Diurnal and environmental characterization of solar photovoltaic panels using a PC-AT add on plug in card

This article describes the development of an instrumentation system for characterizing photovoltaic panels. It uses an add on card (which contains DAC, ADC and digital input/output ports) in conjunction with a PC-AT. The panels in a field are selected in succession through a set of relays actuated by the digital output port. The selected panel is loaded in discreet steps by a transistor loading circuit which is activated by the digital to analog convertor to trace the most significant portion of the I-V curve. The data shows that the power output is invariably lower than that specified by the manufacturer. The reasons for drop in output have been analyzed. It is shown that these effects can be represented by the curvature of I-V characteristic at the maximum power point (OP). The loss of power due to accumulation of dust and the increase in temperature of the panels can be significant.     

On the lower bounds of the second order nonlinearities of some Boolean functions

The rth order nonlinearity of a Boolean function is an important cryptographic criterion in analyzing the security of stream as well as block ciphers. It is also important in coding theory as it is related to the covering radius of the Reed-Muller code R(r,n). In this paper we deduce the lower bounds of the second order nonlinearities of the following two types of Boolean functions:

1.

with d=2^2r+2^r+1 and , where n=6r.

2.

, where x,y∈F_2^t,n=2t,n?6 and i is an integer such that 1?i<t,gcd(2^t-1,2ⁱ+1)=1.

For some λ, the functions of the first type are bent functions, whereas Boolean functions of the second type are all bent functions, i.e., they possess the maximum first order nonlinearity. It is demonstrated that in some cases our bounds are better than the previously obtained bounds.     

Differential regulation of redox proteins and chaperones in HbEβ-thalassemia erythrocyte proteome

Purpose: In (hemoglobin, Hb) HbEβ‐thalassemia, HbE (β‐26 Glu→Lys) interacts with β‐thalassemia to produce clinical manifestation of varying severity. This is the first proteomic effort to study changes in protein levels of erythrocytes isolated from HbEβ‐thalassemic patients compared to normal. Experimental design: We have used 2‐DE and MALDI‐MS/MS‐based techniques to investigate the differential proteome profiling of membrane and Hb‐depleted fraction of cytosolic proteins of erythrocytes isolated from the peripheral blood samples of HbEβ‐thalassemia patients and normal volunteers. Results: Our study showed that redox regulators such as peroxiredoxin 2, Cu‐Zn superoxide dismutase and thioredoxin and chaperones such as α‐hemoglobin stabilizing protein and HSP‐70 were upregulated in HbEβ‐thalassemia. We have also observed larger amounts of membrane associated globin chains and indications of disruption of spectrin‐based junctional complex in the membrane skeleton of HbEβ‐thalassemic erythrocytes upon detection of low molecular weight fragments of β‐spectrin and decrease in β‐actin and dematin content. Conclusion and clinical relevance: We have observed interesting changes in the proteomic levels of redox regulators and chaperons in the thalassemic hemolysates and have observed strong correlation or association of the extent of such proteomic changes with HbE levels. This could be important in understanding the role of HbE in disease progression and pathophysiology.     

Ultrathin Highly Luminescent Two‐Monolayer Colloidal CdSe Nanoplatelets

Surface effects in atomically flat colloidal CdSe nanoplatelets (NLPs) are significantly and increasingly important with their thickness being reduced to subnanometer level, generating strong surface related deep trap photoluminescence emission alongside the bandedge emission. Herein, colloidal synthesis of highly luminescent two‐monolayer (2ML) CdSe NPLs and a systematic investigation of carrier dynamics in these NPLs exhibiting broad photoluminescence emission covering the visible region with quantum yields reaching 90% in solution and 85% in a polymer matrix is shown. The astonishingly efficient Stokes‐shifted broadband photoluminescence (PL) emission with a lifetime of ≈100 ns and the extremely short PL lifetime of around 0.16 ns at the bandedge signify the participation of radiative midgap surface centers in the recombination process associated with the underpassivated Se sites. Also, a proof‐of‐concept hybrid LED employing 2ML CdSe NPLs is developed as color converters, which exhibits luminous efficacy reaching 300 lm W_opt^?1. The intrinsic absorption of the 2ML CdSe NPLs (≈2.15 × 10⁶ cm^?1) reported in this study is significantly larger than that of CdSe quantum dots (≈2.8 × 10⁵ cm^?1) at their first exciton signifying the presence of giant oscillator strength and hence making them favorable candidates for next‐generation light‐emitting and light‐harvesting applications.     

