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Comparison Of X-Ray Diffraction In H2o And H2/2o, G. W. Stewart Jan 1934

Comparison Of X-Ray Diffraction In H2o And H2/2o, G. W. Stewart

Proceedings of the Iowa Academy of Science

It is to be assumed that the forces in a molecule are approximately invariant for an isotopic change in mass. Consequently the x-ray diffraction curves for H2O and H2/2O, determined by the structure of the corresponding liquid, may be expected to be nearly alike. Experiment by x-ray diffractions shows this to be the case, for the differences are well within experimental error and are not as much as 1% over the greater part of the diffraction-intensity-angle curves.

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Mean Free Paths Of Molecules And The Wave Mechanics, John A. Eldridge Jan 1934

Mean Free Paths Of Molecules And The Wave Mechanics, John A. Eldridge

Proceedings of the Iowa Academy of Science

Direct experimental determination of the mean free paths of hydrogen, nitrogen and oxygen have led to a value of the effective cross section of the molecule between 4 and 5 times greater than that obtained from viscosity measurements. Massey and Mohr have shown that assuming the rigid sphere molecule the wave mechanics leads to a difference in the values; the theoretical ratio, however, is not greater than 2.

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The Mosses Of Southwestern Iowa, Geneva Sayre, H. S. Conard Jan 1934

The Mosses Of Southwestern Iowa, Geneva Sayre, H. S. Conard

Proceedings of the Iowa Academy of Science

The territory of southwestern Iowa in this report includes Harrison, Shelby, Audubon, Guthrie, Pottawatamie, Cass, Adair, Mills, Montgomery, Adams, Union, Fremont, Page, Taylor and Ringgold counties. Four of these border the Missouri state line and four are along the Missouri river. About half the region is prairie, unmodified by erosion or the deposition of loess in hills. The mosses were collected on the wooded banks of streams or in cultivated land. The collections were made mostly by Dr. Conard during 1930-1933. They are obviously incomplete. In some counties only one stop was made for collecting, in others the work was …

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Weathering Of Sandstone In The Iowa State Capitol Building, C. S. Gwynne Jan 1934

Weathering Of Sandstone In The Iowa State Capitol Building, C. S. Gwynne

Proceedings of the Iowa Academy of Science

Extreme weathering of some of the sandstone in the superstructure of the Iowa State Capitol at Des Moines has within recent years been a cause of considerable concern. The part of the building affected is that above the level of the basement story, and it is greatest toward the top of the building. Decorations, balustrades, cornices, architraves, pediments, hereafter to be referred to as trimmings and decorations, have been affected to the point where many pieces have fallen and crumbled away. The falling material is a source of danger, the appearance of the building is unfavorably affected, and the monetary …

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An Approach To The Study Of Social Behavior In Children, Harold M. Williams Jan 1934

An Approach To The Study Of Social Behavior In Children, Harold M. Williams

Proceedings of the Iowa Academy of Science

In the present study of social development, the situation-response analysis has been used as the primary basis. On this basis the actual behavior of children in concretely described situations has constituted the primary data. Previous experiments have almost without exception used the technique of rating individual children on certain social traits. These ratings have usually been made on the basis of the observer's general impression. When the original records are made in terms of such traits it becomes at once impossible to get beyond such ratings to the primary concrete events which presumably constituted the basis for the ratings. When …

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Table Of Contents Jan 1934

Table Of Contents

Proceedings of the Iowa Academy of Science

No abstract provided.

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In Memoriam: Thomas Huston Macbride; Henry Fredrick Wickham; Herbert Grant Campbell; Omar E. Lowman; Floyd August Nagler, B. Shimek, Frank A. Stromsten, T. C. Stephens, R. M. Hixon, F. E. Brown, S. M. Woodward Jan 1934

In Memoriam: Thomas Huston Macbride; Henry Fredrick Wickham; Herbert Grant Campbell; Omar E. Lowman; Floyd August Nagler, B. Shimek, Frank A. Stromsten, T. C. Stephens, R. M. Hixon, F. E. Brown, S. M. Woodward

Proceedings of the Iowa Academy of Science

No abstract provided.

