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81.
Kinetics and Catalysis - The Haldane kinetic model of phenol biodegradation in batch operation is discussed. This kinetic is most commonly used to describe the dependence of specific growth rate on... 相似文献
82.
Dr. Rajendran Manikandan Dr. Ravindra S. Phatake Prof. N. Gabriel Lemcoff 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(29):e202200634
The photochemical isomerization of α,β- to β,γ-unsaturated ketones through a 1,5-hydrogen atom transfer mechanism under mild conditions with high efficiency and selectivity is reported. The reaction is carried out in the absence of metal catalysts or other additives, and its stereoselectivity can be tuned by selecting appropriate solvent mixtures. The reaction‘s scope and tolerance towards functional groups, including light-sensitive halogens, free acids and alcohols, were studied, providing reliable access to a wide variety of β,γ-unsaturated ketones. This methodology details the deconjugation of a wide range of unsaturated ketones and, when combined with olefin metathesis, provides an efficient process for either dehomologation or one-carbon double-bond migration of terminal alkenes. 相似文献
83.
Patel Akash Pravinkumar Bhatnagar Divyang kumar Rajendran Senthil Prabhu Sethuramalingam 《Journal of Thermal Analysis and Calorimetry》2022,147(1):675-684
Journal of Thermal Analysis and Calorimetry - Due to the low performance observed during natural convection with fluids such as air and water, nanofluid research was carried out to analyse them for... 相似文献
84.
Nanocrystalline cadmium doped tin oxide (SnO2) powders of about 2.5–4.5 nm in size have been synthesized by using different solvents via sol–gel method. The obtained samples
were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy
(SEM), Energy dispersive X-ray analysis (EDX), Transmission electron spectroscopy (TEM), UV-Vis absorption and Photoluminescence
(PL) spectroscopy. The PL emission spectra revealed that the band centered at 452 nm might be related with oxygen vacancies.
A spherical, small rod and slice like morphologies of the prepared Cd-SnO2 nanoparticles were observed in the SEM and TEM studies. The presence of Cd modifies the structural, morphological and optical
properties of the tin oxide nanoparticles. 相似文献
85.
Poly(vinyl acetate), poly(vinylidene fluoride–hexafluoropropylene), lithium perchlorate salt, and the different plasticizer-based
gel polymer electrolytes were prepared by solvent-casting technique. The structural and the complex formation have been confirmed
by X-ray diffraction spectroscopic analysis. Thermal stability of the different plasticizer-added electrolyte films has been
analyzed by means of thermogravimetric analysis. Ionic conductivity of the electrolyte samples has been found as a function
of temperature and the plasticizers. Among the various plasticizers, ethylene carbonate-based complexes exhibit maximum ionic
conductivity value of the order of 10−4 Scm−1. Finally, the microstructure of the maximum ionic conductivity sample has been depicted with the help of scanning electron
microscope analysis. 相似文献
86.
A novel group of polymer blend electrolytes based on the mixture of poly(vinyl acetate) (PVAc), poly(vinylidene fluoride-hexafluoropropylene)
(PVdF-HFP), and the lithium salt (LiClO4) are prepared by solvent casting technique. Ionic conductivity of the polymer blend electrolytes has been investigated by
varying the PVAc and PVdF-HFP content in the polymer matrix. The maximum ionic conductivity has been obtained as 0.527 × 10−4 Scm−1 at 303 K for PVAc/PVdF-HFP ((25/75) wt.%)/LiClO4 (8 wt.%). The complex formations ascertained from XRD and FTIR spectroscopic techniques and the thermal behavior of the prepared
samples has been performed by DSC analysis. The surface morphology and the surface roughness are studied using SEM and AFM
scanning techniques respectively. 相似文献
87.
