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Note On The Hydrolysis Of Nitrobenzene, H. F. Lewis, G. W. Thiessen
Note On The Hydrolysis Of Nitrobenzene, H. F. Lewis, G. W. Thiessen
Proceedings of the Iowa Academy of Science
Wohl describes the oxidation of nitrobenzene to nitrophenols by the action of powdered potassium hydroxide at temperatures between 60° and 90° C. This reaction does not take place under similar conditions with solid sodium hydroxide.
Indian Quartzite Quarry Near Hot Springs, South Dakota, Paul Rowe
Indian Quartzite Quarry Near Hot Springs, South Dakota, Paul Rowe
Proceedings of the Iowa Academy of Science
Bottle Mountain east of Hot Springs, South Dakota is the traditional last fortress of the Indian tribes occupying the region. On the southwest face of this mountain there is evidence that the Indians removed a considerable amount of the rock best fitted for making arrow points. There is considerable loose talus, apparently rejected blocks, about the foot of the slope at this place. Elsewhere there is little talus. Some of the joints have been widened into small caves by the continual "fracturing" of the most desirable rock for making artifacts.
Phenomena Of Cathode Sputtering, K. V. Manning
Phenomena Of Cathode Sputtering, K. V. Manning
Proceedings of the Iowa Academy of Science
When metal is deposited cathodically upon a glass plate a film is found upon the side of the plate away from the cathode. In the study of this deposit both alternating and direct potentials were employed. An attempt to increase the deposit by various reflecting surfaces gave negative results. A possible explanation of the phenomenon is offered, based upon the assumption that the metallic particles receive a positive charge after leaving the cathode. An attempt to sputter non-conductors in the form of metallic oxides gave negative results.
Electrical Constants Of Dielectrics For Radio Frequency Currents, R. V. Guthrie Jr.
Electrical Constants Of Dielectrics For Radio Frequency Currents, R. V. Guthrie Jr.
Proceedings of the Iowa Academy of Science
The electrical constants of dielectrics are the power factor and the dielectric constant, the power factor being that of a carefully insulated condenser using the given material as the dielectric. Losses in a condenser may be represented either as a series or a parallel resistance. If considered as in series, the losses may be determined by resistance variation, and if in parallel, the geometric capacity may be determined. From a consideration of both, the power factor ψ and dielectric constant K may be obtained from simple formulae. An investigation of several solid dielectrics over a band of frequencies ranging from …
Measurement Of The Acoustic Impedance Of A Branch Line, G. W. Stewart
Measurement Of The Acoustic Impedance Of A Branch Line, G. W. Stewart
Proceedings of the Iowa Academy of Science
Acoustic measurement is in its infancy and that of acoustic impedance is peculiarly difficult. A theory of a new method of the measurement of acoustic impedance is presented herewith. How useful it may become must be determined through experience.
The Effect Of Vitamin Deficiency On Blood Pressure In Rats, H. B. Cook, F. M. Baldwin
The Effect Of Vitamin Deficiency On Blood Pressure In Rats, H. B. Cook, F. M. Baldwin
Proceedings of the Iowa Academy of Science
After devising a very delicate, modified recording mercury manometer, it was found possible to obtain direct blood pressure curves from the abdominal aorta of anaesthetised rats, previously fed upon specific normal and vitamin deficient diets and thus make comparisons. About 75 animals were used, one-half of this number being normals to check about equally against A and B deficient animals. The records from 22 normals, on growing rations, showed an average of 84 mm. Hg, with the exception of one extremely high and one extremely low figure. The majority were close to the general average. This figure is strikingly close …
Notes On The Oyster-Shell Scale, Lepidosaphes Ulmi, Linn, R. L. Webster
Notes On The Oyster-Shell Scale, Lepidosaphes Ulmi, Linn, R. L. Webster
Proceedings of the Iowa Academy of Science
Several years' records of dates on which the eggs of this insect hatched at Ames, Iowa.
1924 Old Gold, Iowa State Teachers College
1924 Old Gold, Iowa State Teachers College
UNI Yearbooks
The student yearbook of the Iowa State Teachers College, later known as the University of Northern Iowa.
The Preparation Of Permanent Filter Mats For Gooch Crucibles, G. N. Quam, H. V. Wright
The Preparation Of Permanent Filter Mats For Gooch Crucibles, G. N. Quam, H. V. Wright
Proceedings of the Iowa Academy of Science
A porcelain filter mat has been made (Sweeney and Quam - J.A.C.S. 46, 958, 1924) which withstands the heat of a blast lamp, remains constant in weight after repeated washing with aqua regia, has uniform porosity, and has the advantages of a Monroe crucible. Methods of standardizing the mats are being studied. The building of silica filter mats in silica crucibles is being investigated. Preliminary results indicate that a silica mat can be made according to the plan of the porcelain mat and have the added advantages that silica affords.
