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Traps for Saving Gas at Oil Wells

Description: Technical paper issued by the Bureau of Mines over the use of gas traps at oil wells. Different types of traps are presented and discussed. This paper includes photographs, and illustrations.
Date: February 1919
Creator: Hamilton, Walter Raleigh
Partner: UNT Libraries Government Documents Department

[Rat trap]

Description: Photograph of a homemade rat trap. There are a series of sticks holding up a large board with large rocks resting on top.
Date: 195u
Creator: Clark, Joe
Partner: UNT Libraries Special Collections

Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

Description: Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and “trap-shy” species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.
Date: January 1, 2005
Creator: Ulyshen, Michael D., James L. Hanula, and Scott Horn
Partner: UNT Libraries Government Documents Department

Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

Description: Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and à€œtrap-shy” species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.
Date: January 1, 2005
Creator: Ulyshen, Michael D., James L. Hanula, and Scott Horn
Partner: UNT Libraries Government Documents Department

Evaluation of a Common Carp (Cyprinus carpio L.) Exclusion and Trapping Device for Use in Aquatic Plant Founder Colony Establishment

Description: The focus of this study was to design and evaluate a trapping system that would reduce populations of common carp within water bodies in conjunction with establishment of native aquatic macrophytes founder colonies. A pond study and field study were conducted. A pond study was performed at the Lewisville Aquatic Ecosystem Research Facility, located in Lewisville, Texas, followed by a field study within a constructed wetland located in southern Dallas, Texas. For the pond study, twelve funnel traps were constructed (four reps of each type: control, dual-walled and ring cage). Two anti-escape devices were tested with funnels including steel fingers and hinged flaps. Ring cage and dual-walled treatments were planted using native pondweeds, while controls were left unplanted (additional bait and a drift fence scenarios were also tested). Common carp were introduced into the study pond. Chi-square statistical analyses were utilized and showed ring cage treatments using fingers as well as the use of a drift fence to be most effective. Following completion of the pond study, the two most effective treatments (controls and ring cages) were tested within the Dallas, Texas wetland; no carp were caught during the field test.
Date: May 2008
Creator: Williams, Paul Edwin
Partner: UNT Libraries

Development of a high intensity EBIT for basic and applied science/011

Description: The electron-beam ion trap (EBIT) is a device for producing and studying cold, very highly charged ions of any element, up to a fully ionized U{sup 92+}. These highly charged ions occur in hot plasmas and therefore play important roles in nuclear weapons, controlled fusion, and astrophysical phenomena. The remarkable interaction of these ions with surfaces may lead to technological applications. The highly charged ions can either be studied inside the EBIT itself with measurements of their x-ray emission spectra, or the ions can be extracted from the EBIT in order to study their interaction with solid material. Both types of measurements are being pursued vigorously with the two existing low-intensity EBITs at LLNL and with similar EBITs that have been built at six other laboratories around the world since the EBIT was first developed at LLNL 10 years ago. However, all existing EBITs have approximately the same intensity as the original LLNL EBIT; that is, they all produce about the same number of very-highly-charged ions (roughly 2 x 10{sup 6} per second) and the same number of x-ray photons (roughly 10{sup 7} per second). The goal of the High-Intensity-EBIT project is to increase the x-ray emission per centimeter of length along the electron beam by a factor of 100 and to increase the ion output by a factor of 1000. This dramatic increase in intensity will enable the next generation of basic and applied experimental research in the structure of highly charged ions. For example, the precision of EBIT x-ray measurements of atomic energy levels- which is now limited by count rate-can be improved by an order of magnitude, and new applications in surface science, nanotechnology, and microscopy will be possible with the expected intense ion beams. When the high ion output is combined with the demonstrated low emittance ...
Date: February 5, 1998
Creator: Marrs, R. E.
Partner: UNT Libraries Government Documents Department

How to Destroy Rats

Description: Report discussing the most effective methods for destroying and controlling rat populations. Methods discussed include rat-proofing buildings, withholding food, and using predators, traps, poisons, or fumigation.
Date: 1909
Creator: Lantz, David E. (David Ernest)
Partner: UNT Libraries Government Documents Department

DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER).

Description: The realization of a paradigm chaotic system, namely the harmonically driven oscillator, in the quantum domain using cold trapped ions driven by lasers is theoretically investigated. The simplest characteristics of regular and chaotic dynamics are calculated. The possibilities of experimental realization are discussed.
Date: September 3, 2002
Creator: JAMES, DANIEL F
Partner: UNT Libraries Government Documents Department

Final Technical Report: "New Tools for Physics with Low-energy Antimatter"

Description: The objective of this research is to develop new tools to manipulate antimatter plasmas and to tailor them for specific scientific and technical uses. The work has two specific objectives. One is establishing the limits for positron accumulation and confinement in the form of single-component plasmas in Penning-Malmberg traps. This technique underpins a wealth of antimatter applications. A second objective is to develop an understanding of the limits for formation of cold, bright positron beams. The research done in this grant focused on particular facets of these goals. One focus was extracting tailored beams from a high-field Penning-Malmberg trap from the magnetic field to form new kinds of high-quality electrostatic beams. A second goal was to develop the technology for colder trap-based beams using a cryogenically cooled buffer gas. A third objective was to conduct the basic plasma research to develop a new high-capacity multicell trap (MCT) for research with antimatter. Progress is reported here in all three areas. While the goal of this research is to develop new tools for manipulating positrons (i.e., the antiparticles of electrons), much of the work was done with test electron plasmas for increased data rate. Some of the techniques developed in the course of this work are also relevant to the manipulation and use of antiprotons.
Date: October 2, 2013
Creator: Surko, Clifford M.
Partner: UNT Libraries Government Documents Department

