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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Solar-terrestrial relations

Hartz, Theodore Robert January 1957 (has links)
The inter-relation of phenomena on the sun and in the earth's ionosphere has been studied in order to establish a causal dependence which could result from travelling solar particles. In addition to examining a variety of data from a number of sources, an extensive R.F. noise recording program was undertaken to provide information on those regions of the solar and terrestrial atmospheres from which optical data were not available. The occasions on which there was an influx of such particles into the earth's ionosphere were established from magnetic data, from optical observations of the Polar Aurora, and from H.F. and V.H.F. radio observations close to the Auroral Zone. On the basis of these data the ionospheric disturbances for a 12 month period were related to prior distinctive solar events that were considered capable of producing the high energy particles. The selection was made from the optical, spectroscopic and radio data available. It was found that solar flares, eruptive prominences, and disappearing filaments were the most frequent sources of Earth-reaching particles, and that large sunspots contributed only occasionally to ionospheric disturbances. Moreover, the radio noise data permitted a fairly reliable estimate of the particle velocities in the solar corona, which could be used to predict the probability of subsequent terrestrial effects of the ejected particles. A correlation coefficient of +0.65 was found between probabilities predicted from the solar information and observed ionospheric disturbances which occurred two or three days later. The observational evidence on the solar noise bursts and on ionospheric storms could only be explained on the basis of a considerable distribution of velocities for the particles ejected from the sun. It was shown that a Maxwellian distribution of corpuscular velocities was a probable one. Moreover, the observations indicated that particles are frequently emitted from the sun with a distribution of velocities, but that only in the case of very large phenomena are there sufficient particles with the high energies necessary to overcome the sun's gravitational field and reach the earth. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
122

A Study of the 21-cm line in the solar neighborhood

Venugopal, Virinchipuram R. January 1969 (has links)
A survey of 21-cm line emission at points equally spaced over the entire sky visible from Penticton, British Columbia, has been made, and the profiles obtained at the intermediate galactic latitudes have been used to determine several of the properties of the distribution of the gas in the solar neighbourhood and to study the dynamics of the gas including the determination of solar motion with respect to gas, the distribution of random velocities and the departure of gas velocities from circular motion. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
123

Analysis and fabrication of MIS solar cells with majority carrier conduction characteristics

Au, Ho Piu January 1978 (has links)
A simple model for a MIS solar cell incorporating the effects of inversion layer charge and non-uniform surface state charge has been generated. The inclusion of these terms in the analysis results in theoretical In I-V characteristics which, under forward bias in the dark, have a two slope nature very similar to that of practical MIS solar cells that have been reported to be operating in a minority carrier conduction mode. As the present model considers solely majority carrier conduction, an alternative explanation of the operation of these devices can be proposed. Experimental data were obtained from Al/SiO[sub x]/pSi solar cells and good agreement with the proposed theory was obtained. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Unknown
124

Comparison of algorithms for determination of solar wind regimes

Neugebauer, Marcia, Reisenfeld, Daniel, Richardson, Ian G. 09 1900 (has links)
This study compares the designation of different solar wind flow regimes (transient, coronal hole, and streamer belt) according to two algorithms derived from observations by the Solar Wind Ion Composition Spectrometer, the Solar Wind Electron Proton Alpha Monitor, and the Magnetometer on the ACE spacecraft, with a similar regime determination performed on board the Genesis spacecraft. The comparison is made for the interval from late 2001 to early 2004 when Genesis was collecting solar wind ions for return to Earth. The agreement between hourly regime assignments from any pair of algorithms was less than two thirds, while the simultaneous agreement between all three algorithms was only 49%. When the results of the algorithms were compared to a catalog of interplanetary coronal mass ejection events, it was found that almost all the events in the catalog were confirmed by the spacecraft algorithms. On the other hand, many short transient events, lasting 1 to 13h, that were unanimously selected as transient like by the algorithms, were not included in the catalog.
125

Effects of the Edges of 2D Materials on Photoelectrochemical Solar Energy Conversion

Yan, Tao 17 May 2020 (has links)
Research on renewable energy must be hastened to solve the energy crisis we are now facing. Among all sustainable energy sources, solar energy and hydrogen gas fuel are two of the most clean and powerful. Photo-electrochemical (PEC) reactions use solar energy to electrochemically split water to produce hydrogen gas. Photoelectrocatalyst materials play an important role in increasing the e ciency of PEC reactions by absorbing solar energy and directing the energy towards the desired electrochemical reactions. Two-dimensional (2D) layered materials including MoS2, WS2, and SnS2 have drawn considerable attention as electrocatalysts and photo-electrocatalysts because of the catalytically-active nature of their edges and high charge mobility and transport e ciency within their layers. This work focuses on the synthesis, measurement, and simulation of PEC properties and behavior of WS2 nanotubes and SnS2 nano akes. The rst part of this work focuses on experimental synthesis and PEC measurement of edge-on oriented WS2 nanotubes and theoretical simulation of the atomic con guration and electronic structure of the edges by density functional theory (DFT) . WS2 nanotubes were synthesized by chemical vapor deposition (CVD) and sulfurization, but showed very poor photresponse. The DFT simulation shows the edges of the WS2 nanotubes are metallic, like those of 2H-MoS2. The metallic edges likely act as recombination sites for photogenerated charges, which explains the poor photoresponse of WS2. The second part of this work focuses on experimental synthesis and PEC measurement of edge-on oriented SnS2 nano akes and theoretical simulation by DFT. The edge-on oriented SnS2 nano akes exhibited high photoresponse and excellent PEC performance. The DFT simulation determined the atomic con gurations of SnS2 edges, and the stability of both bulk-like and monolayer SnS2 edges at various S potentials. In contrast to WS2 and MoS2, the DFT simulation also determined that the edges of SnS2 are semiconducting, not metallic. Therefore, the edges of SnS2 would not cause recombination of photoexcited charges, and would enable SnS2 to achieve a high photoresponse, as was experimentally observed. The DFT results also showed that the band gap energy of the SnS2 edges becomes smaller with increasing sulfur coverage, and allowed the in uence of chemical synthesis conditions on the electronic structure of the edges to be determined.
126

Theoretical analysis of a variable aperture solar tower receiver

Galal, Tarek. January 1982 (has links)
No description available.
127

Predictive analyses for the temperature development and performance of solar ponds

Chepurniy, N. January 1976 (has links)
No description available.
128

The Study of a Double-Effect Basin Type Solar Still

Lantagne, Michel 06 1900 (has links)
Note:
129

Nocturnal production of solar still.

Tran, Van-Vi January 1970 (has links)
No description available.
130

Solar energy in the housing sector.

Strong, Pritchard L. 01 January 1973 (has links) (PDF)
No description available.

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