Co- and counter-helicity interaction between two adjacent laboratory prominences

The interaction between two side-by-side solar prominence-like plasmas has been studied using a four-electrode magnetized plasma source that can impose a wide variety of surface boundary conditions. When the source is arranged to create two prominences with the same helicity (co-helicity), it is observed that helicity transfer from one prominence to the other causes the receiving prominence to erupt sooner and faster than the transmitting prominence. When the source is arranged to create two prominences with opposite helicity (counter-helicity), it is observed that upon merging, prominences wrap around each other to form closely spaced, writhing turns of plasma. This is followed by appearance of a distinct bright region in the middle and order of magnitude higher emission of soft x rays. The four-electrode device has also been used to change the angle of the neutral line and so form more pronounced S-shapes

Laboratory simulations of astrophysical jets and solar coronal loops: new results

An experimental program underway at Caltech has produced plasmas where the shape is neither fixed by the vacuum chamber nor fixed by an external coil set, but instead is determined by self-organization. The plasma dynamics is highly reproducible and so can be studied in considerable detail even though the morphology of the plasma is both complex and time-dependent. A surprising result has been the observation that self-collimating MHD-driven plasma jets are ubiquitous and play a fundamental role in the self-organization. The jets can be considered lab-scale simulations of astrophysical jets and in addition are intimately related to solar coronal loops. The jets are driven by the combination of the axial component of the J×B force and the axial pressure gradient resulting from the non-uniform pinch force associated with the flared axial current density. Behavior is consistent with a model showing that collimation results from axial non-uniformity of the jet velocity. In particular, flow stagnation in the jet frame compresses frozen-in azimuthal magnetic flux, squeezes together toroidal magnetic field lines, thereby amplifying the embedded toroidal magnetic field, enhancing the pinch force, and hence causing collimation of the jet

Synthesis, Spectral and Antibacterial Studies of Binuclear Titanium(IV) / Zirconium(IV) Complexes of Piperazine Dithiosemicarbazones

The reactions of mono(cyclopentadienyl)titanium(IV) trichloride and bis(cyclopentadienyl)titanium(IV)/ zirconium(IV) dichloride with a new class of dithiosemicarbazone, derived by condensing piperazine dithiosemicarbazide with benzaldehyde (L1H2), 2-chlorobenzaldehyde (L2H2), 4-nitrobenzaldehyde (L3H2) or salicylaldehyde (L4H4) have been studied and different types of binuclear products, viz. [{CpTiCl2}2L], [{Cp2MCl}2L], ((L=L1, L2 or L3), [{CpTiCI}2L4] and [{Cp2M}2L4] (M=Yi or Zr), have been isolated. Tentative structures are proposed for these complexes based upon elemental analyses, electrical conductance, magnetic moment and spectral (electronic, IR, 1H and 13C NMR) data. Attempts have been made to establish a correlation between antibacterial activity and the structures of the products

Ionophoretic Technique for the Determination of Stability Constants of Mixed Complexes (M-Nitrilotriacetate-5-Amino Pentanoate Systems)

A new method, involving the use of paper electrophoresis is described for the study of the equilibria in mixed ligand complex systems in solution. This technique is based on the movement of a spot of metal ion under an electric field with the complexants added in the background electrolyte at p\u27H = 8.5. Concentration of the primary ligand (NTA) was kept constant while that of the secondary ligand (5-amino pentanoic acid) was varied. The plots of-log [5-amino pentanoic acid] against mobility were used to obtain information on the forma tion of mixed complex and to calculate its stability constants. The binary equilibria M(II)-(5- amino pentanoic acid) and M(II)-NTA have also been studied since this is a prerequisite for the investigation of mixed complexes. The stability constants of the cornplexes, metal-nitrilotriacetate- 5-amino pentanoate have been found to be 5.85, 5.50, 5.22, 3.96 and 3.90 (log K values) for Cu(II), UOz(II), Ni(II), Co(II) and Zn(II) complexes, respectively, at fL = 0.1 mol/L and a temperature of 35 -c

An artificial neural network model for rainfall forecasting in Bangkok, Thailand

This paper presents a new approach using an Artificial Neural Network technique to improve rainfall forecast performance. A real world case study was set up in Bangkok; 4 years of hourly data from 75 rain gauge stations in the area were used to develop the ANN model. The developed ANN model is being applied for real time rainfall forecasting and flood management in Bangkok, Thailand. Aimed at providing forecasts in a near real time schedule, different network types were tested with different kinds of input information. Preliminary tests showed that a generalized feedforward ANN model using hyperbolic tangent transfer function achieved the best generalization of rainfall. Especially, the use of a combination of meteorological parameters (relative humidity, air pressure, wet bulb temperature and cloudiness), the rainfall at the point of forecasting and rainfall at the surrounding stations, as an input data, advanced ANN model to apply with continuous data containing rainy and non-rainy period, allowed model to issue forecast at any moment. Additionally, forecasts by ANN model were compared to the convenient approach namely simple persistent method. Results show that ANN forecasts have superiority over the ones obtained by the persistent model. Rainfall forecasts for Bangkok from 1 to 3 h ahead were highly satisfactory. Sensitivity analysis indicated that the most important input parameter besides rainfall itself is the wet bulb temperature in forecasting rainfall

Performance Evaluation of PV Panel Under Dusty Condition

The performance of PV panel depends on the incoming sunlight on its surface. The accumulated airborne dust particles on panel surface creates a barrier in the path of sunlight and panel surface, which significantly reduces the amount of solar radiation falling on the panel surface. The present study shows a significant reduction in short circuit current and power output of PV panel due to dust deposition on its surface, whereas the reduction in open circuit voltage is not much prominent. This study has been carried in the field as well as in the laboratory. The reduction in maximum power output of PV panel for both the studies ensures a linear relation with the dust deposition on its surface. In the field study, the reduction in the power output due to 12.86gm of dust deposition on the panel surface was 43.18%, whereas in the laboratory study it was 44.75% due to 11gm of dust depositionArticle History: Received July 10th 2017; Received in revised form Sept 15th 2017x; Accepted 1st Oct 2017; Available onlineHow to Cite This Article: Tripathi, A.K., Aruna, M. and Murthy, Ch.,S.N. (2017). Performance Evaluation of PV Panel Under Dusty Condition. International Journal of Renewable Energy Develeopment, 6(3), 225-233.https://doi.org/10.14710/ijred.6.3.225-23