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Articles 78001 - 78030 of 78507
Full-Text Articles in Entire DC Network
Control Of Pocket Gophers, Maynard W. Cummings
Control Of Pocket Gophers, Maynard W. Cummings
Vertebrate Pest Conference Proceedings: 1st (1962)
Pocket gophers occur only in North and Central America but within this vast area few other native rodent groups are more widely distributed (Anthony, 1928). None are more adaptable, either to natural extremes of habitat or to changed conditions brought about by agricultural development and other man-made environmental modifications. They occupy coastal areas, inland plains and valleys, desert and alpine meadow, from sea level to above timber line in a multitude of vegetation and soil types. This practically universal distribution has, of course, led to the recognition by naturalists of many species and subspecies. California alone contains at least 75 …
Control Methods For Snakes, Elbert M. Brock, Walter E. Howard
Control Methods For Snakes, Elbert M. Brock, Walter E. Howard
Vertebrate Pest Conference Proceedings: 1st (1962)
Of the various types of wildlife that home owners find undesirable, snakes are probably the leading offenders. Because of much false teaching, many persons have a great dread of even non-venomous snakes; hence control often is practiced when not needed. Nevertheless, very few people are willing to accept the presence of snakes in their gardens or their yards, especially if there is a concern for children playing in the area. For this reason snake control is often desirable about homes and suburban housing areas. Other situations where controls might be justified are recreation areas, farms, bird sanctuaries, duck nesting marshes, …
The Synthesis And Medicinal Chemical Study Of Some Pyridazones, Winnifred M. Osner
The Synthesis And Medicinal Chemical Study Of Some Pyridazones, Winnifred M. Osner
Chemistry and Chemical Biology ETDs
An examination of the literature revealed that the majority of pyridazines prepared were substituted in the three and six positions. Therefore, it appeared appropriate to prepare four and five substituted pyridazines.
The Gascoyne River Catchment Area, W M. Nunn
The Gascoyne River Catchment Area, W M. Nunn
Journal of the Department of Agriculture, Western Australia, Series 4
A RECENT Department of Agriculture survey of the Gascoyne River catchment area has indicated that deterioration of plant cover in the area contributes to the severity of floods which regularly damage the town of Carnarvon.
It is hoped that the results of the survey will help efforts to regenerate the catchment area, and reduce the risk of flooding.
A Survey Of The Waters Of The Cache National Forest, Utah, C.J. D. Brown
A Survey Of The Waters Of The Cache National Forest, Utah, C.J. D. Brown
Elusive Documents
No abstract provided.
A Middle Miocene Rhinoceros Quarry In Morrill County, Nebraska (With Notes On Hip Disease In Diceratherium), Robert M. Stecher, C. Bertrand Schultz, Lloyd G. Tanner
A Middle Miocene Rhinoceros Quarry In Morrill County, Nebraska (With Notes On Hip Disease In Diceratherium), Robert M. Stecher, C. Bertrand Schultz, Lloyd G. Tanner
Bulletin of the University of Nebraska State Museum (1924–2023)
Extensive deposits of fossil rhinoceros bones have been excavated from University of Nebraska State Museum collecting localities Mo-113, -114, -115, -116, and -118 some 8 1/2 to 9 1/2 miles north of Bridgeport, Morrill County, Nebraska. The fossils were associated with other faunal elements in the lower portion of the Marsland formation (middle Miocene) of the Hemingford group. The rhinoceros is considered to be Diceratherium niobrarensis Peterson, geologic variety. A pathologic right femur of D. niobrarensis provides evidence of hip disease in the medial Miocene rhinoceroses.
Early Records Of Some Mammals From Nebraska, J. Knox Jones Jr.
Early Records Of Some Mammals From Nebraska, J. Knox Jones Jr.
