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

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sensitivity, a liquid seismograph could be made to record re- sults in a very orderly and readable fashion. There is one fallacy in the experiments described above. The waves produced by movements inside the earth are dif- ferent from those produced by slight pressure on a table, the device used for producing small movements in the laboratory. If the results reported above are to be considered in evalu- ating the liquid seismograph, it must be assumed that the results would be similar using natural waves in place of movements produced artificially. The ultimate test of this new seismograplmic principle will be its ability to detect and identify actual earth movements, and actually, the principle will not be thoroughly tested until it is used for this purpose. The development and evaluation of the liquid seismo- graphic principle has just-begun. To date the only liquid tested has been water, and experiments will soon be run using liquids of varying viscosity. It is hoped that the mir- ror system can be improved upon, using knife-edge bearings and very lightweight material. Eventually, a complete seis- mograph will be built, completely enclosed in a lightproof box. A drum covered with photographic paper will be ro- tated by a synchronous motor, and will record the faint light beam reflected from the mirror apparatus immersed in the liquid. Hopefully, this seismograph will then be tested re- cording actual earth movements, with a standard seismo- graph acting as a control. Sultito Coordination Compounds STEVEN BINDER Niles Township H. S. North Sponsor - Mr. Frank Cardulla ABSTRACT Our understanding of sulfite ion chelation has changed rapidly in the last ten years. It had always been assumed that this ion could act as a bidentate ligand, bonding through two oxygen atoms. Recently, though, spectrophotometric data has suggested that the ligand actually forms a bridge between metal ions, using oxygen and sulfur. Two com- pounds which apparently have such a structure are di-JL - sulfitotetrakisethylenediaminedicobalt CIIIJ chloride and po- tassium di-J-L -hydroxo-J-A -sulfitodisulfitotetraaquodichro- mate CIIIJ. My paper discusses application of this and other recent developments to other sulfito coordination compounds. The several LMKSOXLJ3 complexes exhibit unusual sta- bility and insolubility. An excellent explanation for these properties would be a polynuclear structure. My paper dis- cusses various possible structures and how the true structure could be determined. I also reinterpret the isomerism of the ICIOCNHQASOQJ , using knowledge of the large trans- effect of the sulfito ion. The aminosulfito series is compared to the aminocarbonato series, wihose reactions are better known. Finally, the optical activity of all these compounds is discussed in detail. The Physiological Role of Stomata in Photosynthesis JAN LAURIDSEN Thornridge High School Dolton My project is primarily concerned with the function of stomata and exactly how they affect the leaf. A basic under- standing of their function was not difficult to achieve since a number of books have been written on this subject: butt in order to truly comprehend their relation to the entire leaf, af number of experiments were necessary. I selected the variable for may experiments by deter- mining whioh factors are directly related to stomatal ac- tivity. Of these factors involved, I chose temperature, hu- midity, and carbon dioxide. My first experiment, of course, was conducted under normal conditions, so that comparisons could be made later. My second experiment, however, involved temperature. I began by placing fourteen species of plants in total darkness for a period of two days. This step proved necessary in order to remove most of the starch from the leaves. I then placed the plants in an abnormal environment of 38' C. after coat- ing several leaves with petroleum jelly. The first leaf was coated on the upper epidermis, the second on the lower. The third leaf was coated on both epidermi, and the fourth was left uncoated. After a period of 1 day in a lighted area, the leaves were tested for starch. I noted that the amount of photosynthesis was greatly reduced under severe temperature change. I conducted several similar experiments with different variables. I used raised 'humidity by placing the plants in terraiums which had been previously filled with water. I also lowered the humidity by placing the plants in dessicators. My last experiment concerned carbon dioxide. Again I placed the plants in the terrariums, but this time I added a mixtLu'e of hydrochloric acid and 2.97 grams of Na,Cos, multiplying the normal concentration or carbon dioxide 1.03 per centl by a factor of five, which resulted in .15 per cent. As a result of my experiments, I have come to one basic conclusiong that all plants must be considered individually. Although general statements can be made concerning stoma- Eal behavior, biological variation remains the dominating orce. The Effects ot Spring Constant and Chassis Mass on the Average Amplitude ot Chassis Bounceis an Independent Rear Suspension System STEVEN CARHART Lyons Township High School LaGrange STATEMENT OF PURPOSE The purpose of this project is to find quantitative rela- tionships among the average amplitude of chassis motion at the rear of a one-eighth scale automobile encountering a series of obstructions, the mass supported by Uhe rear wheels, and the spring constant of the coil springs in the suspension. APPARATUS USED The somewhat unusual nature of the apparatus designed for this experiment makes a brief description of it before pro- ceeding desirable if not mandatory. The apparatus is of original design and consists of a onc- eighth scale automobile chassis mounted in such a way that the rear wheels rest on a rotating 'hollow metal drum on which obstructions of various sorts may be mounted across the path of one or both wheels. In experimentation, the ob- structions usually struck both wheels simultaneously rather than only one wheel to eliminate chassis torsion as a factor in determining the amplitude of dhassis bounce. The front of the chassis is supported by two pins stuck into the end chassis member from side supports: the chassis pivots about these two pins. The stationary front of the chassis may be considered to approximate a front suspension system which has encountered a bump soon to hit the rear, feacted to it, and brought the front of the chassis to equi- ibrium. 1

