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111.
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R.P. Patil S.S. Gaikwad A.N. Karanjekar P.K. Khanna G.H. Jain V.B. Gaikwad P.V. More N. Bisht 《Materials Today Chemistry》2020
In this study, we comprehensively present the gas sensing performance of strontium (Sr)-doped barium titanate (BaTiO3) nanostructures which are synthesized by a low-temperature hydrothermal route. The in-situ doping of strontium in BaTiO3 nanostructures is achieved with different molar concentrations of Sr, and the sensing performance was evaluated by screen printing process of products to form their thick films. The thick films of as-prepared Sr-doped BaTiO3 (BaSrTiO3) were investigated for gas sensing performance for various gases at different operating temperatures where strong response was observed for both nitrogen dioxide (NO2) and ammonia (NH3) gases at room temperature. Furthermore, the sensing response at room temperature for NH3 and NO2 gases was also studied with respect to Sr doping concentrations in BaTiO3 nanostructures. 相似文献
113.
Shamsan S. Obaid M. I. Sayyed D. K. Gaikwad H. O. Tekin Y. Elmahroug P. P. Pawar 《辐射效应与固体损伤》2013,168(11-12):900-914
ABSTRACTThe photon attenuation coefficients for the rocks (Feldspathic basalt, Compact basalt, Volcanic rock, Pink granite, Sandstone and Dolerite) have been investigated using MCNPX and Geant4 codes for photon energies 122, 356, 511, 662, 1170, 1275 and 1330 keV. Comparison of the simulation and experimental results of mass attenuation coefficients is presented. The exposure buildup factors also have been calculated with the help of the G-P fitting method. The comparison showed reasonable agreement between the simulated and experimental data for all rocks. The results show that sandstone has the highest mean free path as well as exposure buildup factor which signifies that sandstone requires a larger thickness for protection from photons. 相似文献
114.
Mukund G. Kulkarni Saryu I. Davawala Mahadev P. Shinde Attrimuni P. Dhondge Ajit S. Borhade Sanjay W. Chavhan Dnyaneshwar D. Gaikwad 《Tetrahedron letters》2006,47(18):3027-3029
A Wittig olefination-Claisen rearrangement strategy has been applied to achieve one of the shortest and efficient synthesis of (±)-β-cuparenone. 相似文献
115.
A Metalloregulated Four‐State Nanoswitch Controls Two‐Step Sequential Catalysis in an Eleven‐Component System
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M.Sc. Sudhakar Gaikwad M.Sc. Abir Goswami Dr. Soumen De Prof. Dr. Michael Schmittel 《Angewandte Chemie (International ed. in English)》2016,55(35):10512-10517
The nanomechanical switch 1 with its three orthogonal binding motifs—the zinc(II) porphyrin, azaterpyridine, and shielded phenanthroline binding station—is quantitatively and reversibly toggled back and forth between four different switching states by means of addition and removal of appropriate metal‐ion inputs. Two of the four switching stages are able to initiate catalytic transformations (ON1, ON2), while the two others shut down any reaction (OFF1, OFF2). Thus, in a cyclic four‐state switching process the sequential transformation A + B + C → AB + C → ABC can be controlled, which proceeds stepwise along the switching states OFF1→ON1 (click reaction: A + B → AB )→OFF2→ON2 (Michael addition: AB + C → ABC )→OFF1. Two consecutive cycles of the sequential catalysis were realized without loss in activity in a reaction system with eleven different components. 相似文献
116.
V. J. Suryavanshi M. M. Patil S. B. Zanje A. N. Kokare A. P. Gaikwad M. A. Anuse G. N. Mulik 《Russian Journal of Inorganic Chemistry》2017,62(2):257-268
Ruthenium(III) has been efficiently extracted from 0.05 M sodium succinate at pH 9.5 by 2-octylaminopyridine in xylene and stripped with aqueous 10% (w/v) thiourea solution and determined spectrophotometrically. Various parameters viz., pH, weak acid concentration, reagent concentration, stripping agents, contact time, loading capacity, aq.: org. volume ratio, solvent has been thoroughly investigated for quantitative extraction of ruthenium(III). The utility of method was analyzed by separating the ruthenium(III) from binary mixture along with the base metals like Cu(II), Ag(I), Fe(II), Co(II), Bi(III), Zn(II), Ni(II), Se(IV), Te(IV), Al(III) and Hg(II) as well as platinum group metals (PGMs). Ruthenium(III) was also separated from ternary mixtures like Os(VIII), Pd(II); Pd(II), Pt(IV); Pd(II), Au(III); Pd(II), Cu(II); Fe(II), Cu(II); Ni(II), Cu(II); Co(II), Ni(II); Se(IV), Te(IV); Rh(III), Pd(II); Fe(III), Os(VIII). The stoichiometry 1: 2: 1 (metal: succinate: extractant) of the proposed complex was determined by slope analysis method by plotting graph of logD [Ru(III)] versus logC [2-OAP] and logD [Ru(III)] versus logC [succinate]. The interference of various cations and anions has been studied in detail and the statistical evaluations of the experimental results are reported. The method was successfully applied for the analysis of ruthenium in various catalysts, synthetic mixtures corresponding to the composition of alloys and minerals. 相似文献
117.
We investigate the transport of immiscible binary fluid layers, constituted by one conducting (top layer fluid) and another non‐conducting (bottom layer fluid) fluids in a microfluidic channel under the combined influences of an applied pressure gradient and imposed electric field. We solve the transport equation governing the flow dynamics analytically and obtain the closed‐form expressions of the velocity fields. We bring out the alteration in the flow dynamics, mainly attributable to the non‐linear interaction between interfacial slip and the electrical double layer effect over small scales as modulated by the applied pressure gradient. In particular, we show the augmentation in the net volume transport rate through the channel, emerging from an intricate competition among electrical forcing, applied pressure gradient and the viscous resistance as modulated by the interfacial slip. We believe that the results of this study may be of immense consequence for the design of various microfluidic devises, which are often used for the manipulation of two immiscible fluids in different biomedical/biochemical processes. 相似文献
118.
Herein, we report a polyaniline-nickel oxide (PANI-NiO) nanocomposite as an efficient immobilization matrix for development the optical fiber urea biosensor. Optical fiber sensing probe was developed by removing some portion of optical fiber at middle and modified with PANI-NiO matrix. After the modification of cladding removed portion, it was immobilized with enzyme urease via glutaraldehyde as a bi-functional cross-linking agent. The physicochemical and optical properties of the PANI-NiO matrix were explored by X-ray diffraction, scanning electron microscopy, ultraviolet–visible, and Fourier transform infrared spectroscopic techniques. The characteristic features and performance of the developed sensor were evaluated via recording the output power and modal power distribution by means of a charge-coupled device camera. The developed urea biosensor exhibits a selective response towards urea concentrations in the linear range 1 nM–100 mM with a lower detection limit of 1 nM. Sensor recorded as a 40 days stability and response time ~1 min. Thus, the obtained experimental results of the developed sensor promote its applicability with practical prospects in diverse field. 相似文献
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120.
An efficient and eco-friendly synthesis of 1-oxo-hexahydroxanthenes has been expediently accomplished by a reaction of salicylaldehyde with cyclohexane-1,3-dione or dimedone in water as universal solvent at reflux condition without a catalyst. Excellent yields of the products, operational simplicity, simple work-up and catalyst-free synthesis are attractive features of this green protocol. 相似文献