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81.
Dhananjay Bhattacherjee Shankar Ram Arvind Singh Chauhan Yamini Sheetal Dr. Pralay Das 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(23):5934-5939
A highly efficient and flexible protocol for intramolecular annulation of exocyclic β-enaminones has been disclosed for the synthesis of carbazolones and imidazo[1,2-a]pyridines through a counter-anion-controlled free-radical mechanism promoted by hypervalent iodine(III). The cooperative behavior of HTIB and AgSbF6 plays a crucial role in the intramolecular annulation process through C−C and C−N bond formation to give the desired products. The mechanistic insights suggest that the two competitive reactions involved in the system are guided by the nature of the counteranion, which determines the formation of the final products. A wide variety of carbazolones and imidazo[1,2-a]pyridine molecules have been prepared and isolated in good to excellent yields. 相似文献
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Manish Choudhary Sandesh Kumar Jain G.L. Devnani Shri Ram S. Sonawane Dhananjay Singh 《印度化学会志》2022,99(5):100444
Agro waste bio mass are creating challenges for environment in term of air pollution due to improper disposal. Rice milling is the process in which rice husk is produced as by-product. The agro-waste rice husk has tremendous potential to be used either in its raw form or in ash form. The inherent component of this waste cellulose provides enhanced properties in a reinforced composite when used as filler. Rice husk is the hard outer layer and covering rice seed, which makes reinforcement challenging in its original form. Fiber surface treatment significantly improves adhesion with matrix and various thermo chemical properties of filler as well as of composites. NaOH treatment is cost-effective and it ensures the adhesion with matrix by removal of hemicellulose and lignin. The chemical treatment of agro-waste (rice husk) is performed with 5% alkali solutions of NaOH in water. Results are compared with the properties of untreated rice husk for thermal and morphological characterizations. In the present work, we are trying to quantify the impact of chemical treatment on rice husk thermal decomposition and its kinetics. Thermogravimetric analysis and kinetics study of thermal degradation, provide key input towards pyrolysis pattern of rice husk, while FTIR and SEM analysis provide the prospects of this bio filler using a reinforcing agent to develop green composite and productive disposal. The FTIR data helps to find the possibilities of blending different bio fillers and natural fibers to find suitable reinforcing substances. The average activation energy of treated fiber is noted as 137.95 by KAS method and 108.08 by FWO method as compared to 55.56 by KAS method & 54.26 by FWO method for untreated rice husk. 相似文献
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Kulkarni Ulka K. Kulkarni Krishna V. Pardeshi Rajendra K. Mane Dhananjay V. 《平面色谱法杂志一现代薄层色谱法》2016,29(5):391-393
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
84.
Santosh M Panigrahi S Bhattacharyya D Sood AK Maiti PK 《The Journal of chemical physics》2012,136(6):065106
In an effort to design efficient platform for siRNA delivery, we combine all atom classical and quantum simulations to study the binding of small interfering RNA (siRNA) by pristine single wall carbon nanotube (SWCNT). Our results show that siRNA strongly binds to SWCNT surface via unzipping its base-pairs and the propensity of unzipping increases with the increase in the diameter of the SWCNTs. The unzipping and subsequent wrapping events are initiated and driven by van der Waals interactions between the aromatic rings of siRNA nucleobases and the SWCNT surface. However, molecular dynamics (MD) simulations of double strand DNA (dsDNA) of the same sequence show that the dsDNA undergoes much less unzipping and wrapping on the SWCNT in the simulation time scale of 70 ns. This interesting difference is due to smaller interaction energy of thymidine of dsDNA with the SWCNT compared to that of uridine of siRNA, as calculated by dispersion corrected density functional theory (DFT) methods. After the optimal binding of siRNA to SWCNT, the complex is very stable which serves as one of the major mechanisms of siRNA delivery for biomedical applications. Since siRNA has to undergo unwinding process with the effect of RNA-induced silencing complex, our proposed delivery mechanism by SWCNT possesses potential advantages in achieving RNA interference. 相似文献
85.
Nandi D Prabhudesai VS Nestmann BM Krishnakumar E 《Physical chemistry chemical physics : PCCP》2011,13(4):1542-1551
An experimental and theoretical investigation of the dissociative electron attachment process in nitric oxide is presented. Measurements using the recently developed ion momentum imaging conclusively show the presence of two resonance features in the O(-) channel. These are found to dissociate to give N atoms in the (2)D and (2)P excited states respectively, thus settling the controversies regarding the possible dissociation limits of this process. Though the angular distribution of O(-) shows the resonances contributing to these dissociations are of Π symmetry and a mixture of Π and Σ or Δ symmetry respectively, our calculations using R-matrix theory show no direct electron attachment channel leading to O(-) through these resonances, as all the allowed resonances below 10 eV decay to either O + N(-) or O(-) + N((4)S) channels. We propose that indirect mechanisms through curve crossings lead to the experimentally observed results. 相似文献
86.
Dissociative electron attachment to SO2, NO2, NF3 and H2O2 is studied in terms of the kinetic energies of the dominant fragment ions. The O? data from SO2 show that the two major resonances at 4.6 and 7.2 eV respectively have the same dissociation limit. Similarly, the resonances at 1.8 and 3.5 eV in the O? channel in NO2 appear to have same dissociation limit of NO (X 2Π) + O?, while the resonance at 8.5 eV appears to dissociate to give NO (a 4Πi) along with O?. We find considerable internal excitation of the neutral fragments in all these cases along with that of NF3, whereas the negative ion resonance in H2O2 appears to fragment almost like a diatomic system with very little internal excitation of the OH and OH? fragments. 相似文献
87.
Asef Nazari Dhananjay Thiruvady Aldeida Aleti Irene Moser 《The Journal of the Operational Research Society》2016,67(8):1050-1060
Component deployment is a combinatorial optimisation problem in software engineering that aims at finding the best allocation of software components to hardware resources in order to optimise quality attributes, such as reliability. The problem is often constrained because of the limited hardware resources, and the communication network, which may connect only certain resources. Owing to the non-linear nature of the reliability function, current optimisation methods have focused mainly on heuristic or metaheuristic algorithms. These are approximate methods, which find near-optimal solutions in a reasonable amount of time. In this paper, we present a mixed integer linear programming (MILP) formulation of the component deployment problem. We design a set of experiments where we compare the MILP solver to methods previously used to solve this problem. Results show that the MILP solver is efficient in finding feasible solutions even where other methods fail, or prove infeasibility where feasible solutions do not exist. 相似文献
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Structural Chemistry - Non-invasive imaging of amyloid beta (Aβ) and tau fibrils in the brain may support an early and precise diagnosis of Alzheimer’s disease. Molecular imaging... 相似文献