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91.
Venkatraman Senthil Kumar Choudhary Rajan Genasan Krishnamurithy Murali Malliga Raman Raghavendran Hanumantha Rao Balaji Kamarul Tunku Suresh Anushree Abraham Jayanthi Venkateswaran Seshasailam Livingston Abel Swamiappan Sasikumar 《Journal of Sol-Gel Science and Technology》2021,100(3):506-516
Journal of Sol-Gel Science and Technology - Biocompatibility and bacterial infections are the primary concerns associated with the current bone graft substitutes. The application of... 相似文献
92.
Heiko Packeiser Chanyuen Lim Balaji Balagurunathan Jinchuan Wu Hua Zhao 《Applied biochemistry and biotechnology》2013,169(2):695-700
An extremely simple and effective colony PCR procedure is established for both gram-negative and gram-positive bacteria, yeasts, and microalgae. Among the four lysis buffers examined, Y-PER is observed to be more effective than Tris/EDTA, 0.2 % SDS, and 10 mM EDTA in the extraction of PCR-quality genomic DNA from those microorganisms. Vortexing or pipetting agitation of the cells in Y-PER for 5–10 s was sufficient to release genomic DNA for all the test bacteria and yeasts, and most microalgae. Additional incubation at 98 °C for 5 min for further cell disruption was essential only for Chlorella vulgaris due to its notoriously rigid cell wall. 相似文献
93.
94.
NiZnS electrode has been investigated for use in oxygen evolution reaction in alkaline media. Nickel mesh electrode was coated with the ternary composition of NiZnS by four methods, viz., direct current electrodeposition, pulse electrodeposition, sonoassisted direct current electrodeposition and sonoassisted pulse electrodeposition. The oxygen evolution studies carried out using these electrodes resulted in higher current density for the electrode prepared by sonoassisted pulse electrodeposition compared to those prepared by other methods. Effect of plating current density, pulse duty cycle and temperature on the electrochemical parameters of the alloy coating has been studied. Surface morphologies of the various coating were studied using scanning electron microscopy. Long-term stability of the electrodes prepared was studied in alkaline medium. Exchange current density (j o) was found to increase with the increase in temperature and was the highest for sonoassisted pulse electrodeposited electrode. 相似文献
95.
This paper reports the use of the technique of combining asymptotics with computational fluid dynamics (CFD), known as asymptotic
computational fluid dynamics (ACFD), to handle the problem of combined laminar mixed convection and surface radiation from
a two dimensional, differentially heated lid driven cavity. The fluid under consideration is air, which is radiatively transparent,
and all the walls are assumed to be gray and diffuse and having the same hemispherical, total emissivity (ɛ). The computations
have been performed on FLUENT 6.2. The full radiation problem (i.e. all the walls are radiatively black corresponding to ɛ
= 1) is first taken up and the method of “perturbing and blending” is used wherein, first, limiting solutions of natural and
forced convection are perturbed, to obtain correlations for the weighted average convective Nusselt numbers for the full radiation case. These correlations are then blended suitably in order to obtain a composite
correlation for the weighted average convective Nusselt number that is valid for the entire mixed convection range, i.e., 0 ≤ Ri ≤ ∞. This correlation is then expanded in terms of ɛ to obtain an expression for the average convective Nusselt number that is valid for any ɛ in the range 0 ≤ ɛ ≤ 1. In so far as radiation heat transfer is concerned, using asymptotic
arguments, a new weighted average radiation Nusselt number is defined such that this quantity can be expanded just in terms of ɛ. Hence, by the use of ACFD, the number
of solutions required to obtain reasonably accurate correlations for both the convective and radiative heat transfer rates
and hence the total heat transfer rate (Nu
total = Nu
C + Nu
R), is substantially reduced. More importantly, the correlations for convection and radiation are asymptotically correct at
their ends. The effect of secondary variables like aspect ratio and the case of unequal wall emissivities can also be included
without significant additional effort. 相似文献
96.