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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

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1 g5.sr. x PNG..- u.'.5 'M - JS.. U., 1 16.501 1 5 5 o U UI eu RSSB C5106 umm H o CNRS ' Mo X The magnitude bfwffhe deflection at the rear of the chassis when the wheels actually do strike the obstruction on the ro- tating drum is recorded by means of a spring aluminum pen arm attached to the rearmost chassis member. The pen arm is reinforced with wood except at the very end to reduce tor- sion caused by the friction of the pen on the recording paper. The writing instrument is a felt marker with a very fine point. It records on paper mounted on a rotating drum placed to the side of the chassis. lnqflah uasem N--' I 1 gqaflnca ..L'!' Gam QQ MOTU'- , - Posrpuu GNU r.oNs1ilvc1 9? fl-Grefkbws DY-Oh frfc-r g To QQCALQX The recording drum consists of a hollow sheet metal cyl- inder, open the bottom, which is fastened to a rotating shaft. The shaft is supported by a bearing and is driven through an 8:1 gear reduction from a small, low speed electric motor. The chassis itself is a simple perimeter type with cross bracing. It is constructed primarily of 56 square spruce strips glued and nailed together. The two wheels riding on the drum turn on two half-axles which are independently sprung, each pivoting about a pin slightly offset from the center of the chassis. Each half-axle is sprung by a coil spring and located fore-and-aft by wood strips forming a channel which limits axle motion to the vertical. wana str-WS X SPW5' Quoy SUSPGNSIDIJ frm 10 seated AX,-Q gent WWW Sine who In later experimentation, the rubber tired wheels which were used originally were replaced with metal wheels. The half-axles used with these new wheels were thinner than the old ones so the simple channel which had previously located the axles for-and-aft was no longer effective. The suspen- sion was therefore modified slightly with the introduction of control arms to locate the axles. These control arms pivoted with the axles about a point directly in front of the axle pivot. nv Wm svsveusmvl cemtut Aan Pm I MDIHI'-ICFTIUNS 1' get mee- no-r 10 stud ' mt Qwot- U game as HW?-6. Another modification which was made in later experi- ments was the addition of shock absorbers or more cor- rectly, dampers, consisting of strips of wood which introduced additional friction into the suspension by pressing against the axle. There were located on the outside of the wheels and pressed on that part of the axles which extended beyond the wheels themselves. The dampers were located by a yoke which ran across the width of the chassis. L., I ibut! TOY elw.vnS1?4Nv.:bvL vue-J 9 lv 5 HJ: R... 1 .Sa After a small tray of weights was added to the left side of the chassis to balance the pen arm on the right, a box-like carrier was mounted on the chassis into which weights could be taped to vary the mass of the chassis. A number of nearly identical lead weights were cast and numbered for identification. A light bar was passed through the axle channels and either end was placed on the pan of a balance at equal distances from the center of the chassis. The front of the chassis was supported, and the weights added in pairs in a standard order. The mass supported by each balance for increasing numbers of weights were as follows: Weight No.'s Mass on each balance none added 160 g. 1-2 191 1-4 221 1-6 251 1-8 280 1-10 311 1-12 342 1-14 372 Fourteen weights was the maximum load used in experimen- tation because greater numbers of weights placed dangerous strain on the apparatus as the chassis crossed the obstruc- tion. Since for a coil spring AQ Q K AF where K is some constant,A1.. is the change in length of spring, and A F is the force applied to the, spring, a single measurement of the compression caused by a known force will give the spring constant. The following apparatus was used to determine the values for K for springs used in the experiment: -1 mnovnw- 'LGU :muff WU? Masons 9 Mmpu. RT gawutvauw-5 wsmuasic -T-1...-- M555 gf,,,.,u. muowh' The springs which were tested in this manner were found to have spring constants of 3.78, 4.87, 6.38, 25.8, 36.8, and 110 newtons! centimeter. Springs which were shorter than the standard length of 3.00 cm. were lengthened with wood blocks glued onto one end, while the one that was longer than 3.00 cm was cut. 3.00 cm was chosen for the standard length because it gave the least camber variation from zero, i. e., slightly positive under light load and slightly negative under heavy load. Springs were mounted by passing a loop of adhesive tape through the last coils at either end of the spring. The tape in turn was passed around the chassis member directly above the axle just inside the wheel and also around the axle to hold the spring securely in place. 1596 TAPE -stew. M00 5Tl ' 'Q