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Modification Of The Directive Influence Of Substituents In Certain Benzene Derivatives, L. Chas. Raiford, M. F. Ravely Jan 1937

Modification Of The Directive Influence Of Substituents In Certain Benzene Derivatives, L. Chas. Raiford, M. F. Ravely

Proceedings of the Iowa Academy of Science

Bromination of vanillin, 3-methoxy-4-hydroxybenzaldehyde, gives a yield of 88-90 per cent of the 5-bromo compound which indicates that the chief directive influence is exerted by hydroxyl. If the hydroxyl radical is first acylated and the resulting acetyl or benzoyl vanillin is brominated, an equally high yield of the 6-bromo derivative is obtained, and no other product can be isolated. Vanillic acid and methyl vanillate likewise give good yields of the corresponding 5-bromo compounds, while the acylated derivatives give the 6-bromo substitution products only. These results indicate that acylation of hydroxyl suppresses its orienting effect and the entrance of bromine into …

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Nitration Of The Tribromo Substitution Product Of Sym-Xylenol, L. Chas. Raiford, Donald W. Kaiser Jan 1937

Nitration Of The Tribromo Substitution Product Of Sym-Xylenol, L. Chas. Raiford, Donald W. Kaiser

Proceedings of the Iowa Academy of Science

In previous work Raiford and Miller1 showed that when a phenol or cresol containing bromine in both ortho and para positions is treated with nitrous acid, a halogen atom may be replaced by the nitro radical and isomeric mononitro compounds may be formed. Chlorine cannot be replaced in this way.

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Plant Microfossils Of An Iowa Coal Deposit, L. R, Wilson, A. L. Brokaw Jan 1937

Plant Microfossils Of An Iowa Coal Deposit, L. R, Wilson, A. L. Brokaw

Proceedings of the Iowa Academy of Science

Much work has been done with the microfossils of Quaternary peat and silt deposits in Europe and North America, but comparatively little has been done with plant microfossils in older carbonaceous deposits, and, as far as the authors are aware, no statistical study has been made of these in coal deposits. The present study was undertaken in an effort to test in the Iowa coal the statistical methods used by paleoecologists upon Quaternary peat deposits.

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Dakota Sandstone As A Basinal Basilium, Charles R. Keyes Jan 1937

Dakota Sandstone As A Basinal Basilium, Charles R. Keyes

Proceedings of the Iowa Academy of Science

Meek and Hayden's type-section of the Cretaceous Dakota sandstone is directly across the Missouri River from Sergeant Bluff, below Sioux City. Neither this outcrop, nor the fine exposure at Sergeant Bluff, which latter is commonly considered as Iowa's best section of the formation, are complete to top or to bottom. Drill-core records have shown the Dakota sandstone to extend nearly 200 feet below the base of the exposed section named; and erosion has removed perhaps as many more feet from the top.

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Original Great Magnitude Of Our Coal Measures, Charles R. Keyes Jan 1937

Original Great Magnitude Of Our Coal Measures, Charles R. Keyes

Proceedings of the Iowa Academy of Science

Recent diastatic analyses of our Des Moines coal measures, particularly of the great Arkansan centrum, or delta, of which the Iowa coal measures are a part, after the paradigm of the Cordilleran Cretacic geosyncline, indicate that only a relatively small proportion of the original deposition of coal-bearing beds now remain to us. Present thickness of the Iowa coal measures is perhaps 300 to 400 feet. In the beginning, the volume appears to have been more than four miles thick. The vast missing bulk was removed through erosion, mainly regional planation before the great Missourian series of limestones was laid down.

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The Plantersville Meteorite, Grimes County, Texas, John T. Lonsdale Jan 1937

The Plantersville Meteorite, Grimes County, Texas, John T. Lonsdale

Proceedings of the Iowa Academy of Science

The Plantersville meteorite fell on the afternoon of September 4, 1930, at a point three and one-half miles southwest of Plantersville, Grimes County, Texas. The locality of the fall is forested but several men were working nearby and recovered the specimen within a few minutes of its fall. The phenomena of fall included rumbling explosions and a noise like an airplane in flight. This find is a light-gray friable aerolite, weighing 2084.9 grams, with a dense black crust showing oriented thread lines. The shape is sub-conoid faceted with a well-developed brutseit. The dimensions are 5¾” X 4" X 3¾” measured …

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The Decomposition Of 4(Xp-1)/(X-1). Ii, Cornelius Gouwens Jan 1937