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The Address Of The President - Science And The Future, E. J. Cable Jan 1934

The Address Of The President - Science And The Future, E. J. Cable

Proceedings of the Iowa Academy of Science

We are truly living in a wonderful and fearful period so far as civilization is concerned. Our present social order has changed so rapidly within the last quarter of a century as to cause many writers and students of sociology to become somewhat alarmed as to its future stability. The concept of progress is one of the most profound and germinal ideas at work in our modern age.

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Fermentation Of Artichokes, Howard Reynolds, C. H. Werkman Jan 1934

Fermentation Of Artichokes, Howard Reynolds, C. H. Werkman

Proceedings of the Iowa Academy of Science

The application of fermentative processes to the problem of the industrial utilization of agricultural products and by-products for the production of organic acids and 'solvents' has been approached from a number of angles. During the course of related studies the possibility of the fermentative utilization of artichoke tubers was considered. In many ways this plant would provide an agricultural product highly suited to such purposes. The artichoke is indigenous to North America and grows freely in all parts of the country. It can be machine cultivated in the same manner as corn and can be stored in the ground until …

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Leaf Surface Of A Twenty-One-Year Old Catalpa Tree, Franklin M. Turrell Jan 1934

Leaf Surface Of A Twenty-One-Year Old Catalpa Tree, Franklin M. Turrell

Proceedings of the Iowa Academy of Science

Opportunity for leaf count and area measurement of the foliage of an entire tree was afforded when on August 25, 1933 a catalpa (Catalpa speciosa) was felled on the west side of the Old Capitol on the University of Iowa Campus. The tree was located seventy-six feet southeast of the intersection of the east walk of Madison Street and Iowa Avenue. It stood on an open lawn near the base of a long five percent slope, removed more than 150 feet from any large trees on the east or south, therefore receiving direct sunlight throughout the morning and early afternoon. …

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Notes On Iowa Mosses - Vi, Lucy M. Cavanagh Jan 1934

Notes On Iowa Mosses - Vi, Lucy M. Cavanagh

Proceedings of the Iowa Academy of Science

In a paper presented before this Academy in 1931, the writer reported a species of Fabronia under the name F. gymnostoma. The species was collected by Dr. B. Shimek August 16, 1916, near West Lake Okoboji, where it occurred very sparingly near the base of a large partly decorticated red cedar (Juniperus virginiana). Only a few old fruits were found. There were no peristomes, but a few rather ragged cells at the mouth of the capsule were taken to be a remnant of a membrane which closed the opening as in F. gymnostoma.

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Some Methods Of Labeling Nature Trails, John Moore Jan 1934

Some Methods Of Labeling Nature Trails, John Moore

Proceedings of the Iowa Academy of Science

For several years the students of botany of Iowa Wesleyan College have maintained a nature trail in the Oakland Mills State Park. The writer is one of the three students appointed to take care of this work for the current year. When the trails were first inaugurated it was necessary to select the course, lay out the path and erect signs to keep the visitors going in the right direction, as well as to label items of interest. Now through the activity of the C.C.C. workers, permanently constructed paths run through the highly interesting parts of the park and one …

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Shortening The Rest Period Of The Tubers Of The Jerusalem Artichoke, Helianthus Tuberosus L., E. S. Haber Jan 1934

Shortening The Rest Period Of The Tubers Of The Jerusalem Artichoke, Helianthus Tuberosus L., E. S. Haber

Proceedings of the Iowa Academy of Science

Experiments are reported in which the rest period of dormant tubers of the Jerusalem artichoke was shortened by storage at temperatures near or slightly below freezing. The length of the rest period or dormant stage was directly dependent on storage temperature; the lower the temperature down to slightly below freezing, the shorter the rest period.

