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Kriti Pathak Sourav Gayen Suvam Saha Chandan Nandi Shivankan Mishra Prof. Dr. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(18):e202104393
Treatment of [Cp*RuCl2]2, 1 , [(COD)IrCl]2, 2 or [(p-cymene)RuCl2]2, 3 (Cp*=η5-C5Me5, COD= 1,5-cyclooctadiene and p-cymene=η6-iPrC6H4Me) with heterocyclic borate ligands [Na[(H3B)L], L1 and L2 ( L1 : L=amt, L2 : L=mp; amt=2-amino-5-mercapto-1,3,4-thiadiazole, mp=2-mercaptopyridine) led to the formation of borate complexes having uncommon coordination. For example, complexes 1 and 2 on reaction with L1 and L2 afforded dihydridoborate species [LAM(μ-H)2BHL] 4 – 6 ( 4 : LA=Cp*, M=Ru, L=amt; 5 : LA=Cp*, M=Ru, L=mp; 6 : LA=COD, M=Ir, L=mp). On the other hand, treatment of 3 with L2 yielded cis- and trans-bis(dihydridoborate) species, [Ru{(μ-H)2BH(mp)}2], cis- 7 and trans- 7 . The isolation and structural characterization of fac- and mer-[Ru{(μ-H)2BH(mp)}{(μ-H)BH(mp)2}], 8 from the same reaction offered an insight into the behaviour of these dihydridoborate species in solution. Fascinatingly, despite having reduced natural charges on Ru centres both at cis-and trans- 7 , they underwent hydroboration reaction with alkynes that yielded both Markovnikov and anti-Markovnikov addition products, 10 a – d . 相似文献
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Jitendra Pratap Singh Neema Agarwal Varsha Sahni Vaneet Kumar Rahul Malhotra Dinesh Pathak 《印度化学会志》2022,99(9):100581
This research intends to expand a mathematical model for studying the non-Newtonian surge of blood through a hepatic artery in the presence of steno occlusive disease post-liver transplantation. Power law liquid demonstrates the non- Newtonian character of blood. The hemodynamic conduit of the fluid is altered by the occurrence of arterial stenosis. In our study, the difficulty is resolved by applying diagnostic methods with the assistance of marginal circumstances and consequences. The outcomes are explained graphically for unusual cases for such stenosis. The study design is based on a tensorial form and converts its solution using numerical and analytical techniques. Our study outcome suitably demonstrates that the mathematical model used corroborates with the clinical scenario of the patient with hepatic disease. 相似文献
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Dark sector may couple to the Standard Model via one or more mediator particles.We discuss two types of mediators:the dark photon A’and the dark scalar mediatorΦ.The total cross-sections and various differential distributions of the processes e+e-→qqA’and e+e→qqφ(q=u,d,c,s and b quarks)are discussed.We focus on the study of the invisible due to the cleaner background at future e+e-colliders.It is found that the kinematic distributions of the two-jet system could be used to identify(or exclude)the dark photon and the dark scalar mediator,as well as to distinguish between them.We further study the possibility of a search for dark photons at a future CEPC experiment with s1/2=91.2 GeV and 240 GeV.With CEPC running at s1/2=91.2 GeV,it would be possible to perform a decisive measurement of the dark photon(20 GeV相似文献
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V.V. Sreenivasu Mummidivarapu Rakesh Kumar Pathak Vijaya Kumar Hinge Jayaraman Dessingou 《Supramolecular chemistry》2014,26(7-8):538-546
A triethylene glycol di-imine locked triazole linked bis-calix[4]arene conjugate L has been synthesised and characterised. Conjugate L exhibits high fluorescence enhancement towards Zn2+ among the 13 metal ions studied down to a lower detection limit of ~12 ppb. The absorption and visual colour change experiments differentiated the Zn2+ from the other metal ions studied. The isolated zinc complex, [Zn2L] has been used as a chemo-sensing ensemble for the recognition of anions based on their binding affinities towards Zn2+. [Zn2L] was found to be sensitive and selective towards phosphate-bearing species and in particular to adenosine triphosphate (ATP2 ? ) among the other 20 anions studied as observed based on the changes occurred in the fluorescence intensity. The selectivity of the ATP2 ? has been shown on the basis of the changes observed in the emission and absorption spectral studies. The lowest detectable concentration for ATP2 ? with the chemo-sensing ensemble [Zn2L] is 348 ppb in methanol. The fluorescence quenching by the phosphate-based anions has been modelled by molecular mechanics studies and found that the anions possessing two or more phosphate moieties can only bridge between the two zinc centres, and hence those possessing only one phosphate moiety (H2PO4? and AMP2 ? ) are ineffective. 相似文献
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V. C. Adya M. Mohapatra Nimai Pathak Mithlesh Kumar N. S. Hon S. K. Thulasidas M. J. Kulkarni V. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(1):341-346
This work presents the investigation of some commercially available and commonly used Si3N4 foils prepared with LPCVD technique. The density and the stoichiometry of these films were determined by Rutherford backscattering spectroscopy and profilometry, while the study of impurities was achieved with particle induced X-ray emission method. It was found that the density of the studied Si3N4 films is significantly less (~2.71 g cm?3), while the stoichiometry is close to the values of the bulk material. The results were verified by measuring the ion energy loss through the films by scanning transmission ion microscopy. 相似文献
9.
Quinazoline is a heterocyclic compound having biological activities. It is aromatic in nature having bicyclic structure containing benzene ring and pyrimidine ring. Quinazoline and its derivatives are found to have wide range of biological activities that is anticancer, analgesic, antimicrobial, antihypertensive, anticonvulsant, antimalarial, antitumor, and anti-tubercular activities. The purpose of this review is to highlight the recent researches made by researchers on various biological activities of quinazoline derivatives on different targets. 相似文献
10.
Using quasi-steady-state and time-resolved high-field impedance techniques, the frequency-dependent dielectric permittivity of poly(vinylacetate) has been studied at electric field amplitudes as high as 400 kV/cm. The relative changes of the dielectric loss depend quadratically on the field amplitude and reach about 1 %. The magnitude and frequency-dependence of this non-linear dielectric effect and its time evolution after applying the high field are consistent with energy absorption from the field being at the source of the non-linear behavior. Based upon a phenomenological model of heterogeneous dynamics at isothermal conditions, the observed changes can be explained by locally increased configurational temperatures and the resulting accelerated dynamics. 相似文献