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101.
Synthesis and surface engineering of magnetic nanoparticles for environmental cleanup and pesticide residue analysis: A review 下载免费PDF全文
Ranjeet Kaur Abshar Hasan Nusrat Iqbal Samsul Alam Mahesh Kr Saini Syed Kalbe Raza 《Journal of separation science》2014,37(14):1805-1825
In recent years, water pollution and pesticide accumulation in the food chain have become a serious environmental and health hazard problem. Direct determination of these contaminants is a difficult task due to their low concentration level and the matrix interferences. Therefore, an efficient separation and preconcentration procedure is often required prior to the analysis. With the advancement in nanotechnology, various types of magnetic core–shell nanoparticles have successfully been synthesized and received considerable attention as sorbents for decontamination of diverse matrices. Magnetic core–shell nanoparticles with surface modifications have the advantages of large surface‐area‐to‐volume ratio, high number of surface active sites, no secondary pollutant, and high magnetic properties. Due to their physicochemical properties, surface‐modified magnetic core–shell nanoparticles exhibit high adsorption efficiency, high rate of removal of contaminants, and easy as well as rapid separation of adsorbent from solution via external magnetic field. Such facile separation is essential to improve the operation efficiency. In addition, reuse of nanoparticles would substantially reduce the treatment cost. In this review article, we have attempted to summarize recent studies that address the preconcentration methods of pesticide residue analysis and removal of toxic contaminants from aquatic systems using magnetic core–shell nanoparticles as adsorbents. 相似文献
102.
Anil Saini Suresh 《合成通讯》2013,43(21):3655-3661
α-Amino nitriles are synthesized in a one-pot, three-component coupling of aldehydes, amines, and trimethylsilyl cyanide using a catalytic amount of LiBr at ambient temperature. 相似文献
103.
K. K. Saini C. P. Sharma Chander Kant D. K. Suri Subhas Chandra
S. P. Tiwari
《Physica C: Superconductivity and its Applications》1993,210(3-4):502-508Samples with nominal composition Tl2Ba2Cu1.2 (copper-rich Tl-2201) were calcined at various temperature, i.e. from 865 °C to 910°C and for various durations (10–20 h). The samples were sintered for 31/2 min at various temperatures. The X-ray powder diffraction pattern indicates that most of the Tl-Ba-Cu samples (Tl-2201) are single-phase materials. All the lines in the X-ray pattern are indexable on a tetragonal unit cell showing tetragonal symmetry having space group 14/mmm with a=3.86 Å C=23.11 ± 0.06 Å as unit cell parameters. R−T and AC susceptibility measurements show Tonc, from 90 to 104 K. There is an elongation of the c-axis (c=23.24 Å) for the sample showing the highest Tc. Wet chemical analysis confirms the deficiency of thallium. This suggests some substitution of Cu in place of thallium which leads to an increase in the average oxidation state of copper, responsible for the creation of holes (charge carriers). 相似文献
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Li Z Xu Y Ma X Dervishi E Saini V Biris AR Lupu D Biris AS 《Chemical communications (Cambridge, England)》2008,(28):3260-3262
We report on the role of CO(2) in improving carbon nanotube yield and crystallinity from catalytic chemical vapor deposition of hydrocarbons. 相似文献
108.
Romesh Kumar Kulbir Singh Heera Saini Sanjay Kumar 《Advances in Applied Clifford Algebras》2016,26(1):217-235
In this paper we study the bicomplex version of weighted Hardy spaces. Further, we describe reproducing kernels for the bicomplex weighted Hardy spaces. In particular, we generalize some results which holds for the classical weighted Hardy spaces. We also introduce the notion of bicomplex C*-algebra and discuss some of its properties. 相似文献
109.
Balwinder Saini Ashwani Kumar Ruby Rani Rajinder K. Bamezai 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(7):1350-1361
The density, viscosity and speed of sound of pure p-anisaldehyde and some alkanols, for example, methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol, 2-methylpropan-1-ol, and the binary mixtures of p-anisaldehyde with these alkanols were measured over the entire composition range at 303.15 K. From the experimental data, various thermodynamic parameters such as excess molar volume (VE), excess Gibbs free energy of activation (ΔG*E), and deviation parameters like viscosity (Δη), speed of sound (Δu), isentropic compressibility (Δκs), are calculated. The excess as well as deviation parameters are fitted to Redlich—Kister equation. Additionally, the viscosity data for the systems has been used to correlate the application of empirical relation given by Grunberg and Nissan, Katti and Chaudhari, and Hind et al. The results are discussed in terms of specific interactions present in the mixtures. 相似文献
110.
Ashwani Kumar Ruby Rani Anjana Gupta Balwinder Saini 《Physics and Chemistry of Liquids》2016,54(5):602-614
The density and speed of sound of L-arginine (0.025–0.2 mol kg?1) in aqueous + D-maltose (0–6 mass% of maltose in water) were obtained at temperatures of (298.15, 303.15 and 308.15) K. The apparent molar volume, limiting apparent molar volume, transfer volume, as well as apparent molar compressibility, limiting apparent molar compressibility, transfer compressibility, pair and triple interaction coefficients, partial molar expansibilities, coefficient of thermal expansion and also the hydration number, were calculated using the experimental density and speed of sound values. The results have been discussed in terms of solute–solute and solute–solvent interactions in these systems. Solute–solvent (hydrophilic–ionic group and hydrophilic–hydrophilic group) interactions were found to be dominating over solute–solute (hydrophobic–hydrophilic group) interactions in the solution, which increases with increase in maltose concentration. 相似文献