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The Effect Of Organic Solvents On The Sensitivity Of Rare Earths Atomic Absorption, Keith A. Geiken Jan 1973

The Effect Of Organic Solvents On The Sensitivity Of Rare Earths Atomic Absorption, Keith A. Geiken

Dissertations and Theses @ UNI

Atomic absorption of the rare earths erbium, europium, and dysprosium was studied in 10% organic solvent-water systems, water miscible solvent-water systems, and in 100% solvent solutions of the metal acetylacetonates. Sensitivity was found to depend on the solvent system used and instrument parameters. All solvent systems used enhanced absorption, with (1) higher number of carbon atoms, (2) tertiary and secondary alcohols, and (3) high boiling point solvents producing the largest increase in absorption. No significant viscosity relationships existed in the 10% solvent-water systems for either miscible or partially soluble solvents; however, viscosity might have been a factor in absorption in …


Glacial Deposits, Vol. 1, 1972-1973, Department Of Geography-Geology Jan 1973

Glacial Deposits, Vol. 1, 1972-1973, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Anionic Polymerization Of A Series Of 5-Membered Cyclocarbosiloxanes, Balaraman Suryanarayanan Jan 1973

Anionic Polymerization Of A Series Of 5-Membered Cyclocarbosiloxanes, Balaraman Suryanarayanan

Doctoral Dissertations

"A study has been made on the anionic polymerization of a series of 5-membered cyclocarbosiloxanes with methyl and/or phenyl substituents. The polymerization was initiated by lithium n-butyldiphenylsilanolate in the presence of tetrahydrofuran. Six 5-membered cyclocarbosiloxanes (2,2,5,5-tetramethyl-1-oxa-2,5-disilacyclopentane; 2,2,5- trimethyl-5-phenyl-1-oxa-2,5-disilacyclopentane; 2,5-dimethyl-2,5-diphenyl- 1-oxa-2,5-disilacyclopentane; 2,2-dimethyl-5 ·,5-diphenyl-1-oxa- 2,5-disilacyclopentane; 2-methyl-2,5,5-triphenyl-1-oxa-2,5-disilacyclopentane; 2,2,5,5-tetraphenyl-1-oxa-2,5-disilacyclopentane) were synthesized. Since the chemical shifts of the protons of the cyclic monomers and the polymers formed were different, the rate of polymerization of the cyclic monomers was measured utilizing an NMR spectrometer. The effects of tetrahydrofuran concentration, initiator concentration and water concentration on the rate of polymer formation and on the molecular weight of …


Ii Popolamento Di Ragni Nelle Grotte Tropicali (Araneae), Paolo Marcello Brignoli Jan 1973

Ii Popolamento Di Ragni Nelle Grotte Tropicali (Araneae), Paolo Marcello Brignoli

International Journal of Speleology

The so called “tropical” caves (most of which are also geographically “tropical”) are distinguished from the “temperate” caves by the much larger trophic resources. Spiders are common in both kinds of caves, but the groups present in one kind are mostly absent in the other (notwithstanding that many families are distributed over at least one temperate and one tropical region). As in all temperate caves more or less the same groups of spiders can be found, so the tropical caves have a typical spider fauna, composed of different groups (often also more than those present in the temperate caves). In …


Aspetti Ecologici Ed Evolutivi Del Popolamento Di Grotte Temperate E Tropicali: Osservazioni Sul Ciclo Biologico Di Alcune Specie Di Ptomaphagus (Coleoptera Catopidae), Valerio Sbordoni, Marina Cobolli-Sbordoni Jan 1973

Aspetti Ecologici Ed Evolutivi Del Popolamento Di Grotte Temperate E Tropicali: Osservazioni Sul Ciclo Biologico Di Alcune Specie Di Ptomaphagus (Coleoptera Catopidae), Valerio Sbordoni, Marina Cobolli-Sbordoni

International Journal of Speleology

Differences between tropical and temperate cave communities are an important topic in the actual biospeleological thinking. Among the most striking differences is the paucity of terrestrial troglobites in tropical caves. This fact may depend on the higher energy input into tropical caves which lessens the selection pressures for energy-economizing troglobite adaptations. Consequently evolutionary rates would be slowed in tropical caves and, in a date group, troglobites would appear later in such caves than in temperate ones with lower energy input. In order to investigate this point the authors studied the degree of adaptation to the cave environment in two species …


