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Articles 292651 - 292680 of 302499
Full-Text Articles in Physical Sciences and Mathematics
An Investigation Of Methods For Reuse Of Rubber Tires, Charles Edward Armbruster
An Investigation Of Methods For Reuse Of Rubber Tires, Charles Edward Armbruster
Retrospective Theses and Dissertations
Methods of reusing/recycling the more than 250 million automobile and truck tires which are worn out each year were investigated. The existing methods of reusing tires account for about 30 percent of the volume of scrap tires generated each year. These methods are, Retreading, Reclaiming (by reducing to ground up rubber and fiber), and Tire Splitting (stamp items out of sidewall and tread areas). Several possibilities for reusing/recycling the unused 70 percent were discovered. These methods are as follows: Destructive Distillation -- a method of recovering chemicals from tires by pyrolitic action. It is anticipated that eventually as much as …
Localized Wastewater Treatment Facilities, Robert Russell Garrett
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. …
Electrostatic Precipitation, Robert C. Hinsey
Electrostatic Precipitation, Robert C. Hinsey
Retrospective Theses and Dissertations
No abstract provided.
Analyses Of The Water And Wastewater Systems At Florida Technological University, Fred C. Jensen
Analyses Of The Water And Wastewater Systems At Florida Technological University, Fred C. Jensen
Retrospective Theses and Dissertations
In searching for a subject to meet the M. S. Degree Research Report requirements, I had several objectives in mind. I wanted (1) a project with relevancy in the environmental field which would broaden my understanding of the environmental systems which I have studied, (2) a subject which would allow me to apply some of the Principles which I have learned in Operations Research , and (3) a project which had good practical application. With these objectives in mind, I reviewed the suggested topics presented by the Faculty and selected the FTU Water and Wastewater System Analyses topic which was …
Remote Sensing Of Environmental Parameters, Wendell Princeton Perkins
Remote Sensing Of Environmental Parameters, Wendell Princeton Perkins
Retrospective Theses and Dissertations
Atmospheric pollution in some degree has been around since time began. In recent times it has reached levels in some areas which proved to be harmful to man's health. A brief history review of these occurrences is presented. Laws have been enacted to combat this threat. A brief review of these laws is presented. Instruments for remote sensing of polluting sources are being developed to monitor ambient air quality and aid in enforcing these laws. A review of the techniques employed and the present state of the art is explored. Available instruments are presented in section III-5.
Rapid Mixing In Water And Wastewater Treatment, Randall C. Rector
Rapid Mixing In Water And Wastewater Treatment, Randall C. Rector
Retrospective Theses and Dissertations
No abstract provided.
Steller's Sea Cow In Pleistocene Interglacial Beach Deposits On Amchitka, Aleutian Isknds, L. M. Gard Jr., G. E. Lewis, Frank C. Whitmore Jr.
Steller's Sea Cow In Pleistocene Interglacial Beach Deposits On Amchitka, Aleutian Isknds, L. M. Gard Jr., G. E. Lewis, Frank C. Whitmore Jr.
United States Geological Survey: Staff Publications
The first discovery of Steller's Sea Cow (Hydrodamalis) in place in Pleistocene deposits has been made in interglacial beach sand and gravel 35 m above present sea level on Amchitka, Aleutian Islands. Uranium series dating of the bone indicates that it is about 135,000 yrs old.
Sinkholes In Florida And Their Effect On Man's Environment, Gregory Jackson Skinner
Sinkholes In Florida And Their Effect On Man's Environment, Gregory Jackson Skinner
Retrospective Theses and Dissertations
The primary reason for making the research study on "Sinkholes in Florida and Their Effect on Man's Environment", is an interest in learning more about this somewhat unique phenomenon and how it is likely to affect man in the future, particularly here in Central Florida. This is significant at this time in view of the large number of existing sinkholes, the frequency of occurrence, the projected population and economic growth, and the possible impact this growth may have on future sinkhole occurrences. The research concentrated on possible causes, effects, frequencies, locations and mean of predicting future sinkhole development. There is …
Bahamas Bibliography : A List Of Citations For Scientific, Engineering And Historical Articles Pertaining To The Bahama Islands, Carol Fang, W. Harrison
Bahamas Bibliography : A List Of Citations For Scientific, Engineering And Historical Articles Pertaining To The Bahama Islands, Carol Fang, W. Harrison
Reports
Specialized bibliographies are sometimes needed in connection with the research studies being pursued at the Virginia Institute of Marine Science. The Bahamas Bibliography arose out of the needs of marine geologists, biologists and physical oceanographers engaged in studies of beaches, fishes and inlet currents in the Bahama Islands. Although the present bibliography may suffer from completeness, it significantly surpasses in number of citations the only other known bibliography of like kind.