Utilization Of Chinic Acid In The Differentiation Of The Colon-Aerogenes Groups, Buford H. Butcher
Utilization Of Chinic Acid In The Differentiation Of The Colon-Aerogenes Groups, Buford H. Butcher
Proceedings of the Iowa Academy of Science
Beijerinck in 1911 called attention to the fact that some strains of Bact. aaerogenes produce from chinic acid and a ferric salt, a red to black coloration under aerobic conditions. Strains of Bact. coli, he stated, do not color the medium under similar conditions. Under anaerobic conditions in solutions of chinate salt, a fermentation may occur with some members of the aerogenes group, whereby carbonic, acetic and propionic acids are formed. At the Iowa State College laboratory an attempt was made to duplicate this anaerobic type of fermentation by organisms of the coli-aerogenes group but without success. Both Smith and …
Lilium Michiganense Farw. In Iowa, Wier R. Mills
Lilium Michiganense Farw. In Iowa, Wier R. Mills
Proceedings of the Iowa Academy of Science
With Lilium philadelphicum or the variety andinum this paper has nothing to do. We are concerned with the problem presented in an attempt to classify the wild lily of Iowa which in the past was referred to Lilium superbum by many botanists, and by others to Lilium canadense. In the herbarium at Iowa State College are specimens of lilies sent from different sections of Iowa and labeled Lilium superbum and Lilium canadense by those collecting the specimens. Mr. Cratty, the curator of the herbarium, kindly permitted the writer to examine these specimens and it was found that they were evidently …
Three Maxims For The Study Of The Nutrition Of Microorganisms, Ellis I. Fulmer
Three Maxims For The Study Of The Nutrition Of Microorganisms, Ellis I. Fulmer
Proceedings of the Iowa Academy of Science
I. The relative potencies of two materials cannot be arrived at by the comparison of the effects of the two materials at equal concentrations. Corollary: The effect of treatment upon the potency of a material cannot be determined by the comparison of the treated and untreated material at equal concentrations. II. The relative potencies of two materials at one temperature may not be true for any other temperature. Corollary: Temperature coefficients for the effect of a material must be determined under optimum conditions for each temperature. III. If two materials are to be compared as a source of a protoplasmic …
The Manufacture Of Oxalic Acid From Corn Cobs, H. A. Webber
The Manufacture Of Oxalic Acid From Corn Cobs, H. A. Webber
Proceedings of the Iowa Academy of Science
Oxalic acid is obtained from corn cobs by subjecting the cobs to the oxidizing action of nitric acid (sp.gr.1.5) in the presence of catalysts, as V2 O5, M0, O3. The cobs, ground to 1/8” mesh, are treated either hot or cold. In the hot method, the heat is removed after decomposition of the cobs (about 5 minutes.) In the cold process, the mixture of cobs, acid, and catalyst is allowed to stand three days. An average yield of 70% is obtained by either method, but greater yields are obtained occasionally. About 5% of …
Notes On Audio Methods Of Determining Null Points In Chemical Tests, Edwin Kurtz
Notes On Audio Methods Of Determining Null Points In Chemical Tests, Edwin Kurtz
Proceedings of the Iowa Academy of Science
The standard method of determining the presence of small currents and their null points has been by the use of the galvanometer. This method has its advantages, namely; one can get some idea of the size of the current by noting the magnitude of deflection, and noise and quality of eyesight have no material effect on the accuracy obtainable. However, in spite of these apparent advantages, the ultimate accuracy of this method is limited principally by the sensitivity of the galvanometer. If a very sensitive galvanometer is used it is delicate and not very rigid nor serviceable. Furthermore the deflections …
Pennsylvanian As A Periodic Title For Iowa Coal Measures, Charles Keyes
Pennsylvanian As A Periodic Title For Iowa Coal Measures, Charles Keyes
Proceedings of the Iowa Academy of Science
One phase of the inapplicability of the unfortunate title of Pennsylvanian as sometimes used for our Iowa rocks is a theme which was presented a year ago before this Academy. Today, another strange aspect of the same topic is stressed. Now, it is not at all likely that the term Pennsylvanian in Geology as a periodic title world-wide in significance, will ever come into general, or international usage to take the place of Coal Measures, which name for more than a century enjoys this privilege. The violations of the accepted canons of scientific nomenclature are too many and too grave …
Preliminary Report On The Optical Properties Of Magnesium, M. E. Graber
Preliminary Report On The Optical Properties Of Magnesium, M. E. Graber
Proceedings of the Iowa Academy of Science