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Notes On The Life History Of Aphanizomenon Flos-Aquae, E. T. Rose Jan 1934

Notes On The Life History Of Aphanizomenon Flos-Aquae, E. T. Rose

Proceedings of the Iowa Academy of Science

Aphanizomenon flos-aquae for the past few years has been an extremely serious pest in a number of the lakes of northwestern Iowa. Curiously enough, this common blue-green alga has not received much attention other than taxonomic technicalities. This paper deals chiefly with the life history and economic importance of this, and other algal pests.

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The Basidium, Donald P. Rogers Jan 1934

The Basidium, Donald P. Rogers

Proceedings of the Iowa Academy of Science

The current systems of classification of the basidiomycetes tend to attribute greater weight to the structure of the fruiting-body than to basidial morphology. Actually, basidial morphology is the more fundamental character. When the basidium is considered in the light of Neuhoff's hypo-, epibasidium and Donk's pro-, metabasidium concepts, homologies appear which furnish the basis for a natural arrangement of the class. Such an arrangement follows the general groupings proposed by Patouillard of Hetero- and Autobasidiomycetes and of Hymeniales and Gasteromycetes. The relationships, mutual and within the groups, of Patouillard's divisions receive greater meaning from such a consistent morphological and phylogenetic …

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On The Significance Of The Minor Venation Of Foliage Leaves, Robert B. Wylie Jan 1934

On The Significance Of The Minor Venation Of Foliage Leaves, Robert B. Wylie

Proceedings of the Iowa Academy of Science

Experiments with living mesophytic foliage leaves show that the smaller veins are capable of carrying enormously increased overload. There seems to be no structural modification of the minor veins in meeting these increased demands.

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Inheritance Of Fruit Shapes And Sizes In The Pepper And Tomato, E. W. Lindstrom Jan 1934

Inheritance Of Fruit Shapes And Sizes In The Pepper And Tomato, E. W. Lindstrom

Proceedings of the Iowa Academy of Science

Both Capsicum and Lycopersicum exhibit the same correlation between fruit shape and fruit size, a correlation which is wholly lacking for the same characters in the Cucurbits. In the pepper both positive and negative correlations of shape and size were discovered in F2 generations, the sign of the correlation being dependent on the parental combinations. Accordingly the cause for the correlations must be the genetic one of linkage, due to the presence of shape and size genes on the same chromosome, a fact which has already been reported for the tomato. Fruit sizes in both genera exhibit logarithmic rather …

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Plant Cover Map Of The Lake Wapello Watershed, David County, Iowa, Albert F. Dodge Jan 1934

Plant Cover Map Of The Lake Wapello Watershed, David County, Iowa, Albert F. Dodge

Proceedings of the Iowa Academy of Science

A plant cover map of the land comprising the five thousand acre watershed of Lake Wapello has been made in connection with erosion control, lake silting and game management problems confronting the Iowa Fish and Game Commission in the development of this southern Iowa fishing lake. The extent of various cover types with the important species composing each type and the per-of soil erosion areas on the map permits the correlation of extent of erosion with plant cover. The locations of the pictures presented has been recorded so that successional changes in vegetation may be traced.

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A Comparison Of Different Types Of Glass Electrode For Determining The Ph Of Soils, Harold L. Dean, R. H. Walker Jan 1934

A Comparison Of Different Types Of Glass Electrode For Determining The Ph Of Soils, Harold L. Dean, R. H. Walker

Proceedings of the Iowa Academy of Science

During the past decade the quinhydrone electrode has been used extensively for determining the hydrogen-ion concentration of soils. It is admirably adapted to the study of reaction in soils due to its simplicity and ease of operation, and to its accuracy in most soils. As is well known, however, its use is restricted to soils having a reaction less than pH 8.0 to 8.5, and to soils containing no oxidizing or reducing substances in sufficient concentration to affect the oxidation-reduction potential of the quinhydrone. In recent years a number of investigators, notably Karraker, McGeorge, Baver, and Heintze and Crowther, have …

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The Influence Of Salts On The Velocity Of Inversion Of Sucrose At 25°, J. N. Pearce, Margaret Thomas Jan 1934

