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Some Effects Of Nitrogenous Fertilizers In The Nitrifying Power Of Carrington Loam, Mark H. Brown
Some Effects Of Nitrogenous Fertilizers In The Nitrifying Power Of Carrington Loam, Mark H. Brown
Proceedings of the Iowa Academy of Science
The World War stimulated research on the production of synthetic nitrogenous compounds and after the war, this activity was transferred to the production of synthetic nitrogenous fertilizers. Today these fertilizers are rapidly coming into practical use and a knowledge of their effects on soil conditions is essential to a proper determination of their agricultural value and economic significance.
Further Observations On The Behavior Of Vanillin Substitution Products: (A) The Perkin Reaction; (B) The Preparation Of Substituted Vanillic Acids, L. Chas. Raiford, Victor S. Webster, Dwight J.. Potter
Further Observations On The Behavior Of Vanillin Substitution Products: (A) The Perkin Reaction; (B) The Preparation Of Substituted Vanillic Acids, L. Chas. Raiford, Victor S. Webster, Dwight J.. Potter
Proceedings of the Iowa Academy of Science
When the carbonyl group is joined directly to carbon and hydrogen (aldehydic) or to carbon and carbon (ketonic) it reacts with phenylhydrazine to give the corresponding phenylhydrazone. When the radical is joined directly to nitrogen and hydrogen, as in formanilide, the products are aniline and formylphenylhydrazine. Substitution productions of formanilide behave similarly. If the radical is joined directly to nitrogen and nitrogen, as in diphenylurea, the products are aniline and a semicarbazide. The corresponding thiourea behaves similarly, and gives a thiosemicarbazide. If the reaction with the thioureas is carried out in the presence of a desulphurizing agent, guanidine derivatives are …
Organic Matter And The Life Of The Green Plant, Norman Ashwell Clark
Organic Matter And The Life Of The Green Plant, Norman Ashwell Clark
Proceedings of the Iowa Academy of Science
Along with the development of the conception of vitamins for animals there was introduced the corresponding idea of the necessity of unknown organic substances for plants. These accessory substances, termed auximones, were claimed to be essential for the growth and development of all chlorophyll producing plants. By the use of Lemna major it was found at Iowa State College that this claim was not valid, and that these plants would grow and reproduce successfully in a medium composed of highly purified inorganic salts. The presence of organic matter, however, stimulated the reproduction, and the effect of organic substances has been …
The Velocites Of Hydrolysis Of The Three Monomethoxy-Diphenyl Ketimines, James B. Culbertson, Amel L. Bresson
The Velocites Of Hydrolysis Of The Three Monomethoxy-Diphenyl Ketimines, James B. Culbertson, Amel L. Bresson
Proceedings of the Iowa Academy of Science
The 2- and the 3-methoxy-diphenyl ketimines have been prepared employing the general method of Moureu and Mignonac. The 4-methoxy-diphenyl ketimine had been prepared previously.
Reaction Of Some Carbonyl And Thiocarbonyl Compounds With Phenylhydrazine, L. Chas. Raiford, W. T. Daddow
Reaction Of Some Carbonyl And Thiocarbonyl Compounds With Phenylhydrazine, L. Chas. Raiford, W. T. Daddow
Proceedings of the Iowa Academy of Science
When the carbonyl group is joined directly to carbon and hydrogen (aldehydic) or to carbon and carbon (ketonic) it reacts with phenylhydrazine to give the corresponding phenylhydrazone. When the radical is joined directly to nitrogen and hydrogen, as in formanilide, the products are aniline and formylphenylhydrazine. Substitution productions of formanilide behave similarly. If the radical is joined directly to nitrogen and nitrogen, as in diphenylurea, the products are aniline and a semicarbazide. The corresponding thiourea behaves similarly, and gives a thiosemicarbazide. If the reaction with the thioureas is carried out in the presence of a desulphurizing agent, guanidine derivatives are …
Notes On Some Paleozoic Echinoderms, A. O. Thomas
Notes On Some Paleozoic Echinoderms, A. O. Thomas
Proceedings of the Iowa Academy of Science
The following notes are intended as a record of some fossil echinoderms recently added to the paleontological collections at the University. The first to be mentioned is a lot of five calyces belonging to a notable spiny-domed crinoid known as Batocrinus icosidactylus Casseday.