Bulletin of the University of Nebraska State Museum (1924–2023)
Ten species of Recent mammals that formerly occurred in Nebraska have been extirpated there by European man. Surprisingly few specimens of the species concerned are preserved in museum collections. Perusal of a representative segment of the historical literature pertaining to Nebraska has revealed records of occurrence of most of the extirpated species that provide a basis for estimating the former distribution of each in the State.
Studies Involving Modification Of The Megregian Method Of Fluoride Determination And Application To Fluoride Balance Studies In Infants, Gene R. Wright
Studies Involving Modification Of The Megregian Method Of Fluoride Determination And Application To Fluoride Balance Studies In Infants, Gene R. Wright
Masters Theses
Introduction
At the request of Dr. Frederick Margolis, M.D., and in association with The Upjohn Company, this research problem was initiated as a participation in the investigation of whether or not fluoride ingested as a constituent of the Upjohn 47-M liquid vitamin preparation is retained in an infant's body to the same extent as is fluoride ingested as the sodium salt by itself--either in solution or in tablet form. The retention patterns may be studied indirectly by measuring the amounts of fluoride excreted in the urine and in the feces during each of a series of equal time intervals after …
Growth Study Of Young Gizzard Shad, George Pahl, Gordon Willfahrt
Growth Study Of Young Gizzard Shad, George Pahl, Gordon Willfahrt
Journal of the Minnesota Academy of Science
This investigation was part of a general study aimed at shedding light upon the role of the gizzard shad (Dorosoma cepedianum) as a forage fish of certain game fish species. Recent changes in the populations of such game fish species as the walleye ( Stizastedion vitreum), northern pike ( Esox lucius) , and largemouth bass (Micropterus salmoides) in the upper Mississippi River suggest that the gizzard shad population might have an important bearing on the present situation. The purpose of this investigation was to study the growth rates of the gizzard shad in the Upper Mississippi River during their first …
Investment Theory And Forest Management Planning, Barney Dowdle
Investment Theory And Forest Management Planning, Barney Dowdle
Yale School of the Environment Bulletin Series
No abstract provided.
Geological Implications Of Soil Mechanics, James Harrison Quinn
Geological Implications Of Soil Mechanics, James Harrison Quinn
Journal of the Arkansas Academy of Science
No abstract provided.
A Study Of The Behavior Of Zirconium In Aqueous Solutions And The Separation Of Radioactive Zirconium By Electrodialysis, Charles William Brauer Jr.
A Study Of The Behavior Of Zirconium In Aqueous Solutions And The Separation Of Radioactive Zirconium By Electrodialysis, Charles William Brauer Jr.
Masters Theses
"Nuclear reactor installations designed for power production must of necessity operate at higher energy levels than their experimental precursors. As these facilities increase in number, better solutions must be found for both technical and economic problems.
The disposal of waste materials is of primary importance and will require greater effort if satisfactory disposal methods are to keep pace with the increase of waste materials, produced by the increasing number of new nuclear facilities. The radioactive materials present in this waste material may constitute a valuable by-product from these operations if suitable and economic recovery procedures are developed. If the development …
Electron Transport Particles From Bacillus Stearothermophilus, Ronald J. Downey, Carl E. Georgi, Walter E. Militzer
Electron Transport Particles From Bacillus Stearothermophilus, Ronald J. Downey, Carl E. Georgi, Walter E. Militzer
Department of Chemistry: Faculty Publications
DOWNEY, RONALD J. (University of Nebraska, Lincoln), CARL E. GEORGI, AND WALTER E. MILITZER. Electron transport particles from Bacillus stearothermophilus. J. Bacteriol. 83:1140- 1146. 1962-Electron-transport particles (ETP) have been isolated from Bacillus stearothermophilus. They are capable of oxidizing such substrates as succinate, malate, diphosphopyridine nucleotide, p-phenylenediamine, and hydroquinone. Difference spectra indicated bands of cytochromes a3, b, and c. A chromatographic procedure for purification of cytochrome c has been described. The role of quinonelike intermediates in the ETP was implied by the restorative effect of coenzyme Q and vitamin K1 on material treated …
A New Approach To General Chemistry Laboratory In College (With) A Laboratory Manual For General Chemistry, Constantine G. Vlassis
A New Approach To General Chemistry Laboratory In College (With) A Laboratory Manual For General Chemistry, Constantine G. Vlassis
University of the Pacific Theses and Dissertations
Statement of the problem. This study was carried out to determine: (1) what advantages a laboratory-centered general chemistry course might have over the conventional laboratory course, and (2) whether improved understanding of laboratory work leads to better learning of chemistry. The four following questions were raised in connection with the study or this problem:
- What is the need for a laboratory-centered course?