DNS study of pulsed film cooling for enhanced cooling effectiveness

Direct Numerical Simulation (DNS) of a pulsed film-cooling jet is presented to examine if pulsations of the coolant jet can enhance film-cooling effectiveness. Calculations are performed for a cylindrical jet inclined at 30°. The jet pulsation is defined by the duty cycle (DC) and the Strouhal number (St), both of which are varied in this study. Baseline calculations are done for a steady blowing ratio of 1.5. Both frequency and duty cycle are observed to influence the cooling effectiveness. For a peak blowing ratio (M) of 1.5, pulsing with a St = 0.32 and DC = 0.5 is shown to reduce jet blow-off and improve centerline and spanwise-averaged effectiveness over the steady M = 1.5 case.     

Direct Numerical Simulation of pulsed jets-in-crossflow

Direct Numerical Simulations of a jet with a passive scalar injected vertically into a crossflow (velocity ratio = 6) is performed at a jet Reynolds number of 5000. The role of sinusoidal forcing of the jet on the dynamics of the flow structures, and on the jet trajectory and jet spreading is examined. Sinusoidal excitations selected are at non-dimensional frequencies of 0.2, 0.4, and 0.6. For the unforced jet, shear-layer vortices on the leading edge of the jet have a preferred mode frequency of around 0.35. With forcing, the dominant frequency in the near field of the jet is the forcing frequency, but further downstream, vortex interactions/mergings lead to the growth of the subharmonic modes. For a forcing frequency of 0.2, the jet bifurcates in the vertical plane; at a forcing frequency of 0.4, the jet trifurcates into three jet-streams in the vertical plane; and, at a forcing frequency of 0.6, the jet bifurcates in the horizontal plane. The largest vertical penetration is at a forcing frequency of 0.4, while the largest horizontal spreading occurs at a non-dimensional forcing frequency of 0.6. Wake vortices, with a U-loop structure, are seen for all cases except at a forcing frequency of 0.6, where they are completely suppressed. The U-loop structure is asymmetric for the unforced and 0.2 forcing frequency case, and is consistent with the earlier experimental observations for unpulsed jets-in-crossflow. Through particle visualizations, a mechanism for the development of the wake vortices is presented in the paper. Mean statistics on isosurface contours are also presented, and asymmetry in the mean counter-rotating kidney pair vortex structures are also seen for the unforced and 0.2 forcing cases. The results of this study indicate the potential of using external forcing as a potential control strategy for controlling the jet penetration and mixing with the crossflow in either the vertical plane or the horizontal plane.     

Carbon nanohorn‐graphene nanoplate hybrid: An excellent electrode material for supercapacitor application

This study describes the capacitor behavior of carbon nanohorn (CNH)/graphene nanoplate (GNP) hybrid (CNGN). The well‐CNH‐decorated GNP‐plate electrode materials show high capacitance value (≈677 F/g) and can be extensively used in new generation for energy storage. In the hybrid (CNGN), two nanofillers jointly affect the capacitance behavior and increase the capacitance value of the CNGN hybrid. Homogeneous coating of CNH over the GNP plate plays an effective role to enhance the capacitance behavior of the composite. Field emission scanning electron microscopy and high‐resolution transmission electron microscopy analysis of the composite confirmed the CNH coating on the GNP plate. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42118.     

Peanut proteins: Applications,ailments and possible remediation

Peanut is an annually grown plant and the chiefly cultivated species is Arachis hypogaea L. Mainly three types of proteins, arachin, conarachin I and conarachin II are present in peanut. It is an important and cheap source of protein. It can also cause allergic reactions in human beings. The peanut protein contains two components, Ara h 1 and Ara h 2 which are mainly responsible to cause allergy. Different remedial measures have been proposed to fight with the allergenic property of peanut proteins such as treatment with peroxidase, phytic acid, active charcoal, and various enzymes to minimize allergenic effect. Improper storage of peanuts causes growth of a fungal organism that releases aflatoxin, which is a carcinogen to mammals. Use of aluminosilicate clay, gamma irradiation, ozonation methods have been discussed for aflatoxin decontaminated from peanut. In this critical review, we have given an overview of the different extraction procedures of the peanut proteins and pointed out the methodologies to minimize allergenic actions and detoxification of the aflatoxin contamination in peanut.