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141.
Saleh MI Kusrini E Mohd Sarjidan MA Abd Majid WH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(1):52-58
A mononuclear of [Eu(NO3)(Pic)(H2O)2(EO3)](Pic)·(0.73)H2O complex, where EO3=trietraethylene glycol and Pic=picrate anion, shows a red emission when used as an active layer in a single layer of ITO/EO3-Eu-Pic/Al configuration. The crystal structure of the complex consists of [Eu(NO3)(Pic)(H2O)2(EO3)]+ cation and [Pic]- anion. The Eu(III) ion is coordinated to the 10 oxygen atoms from one EO3 ligand, one Pic anion, one nitrate anion, and two water molecules. The complex is crystallized in triclinic with space group P-1. The hybrids in thin films I and II were prepared in the respective order solution concentrations of 15 and 20 mg/mL the emissive center. Comparing the photoluminescence (PL) and electroluminescence (EL) spectra, we can find that all emissions come from the characteristic transitions of the Eu(III) ion. The EL spectra of both thin films showed the occurrence of the most intense red-light emission around at 612 nm. Comparison of organic light-emitting device (OLED) current intensity characteristics as a function of voltage (I-V) show that the thin film I is better than those found for the thin film II. The thickness of the emitting layer is an important factor to control the current-voltage curve. The sharp and intense emission of the complex at low voltage indicates that the complex is a suitable and promising candidate for red-emitting materials. 相似文献
142.
《Communications in Nonlinear Science & Numerical Simulation》2011,16(3):1263-1273
We propose a novel split-step quadratic B-spline finite element method for solving the initial-boundary value problem of the coupled Schrödinger–KdV equations. A full-discrete finite element scheme is constructed. The conserved properties of the full-discrete scheme are proved. Detailed numerical results show the efficiency of our scheme. 相似文献
143.
144.
Md. Azizul Baten 《Journal of Mathematical Sciences》2011,177(3):329-344
This paper studies the production inventory problem of minimizing the expected discounted present value of production cost
control in a manufacturing system with degenerate stochastic demand. We establish the existence of a unique solution of the
Hamilton-Jacobi-Bellman (HJB) equation associated with this problem. The optimal control is given by a solution to the corresponding
HJB equation. 相似文献
145.
Gel polymer electrolytes were prepared using agar polymer host, NH4I, and I2 salts. The sample of agar paste with 1.0 M of NH4I and 0.2 μM of I2 exhibits the highest conductivity and lowest viscosity values at room temperature of (2.64?±?0.19)?×?10?3?S?cm?1 and 1.17?±?0.29 Pa?s, respectively. All of the gel polymer electrolytes display Arrhenian behavior, and the optimum agar paste gave the lowest activation energy of 0.25 eV. It also had a good physical appearance compared with the other samples. This gel polymer electrolyte had a good potential and was applicable to a role as electrolyte in ITO-ZnO (N719 dye)/agar paste?+?1.0 M NH4I?+?0.2 μM I2/Au-Pd-ITO dye-sensitized solar cell. 相似文献
146.
For 0 < α ≤ 1, analytic functions f(z) = z + a2z2 + a3z3 + … in the unit disk U are strongly starlike of order α if ¦arg {zf′ (z)/f(z)}¦ < πα / 2, z ∈ U. We find sharp estimates on the fourth and fifth coefficients of functions in this class. 相似文献
147.
《Solid State Communications》2006,137(1-2):63-66
High Al-content AlxGa1−xN films were deposited on (001) and (111) Si substrates at 1000 °C using high temperature AlN buffer layers. Experimental results show that AlxGa1−xN films grown on (111) Si substrates exhibit better crystalline quality than that in the films deposited on (001) Si substrates. Cracks were found in the high Al-content AlxGa1−xN/(111) Si samples but they were not observed in the AlxGa1−xN films grown on (001) Si substrates having the same film thicknesses and Al compositions. Based upon the results of X-ray diffraction (XRD) and transmission electron microscopy (TEM), it appears that mono-crystalline AlxGa1−xN films were achieved on (111) Si substrates while columnar structure was observed in the AlxGa1−xN/(001) Si samples. According to the depth profiles of AlxGa1−xN/Si samples using secondary ion mass spectroscopic (SIMS) analyses, enhanced Al inter-diffusion in the AlxGa1−xN/(001) Si samples was identified. Room temperature (RT) photoluminescence (PL) measurements of the AlxGa1−xN (x≦0.10)/(111) Si samples exhibit strong near band edge luminescence. The PL emission linewidth was found to decrease with the decrement of Al-content. 相似文献
148.
Farook Ahmad Ahmad Pauzi Mohd Yusof Martina Bainbridge Sulaiman Ab Ghani 《Electroanalysis》2007,19(5):541-548
Hydrogen peroxide (H2O2) was the main types of many peroxides produced in living mammalian cells that consumed oxygen. In the brain, the main source of H2O2 was the superoxide dismutase (SOD)‐catalyzed reaction in mitochondria. However, the level of H2O2 would be elevated through administration of control drugs and alcohol by dopamine metabolism of monoamine oxidase. In this study, a H2O2 microsensor was used to investigate the level of H2O2 in the brain striatum after administration of methamphetamine (MAP), morphine (MrP) or ethanol (Eth). The placement of microsensor in the brain was done at coordinates A/P 1.1 from bregma, M/L+2.6 and D/V‐1.5. A working potential of +0.05 V vs. Ag/AgCl was applied. The H2O2 concentration was measured direct from the current generated by its catalytic reaction at the electro active surface of the electrode. A significant increase of H2O2 level was observed after 7 successive injections of the controlled drugs or alcohol. The initial measurement of H2O2 is essential as excess dosage of H2O2 during treatment will contribute to the formation of neurotoxin oxygenated radicals. The H2O2 was the precursor of O2? and OH radicals. Thus, this study provided a mean to monitor H2O2 level in the brain. 相似文献
149.
《European Journal of Operational Research》2006,175(2):1311-1320
In this paper, we conduct simulation experiments to evaluate the performance of two alternative uses of the super-efficiency procedure in Data Envelopment Analysis (DEA). The first is for outlier identification and the second is for ranking efficient units. We find that the ranking procedure does not perform satisfactorily. In fact, the correlations between the true efficiency and the estimated super-efficiency are negative for the subset of efficient observations, and the conventional DEA model performs as well as the super-efficiency DEA model when all observations are considered. However, when data are contaminated with outliers, the use of the super-efficiency model to identify and remove outliers results in more accurate efficiency estimates than those obtained from the conventional DEA estimation model. 相似文献
150.
Surendran Ramasamy Abdul Rahman Mohamed Subhash Bhatia 《Reaction Kinetics and Catalysis Letters》2002,75(2):353-358
Oxidative coupling of methane for the production of ethylene was studied over Li-Ni/MgO catalyst in a fixed bed reactor. The influences of important reaction parameters such as temperature (T), methane/oxygen ratio (CH4/O2) in feed and space velocity of reactants (V/mcat) were studied over the conversion of methane, yields of ethylene and ethane and selectivity of ethylene formation. The reaction conditions were varied as 650 < T < 850oC, 0.83 x 10-6 < V/mcat < 2.92 x 10-6 m3/g s and 1 < CH4/O2 ratio < 8. 相似文献