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Articles 291841 - 291870 of 302421
Full-Text Articles in Physical Sciences and Mathematics
A Study To Improve Dissolved Oxygen Analysis Techniques To Facilitate Water Quality Field Survey Applications, R. W. Raible, M. K. Testerman
A Study To Improve Dissolved Oxygen Analysis Techniques To Facilitate Water Quality Field Survey Applications, R. W. Raible, M. K. Testerman
Technical Reports
This report describes studies made of the temperature characteristics of dissolved oxygen electrodes having a large surface area. Large area electrodes proved to have much longer lifetime between rejuvenations. Many measurements of dissolved oxygen in water need to be made in field situations where recalibration techniques would be difficult and where making temperature corrections is time consuming for operators who may be making numerous measurements. This study was directed toward design of a compensation circuit for a dissolved oxygen electrode which will give the best possible measurement over a large water temperature range of 5° - 35°C without the necessity …
Animal Damage Control In South Dakota, V. Van Ballenberghe
Animal Damage Control In South Dakota, V. Van Ballenberghe
Great Plains Wildlife Damage Control Workshop Proceedings
South Dakota, like virtually all other states, is subject to economic losses from wildlife depredations. We have been in the government sponsored, animal damage control business perhaps longer than some states - our history dates back to the time of Three-toes and the Custer Wolf. In 1973 we are still in that business, perhaps more intensively than ever before, and we regard animal damage control as one of the most pervasive and difficult to solve wildlife problems facing us.
The Missouri River bisects South Dakota into approximately equal "East River" and "West River" land areas. These differ ecologically, and to …
Extension Wildlife Damage Control In Iowa, Tom Berkley
Extension Wildlife Damage Control In Iowa, Tom Berkley
Great Plains Wildlife Damage Control Workshop Proceedings
Introduction
History
Procedures
Results
Conclusion
Exposure To Media Alternatives, Jack Burke
Exposure To Media Alternatives, Jack Burke
Great Plains Wildlife Damage Control Workshop Proceedings
Media use should not be a half way activity done after everything else on your mind is taken care of. The key word is commitment--if you are not ready to give proper preparation which includes understand what each (newspaper, radio, TV, etc.) does best, then don't do anything. There is at least a certain minimum quality standard that must be met--anything less and media exposure can hurt you and your program rather than help you. Seek help. Then select the media to fit your time, money and inclination. Example: Even if you don't buy time--television properly done may cost much …
Proceedings Of The Great Plains Wildlife Damage Control Workshop- December 1973: Contents
Proceedings Of The Great Plains Wildlife Damage Control Workshop- December 1973: Contents
Great Plains Wildlife Damage Control Workshop Proceedings
Cover Pages
Program Planning Committee
Registered Attendance
Preface
Table of Contents
A Brief History Of Extension Predator Control In Missouri, Dan F. Dickneite
A Brief History Of Extension Predator Control In Missouri, Dan F. Dickneite
Great Plains Wildlife Damage Control Workshop Proceedings
Missouri, like many of its neighbors, has long had to content with complaints of damage caused by predatory wildlife. Unlike some other states, however, in Missouri the control, management, restoration, etc. of all bird, fish and game and other wildlife resources of the state is vested in a Conservation Commission to an exclusive degree. Because of this Constitutional mandate, the Conservation Department in Missouri has been the agency primarily responsible for assisting farmers and ranchers with their various wild animal damage control problems. Poisons and explosive or chemical devices are not legal. This legal prohibition not withstanding, Missouri's relatively dense …
D.C. Background On Predator Control Legislation, Michael Frome
D.C. Background On Predator Control Legislation, Michael Frome
Great Plains Wildlife Damage Control Workshop Proceedings
The tragic fiasco of federal predator control as we have known it is finished. The American people will no longer tolerate it. In this age of environmental concern, the people will not allow their tax dollars to be diverted for such a destructive and wasteful war against living wild creatures for the exclusive benefit of the sheep industry. There is now no turning back to old ways.
