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排序方式: 共有270条查询结果,搜索用时 15 毫秒
41.
Selvaraj Munirasu Ashwini Deshpande Durairaj Baskaran 《Macromolecular rapid communications》2008,29(18):1538-1543
A simple method has been described to remove catalyst from the copper mediated atom transfer radical polymerization (ATRP) of benzyl methacrylate and methyl methacrylate in anisole at 25 °C using hydrated natural clay (sodium montmorillonite, Na‐clay). The method consists of (1) addition of hydrated clay (CuI/clay ≈ 5 wt.‐%) either during or after the polymerization, (2) oxidation of catalyst complex by exposing the terminated reaction mixture in air, and (3) filtration to obtain catalyst free polymer solution. A strong coordination of CuBr‐ligand complex onto hydrated clay (10 wt.‐% < H2O/clay < 30 wt.‐%) upon oxidation resulted in polymers with no or insignificant residual catalyst (<1.74 ppm), as determined by UV‐vis and atomic absorption spectroscopy. The recovered clay exhibited expanded intercalary layers and absence of polymer within it.
42.
Philippe Lewalle Sreenath K. Manikandan Cyril Elouard Andrew N. Jordan 《Contemporary Physics》2020,61(1):26-50
We review the continuous monitoring of a qubit through its spontaneous emission, at an introductory level. Contemporary experiments have been able to collect the fluorescence of an artificial atom in a cavity and transmission line, and then make measurements of that emission to obtain diffusive quantum trajectories in the qubit's state. We give a straightforward theoretical overview of such scenarios, using a framework based on Kraus operators derived from a Bayesian update concept; we apply this flexible framework across common types of measurements including photodetection, homodyne, and heterodyne monitoring and illustrate its equivalence to the stochastic master equation formalism throughout. Special emphasis is given to homodyne (phase-sensitive) monitoring of fluorescence. The examples we develop are used to illustrate basic methods in quantum trajectories, but also to introduce some more advanced topics of contemporary interest, including the arrow of time in quantum measurement, and trajectories following optimal measurement records derived from a variational principle. The derivations we perform lead directly from the development of a simple model to an understanding of recent experimental results. 相似文献
43.
Journal of Solid State Electrochemistry - Nanostructured electrode materials for supercapacitors have attracted research interest due to their high power density and long cycle life. Herein, porous... 相似文献
44.
Inhibition of mild steel corrosion by Morinda tinctoria leaves extract in sulphuric acid medium 总被引:1,自引:0,他引:1
The corrosion inhibition of mild steel in 0.5 M sulphuric acid by aqueous and acid extracts of leaves of Morinda tinctoria was studied using weight loss, colorimetric and electrochemical techniques. Results obtained indicate that both the extracts are effective in sulphuric acid medium and the efficiency decreases with increase in temperature. Added halide additives improve the efficiency of the inhibitor. From the thermodynamic, spectral, and surface analyses, the nature of adsorption has been found out. 相似文献
45.
Rajendran Manikandan Ramanathan Rajajeyaganthan Ganesan P. Shanmugavel Rajesh 《Journal of Thermal Analysis and Calorimetry》2021,143(4):3009-3021
Journal of Thermal Analysis and Calorimetry - In this work, considering the various practical concerns during storage, processing, handling and emission of flash powder used for making firecracker,... 相似文献
46.
Velu Manikandan Palanivel Velmurugan Palaniyappan Jayanthi Jung-Hee Park Woo-Suk Chang Yool-Jin Park Min Cho Byung-Taek Oh 《Research on Chemical Intermediates》2018,44(4):2489-2502
Green synthesis of TiO2 nanoparticles (NPs) from Prunus × yedoensis leaf extract (PYLE), and their application for removal of phosphate and their antibacterial activity, were studied for the first time. NPs were obtained using a green chemistry approach from 0.1 M TiO2 and PYLE at ratio of 1:1 (v/w). Initial confirmation of production of TiO2 NPs was provided by a color change from white to light yellow, then calcination was performed at 500 °C for 1 h. The TiO2 NPs were characterized using various analytical techniques such as ultraviolet–visible (UV–Vis) spectroscopy, X-ray diffraction analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy, UV–Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. The results indicated that the optimal amount of TiO2 NPs for removal of phosphate was 10 mg/l (10 ppm) with duration of 25 min. Furthermore, the antibacterial activity of TiO2 NPs was also investigated using two different bacteria (Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli) in aqueous medium. The results revealed highly efficient sunlight-driven photocatalytic and antibacterial activity of TiO2 NPs. 相似文献
47.