The Influence Of Salts On The Velocity Of Inversion Of Sucrose At 25°, J. N. Pearce, Margaret Thomas

Proceedings of the Iowa Academy of Science

The velocity of inversion of sucrose has been determined in the presence of salts of different ion-types at 25°. In the solutions used the concentrations of three components are definitely fixed, namely: sucrose 0.1 m., hydrochloric acid 1.0 m., and water 1000 grams. The salt concentration is the only variable. The salts used were LiCl, NaCl, KCl, BaCI2 and Al(No3)3. For equal molal concentrations of the different salts the velocity coefficients increase in the order: KCl23)3. The salt effect appears to be explained best on the basis of ionic hydration due …

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The Thermal Decomposition Of Hexane At High Pressures, J. N. Pearce, J. W. Newsome Jan 1934

The Thermal Decomposition Of Hexane At High Pressures, J. N. Pearce, J. W. Newsome

Proceedings of the Iowa Academy of Science

The thermal decomposition of n-hexane has been studied at pressures between 14,000 and 15,000 lbs., at temperatures between 430° and 520°' and for heating periods varying from a few minutes to two hours.

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The Adsorption Of Certain Ketones And Esters By Activated Charcoal, J. N. Pearce, A. C. Hanson Jan 1934

The Adsorption Of Certain Ketones And Esters By Activated Charcoal, J. N. Pearce, A. C. Hanson

Proceedings of the Iowa Academy of Science

The adsorption of acetone, methyl-ethyl ketone, diethyl ketone, ethyl formate, ethyl acetate, n-propyl acetate and methyl propionate by activated charcoal has been measured for temperatures between 0° and that of decomposition. The Langmuir isotherms, obtained by plotting p/x/m against the pressure p, are rectilinear at the lower temperatures and up to 60 mm. pressure. At higher temperatures and pressures the isotherms tend to deviate from the straight line and bend toward the pressure axis. The amount of vapor adsorbed per gram of charcoal decreases with increase in the complexity of the adsorbed vapor molecules; further it is found to decrease …

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The Dipole Moments Of Certain Organic Compounds, J. N. Pearce, L. F. Berhenke Jan 1934

The Dipole Moments Of Certain Organic Compounds, J. N. Pearce, L. F. Berhenke

Proceedings of the Iowa Academy of Science

The dielectric constants and densities of dilute solutions of p-brombenaldehyde, p-tolualdehyde, p-hydroxybenzaldehyde and p-anisaldehyde in dioxane were measured at 25°. From the total polarization and the molecular refractivities the dipole moments were calculated to be 2.20, 3.27, 4.18 and 3.70x10-18 e.s.u., respectively. The angle between the aldehyde group moment direction and the line through the l, 4 C atoms of the benzene nucleus is calculated to be 51°. The angles between the directions of the OH and CHO group moments, and, between the CH3O and CHO group moments are 50° and 49°, respectively. The angle between the …

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The Effect Of Fluorine On Blood And Respiration, D. A. Greenwood, E. A. Hewitt, V. E. Nelson Jan 1934

The Effect Of Fluorine On Blood And Respiration, D. A. Greenwood, E. A. Hewitt, V. E. Nelson

Proceedings of the Iowa Academy of Science

Much interest has been manifested in fluorine during the past few years. This is due to two reasons: first, fluorine is found in several phosphatic mineral supplements, which are fed to farm animals ; and, second, fluorine has been found in drinking waters in this and many other countries of the world. The interest of the authors in fluorine dates from the discovery by Ostrem, Nelson, Greenwood, and Wilhelm of fluorine in the drinking waters of communities in the State of Iowa, with the resulting production of mottled enamel of the teeth. There can be no question that fluorine in …

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Use Of Copper To Increase The Yield Of Ethyl Bromide, Philip Hendrixson Jan 1934

Use Of Copper To Increase The Yield Of Ethyl Bromide, Philip Hendrixson

Proceedings of the Iowa Academy of Science

It has been discovered that the addition of copper punchings to small quantities of the reaction mixture of 95 per cent ethyl alcohol, sulfuric acid, water, and sodium bromide increases the yield of ethyl bromide from 57 per cent obtained without the copper to 80 per cent. The copper reacts with the sulfuric acid producing sulfur dioxide which reduces any bromine formed back to bromide ion and thus prevents a loss of bromine and, of course, increases the yield. The presence of copper as a reducing agent prevents formation of free bromine.

