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Binary System With Acetamide: (1) Acetamide - Water (2) Acetamide - Naphthalene, Ben H. Peterson
Binary System With Acetamide: (1) Acetamide - Water (2) Acetamide - Naphthalene, Ben H. Peterson
Proceedings of the Iowa Academy of Science
The binary system acetamide and water, investigated by the solubility method, shows the formation of a hydrate of acetamide of composition (CH3CONH2)2H2O. The system is especially characterized by two solubility curves of acetamide in water, one lying ten to twelve degrees below the other. This is due to the two modifications of pure acetamide, with melting points at 80°C. and 69.4°C. In the more dilute solutions, supercooling can be carried to 80° below the crystalizing temperature in sealed tubes. The Binary System acetamide-naphthalene, investigated by the freezing point method shows two eutectics, …
The Construction And Use Of A Concave Grating Spectrograph, W. C. Oelke, George Montross
The Construction And Use Of A Concave Grating Spectrograph, W. C. Oelke, George Montross
Proceedings of the Iowa Academy of Science
In order to learn some of the fundamentals of analytical spectrography, a concave grating spectrograph was constructed as a cooperative student-faculty project. Details of construction and methods of use were given. Both qualitative and quantitative applications of the instrument are considered.
A Quantitative Spectrographic Study On The Effects Of The Alkali Metals Upon The Determination Of Calcium, Louis Waldbauer, John A. Means
A Quantitative Spectrographic Study On The Effects Of The Alkali Metals Upon The Determination Of Calcium, Louis Waldbauer, John A. Means
Proceedings of the Iowa Academy of Science
It has been known for some time that in spectrographic analysis each element present has some effect upon the other elements present. Our investigation of the effect of the alkali metals on calcium showed that, in general, the intensity of the spectral lines of calcium increased with an increase in the percentage of the alkali metal present. However, there is a decrease in the intensifying effect at the higher concentrations. The chlorides of the alkali metals used were in concentrations varying from 1.0 per cent to 0.031 per cent, and the concentrations of the calcium solutions used varied approximately over …
Freezing Point Curves Of Iodine Monochloride Mixed With Iodine, Acetic Acid, Or Carbon Tetrachloride, Jacob Cornog, Leonard Olson
Freezing Point Curves Of Iodine Monochloride Mixed With Iodine, Acetic Acid, Or Carbon Tetrachloride, Jacob Cornog, Leonard Olson
Proceedings of the Iowa Academy of Science
The curve obtained with iodine differs from the curve obtained by previous workers; the acetic acid curve approximates expectation based on Raoult's Law; the carbon tetrachloride curve indicates the formation of solid substances.
The Solubility Of Ignited Ferric And Chromic Oxides, Jacon Cornog, Dorothy Buck
The Solubility Of Ignited Ferric And Chromic Oxides, Jacon Cornog, Dorothy Buck
Proceedings of the Iowa Academy of Science
In the gravimetric determination of iron the metal is frequently precipitated as the hydroxide by ammonia. It is then collected by filtration, dried, ignited and weighed as the oxide. Such precipitates when wet, as hydroxides, dissolve instantaneously in acids. After the precipitate has been ignited it often becomes practically insoluble. Such ignition gives a range of temperature of 600° - l000°C, depending on the type of heating device used. Kolthoff and Sandell suggest the fusion of this ignited ammonia precipitate with alkali pyrosulfate "in order to convert the oxides into sulfate which then can be dissolved." This procedure is troublesome …
The Effect Of Egg Albumin On The Solubility Of Thallous Salts At 25 C, W. G. Eversole, Carold F. Bjork
The Effect Of Egg Albumin On The Solubility Of Thallous Salts At 25 C, W. G. Eversole, Carold F. Bjork
Proceedings of the Iowa Academy of Science
The solubilities of TlCl, TlCNS, and Tl2SO4, were determined in solutions of egg albumin at 25°C. The Tl+ was titrated to Tl+++ with standard KI03 using the ICl endpoint. The albumin concentration was determined by a modified Kjeldahl method. The pH of each solution was obtained with a glass electrode using M/20 potassium acid phthalate as a standard (pH= 3.97). In solutions of egg albumin dialyzed free of chlorides and sulphates and adjusted to a pH of 3.3 it was found that the greater the albumin concentration the greater was the amount of dissolved salt …
Further Evidence Of A New Factor In The B Complex, W. R. Wyatt, V. E. Nelson
Further Evidence Of A New Factor In The B Complex, W. R. Wyatt, V. E. Nelson
Proceedings of the Iowa Academy of Science