Murugesan Dinesh Subramanyam Deepika Rajendran HarishKumar Chinnadurai Immanuel Selvaraj Selvaraj Mohana Roopan 《Applied biochemistry and biotechnology》2018,185(2):450-463
The current study indicates that octyl-β-D-glucopyranoside (OGP) as a detergent which has the ability to make the lipid layer stiff. OGP was subjected for toxicity studies and in vitro cytotoxicty assays on cancerous HeLa and non-cancerous myoblasts H9c2 cell lines. Test against aquatic organisms were carried out in Artemia salina and LC50 values were calculated. Hemolytic activity tested for blood bio-compalibity showed hemolysis rate of 10–16%, followed by thrombolytic activity to burst the clots in blood. Also, the samples showed good lysis when compared to the standard streptokinase. Furthermore, α-amylase activity has been carried out to check the inhibition of α-amylase by the OGP. Finally, antibacterial activity has been tested against four different pathogens and their MIC values have been calculated. 相似文献
48.
K. M. Manikandan A. Yelilarasi P. Senthamaraikannan S. S. Saravanakumar Anish Khan Abdullah M. Asiri 《Journal of Solid State Electrochemistry》2018,22(12):3785-3797
The effect of polypyrrole (PPy) on the polyvinyl alcohol (PVA)-potassium iodide (KI)-iodine (I2) polymer electrolytes has been investigated and optimized to use in a dye-sensitized solar cell (DSSC). The different weight ratios of PVA: PPy (93: 2, 91: 4, 89: 6, 87: 8, and 85: 10 wt%) polymer electrolytes (PE) were prepared by solution casting. Structural, complex formation and surface roughness of the prepared electrolytes was confirmed by X-ray diffraction, FTIR, and atomic force microscopy (AFM) respectively. Conductivity plots of all polymer films showed increasing trend with temperature and concentration of PPy. The activation energy of the optimized system found to be 0.871 kJ mol?1. UV-visible spectrum was adopted to characterize the absorption spectra of the material revealed that increase in the absorbance with increasing PPy content and shifting the absorbance maximum towards lower energy. The indirect band gap decreased from 3.78 to 2.14 eV and direct band gap decreased from 3.88 to 2.71 eV. The EIS analyses revealed the lower charge transfer resistance of 3.029 Ω cm2 at the interface between CE and PE. The excellent performance was observed in the fabricated DSSCs using PVA (85%)/PPy (10%)/KI (5%)/I2 polymer electrolyte with a short-circuit current density of 11.071 mA cm?2, open-circuit voltage of 0.644 V, fill factor of 0.575, and photovoltaic conversion efficiency of 4.09% under the light intensity of 100 mW cm?2. Hence, the PPy content in polymer electrolyte influences the remarkable performance of low-cost DSSC. 相似文献
49.
2-O-tert-Butyldimethylsilyl-4,6-bis-O-pyrenoyl-myo-inositol-1,3,5-orthoformate (6) and 2-O-tert-butyldimethylsilyl-4-O-[4-(dimethylamino)benzoyl]-6-O-pyrenoyl-myo-inositol-1,3,5-orthoacetate (10) adopt conformationally restricted unstable chairs with five axial substituents. In the symmetrical diester 6, the two pi-stacked pyrenoyl groups are electron acceptor-donor partners, giving a strong intramolecular excimer emission. In the mixed ester 10, the pyrenoyl group is the electron acceptor and the 4-(dimethylamino)benzoyl ester is the electron donor, giving a strong intramolecular exciplex emission. The conformation of the mixed ester 10 was assessed using 1H NMR spectroscopy (1H-NOESY) and computational studies. which showed the minimum inter-centroid distance between the two aromatic systems to be approximately 3.9 A. Upon addition of acid, the orthoformate/orthoacetate trigger in 6 and 10 was cleaved, which caused a switch of the conformation of the myo-inositol ring to the more stable penta-equatorial chair, leading to separation of the aromatic ester groups and loss of excimer and exciplex fluorescence, respectively. This study provides proof of principle for the development of novel fluorescent molecular probes. 相似文献
50.
Ramanjulu Abinaya Selvaraj Elavarasan B. Binish Dr. K. Mani Rahulan Prof. Dr. Kalpattu K. Balasubramanian Dr. Kamaraj Manokaran Dr. Elumalai Varathan Dr. Baburaj Baskar 《European journal of organic chemistry》2023,26(4):e202201098
Herein we report a simple and efficient oxidative coupling of various aryl methyl amines with diverse coupling partners, such as o-phenylenediamine (benzene-1,2-diamine), 2-aminobenzenethiol and 2-aminobenzamide, to synthesize the corresponding heterocycles using scalable and reusable heterogeneous catalysts under visible light irradiation. A systematic investigation led to the synthesis of benzimidazoles, benzothiazoles and quinazolinones under air atmosphere in very good to excellent yields. The strategy is atom economical and found to be tolerance towards different functional groups, and wide range of substrate scope. Furthermore, the methodology was demonstrated for its suitability on scale up and reusability. The density functional theory (DFT) calculations and the analysis of band structures of pristine and Ba doped CoMoO4 systems showed that the doping of Ba in place of Co improved the catalytic performance of the system. 相似文献