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41.
Thomas Paul V. Mahadevan S. Kumar Krovvidi S. C. S. P. Goyal Sunil Murugesan S. Thirumurugesan R. Ezhilarasi T. Parameswaran P. Raju S. Saroja S. 《Journal of Failure Analysis and Prevention》2019,19(1):237-244
Journal of Failure Analysis and Prevention - A motorized bellow-sealed valve in the steam generator leak detection circuit of fast breeder test reactor developed sodium leak while carrying out... 相似文献
42.
Fatih Kalkan Sai Kranthi Vanga Ramesh Murugesan Valerie Orsat Vijaya Raghavan 《Drying Technology》2017,35(5):527-533
This study was performed to investigate the influence of air inlet temperature (AIT) on the microencapsulation of hazelnut oil by spray drying. Encapsulated powders were analyzed for moisture content, powder yield, surface oil, encapsulation efficiency (EE), bulk density, and particle morphology. The obtained results demonstrated that moisture content, surface oil, and bulk density decreased by 37.8, 27.5, and 33%, respectively as AIT increased from 140 to 220°C. However, powder yield and encapsulation efficiency increased considerably with the rise in AIT. Higher EEs of about 75–80% were observed in this study. 相似文献
43.
44.
The Impact of Sequential Fluorination of π‐Conjugated Polymers on Charge Generation in All‐Polymer Solar Cells 下载免费PDF全文
Kakaraparthi Kranthiraja Seonha Kim Changyeon Lee Kumarasamy Gunasekar Vijaya Gopalan Sree Bhoj Gautam Kenan Gundogdu Sung‐Ho Jin Bumjoon J. Kim 《Advanced functional materials》2017,27(29)
The performance of all‐polymer solar cells (all‐PSCs) is often limited by the poor exciton dissociation process. Here, the design of a series of polymer donors ( P1 – P3 ) with different numbers of fluorine atoms on their backbone is presented and the influence of fluorination on charge generation in all‐PSCs is investigated. Sequential fluorination of the polymer backbones increases the dipole moment difference between the ground and excited states (Δµge) from P1 (18.40 D) to P2 (25.11 D) and to P3 (28.47 D). The large Δµge of P3 leads to efficient exciton dissociation with greatly suppressed charge recombination in P3 ‐based all‐PSCs. Additionally, the fluorination lowers the highest occupied molecular orbital energy level of P3 and P2 , leading to higher open‐circuit voltage (VOC). The power conversion efficiency of the P3 ‐based all‐PSCs (6.42%) outperforms those of the P2 and P1 (5.00% and 2.65%)‐based devices. The reduced charge recombination and the enhanced polymer exciton lifetime in P3 ‐based all‐PSCs are confirmed by the measurements of light‐intensity dependent short‐circuit current density (JSC) and VOC, and time‐resolved photoluminescence. The results provide reciprocal understanding of the charge generation process associated with Δµge in all‐PSCs and suggest an effective strategy for designing π‐conjugated polymers for high performance all‐PSCs. 相似文献
45.
Venkatapathi M Hirleman ED 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(10):3366-3370
The scattered and internal fields of an infinite, homogeneous cylinder illuminated by a linearly polarized beam depend on the following parameters: the object size parameter of the cylinder (ka, where k=2pi/lambda, lambda is the wavelength of the incident beam in the surrounding medium, and a is the radius of cylinder), the complex relative refractive index of the object, the beam size parameters (komega(1) and komega(2), where omega(1), omega(2) are the representative beam dimensions), the angle between the cylinder axis and the Poynting vector of the incident wave, and the angle between the plane of polarization and the plane of incidence. Only when the dimensions of the beam are much greater than the cylinder diameter, and hence the portion of the beam interacting with the cylinder is essentially uniform, can the plane-wave solution be used in computing the scattered and internal fields. Hence a rigorous electromagnetic approach like the generalized Lorenz-Mie theory for spheres is used to study the effect of beam size parameters on the internal fields in an infinite cylinder irradiated by elliptical Gaussian beams. The significant effects of beam size parameters on the internal fields in an infinite cylinder are presented using specific cases of (1) resonance effects in a glass cylinder (ka=45.726, transverse-electric mode 53,3) and (2) a cylindrical microchannel (ka approximately 760) irradiated by a 632.8 nm laser beam. 相似文献
46.
P. Kalaichelvi T. Murugesan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,69(1):130-136
A generalized correlation for slip velocity in terms of fundamental variables (specifically excluding dispersed phase hold-up), using a large bank of published data along with those of the author is presented. A collection of 1412 experimental measurements (for 12 liquid–liquid systems from 13 different sources) representing slip velocity data over a wide range of variables is used for developing a new empirical correlation. The proposed correlations are more exact and simpler to use than the earlier correlations. In this present work, two regions of operations are also confirmed. © 1997 SCI. 相似文献
47.