The vitamin B complex is generally accepted as containing at least five distinct components for the rat; B1 (thiamin), flavin, nicotinic acid, B6, and the filtrate factor. Work by Jukes and Babcock (1) and by Oleson and co-workers (2) indicates that a distinct antiparalytic factor (very likely Reader's "B4") exists. Stocks tad (3) has reported a growth factor "U" for the chick. One of the authors (4) has given evidence of the existence of still another factor, the "8B factor," in the B complex. That chondroitin sulfuric acid is a growth factor for the rat …
Some Applications Of Chemistry To The Manufacture Of Dairy Products, E. W. Bird
Some Applications Of Chemistry To The Manufacture Of Dairy Products, E. W. Bird
Proceedings of the Iowa Academy of Science
This discussion is in no way intended as an inclusive one relative to the application of chemistry to the dairy industry. It is intended rather as a brief resume of certain problems that have been studied, at least in part, by the Dairy Industry Section of the Iowa Agricultural Experiment Station. For ease of handling and for continuity the subjects might, without too great a stretch of imagination, he classed as applications of analytical chemistry, catalysis, surface chemistry, physical chemistry and enzyme chemistry to the manufacture of dairy products. Two analytical chemical problems will be considered here, (1) Why is …
Ring Compunds From Chloroamines And Amides, George H. Coleman
Ring Compunds From Chloroamines And Amides, George H. Coleman
Proceedings of the Iowa Academy of Science
Substituted pyrrolidines have been prepared in good yields by heating N-chlorine derivatives of secondary amines with a mixture of sulfuric acid and water. Amines such as methyl-n-butylamine, ethyl-n-butylamine, methyl-n-amylamine, and di-n-butyl amine have been used. The optimal conditions for ring closure are not the same for all amines. Varying amounts of secondary amines are usually recovered. In this reaction an intermediate compound is formed with sulfuric acid. The compound from N-chloro-di-n-butylamine has been isolated as a white solid and analyzed. With N-chloro-N-methyl-n-octylamine ring closure apparently occurs with the fifth carbon from nitrogen to form a substituted piperidine. However, complete identification …
Preparation And Some Properties Of Isomeric Carboaryloxyaminoanilines, L. Chas. Raiford, Williiam Homer Coppock
Preparation And Some Properties Of Isomeric Carboaryloxyaminoanilines, L. Chas. Raiford, Williiam Homer Coppock
Proceedings of the Iowa Academy of Science
Heating 2-aminophenylurethane above its melting point causes loss of alcohol and formation of o-phenyleneurea [Ber., 12, 1296 ( 1879)]. Attempts to acylate the hydroxyl group of 2-carbophenoxyaminophenol splits off phenol and closes the benzoxazolone ring [J. Am. Chem. Soc., 56, 1590 (1934)], as shown below. It is now found that when 2-carliophenoxyaminoaniline is heated above its melting point phenol is lost and o-phenyleneurea is formed. If the same aminoaniline derivative is dissolved in caustic alkali solution and the resulting liquid is acidified with dilute mineral acid the cyclic urea indicated above is precipitated. The formation of this urea is favored …
Fossil Plants Of A Des Moines Sandstone Cave Deposit Near Robins, Linn County, Iowa, L. R. Wilson, A. T. Cross
Fossil Plants Of A Des Moines Sandstone Cave Deposit Near Robins, Linn County, Iowa, L. R. Wilson, A. T. Cross
Proceedings of the Iowa Academy of Science
A Des Moines sandstone cave deposit in Lower Davenport limestone was, until recently, exposed in a quarry one-half mile northeast of Robins, Linn County, Iowa. The quarry is in the Northeast Quarter of Section 22, Township 48 North, Range 7 West. The rock containing the plant fossils is a medium to fine grained, buff sandstone that was about 32 feet wide with a maximum thickness of 18 inches when examined in January, 1938. Since then, recent quarrying operations have completely removed the deposit. Plant material was abundant through the deposit but very fragmental. The larger fragments are highly ferruginated or …
Upper Pennsylvanian Section In Western Adams County, Iowa, Lyman W. Wood
Upper Pennsylvanian Section In Western Adams County, Iowa, Lyman W. Wood
Proceedings of the Iowa Academy of Science
Preparation of a report by the writer on the "Geology of Adams County" for the Iowa Geological Survey has required a more complete field study of coal mine shaft sections and natural exposures in the west part of the county than had hitherto been made. This field study has brought out interesting details of the beds above the Nodaway coal seam not reported in previous literature. The purpose of this paper is to present the section observed.
