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371.
In the present paper, we discuss three point difference method based on nonpolynomial spline basis for the second order ordinary differential equation. Difference schemes are derived for linear and nonlinear case and are used to solve via two parameter alternating group explicit iterative algorithm. The schemes have a fourth and second order of uniform convergence for the choice of the parameters involved in the method. Computational results are presented comparing the two methods in terms of accuracy and execution times. The results indicate the advantage of using parallel implementation of the new method. 相似文献
372.
Synthesis,Structure, and Optical Studies of Donor–Acceptor‐Type Near‐Infrared (NIR) Aza–Boron‐Dipyrromethene (BODIPY) Dyes 下载免费PDF全文
Naresh Balsukuri Mohsin Y. Lone Dr. Prakash C. Jha Dr. Shigeki Mori Dr. Iti Gupta 《化学:亚洲杂志》2016,11(10):1572-1587
Six donor–acceptor‐type near‐infrared (NIR) aza–boron‐dipyrromethene (BODIPY) dyes and their corresponding aza–dipyrrins were designed and synthesized. The donor moieties at the 1,7‐positions of the aza–BODIPY core were varied from naphthyl to N‐phenylcarbazole to N‐butylcarbazole. The 3,5‐positions were also substituted with phenyl or thienyl groups in the aza–BODIPYs. Photophysical, electrochemical, and computational studies were carried out. The absorption and emission spectra of aza–BODIPYs were significantly redshifted (≈100 nm) relative to the parent tetraphenylaza–BODIPY. Fluorescence studies suggested effective energy transfer (up to 93 %) from donor groups to the aza–BODIPY core in all of the compounds under study. Time‐dependent (TD)‐DFT studies indicated effective electronic interactions between energy donor groups and aza–dipyrrin unit in all the aza–BODIPYs studied. The HOMO–LUMO gap (ΔE) calculated from cyclic voltammetry data was found to be lower for six aza–BODIPYs relative to their corresponding aza–dipyrrins. 相似文献
373.
A low-cost green and reproducible microbes (Lactobacillus sp. and Sachharomyces cerevisae) mediated biosynthesis of TiO2 nanoparticles is reported. The synthesis is performed akin to room temperature in the laboratory ambience. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of TiO2 nanoparticles. Individual nanoparticles as well as a few aggregate having the size of 8–35 nm are found. Concentric Scherrer rings in the selected area electron diffraction pattern indicated that the nanoparticles are having all possible orientations. A possible involved mechanism for the biosynthesis of nano-TiO2 has also been proposed in which pH as well as partial pressure of gaseous hydrogen (rH2) or redox potential of the culture solution seems to play an important role in the process. 相似文献
374.
In the current study, a hot moving steel plate of 6 mm thickness with an initial temperature of 900°C has been considered for jet impingement cooling. The experiment has been designed with the help of Design of Expert software to optimize the process parameters based on the highest cooling rate. The various subsurface transient temperature histories have been measured during the cooling process. The surface heat flux and surface temperature were calculated with the help of a commercial inverse heat transfer solver called INTEMP. The experimental result has been presented in terms of cooling rate and critical heat flux. 相似文献
375.
The thermodynamic properties of an In Sb quantum dot have been investigated in the presence of Rashba spin–orbit interaction and a static magnetic field. The energy spectrum and wave-functions for the system are obtained by solving the Schrodinger wave-equation analytically. These energy levels are employed to calculate the specific heat, entropy,magnetization and susceptibility of the quantum dot system using canonical formalism. It is observed that the system is susceptible to maximum heat absorption at a particular value of magnetic field which depends on the Rashba coupling parameter as well as the temperature. The variation of specific heat shows a Schottky-like anomaly in the low temperature limit and rapidly converges to the value of 2kB with the further increase in temperature. The entropy of the quantum dot is found to be inversely proportional to the magnetic field but has a direct variation with temperature. The substantial effect of Rashba spin–orbit interaction on the magnetic properties of quantum dot is observed at low values of magnetic field and temperature. 相似文献
376.