N. Subha M. Mahalakshmi M. Myilsamy N. Lakshmana Reddy M.V. Shankar B. Neppolian V. Murugesan 《International Journal of Hydrogen Energy》2018,43(8):3905-3919
A novel photocatalyst comprises of ZrO2TiO2 immobilized on reduced graphene oxide (rGO) – a ternary heterojunction (ZrO2TiO2/rGO) was synthesized by using facile chemical method. The nanocomposite was prepared with a strategy to achieve better utilization of excitons for catalytic reactions by channelizing from metal oxide surfaces to rGO support. TEM and XRD analysis results revealed the heterojunction formed between ZrO2 and single crystalline anatase TiO2. The mesoporous structure of ZrO2TiO2 was confirmed using BET analysis. The red shift in absorption edge position of ZrO2TiO2/rGO photocatalyst was characterized by using diffuse reflectance UV–Visible spectra. ZrO2TiO2/rGO showed greater interfacial charge transfer efficiency than ZrO2TiO2, which was evidenced by well suppressed PL intensity and high photocurrent of ZrO2TiO2/rGO. The suitable band gap of 1.0 wt% ZrO2TiO2/rGO facilitated the utilization of solar light in a wide range by responding to the light of energy equal to as well as greater than 2.95 eV by the additional formation of excited high-energy electrons (HEEs). ZrO2TiO2/rGO showed the enhanced H2 production than TiO2/rGO, which revealed the role of ZrO2 for the effective charge separation at the heterojunction and the solar light response. The optimum loading of 1.0 wt% of ZrO2 and rGO on TiO2 showed the highest photocatalytic performance (7773 μmolh?1) for hydrogen (H2) production under direct solar light irradiation. 相似文献
48.
ABSTRACT This article describes a compact numerical algorithm based on the generalized differential quadrature (GDQ) method for the numerical analysis of natural convection in a differentially heated square cavity. The velocity–vorticity form of the Navier–Stokes equations and energy equation are used to represent the mass, momentum, and energy conservations of the fluid medium in the cavity. The GDQ form of the governing equations and the vorticity definition at the boundaries are solved by a coupled solution algorithm using a global matrix scheme for all the field variables. The vorticity values at the boundary are correctly imposed using the GDQ method, which approximates a given space derivative with higher-order accuracy compared to the existing schemes based on Taylor's series expansion. This has assured a divergence-free solution for the flow field by satisfying the continuity constraint, though the pressure term is not used directly in the present formulation. The proposed algorithm is validated for a lid-driven cavity flow for Reynolds number Re = 100, 400, and 1,000, and the predicted velocity profiles are in excellent agreement with the benchmark solutions. The algorithm is then used to compute the average Nusselt number and flow parameters for natural convection in a square cavity for Rayleigh number Ra = 103, 104, 105, and 106. These results are in better agreement with the benchmark solutions than the results obtained by other numerical schemes, which used much finer grids compared to the present scheme. 相似文献
49.
Rajavel Vijayakumar Murugesan Rajkumar Parthasarathi Sridhar Sethuraman Pitchumani 《Journal of Applied Electrochemistry》2012,42(5):319-324
The effect of the anode and cathode flow field depths on the performance of a single cell Direct methanol fuel cell (DMFC)
of 45 cm2 active area were experimentally investigated. Double serpentine flow fields (DSFFs) with varying channel depth namely, 0.2,
0.4, 0.6, 0.8, and 1 mm but with fixed channel and rib width each of 1 mm on both anode and cathode were designed, fabricated,
and tested. The experimental study involved measurement of pressure drops across anode and cathode flow field plates, polarization,
and carbon dioxide concentration measurements at various current densities. The mass transport at both anode and cathode were
found to increase with increase in pressure drop across the flow field on account of reduced channel depth from 1.0 to 0.4 mm
at all current densities. However, further decrease to a channel depth of 0.2 mm was found to be counter-productive with different
phenomena operating on either side viz., increased CO2 slug length on the anode flow channel and increased methanol crossover on the cathode side. Hence, the maximum performance
for DMFCs was observed for a channel depth of 0.4 mm on anode and cathode flow fields. A decrease in flow field channel depth
at cathode was found to increase the methanol crossover due to convective mass transfer effect. 相似文献
50.
M. Kumarasamy Raja Dingjuan Chua Yong Ping Xu 《Analog Integrated Circuits and Signal Processing》2012,70(1):57-67
An OOK transmitter in 433-MHz ISM band employing a speed-up circuit is described. The proposed speed-up circuit accelerates
the start-up of the oscillator and buffer by briefly increasing the bias currents during transmission of bit “1”. This leads
to a data rate increase from 3 to 10-Mb/s without any penalty on power consumption. The data rate can also be made adaptable
by varying the duration in which the bias current is increased. The proposed OOK transmitter is implemented in 0.35-μm CMOS
technology. The measured results show that the transmitter achieves a maximum data rate of 10-Mb/s with a dc power consumption
of 518 μW from a 1-V power supply, yielding an energy efficiency of 52 pJ/bit or 0.97 nJ/bit/mW when normalized to the output
power. This paper also derives a closed form equation which describes the transient behavior of Colpitts oscillator during
start up. 相似文献