Indiscriminate trapping, shooting and poisoning have reduced some of the rarest, most beautiful and superbly adapted species of our wildlife heritage to the brink of extinction, although they consitutue a resource that could …
Kansas Predator Damage Control Program, F. Robert Henderson
Kansas Predator Damage Control Program, F. Robert Henderson
Great Plains Wildlife Damage Control Workshop Proceedings
The Extension Division is the off-campus arm of Kansas State University~ a land grant university functioning through 105 county Extension offices involving over 265 county Extension workers that are backed up by some 175 state and area subject matter specialists. Kansas is an agricultural state. The production of livestock in Kansas is an important industry to our state and nation.
Our predator damage control program is an educational effort directed at the goal of reducing livestock losses where possible on individual farms and ranches, in Kansas. Our program has been in existence since 1954. A very important aspect of our …
Preliminary Interpretations Of Coyote Population Mechanics With Some Management Implications, Frederick F. Knowlton
Preliminary Interpretations Of Coyote Population Mechanics With Some Management Implications, Frederick F. Knowlton
Great Plains Wildlife Damage Control Workshop Proceedings
The need for control of coyote (Canis latrans) depredations and a simultaneous demand for recognition of the aesthetic and ecologic values of the species create a conflict in resource utilization that should be resolved through more intensive management. A coyote population model is proposed from current estimates of density, reproduction, population structure, and mobility. Densities of 0.5 to 1.0 coyote per square mile are frequently suggested, with occasional estimates of 4.0 or more per square mile. Reproductive rates fluctuate as functions of the proportion of females that ovulate, the average number of ova shed, and in utero viabilities. …
The Sport Hunting Of Coyotes, Edward L. Kozicky
The Sport Hunting Of Coyotes, Edward L. Kozicky
Great Plains Wildlife Damage Control Workshop Proceedings
In an effort to gain some insight into the sport hunting of coyotes in Kansas, Bob Henderson circulated 586 detailed questionnaires and received 228 replies--an excellent voluntary response.
Time does not permit detailed comments on each question and reply. We shall only hit the highlights, and add some editorial comment where it seems appropriate.
It should be remembered that those who took the time to answer the 35 questions were devotees of the sport. This point is emphasized by the fact that of the 225 hunters who responded, 95 have been hunting coyotes for 20 years or more. The next …
Coyote Denning As A Method Of Damage Control, Walden C. Lemm
Coyote Denning As A Method Of Damage Control, Walden C. Lemm
Great Plains Wildlife Damage Control Workshop Proceedings
The coyote denning operation is a useful method in coyote control, both to control populations and to eliminate problem animals, but a thorough knowledge of coyote behavior prior to and during the denning season is essential for productive results.
Coyotes do not dig their own dens, but enlarge existing holes dug by other animals, often those dug by badgers. Coyote den holes are not difficult to distinguish from holes dug by smaller animals. Being long-legged animals, their den entrances are elongated vertically instead of being round like those of badgers and other short-legged animals.
Coyote Trapping As A Method Of Damage Control, Robert A. Smith
Coyote Trapping As A Method Of Damage Control, Robert A. Smith
Great Plains Wildlife Damage Control Workshop Proceedings
Purpose of Program
Method
Cost of Service
Conclusion
An Assessment Of The Coyote Problem In The Great Plains States, Dale A. Wade
An Assessment Of The Coyote Problem In The Great Plains States, Dale A. Wade
Great Plains Wildlife Damage Control Workshop Proceedings
It has now been 21 months since President Nixon's Executive Order #11643 was issued and there has been a complete annual reproductive cycle in the coyote population of the western states without any major influence by chemical controls. The use of mechanical controls, including non-lethal methods, and greater emphasis on removing only specific offending animals has been advocated during this time as a solution where coyotes prey on domestic animals. With this brief look back, what have been the results?