- What has been done in the past to meet this need?
- Can students learn chemistry more effectively in a laboratory-centered course as compared to the conventional course?
- Is a laboratory-centered course to be preferred over the conventional course …
A Laboratory-Centered General Chemistry Course For College Freshmen, Alexander Vavoulis
A Laboratory-Centered General Chemistry Course For College Freshmen, Alexander Vavoulis
University of the Pacific Theses and Dissertations
In order to give the laboratory-centered course a trial run and to compare it with a lecture-centered course it seemed necessary to the author that both courses should be taught and compared. The latter gave rise to the following hypotheses:
- Students in a laboratory-centered general chemistry course show more favorable attitudes toward chemistry than do students in a lecture-centered course.
- Students in a laboratory-centered course show as good a subject-matter mastery as students in a lecture-centered course.
The Influence Of Temperature And Some Other Factors On The Biological And Nonbiological Oxidation Of Chalcopyrite, Pyrite And Copper Sulfide, Ezra Revier Palmer
The Influence Of Temperature And Some Other Factors On The Biological And Nonbiological Oxidation Of Chalcopyrite, Pyrite And Copper Sulfide, Ezra Revier Palmer
Theses and Dissertations
The purpose of this study was: (1) to find the effect of temperature on the wet oxidation of chalcopyrite, pyrite, and copper sulfide over the biological and nonbiological range; (2) to determine the influence of ferrous and ferric iron and free oxygen(air) on the oxidation. The sulfide minerals studied were oxidized over a range of temperatures between 25° to 75° C. The optimum biological oxidation occurred near 35° C. The nonbiological oxidation was very slow at low temperatures but increased with increasing temperature. The effect of solutions used in leaching the various sulfides over the temperature range differred. A synthetic …
An Investigation Of The Isotopic Exchange Of Arsenic Atoms Between Arsenic(Iii) And Arsenic(V) In Aqueous Hydrochloric Acid Solutions, Lewis L. Anderson
An Investigation Of The Isotopic Exchange Of Arsenic Atoms Between Arsenic(Iii) And Arsenic(V) In Aqueous Hydrochloric Acid Solutions, Lewis L. Anderson
Chemistry and Chemical Biology ETDs
An isotopic exchange reaction is a chemical reaction in which atoms of a given element interchange between two or more chemical forms of the element. A homogeneous stable system is one in which all reactants are in chemical equilibrium and distributed uniformly throughout a single phase. An example of isotopic exchange is the interchange of iodine atoms between iodide ions and ethyl iodide, where the asterisk indicates radioactive atoms of iodine.
Phase Equilibria In Fused Salt Systems: Binary Systems Of Plutonium(Iii) Chloride With The Chlorides Of Magnesium, Calcium Strontium, And Barium, Karl W. R. Johnson
Phase Equilibria In Fused Salt Systems: Binary Systems Of Plutonium(Iii) Chloride With The Chlorides Of Magnesium, Calcium Strontium, And Barium, Karl W. R. Johnson
Chemistry and Chemical Biology ETDs
Fused salt systems containing oxides have received the most attention to date, because of their occurrence in minerals and ores and their application to ceramics. The next most widely studied of group of compounds are the metal halides, particularly the metal chlorides. Despite the fact that many of the metal chlorides are hygroscopic, the salts lend themselves to experimentation because a large majority undergo stable solid-liquid transformations below 1000 degrees C, are generally ionic, and are relatively non-corrosive.