The Decomposition Of 4(Xp-1)/(X-1). Ii, Cornelius Gouwens

Proceedings of the Iowa Academy of Science

If 4X = 4(xp - 1) / (x - 1) where p is an odd prime then 4X= Y2 - (- 1) p-1 / 2 pZ2, Y and Z being polynomials in x with integral coefficients. These decompositions for 100< p< 200 were given by the author in the Proceedings of the Iowa Academy of Science, 43: 255-262. This work has now been extended to values of p< 225. The decompositions are given herewith. For all decompositions Y is a polynomial of degree (p - 1) / 2 and Z a polynomial of degree (p- 3) / 2. The coefficients only are given in each case first for Y, then for Z.

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Growth Conditions For Zinc Crystals, J. S. Kellough Jan 1937

Growth Conditions For Zinc Crystals, J. S. Kellough

Proceedings of the Iowa Academy of Science

Previous work by Schilling1 showed that additions of Cadmium were necessary to produce conditions favorable to growth of single crystals. The present work has to do with the effect of other impurities on growth conditions. At present it has been found, by using zinc with somewhat less iron impurity than Schilling's zinc but with the same addition of Cadmium, that the region favorable to growth is more like the original one of Hoyem and Tyndall and considerably different from Schilling's region.

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Hysteresis In Zinc Crystals, E. P. T. Tyndall Jan 1937

Hysteresis In Zinc Crystals, E. P. T. Tyndall

Proceedings of the Iowa Academy of Science

Hanson found that crystals under bending stress showed a small amount of "elastic hysteresis." It appears now that this hysteresis is characteristic of the apparatus used by Hanson, since a slight modification abolishes this hysteresis.

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Current Views With Reference To The Nature Of Liquid Structure, G. W. Stewart Jan 1937

Current Views With Reference To The Nature Of Liquid Structure, G. W. Stewart

Proceedings of the Iowa Academy of Science

This is a report of progress in the study of the structure of liquids, analogous to the crystal structure of solids. Prins has given a mathematical treatment wherein the crystal structure is approximated to an expressed degree of probability. Bernal has made this treatment more general. These efforts advance the subject by giving models capable of mathematical description. Experiments in Raman effect continue to show that the intermolecular forces in the liquid are much like those in the crystal solid. The study of glasses shows their crystallite structure and emphasizes the difference between glass and liquid. These results, as others, …

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Physical Development Of Photographic Plates, George Higgins Jan 1937

Physical Development Of Photographic Plates, George Higgins

Proceedings of the Iowa Academy of Science

Physical development of photographic plates is not as efficient as chemical development. While it produces very fine grain negatives, longer exposure than normal is required and plates must be developed an hour to produce satisfactory printing densities. pH of the developer is important.

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Photomicrographs Of Snow Crystals, George C. Higgins Jan 1937

Photomicrographs Of Snow Crystals, George C. Higgins

Proceedings of the Iowa Academy of Science

This paper discusses techniques which have been developed for obtaining photomicrographs of snow crystals.

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A Semi-Automatic Film Slide Projector, H. C. Gilbertson Jan 1937

A Semi-Automatic Film Slide Projector, H. C. Gilbertson

Proceedings of the Iowa Academy of Science

Description of a projector designed for use in hallway displays.

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Position Of The Vibrator In The Experiments Of Melde And Kundt, B. J. Miller, L.O. Olsen Jan 1937

Position Of The Vibrator In The Experiments Of Melde And Kundt, B. J. Miller, L.O. Olsen

Proceedings of the Iowa Academy of Science

There is evident a fairly general misunderstanding of the location of the vibrator with respect to the nodes and loops in the string or air column in Melde's and Kundt's experiments. It is the purpose of this paper to call attention to the correct view; namely that for small damping, the vibrator is at an approximate node.

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Apparatus For Measuring Young's Modulus At Small Strains, James A. Van Allen Jan 1937

Apparatus For Measuring Young's Modulus At Small Strains, James A. Van Allen

Proceedings of the Iowa Academy of Science

A simple, easily constructed apparatus is described for the measurement of Young's Modulus of metal rods or bars under direct longitudinal stress, with total strain as low as 2 X 10-6 for a specimen of 10 cm. length. The extension of the specimen is magnified by a system consisting of two mechanical and two optical levers.