We do not have absolute data on coyote numbers and livestock depredations resulting from this change in coyote management programs. …
Extension Wildlife Damage Control In Colorado, Dale A. Wade
Extension Wildlife Damage Control In Colorado, Dale A. Wade
Great Plains Wildlife Damage Control Workshop Proceedings
Wildlife damage control in Colorado may be more varied and difficult than in some other states. Colorado has a widely diversified agricultural, industrial and recreational business base and a great range of human density from the Denver Metropolitan area containing approximately half of the state population to the semi-desert and mountain areas where the population density is extremely low.
Approximately 40 percent of the land is federally owned, much of this in large tracts in the western two-thirds of the state. Privately owned land in this western area is primarily distributed along the more accessible valleys of major drainages. It …
Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head
Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head
Masters Theses
"A reconnaissance survey of stream sediments using the minus 80 mesh sieve fraction was made at 53 sites throughout the James River basin, Missouri. Sample sites within the 1460 square miles of the basin were chosen at tributary confluences, suspected contamination sources, and known areas of mineralization. Replicates and stream profiles were taken to check for analytical variation and reproducibility of results. Sediment samples were prepared by a hot nitric acid leach method. The sediments were analyzed using an atomic absorption unit to determine Cu, Pb, Zn, and Cd trace metal contents.
Values of selected streams within the basin were …
Time-Dependent Radiative Cooling Of A Hot Low-Density Cosmic Gas, Menas Kafatos
Time-Dependent Radiative Cooling Of A Hot Low-Density Cosmic Gas, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
Detailed calculations are presented for the radiative cooling of a hot (10^4 K ≤ T ≤ 10^6 K) interstellar gas. Below 10^6 K such a gas is not in ionization equilibrium because it is cooling faster than it is recombining. The gas is more ionized at a particular temperature and emits harder radiation than a gas in equilibrium at the same temperature. Optical forbidden lines, particularly the [0 II], [0 III] lines, are much stronger than the hydrogen Balmer lines. Hydrogen lines, if observable, would show a Balmer decrement not very different from that of a radiatively excited nebula. Results …
General Theory Of Diffusion-Controlled Reactions, Gerald Wilemski, Marshall Fixman
General Theory Of Diffusion-Controlled Reactions, Gerald Wilemski, Marshall Fixman
Physics Faculty Research & Creative Works
A formal mathematical description of diffusion-controlled bimolecular reactions is presented. The theory is completely general with respect to the kinds of reaction processes that may be considered. Besides the presentation of the general formalism, the paper also contains several examples illustrating the application of the theory to a simple many-particule system for simple catalytic bimolecular reactions, including fluorescence quenching. The manner in which approximate solutions may be obtained is also outlined.
Production Of Metastable Ions In Cesium-Atom-Electron Collisions, Kaare J. Nygaard, Yu Bong Hahn
Production Of Metastable Ions In Cesium-Atom-Electron Collisions, Kaare J. Nygaard, Yu Bong Hahn
Physics Faculty Research & Creative Works
The structure in the total electron-impact ionization cross section in cesium can be partially accounted for by the mechanisms of autoionization and excitation ionization of 5p electrons. For electron energies above 17 eV a large fraction of the ions are metastable and can de detected by Auger emission from a metal surface. The experiment was performed in a cesium-atom-electron crossed-beam apparatus, and the metastable ions were counted with a channel electron multiplier. The metastable-ion count rate was a factor of 100 higher than that due to photons from atomic and ionic transitions. We have measured the over-all excitation function for …
Molecular Beam Measurements Of Total Collision Cross Sections Of H 22o, William R. Snow, J. T. Dowell, J. G. Chevrenak, H. E. Berek
Molecular Beam Measurements Of Total Collision Cross Sections Of H 22o, William R. Snow, J. T. Dowell, J. G. Chevrenak, H. E. Berek
Physics Faculty Research & Creative Works
The total cross section for H22O-H22O scattering is measured with a supersonic nozzle beam system. The primary beam has a narrow velocity distribution, and the velocity is varied by control of the nozzle temperature. Velocities are determined by time-of-flight techniques. Cross sections obtained are averages over a Maxwellian distribution of the target molecules. Data at three velocities are presented. The cross sections for H2O are surprisingly small, for example, 3.07 x10-14 cm2 at 1x105 cm/sec, indicating little contribution from the dipole-dipole interaction.
