排序方式: 共有73条查询结果,搜索用时 109 毫秒
41.
Sreejith Raveendran Neha Chauhan Yoshikata Nakajima Higashi Toshiaki Shunji Kurosu Yuji Tanizawa Ryugo Tero Yasuhiko Yoshida Tatsuro Hanajiri Toru Maekawa Pulickel. M. Ajayan Adarsh Sandhu D. Sakthi Kumar 《Particle & Particle Systems Characterization》2013,30(7):573-578
Highly conductive biocompatible graphene is synthesized using ecofriendly reduction of graphene oxide (GO). Two strains of non‐pathogenic extremophilic bacteria are used for reducing GO under both aerobic and anaerobic conditions. Degree of reduction and quality of bacterially reduced graphene oxide (BRGO) are monitored using UV–vis spectroscopy, X‐ray photoelectron spectroscopy, and Raman spectroscopy. Structural morphology and variation in thickness are characterized using electron microscopy and atomic force microscopy, respectively. Electrical measurements by three‐probe method reveal that the conductivity has increased by 104–105 fold from GO to BRGO. Biocompatibility assay using mouse fibroblast cell line shows that BRGO is non‐cytotoxic and has a tendency to support as well as enhance the cell growth under laboratory conditions. Hereby, a cost effective, non‐toxic bulk reduction of GO to biocompatible graphene for green electronics and bioscience application is achieved using halophilic extremophiles for the first time. 相似文献
42.
43.
Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation. 相似文献
44.
45.
In this work we provide a framework for modelling compact stars in which the interior matter distribution obeys a generalised Chaplygin equation of state. The interior geometry of the stellar object is described by a spherically symmetric line element which is simultaneously co-moving and isotropic with the exterior space–time being vacuum. We are able to integrate the Einstein field equations and present closed form solutions which adequately describe compact strange star candidates such as 4U 1538-52, PSR J1614-2230, Vela X-1 and Cen X-3 (Gangopadhyay et al, Mon. Not. R. Astron. Soc. 431, 3216 (2013)). 相似文献
46.
D. Bharathi Mohan K. Sreejith C.S. Sunandana 《Applied physics. B, Lasers and optics》2007,89(1):59-63
Silver thin films in the thickness range 2–10 nm produced by thermal evaporation onto glass substrates were systematically
iodized and carefully characterized by X-ray diffraction, atomic force microscopy (AFM) and optical absorption spectroscopy.
While the uniodized films are X-ray amorphous in keeping with their quasi-continuous nature and 2D islanded structure, briefly
iodized films showed characteristic beta AgI structure. Most interestingly, AFM of Ag films revealed uniform triangle-shaped
embryos whose shape does not change appreciably upon iodization. Optical absorption spectra of uniodized Ag films show intense
surface plasmon resonance (SPR) features with maxima at 440, 484 and 498 nm for the films of thicknesses 2, 5 and 10 nm, respectively,
with 5 nm films showing properties characteristic of optimally matched dielectric and electronic properties of the substrate
and sample, respectively. Finally, an interesting and unique SPR–exciton phase transition is observed as the ultra-thin films
are progressively iodized. These Ag and AgI films could be promising candidates for plasmonic and nanophotonic applications.
PACS 78.66.-w; 73.20.Mf; 71.35.Cc; 42.70; 68.37.Ps; 42.82.-m 相似文献
47.
The kinetics of basic hydrolysis of crystal violet (CV) in CTAB/KBr/C9OH micellar media was investigated under pseudo-first-order conditions. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of CV at 590?nm. It was observed that the pseudo-first-order rate constant increases with increase in C0. The enhancement of reaction rate with C0 is explained on the basis of dependence of reaction rate on micellar morphology. Further, the viscosity and DLS analysis supports nonanol-induced morphological transitions. Fluorescence spectroscopy has been used to understand dye–micelles interactions. The enhancement of fluorescence intensity of CV with C0 suggests an increase in dye–micelles interaction with C0. The concentration of surfactant and salt had a marked effect on reaction rate. The inhibition of reaction rate at high concentration of surfactant and salt is due to the ionic competition of OH? and Br? ions for the reaction center. The influence of [OH?] on CV hydrolysis was also investigated. The results show that the pseudo-first-order rate constant, k’, increases linearly with hydroxide ion concentration, indicating first-order dependence on [OH?]. 相似文献
48.
Osman
ZTÜRK Aydn HAMOLU Ouz Kaan
ZDEMR nci KARAASLAN Ali ems AHSEN 《Turkish Journal of Chemistry》2021,45(5):1336
A series of thin Pt-Co films with different metal ratios were deposited by using the sequential cosputtering directly on a commercial hydrophobic carbon paper substrate at room temperature and in ultra-high vacuum (UHV) conditions. Their electrocatalytic properties toward the oxygen reduction reaction were investigated in 0.5 M H2SO4 solution by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) on rotating disc electrode (RDE). The results showed that Pt particles, deposited by dc-magnetron gun, surround the large Co-clusters deposited by rf-magnetron gun. In addition, the increase of Co content led to an increase in the electrochemical active surface area (EASA) from 23.75 m2/gPt to 47.54 m2/gPt for pure Pt and Pt:Co (1:3), respectively, which corresponded the improvement of the utilization of Pt by a factor of 1.91. This improvement indicated that the sequential magnetron cosputtering was one of the essential technique to deposit homogeneous metal clusters with desirable size on the gas diffusion layer by adjustment plasma parameters. 相似文献
49.
Madhusudanan Sreejith P. Balamoorthy Elamathy M. Suresh Kumar Manivasagam Thirugnasambandam G. Batabyal Sudip K. 《Journal of Solid State Electrochemistry》2022,26(11):2411-2421
Journal of Solid State Electrochemistry - Cu2Fe1-xBaxSnS4 (CFBTS) thin films have been fabricated by the low-cost successive ionic layer and adsorption reaction (SILAR) method. The bandgap energies... 相似文献
50.
In this work, we explore a modern concept of transmetalation (metal exchange) for the effective recognition of aqueous Al(III) ion. Three different Ni(II) salen‐type Schiff base complexes with different spacer diimine groups were prepared for the metal exchange reaction. These probes recognize Al(III) both colorimetically as well as fluorimetrically. The efficiency in sensing is mainly due to the low emission characteristics of the respective Ni(II) complexes which results in enhanced emission on the formation of Al(III) complex. The geometry of the central Ni(II) metal ion in the probe plays a pivotal role in the sensing action with the highest sensitivity being shown by the Ni(II) metal center with distorted square pyramidal geometry. Further DFT calculations and the energetics involved in the sensing mechanism via the formation of Al(III) complexes substantiates the experimental results. 相似文献