Experimental Studies Of The Visible Absorption Spectrum Of Titanium (Iii) Acetylacetonate In Solutions And Rigid Glasses, Arthur L. Langhorst Jr.
Experimental Studies Of The Visible Absorption Spectrum Of Titanium (Iii) Acetylacetonate In Solutions And Rigid Glasses, Arthur L. Langhorst Jr.
Chemistry and Chemical Biology ETDs
Titanium (III) acetylacetonate was synthesized and the visible absorption spectrum was measured. A prominent absorption band, ymax at approximately 6000 was found with molar absorption coefficient of ~1000. The spectrum was investigated at temperatures ranging from 25 degrees C to 77 degrees K. At 7 7 degrees K the band was resolved into five well defined peaks at 4750, 5100, 5520, 5950 and 6460. An apparatus for obtaining spectrophotometric measurements of solution and rigid glasses was designed and fabricated.
The Synthesis Of Potential Antitumor Compounds, Duane L. Aldous
The Synthesis Of Potential Antitumor Compounds, Duane L. Aldous
Chemistry and Chemical Biology ETDs
The antitumor activity found in such ring systems as the purine, pyrazolo [3,4-d] pyrimidine, and the 8-azapurine prompted the preparation of the imidazo [4,5-d] pyridazine ring system. Castle and Seese were one of the first to study this ring system. 4-Aminoimidazo[4,5-d]pyridazine possessed some anitumor activity. This antitumor activity suggested the preparation of the 4,7-disubstituted-aminoimidazo{4,5-d]pyridazines reported here. The antileukemic activity reported for 6-purinethiol led to the synthesis of several 4- and/or 7-mono-and disubstitutedthioimidazo[4,5-d]pyridazines.
Spectroscopic Studies Of The Luminescences Of Rare Earth Chelates, Ruth Elaine Whan
Spectroscopic Studies Of The Luminescences Of Rare Earth Chelates, Ruth Elaine Whan
Chemistry and Chemical Biology ETDs
A variety of lanthanide chelates were prepared for preliminary luminescence studies under excitation by ultraviolet light. From these, chelates of benzoylacetone, dibenzoylmethane, tribenzoylmethane, and 8-hydroxyquinoline were selected for more extensive investigation. Energies of the lowest excited singlet and triplet states of the chelates were determined. Average values of 24,500 cm-1 and 20,500 cm-1 respectively were obtained for the dibenzoylmethides and 24,400 cm-1 and 21,450 cm-1 for the benzoylacetonates. Only small variations of a few hundred wavenumbers in the positions of the excited states were found as the chelated ion was varied. This investigation in conjunction with …
The Influence Of Temperature On The Impedance To Water Flow Through Plants, Royal Duane Jensen
The Influence Of Temperature On The Impedance To Water Flow Through Plants, Royal Duane Jensen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This era has been termed the atomic or space age. The greatest concern of most people seems to be centered around survival from the destruction and suffering that might be caused by atomic and nuclear weapons. However, along with this, the world is confronted with perhaps a greater disaster--a potential calamity seldom realized by most people, yet a problem which grows more serious in the world each year--a tragedy which would probably be worse than destruction from nuclear weapons. This encroaching catastrophe is starvation.
Even today the majority of the people in the world do not have enough food. Each …
The Effects Of Certain Environmental And Biological Factors On Rally Calling In The Chukar Partridge, H. Warrington Williams
The Effects Of Certain Environmental And Biological Factors On Rally Calling In The Chukar Partridge, H. Warrington Williams
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Naturalists for many years have known that birds sing most at dawn and at dusk, but to which of many physical variables they are responding has not been completely determined. This problem has taken on importance in the field of wildlife management because calling rate has been used as an index of abundance for numerous game birds, namely the Pheasant, Phasianus colchicus (Kimball, 1949); the Mourning Dove, Zenaidura macroura (McClure, 1939); the Bobwhite Quail, Colinus virginianus (Bennitt, 1951; Rosene, 1957): and the Woodcock, Philohela minor (Pitelka, 1943).
Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice
Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen has commonly been a deficient element in the cultivated soils of the world since the beginning of agriculture. The general acceptance of the practice of using manures as a means of increasing plant growth, as shown by the records of ancient civilizations, attest to this fact. Since the time of von Liebig there has been an increasing awareness of the importance of this deficiency in soils. As a result of a better understanding of the problem and the increasing availability of commercial forms of nitrogen, a rapid increase in the use of nitrogen fertilizers has taken place in the …
The Effect Of Temperature And Moisture On Nitrification Of Applied Ammoniacal Fertilizer In A Noncalcareous Soil, Merwin Allen Stevens
The Effect Of Temperature And Moisture On Nitrification Of Applied Ammoniacal Fertilizer In A Noncalcareous Soil, Merwin Allen Stevens
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The importance of nitrogen in world agriculture has been known for many years. But in the past few decades the enormity of the problem of nitrogen economy has been recognized. Along with the recognition of this problem there has developed a great increase in the use of nitrogen fertilizers. Coupled with the increased use of nitrogen there has come about an increasing awareness of the problem involved in the use of nitrogen fertilizers.
The Seventy-Third Session Of The Iowa Academy Of Science And The Twenty-Ninth Convention Of The Iowa Junior Academy Of Science, April 14-15, 1961, Iowa Academy Of Science
The Seventy-Third Session Of The Iowa Academy Of Science And The Twenty-Ninth Convention Of The Iowa Junior Academy Of Science, April 14-15, 1961, Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
Polysubstituted Piperazinethiocarboxamides, Donald W. Kreh
Polysubstituted Piperazinethiocarboxamides, Donald W. Kreh
Master's Theses
Thiourea and its derivatives have found wide application in dyes, photographic film, elastomers, plastics and textiles. Certain thioureas possess biological properties and considerable work has been done in this area. The historical portion of this paper is divided into biological and non-biological properties of thioureas. In the literature search, primary importance was given to the biological properties of thioureas. The objective of the experimental work was to prepare compounds having potential pharmacological activity and to determine the physical constants of these compounds.
Determination Of A Molecular Weight Distribution For Intermediate Degradation Products Of Bovine Plasma Albumin, Sherwin M. Beck
Determination Of A Molecular Weight Distribution For Intermediate Degradation Products Of Bovine Plasma Albumin, Sherwin M. Beck
Master's Theses
Within the last decade several important studies have been made on the large degradation of products of proteins. However, little work has been done on the intermediate degradation products. This study is concerned with the chromatographic separation of intermediate fragments from chrymotryptie hydrolysates of bovine plasma albumin and the determination of the molecular weights of the fragments. An automatic recording differential refractometer employing a differential cell of original design permitted the observation of chromatographic components as they were eluted f rom a column of Sephadex G-50. A fraction collector of original design collected 3 ml. fractions of the effluent. Three …
The Control Of Grasses With Chemicals, G R W Meadly
The Control Of Grasses With Chemicals, G R W Meadly
Journal of the Department of Agriculture, Western Australia, Series 4
GRASSES are among man's greatest assets and usually he tries to encourage their growth.
The cereals, rice and many other grasses supply him with basic items of food and they are also important components of pastures which provide grazing for sheep and cattle.
Palatability Of Forage Plants In North-West Sheep Pastures, R H. Collett
Palatability Of Forage Plants In North-West Sheep Pastures, R H. Collett
Journal of the Department of Agriculture, Western Australia, Series 4
A DECLINE in carrying capacity has occurred in large areas of the Pilbara district of the North-West, due to the decrease in palatable plants and the increase in unpalatable ones.
The relative palatability of the various species to sheep is therefore a matter of considerable importance to pastoralists.