Chemical Shift Parameters For Shallow Donors In Semiconductors, Edward Boyd Hale
Chemical Shift Parameters For Shallow Donors In Semiconductors, Edward Boyd Hale
Physics Faculty Research & Creative Works
A model for a shallow donor impurity in a semiconductor is used to calculate two relationships and several conditions involving the chemical shift parameters. The model is based on the standard effective mass form for the donor electron wave function, the existence of a potential in the chemical cell which may be real, pseudo, or rather general in nature, and a few somewhat restrictive approximations. The parameters, Δ, δ and Λ are theoretically calculated and are shown to be related if the approximations are valid. These parameters determine the 1S multiplet level structure and it is shown how properties of …
Projected Hartree Product Wavefunctions. Viii. Relationship Of Dods And Scf Orbitals For Be, Gordon A. Gallup
Projected Hartree Product Wavefunctions. Viii. Relationship Of Dods And Scf Orbitals For Be, Gordon A. Gallup
Gordon Gallup Publications
Projected Hartree product wavefunctions. VIII. Relationship of DODS and SCF orbitals for Be
Regional Hydrothermal Alteration Of The Leadville Limestone (Mississippian) Of Central Colorado, L. V. Benson
Regional Hydrothermal Alteration Of The Leadville Limestone (Mississippian) Of Central Colorado, L. V. Benson
United States Geological Survey: Staff Publications
Massive metallic-sulfide deposits were implaced in the Leadville Limestone {Mississippian) of Central Colorado less than 70 million years ago. The thermal fluids which precipitated ore at Gilman, Colorado have regionally altered the Leadville Limestone. The sequence of alteration began with the recrystallization of limestone to a dark medium~grained dolomite containing a homogeneous distribution of Fe. This Was followed by partial recrystallization of the medium-grained dolomite to coarse-clear dolomite which contains an inhomogeneous distribution of Fe. The resulting banded rock is known as "zebra rock" . Precipitation of Si0 2 (jasperoid) occurred next. The jaspe=oid formed prior to the deposition of …
Seismicity Preceding Moderate Earthquakes In California, Robert L. Wesson, William L. Ellsworth
Seismicity Preceding Moderate Earthquakes In California, Robert L. Wesson, William L. Ellsworth
United States Geological Survey: Staff Publications
Regional seismicity data have been examined to determine the nature of seismicity in the years preceding these moderate earthquakes in California: 1952 Kern County (M = 7.7), 1963 Watsonville (M = 5.4), 1964 and 1967 Corralitos (M = 5.0, 5.3), 1966 Parkfield-Cholame (M = 5.1, 5.5), 1968 Borrego Mountain (M = 6.4), 1969 Santa Rosa (M = 5.6, 5.7), and 1971 San Fernando (M = 6.4). In each instance the moderate earthquakes occurred in areas characterized by a relatively high level of small earthquake activity. In most cases the preceding activity in the area immediately surrounding the epicenter was high …
Grey Kangaroo Management Programme, Department Of Agriculture, Western Australia
Grey Kangaroo Management Programme, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
The Grey Kangaroo Management Programme, introduced in 1971 by the Department of Fisheries and Fauna, is designed to ensure the long-term conservation of the grey kangaroo, while at the same time recognising the right of the landholder to protect his primary production from damage.
One of the points which has arisen after examination of the programme is that some individual farmers are not fully aware of the requirements of the regulations.
