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11.
Babasaheb J. Waghmode Sagar H. Patil Mandar M. Jahagirdar Virendra S. Patil Rupali P. Waichal Dipalee D. Malkhede Shivaram D. Sathaye Kashinath R. Patil 《Colloid and polymer science》2014,292(5):1079-1089
It is well accepted that the morphology of the nanomaterials has great effect on the properties and hence their applications. Therefore, morphology of materials has become a focus of research in the scientific world. The present study shows that interfacial polymerization and subsequent self-assembly provides a control over the morphology, nanorod/nanosheet, of polyaniline (PANI) films synthesized by liquid–liquid interface reaction technique and solid–liquid interface reaction technique. The synthesized PANI films and its particulate structure are characterized by using various spectroscopic techniques such as UV–visible, ATR-IR, Raman and XPS. The study confirmed the formation, the structure, the size and shape of particles and morphology of PANI by using analytical techniques namely, SAED, SEM and TEM. An important observation is that doping with HCl significantly improves the nanorod formation at the interface. The doped PANI electrode exhibits a higher area with rectangular shape in CV cycle and better cycle stability when compared with the performance of undoped PANI films. We believe that the results of these studies can give valuable leads to manoeuvre formation of PANI films with desired morphology for various applications. Figure
Time and temperature-dependent morphology of PANI layer leading to the formation of one/two-dimensional structures namely, PANI rods/sheets, is achieved by monitoring of self-assembly of nano particulate film formed at liquid–liquid/solid–liquid interfaces 相似文献
12.
Deepa Sathian Rupali Rohatgi V. Jayalakshmi P. K. Marathe Sarala Nair R. V. Kolekar G. Chourasiya S. Kannan 《Indian Journal of Physics》2009,83(6):863-869
CR-39 Solid State Nuclear Track Detecting foils (SSNTD), along with 1 mm thick polyethylene radiator, sealed in triple laminated
pouches, are used for country wide Fast Neutron Personnel Monitoring in India. With the present system of processing by elevated
temperature electrochemical etching (ETECE) and evaluation using automatic image analysis, only 16 foils are processed at
a time and it is useful over the dose equivalent range 0.2 mSv to 10 mSv. It has been reported that, by processing CR-39 of
good detection efficiency by chemical etching at elevated temperature, more numbers of foils can be processed simultaneously.
In the present study, CR-39 foils from Pershore Moulding (UK) have been chemically etched using 7 N KOH under various conditions
of temperature and etching durations and evaluated using high magnification microscope. The duration of chemical etching,
has been optimized at a constant temperature of 60°C for chemical etching process. The characteristics of the chemically etched
CR-39 foils are compared with the characteristics of the CR-39 foils processed by the existing system of ETECE and the detailed
results are presented in the full text of the paper. It has been observed that by chemical etching process, the dose equivalent
range of CR-39 foils can be extended above 60 mSv.
相似文献
13.
14.
Recently a novel phase of ZnO has been synthesized which is analogous to α-boron nitride, although more three dimensional, and consists of planar hexagonal sheets of ZnO. Examining the dynamic stability of the structure, we find unstable phonon modes over a considerable part of the Brillouin zone. Local-density approximation (LDA) and generalized gradient approximation level calculations have usually been able to predict the structural stability of s-p bonded systems. The failure in the present case is a surprise and is traced to the self-interaction error which incorrectly locates the localized Zn d states in the valence band of ZnO. Correcting for this with a Hubbard-like U on the Zn d states, the optimized structure is predicted to be stable. This highlights the fact that the large bond length contraction that one finds in going from sp(3)- to sp(2)-type bonding results in an increased necessity to correct for self-interaction errors. 相似文献
15.
