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211.
Han Chuanliang Li Meijia Haihambo Naem Babuna Pius Liu Qingfang Zhao Xixi Jaeger Carlo Li Ying Yang Saini 《Nonlinear dynamics》2021,106(2):1169-1185
Nonlinear Dynamics - Recurrent outbreaks of the coronavirus disease 2019 (COVID-19) have occurred in many countries around the world. We developed a twofold framework in this study, which is... 相似文献
212.
We consider the nonlocal version of the Weinberg Salam model (following Kleppe et al.) with a finite parameter Λ signifying a fundamental length scale. We calculate the extra contributions to the anomalous magnetic moment of the muon coming from the nonlocal structure in this model. We find that the nonlocal contribution can be comparable to weak contributions and goes to increase theoretical estimates. We use this calculation to determine the limit on the scale of nonlocality. We obtain the result 1/Λ ? 3 × 10?16cm, which could be improved when present experimental errors narrow down. 相似文献
213.
A. S. Brar Tripta Saini 《Journal of polymer science. Part A, Polymer chemistry》2005,43(13):2810-2825
Atom transfer radical polymerization conditions were optimized and standardized with different initiator and catalyst systems. Acrylonitrile/n‐butyl acrylate copolymers were synthesized with 2‐bromopropionitrile as the initiator and CuCl/Cu(0)/2,2′‐bipyridine as the catalyst system. Variations of the feed composition led to copolymers with different compositions. The number‐average molecular weight and the polydispersity index were determined by gel permeation chromatography. Quantitative 13C{1H} NMR was employed to determine the copolymer composition. The reactivity ratios calculated with a methodology based on the Mao–Huglin terminal model were rA = 1.30 and rB = 0.68 for acrylonitrile and n‐butyl acrylate, respectively. The reactivity ratios determined by the modified Kelen–Tudos method were rA = 1.29 ± 0.01 and rB = 0.67 ± 0.01. 13C{1H} NMR and distortionless enhancement by polarization transfer (DEPT‐45, 90, and 135) were used to distinguish methyl, methylene, methine, and quaternary carbon resonance signals. The overlapping and broad signals of the copolymers were assigned completely to various compositional and configurational sequences by the correlation of one‐dimensional (1H, 13C{1H}, and DEPT) and two‐dimensional (heteronuclear single quantum coherence, total correlation spectroscopy, and heteronuclear multibond correlation) NMR spectral data. The complete spectral assignments of carbonyl and nitrile carbons were performed with the help of heteronuclear multibond correlation spectra. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2810–2825, 2005 相似文献
214.
A. Valletta A. Bianconi A. Perali N.L. Saini 《Zeitschrift für Physik B Condensed Matter》1997,104(4):707-713
The superconducting gap, the critical temperature and the isotope coefficient in a superlattice of metallic quantum stripes is calculated as a function of the electron number density. We show that it is possible to design a particular artificial superlattice of quantum stripes that exhibits the curves of T c and of the isotope coefficient as a function of the charge density as in cuprate superconductors. The shape of the superlattice is designed in order to tune the chemical potential near the bottom of the third subband for an electron number density of ρ ~ 5:810-2Å-2. The superconducting critical temperature shows a resonant amplification as a function of electron number density ρ with a maximum at a critical value ρ c. The isotope coefficient shows a sharp drop from a regime where α > 0:5 at ρ < ρ c to a regime where α < 0:2 at ρ ≥ ρ c. The underdoped and overdoped regime in cuprate superconductors is associated with a transition from a quasi 1D behavior for ρ > ρ c to quasi 2D behavior for ρ < ρ c with opening of a pseudogap at ρ ~ ρ c. 相似文献
215.
216.