The present research on the optical properties of single magnesium crystals was carried forward in the laboratories of the University of Iowa under the direction of Prof. L. P. Sieg. Employing the crystelliptometer, plane polarized monochromatic light was reflected from the crystal surface and the resultant elliptically polarized light analyzed to determine the phase and azimuth angles of its components. The crystals were studied in two positions: parallel and perpendicular, respectively, to the principle axis of the crystal, and two sets of optical constants (index of refraction, absorption index and reflecting power) were determined. Within the range of wave lengths …
Photochemical Distribution On The Retina As Shown By The Perimeter, Francis Marsh Baldwin
Photochemical Distribution On The Retina As Shown By The Perimeter, Francis Marsh Baldwin
Proceedings of the Iowa Academy of Science
The extent of the visual field, as well as the distribution of photochemical substances upon it, has been a study of very great interest ever since the end of the eighteenth century, when the English chemist, Dalton, made the classical study upon himself. He was unable to distinguish the various shades of red and for a considerable time afterwards this particular deficiency in color discrimination was termed, "Daltonism." During the latter part of the nineteenth century the subject was given practical importance by a number of observers, especially by the researchers of Holmgren the Swedish physiologist who emphasized its bearing …
Notes On The Biology Of The Leafhopper Eutettix Strobi Fitch, F. A. Fenton
Notes On The Biology Of The Leafhopper Eutettix Strobi Fitch, F. A. Fenton
Proceedings of the Iowa Academy of Science
In the vicinity of Ames, Iowa, the leaves of the common pigweed or lamb's quarters, Chenopodium album L. are frequently spotted with a brilliant reddish discoloration. This is due, as Osborn first noted, to the feeding punctures of a small leafhopper, Eutettix strobi Fitch. The writer has observed this species at Ames for several years and has accumulated some scattered notes on its life cycle and also the method of its injury to the pigweed leaves. Since several species of leafhoppers are now known to transmit or carry various plant pathogens, it is thought that these few notes may be …
Drainage In Iowa, B. Shimek
Drainage In Iowa, B. Shimek
Proceedings of the Iowa Academy of Science
Recently a number of interviews have appeared in the papers of the state to the effect that drainage has not affected rainfall in Iowa, and their evident purpose is to excuse and encourage the continuance of the policy of indiscriminate drainage which has been practiced in our state. Our legislators and the people of the state should understand that this argument is wholly beside the question involved, and that its only effect can be to becloud the issue and lead our attention away from the real questions which should receive our consideration.
The Address Of The President - A Century Of Botany In Iowa, L. H. Pammel
The Address Of The President - A Century Of Botany In Iowa, L. H. Pammel
Proceedings of the Iowa Academy of Science
A Century of Botany-It is certainly a pleasure to greet you here on this occasion, especially so, because of the nature of the honorable work performed by the scientists of the State of Iowa. It is customary for the retiring president to deliver an address of some kind. In looking over topics which have been chosen by various retiring presidents I find such titles as "Local Problems in Science," "What We Have Been Doing," "The Academy and the People," "Science of One Hundred Years Ago," "Some Problems of Heredity and Evolution," "Two Centuries of North American Lichenology," "Botany in Its …
Studies On The Role Of Rye In The Vienna Process For Yeast Manufacture, Ellis I. Fulmer, Roma Elmer
Studies On The Role Of Rye In The Vienna Process For Yeast Manufacture, Ellis I. Fulmer, Roma Elmer
Proceedings of the Iowa Academy of Science
A water extract of rye shows an optimum concentration for its effect in causing top growth of yeast. Quantitative studies were reported on the distribution of the yeast throughout a column with various concentrations of the extracts at varying stages in fermentation. Data are discussed relative to the effect of various concentrations of the extract upon the composition of the yeast especially with reference to fat content.
Adsorption From Salt Solutions By Colloidal Copper Ferrocyanide, Mikkel Frankert, J. A. Wilkinson
Adsorption From Salt Solutions By Colloidal Copper Ferrocyanide, Mikkel Frankert, J. A. Wilkinson
Proceedings of the Iowa Academy of Science
In order to compare the two views as to the cause of the acidity developed when a soil is treated with a neutral salt solution (selective adsorption and base exchange theories) colloidal copper ferrocyanide was treated with different salt solutions of varying strengths and the alkalinity or acidity developed was compared with the amount of copper dissolved. Potassium salts developed a whole series from a small amount of acidity to a large amount of alkalinity.
