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81.
S. Samundeeswari Lokesh A. Shastri Bahubali M. Chougala Megharaja Holiyachi Manohar V. Kulkarni 《Tetrahedron letters》2017,58(20):1996-1998
Oxime ethers obtained from benzil monooxime and 4-bromomethy coumarins have undergone an unusual transformation into coumarin-4-carboxamides. Structures of the products have been supported by X-ray studies and robustness of the reaction has been investigated for a variety of substituent. 相似文献
82.
G. Pathak R. Katiyar K. Agrahari A. Srivastava R. Dabrowski K. Garbat R. Manohar 《Opto-Electronics Review》2018,26(1):11-18
In the present work TiO2 nanoparticles (NPs) have been dispersed into three different nematic liquid crystals (2020, 1823A and 1550C) in different concentration. The value of the birefringence (Δn) has been calculated by the transmitted intensity method at a 632.8 nm wavelength. NLC 2020 used in the present study is a high birefringent material (Δn = 0.44), NLC 1550C is a low birefringent material (Δn = 0.067) and NLC 1823A is a mid birefringent material (Δn = 0.14). An increased value of birefringence has been found after dispersion of TiO2 NPs in all three NLCs but this increment depends upon the concentration of the dopant material, temperature range and chemical character of the mixtures. It is suggested that this LC materials can be applicable in making of phase shifters, compensators and many more photonic devices. 相似文献
83.
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85.
Kumar Sundaravel Vivek Rani Gandhi Uma Divyalakshmi Manohar Bhuvanesh Nattamai Muthusubramanian Shanmugam Perumal Subbu 《Molecular diversity》2019,23(3):669-680
Molecular Diversity - Expedient synthesis of benzosuberone-tethered spirooxindoles was accomplished by a three-component 1,3-dipolar cycloaddition reaction between azomethine ylide (generated in... 相似文献
86.
Murli Manohar Verma Shankar Dayal Pathak 《International Journal of Theoretical Physics》2012,51(8):2370-2379
We investigate the tachyonic cosmological potential V(?) in two different cases of the quasi-exponential expansion of universe and discuss various forms of interaction between the two components—matter and the cosmological constant—of the tachyonic scalar field, which lead to the viable solutions of their respective energy densities. The distinction among the interaction forms is shown to appear in the O m (x) diagnostic. Further, the role of the high- and low-redshift observations of the Hubble parameter is discussed to determine the proportionality constants and hence the correct form of matter–cosmological constant interaction. 相似文献
87.
M. L. Shah R. C. Das P. K. Mandal D. R. Rathod Vas Dev K. G. Manohar B. M. Suri 《Pramana》2010,75(6):1141-1144
We report the measurement of photoexcitation cross-sections of three first-step uranium transitions (0 → 16900.38 cm −1, 0 → 17361.89 cm −1 and 620 → 17361.89 cm −1) using saturation method. These measurements were performed on a resonance ionization mass spectrometry (RIMS) set-up consisting
of Nd:YAG-pumped dye lasers, a reflectron time-of-flight mass spectrometer and high-temperature atomic vapour source. The
uranium vapours were excited and photoionized by two-colour, three-photon photoionization scheme using Nd:YAG-pumped dye laser
system. The resultant photoion signal was monitored as a function of dye laser fluence used for first step excitation to measure
the excitation cross-section values. A new approach was adopted to overcome the large uncertainties associated with such measurements.
With this approach the cross-section of transitions whose value is already reported in the literature was measured as a bench
mark. By normalizing the measured value to the reported value, a scaling factor was derived. This scaling factor was used
to scale up the cross-section values of other transitions measured by this method. 相似文献
88.
Madhura R. Joglekar Evelyn Sander James A. Yorke 《Journal of Fixed Point Theory and Applications》2010,8(1):151-176
Period-doubling cascades are among the most prominent features of many smooth one-parameter families of maps, \({F : \mathbb{R}\times\mathfrak{M} \rightarrow \mathfrak{M},}\) where \({\mathfrak{M}}\) is a locally compact manifold without boundary, typically \({\mathbb{R}^N}\). In particular, we investigate F(μ, ·) for \({\mu \in J = [\mu_{1}, \mu_{2}]}\), when F(μ 1, ·) has only finitely many periodic orbits while F(μ 2, ·) has exponential growth of the number of periodic orbits as a function of the period. For generic F, under additional hypotheses, we use a fixed point index argument to show that there are infinitely many “regular” periodic orbits at μ 2. Furthermore, all but finitely many of these regular orbits at μ 2 are tethered to their own period-doubling cascade. Specifically, each orbit ρ at μ 2 lies in a connected component C(ρ) of regular orbits in \({J \times \mathfrak{M}}\); different regular orbits typically are contained in different components, and each component contains a period-doubling cascade. These components are one-manifolds of orbits, meaning that we can reasonably say that an orbit ρ is “tethered” or “tied” to a unique cascade. When F(μ 2) has horseshoe dynamics, we show how to count the number of regular orbits of each period, and hence the number of cascades in \({J \times \mathfrak{M}}\).As corollaries of our main results, we give several examples, we prove that the map in each example has infinitely many cascades, and we count the cascades. 相似文献
89.
The molybdenum (Mo) and ferric (Fe) doped potassium titanyl phosphate (KTP) crystals were grown by high temperature solution growth (HTSG) technique. The concentration of Mo and Fe in grown crystals was measured by EDX analysis. The SHG efficiencies of the Mo and Fe doped KTP crystals were measured and it was found to be 1.77 and 1.38 times respectively higher than that of pure KTP crystal. The frequency dependence of dielectric constant, loss and ac conductivity was studied at room temperature. The phase matching measurements were made using a Q-switched Nd:YAG laser operating at 1064 nm and the measured phase matching angles are 44.2° and 87.88° for Mo and Fe doped KTP crystals respectively. 相似文献
90.