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A Repetition Of The Experiment On Teaching The Vernier, C. J. Lapp Jan 1937

A Repetition Of The Experiment On Teaching The Vernier, C. J. Lapp

Proceedings of the Iowa Academy of Science

A year ago a report was made on an experiment in teaching the vernier. The findings were so unexpected that the experiment was repeated in September, 1936, with almost the same results.

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A Study In Learning Electrodynamics By Motion Pictures, C. J. Lapp Jan 1937

A Study In Learning Electrodynamics By Motion Pictures, C. J. Lapp

Proceedings of the Iowa Academy of Science

The experimental sound picture on electrodynamics has recently been released. The principles illustrated were inventoried before and after the picture was shown. A study was made on the ability of students to transfer the principles to a new situation. Two sections were studied, one using the picture alone and the other using the picture with study aids. The findings are studied statistically.

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Brain Potentials During Silent And Oral Reading, John R. Knott Jan 1937

Brain Potentials During Silent And Oral Reading, John R. Knott

Proceedings of the Iowa Academy of Science

Brain potentials have been recorded during silence, during silent reading, and oral reading. While it has been assumed that potentials cannot be picked up during strong, complex stimulation, the results indicate that they can be. Analysis of the data indicates a hypothesis to the effect that complexity of cortical functioning is associated with complexity of the electrical activity of the cortex.

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Quantitative Measurement Of Some Psychological And Phonetic Factors Affecting The Incidence Of Stuttering, Spencer F. Brown Jan 1937

Quantitative Measurement Of Some Psychological And Phonetic Factors Affecting The Incidence Of Stuttering, Spencer F. Brown

Proceedings of the Iowa Academy of Science

A study reported in the Quarterly Journal of Speech (November, 1935) showed the existence of a phonetic factor of difficulty affecting the occurrence of stuttering spasms. Further analysis of the data on which the previous work was based has revealed a grammatical factor of difficulty. This is more consistent, but does not seem to be as important as the phonetic factor.

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Interval Preference, Curtis Tuthill Jan 1937

Interval Preference, Curtis Tuthill

Proceedings of the Iowa Academy of Science

Tuned intervals were paired with each member of a series of mistuned intervals and the subjects were asked to indicate which interval they preferred. The tuned intervals were those with the simple arithmetic ratios of the natural scale. The series of mistuned intervals, both flat and sharp, extended approximately half way to the next simple-ratio interval. Pure tones from beat frequency oscillators were used and the exact interval was tuned by means of Lissajous' figures on a cathode ray oscillograph. Mistuning, in terms of vibrations from the standard, was accomplished by the use of a variable pitch condenser.

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Trends Of Research In The Psychology Of Art, Mildred Dow Voss Jan 1937

Trends Of Research In The Psychology Of Art, Mildred Dow Voss

Proceedings of the Iowa Academy of Science

A broad survey of the field of psychology of art indicates that certain of the major trends are: (1) an increasing tendency to think of problems from the Gestalt point of view; (2) clarification of the distinction between appreciation and production of art.

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The Mental Development Of Children Of The Same I.Q. In Differing Institutional Environments, Orlo D. Crissey Jan 1937

The Mental Development Of Children Of The Same I.Q. In Differing Institutional Environments, Orlo D. Crissey

Proceedings of the Iowa Academy of Science

The purpose of this study is to investigate the mental development of children of the same mental level in relation to residence in institutional environments of differing mental level. The subjects consist of children resident in four Iowa childrens' institutions. They were selected from a large number of children who had been given individual tests, and who were resident in these institutions between an initial test and one or more retests. The Stanford and Kuhlmann Revisions of the Binet Scale were used for all individual tests, and were administered by well-trained examiners as a part of the cooperative program between …

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Do University And College Students Have Dislike Or Affection For Their Parents? An Attitude Scale For Personnel Procedures, Earle E. Emme Jan 1937

Do University And College Students Have Dislike Or Affection For Their Parents? An Attitude Scale For Personnel Procedures, Earle E. Emme

Proceedings of the Iowa Academy of Science

An understanding of the adjustment problems of university and college students reveals that many factors 2 are involved in student adjustment. To be sure, academic courses still constitute the main show for many students. Other students are very much interested in the so-called side shows, such as athletics, social relationships, economic and religious situations, the library, boarding and rooming conditions, as well as personal contacts with teachers in and out of classes, counselors and administrative officers. Consequently many students find themselves in a totality of campus on-rush, the roots and outreaches of which are not always known or understood.

