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171.
172.
Here, thermal gradient effect on vibration of non-homogeneous orthotropic rectangular plate having bi-direction linearly thickness
variations is studied. The non-homogeneity is assumed to arise due to the variation in the density of the plate material.
Rayleigh Ritz method is used to evaluate the fundamental frequencies and deflection function. The two-dimensional thickness
variation is taken as the Cartesian product of linear variations along the two concurrent edges of the plate. Yet the method
used for the solution of present problem provides an approximate solution but it is quite convenient and authentic one. A two-term
deflection function is used. Frequency corresponding to first mode of vibration is calculated for clamped plate for different
values of temperature gradient, taper constants and non-homogeneity constant. In special cases, comparisons have been made
with results that are available in the literature. 相似文献
173.
Raghvendra Singh Sengar Steven J. Geib Archana Nigam Erik C. Wiener 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):o174-o175
The title compound, C26H45N3O8, is a bicyclic molecule; the seven‐membered diazepane ring has a twisted‐chair conformation and the six‐membered morpholine ring has a boat conformation. 相似文献
174.
A new synthesis of 2,3,5-trisubstituted pyrrolidines from the imino-aldols formed from Lewis acid-mediated reactions of (2-trimethylsilylmethyl)cyclopropyl ketones with benzylimines is described. The ring closure of the imino-aldols formed from the benzylimines of 2-chloro-, 2-fluoro-, and 2-trifluoromethylbenzaldehydes proceeds with predominantly 2,5-anti selectivity to generate the corresponding pyrrolidines in moderate yields. 相似文献
175.
Nandiraju V. S. Rao Manoj K. Paul Thatavarthi R. Rao Archana Prasad 《Liquid crystals》2002,29(9):1243-1246
The reaction of N -(4- n -alkoxysalicylidene)-4'- n -alkylanilines with freshly prepared lanthanide salts leads to mesomorphic terbium and dysprosium complexes exhibiting the smectic A phase. 相似文献
176.
The molecule acenaphth [1,2-a] has been studied theoretically to predict the ground state properties and π★ ← π transitions. It is seen that the theoretical results are in good agreement with experimental results. 相似文献
177.
The recordings of the amplitudes of radio beacon signals on 40, 140 and 360 MHz from ATS-6 (at 34° E longitude) recorded at
Ootacamund, India (11.43° N, 76.70°E, dip 4°N, elevation angle 41°) have revealed largest occurrence of scintillations for
about 60% of cases around 2200 hr during the nighttime, and two secondary peaks (25% of cases) around 0900 hr and 1400 hr
during the daytime.
During the daytime, the scintillation decreases approximately as the inverse of the frequency for higher frequencies while
for lower frequencies the law is valid till scintillation index at 40 MHz does not exceed 0.9. The temporal variation of daytime
scintillation shows impulsive character, the duration of activity lasts for 1–2 hours at a time.
During the nighttime, the scintillation decreases inversely with frequency for weak and moderate scintillation activity. The
scintillation index at 360 MHz becomes independent of that at 140 MHz when the index at 140 MHz exceeds 0.85. For the set
of frequencies 40–140 MHz, on some occasions scintillation index at 40 MHz is seen to be less than that at 140 MHz. The nighttime
scintillations are in general stronger and remain so for extended length of time.
The daytime scintillations are suggested to be due to blanketing or some other non-q type of sporadicE layer. The nighttime scintillations are most probably due to spreadF condition and the abnormal frequency variation of the scintillations may be due to multiple scattering layer during periods
of intense spreadF. 相似文献
178.
Archana S. Patole Shashikant P. Patole So-Young Jung Ji-Beom Yoo Jeong-Ho An Tae-Ho Kim 《European Polymer Journal》2012,48(2):252-259
Self-assembled graphene/carbon nanotube (CNT)/polystyrene hybrid nanocomposites were prepared by water-based in situ microemulsion polymerization. The resulting nanocomposites were used as filler in a host polystyrene matrix to form composite films. An admixture of the two types of carbon fillers provided better improvement in the thermal and mechanical properties compared to the neat polymer. The sheet resistance decreased progressively due to the formation of an extended conjugation network with the CNT bridging the gap between the graphene sheets coated with polymer nanoparticles. The details of the analysis are presented. 相似文献
179.
Kamil Woronowicz Saquib Ahmed Archana A. Biradar Ankush V. Biradar Dunbar P. Birnie Tewodros Asefa Robert A. Niederman 《Photochemistry and photobiology》2012,88(6):1467-1472
Current interest in natural photosynthesis as a blueprint for solar energy conversion has led to the development of a biohybrid photovoltaic cell in which bacterial photosynthetic membrane vesicles (chromatophores) have been adsorbed to a gold electrode surface in conjunction with biological electrolytes (quinone [Q] and cytochrome c; Magis et al. [2010] Biochim. Biophys. Acta 1798 , 637–645). Since light‐driven current generation was dependent on an open circuit potential, we have tested whether this external potential could be replaced in an appropriately designed dye‐sensitized solar cell (DSSC). Herein, we show that a DSSC system in which the organic light‐harvesting dye is replaced by robust chromatophores from Rhodospirillum rubrum, together with Q and cytochrome c as electrolytes, provides band energies between consecutive interfaces that facilitate a unidirectional flow of electrons. Solar I–V testing revealed a relatively high I sc (short‐circuit current) of 25 μA cm?2 and the cell was capable of generating a current utilizing abundant near‐IR photons (maximum at ca 880 nm) with greater than eight‐fold higher energy conversion efficiency than white light. These studies represent a powerful demonstration of the photoexcitation properties of a biological system in a closed solid‐state device and its successful implementation in a functioning solar cell. 相似文献
180.
In this paper an optical surface plasmon resonance (SPR) sensor with metamaterial for four and five layered structure is studied. The numerical results presented in this paper leads to a significant properties of metamaterials in sensing field. Computed results of SPR sensors using metamaterial are compared with conventional optical SPR sensors for four and five layered structure. It is seen that wider dynamic range or effective range of measurable refractive index increases when metamaterial layer is used. It is also verified that SPR sensor with metamaterial layer can dramatically enhance the resolution and reduce the reflectivity compared with conventional SPR. Validity of the magnetic field results is proved on the basis of smooth match of the fields in the different layers of the proposed optical SPR sensor. 相似文献