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41.
42.
An evanescent-field-coupled waveguide-mode sensor of the Kretschmann configuration with a silica waveguide having nanoscale holes is an ideal tool for detection of bimolecular reactions. In the present research, an optimized surface of the sensor with cylindrical nanoscale holes was modified with sodium (1-{[6-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)hexanoyl]oxy}-2,5-dioxopyrrolidine-3-sulfonate) (Sulfo-EMCS) to facilitate the attachment of biomolecules; the resulting surface could be cleaned for reuse simply by changing the pH of the buffering solution. The modification is expected to be useful for wide range of molecular detection. 相似文献
43.
Tambe Adinath Sadaphal Gayatri Dhawale Ravindra Shirole Gopinath 《Research on Chemical Intermediates》2022,48(3):1273-1286
Research on Chemical Intermediates - In the present investigation, we have developed an efficient and eco-friendly protocol for the synthesis of pyrazole anchored 1,4-dihydropyridine analogs using... 相似文献
44.
In this paper,we present a stable,reliable and robust method for reconstructing a three dimensional density function from a set of two dimensional electric tomo... 相似文献
45.
T. Suresh S. Vetrivel S. Gopinath R.U. Mullai 《Chinese Journal of Physics (Taipei)》2018,56(6):2773-2781
Single crystal of l-Asparagine Indium chloride (LAIn), a new semi-organic crystal was grown by slow evaporation method with deionized water as solvent at ambient condition. The crystal structure of LAIn has been determined by single crystal X-ray diffraction and the result shows that the crystal belongs to the orthorhombic system with P212121 space group. The crystalline nature of grown crystal was analyzed by powder X-ray diffraction analysis. Optical parameters, such as absorbance, transmittance and optical band gap energy were analyzed using UV–Vis NIR transmittance data at the range of 190–800?nm. The ultraviolet (UV) emission nature of the sample was established from the sharp emission peaks in photoluminescence (PL) spectrum. The photo conductivity test exhibits that the grown crystal has positive photo conductive nature. The induced surface laser damage threshold (LDT) for the grown crystal was measured using Nd:YAG laser. The nonlinear optical efficiency of the LAIn crystal was studied using modified Kurtz-Perry powder technique. The hardness, Meyer index, yield strength and elastic stiffness constant were calculated for the grown crystal using Vickers microhardness tester. The variation of dielectric constant and dielectric loss of the grown crystals as a function of frequency has been investigated at different temperatures. The melting point and thermal stability of the LAIn single crystal have been studied by thermo gravimetric analysis and differential thermal analysis (TG/DTA). 相似文献
46.
Calycanine, the degradation product of the alkaloid calycanthine, has been synthesized. 相似文献
47.
[reaction: see text] Aldehydes, in the presence of methanol, undergo oxidative transformation to the corresponding esters upon treatment with catalytic amounts of vanadium pentoxide in combination with oxidant hydrogen peroxide. Mild reaction conditions, shorter reaction times, high efficiencies, cost-effectiveness, and facile isolation of the desired products make the present methodology a practical alternative. 相似文献
48.
A T-space U of degree k is a (k + 1)-dimensional vector space over
(the real line) of real-valued functions defined on a linearly ordered set, satisfying the condition: for every nonzero u ε U, Z(u), the number of distinct zeros of u and -(u), the number of alternations in sign of u(t) with increasing t, each do not exceed k. It is demonstrated that given a T-space U of degree k > 0 on an arbitrary linearly ordered set T, there is a subset T′ of the real line and a nonsingular linear map L:U→ C(T′), the set of continuous functions on T′, such that the following hold: L(U) is a T-space of degree k; for u ε U, Z(u) = Z(L(u)), S−(u) = S−(L(u); and for some order-preserving bijection Θ:T → T′, u(t) = O if and only if L(u)(Θ(t) = 0. It is also shown that a T-space on a subset T
can be extended to a T-space on the closure of T in ]inf T, sup T], provided that there are no “interval gaps” in T. Examples show that, in general, a T-space cannot be extended across an “interval gap” in its domain, and cannot be extended to both the infimum and supremum of its domain. Conditions for a T-space to be Markov, and to admit an adjoined function are derived. 相似文献
49.
Dr. Tata Gopinath Dr. Veliparambil S. Manu Dr. Daniel K. Weber Prof. Gianluigi Veglia 《Chemphyschem》2022,23(13):e202200127
Solid-state NMR (ssNMR) spectroscopy has emerged as the method of choice to analyze the structural dynamics of fibrillar, membrane-bound, and crystalline proteins that are recalcitrant to other structural techniques. Recently, 1H detection under fast magic angle spinning and multiple acquisition ssNMR techniques have propelled the structural analysis of complex biomacromolecules. However, data acquisition and resonance-specific assignments remain a bottleneck for this technique. Here, we present a comprehensive multi-acquisition experiment (PHRONESIS) that simultaneously generates up to ten 3D 1H-detected ssNMR spectra. PHRONESIS utilizes broadband transfer and selective pulses to drive multiple independent polarization pathways. High selectivity excitation and de-excitation of specific resonances were achieved by high-fidelity selective pulses that were designed using a combination of an evolutionary algorithm and artificial intelligence. We demonstrated the power of this approach with microcrystalline U-13C,15N GB1 protein, reaching 100 % of the resonance assignments using one data set of ten 3D experiments. The strategy outlined in this work opens up new avenues for implementing novel 1H-detected multi-acquisition ssNMR experiments to speed up and expand the application to larger biomolecular systems. 相似文献
50.
KS Thushara ES Gnanakumar R Mathew TG Ajithkumar PR Rajamohanan S Bhaduri CS Gopinath 《Dalton transactions (Cambridge, England : 2003)》2012,41(37):11311-11318
A new molecular adduct of MgCl(2) with isobutanol, namely MgCl(2)·4((CH(3))(2)CHCH(2)OH) (MgiBOH), has been prepared as a precursor to the supporting material for an olefin polymerization catalyst. The MgiBOH adduct and final titanated Ziegler-Natta catalysts have been thoroughly characterized by powder XRD, thermal analysis, Raman spectroscopy and solid-state NMR for structural and spectroscopy aspects. A peak observed at 712 cm(-1) in the Raman spectra of MgiBOH indicates the characteristic Mg-O(6) breathing mode and the formation of the adduct. The diffraction feature at 2θ = 7.8° (d = 11.223 ?) in the XRD confirms the adduct formation and the layered structure. The aim of the present article is to study how the insertion of a bulky isobutanol moiety affects the structural and electronic properties of the MgCl(2)·isobutanol molecular adduct. Indeed, the focus of the present study is to explore how the presence of isobutanol, in the initial molecular adduct, influences the final Z-N catalyst properties and its activity. 相似文献