We investigate the exact bright and dark solitary wave solutions of an effective 1D Bose-Einstein condensate (BEC) by assuming that the interaction energy is much less than the kinetic energy in the transverse direction. In particular, following the earlier works in the literature Pérez-García et al. (2004) [50], Serkin et al. (2007) [51], Gurses (2007) [52] and Kundu (2009) [53], we point out that the effective 1D equation resulting from the Gross-Pitaevskii (GP) equation can be transformed into the standard soliton (bright/dark) possessing, completely integrable 1D nonlinear Schrödinger (NLS) equation by effecting a change of variables of the coordinates and the wave function. We consider both confining and expulsive harmonic trap potentials separately and treat the atomic scattering length, gain/loss term and trap frequency as the experimental control parameters by modulating them as a function of time. In the case when the trap frequency is kept constant, we show the existence of different kinds of soliton solutions, such as the periodic oscillating solitons, collapse and revival of condensate, snake-like solitons, stable solitons, soliton growth and decay and formation of two-soliton bound state, as the atomic scattering length and gain/loss term are varied. However, when the trap frequency is also modulated, we show the phenomena of collapse and revival of two-soliton like bound state formation of the condensate for double modulated periodic potential and bright and dark solitons for step-wise modulated potentials. 相似文献
88.
Alternating copolymers containing phosphorus were prepared from 2-phenyl-1,3,2-dioxaphospholane, 2-phenyl-4-oxo-5,6-benzo-1,3,2-dioxaphosphorinane with ethylene oxide and γ-butyrolactone. The polymerisations took place without added catalyst. The copolymers were characterised by i.r. and NMR spectroscopy, viscosity measurements and phosphorus estimation. Key intermediates responsible for initiation and propagation of the copolymerisations were isolated and the mechanism of copolymerisation is discussed. 相似文献
89.
Satheesh Kumar Palanisamy Velusamy Arumugam Samyutha Rajendran Anandhan Ramadoss Subash Nachimuthu Magesh Peter D. 《Natural product research》2019,33(14):2120-2124
The chemical diversity of three macroalgae (Ulva reticulata, Sargassum wightii, Gracilaria sp) were determined using the GC-MS method with principal component analysis (PCA) and their potential efficacy against human pathogens and cervical carcinoma cells evaluated using MTT bioassay method. Our results showed that >30 metabolites were detected in three seaweeds, among these, steroids and fatty acids are the most dominant chemical group that highly contributes to discriminate this species. The PCA of GC-MS mass spectral variables showed a clear discrimination between three different species based on the phytochemical diversity of seaweeds. The extracts of U. reticulata exhibited anti-microbial activity with Pseudomonas aeruginosa (6.00?mm) and showed potential anti-proliferative activity against the HeLa cells (IC50 37?µmol/L) at concentration 1–50?µM treatment. Results of this study concluded that PCA analysis of mass spectral variables could be utilized as a reliable tool for species discrimination and chemotaxonomic classification of seaweeds. 相似文献
90.
Tellurite containing vanadate (50−x)V2O5–xBi2O3–50TeO2 glasses with different bismuth (x=0, 5, 10, 15, 20 and 25 wt%) contents have been prepared by rapid quenching method. Ultrasonic velocities (both longitudinal and shear) and attenuation (for longitudinal waves only) measurements have been made using a transducer operated at the fundamental frequency of 5 MHz in the temperature range from 150 to 480 K. The elastic moduli, Debye temperature, and Poisson’s ratio have been obtained both as a function of temperature and Bi2O3 content. The room temperature study on ultrasonic velocities, attenuation, elastic moduli, Poisson’s ratio, Debye temperature and glass transition temperature show the absence of any anomalies with addition of Bi2O3 content. The observed results confirm that the addition of Bi2O3 modifier changes the rigid formula character of TeO2 to a matrix of regular TeO3 and ionic behaviour bonds (NBOs). A monotonic decrease in velocities and elastic moduli, and an increase in attenuation and acoustic loss as a function of temperature in all the glass samples reveal the loose packing structure, which is attributed to the instability of TeO4 trigonal bipyramid units in the network as temperature increases. It is also inferred that the glasses with low Bi2O3 content are more stable than with high Bi2O3 content. 相似文献