Production And Decay Of Double L Vacancies In Argon And Phosphorus, M. Eugene Rudd, B. Fastrup, P. Dahl, F. D. Schowengerdt
Production And Decay Of Double L Vacancies In Argon And Phosphorus, M. Eugene Rudd, B. Fastrup, P. Dahl, F. D. Schowengerdt
M. Eugene Rudd Publications
Measurements have been made at two laboratories which indicate that the structure reported at 450-550eV in the electron spectrum from Ar+-Ar collisions by Ogurtsov, Flaks, and Avakyan is spurious. It is argued that the double L vacancies which they invoke to explain the structure are more likely to decay by the two-step Auger process L 2→LM2→M4 than by the one-step process L2→M3 suggested by these authors. Evidence supporting this is found in our electron spectra from P+-Ar collisions, where it is known from energy-loss and charge-state measurements that double …
Autoionization Of He And Autodetachment Of He- Following Bombardment By H+, H2+, He+, And He Atoms, F. D. Schowengerdt, S. R. Smart, M. Eugene Rudd
Autoionization Of He And Autodetachment Of He- Following Bombardment By H+, H2+, He+, And He Atoms, F. D. Schowengerdt, S. R. Smart, M. Eugene Rudd
M. Eugene Rudd Publications
Presented here are experimental results of a study of the systematics of electron emission from discrete states of He and He- as produced by H+, H2+, He+, and He impacts. The results were obtained by energy analysis of the electrons emitted at angles of 10° to 160°. Projectile energies ranged from 20 to 150 keV. Differential and integrated cross sections are presented for emission of electrons from the 2s2 (1S), 2s2p(3P), the sum of the 2p2 (1D) and 2s2p(1P) autoionizing levels of He, …
The Soil Conservation Service : Its Basis Of Co-Operation With Landowners, G W. Spencer, J. E. Watson
The Soil Conservation Service : Its Basis Of Co-Operation With Landowners, G W. Spencer, J. E. Watson
Journal of the Department of Agriculture, Western Australia, Series 4
The Soil Conservation Act of 1945 set up within the Department of Agriculture a Soil Conservation Service under the control of a Commissioner of Soil Conservation.
The Service aims to promote types of land use which will conserve the soil and prevent or overcome soil erosion. It also aims to educate landholders and the public generally in the aims and practice of soil conservation.
This article relates mainly to farm land activities, and in particular the co-operation of the Service with individual primary producer landholders for the prevention and control of erosion on their land.
Biotope Et Description De Niphargus Altagahizi N. Sp., Amphipode Gammaridé Souterrain Du Liban, N. Alouf
Biotope Et Description De Niphargus Altagahizi N. Sp., Amphipode Gammaridé Souterrain Du Liban, N. Alouf
International Journal of Speleology
Description of a small warm cave situated along the Mediterranean shore; the temperature of water varies from 14 to 19°C. Inhabiting this cave is Niphargus altagahizi, a new species related to orcinus s.l. group. Description of this species and comparison with the other Lebanese species, N. nadarini.
Branchiobdellids (Annelida: Clitellata) From Some Eastern North American Caves, With Descriptions Of New Species Of The Genus Cambarincola, Perry C. Holt
International Journal of Speleology
Branchiobdellids are found as epizoites on crustaceans of the orders Isopoda and Decapoda (cambarine crayfishes) in caves of eastern North America. Species that may be considered as troglobites, since they are not known from epigean waters, appear to be confirmed to truly troglobitic isopods and possibly a few troglobitic crayfishes from Florida and the Tennessee-Kentucky Highland Rim cave belt. The majority of the records of branchiobdellids from caves are of representatives of common epigean forms epizootic un crayfishes. Cross-referenced lists of branchiobdellids, their hosts and cave localities are presented. Some of the new species described are apparently troglobitic or troglophilic, …
Note Sulla Distribuzione Dei Trichoniscidae In Sardegna (Crustacea, Isopoda, Oniscoidea), Roberto Argano, Mauro Rampini
Note Sulla Distribuzione Dei Trichoniscidae In Sardegna (Crustacea, Isopoda, Oniscoidea), Roberto Argano, Mauro Rampini
International Journal of Speleology
The study of the biogeography of the eight species of Isopoda Trichoniscidae from Sardegna brings to consider the faunistic relationships happened in the past between the island and the Pyrenees. Two of the species are eutroglophilous and rather widespread; the other six are troglobic and endemic to Sardinia. Five of the latter show strong affinity to Pyrenees forms. A detailed description is given of the distribution of the various species. This distribution makes possible some observations on the history of the fauna of the island.