Illinois Junior Academy of Science - Yearbook (Urbana, IL)

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Sawclust Effect On Tilth f LYN GRANDT , LaGrove High School I l Farina PURPOSE The purpose of my project was to observe the effects of sawdust and ammonium sulphate on the tilth of the soil under several normal conditions. PROCEDURE In working witnh my first set, I 'took thirty-five soil sam- ples from seven different locations. In each I put one table- spoon of sawdust and one-half teaspoon of ammonium sul- phate. In seven I planted corn: in seven, alsike clover. To one set, I added earthworms. In one set, I added neither plants nor earthworfns. All four sets were watered. For the control, a fifth set, unplanted and containing no earth- worrns, was left dry. In doing set two, I repeated the procedure followed in doing set one, but the following additions were made: seven cartons containing soil, sawdust, and ammonium sulphate were planted with corn and alsike clover. Earthworms were added to seven more cartons containing soil, sawdust, ammo- nium sulphateg corn and alsike clover were planted in these. To seven more cartons of untreated soil, I added gypsum. All additional groups received water. I ' RESULTS I received very good results on my first set. The earth- worms made the soil more porous for better tilth. There was much variation in the growth of the corn and alsike clover. Some of the soil became very tightly packed. The Study ot Mass Interchange in Binary Systems ROBERT McNAMARA Brother Rice High School Chicago Brother M. R. Kelleher In this study it was my aim to research mass interchange in binary star systems. My study, though, was not concerned with the actual observation of these systems, but of the forces that control the mass transfer process and how mass transfer affects the system. With this in mind, I limited myself to the fact that mass transfer exists and then I tried to determine under which conditions mass transfer can oc- cur, the reason for its occurrence, and how it effects the behavior of different star systems. The first consideration in the study of mass transfer is to define a surface to which the infinitismal particle of the star is to be restricted. This can be defined by the equation: X'-l-y'+ 2.1-1 -M- .2..M. rt + rl 2 C where the two masses are A defined and 1 -,Ll , respectively, and rotating axis having been chosen with the center of mass as the origin. The x axis is the line joining the two masses. Once C is stated the surface it defines is called the equipotential or zero-velocity surface. This surface divides space into two spaces, one accessible and the other inacces- sible to the infinitismal particle. The exact shape of this surface depends on the value of C. For large C the zero velocity surfaces differ only slightly from separate closed spheres. For decreasing C they become more elongated until they touch at some common point on the x axis, L.. For smaller C, a single zero velocity surface surrounds the two bodies, and for even smaller C, the dumb-bell increases in size and finally opens up at point L2 and finally Ls. Particles placed at these points are free of gravity and will remain at rest unless perturbed by external forces. L2 and L3 control the mass flow out of the system and Ll is the route for transfer. The equipotential surface or zero-velocity surfaces are the keys to the mass transfer process. In close binary sys- tems the lobes meet at a common point, L., along the x axis. In the systems with data leading to the fact of mass inter- change, it is speculated that the primary in the system be- gins to evolve and it starts to fill its equipotential lobe. This expansion is very rapid, because if the primary is to reach its Roche limit, it must go through the Hertzsprung gap. This rapid evolution quickly expands the radius of the pri- mary and the star fills its lobe. But, the tendency for ex- pansion remains, and the gases on the outer layers escape through the only possible outlet, L, As the mass flows into the lobe of the secondary, it takes up orbit around the sec- ondary and forms a shell or ring around the star. Some of the mass may escape the system at points La and Ls, but this depends on the value of C. Now we come to our first major difficulty. Spectro- scopic observations of the 70 or 80 close binary systems have found that in systems with mass transfer it is always the secondary and not the primary which has filled its lobe to the Roche limit and is transferring the mass to the other lobe of the system. This situation can be explained by the hypothesis of Donald C. Morton, which states that the pri- mary does evolve first, fills its surface, and transfers enough of its mass to its other companion so as to exchange the roles of primary and secondary. fThis does not include very close systems, i.e., W. Ursa Majoris.J Plotting of the Roche limits of typical systems on the H - R diagram shows tlhe primary can only reach