Acidities In Ethanol/Water Solvents: The Pka Of Hf, Raymond M. Merrill Dec 1972

Acidities In Ethanol/Water Solvents: The Pka Of Hf, Raymond M. Merrill

Chemistry and Chemical Biology ETDs

The acidity of hydrofluoric acid in mixed ethanol/ water solvent systems was studied by determining the pKa of HF in a number of different ethanol concentrations. The effect of changing temperature on the acidity of HF in these media was also examined. The pKa's were determined using a lanthanum fluoride membrane Fluoride Specific Ion Electrode and a glass pH electrode versus the same reference electrode. The method eliminates the need to determine liquid junction potentials. By determining the pKa for HF in each ethanol/water mixture, at a number of different temperatures, thermodynamic parameters, such as free energy, enthalpy, entropy, and …


The Howard University Reviews Of Science, Vol 1 No 3, Department Of Physics Nov 1972

The Howard University Reviews Of Science, Vol 1 No 3, Department Of Physics

Physics Faculty Publications

No abstract provided.


Water Resources News, Volume 4, No. 8, October 1972 Oct 1972

Water Resources News, Volume 4, No. 8, October 1972

Water Current Newsletter

Updated Version of Proposed Regulations Now Available
EPA Issues New Application Form for Submission of Grant Proposals
Reclamation and Reuse of Solids and Wastes
Fall Meeting of Nebraska Section of AWRA
Technology Transfer Conference
OWRR Director Resigns
Requested Delay in Big Blue Plan
Missouri River Waterfront
Missouri River Basin Commission Notes
Missouri River Money Hurdle
Fish Tale
Water Pollution Veto Overturned
OWRR Priorities for Fiscal 1974


A Preliminary Bibliography And Lake Index Of The Inland Mineral Waters Of The World, D. B. Mccarraher Sep 1972

A Preliminary Bibliography And Lake Index Of The Inland Mineral Waters Of The World, D. B. Mccarraher

Nebraska Game and Parks Commission: Staff Research Publications

This preliminary- bibliography and lake index has been prepared by the author on the basis of information available in the Office of Limnology, Hastings College, Nebraska. Although all source material available there has been searched, it is recognized that many papers, especially those published in regional languages may have been left out. Readers are requested to point out such omissions and any inaccuracies that require correction.

This preliminary bibliography will be circulated among specialists in the subject for corrections to the citations and for suggested additions to the list. It is planned that the paper will then be revised to …


Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part I, Vincent P. Drnevich, S. R. Smith, E. P. Cleveland Aug 1972

Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part I, Vincent P. Drnevich, S. R. Smith, E. P. Cleveland

KWRRI Research Reports

The basic concepts associated with the sledge hammer seismic refraction survey are reviewed and a modified version called down hole shooting is discussed. The latter method has distinct advantages for rock surface profiling. These include: calibration at the end points of the survey, measurement of vertical wave propagation velocities directly, and having a refracted wave ray path for almost the entire survey length.

The down hole shooting seismic refraction survey has been simulated with the digital computer. The method can handle any shaped rock surface profile and generates corresponding travel time curves for the forward and reverse profile surveys. This …


Environmental Status Report - January, February, March/April, May, June 1972, Florida Power Corporation Jul 1972

Environmental Status Report - January, February, March/April, May, June 1972, Florida Power Corporation

Reports

The publication of this issue of the Environmental Status Report incorporates the environmental activities of Florida Power Corporation from January to June, 1972_ As with the last Report, a six-month period is included, rather than two separate quarters, due to a scarcity of time_ It is hoped that the next issue will find the Report back on a Quarterly schedule_ The following is a summarization of the Company's supporting and associated activities from January 1, 1972 to June 30, 1972_ This work has been contributed to by many in the Company, and has been coordinated as a principal responsibility of …


Annual Report And Membership List 1971-72, Iowa Academy Of Science Jul 1972

Annual Report And Membership List 1971-72, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Minutes of the Annual Business Meeting --- 4
Report of the Executive Secretary --- 8
Report of the 84th Session --- 14
Report of the Social Implications Committee --- 16
Report of the Finance Committee --- 18
Treasurer's Report --- 20
Report of the Librarian --- 22
Report of the Recognition and Awards Committee --- 23
Report of the Student Programs Committee --- 26
Report of the Articulation Committee --- 29
Report of the Resolutions Committee --- 31
Report of the Membership Committee --- 32
Constitution, Bylaws, and Articles of Incorporation --- 33
Constitution --- 34
Bylaws --- 38 …