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The Availability Of Tryptophane Derivatives For Supplementing Diets Deficient In Tryptophane, Clarence P. Berg, H. Everett Hanson Jan 1934

The Availability Of Tryptophane Derivatives For Supplementing Diets Deficient In Tryptophane, Clarence P. Berg, H. Everett Hanson

Proceedings of the Iowa Academy of Science

The utilization of tryptophane for growth in the rat can be effectively prevented by benzoylation, but not by acetylation or by esterification with ethyl alcohol. For the purpose of extending these observations, the phenylacetyl, phenylpropionyl, and propionyl derivatives of tryptophane, as well as the phenyl and benzyl ester hydrochlorides, were prepared and fed as supplements in a diet deficient in tryptophane. Of these derivatives, only phenylacetyltryptophane failed to produce growth. Presumably all of the others undergo enzymatic cleavage and hence can be utilized as well as free tryptophane for purposes of growth.

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Orientation In The Dibenzofuran Series, W. G. Bywater, E. W. Smith, G. E. Brown, H. Gilman Jan 1934

Orientation In The Dibenzofuran Series, W. G. Bywater, E. W. Smith, G. E. Brown, H. Gilman

Proceedings of the Iowa Academy of Science

In connection with physiological properties of dibenzofuran types it was necessary first to determine the position assumed on the introduction of one substituent into the parent type; and, second, the effect of a substituent already present on the position assumed by a second substituent.

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A Study Of Total And Reduced Glutathione With Oxygen Content And Capacity In The Blood Of Pregnant And Non-Pregnant Women, Fred W. Oberst, E. B. Woods Jan 1934

A Study Of Total And Reduced Glutathione With Oxygen Content And Capacity In The Blood Of Pregnant And Non-Pregnant Women, Fred W. Oberst, E. B. Woods

Proceedings of the Iowa Academy of Science

Much speculation has been offered as to the exact nature and function of glutathione in circulating blood. It has often been considered as playing some part in cell respiration. A study has been made on total and reduced glutathione content of blood in the non-pregnant, in the pregnant during the labor and the parturition including cord blood, during the postpartum four-ten days, and in the toxemias of pregnancy. This offered an opportunity to study the relation between total and reduced glutathione in blood under conditions of varying oxygen content and capacity of systemic blood. The study also included a group …

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The Oxidation Of Glucose By Rhizobium Meliloti, O. R. Neal, R. H. Walker Jan 1934

The Oxidation Of Glucose By Rhizobium Meliloti, O. R. Neal, R. H. Walker

Proceedings of the Iowa Academy of Science

The extent of oxidation of glucose by Rhizobium meliloti has been determined by comparing the amount of oxygen consumed with the theoretical amount necessary for complete oxidation to carbon dioxide and water. With M/540, M/270, and M/180 concentrations of glucose as a substrate, the rate of oxygen consumption increased rapidly for a period of from 4 to 8 hours then decreased to a low and fairly constant value. The total consumption of oxygen was approximately one-third of the amount required for complete oxidation of the glucose.

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Alcohol Motor Fuels, Leo M. Christensen, R. M. Hixon, E. I. Fulmer Jan 1934

Alcohol Motor Fuels, Leo M. Christensen, R. M. Hixon, E. I. Fulmer

Proceedings of the Iowa Academy of Science

The proposal to encourage the use of power alcohol made from farm crops grown in the Continental United States, as an aid to agriculture, is not new. Since the last consideration, something more than ten years ago, anhydrous ethyl alcohol has become commercially available. This development makes it feasible to use alcohol-gasoline mixtures. The power alcohol project is thus placed upon a new basis and is worthy of a new consideration.

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