Fossils Of The Peorian Loess In Iowa, Cornelia Cameron
Fossils Of The Peorian Loess In Iowa, Cornelia Cameron
Proceedings of the Iowa Academy of Science
The fossils of representative sections of Peorian loess in Iowa have been examined in detail for the purpose of determining the conditions under which the loess was deposited. In most cases samples were collected at six inch intervals. The shells, pulmonate gastropods, were washed, identified, and charted in order of their vertical occurrence. The majority of species have equivalent modern forms whose habitats are known. Assuming that their mode of living was approximately the same as in the period of loess deposition, ecological conclusions may be drawn. Each section gives a history of local change of moist and dry conditions …
Unconformity At The Base Of The Henrietta Group In Iowa, L. M. Cline
Unconformity At The Base Of The Henrietta Group In Iowa, L. M. Cline
Proceedings of the Iowa Academy of Science
In Missouri the base of the Henrietta group is drawn at the base of the Lower Fort Scott limestone. This thin but persistent limestone is easily recognized in the field and can be identified in many well sections in northern Missouri and in Iowa. 'While the Lower Fort Scott limestone may form the most practical boundary for the Henrietta in Iowa, it does not form the most natural lower limit of this group. After deposition of the Bevier coal and prior to the deposition of the Mulky coal there was a period of uplift and widespread channeling. Locally, as in …
Permian Ammonoid Zones, A. K. Miller, W. M. Furnish
Permian Ammonoid Zones, A. K. Miller, W. M. Furnish
Proceedings of the Iowa Academy of Science
Ammonoids are among the best of index fossils and are particularly useful for intercontinental correlations. Five major ammonoid zones are recognized in the Permian, all of which are of world-wide significance. In Texas and northern Mexico the Permian is particularly well developed and is abundantly fossiliferous, and the section in this area serves well as a standard for the rest of the world.
Origin Of Analcite In Igneous Rocks Of The Terlingua District, Texas, John T. Lonsdale
Origin Of Analcite In Igneous Rocks Of The Terlingua District, Texas, John T. Lonsdale
Proceedings of the Iowa Academy of Science
Many of the igneous rocks of the Terlingua district in west Texas contain analcite as an important mineral. The analcite-bearing rocks generally are assemblages of andesine or labradorite, alkali feldspar, augite or aegirite-augite, olivine, iron ores, and analcite. Biotite is present in some types but absent in others. Important types are analcite syenogabbro, analcite trachybasalt porphyry, analcite trachycdolerite, and analcite syenite. Analcite was formed in these rocks through an extended period from late magmatic to definitely post magmatic stages. Reaction between the analcitic liquid and earlier formed minerals resulted in a series of reaction products including analcite aegirite-augite, serpentine, albite, …
Missouri Equivalent Of Cedar Valley Limestone, Charles Keyes
Missouri Equivalent Of Cedar Valley Limestone, Charles Keyes
Proceedings of the Iowa Academy of Science
When Louis Agassiz delivered, at the University of Iowa, in 1867, his now famous lectures on Ancient Coral Reefs, he selected for his main theme the great coral reef upon which Iowa City was built. Reputation of Iowa's great Coral Reef was established. This reef was, as we now know, the main median body of Owen's Cedar Valley limestone. Now this great coral reef appears not to extend very far south of Iowa City, and seems to be altogether unrepresented in Missouri. Inasmuch as in Missouri the Cooper limestone appears to be the equivalent of the Wapsipinicon limestone of Iowa, …
Thermal Stresses In An Isosceles Right-Tri-Angular Plate With Pinned Edges, D. L. Holl
Thermal Stresses In An Isosceles Right-Tri-Angular Plate With Pinned Edges, D. L. Holl
Proceedings of the Iowa Academy of Science
The object of this paper is two-fold: (1) to show that in certain cases of simply supported plates, the problem of thermal stresses due to unequal surface temperatures is equivalent to a membrane problem under normal surface pressure; and (2) to give some results for an isosceles right-triangular plate.
