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In the present work new nitro substituted thioureas, and their copper complexes have been synthesized and characterized by FTIR and multinuclear NMR techniques. Some of the compounds namely 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐1), 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐2) and 1‐benzoyl‐3‐(2‐methoxy‐4‐nitrophenyl) thiourea (A‐2) have also been characterized by single crystal XRD. All the synthesized compounds have been screened for DNA binding potencies (using cyclic voltametry, UV‐vis spectroscopy) and free radical scavanging activities.  相似文献   
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The present work reports the redox mechanism of 5-hydroxynaphthalene-1,4-dione (HND), commonly known as juglone, in buffered aqueous media having 50% of ethanol. HND followed different mechanistic routes depending upon the pH of the media and more than one pKa were evaluated from the changes in the slope of the Ep vs. pH plot. The change of pH from acidic to neutral conditions was found to switch the mechanism from CEC to EE mechanism. Pulse techniques were utilized to determine the number of electrons involved in the oxidation and/or the reduction step and to ensure the nature of the redox process. Based upon the obtained results, an electrode reaction mechanism was proposed. Computational studies of HND supported the experimental results. UV-Visible spectroscopy was also employed for the detailed characterization of the compound in a wide range of pH and for the determination of its pKa.  相似文献   
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The HNO3‐mediated CH2 extrusion reactions of phenylacetic acid lead to one pot synthesis of unexpected commercially important product 4‐nitrobenzoic acid through the formation of 4‐nitrophenylacetic acid and 2‐nitrophenylacetic acid.  相似文献   
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We report a new tuneable alternating current (ac) electrohydrodynamics (ac‐EHD) force referred to as “nanoshearing” which involves fluid flow generated within a few nanometers of an electrode surface. This force can be externally tuned via manipulating the applied ac‐EHD field strength. The ability to manipulate ac‐EHD induced forces and concomitant fluid micromixing can enhance fluid transport within the capture domain of the channel (e.g., transport of analytes and hence increase target–sensor interactions). This also provides a new capability to preferentially select strongly bound analytes over nonspecifically bound cells and molecules. To demonstrate the utility and versatility of nanoshearing phenomenon to specifically capture cancer cells, we present proof‐of‐concept data in lysed blood using two microfluidic devices containing a long array of asymmetric planar electrode pairs. Under the optimal experimental conditions, we achieved high capture efficiency (e.g., approximately 90 %; % RSD=2, n=3) with a 10‐fold reduction in nonspecific adsorption of non‐target cells for the detection of whole cells expressing Human Epidermal Growth Factor Receptor 2 (HER2). We believe that our ac‐EHD devices and the use of tuneable nanoshearing phenomenon may find relevance in a wide variety of biological and medical applications.  相似文献   
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A metallic nanofluid is a suspension of metallic nanoparticles in a base fluid. Multi-metallic nanoparticles are a combination of two or more types of metallic particles. Such multi-metallic nanoparticles were suspended in water using an ultrasonic vibrator for different total volume fractions and different ratios of metallic/metallic nanoparticles. A transient hot wire setup was built to measure the thermal conductivity of the nanofluid at different temperatures. The experimental results were in good agreement with the results in the literature. Then, the experimental results were used as input data for an adaptive neural fuzzy inference system (ANFIS) to predict the thermal conductivity of the multi-metallic nanofluid. The maximum deviation between the ANFIS results and experimental measurements was 1 %. The predicted results and the experimental data were compared with other models. The ANFIS model was found to have good ability to predict the thermal conductivity of the multi-metallic nanofluid over the range of the experimental results.  相似文献   
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Nonlinear vortical structures and soliton formation are investigated for electron temperature gradient instability in a two-electron temperature non-Maxwellian magnetoplasma. The inhomogeneity in magnetic field is also considered. A new set of nonlinear equations, using transport equations of Braginskii”s model, are formulated to study the nonlinear structures. A modified linear dispersion relation of coupled electron temperature gradient (ETG) mode and electron acoustic wave is derived. The ETG instability is found to increase with increase in ηec value that increases with sharp density gradients. The results are applied to auroral region of earth's magnetosphere and the calculated values of the nonlinear electric field of fast solitary waves are found to be in agreement with the Viking satellite observations.  相似文献   
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Aromatic heterocyclic compounds have received a lot of interest due to their various important medicinal and biological applications. The broad synthetic investigation and functional usefulness of heterocyclic molecules is driving a surge in research interest. They are found in more than 90% of innovative medications and bridge the gap between biology and chemistry, where so much scientific discovery and application happens. Heterocycles are also useful in a variety of domains, including pharmaceutical chemistry, biochemistry, and others. In this article, quantitative structure-property relationship (QSPR) models is developed using sombor indices to predict fluorescence properties of aromatic hetero-cyclic species based on their structural features. This allows researchers to estimate the fluorescence behavior of new molecules without performing experimental measurements. As an application, we have computed the sombor indices for self-assembled supramolecular graphs made of terpyridine (TPE) and tetraphenylethylene (TPY) molecules that are produced as rosette cycles. This form of rosettes graph is used in electrical sensors, light emitting diodes, bioimaging and photoelectric devices, and so on. Tetraphenylethylene can be used to make fluorescent probes for next-generation sensing applications with typical induced aggregative emission behavior.  相似文献   
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