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41.
A nickel oxide film with a thickness of 445 nm was deposited from nickel acetate precursor using the sol–gel dip coating method.
The NiO films exhibit optical transmission of 84% at 550 nm and direct energy gap (E
gd) value is 3.64 eV. The FTIR spectrum of the films confirms the formation of Ni–O bond. XRD spectrum reveals the formation
of nano crystallites along (111) and (200) planes with a particle size of 17 nm. The electrochromic properties have been studied
using cyclic voltammetric (CV) technique. The optical transmission of a glass/FTO/NiO/ZrO2/FTO/glass EC device is reported. 相似文献
42.
A simple technique is given for measuring stresses in reflecting thin films, using real-time holography. The technique gives clear real fringes with good visibility which can be easily monitored and photographed. No substrate profile measurement is needed. Thermal stress of 0.49 × 109 dynes cm-2 is observed for a 200.0 nm thick Ag film in the temperature range of 30 to 55°C. This is in good agreement with reported values. 相似文献
43.
High‐resolution slice selection NMR for the measurement of CO2 diffusion under non‐equilibrium conditions
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We present a simple and an efficient approach using spatially selective NMR to investigate solvation and diffusion of CO2 in ionic liquids. The techniques demonstrated here are shown as novel and effective means of studying solvated gas dynamics under non‐equilibrium conditions without the need for conventional high power gradients. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
44.
Chau N. Tang Hunaid B. Nulwala Krishnan Damodaran Palwinder Kaur David R. Luebke 《Journal of polymer science. Part A, Polymer chemistry》2011,49(9):2024-2032
CO2‐based, crosslinked poly(hydroxyl urethane)s (PHUs) are accessed via a set of efficient reactions based on the addition chemistry of thiol‐ene and amines‐cyclic carbonates. This strategy to utilize 5‐membered cyclic carbonates produced from CO2 is robust, facile, modular, and atomically efficient in nature. The thiol‐ene reaction was utilized to access bis(cyclic carbonate), tris(cyclic carbonate), and tetrakis(cyclic carbonate) in quantitative yield from 4‐vinyl‐1,3‐dioxolan‐2‐one and thiols. Multi‐functional cyclic carbonates were simply mixed with diethylenetriamine and/or 1,6‐diaminohexane to generate crosslinked PHUs from 25 to 80 °C. These materials are easy to scale‐up and are potential candidates in many applications such as coatings, binders, and resins. The resulting polymers have glass transition temperatures between ?1 and 16 °C and thermal decomposition temperatures from 190 to 230 °C. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
45.
Synthesis of 13- and 16-membered macrocyclic enone with alkyl ether and triazole as a linker was achieved using intramolecular aldol condensation. The newly synthesized macrocyclic enone was successfully utilized as a dipolarophile in 1,3-dipolar cycloaddition (1,3-DC). The dipole generated from isatin/acenaphthenequinone with various secondary amino acids (sarcosine, l-proline, and thiazolidine-4-carboxylic acid) were reacted with macrocyclic enone to give a new class of spiropyrrolidine-grafted macrocycles in good yield (>85%). The structures were assigned by 2D NMR spectra and the regio- and stereochemical outcome of the cycloadducts were established by a single crystal X-ray analysis. 相似文献
46.
The sol-gel dip-coating method is used for the preparation of MoO3 thin films. The 6 layered MoO3 films were prepared and annealed at various temperatures in the range of 200-350 °C. The band gap value for MoO3 films were calculated from optical absorption measurements and it is in the range of 3.55-3.73 eV. XRD spectrum reveals (0 2 0) is the major diffraction plane for the films prepared above 250 °C, which reveals the formation of MoO3 in α-orthorhombic phase. The films prepared at 200 °C and 250 °C exhibits amorphous nature. The FTIR spectrum confirms the presence of Mo-O-Mo and MoO bonds. Nanorods were observed in the SEM images in the case of MoO3 films prepared above 250 °C. The films prepared at 250 °C exhibit maximum anodic diffusion coefficient of 9.61 × 10−11 cm2/s. The same film exhibits the change in optical transmission of 58.4% at 630 nm with the optical density of 0.80. 相似文献
47.
B. V. Reddy L. K. Reddy A. S. Reddy M. L. P. Reddy T. R. Ramamohan A. D. Damodaran 《Journal of Radioanalytical and Nuclear Chemistry》1993,172(1):167-179
The extraction of Er(III) and Lu(III) from thiocyanate media with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHEHPA) and also with mixtures of EHEHPA and thenoltrifluoroacetone (HTTA) or tri-n-octylphosphine oxide (TOPO) or bis 2-ethylhexyl sulfoxide (B2EHSO) in benzene has been studied systematically. Synergistic effects have been observed with mixtures of EHEHPA+HTTA or TOPO. On the other hand, antagonistic effects have been observed with mixtures of EHEHPA+B2EHSO. These extraction data have been analyzed theoretically with the aid of a computer by taking into account complexation of the metal in the aqueous phase by SCN– and plausible complexation in the organic phase. The extraction constants of the various product species have been deduced by non-linear regression analysis. The stability constants for the thiocyanate complexes of the metal ions have also been determined. 相似文献
48.
Time‐dependent incompressible Navier–Stokes equations are formulated in generalized non‐inertial co‐ordinate system and numerically solved by using a modified second‐order Godunov‐projection method on a system of overlapped body‐fitted structured grids. The projection method uses a second‐order fractional step scheme in which the momentum equation is solved to obtain the intermediate velocity field which is then projected on to the space of divergence‐free vector fields. The second‐order Godunov method is applied for numerically approximating the non‐linear convection terms in order to provide a robust discretization for simulating flows at high Reynolds number. In order to obtain the pressure field, the pressure Poisson equation is solved. Overlapping grids are used to discretize the flow domain so that the moving‐boundary problem can be solved economically. Numerical results are then presented to demonstrate the performance of this projection method for a variety of unsteady two‐ and three‐dimensional flow problems formulated in the non‐inertial co‐ordinate systems. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
49.
The ultrasonic longitudinal sound wave attenuation coefficient and nuclear spin relaxation rate have been calculated for an anisotropic superconductor containing paramagnetic impurities with local states within the gap. The local states within the gap is shown to be anisotropic. 相似文献
50.
Contents of boron (ppm), magnesia (%) and silica (%) of thirty samples of basic and ultrabasic rocks and 8 samples of serpentinites from Nuggihalli schist belt have been determined by spectrochemical, E.D.T.A. and colorimetric methods respectively. From the analytical data it is found that boron in serpentinites and ultrabasic rocks has higher clarks. The increase of boron in serpentinites and ultrabasic rocks is suggestive of allometamorphism. From the geochemical and statistical investigations it appears that there exists a correlation between the content of boron and magnesia in the basic and ultrabasic rocks and in serpentinites. Boron content in brown serpentinite is less than in platy serpentinite. 相似文献