High Voltage Apparatus For Nuclear Physics, A. Ellett, R. D. Huntoon, D. S. Bayley, J. A. Van Allen, V. J. Young
High Voltage Apparatus For Nuclear Physics, A. Ellett, R. D. Huntoon, D. S. Bayley, J. A. Van Allen, V. J. Young
Proceedings of the Iowa Academy of Science
The design and performance of a transformer-rectifier voltage quadrupling installation for potentials up to 600 KV will be described.
A Deuterium - Deuterium Source Of Neutrons, Victor Young
A Deuterium - Deuterium Source Of Neutrons, Victor Young
Proceedings of the Iowa Academy of Science
A single section accelerator tube built for 300 to 400 k.v. is used to accelerate a beam of deutrons obtained from a conventional arc discharge source. The beam impinges on a target of P2O5 + H22O producing neutrons according to the reaction H2+H2=H3+n. The target assembly is immersed in a tank of water which because of the elastic H1 and n collisions becomes a source of thermal neutrons. Detection is accomplished by placing a piece of silver in the tank. The silver becomes artificially beta radioactive by …
The Desensitization Of Photographic Emulsions By Various Agents At Different Wavelengths Of Light, Homer Mouden
The Desensitization Of Photographic Emulsions By Various Agents At Different Wavelengths Of Light, Homer Mouden
Proceedings of the Iowa Academy of Science
A study of the effectiveness of the organic compounds Pinakryptol yellow, Pinakryptol green, Phenosafranine, and Safranine as desensitizers for photographic emulsions; and the effect of the desensitizers to different wavelengths of light as obtained by exposure through the Wratten filters numbers 78, 58, 47, and 25.
Studies Of Dielectric Liquid Mixtures, Cleo C. Byers, Arthur F. Vetter
Studies Of Dielectric Liquid Mixtures, Cleo C. Byers, Arthur F. Vetter
Proceedings of the Iowa Academy of Science
An experimental study of the continuous variation of the low frequency dielectric constant and the optical refractive index of binary mixtures of certain liquid dielectrics with varying concentration. Special condenser and refractometer methods are used, respectively, by the two authors.
