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121.
Hanaa A. El-Boraey Randa M. Abdel-Rahman Ensaf M. Atia Khalid H. Hilmy 《Central European Journal of Chemistry》2010,8(4):820-833
Two novel Schiff base ligands of 2-amino-3-cyano-1,5-diphenylpyrrole and salicylaldehyde (HL1) or 2- hydroxy1-naphthylaldehyde (HL2) and their copper(II) complexes have been synthesized and characterized by elemental analyses, spectral (UV-Vis, IR, EPR,
Mass (for ligands)), thermal (DTA-TGA) methods, magnetic and conductance measurements. IR results demonstrate the bidentate
binding of the Schiff base ligands involving azomethine nitrogen, phenolic or naphtholic oxygen and suggest the presence of
HL2 and complexes (1, 2, 4 and 8) in enolimine-ketonamine tautomeric forms in the solid state. The EPR spectral data of complexes
(2, 5, 6) show that the metal — ligand bonds have considerable covalent character. The thermal studies show that complexes
(1, 2, 4 and 8) that are present in enolimine-ketonamine tautomeric forms exhibit lower thermal stability. The effect of synthesized
ligands (HL1, HL2) and complexes (1, 5) were tested on the mortality of entomopathogenic nematodes (EPN) (Heterorhabditis bacteriophora and
Steinernema carpocapsae). The study shows that the mortality of the nematodes increased with increasing concentrations of
copper(II) ion, ligands and complexes. Copper(II) ion was the most toxic for EPN.
相似文献
122.
M. Khalid A.F. Ismail C.T. Ratnam Y. Faridah W. Rashmi M.F. Al Khatib 《Radiation Physics and Chemistry》2010,79(12):1279-1285
Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1–7 phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50–200 kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M100) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M100 and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100 kGy, and a downward trend thereafter. Results on gel fraction further confirmed the crosslinking of SMR/CNT nanocomposites upon radiation. 相似文献
123.
Anti-reflection coatings of solar cells have been fabricated using different techniques. The techniques used include SiO2 thermal oxidation, ZnO/TiO2 sputtering deposition and porous silicon prepared by electrochemical etching. Surface morphology and structural properties of solar cells were investigated by using scanning electron microscopy and atomic forces microscopy. Optical reflectance was obtained by using optical reflectometer. I-V characterizations were studied under 80 mW/cm2 illumination conditions. Porous silicon was found to be an excellent anti-reflection coating against incident light when it is compared with another anti-reflection coating and exhibited good light-trapping of a wide wavelength spectrum which produced high efficiency solar cells. 相似文献
124.
Parvin Farshchi Seyed Khatiboleslam Sadrnezhaad Naser Moharram Nejad Mahmood Mahmoodi Leila Ibrahimi Ghavam Abadi 《Journal of nanoparticle research》2011,13(8):3511-3519
Using survey data, public awareness of and attitudes toward nanotechnology are examined in Iran (N = 759). Iran is a developing country with a national nanotechnology action plan for a ten year period starting from 2003
and has been active in the field of research and development of nanotechnology meanwhile. First, the results show that majority
of people are still not familiar with nanotechnology and perceived risks posed by this technology are not considered to be
a lot and most people feel its benefits outweigh the risks. The emotions toward this technology are of a hopeful and positive
nature and this technology is looked upon favorably in Iran. In particular, our results reveals that although the level of
trust is high specially in scientists to communicate the risks with the public, there are a great number who just have some
trust not quite a lot of it. Knowing that it is a hard and time-consuming effort to manage a nation’s view on nanotechnology,
extensive research as well as collaboration with other countries is needed to effectively communicate the risks in time. 相似文献
125.
Asma Rehman Muhammad Irfan Majeed Ayesha Ihsan Syed Zajif Hussain Saif-ur-Rehman Muhammad Afzal Ghauri Zafar M. Khalid Irshad Hussain 《Journal of nanoparticle research》2011,13(12):6747-6754
Abstract
A simple and environmentally benign green method is reported to decorate growing fungal hyphae with high loading of gold nanoparticles, which were initially produced using aqueous tea extract as a sole reducing/stabilizing agent. Inoculation of fungal spores in aqueous suspension of nanoparticles led to the growth of intensely red-coloured fungal hyphae due to the accumulation of gold nanoparticles. Heat treatment of these hybrid materials led to the formation of porous gold microwires. This report is thus an interesting example of using green and sustainable approach to produce nanostructured materials which have potential applications in catalysis, sensing and electronics. 相似文献126.
Khalid Mujasam Batoo 《Physica B: Condensed Matter》2011,406(3):382-387
The paper reports on the effect of Al substitution on the structural and electrical properties of bulk ferrite series of basic composition MnFe2−2xAl2xO4 (0.0≤x≤0.5) synthesized using solid state reaction method. XRD analysis confirms that all the samples exhibit single phase cubic spinel structure excluding presence of any secondary phase. The dielectric constant shows a normal behaviour with frequency, whereas the loss tangent exhibits an anomalous behaviour with frequency for all compositions. Variation of dielectric properties and ac conductivity with frequency reveals that the dispersion is due to Maxwell-Wagner type of interfacial polarization in general and hopping of charge between Fe+2 and Fe+3 as well as between Mn+2 and Mn+3 ions at octahedral sites. The complex impedance plane spectra shows the presence of two semicircles up to x=0.2, and only one semicircle for the higher values of x. The analysis of the data shows that the resistive and capacitive properties of the Mn ferrite are mainly due to processes associated with grain and grain boundaries. 相似文献
127.
A device for performing vector transmission spectroscopy on aqueous and polar solvent specimens at terahertz frequencies is presented. The device enables the direct measurement of the complex dielectric function across the terahertz band using a Fourier transform IR spectrometer for lossy solutions. Using microfluidic sampling, specimen handling is straightforward and direct measurements on polar specimens are made possible. The method is scalable to longer or shorter wavelengths. 相似文献
128.
Mahmood Alaghmandan Yemon Choi Ebrahim Samei 《Journal of Mathematical Analysis and Applications》2014
Let G be a restricted direct product of finite groups {Gi}i∈I, and let Z?1(G) denote the centre of its group algebra. We show that Z?1(G) is amenable if and only if Gi is abelian for all but finitely many i , and characterize the maximal ideals of Z?1(G) which have bounded approximate identities. We also study when an algebra character of Z?1(G) belongs to c0 or ?p and provide a variety of examples. 相似文献
129.
130.