Phyletic Trends In Certain Lineages Of Quaternary Mammals, C. Bertrand Schultz, Lloyd G. Tanner, Lary D. Martin Jun 1972

Phyletic Trends In Certain Lineages Of Quaternary Mammals, C. Bertrand Schultz, Lloyd G. Tanner, Lary D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

Evolutionary trends in certain carnivores, rodents, bovids, and proboscideans are examined. Chronoclines are demonstrated for muskrats, beavers, mammoths, and bison. The Pliocene-Pleistocene boundary and Quaternary climatic fluctuations are also discussed.

The University of Nebraska State Museum contains a large stratigraphically controlled collection of Pleistocene animals. This collection provides a unique opportunity for the study of phyletic trends in certain lineages of mammals. Although a few phylogenetic lineages have been proposed (Schultz and Frankforter, 1946; Hibbard, et al., 1965), this has not been done for the vast majority of Pleistocene mammals. However, there is much more data available than this would …


Spiny Lobster Mariculture In The State Of Florida, W. Richard Boehmer May 1972

Spiny Lobster Mariculture In The State Of Florida, W. Richard Boehmer

Marine Affairs Theses and Major Papers

The purpose of this paper is to introduce the reader to the Florida spiny lobster, Panuluris argus; to show the economic potential for the mariculture of this species by exposing value and size of the U. S. spiny lobster market; to present Florida’s legal provisions for mariculture and how spiny lobster farming would be acceptable; to indicate the biological considerations for the rearing of spiny lobster larva and postlarva; and to introduce a general plan for the mariculture of spiny lobster, that considers the legal provisions of leasing wetlands in Florida and incorporates the biological considerations of spiny lobster.


Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore May 1972

Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore

Theses and Dissertations

Thermodynamic values for cation-cyclic polyether interactions for several systems are reported and discussed in light of ligand geometry, cation selectivity, solvent effects, structure, stoichiometry and the nature of the coordinate bond. Cyclic polyethers are shown to be remarkably good ligands even in water and to have marked selectivity for d0, d10 and d10 s2 cations. Syntheses of one new cyclic polyether and several new mixed cyclic polyether-thioethers are reported. Cyclic chelates with smaller rings are shown to prefer smaller cations, but this selectivity is masked by the hydration energy of the cation. Except for thiophillic cations such as Hg2+ and …


Investigations Of The Algal Productivity Of Selected And Limited Sites Along The Western Shore Of Bear Lake, Utah-Idaho, John William Sigler May 1972

Investigations Of The Algal Productivity Of Selected And Limited Sites Along The Western Shore Of Bear Lake, Utah-Idaho, John William Sigler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations of limited and selected areas along the western shore of Bear Lake were carried out to determine the relative algal productivity with relation to nutrient concentrations and incident sunlight. The primary objective of the study was to determine the effects of nutrient changes in the littoral zone on the western shore on the algal productivity and to establish a baseline of data.

l4C02 radioisotope was used as the principal measurement of organic carbon production as an estimate of productivity. Chlorophyll extracts were made and used as a secondary method for the estimation of productivity. Chemical analysis of …


Model For Predicting Simultaneous Distribution Of Salt And Water In Soils, Satish C. Gupta May 1972

Model For Predicting Simultaneous Distribution Of Salt And Water In Soils, Satish C. Gupta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of water and salt movement in soils is necessary for development of a management scheme for controlling the quality of irrigation return flow. A computer model was developed to predict the distribution of water and salts in the root zone under varying initial and boundary conditions. The model consists of water flow and salt flow sub-models. The water flow sub-model considers the numerical approximation of the general water flow equation with modification for water loss by evapotranspiration (and thus root extraction). The salt flow sub-model considers the mass flow of salts, chemical exchange, precipitation or dissolution of CaCO3 …


Water Resources News, Volume 4, No. 4, April 1972 Apr 1972

Water Resources News, Volume 4, No. 4, April 1972

Water Current Newsletter

New Publications Available from NWRRI
Summer Short Course Planned
NRD's to Become a Reality
Interior Secretary Declares New Legislation Needs
USGS to Step Up Water Resource Investigations
Leagues of Cities Asks for Uniform Pollution Policy
House Passes WPC Bill
Erosion Booklet Released by EPA
Rainfall on Lake Ontario to be Gauged by Radar
Seminar on Coastal Zone
Senate Passes National Environmental Laboratory Law System
American Water Resources Conferences, Call for Papers
Water Pollution Laws Could Shut Marginal Plants
Committee Asks Cutback in Use of Phosphorous
Department Recommends Two Nebraska Projects
Hearing on WRC Principles and Standards
Underground Waste Storage Not …