Wastewater Treatment Plant Control, David Milton Knowles
Wastewater Treatment Plant Control, David Milton Knowles
Retrospective Theses and Dissertations
This report is the result of investigation of the feasibility of increasing the use of autamatic controls at the Florida Technological University Wastewater Treatment Plant. This investigation was to include a literature search and visits to wastewater treatment plants. During the writers course of study, he was privileged to make a series of tests of a residual chlorine analyzer which was made in the school shop. Since this work was closely related to automatic controls the data are included in this report.
Suppression Of Turbofan And Turbojet Engine Generated Noise, Harry David Master
Suppression Of Turbofan And Turbojet Engine Generated Noise, Harry David Master
Retrospective Theses and Dissertations
Every advance in the transformation of heat energy into mechanical energy has involved a noise problem, and in general it increases with the power production. The jet airplane is a good example: the large-scale turbulence of the exhaust gases in the jet forms an unusually intense source of sound the control of which is quite difficult. The additionally generated fan noises add characteristic fan tones which are particularly noticeable on landing approaches. the human ear is the vulnerable receiver of these noises, and the problem becomes one of deciding how much jet engine noise reduction is required for the comfort …
A Study Of Phosphorus Adsorption And Desorption Kinetics On Silicon (111) Surfaces, L. E. Davis, L. L. Levenson, J. J. Melles
A Study Of Phosphorus Adsorption And Desorption Kinetics On Silicon (111) Surfaces, L. E. Davis, L. L. Levenson, J. J. Melles
Physics Faculty Research & Creative Works
Low energy electron diffraction (LEED) and Auger electron spectroscopy (AES) methods were used to characterize the (111) surface of Si wafers before and after the deposition of P2 molecules. Before deposition, the well-known Si(111)-7 LEED pattern was easily obtained by thermal cleaning at 1200 °C. Cleaning was done by electron bombardment in a vacuum chamber with a base pressure of ∼ 10-10 Torr. After cleaning, AES showed that about 10-2 atomic layer of carbon was the only surface contaminant. The sensitivity of our cylindrical AES apparatus for phosphorus was about 10-3 atomic layer. We found that ∼5x10-2 atomic layer of …
Limnology Of Four Bauxite Open-Pit Lakes, George L. Harp, Ronald D. Hubbard
Limnology Of Four Bauxite Open-Pit Lakes, George L. Harp, Ronald D. Hubbard
Journal of the Arkansas Academy of Science
The aquatic flora and fauna and 18 physicochemical characteristics of four bauxite open-pit lakes were studied from September 1969 to August 1970. The least acid lake (pH 3.4-4.4) supported 49 different aquatic insects, plankton, and higher aquatic plants. The most acid lake (pH 2.7-3.2) supported only 26 different plants and animals. Bauxite open-pit lakes within the pH range studied appear to be as relatively unproductive as their coal strip-mine lake counterparts, with which they share physicochemical and biological characteristics. Benthic macrofaunal diversity and abundance appear to be related more closely to distribution and abundance of leaf detritus than to hydrogen-ion …
Fracture Pattern Analysis Employing Remote Sensing Techniques For Groundwater Movement With Environmental Applications: Preliminary Report, Bradford C. Hanson
Fracture Pattern Analysis Employing Remote Sensing Techniques For Groundwater Movement With Environmental Applications: Preliminary Report, Bradford C. Hanson
Journal of the Arkansas Academy of Science
The study will consist of determining the relationship between fracture patterns and porosity-permeability changes in carbonate rocks with emphasis on groundwater movement. These porosity-permeability changes will be measured by relative groundwater movement, in the form of either springs, artesian wells, municipal supplies, or private wells. Relationships will be determined by plotting the positions of the measuring sites and correlating these sites with mapped fractures. Water yield is expected to be markedly greater for sites along fracture traces than for those located at random.
Geoelectrical Possibilities Of Detecting Stream Channels In Carbonate Rocks, Reinhard K. Frohlich
Geoelectrical Possibilities Of Detecting Stream Channels In Carbonate Rocks, Reinhard K. Frohlich
Journal of the Arkansas Academy of Science
Several geoelectrical resistivity methods that may be used to determine the position and flow characteristics of underground water associated with carbonate bedrock and karst development are considered. The most promising method studied employs depth soundings patterned after Schlumberger. The plotting of half electrode separation against apparent resistivity yields a curve which may be used to discriminate between lateral and vertical inhomogeneities in bedrock. A network of depth soundings of this type ultimately may lead to a map that will show geoelectrical anisotropies that may be used to analyze subsurface water courses in carbonate rock.
