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41.
G. L. Baheti P. K. Khatri V. L. Meena L. R. Meghwal 《Journal of Radioanalytical and Nuclear Chemistry》1994,188(1):1-7
Fuel mix monitoring is important for optimum performance of vehicles. A variety of techniques used to monitor fuel mixes have not come into widespread use due to practical difficulties. Gamma attenuation has been found to be a potential technique for petroleum based fuel mix monitoring with certain limitations. 相似文献
42.
Polycrystalline samples of U-type hexaferrite series: (Ba1−3xLa2x)4Co2Fe36O60 with 0.10≤x≤0.20 in step of 0.05, are prepared by conventional solid state reaction route. Partial substitution of Ba2+ ions with La3+ ions enhances the electron hopping and reduces the magnetic interaction in the samples over the entire X-band frequencies; leading to wide band microwave absorption in all sample. Relative complex permittivity (εr=ε′−jε″) and permeability (μr=μ′−jμ″) of the prepared samples were measured using Vector Network Analyzer (VNA, Agilent PNA-L N5230A) for X-band (8.2-12.4 GHz) frequency range. The maximum absorption of 99.8% was obtained for x=0.10 sample for thickness tm=1.8 mm and all sample showed absorption ≥96%. The reflection loss (RL) calculated using the measured parameter (εr=ε′−jε″ and μr=μ′−jμ″) shows good agreement when compared with the return loss measured directly using VNA for sample x=0.20. The material can be expected to find relevance in suppression of electromagnetic interference (EMI) shielding and reduction of radar signatures. 相似文献
43.
A method for the determination of lead is described using thiol-functionalized gold nanoparticle. The detection method is based on the prevention of thiol-induced aggregation of gold nanoparticles by lead. Among six thiols, e.g., 4-mercapto-1-butanol, meso-2, 3-dimercaptosuccinic acid, mercaptosuccinic acid, 6-mercapto-1-hexanol, 4-(methylthio)-1-butanol, 1-propanethiol, four (4-mercapto-1-butanol, 6-mercapto-1-hexanol, 4-(methylthio)-1-butanol and 1-propanethiol) induced the aggregation of the gold nanoparticles which was measured by the change in absorbance at 520 and 650?nm. Prior incubation of the gold nanoparticles with lead decreased the 4-(methylthio)-1-butanol-induced aggregation of gold nanoparticles in a dose-dependent manner. A linear inverse relationship between the logarithmic concentration of lead and the ratio of absorbance at 650 to 520 was noted. The method has a dynamic range from 10?nM to 100?µM. However, metals such as mercury and chromium were more effective in comparison with lead in preventing the 4-methylthio-1-butanol-induced aggregation of gold nanoparticles. The method can be used for assessing the heavy metal load in water samples. 相似文献
44.
Dr. Santosh Kumar Meena Prof. Marialore Sulpizi 《Angewandte Chemie (International ed. in English)》2016,55(39):11960-11964
Directly manipulating and controlling the size and shape of metal nanoparticles is a key step for their tailored applications. In this work, molecular dynamics simulations were applied to understand the microscopic origin of the asymmetric growth mechanism in gold nanorods. Different factors influencing the growth were selectively included in the models to unravel the role of the surfactants and ions. In the early stage of the growth, when the seed is only a few nanometers large, a dramatic symmetry breaking occurs as the surfactant layer preferentially covers the (100) and (110) facets, leaving the (111) facets unprotected. This anisotropic surfactant layer in turn promotes anisotropic growth with the less protected tips growing faster. When silver salt is added to the growth solution, the asymmetry of the facets is preserved, but the Br? concentration at the interface increases, resulting in increased surface passivation. 相似文献
45.
The eccentric connectivity index \(\xi ^c(G)\) of a connected graph G is defined as \(\xi ^c(G) =\sum _{v \in V(G)}{deg(v) e(v)},\) where deg(v) is the degree of vertex v and e(v) is the eccentricity of v. The eccentric graph, \(G_e\), of a graph G has the same set of vertices as G, with two vertices u, v adjacent in \(G_e\) if and only if either u is an eccentric vertex of v or v is an eccentric vertex of u. In this paper, we obtain a formula for the eccentric connectivity index of the eccentric graph of a regular dendrimer. We also derive a formula for the eccentric connectivity index for the second iteration of eccentric graph of regular dendrimer. 相似文献
46.
The hydrodynamic flow between two eccentric cylinders is examined for small values of modified Reynolds number, porosity parameter and the non-dimensional slip velocity parameter in the presence of a radial magnetic field.The stream function and the pressure distribution are calculated and the results are presented graphically. 相似文献
47.
Varad Nagar Badal Mavry Vinay Aseri Apoorva Singh Kumud Kant Awasthi Garima Awasthi Mahipal Singh Sankhla 《Macromolecular Symposia》2024,413(1):2300034
This plastic waste degrades into nanoparticles, which are referred to as nanoplastics (NPs) pollutants, due to faulty reuse and recycling processes. These micro and nano plastic pollutants have the ability to absorb and interact with common pollutants and have a high surface area to volume ratio, which causes serious effects on the environment, especially plants. The size of pollutants is so small that they can cross the biological barriers and affect the cellular and molecular levels. Exposure to nanoplastics in photosynthetic species affects the growth and photosynthesis mechanism of the plants. Nanoplastics also affect humans through intake of the exposed plant materials. These pollutants can be plastic pellets, personal care products, marine coatings, synthetic textiles, etc. Plastic pollutants may enter the human body mainly through contaminated food and water. This review incorporates the toxicity of such pollutant and how their remediation is being done. The focus is also on the advancement of detection and remediation techniques. 相似文献
48.
49.
N-Phenylbenzamide-2,2′-dicarboxylic acid (PBDA) and its copper(II), nickel(II), cobalt (II), zinc(II) and manganese(II) chelates have been synthesized and characterized by their physical measurements, infrared and electronic spectra and magnetic moment data. In an acute anti-inflammatory test, the cobalt chelate was most active (31.1% inhibition) followed by the zinc and copper chelates, whereas the copper chelate (22.3% inhibition) was most active in an adjuvant arthritis test. Again the cobalt chelate was most active in the cotton-wad granuloma test. Gastric irritancy was markedly reduced after chelation by copper, followed in order by zinc, cobalt, manganese and nickel chelates. © 1997 John Wiley & Sons, Ltd. 相似文献
50.
Malbari Khushboo D. Chintakrindi Anand S. Ganji Lata R. Gohil Devanshi J. Kothari Sweta T. Joshi Mamata V. Kanyalkar Meena A. 《Molecular diversity》2019,23(4):927-951
Molecular Diversity - The rate of mutability of pathogenic H1N1 influenza virus is a threat. The emergence of drug resistance to the current competitive inhibitors of neuraminidase, such as... 相似文献