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51.
52.
Perumal Rajakumar Kathiresan Visalakshi Shanmugam Ganesan Pichai Maruthamuthu Samuel Austin Suthanthiraraj 《Journal of Materials Science》2012,47(4):1811-1818
Novel pyreno-chalcone dendrimers 1, 2, and 3 were synthesized and their ability to act as an additive in the redox couple (I−/I3
−) of dye-sensitized nanocrystalline TiO2 solar cell has been tested. The redox couple doped with pyreno-chalcone dendrimer 3 gave a short circuit photocurrent density (J
sc) of 7.40 mA/cm2, open circuit voltage (V
oc) of 820 mV, and a fill factor of 0.51, corresponding to an overall conversion efficiency (η) of 7.89% under 40 mW/cm2 irradiation. 相似文献
53.
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55.
A. Kalaivanan S. Perumal N. Neelakanda Pillai K.R. Murali 《Materials Science in Semiconductor Processing》2011,14(2):94-96
Zinc oxide (ZnO) films were deposited by sol–gel dip coating using the acrylamide route. The films were doped with different concentrations of gallium in the range 250–1200 ppm. The films exhibited hexagonal structure. The grain size decreased from 100 to 10 nm as the dopant concentration increased. The resistivity of the doped samples decreased from 103 to 3×10−3 Ω cm. The band gap value shifted towards the short-wavelength region as the dopant concentration increased. XPS studies indicated doping of Ga in ZnO 相似文献
56.
P. Saravanan G. Venkata RamanaK. Srinivasa Rao B. SreedharA. Perumal 《Thin solid films》2011,519(19):6290-6296
Thin magnetic films of Sm-Co nanocrystallites on SiO2 substrate were fabricated using spin coating deposition. In a typical synthesis, precursor of Sm-Co oleate complex was spin coated onto a SiO2 substrate in the form of precursor films and subsequently they were subjected to reductive annealing at 773 K for 2 h, so as to crystallize Sm-Co phase in the films. It has been found that the reductive annealing temperature (573-773 K) played a critical role on the nucleation and formation of Sm-Co crystalline phases; while the spinning speed (3000-5000 rpm) has a significant effect in controlling the film thickness, which in turn affects the particle diameter, inter-particle distance and packing density of the Sm-Co nanocrystallites. Coercivity values of 27.9, 23.9 and 18.7 kA⋅m− 1 and magnetization values of 2.89, 2.51 and 2.21 × 10− 6 A⋅m2 were achieved for the Sm-Co films with thicknesses of 345 (3000 rpm), 264 (4000 rpm) and 162 nm (5000 rpm), respectively. Further, these hard magnetic properties could be significantly improved by subjecting the Sm-Co films to post-annealing at 873 K. 相似文献
57.
The cloud computing environment is a real‐time communication network that involves a large number of systems connected in a distributed fashion, for which resources are available on demand. In recent years, due to the enormous growth of data and information, data maintenance tasks involve a major effort in information technology (IT) industries. So, IT industries are concentrating on the cloud computing environment in order to maintain their data and manage their resources. Owing to the increase in the number of data centres, which have an impact on electrical energy cost, peak power dissipation, cooling and carbon emission, power‐conservation‐based resource management is essential. A best‐fit heuristic job placement algorithm is proposed in this paper in order to increase the job allocation percentage, a worst‐fit heuristic virtual machine (VM) placement algorithm is also proposed in order to place the VMs over the physical machines (PMs) thereby reducing the number of the latter allotted, and a server consolidation algorithm is proposed in order to improve power conservation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
58.
Perumal Naveenkumar Munisamy Maniyazagan Nayoung Kang Hyeon-Woo Yang Woo-Seung Kang Sun-Jae Kim 《International journal of molecular sciences》2022,23(22)
The construction of carbon-coated heterostructures of bimetallic sulfide is an effective technique to improve the electrochemical activity of anode materials in lithium-ion batteries. In this work, the carbon-coated heterostructured ZnS-FeS2 is prepared by a two-step hydrothermal method. The crystallinity and nature of carbon-coating are confirmed by the investigation of XRD and Raman spectroscopy techniques. The nanoparticle morphology of ZnS and plate-like morphology of FeS2 is established by TEM images. The chemical composition of heterostructure ZnS-FeS2@C is discovered by an XPS study. The CV results have disclosed the charge storage mechanism, which depends on the capacitive and diffusion process. The BET surface area (37.95 m2g−1) and lower Rct value (137 Ω) of ZnS-FeS2@C are beneficial to attain higher lithium-ion storage performance. It delivered a discharge capacity of 821 mAh g−1 in the 500th continuous cycle @ A g−1, with a coulombic efficiency of around 100%, which is higher than the ZnS-FeS2 heterostructure (512 mAh g−1). The proposed strategy can improve the electrochemical performance and stability of lithium-ion batteries, and can be helpful in finding highly effective anode materials for energy storage devices. 相似文献
59.
Prakasam Thirumurugan Duraisamy Muralidharan Paramasivan T. Perumal 《Dyes and Pigments》2009,81(3):245-253
A simple and facile method for the synthesis of 2,3-bis[(E)-2-aryl vinyl]-quinoxaline and 2,3-bis[(E)-2-aryl vinyl]-pyrido(2,3-b)pyrazine is described. Condensation of cinnamils with 1,2-diaminobenzene and 2,3-diaminopyridine in water using conventional heating and microwave irradiation afforded high yields (71–92%) of 2,3-bis[(E)-2-aryl vinyl]-quinoxalines and 2,3-bis[(E)-2-arylvinyl]-pyrido(2,3-b)pyrazines. The photophysical properties of the resultant quinoxaline and pyrazine derivatives were studied; the pyridopyrazine derivatives were found to exhibit halochromism. 相似文献
60.
We report on an alternating current (AC) field induced organic electroluminescence (EL) device with internal charge carrier generation and recombination luminance of over 5000 cd m?2 under AC drive without charge carrier injection from external electrodes. The ultra-bright AC-EL is attributed to an optical optimization performed on the devices via numerical optical simulations based on an optical thin film model as well as an increase in the number of charge carriers achieved via the concept of molecular doping within the device. The luminance levels achieved are highest reported so far in literature for AC organic light emitting devices. 相似文献