Abstract Papers Apr 1972

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Starling Control In Sonoma County, Harry F. Mccracken Mar 1972

Starling Control In Sonoma County, Harry F. Mccracken

Vertebrate Pest Conference Proceedings: 5th (1972)

The European Starling, Sturnus vulgaris, began the invasion of California from the north and east as early as the late 1930's. In the winter of 1954, 20,000 of these birds were reported spending the winter in or near the Sonoma, Mendocino Coast. Then in 1961, Walter Ball, at that time the Chief of the Bureau of Rodent and Weed Control in Sacramento, in a talk to the Agricultural Commissioners at the Spring Convention, stated Starlings had been reported from nearly every section of California. In reviewing Walter Ball's paper given at that time, it is somewhat surprising how accurately the …


Carbon And Nitrogen As Regulators Of Algal Growth In Treated Sewage, Edward G. Foree, Charles Reece Scroggin Mar 1972

Carbon And Nitrogen As Regulators Of Algal Growth In Treated Sewage, Edward G. Foree, Charles Reece Scroggin

KWRRI Research Reports

Continuous flow algal cultures were grown under three different growth conditions using secondary sewage treatment plant effluent as the growth medium. The only variable within each run was the hydraulic residence time. The concentrations of growth regulating nutrients were varied between the runs so comparisons of the algal mass, composition, nutrient uptake, and genera could be made. The importance of CO2 availability for algal growth was also studied. A kinetic theory which based algal growth on cellular nutrient concentration was verified. The second phase of the study was a batch culture study in which the same growth medium was …


Catechol Effected Dissolution Of Silicate Minerals, James Maurice Kelley Jan 1972

Catechol Effected Dissolution Of Silicate Minerals, James Maurice Kelley

Dissertations and Theses

The chemical properties of guanidinium tris(catecholato)siliconate, [(H₂N)₂C=NH₂]₂[Si(C₆H₄O₂)₃]·XH₂O (0 < X < 1), precipitated from an ammoniacal solution of silica and catechol by adding guanidinium hydrochloride, (H₂N)₂C=NH·HC1, were studied, and infrared, nmr, x-ray powder diffraction, and analytical data were gathered.

This same compound was, upon addition of' (H₂N)₂C=NH·HC1, isolated from 0.25, M aqueous catechol solutions buffered at pH 10 and containing the silicate minerals albite, andradite, muscovite, pyrophyllite, talc, and wollastonite, and also from unbuffered catechol solutions containing wollastonite and andradite.

It is concluded from this work that the formation of an anionic catechol-silicon complex, Si(C₆H₄O₂)₃²⁻, is largely responsible for the dissolution of the minerals mentioned above. From this conclusion, it is proposed that naturally occurring members of the class of organic compounds to which catechol belongs, the aromatic v̲i̲̲c̲-diols, may play …


Localized Wastewater Treatment Facilities, Robert Russell Garrett Jan 1972

Localized Wastewater Treatment Facilities, Robert Russell Garrett

Retrospective Theses and Dissertations

The report describes an alternative to the use of septic tanks for invidual dwellings. The major problems confronting the larger wastewater treatment plants (0.012 to 10 million gallons per day) in central Florida are also discussed. Solutions in this report are for individual and multi-unit dwelling treatment systems (to 0.06 MGD). these units can provide 90% biochemical oxygen demand (BOD) and suspended solids (SS) removal in accord with new state and county regulations. A comparison of the large versus the small plants reveals that small innovative plants, though more expensive, are more environmentally sound than the poorly operated large facilities. …


Studies To Develop And Investigate An Inverse Formulation For Numerically Solving Three-Dimensional Free Surface Potential Fluid Flows, Roland W. Jeppson Jan 1972

Studies To Develop And Investigate An Inverse Formulation For Numerically Solving Three-Dimensional Free Surface Potential Fluid Flows, Roland W. Jeppson

