikhande [J Combin Comput 22 (1996), 135–142; J Combin Theory Ser A 74 (1996), 100–114] showed that λ‐designs with g = 1, 2, 3, 4 are type‐1 and that the Ryser–Woodall conjecture is true for λ‐designs on p + 1, 2p + 1, 3p + 1, 4p + 1 points, where pis a prime. Hein and Ionin [Codes and Designs—Proceedings of Conference honoring Prof. D. K. Ray‐Chaudhuri on the occasion of his 65th birthday, Ohio State University Mathematical Research Institute Publications, 10, Walter de Gruyter, Berlin, 2002, pp. 145–156] proved corresponding results for g = 5 and Fiala [Codes and Designs—Proceedings of Conference honoring Prof. D. K. Ray‐Chaudhuri on the occasion of his 65th birthday, Ohio State University Mathematical Research Institute Publications, 10, Walter de Gruyter, Berlin, 2002, pp. 109–124; Ars Combin 68 (2003), 17–32; Ars Combin, to appear] for g = 6, 7, and 8. In this article, we consider λ designs with exactly two block sizes. We show that in this case, the conjecture is true for g = 9, 11, 12, 13, 15, 16, 17, 19, 20, 21, and for g = 10, 14, 18, 22 with v≠4λ ? 1. We also give two results on such λ‐designs on v = 9p + 1 and 12p + 1 points, where pis a prime. © 2010 Wiley Periodicals, Inc. J Combin Designs 19:95‐110, 2011 相似文献