A Fossil Pine Cone From Drift Of Northern Iowa, A. O. Thomas
A Fossil Pine Cone From Drift Of Northern Iowa, A. O. Thomas
Proceedings of the Iowa Academy of Science
A cast of a pine cone composed of limonite was recently found in a gravel pit near Britt. Its composition and appearance suggest considerable antiquity. It is thought to belong to a Mesozoic or Tertiary Sequoia
A Method Of Measuring Rates Of Corrosion Of Iron In The Presence Of Carbon Dioxide And Air And The Influence Of Electrical Potentials On Such Rates, Anson Hayes, E. Lee Henderson, C. E. Staneart, G. H. Brodie
A Method Of Measuring Rates Of Corrosion Of Iron In The Presence Of Carbon Dioxide And Air And The Influence Of Electrical Potentials On Such Rates, Anson Hayes, E. Lee Henderson, C. E. Staneart, G. H. Brodie
Proceedings of the Iowa Academy of Science
The method consists in subjecting cylindrical samples of 4ft. by 1/10 ft. wrought iron to the action of water saturated with the gas mixture. The water and gas are passed through the cell at such a rate as to insure a constant and known composition. A precision of 5% is obtained in runs of 48 hours duration. 4% CO2 mixed with air dissolves 1 gram of iron per square centimeter of exposed surface in 735 days while it required 1927 days with air alone. A fall of 25/100 millivolt per centimeter increased the rate of corrosion 28%. 25/1000 millivolt …
Spontaneous Decomposition Temperatures Of Potassium Chlorate-Iron Oxide Mixtures, F. E. Brown, C. O. White
Spontaneous Decomposition Temperatures Of Potassium Chlorate-Iron Oxide Mixtures, F. E. Brown, C. O. White
Proceedings of the Iowa Academy of Science
Potassium chlorate and the oxides of iron were mixed in varying proportions and the spontaneous decomposition temperatures of the mixtures determined. Fe3O4 prepared at high temperatures exerted very little catalytic effect and no rapid evolution occurred below 374 ° in a mixture whose composition was KClO3: Fe3O4:: 1: 1. A monohydrate of Fe3O4 prepared by precipitation was magnetic as precipitated. A 1: 1 mixture of this oxide with KClO3 suffered spontaneous decomposition at 294°. A freshly prepared sample of Fe2O3 was used with KClO …
A Simple Automatic Mercury Pump Which Permits The Collection Of The Exhaust Gas, H. M. Mclaughlin, F. E. Brown
A Simple Automatic Mercury Pump Which Permits The Collection Of The Exhaust Gas, H. M. Mclaughlin, F. E. Brown
Proceedings of the Iowa Academy of Science
The Toepler pump has been modified so that it operates continuously and automatically, maintains a high vacuum, guards completely against the inclusion of air in the exhaust gas, and is easily made by the ordinary chemical experimenter. A water pump at M lowers the mercury in E, F and at the same time draws mercury into K through N. Mercury is raised in E, F by atmospheric pressure through N as soon as the surface of the mercury in U is below the lower end of the tube N. Gas from the apparatus is forced out through F, G into …
New Measurements In The Process Of Reading, E. O. Finkenbinder
New Measurements In The Process Of Reading, E. O. Finkenbinder
Proceedings of the Iowa Academy of Science
The lectometer is a special form of tachistoscope which provides a connection with a chronoscope. Through an open, adjustable sector of a rotating disc is presented material for reading. Just as the view is shut off a small arm attached to the spindle of the disc dips into mercury, thus completing an electric circuit which sets the chronoscope into action. The observer reads into a voice key which stops the chronoscope and gives the time to the thousandth of a second it takes him to know and say what he had observed during the short view.
Inheritance Of Carbohydrates And Fat In Corn, E. W. Lindstrom, F. Gerhardt
Inheritance Of Carbohydrates And Fat In Corn, E. W. Lindstrom, F. Gerhardt
Proceedings of the Iowa Academy of Science
Chemical analyses of cross-bred ears, involving the yellow dent (Iodent) and white Evergreen sweet corn varieties, have yielded some interesting results with respect to the detailed mode of inheritance of sugars, dextrins, starches, and fat. High sugar and dextrin (also low starch) are distinctly recessive in inheritance, although there is a small cumulative effect of the genetic factors represented in the endosperm development with its 3x condition. No such cumulative effect is present with respect to fat, the hybrids (made reciprocally) having identical values, intermediate in percentage, but with a slight tendency towards a dominance of low fat. Carbohydrate and …
Beginnings Of Desert In Iowa, Charles Keyes
Beginnings Of Desert In Iowa, Charles Keyes
Proceedings of the Iowa Academy of Science
Iowa, with its thirty odd inches of annual rainfall, is at the present time well within the garden tracts of Earth. Today we are really living in the middle of an interglacial epoch which does not yet reach its arid zenith. Were we not fully cognizant of this circumstance, and were we not looking for some first traces of such climatic transmutations, as in childhood we hunt for four-leaved clover, the clues might easily escape notice. Being on the alert, however, smallest signs are replete with deepest significance. It thus happens that our future desert conditions are already in sight, …