Silver clad wires of highT
c superconductor Y1Ba2Cu3O7−x
have been fabricated through the powder metallurgy technique. The reacted wires show a midpointT
c of 84K. A critical current density of 26·4 A cm−2 (77K, 0T) is obtained in these wires. The wires, however, turn complete normal only at a current density of 280 A cm−2. The reasons for low critical current density obtained in these wires are discussed. 相似文献
377.
Sergiu P. Albu Andrei Ghicov Steffen Berger Himendra Jha Patrik Schmuki 《Electrochemistry communications》2010,12(10):1352-1355
In the present work we demonstrate the fabrication and use of a new generation of TiO2 nanotube membranes. We show that anodic oxide nanotube growth can be performed through a patterned Ti foil into an underlying Al metal layer. After the selective dissolution of the Al/alumina layer, a very well defined both side open suspended TiO2 nanotube layer can be obtained. Using lithographic patterning of the anodization area allows to achieve very large scale, flexible and well electrically connected nanotubular flow-through membranes with fast electrical switching features over the entire membrane. 相似文献
378.
We have carried out an extensive investigation into the effect of doping on both the A- and B-sites for the multiferroic La(0.5)Bi(0.5)Mn(0.5)Fe(0.5)O(3) in relation to its physical properties. The temperature dependent magnetization and dielectric response are determined for different percentages of Bi- and Fe-substitutions. For La(0.5)Bi(0.5)Mn(0.7)Fe(0.3)O(3), there is a prominent ferromagnetic transition T(C) around 110 K, whereas the other La(0.5)Bi(0.5)Mn(0.3)Fe(0.7)O(3) and La(0.3)Bi(0.7)Mn(0.3)Fe(0.7)O(3) phases fail to exhibit any clear transition. On the other hand, for the Fe-rich phases, the coercive field increases to 2450 Oe compared to 1720 Oe (for the Mn-rich phase). All the compositions exhibit coexistence of ferromagnetic and antiferromagnetic phases at low temperatures. The temperature dependent dielectric constant of the investigated samples varies from 32,000 to 500 at room temperature and the data has been analyzed using the universal dielectric response model. 相似文献
379.
A generalized set of strain variablesq
r
N
, has been defined to develop the expression for a generalized set of second order and third-order elastic moduliC
rs
N
andC
rst
N
for a cubic crystal deformed to orthorhombic structure. The HessainC
rs
N
δqrδqs andC
rst
N
δqrδqsδqt (r=1, 2……6; summation convention) are calculated in the new variables and compared withG-strength andS-strength, for both positive and negative loading environment.
The convexity of the internal energy relative to various choice of strain measure is examined considering up to third degree
terms in the internal energy expression. The computational results forbcc iron is presented according to the new moduli. The stable ranges thus obtained for iron under hydrostatic compressive and
tensile stresses is found to generate the classical stable range, green-stable range and stretch-stable range as the specific
cases. However,bcc iron does not seem to follow any conventional stable ranges under hydrostatic compression, where the present generalized
stable range is found satisfactory. 相似文献
380.
To better understand the association of contaminant uranium with natural organic matter (NOM) and the fate of uranium in ground
water, spectroscopic studies of uranium complexation with catechol were conducted. Catechol provides a model for ubiquitous
functional groups present in NOM. Liquid samples were analyzed using Raman, FTIR, and UV-Vis spectroscopy. Catechol was found
to polymerize in presence of uranyl ions. Polymerization in presence of uranyl was compared to reactions in the presence of
molybdate, another oxyion, and self polymerization of catechol at high pH. The effect of time and dissolved oxygen were also
studied. It was found that oxygen was required for self-polymerization at elevated pH. The potential formation of phenoxy
radicals as well as quinones was monitored. The benzene ring was found to be intact after polymerization. No evidence for
formation of ether bonds was found, suggesting polymerization was due to formation of C-C bonds between catechol ligands.
Uranyl was found to form outer sphere complexes with catechol at initial stages but over time (six months) polycatechol complexes
were formed and precipitated from solution (forming humic-like material) while uranyl ions remained in solution. Our studies
show that uranyl acts as a catalyst in catechol-polymerization. 相似文献