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121.
Let G be a locally compact abelian group with a fixed Haar measure and ω be a weight on G. For 1 < p < ∞, we study uniqueness of uniform and C*-norm properties of the invariant weighted algebra L p (G, ω). 相似文献
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123.
Youssef Ibrahim Moharram El-Hallag Ibrahim Shibl Selim Sameh Mahmoud 《Russian Journal of Electrochemistry》2021,57(6):644-653
Russian Journal of Electrochemistry - Generic products are not identical to their branded equivalents. They are typically off-patent. Therefore, this paper suggests a selective, reliable, and... 相似文献
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125.
This paper studies the fabrication and characterization of 80 nm zinc oxide anti-reflective coating (ARC) on flexible 1.3 μm thin film microcrystalline silicon (μc-Si) solar cell. High resolution X-ray diffraction (HR-XRD) shows a c-axis oriented ZnO (0 0 2) peak (hexagonal crystal structure) at 34.3° with full width at half maximum (FWHM) of 0.3936°. Atomic force microscope (AFM) measures high surface roughness root-mean-square (RMS) of the layer (50.76 nm) which suggests scattering of the incident light at the front surface of the solar cell. UV–vis spectrophotometer illustrates that ZnO ARC has optical transmittance of more than 80% in the visible and infra-red (IR) regions and corresponds to band gap (Eg) of 3.3 eV as derived from Tauc equation. Inclusion of ZnO ARC successfully suppresses surface reflectance from the cell to 2% (at 600 nm) due to refractive index grading between the Si and the ZnO besides quarter-wavelength (λ/4) destructive interference effect. The reduced reflectance and effective scattering effect of the incident light at the front side of the cell are believed to be the reasons why short-circuit current (Isc) and efficiency (η) of the cell improve. 相似文献
126.
Oxygen bridged Homobinuclear Mn(II) compounds with Anthranilic acid: Theoretical calculations,oxidation and catalase activity
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Two new homobinuclear manganese compounds with mixed ligands, [Mn2(μ1,1–2‐NH2C6H4COO)2(phen)4](ClO4)2(CH3OH) ( 1 ), and [Mn2(μ1,3–2‐NH2C6H4COO)2(bipy)4](ClO4)2 ( 2 ) (NH2C6H4COOH = anthranilic acid, bipy = 2,2′‐bipyridine, phen = 1,10‐ phenanthroline) were synthesized and thoroughly characterized by elemental analysis, IR, UV and single crystal X‐ray crystallography. X‐ray structure analysis shows that in the mono‐ and bidentate carboxylate bridged compounds, Mn–Mn distances of 1 and 2 are 3,461 Å, and 4,639 Å, respectively. The energy of the compounds was determined with a DFT (Density Functional Theory) calculation on B3LYP/6‐31G(d,p) optimized geometry by using the B3LYP/6‐31G(d,p) basis set. These compounds acts as biomimetic catalyst and show catalase‐like activity for the hydrogen peroxide dismutation at room temperature in different solvents with remarkable activity (TOF, Turnover frequency = mol of subst./(mol of cat. × time)) up to 12640 h?1 with 1 , and 17910 h?1 with 2 in Tris–HCl buffer). Moreover, the catalytic activity of 1 and 2 has been studied for oxidation of alcohols (cinnamyl alcohol, benzyl alcohol, cyclohexanol, 1‐octanol and 1‐heptanol) and alkenes (cyclohexene, styrene, ethyl benzene, 1‐octene and 1‐hexene) in a homogeneous catalytic system consisting t‐butylhydroperoxide (TBHP) as an oxidant in acetonitrile. Both compounds exhibited very high activity in the oxidation of cyclohexene to cyclohexanone (~80% selectivity, ~99% conversion in 1 h, TOF = 243 h?1 and 226 h?1) and cinnamyl alcohol to cinnamaldehyde (~64% selectivity) as the main product with very high TOF value (9180 h?1 and 13040 h?1 in the first minute of reaction) (~100% conversion in 0.5 h) with TBHP at 70 °C in acetonitrile, for 1 and 2 , respectively. 相似文献
127.
The effects of quantum confined stark effect (QCSE) and quantum well (QW) thickness on the optical properties of violet InGaN laser diodes (LDs) have numerically been investigated. The simulation results indicated that the QCSE greatly effects the optical properties of LDs, where QCSE relates to the QW thickness and it increases when the QW thickness is wider which leads to deteriorating of the optical proprieties of the violet InGaN LD. The polarization in the active region of the InGaN LD has been estimated by the blue shift of the wavelength and it is found that the blue shift of the wavelength depends on the QW thickness. The major simulation result has shown that the best properties of violet InGaN LD can be obtained with smaller QW thickness, where more carriers can be restricted, stayed and overlapped inside the QW which leads to a larger stimulated recombination rate and optical material gain which in turn increase the output power of the LD; while decreasing the threshold current of the LD. 相似文献
128.
A copper metal–organic framework nanoparticles (Cu‐MOF‐NPs) synthesized via simple technique. The prepared Cu‐MOF‐NPs nanoparticles were further characterized using 1H‐NMR, FE‐SEM/EDX and thermal study (DSC/TGA). The FE‐SEM/EDX, thermal analysis, and NMR spectrum data with the other analysis support the nano‐Cu‐MOF structure and the monomeric unit (n[Cu (AIP)2(APY)(H2O)2].4H2O) of Cu‐MOF‐NPs. The photoluminescence (PL) studies of triiodothyronine hormone (T3) based on the prepared Cu‐MOF‐NPs investigated. The results revealed that the Cu‐MOF‐NPs might be used as a biosensor in the determination of triiodothyronine hormone (T3) in biological fluids through a significant quenching of the photoluminescence intensity of Cu‐MOF‐NPs at excitation wavelength 492 nm. The calibration plot achieved over the concentration range 0.0–200.0 ng/dL T3 hormone with a correlation coefficient 0.996 and limit of detection (LOD) and quantification (LOQ) 0.198 and 0.60 ng/dL, respectively. The PL spectra are indicating that Cu‐MOF‐NPs has highly selective sensing properties for T3 hormone without interfering with other human many hormones types. This approach considered a promising analytical tool for early diagnosis of the cases of thyroid disease. The mechanism of quenching between the Cu‐MOF‐NPs, and T3 hormone studied. The mechanism was a dynamic type and obtained due to the energy transfer mechanism. 相似文献
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130.
I. M. Abd-ellah E. H. M. Ibrahim A. N. El-khazandar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-4):239-247
Abstract Interaction of chlorocyclodiphosphazanes (I) with some bifunctional reagents (such as phenylurea, diphenylurea, thiourea and its phenyl derivatives) in acetonitrile furnished geminal and nongeminal aminocyclodiphosphazanes of type (II–V). The structures of the isolated products were proposed on the basis of microanalytical data, infrared, ultraviolet, 1H n.m.r., and mass spectra. The mechanism of the nucleophilic substitution is also discussed. 相似文献