Flow patterns in sodium cold trap crystallizers

Description: From joint meeting of the American Nuclear Society and the Atomic Industrial Forum and Nuclear Energy Exhibition; San Francisco, California, USA (11 Nov 1973). A simple. inexpensive flow distribution device is required for sodium cold trap crystallizers. The use of inlet mixing nozzles to promote uniform crystallizer flow distribution was investigated. Usually, the inlet to the crystallizer is a straight pipe entering at one point of the annulus. The work compared the conventional inlet nozzle to a 90 deg elbow pointing horizontally at the top of the annulus. The nozzle length between the bend and the outlet of the nozzle was two pipe diameters. The nozzle diameter was the same as the crystallizer inlet pipe. The flow patterns were evaluated using a water model of the crystallizer tank. The results indicate that modification of the crystallizer inlet pipe to a 90 deg elbow directed tangentially on the annulus centerline will produce signficant improvement of flow distribution and should provide increased crystallizer volume effectiveness. The improvement is more pronounced at low flow rates than at high flow rates. (auth)
Date: October 1, 1973
Creator: Lester, D.H. & Bloom, G.R.
Partner: UNT Libraries Government Documents Department

FLUORINE DISPOSAL USING CHARCOAL

Description: Wood, coke, and coconut-shell charcoals were evaluated for fluorine entrapment. The coconut-shell charcoal produced the smallest amount of solid and liquid reaction products. Efficient removal of fluorine was accomplished by the coconut-shell charcoal in a 5-in.-diameter reactor with a feed containing 25% fluorine at flow rates from 100 to 400 scfh and reactor-wall temperatures of 1200 to 1800 deg F. (C.J.G.)
Date: July 26, 1960
Creator: Houston, N.W.
Partner: UNT Libraries Government Documents Department

CONTROL OF OXYGEN CONCENTRATION IN A LARGE SODIUM SYSTEM

Description: Data on the performances of two types of cold traps in the 50,000-lb radioactive sodium system at the SRE are tabulated. The rates were determined when trap inlet oxygen concentrations were at 8 to 10 parts per million. Oxygen concentration was readily controlled to 8 ppm using a cold trap. Extraction of oxygen from sodium by zirconium at 1200 deg F (hot trapping) reduces the concentration below the limit of detection, i.e., oxide solubility saturation temperature below 225 deg F. The theoretical limit for the equilibrium oxygen concentration was calculated to be less than 7 x 10/sup -6/ ppm. The observed extraction rate of 0.009 lb oxygen/hr was one-half of the rate predicted from material behavior studies. (auth)
Date: December 1, 1959
Creator: Hinze, R B
Partner: UNT Libraries Government Documents Department

THE SOLUBILITY OF NITROGEN AND OXYGEN IN LITHIUM AND METHODS OF LITHIUM PURIFICATION

Description: Experiments were conducted to determine the solubility of N and O in Li at 250 to 450 ction prod- C and to determine which of several possible purification methods is most effective in reducing the N and O content of Li. The solubility of N in Li increased from 0.04 wt.% at 250 ction prod- C to 1.31 wt.% at 450 ction prod- C. The solubility of O was found to be 0.010 wt.% at 250 ction prod- C and increased to 0.066 wt.% at 400 ction prod- C. Vacuum distillation, lowtemperature filtration. cold-trapping, and gettering with active metals were investigated as possible purification methods to reduce the N and O content of Li. Of the techniques studied, gettering with active metals was found to be the most effective method of reducing the N concentration, while cold-trapping and low-temperature filtration were most effective in reducing the O concentration. (auth)
Date: March 17, 1960
Creator: Hoffman, E. E.
Partner: UNT Libraries Government Documents Department

Collective sliding states for colloidal molecular crystals

Description: We study the driving of colloidal molecular crystals over periodic substrates such as those created with optical traps. The n-merization that occurs in the colloidal molecular crystal states produces a remarkably rich variety of distinct dynamical behaviors, including polarization effects within the pinned phase and the formation of both ordered and disordered sliding phases. Using computer simulations, we map the dynamic phase diagrams as a function of substrate strength for dimers and trimers on a triangular substrate, and correlate features on the phase diagram with transport signatures.
Date: January 1, 2008
Creator: Reichhardt, Charles & Reichhardt, Cynthia
Partner: UNT Libraries Government Documents Department

Heavy-light fermion mixtures at unitarity

Description: We investigate fermion pairing in the unitary regime for a mass ratio corresponding to a {sup 6}Li-{sup 40}K mixture using quantum Monte Carlo methods. The ground-state energy and the average light- and heavy-particle excitation spectrum for the unpolarized superfluid state are nearly independent of the mass ratio. In the majority light system, the polarized superfluid is close to the energy of a phase separated mixture of nearly fully polarized normal and unpolarized superfluid. For a majority of heavy particles, we find an energy minimum for a normal state with a ratio of {approx}3:1 heavy to light particles. A slight increase in attraction to k{sub F}a{approx}2.5 yields a ground state energy of nearly zero for this ratio. A cold unpolarized system in a harmonic trap at unitarity should phase separate into three regions, with a shell of unpolarized superfluid in the middle.
Date: January 1, 2009
Creator: Gezerlis, Alexandros; Carlson, Joseph; Gandol, S & Schmidt, E
Partner: UNT Libraries Government Documents Department