Thin films of ZnO-SnO2 composites have been deposited on Si(1 0 0) and glass substrates at 500 °C by pulsed laser ablation using different composite targets with ZnO amount varying between 1 and 50 wt%. The effect of increasing ZnO-content on electrical, optical and structural properties of the ZnO-SnO2 films has been investigated. X-ray diffraction analysis indicates that the as-deposited ZnO-SnO2 films can be both crystalline (for ZnO <1 wt%) and amorphous (for ZnO ≥ 10 wt%) in nature. Atomic force microscopy studies of the as-prepared composite films indicate that the surfaces are fairly smooth with rms roughness varying between 3.07 and 2.04 nm. The average optical transmittance of the as-deposited films in the visible range (400-800 nm), decreases from 90% to 72% for increasing ZnO concentration in the film. The band gap energy (Eg) seems to depend on the amount of ZnO addition, with the maximum obtained at 1 wt% ZnO. Assuming that the interband electron transition is direct, the optical band gap has been found to be in the range 3.24-3.69 eV for as-deposited composite films. The lowest electrical resistivity of 7.6 × 10−3 Ω cm has been achieved with the 25 wt% ZnO composite film deposited at 500 °C. The photoluminescence spectrum of the composite films shows a decrease in PL intensity with increasing ZnO concentration. 相似文献
16.
Debajyoti Choudhury Saurabh D. Rindani B. Ananthanarayan K. R. S. Balaji Debajyoti Choudhury Manuel Drees Shashikant Dugad Gautam Dutta Sukanta Dutta Naveen Gaur Ambar Ghosal Walter Grimus Ernest Ma Shubhendra Mohanty P. N. Pandita M. K. Parida Subhendu Rakshit Saurabh D. Rindani D. P. Roy Probir Roy Sarira Sahu N. N. Singh Sudhir K. Vempati Francesco Vissani 《Pramana》1998,51(1-2):305-311
This report summarises the activities of the working group on ‘Physics beyond the Standard Model’. The results of investigations
in incorporatingR-parity in grand unification, the possibility of a light charged Higgs boson in extension of MSSM and radiative generation
of neutral vector boson self-couplings within the MSSM are described. Also given is an account of activities in neutrino physics,
namely a proposal for a study of the atmospheric muon anomaly in deep underground mines, a field theoretic study of neutrino
oscillations and a mechanism to generate appropriate masses of three active plus one sterile neutrino species. 相似文献
17.
D. P. Bhattacharyya R. Rakshit B. Basu P. Pal S. Biswas N. Durgaprasad 《Il Nuovo Cimento C》1992,15(3):341-347
Summary A search has been made on the charge-changing partial cross-sections by using 0.927 GeV/n238U ion from LBL BEVALAC projected at an angle 30° on27Al target and CR-39 (DOP) was used as analyser. The irradiated plastic sheets were duly etched for one hour in 6.25N NaOH
solution and about 1680 cone lengths at both the surfaces of the CR-39 (DOP) sheets were optically measured. The cone length
distribution exhibits the existence of U fragments in the charge range 84≤Z≤91 and the estimated partial cross-sections range from 60 to 400 mb. The present data are in accord with the fit to the extrapolated
data of Binnset al. 相似文献
18.
The interfacial and thermodynamic properties of a non-ionic surfactant, poly[oxyethylene(10)] lauryl ether, [C12H25(OCH2CH2)10OH], in aqueous solution in the presence of amino acids have been investigated. Critical micelle concentrations (cmcs) were determined by surface tension measurements at different additive concentrations and temperatures using a du Nouy tensiometer. From the surface tension data, the surface excess concentration (F), the minimum area per molecule (Amin), and the surface pressure at the cmc(?cmc) were evaluated. Thermodynamic parameters of adsorption and micellization were evaluated and discussed. The other solution properties of this surfactant like the cloud point viscosity, and foaming have been determined in the presence of different concentrations of alanine and glycine. 相似文献
19.
Rakshit S Grohmann C Besset T Glorius F 《Journal of the American Chemical Society》2011,133(8):2350-2353
An efficient Rh(III)-catalyzed oxidative olefination by directed C-H bond activation of N-methoxybenzamides is reported. In this mild, practical, selective, and high-yielding process, the N-O bond acts as an internal oxidant. In addition, simply changing the substituent of the directing/oxidizing group results in the selective formation of valuable tetrahydroisoquinolinone products. 相似文献
20.
A.B. Rakshit 《Chemical physics letters》1979,66(2):373-375
The rate coefficient and the product distribution have been determined for the reaction CO2-CO+2 with sulfur dioxide. 相似文献