Stratigraphy And Sedimentary Structures Of A Middle Bloyd Fluvial Sandstone, Washington And Madison Counties, Arkansas, John M. Glenn
Stratigraphy And Sedimentary Structures Of A Middle Bloyd Fluvial Sandstone, Washington And Madison Counties, Arkansas, John M. Glenn
Journal of the Arkansas Academy of Science
A prominent quartz-pebble-bearing sandstone unit crops out at stream level along the East Fork of the White River in Madison County. Detailed geologic mapping indicates that the unit is stratigraphically positioned between the Brentwood and Dye Shale Members of the Bloyd Formation and is not the Greenland Member of the Winslow Fromation as previously supposed. Sedimentary textures and structures of the unit indicate that it was deposited by competent, unidirectional currents flowing in a southerly direction. These currents were related to a broad braided stream system.
Effect Of Increasing Depth On Salinity In The James River Estuary, Maynard M. Nichols
Effect Of Increasing Depth On Salinity In The James River Estuary, Maynard M. Nichols
VIMS Books and Book Chapters
The effects of channel deepening on the salinity and density flow in the James River estuary, Virginia, were studied to predict changes that might affect oyster production. A hydraulic model with 1: 1,000 horizontal and l: 100 vertical scales was employed to integrate three-dimensional changes in salinity and velocity through reaches of variable bottom geometry. After natural characteristics of the tide, current, and salinity were reproduced in the model, tests were run at three levels of steady river inflow, before and after a 3-meter channel deepening. Results were combined with corollary field observations to evaluate changes in present-day ecological conditions. …
Sediments Of The James River Estuary, Virginia, Maynard M. Nichols
Sediments Of The James River Estuary, Virginia, Maynard M. Nichols
VIMS Books and Book Chapters
The James River estuary of the Chesapeake Bay region follows the course of a former river valley drowned within the last 9,000 years by the most recent rise of sea level. The floor is shaped into a central channel bordered by submerged shoals. Observations show suspended sediment is transported mainly by alternating tidal currents and secondarily by the net nontidal estuarine circulation. Transport results in a sequence of grain size distributions reflecting the mixing of two textural end members, clay and sand.
Silty clay is deposited in the river and upper estuary, whereas sand occurs near the mouth. Transitional types, …
Agricultural And Urban Pollution, Morris L. Brehmer
Agricultural And Urban Pollution, Morris L. Brehmer
VIMS Books and Book Chapters
I have modified the scope of this paper slightly to include urban pollution because the pollution problems produced by the agricultural industry are essentially the same as those produced by municipalities. We know that environmental degradation occurs as a result of the discharge and the byproducts from both sources.
In the case of agricultural activities, the terrain has and still is being modified to convert it to crop production. In the livestock industry, large populations of animals are being concentrated into relatively small areas to meet the economic pressures of meat production. With the human population, the numbers of people …
Engineering Works And The Tidal Chesapeake, William J. Hargis Jr.
Engineering Works And The Tidal Chesapeake, William J. Hargis Jr.
VIMS Books and Book Chapters
This paper discusses the tidal tributaries of the ocean and the coastal areas of the mid-Atlantic Bight and the ecological significance of engineering projects. While occasional reference may be made in this paper to remote sensing of problems engendered by engineering works on maritime environments and resources, principal efforts along those Jines are reserved for the group discussion to follow.
The Chesapeake Bay drainage basin_encompasses.almost 65,000 miles and provides space and partial resources for over 11 million people ( 1960) in New York, Pennsylvania, Maryland, Virginia, and the District of Columbia. Two other states, Delaware and West Virginia, to a …
D-Structures And Their Semantics, Rohit J. Parikh
D-Structures And Their Semantics, Rohit J. Parikh
Publications and Research
"Many logicians are familiar with the game theoretic approach to semantics, due to Jaakko Hintikka. This paper by me contains class notes of a logic course at Boston University in fall 1972. It has similar game theoretic ideas, developed quite independently, but influenced by the work of A. Ehrenfeucht. It applies to a larger class of logics, including classical logic, intuitionistic logic and the *-semantics of Ehrenfeucht. The treatment is via D-structures which are finite approximations of infinite structures. For various reasons I did not publish this paper then, but some abstracts, both by myself as well as joint abstracts …
Computer Method For Airport Noise Exposure Forecast, John Michael Bateman
Computer Method For Airport Noise Exposure Forecast, John Michael Bateman
Retrospective Theses and Dissertations
The major problem facing air transportation for the next decade is aircraft noise. The noise level due to the operation of large jet aircraft has created a very serious annoyance problem to the people living near of adjacent to jet airports. The noise problem has developed both for take-off and landing operations of these aircraft with take -off noise causing the greatest annoyance factor. A technique called Noise Exposure Forecast (NEF) has been developed to identify the annoyance factor of these noises to people and activities on the ground. With these NEF ratings or numbers, planners can better determine the …
Conversion And Validation Of Sigart Program, A Progressive Traffic Signal Lights System Computer Model, Dennis F. Troyan
Conversion And Validation Of Sigart Program, A Progressive Traffic Signal Lights System Computer Model, Dennis F. Troyan
Retrospective Theses and Dissertations
The purpose of this research paper was to translate a Computer Model (SIGART), capable of simulating a progressive traffic signal lights system, from Burroughs B5500 FORTRAN II to the IBM 360 FORTRAN IV computer language, to outline the program algorithm, to set up detailed program documentation and to validate this model by applying practical system data. Expansion of the SIGART program by addition of an option to produce a time space plot of the output data utilizing a Calcomp plotter was also to be considered.