Reports

An inverse formulation is developed for solving three-dimensional potential fluid flows which considers the magnitudes of the cartesian coordinates x, y, and z as the dependent variables in the space defined by the potential function and two mutually orthogonal stream surface functions whose intersection defines the physical space streamlines. This formulation reverses the usual role of the variables. In this inverse space irregular boundaries, with unknown position in the physical space, such as free surfaces become plane boundaries, and the space of most potential flow problems is a parallelepiped. The basin partial differential equations resulting from this formulation are nonlinear …


A Water Quality Survey, Dale E. Mcmichael Jan 1972

A Water Quality Survey, Dale E. Mcmichael

Journal of the Minnesota Academy of Science

Representative factors influencing water quality in the Albert Lea, Minnesota area were chosen as to assess water quality and changes in the watershed which has been described as an earlier valley of the Shell Rock River.

Parameters representative of chemical, bacterial, and thermal pollution were, respectively, total phosphorous, total and fecal coliform counts, and temperature. Statistical analysis has revealed that significant differences in some parameters measured do exist when various sampling stations of a given sampling date are compared. Statistical analysis also has indicated that correlations do exist between fluctuation patterns when all sampling stations of a given sampling date …


Reaction Of Aqueous Catechol Solutions With Minerals, Boonthong Poocharoen Jan 1972

Reaction Of Aqueous Catechol Solutions With Minerals, Boonthong Poocharoen

Dissertations and Theses

The effectiveness of catechol, an aromatic vic-diol, in dissolving silicate minerals was studied. A synthetic amorphous magnesium trisilicate, Mg₂Si₃O₈∙5H₂O, as well as the minerals olivine, sepiolite, diopside, augite, and enstatite were used to react with catechol in slightly acidic, basic, and neutral solutions. It was found, depending on the solvent used, that 33-52, 8-17, 14-30, 5-11, 3-6, and 0.5-1 % of the minerals dissolved, respectively.

The reaction with Mg₂Si₃0₈·5H₂0 resulted in the formation of crystals of magnesium tris (catecholato) siliconate nonahydrate Mg[Si(Cat)₃]∙9H₂0. Dehydration of the crystals at room temperature resulted in the loss of 6 moles of water to form …


Interactions Of Pesticides And Phytoplankton, Pamela H. Philyaw Jan 1972

Interactions Of Pesticides And Phytoplankton, Pamela H. Philyaw

Retrospective Theses and Dissertations

No abstract provided.


Wjxt Weather Guide, 1822-1972 : A Weather Handbook, George Winterling Jan 1972

Wjxt Weather Guide, 1822-1972 : A Weather Handbook, George Winterling

Jacksonville and Duval Co. Miscellaneous

A history and weather guide of Jacksonville


Detection Of Energetic Heavy Ions, Robert Katz, S. C. Sharma, Mehdi Homayoonfar Jan 1972

Detection Of Energetic Heavy Ions, Robert Katz, S. C. Sharma, Mehdi Homayoonfar

Robert Katz Publications

The delta-ray theory of track structure, applied earlier to such 1-or-more hit detection systems as the inactivation of dry enzymes and viruses, the NaI(Tl) scintillation counter, and nuclear emulsion, is extended to the silver activated phosphate glass dosimeter, the LiF thermoluminescent dosimeter, the creation of free radicals in solid biological substances, solid and liquid organic scintillators, and the ferrous sulfate (Fricke) dosimeter. The response of these systems to both gamma-rays and heavy ions is characterized by two parameters: 1) Dγ37, the dose of gamma-rays at which 37% of the sensitive elements remain unaffected by the radiation, and …


Range And Optimum Growth Concentrations Of Phosphate And Nitrate For Chlamydomonas Reinhardtii, Thomas E. Hill Jan 1972

Range And Optimum Growth Concentrations Of Phosphate And Nitrate For Chlamydomonas Reinhardtii, Thomas E. Hill

Masters Theses

A study was conducted on the alga Chlamydomonas reinhardtii to determine the range and optimum growth concentrations of phosphate and nitrate. There are only a few species of algae for which this type of data is known. Inorganic nutritional data is basic to the understanding of the complexities of phytoplankton ecology and eutrophication.

The "plus" strain of this heterothallic alga was cultured in a TRIS-buffered inorganic medium with various concentrations of sodium phosphate and potassium nitrate and adjusted to a pH of 7.4. The axenic cultures were evaluated at the end of 6 days with a spectrophotometer, at a wavelength …