its limit in the Hertzsprung gap, where even normal evolution is relatively fast. However, for this to be valid it must be accomplished in a process that its chances of being observed during the transmutation are small. This transition has been found to be fast enough so that few sys- tems could be caught making it. First, we start with a nearly homogenous primary in one of the various phases of evolution that is in a nuclear time scale. The nuclear time being stated for the star by the equation: rn L log T815 I 10.1 + log Fig -' log T19 If, during this interval, the star goes into a phase lasting a Kelvin Time, the Kelvin Time for the primary being de- fined by: m .Is log Tau I 7.7 + log me - log Lg K then we would expect to see less than 1111 of the group mak- ing the transmutation since the Kelvin Time is shorter by a factor of 200. Also, since the rate of transfer during the instability is governed mainly by the time it takes the outer layers to reach thermal equilibrium, the Kelvin Time may be somewhat shorter than for that of the whole star. Sta- bility returns in the expansion when t-he star loses so much mass as to approach homogenity with a Hydrogen poor com- position. But, this happens after the exchange of the role of primary and secondary. This accounts for about all observations except those of secondaries only partially filling their lobes, but this is more than likely due to a different composition, in which the sec- ondary lacks a Hydrogen rich envelope. It may be expected eventually that the new primary will start to evolve and return some of the mass that came from it originally. tStruve, 19443 CHoylel There has been much speculation as to how mass effects the evolution of a close binary system. An example would be Mr. Robert P. Kraft's suggested evolution of a W Ursa Majoris star to a U Geminorum star. These stars would not apply to Mr. Morton's theory due to their extreme closeness and their age. They seem to be older than the ordinary mass transferring binary or are in a later evolutionary phase. Mr. Kraft's whole theme rests on the findings of Huang t1956l that in a binary system, if a star loses mass to its 1 4

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The above students represented the IJAS at the AAAS meeting, where they presented their papers. Left to right: Larry Lunardl, Lynn Grandt, Sister Mary Alvernla.. -xv S. s mai gi-an N 'ms ft H5 : f - Pamela. Carsan Western High School, Macomb

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companion, its Period will decrease, and if it loses mass to space it will increase. In the table below is related some of the similarities of the two systems: Pnoranrv u cammoauwr w uns.-. Majoms lm 0. dzs e. '11 nt, tm, Q mtl llz Ill tm, + mp 1.5 - z.o. 1.2 - 2.5. Now if the W. Ursa Majoris fills its lobe and loses mass to both space and the other star, its evolution will be speeded up until it becomes a white dwarf. Later, the new primary begins its overflow of its lobe, giving the condition presently observed in U Geminorum variables. If the ejec- tion velocity of the component is small as compared with the relative velocity of the components and if efvo, we can wri e - 3 P - cm, + --.1. I cmn, 0 Imp + m,l rn, where . subscripts indicate initial values and P and s re- fer to the original primary and secondary by mass. Selective solutions have been tried and found to apply, but the equation only is valid when the ejection velocity eAJo. Observation of this point is not readily available. Also mass interchange seems to play an important part in the life of most novae. Findings now seem to point that all novae are binary, composed of a white dwarf and a sub- giant who is filling its lobe. It seems possible that the in- falling matter may be the cause of the outbursts, due to the white dwarf's composition. Whatever the reasons for the outbursts of the novae and dwarf novae, they must be related somehow to the mass transfer process. Now, through the integration of these facts my con- clusion is that mass transfer process is of major importance to the binary system. The full extent that mass transfer has on the binary system can be seen at a quick glance. The transfer process affects the mass ratio, the period, and the luminosity of the system. It also is a major factor in the evolution of the system and in some cases such as novae and dwarf novae, it seems to be a cause of outburst. ' BIBLIOGRAPHY Burbridge, Dr. Geoffery 8: Margret, Encyclopedia of Physics Hoyle, Fred, Frontiers of Astronomy Kraft, Robert P., Cataclysmlc Variables as Binary Stars Advances in Astronomy a.nd Astrophysics, Vol. II Kraft, Robert P., 1962 - Exploding Stars Scientific American - Vol. 206, No. 4 Kraft. Robert P. - U Geminorum Stars tDwarf Novael Astrophysical Journal - Vol. 135 Morton, Donald C. - 1960 - Evolutionary Mass Exchange in Binary Systems Astro. Journal - Vol. 132 Abt, Helmut A., The Frequency of Binaries Among Metallic Line