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Beaver In Iowa, W. W. Aitken Jan 1937

Beaver In Iowa, W. W. Aitken

Proceedings of the Iowa Academy of Science

Beaver are generally assumed to have become extinct in Iowa, therefore the average Iowa citizen is startled when newspapers announce in headline type beaver activity in some apparently remote district of the state. These largest of all American rodents are not at all uncommon today in parts of the state. In fact, the increase of beaver population the past four years has now reached a point where their management presents a definite conservation problem.

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Bird Banding At Parsons College, Wesley H. Bartlett Jan 1937

Bird Banding At Parsons College, Wesley H. Bartlett

Proceedings of the Iowa Academy of Science

Although a number of operators have had charge of the station, headquarters has always been located at Parsons College. In January, 1931, the station was opened on the Parsons College campus, but the misdirected interest of students soon necessitated a change, and a small wooded tract, known as "Old Settler's Park," just northeast of the city limits was chosen. Here, during the greater part of each winter and spring, the traps have been set and operated. Summer months have seen other and more convenient locations utilized. A sub-station has been operated for three years during the Chimney Swift migration on …

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Additional Species Of Iowa Syrphidae, Mabel Jaques Jan 1937

Additional Species Of Iowa Syrphidae, Mabel Jaques

Proceedings of the Iowa Academy of Science

The family Syrphidae constitutes one of the largest families of the order Diptera. The individuals are medium to large in size and may be bare, pilose, or covered with thick pile. Some species are metallic blue or green in color, while others are vividly marked with yellow bands, spots, or stripes on all parts of the body, but especially on the abdomen.

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The Effects Of Mechanical Jarring Upon The Embryogeny Of Chick Embryos, Karl A. Stiles, Ray L. Watterson Jan 1937

The Effects Of Mechanical Jarring Upon The Embryogeny Of Chick Embryos, Karl A. Stiles, Ray L. Watterson

Proceedings of the Iowa Academy of Science

The results of this study indicate that jarring at frequent intervals throughout the first day of incubation exerts a deleterious influence on the developing embryo. Only in one instance did an egg jarred from the fourth to the twelfth hour of incubation develop normally and hatch. Sixty per cent of the embryos thus jarred died sometime between the second and third day of incubation. The others ceased to develop between the third and eleventh day of incubation.

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Effects Of Temperature On Oocysts Of Eimeria (Coccidia, Protozoa), K. Chang Jan 1937

Effects Of Temperature On Oocysts Of Eimeria (Coccidia, Protozoa), K. Chang

Proceedings of the Iowa Academy of Science

Unsporulated oocysts of Eimeria nieschulzi, E. miyairii, and E. separata were taken from the caeca of albino rats which had pure infections; unsporulated cocysts of E. tenella were secured from the caeca of experimentally infected chicks; unsporulated oocysts of E. arloingi, E. faurei, and E. ninakohl-yakimovi were obtained from fresh fecal droppings of young goats. They were concentrated by flotation in sugar solution and submitted to different temperatures (ranged 46° C. - 56° C.) and at various length of exposures in an electrically controlled water bath. The results demonstrated that unsporulated oocysts of different species of …

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Comparative Study In The Embryology Of The Turkey, N. W. Fugo Jan 1937

Comparative Study In The Embryology Of The Turkey, N. W. Fugo

Proceedings of the Iowa Academy of Science

It is a well-known fact that the incubation period for the turkey is seven days longer than that of the chicken. A comparative study is being made to ascertain in what respects the embryonic development of the turkey differs from that of the chicken. Observations show that the course of development runs slower in the turkey from the onset of incubation. The turkey embryo lags approximately 24-hours behind the chicken at the stage of closure of the amnion.

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Effect Of Nitrophenols On The Respiratory Metabolism Of Orthopteran Embryos, J. H. Bodine, E. J. Boell Jan 1937

Effect Of Nitrophenols On The Respiratory Metabolism Of Orthopteran Embryos, J. H. Bodine, E. J. Boell

Proceedings of the Iowa Academy of Science

When 2, 4-dinitrophenol (DNP) or 3, 5-dinitro-o-cresol (DNC) in suitable concentrations are added to isolated embryos of the grasshopper, Melanoplus differentialis, an immediate increase in the oxygen uptake of the embryos is noted. Respiration of either blocked or developing embryos in the presence of the nitrophenol varies between 200 and 300 per cent of the normal and may continue at a uniform rate for several hours.

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