Nomenclature And Classification Of Geologic Formations With Special Reference To The Cretaceous Of Iowa, A. C. Tester
Nomenclature And Classification Of Geologic Formations With Special Reference To The Cretaceous Of Iowa, A. C. Tester
Proceedings of the Iowa Academy of Science
Confusion exists as to the proper use of the various terms designating the character of divisions of a rock sequence. The terms group and stage are often improperly used. Most writers follow the standard of the International Geological Congress, but the United States Geological Survey uses the terms in a different sense. The history of the various terms is reviewed in this paper; and the writer makes suggestions for a standard usage with special reference to their application to the Cretaceous rocks of Iowa.
Suggested Revisions Of Pleistocene Classification, George F. Kay
Suggested Revisions Of Pleistocene Classification, George F. Kay
Proceedings of the Iowa Academy of Science
Recently suggestions have been made by Leverett, Leighton, and by the writer with regard to the revision of the generally accepted classification of the Pleistocene or Glacial Period of the Mississippi Valley. Each of the proposals is discussed.
The Rock Shelters Of Allamakee County, Iowa, A Preliminary Survey, Ellison Orr
The Rock Shelters Of Allamakee County, Iowa, A Preliminary Survey, Ellison Orr
Proceedings of the Iowa Academy of Science
Among the rock formations of Allamakee county is one to which the geologists have given the name of Jordan Sandstone. This rock first begins to show above the Mississippi river at McGregor, Iowa. At Waukon Junction, nine miles above, there is a fine exposure from the station up to and above "The Painted Rock" showing its characteristic buttresses, caves, fissures and over-hanging ledges. At New Albin it has risen to more than two hundred feet above the river.
Geosynclinal Concept, Charles Keyes
Geosynclinal Concept, Charles Keyes
Proceedings of the Iowa Academy of Science
Repeated reference of late to the presence of geosynclines in Iowa directs attention to the fact that there appear to be really no such features displayed within the limits of our state. Erroneous use of the term is perhaps largely due to the original misleading composition of the word. It seems not to be realized, even in our text-books, that the feature to which Hall originally referred is an unusually thick body of sedimental accumulation, rather than a structure as many appear to think, or that Dana, who coins the sonorous title, converts the Hall concept into a structural affair …
The Stratigraphic Relations Of The Greenhorn And Niobrara Formations Of Western Iowa And Adjacent Areas, N. C. Georgesen
The Stratigraphic Relations Of The Greenhorn And Niobrara Formations Of Western Iowa And Adjacent Areas, N. C. Georgesen
Proceedings of the Iowa Academy of Science
The purpose of this paper is to show the stratigraphic relations of the Greenhorn and Niobrara formations from Sioux City, Iowa, northward along the Big Sioux River, and westward along the Missouri River. It is concluded that the Niobrara formation does not occur in Iowa, but that the chalky beds described by Bain, Calvin and others belong to the Greenhorn formation.
Resistivity Of Zinc Crystals, E. P. T. Tyndall, A. G. Hoyem
Resistivity Of Zinc Crystals, E. P. T. Tyndall, A. G. Hoyem
Proceedings of the Iowa Academy of Science
The resistivity at 20°C of zinc crystals made of Kahlbaum's purest and of "Spectroscopically Pure" zinc (from New. Jersey Zinc Company) is given as a function of direction of current flow relative to the orientation of the crystal lattice. For the Kahlbaum crystals the results are very much more consistent than have previously been obtained and point to a higher ratio of p11/p1 than that obtained by Bridgman. The "Spectroscopically Pure" crystals agree in the main with the Kahlbaum, but there are a few exceptional cases which tend to confirm Bridgman's strain theory. It seems more probable, however, that an …
Magnetic Properties Of Thin Nickel Films, H. E. Malmstrom
Magnetic Properties Of Thin Nickel Films, H. E. Malmstrom
Proceedings of the Iowa Academy of Science
Nickel films deposited from a nickel ammonium sulphate solution containing boric acid show decreasing coercive force with decreasing thickness in the range from 140 to 60 mμ. The films are similar to films deposited from the same solution but without boric acid, but are magnetically harder. Nickel films show an ageing effect not found for iron and cobalt. Heating to l00°C accelerates this effect. The effect of tension on the films is studied by measuring at 100°C, in which case the differential expansion of the brass base and the film supplies the tension. The effect is zero for thickness of …
The Iowan Gravels In Northeastern Iowa, Paul T. Miller
The Iowan Gravels In Northeastern Iowa, Paul T. Miller
Proceedings of the Iowa Academy of Science
The gravels related to the Iowan glaciation of northeastern Iowa have been studied in the field and laboratory. Three factors were significant in the field correlation, (a) stratigraphic relations (b) topographic position and (c) amount of weathering. In the laboratory the size, range, shapes, and lithology of the gravels were studied but little of value for correlation purposes was obtained.