Stars Astro. Journal - Vol. 133 Mumfort, George S., 1963 - Dwarf Novae II Sky 8: Telescope - XXIII Q33 su. .I Seismograph THOMAS J. Relrze INTRODUCTION Throughout history there have been many instruments designed for the purpose of detecting movements in the in- terior of the earth. Called seismographs, they range in de- sign and sensitivity from the ancient dragon wine jug of Choko to Benioff's sensitive electrical seismograph. The pur- pose of this paper is to introduce what is believed to be yet a new principle for the construction of the seismograph. The new idea involves the use of a liquid held in a con- tainer attached to the earth, the principle being that when the earth moves, the liquid is disturbed. A record of the disturbance is made by reflecting a light beam off the liquid and onto a photographic plate. MATERIALS AND PROCEDURE The first experiments were carried out using the sun as a. source of parallel light rays and a pan of water as the de- tection device. Later, a parallel beam generator was de- signed and constructed so that experimentation could be done at any time. Pans of water with different dimensions were subjected to minute movements tthe movements were produced by lightly touching the table on which the pan was anohoredl. The disturbances in the water were revealed by the reflection of a pencil of light off the water and onto a sheet of paper. A container with adjustable sides was then designed and built, and the effects of container shape were more systematically tested. In addition to rectangular pans, circular and horn-shaped containers were tested. Then, using one shape only trectangularl, the effects of changing the depth of the liquid were observed. In all these tests the light beam was reflected directly off the surface of the liquid, but tests were also made using a mirror on a free-moving bearing, attached to a paddle sub- merged in the liquid tthe mirror being steadied by a mag- netic fieldl. RESULTS Using rectangular containers, wave patterns like those in Figures 3a and 3b were created. As the ratio of length to width was increased, the waves parallel to the longer side became much stronger relative to the waves parallel to the short sides, resulting in less interference between the per- pendicular waves. By placing dampers along the short sides the waves produced there were reduced sufficiently so that only the longer waves were recorded by the light beam. The waves produced in circular containers were more random, and so much interference was present that the light beam merely diffused when the water was disturbed. The effect was similar when a horn-shape was tested. By reflecting the light beam off a mirror instead of the liquid surface, less sensitive but more orderly results were obtained. The disturbances in the liquid were translated into vertical movements only by the mirror apparatus, but the deviations of the light beam were not nearly as great using the mirror as reflecting the beam directly off the liquid surface. DISCUSSION AND CONCLUSIONS Of the container shapes tested, the best as far as obtain- ing orderly results seems to be rectangular, with one dimen- sion much greater than the other. In addition, dampers should be placed at the short ends. In testing a shape similar to Figure 3d, it was hoped that waves created in the wide end would be amplified by the narrowing sides, so that a light beam directed at the point x would record the amplified disturbances. Instead, waves created along the curved walls interfered with each other and made the results unreadable, the light beam diffusing off the liquid surface. If the depth of the liquid is too small, sensitivity is lost in the friction of the liquid on the container walls, but if the depth is too great, accuracy is lost because of currents in the liquid. The optimum depth would be a point between these two extremes, and it would vary for liquids of different vis- cosity. Even with the use of a narrow rectangular container the reflection of the light beam is not completely regularg that is. the movements of the reflection are not always vertical. This is one disadvantage for the use of a liquid in a seismo- graph, because random motion is inherent in liquids. If the light beam is to be recorded on a moving photographic plate, however, it is necessary that the movements of the beam be in one direction only. The mirror apparatus shown in Figure 2 solves this problem of random motion. The disturbances in the liquid appear on the reception plate as a series of vertical oscila- tions, similar to those produced by other types of seismo- graphs. The disadvantage of using a mirror as a reflector is that some of the sensitivity is lost in the conversion process. This fault might be largely overcome, however, if the mirror ap- paratus were made using more refined techniques, elimi- nating much of the weight and internal friction of the sys- tem. If a mirror system could be used with little loss in