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111.
The UNESCO experiments on communication through television in the field of adult education conducted in France, Japan and India during the current and the previous decades demonstrated for the first time the potential of television for thr promotion of culture and education among the general masses. They also indicated that the tele-clubs, organized for group viewing in both urban and rural communities, could be an effective and adequate means for the purpose of communicating messages of social education. The results obtained from the special series of telecasts underscored the fact that the appeal of television was not restricted within national boundaries. The indirect co-operation of France, Japan and India-countries with different cultural backgrounds-toward the growth of a common institution like the tele-club was not merely a significant step in the effort to bring into reality an international exchange of ideas and experiments in the field of educational television; it also reinforced the concept of international communication through a global television system. 相似文献
112.
Bhattacharjee RR Das AK Haldar D Si S Banerjee A Mandal TK 《Journal of nanoscience and nanotechnology》2005,5(7):1141-1147
A novel gold nanoparticle-tripeptide (GNP-tripeptide) conjugate was prepared by peptide in-situ redox technique at ambient temperatureusing a newly designed tripeptide. This new tripeptide was nso designed that it has a C-terminus tyrosine residue, which reduced Au+3 to Au, and the terminally located free amino group was bound to the gold nanoparticle (GNP) surface resulting in highly stable Au colloids. The average diameter of the tripeptide-stabilized GNP is 8.7 +/- 2.3 nm. Tripeptide bound gold nanoparticles formed three-dimensional assemblies in the presence of an excess of similar or disimilar tripeptides. The aggregation of GNPs results in a red shift in the surface plasmon resonance from lambda max = 527 to 556 nm. The effect of the solvent, concentration, and nature of the tripeptides on the assembly process were investigated by TEM and UV-visible spectroscopy. 相似文献
113.
114.
The Indian Space Programme has the goals of launching a number of communication and remote sensing satellites for various
uses. The acoustic exposure testing of such space bound components and systems on ground is mandatory to check their ability
to withstand the extreme noise fields encountered during the trans-atmospheric flight to their final destinations in space.
This paper outlines the nature and origin of this acoustic field, need for acoustic testing, establishment of a versatile
groundbased high intensity acoustic-testing facility and its performance evaluation. The facility was set up as a joint project
between the National Aeronautical Laboratory (nal) and the Indian Space Research Organisation (isro). 相似文献
115.
116.
117.
Influence of altitudinal variation on the antioxidant potential of tartar buckwheat of Western Himalaya 总被引:1,自引:0,他引:1
Garima Kishore Shashi Ranjan Anjana Pandey Sanjay Gupta 《Food science and biotechnology》2010,19(5):1355-1363
In the present work, the effect of altitudinal variations on the total phenol, flavonoid, and antioxidant potential of seeds
and hull of Tartar buckwheat collected from 15 different locations of Western Himalaya has been investigated. Methanolic and
acetonic extracts of seed and hull powder showed significantly increasing amounts of total polyphenol content, and antioxidant
potential with rising altitude. Methanolic extract of seed and hull powder were found to have significantly greater polyphenol,
and antioxidant potential as compared to acetonic extract. The methanolic seed extract of Inderdhara (3,133 m) showed the
maximum total phenolic content 1,651 μg gallic acid equivalent/50 mg of dry weight. The methanolic seed extract of Inderdhara
showed the maximum antioxidant activity (77.29±1.2%) and antiradical activity (55.5±0.5%) also. The results of this study
exhibited good correlation with total polyphenol and antioxidant potential in all the samples followed by the increasing tendency
towards rising altitude. 相似文献
118.
The cure kinetics of medium reactivity unsaturated polyester resin formulated for Liquid Composite Molding process simulation was studied by Differential Scanning Calorimetry (DSC) under isothermal conditions over a specific range of temperature. For isothermal curing reactions performed at 100, 110, and 120°C, several influencing factors were evaluated using the heat evolution behavior of curing process. We propose two‐ and three‐parameter kinetic models to describe the cure kinetics of thermoset resins. Comparisons of the model solutions with our experimental data showed that the three‐parameter model was the lowest parameter model capable of capturing both the degree of cure and the curing rate qualitatively and quantitatively. The model parameters were evaluated by a non‐linear multiple regression method and the temperature dependence of the kinetic rate constants thus obtained has been determined by fitting to the Arrhenius equation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
119.
Rakesh Kumar Gupta Raghwesh Mishra Kingsuk Mukhopadhyay Rajesh Kumar Tiwari Ashok Ranjan Arvind Kumar Saxena 《SILICON》2009,1(2):125-129
Multiwalled carbon nanotubes (MWCNTs) have been coated with silicon carbide (SiC) using polycarbosilane as precursor in order
to improve their thermo oxidative stability. The polycarbosilane coated MWCNTs were heated to ~1300°C under an inert atmosphere
to generate the SiC coating. X-ray diffraction, energy dispersive X-ray analysis and scanning electron microscopy have confirmed
the formation of SiC on the MWCNTs. The retention of the tubular structure of the MWCNTs has been confirmed by transmission
electron microscopy. Thermogravimetric analysis has been performed to evaluate the thermo oxidative stabilities of coated
and virgin MWCNTs. Sonication studies have shown that the mechanical strength of the MWCNTs was increased after coating with
SiC. 相似文献
120.
In this paper, an electromagnetic bandgap (EBG) material in the range of 0.5–0.8 THz has been simulated with Arlon AR 600 (ε=6.0) as host material and air‐cylinders as the foreign embedded material. The effective dielectric permittivity of this material has been analyzed at the frequency range of 0.590–0.620 THz. The reduced effective dielectric permittivity substrate of thickness 50 µm has been used to design the microstrip antenna at 600 GHz with a novel approach. This proposed antenna shows an enhanced directivity of 15.1 dBi at 600 GHz frequency. To compare the analysis, the operating frequency has been scaled down by a factor of 100 and various results have been compared by using two different commercially available simulators CST Microwave Studio based on the finite integral technique and Ansoft HFSS based on the finite element method. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献