A Concave Ultrasonic Diffraction Grating, George E. Thompson
A Concave Ultrasonic Diffraction Grating, George E. Thompson
Proceedings of the Iowa Academy of Science
A new concave ultrasonic diffraction grating has been constructed and used in the measurement of wave-lengths between one and three millimeters. An oscillating quartz crystal is used as generator and receiver of the sound waves. Results are compared with those obtained by the Pierce interferometer and found to agree.
On Atmospheric Electricity, C. S. Dorchester, L. W. Butler
On Atmospheric Electricity, C. S. Dorchester, L. W. Butler
Proceedings of the Iowa Academy of Science
An attempt was made during the summer of 1930 to check results claimed by Christofleau, Vincent, and others relating to the effect of atmospheric electricity on the growth of plants. The results were negative. During the course of these experiments, it was found that, except during the very driest part of the summer, the fair weather current was upward, a result which directly contradicts the work of other investigators in other parts of the world. No accurate comparison could be made with Simpson's value or the total currant between earth and air on account of the type of apparatus used.
Lens Effect Of Pressure Windows, Carl Benz, Thos. C. Poulter
Lens Effect Of Pressure Windows, Carl Benz, Thos. C. Poulter
Proceedings of the Iowa Academy of Science
The lens effect of pressure windows has been studied at pressures as high as 30,000 atmospheres. These lens effects are found to be due to four primary causes. 1st. Pseudo lens effect caused by temperature gradients in the material under pressure. 2nd. The bulging of the outside surface of the pressure windows. 3rd. The Pseudo lens effect due to unequal strains in the glass. 4th. The bulging of the inside surface of the window combined with the difference of index refraction of the material under pressure and the glass or quartz of the window. Methods for correcting for these lens …
The Velocity Of Ultra Waves In Ether Vapor, George E. Thompson
The Velocity Of Ultra Waves In Ether Vapor, George E. Thompson
Proceedings of the Iowa Academy of Science
The velocity of high frequency sound waves has been determined in ether vapor at several pressures. The velocity is slightly less at the higher pressures.
The Chemiluminescence Of Solid Sodium, R. M. Bowie
The Chemiluminescence Of Solid Sodium, R. M. Bowie
Proceedings of the Iowa Academy of Science
Since the time of Davy, it has been known that freshly cut surfaces of sodium, when viewed in the dark, give off a faint light. G. Rebaul, in 1910, stated that the effect was due to the formation of the hydroxide upon reacting with the moisture in the air. In this article a series of experiments to determine the nature of the chemical reaction which caused the luminescence are described. It was found that the light was accompanied by the liberation of hydrogen, but that its liberation was not always accompanied by luminescence. Reactions in which halides were formed produced …
Influence Of Reducing Credit For Absence Of Regularity Of Class Attendance In College, E. O. Finkenbinder
Influence Of Reducing Credit For Absence Of Regularity Of Class Attendance In College, E. O. Finkenbinder
Proceedings of the Iowa Academy of Science
In the summer of 1916 at Iowa State Teachers College the rule of the faculty that one-tenth of a point of credit should be deducted for each unexcused absence in any class became effective. For the three years preceding that time the median percentage of absence per term was 2.2 with a mean variation of.13; immediately after the rule went into effect the median percentage of absence was lowered to 1.45 ±.25, which is a reduction in amount of absence of about one-third.
The Effect Of Immediate Knowledge Of Results On Motivation, B. F. Zuehl
The Effect Of Immediate Knowledge Of Results On Motivation, B. F. Zuehl
Proceedings of the Iowa Academy of Science
A study of the effect of immediate knowledge of results on motivation in which two types of procedure were used. During a period of three months the traditional type of tests was used, this part of the study serving as a means of getting a general rating of quality of work which certain classes in college were likely to do under the traditional procedure.
The Use Of The Individual Parts Of The Aptitude Test For Predicting Success Of Students, Gertrude M. Cox
The Use Of The Individual Parts Of The Aptitude Test For Predicting Success Of Students, Gertrude M. Cox
Proceedings of the Iowa Academy of Science
The Iowa State College Aptitude Test is composed of seven parts or sub-tests. These sub-tests have been used in predicting the success of the students during their first quarter in college.