A numerical investigation is carried out to study fluid flow and heat transfer characteristics of conjugate mixed convection from a two dimensional horizontal channel with four protruding heat sources mounted on one of the finite thick channel walls. The flow is assumed as laminar, hydrodynamically and thermally developing. Water and FC70 are the fluids under consideration. The geometric parameters such as spacing between the channel walls (S), size of protruding heat sources (Lh×th), thickness of substrate (t) and spacing between heat sources (b) are fixed. Results are presented to show the effect of parameters such as ReS, GrS*, Pr, kp/kf and ks/kf on fluid flow and heat transfer characteristics. Using the method of asymptotic expansions, correlations are also presented for the maximum temperature of heat source. 相似文献
97.
This paper presents the results of a comprehensive numerical study to analyze conjugate, turbulent mixed convection heat transfer
from a vertical channel with four heat sources, uniformly flush-mounted to one of the channel walls. The results are presented
to study the effect of various parameters like thermal conductivity of wall material (k
s), thermal conductivity of flush-mounted discrete heat source (k
c), Reynolds number of fluid flow (Re
s), modified Richardson number (Ri
+) and aspect ratio (AR) of the channel. The standard k-ε turbulence model, modified by including buoyancy effects with physical boundary conditions, i.e. without wall functions,
has been used for the analysis. Semi-staggered, non-uniform grids are used to discretise the two dimensional governing equations,
using finite volume method. A correlation, encompassing a wide range of parameters, is developed for the non-dimensional maximum
temperature (T
*) using the asymptotic computational fluid dynamics (ACFD) technique. 相似文献
98.
G. L. Balaji K. Rajesh Shabana Kouser Ali V. Vijayakumar 《Research on Chemical Intermediates》2013,39(4):1807-1815
Ultrasound-promoted reaction of substituted 2,4-dichloroquinolines (1) with ethyl 4-(3-hydroxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (2) in the presence of K2CO3 as mild base at moderate temperatures leads to 2-chloroquinolin-4-pyrimidine carboxylate derivatives (3) with high regioselectivity. All the compounds synthesized were characterized by use of spectral data and screened for their antibacterial activity against two Gram-positive (Staphylococcus aureus, Bacillus cereus) and two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. Activity was moderate. 相似文献
99.
Yahia Djaoued Subramanian Balaji Normand Beaudoin 《Journal of Sol-Gel Science and Technology》2013,68(3):516-525
Mesoporous WO3–TiO2 composite films were prepared by a sol gel based two stage dip coating method and subsequent annealing at 450, 500 and 600 °C. An organically modified silicate based templating strategy was adopted in order to obtain a mesoporous structure. The composite films were prepared on ITO coated glass substrates. The porosity, morphology, and microstructures of the resultant products were characterized by scanning electron microscopy, N2 adsorption–desorption measurements, μ-Raman spectroscopy and X-ray diffraction. Calcination of the films at 450, and 500 °C resulted in mixed hexagonal (h) plus monoclinic phases, and pure monoclinic (m) phase of WO3, respectively. The degree of crystallization of TiO2 present in these composite films was not evident. The composite films annealed at 600 °C, however, consist of orthorhombic (o) WO3 and anatase TiO2. It was found that the o-WO3 phase was stabilized by nanocrystalline anatase TiO2. The thus obtained mesoporous WO3–TiO2 composite films were dye sensitized and applied for the construction of photochromic devices. The device constructed using dye sensitized WO3–TiO2 composite layer heat treated at 600 °C showed an optical modulation of 51 % in the NIR region, whereas the devices based on the composite layers heat treated at 450, and 500 °C showed only a moderate optical modulation of 24.9, and 38 %, respectively. This remarkable difference in the transmittance response is attributed to nanocrystalline anatase TiO2 embedded in the orthorhombic WO3 matrix of the WO3–TiO2 composite layer annealed at 600 °C. 相似文献
100.
Abstract Copolymers of 3-methoxy-4-acryloyloxybenzal phenylimine and methyl methacrylate with different feed ratios are synthesized in ethyl methyl ketone using benzoyl peroxide as a free radical initiator at 70 ± 1°CC. The polymers were characterized by IR and 1H-NMR spectroscopic techniques. Copolymer compositions were determined by lH-NMR analysis of the polymers. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman-Rose and Kelen-Tüdös. The molecular weights Mn and Mw of the polymers and the poly-dispersity index were determined by gel permeation chroma-tography. The intrinsic viscosities and the thermal properties of the homo-and copolymers are also discussed. 相似文献