Adsorption studies on the removal of Vertigo Blue 49 and Orange DNA13 from aqueous solutions using carbon slurry developed from a waste material 总被引:12,自引:0,他引:12
Waste material (carbon slurry), from fuel oil-based generators, was used as adsorbent for the removal of two reactive dyes from synthetic textile wastewater. The study describes the results of batch experiments on removal of Vertigo Blue 49 and Orange DNA13 from synthetic textile wastewater onto activated carbon slurry. The utility of waste material in adsorbing reactive dyes from aqueous solutions has been studied as a function of contact time, temperature, pH, and initial dye concentrations by batch experiments. pH 7.0 was found suitable for maximum removal of Vertigo Blue 49 and Orange DNA13. Dye adsorption capacities of carbon slurry for the Vertigo Blue 49 and the Orange DNA13 were 11.57 and 4.54 mg g(-1) adsorbent, respectively. The adsorption isotherms for both dyes were better described by the Langmuir isotherm. Thermodynamic treatment of adsorption data showed an exothermic nature of adsorption with both dyes. The dye uptake process was found to follow second-order kinetics. 相似文献
217.
Sukhjinder Singh Deepika Saini S. K. Mehta Ravneet Kaur Valeria Ferretti 《Journal of Thermal Analysis and Calorimetry》2014,117(1):473-480
Alkaline earth metal trichloroacetates M(O2CCCl3)2·nH2O, where M = Be (1), n = 4; M = Mg (2), n = 6; M = Ca (3) or Sr (4) or Ba (5), n = 4, were synthesized and their thermal behavior analyzed using thermogravimetric analysis (TG/DTG/DSC). A critical examination was made for the apparent activation energy by means of non-isothermal kinetic methods employing multiple heating rates. A systematic and comparative study of thermal decomposition was carried out at different heating rates i.e., 5, 10, 15, and 20 °C min?1 for various trichloroacetates synthesized. It was observed that the Ca, Sr, and Ba trichloroacetates decompose preferentially to respective metal halides while Be and Mg compounds decompose to metal and metal oxide, respectively. The composition of the final residues was also confirmed using FT-IR spectroscopy. The activation energy follows the order: Mg > Ca > Sr > Ba, Be being the exception. Results reveal that each metal trichloroacetate decomposes through its unique thermolysis mechanism. 相似文献
218.
219.
Balwinder Saini Bindu Rani Rajinder K. Bamezai 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(1):47-51
The density, viscosity and ultrasonic velocity for β-alanine solutions in aqueous and aqueous methanol medium at different concentrations has been determined at 308.15 K. The experimentally obtained data were used to evaluate the apparent molal volume and apparent molal adiabatic compressibility. The related thermodynamic parameters like partial molal volume as well as partial molal adiabatic compressibility at infinite dilution along with their corresponding constants S v and S k , respectively, give an insight to the nature of molecular interactions. The viscosity coefficient has also been calculated using Jones-Dole equation. 相似文献
220.
Copolymerization of acrylonitrile (AN) and ethyl methacrylate (EMA) using copper‐based atom transfer radical polymerization (ATRP) at ambient temperature (30 °C) using various initiators has been investigated with the aim of achieving control over molecular weight distribution. The effect of variation of concentration of the initiator, ligand, catalyst, and temperature on the molecular weight distribution and kinetics were investigated. No polymerization at ambient temperature was observed with N,N,N′,N′,N″‐pentamethyldiethylenetriamine (PMDETA) ligand. The rate of polymerization exhibited 0.86 order dependence with respect to 2‐bromopropionitrile (BPN) initiator. The first‐order kinetics was observed using BPN as initiator, while curvature in first‐order kinetic plot was obtained for ethyl 2‐bromoisobutyrate (EBiB) and methyl 2‐bromopropionate (MBP), indicating that termination was taking place. Successful polymerization was also achieved with catalyst concentrations of 25 and 10% relative to initiator without loss of control over polymerization. The optimum [bpy]0/[CuBr]0 molar ratio for the copolymerization of AN and EMA through ATRP was found to be 3/1. For three different in‐feed ratios, the variation of copolymer composition (FAN) with conversion indicated toward the synthesis of copolymers having slight changes in composition with conversion. The high chain‐end functionality of the synthesized AN‐EMA copolymers was verified by further chain extension with methyl acrylate and styrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1975–1984, 2006 相似文献