The Correlation Of Implicit And Explicit Behavior And The Presence Of Sex Differences In Learning Responses, Alvah R. Lauer
The Correlation Of Implicit And Explicit Behavior And The Presence Of Sex Differences In Learning Responses, Alvah R. Lauer
Proceedings of the Iowa Academy of Science
The argument for a general integrating factor in behavior has largely been discounted on the basis of measurements of explicit responses. In most cases such samplings of behavior are subject to influence of training, either directly or indirectly. A criticism of such conclusions is offered.
Remedial Measures In Pitch Intonation, Lawrence E. Eberly
Remedial Measures In Pitch Intonation, Lawrence E. Eberly
Proceedings of the Iowa Academy of Science
Attempts of teachers of voice and violin to improve the pitch intonation of their pupils have been exceedingly wasteful of time, due to the tendency of the ear to be either too inaccurate or too easily satisfied in the matter of small differences of pitch. The tonoscope, an instrument now available for use in the music studio, provides an immediate objective visual check on the accuracy of produced tones and further motivation for the improvement of pitch intonation.
A Criticism Of The Law Of Effect, Clellen L. Morgan
A Criticism Of The Law Of Effect, Clellen L. Morgan
Proceedings of the Iowa Academy of Science
The criticisms of the law of effect as an explanation of selection or "stamping in" of bonds are herein based upon two studies of the nature of learning. One experiment consists of a Chinese Puzzle, the other of a Mental Maze.
A New Scientific Musical Staff, Carl E. Seashore
A New Scientific Musical Staff, Carl E. Seashore
Proceedings of the Iowa Academy of Science
The psychological laboratory in the University of Iowa is conducting a number of studies in the psychology of music, laying scientific foundations for the theory and practice of the art. To make these scientific findings in the interpretation of vocal and instrumental music as actually rendered, it has been necessary to design a scientific type of musical score. This has been built as closely as possible in musical terminology but is so designed as to show in great detail how the notes are actually sung and played. For example, instead of indicating the note "C" by the usual musical notation, …
An Artistic "Pianogram", Laila Skinner
An Artistic "Pianogram", Laila Skinner
Proceedings of the Iowa Academy of Science
This paper consists of a discussion of factors in artistic piano playing, studied from photographs made while an artist plays.
The Hearing Of The Vocal Vibrato, Harold Seashore
The Hearing Of The Vocal Vibrato, Harold Seashore
Proceedings of the Iowa Academy of Science
Paralleling the extensive study of the artistic use of the vocal and instrumental vibrato is this study in the perception of the vocal vibrato. By using a synthetic tone-mixer, variations in pitch and intensity deviations, both as to rate and extent, were produced for the observers who responded by several methods - production, comparison and estimate. The data indicate that the observers, all of whom possess high musical discrimination for pitch and intensity, hear the deviations in pitch extent as about one-third the actual amount, that different rates of oscillation near the average of artistic usage, have little significant effect …
An Appraisal Of Psycho-Physical Capacities And Abilities Significant For Success In Art, Hildegard Dreps
An Appraisal Of Psycho-Physical Capacities And Abilities Significant For Success In Art, Hildegard Dreps
Proceedings of the Iowa Academy of Science
The nature of art talent has been a problem of considerable research in the last decade. A careful survey was made of all available data in regard to selecting tests which were best adapted for the appraisal of certain capacities and abilities that function in the various artistic performances and 18 tests were selected. These were given to 27 subjects divided into three groups: a superior artistic group, an average group of art students with very little training, and a group of non-art people. Each subject reported individually for the tests and the amount of time required from each was …
Relationship Of Chance, Or Consistency, To Rate And Extent Of The Vibrato, Melvin S. Hattwick
Relationship Of Chance, Or Consistency, To Rate And Extent Of The Vibrato, Melvin S. Hattwick
Proceedings of the Iowa Academy of Science
The purpose of this study was to ascertain the role of chance, or consistency, in determining the rate and extent of the vibrato. Five most promising voice students of the University School of Music were secured for the study. Each was asked to sing two renditions of "The Last Rose of Summer" the second rendition following the first within an interval of five minutes. Recording of data in permanent form was secured by means of the strobophotographic camera, which simultaneously records duration and pitch changes, or variations of tones, in the form of a graph, with duration forming the abscissae …