Present Role Of Ultrasonic Waves In Physics, Victor B. Corey
Present Role Of Ultrasonic Waves In Physics, Victor B. Corey
Proceedings of the Iowa Academy of Science
The following are the significant results of modern researches in ultrasonics with regard to their contributions to theoretical and applied physics. Precision velocity measurements in gases, made over wide frequency ranges by means of the Pierce interferometer serve experimentally to substantiate the kinetic theory of gases; such measurements in liquids, made either by the interferometer, diffraction spectra, or visibility method, offer an independent and exact means for calculation of important physical constants of the liquids, and through detection of velocity dispersion, suggest a point of attack for investigation of liquid structure. Sound field amplitude photographs afford precise measurements of ultrasonic …
A Comparison Of Personality Adjustment Scores Of Rural And Urban Children In Ninth Grade, A. Elizabeth Beal
A Comparison Of Personality Adjustment Scores Of Rural And Urban Children In Ninth Grade, A. Elizabeth Beal
Proceedings of the Iowa Academy of Science
A large number of studies of differences between urban and rural groups have been made. Many have studied the intelligence and achievement of town and rural pupils. (1) However, relatively few have used modern standardized tests of personality and social attitudes. (2) Teachers have often been conscious of the fact that many rural pupils seem more retiring, shy, and ill-at-ease, especially during their early days in the new school. Others have said that they noticed no such differences, or that with all the 4-H work, better transportation and schools, and frequent contacts with town conditions, for rural people, differences such …
The Iowa State Student Adjustment Inventory: A Filial Relations Scale For Personal Procedures, Earle E. Emme, Lyle K. Henry
The Iowa State Student Adjustment Inventory: A Filial Relations Scale For Personal Procedures, Earle E. Emme, Lyle K. Henry
Proceedings of the Iowa Academy of Science
This is the third of a series of papers on the Filial Affection Inventory to be presented to the Iowa Academy of Science. Two years ago the reader (Dr. Emme) reported how the scale was constructed and how it could be used as a tool in personnel work. 1 Last year, Henry made a validation study in which he compared the scale to the home adjustment section of the Bell Adjustment Inventory. 2 The purpose of the present paper is to present the type of data which may he obtained when the inventory is administered to groups of students. Further …
A Comparative Study Of The A.C.E. Test And The Iowa Silent Reading Test, Orpha Sherman
A Comparative Study Of The A.C.E. Test And The Iowa Silent Reading Test, Orpha Sherman
Proceedings of the Iowa Academy of Science
The purpose of this investigation is to study the relative effectiveness of the 1938 form of the American Council on Education Psychological Examination and the Iowa Silent Reading Test in predicting the success of freshmen during their first semester in college.
Frequency Of Serious Visual Defects, Edith Burma, A. R. Lauer
Frequency Of Serious Visual Defects, Edith Burma, A. R. Lauer
Proceedings of the Iowa Academy of Science
Many practitioners have thousands of cards in their patient files which might be used to determine the visual conditions of clinical patients when they appear for examination. From the standpoint of the motor vehicle administrator, two other problems exist. One treats of what the practitioner would find if he were to examine a random sampling of the population to ascertain the extent of visual defects, using regular clinical methods. The other deals with the percentage of defects which a trained examiner giving regular driver’s license examinations might find in a non-clinical population. By non-clinical we mean a sampling of the …
The Problems And Interests Of High School And College Students, Owen Haffner, Donald Schild
The Problems And Interests Of High School And College Students, Owen Haffner, Donald Schild
Proceedings of the Iowa Academy of Science
The purpose of this study was to determine the concerns of interest and the personal problems of high school and college students. The problem was conducted in connection with a course in the psychology of motivation, at Iowa State College. The functional approach in education is receiving much emphasis at the present. If the work of the school can relate itself to the needs and interests of the students, its effectiveness can be greatly increased. Studies such as the present one are thought to be of value in considering curricular offerings of high schools and colleges. The procedure for the …
Analysis Of Difficulties In Reading And Learning To Read, Bena K. Hansen
Analysis Of Difficulties In Reading And Learning To Read, Bena K. Hansen
Proceedings of the Iowa Academy of Science
Probably one of the most difficult of mental tasks undertaken by human beings is one that must be begun by the child at five to "even years of age. If the tools with which he works at this task, namely, learning to read, are not up to par, his reading will be carried on in a defective manner or may not even be achieved at all. Bad habits of attacking this task may also handicap the child in learning to read. Inability to read with some degree of efficiency is the cause of failure in school and conflicts in both …
An Experiment In Transfer Of Training, Ruth B. Mcdonald
An Experiment In Transfer Of Training, Ruth B. Mcdonald
Proceedings of the Iowa Academy of Science
Much work has been done on the transfer of training in experiments of perception and motor skills, and some studies have been made using school subject matter. The idea of formal discipline upon which some of the work in the schools has been based, has given way to the more modern phenomenon of transfer. Many of the studies carried on demonstrated transfer effects averaging from 20 to 30 per cent. The present study has to do with the simple sensori-motor skill of card sorting. It was assumed at the beginning of the experiment that negative transfer would be noted. The …