Obstacles To Economic Progress In Ethiopia's Red Sea Coast And Gulf Of Aden, Abraham Alemayehu
Obstacles To Economic Progress In Ethiopia's Red Sea Coast And Gulf Of Aden, Abraham Alemayehu
Marine Affairs Theses and Major Papers
Ethiopia is a coastal state whose overall economic progress has been and still is being affected by a number of coastal and related obstacles. This paper will attempt to discuss each and every one of these obstacles and other relevant aspects in order to justify as much as possible Ethiopia's lack of progress in economic development. By no means these are not the only obstacles responsible for affecting the country's entire economic progress. The obstacles that I would like to present here are only those which are more or less directly related to maritime, geographical and geopolitical problems on the …
The U.S. Merchant Fleet: Patterns For The Seventies (U), Glenn Edward Whisler Jr.
The U.S. Merchant Fleet: Patterns For The Seventies (U), Glenn Edward Whisler Jr.
Marine Affairs Theses and Major Papers
An analysis of recent U.S. maritime legislation in order to predict the possible effect it may have on our merchant fleet growth patterns for the seventies. Major attention is devoted to the Merchant Marine Act of 1970 which the Administration and Congress hopes will halt the continuing decline of the U.S. merchant fleet. The investigation is limited to the shipbuilding industry and is concerned primarily with government incentives, provided to both shipbuilders and shipowners, designed to stimulate new building programs. This study finds that the U.S. merchant fleet will experience a healthy growth during this decade as a result of …
The Navy And Aquidneck Island: A Study In The Coastal Zone, Paul Lewis Cohen
The Navy And Aquidneck Island: A Study In The Coastal Zone, Paul Lewis Cohen
Marine Affairs Theses and Major Papers
Navy fleet operating bases are all located within the coastal zone; a unique area neither land nor sea. This paper opens with a brief review of the nature of the coastal zone, followed by a discussion of regulations pending in Congress and an example of one state's coastal zone legislation. Navy policies regarding environmental factors that must be considered in land use management are also discussed. Interactions of the U.S. Naval Base, Newport, and non-Navy interests with the coastal zone of Aquidneck Island are examined to develop a model for analysis of these relationships.
Agriculture And Pollution In Western Australia. Part 1. Background, C V. Malcolm
Agriculture And Pollution In Western Australia. Part 1. Background, C V. Malcolm
Journal of the Department of Agriculture, Western Australia, Series 4
For centuries there has been awareness of pollution but it has received dramatic publicity in recent years.
In Western Australia, provisions for its control are written into the Health Act and many other Acts besides the Environmental Protection Act of 1971.
A number of factors have acted worldwide and locally to increase awareness and concern about pollution, and to justify careful examination of the problems it causes.
Test 1099: International Utility 574 Diesel (Also International 574 Row Crop Diesel), Nebraska Tractor Test Lab
Test 1099: International Utility 574 Diesel (Also International 574 Row Crop Diesel), Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1103: Case 1270 Diesel, Nebraska Tractor Test Lab
Test 1103: Case 1270 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Agriculture And Pollution In Western Australia. Part 2. Pollution Problems In W.A, C V. Malcolm
Agriculture And Pollution In Western Australia. Part 2. Pollution Problems In W.A, C V. Malcolm
Journal of the Department of Agriculture, Western Australia, Series 4
In Part I pollution was defined as a reduction in the usefulness of a resource and its significance in relation to resource fragility was discussed. Pollution problems in Western Australia are here considered in broad geographical regions with further subdivision into pollution types.