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Aerodynamic problems in the design of efficient propellers

Description: From General Analysis: "The purpose of part I of this paper is to show how the loading that gives the minimum induced energy loss can be obtained from rather elementary considerations and to present design charts from which such a plan form can be quickly obtained for any set of design conditions."
Date: August 1942
Creator: Feldman, Lewis
Partner: UNT Libraries Government Documents Department

Metabolic Engineering in Plants to Control Source/sink Relationship and Biomass Distribution

Description: Traditional methods like pruning and breeding have historically been used in crop production to divert photoassimilates to harvested organs, but molecular biotechnology is now poised to significantly increase yield by manipulating resource partitioning. It was hypothesized that metabolic engineering in targeted sink tissues can favor resource partitioning to increase harvest. Raffinose Family Oligosaccharides (RFOs) are naturally occurring oligosaccharides that are widespread in plants and are responsible for carbon transport, storage and protection against cold and drought stress. Transgenic plants (GRS47, GRS63) were engineered to generate and transport more RFOs through the phloem than the wild type plants. The transgenic lines produced more RFOs and the RFOs were also detected in their phloem exudates. But the 14CO2 labeling and subsequent thin layer chromatography analysis showed that the RFOs were most likely sequestered in an inactive pool and accumulate over time. Crossing GRS47 and GRS63 lines with MIPS1 plants (that produces more myo-inositol, a substrate in the RFO biosynthetic pathway) did not significantly increase the RFOs in the crossed lines. For future manipulation of RFO degradation in sink organs, the roles of the endogenous α-galactosidases were analyzed. The alkaline α-galactosidases (AtSIP1 and AtSIP2 in Arabidopsis) are most likely responsible for digesting RFOs in the cytoplasm and may influence the ability to manipulate RFO levels in engineered plants. Atsip1/2 (AtSIP1/AtSIP2 double-knockout plants) were generated and phenotypically characterized based on seed germination patterns, flowering time, and sugar content to observe the impact on RFO sugar levels. The observations and analysis from these lines provide a basis for further insight in the manipulation of resource allocation between source and sink tissues in plants for future research.
Date: August 2013
Creator: Lahiri, Ipsita
Partner: UNT Libraries

Manipulating Sucrose Proton Symporters to Understand Phloem Loading

Description: Phloem vascular tissues transport sugars synthesized by photosynthesis in mature leaves by a process called phloem loading in source tissues and unloading in sink tissues. Phloem loading in source leaves is catalyzed by Suc/H+ symporters (SUTs) which are energized by proton motive force. In Arabidopsis the principal and perhaps exclusive SUT catalyzing phloem loading is AtSUC2. In mutant plants harboring a T-DNA insertion in each of the functional SUT-family members, only Atsuc2 mutants demonstrate overtly debilitated phloem transport. Analysis of a mutant allele (Atsuc2-4) of AtSUC2 with a T-DNA insertion in the second intron showed severely stunted phenotype similar to previously analyzed Atsuc2 null alleles. However unlike previous alleles Atsuc2-4 produced viable seeds. Analysis of phloem specific promoters showed that promoter expression was regulated by Suc concentration. Unlike AtSUC2p, heterologous promoter CoYMVp was not repressed under high Suc conc. Further analysis was conducted using CoYMVp to test the capacity of diverse clades in SUT-gene family for transferring Suc in planta in Atsuc2 - / - mutant background. AtSUC1 and ZmSUT1 from maize complemented Atsuc2 mutant plants to the highest level compared to all other transporters. Over-expression of the above SUTs in phloem showed enhanced Suc loading and transport, but against expectations, plants were stunted. The implications of SUT over-expression to enhance phloem transport and loading are discussed and how it induces a perception of phosphate imbalance is presented.
Date: August 2013
Creator: Dasgupta, Kasturi
Partner: UNT Libraries

Design review report for the MCO loading system

Description: This design report presents the design of the MCO Loading System. The report includes final design drawings, a system description, failure modes and recovery plans, a system operational description, and stress analysis.
Date: June 23, 1997
Creator: Brisbin, S.A.
Partner: UNT Libraries Government Documents Department

Estimation of Seismic Load Demand for a Wind Turbine in the Time Domain: Preprint

Description: Turbines installed in seismically active regions such as the Pacific Rim or the Mediterranean must consider loads induced by base shaking from an earthquake. To account for this earthquake risk, current International Electrotechnical Commission (IEC) certification requirements provide a simplified method for calculating seismic loads which is intended to be conservative. Through the addition of capabilities, it is now possible to simulate earthquake loading of a wind turbine in conjunction other load sources such as wind and control system behavior using the FAST code. This paper presents a comparison of three earthquake loading scenarios of the National Renewable Energy Laboratory (NREL) offshore 5-MW baseline wind turbine: idling; continued operation through an earthquake; and an emergency shutdown initiated by an earthquake. Using a set of 22 earthquake records, simulations are conducted for each load case. A summary of the resulting tower moment demand is presented to assess the influence of operational state on the resulting structural demand.
Date: March 1, 2010
Creator: Prowell, I.; Elgamal, A.; Uang, C. & Jonkman, J.
Partner: UNT Libraries Government Documents Department

New Manufacturing Method for Paper Filler and Fiber Material

Description: The use of fillers in printing and writing papers has become a prerequisite for competing in a global market to reduce the cost of materials. Use of calcium carbonates (ranging from 18% to 30%) as filler is a common practice in the paper industry but the choices of fillers for each type of papers vary widely according to its use. The market for uncoated digital printing paper is one that continues to introduce exciting growth projections and it is important to understand the effect that different types of calcium carbonates have on the paper properties made of 100% eucalyptus pulp. The current study is focused on selecting the most suitable market available calcium carbonate for the production of uncoated Eucalyptus digital printing paper, targeting a potential filler increase of 5% above the currently used filler content. We made hand sheets using 13 different varieties of widely used calcium carbonates [Nine samples of PCC (two rhombic and seven scalenohedral, covering a wide particle size range from 1.2 {micro}m to 2.9 {micro}m), and four samples of GCC (three anionic and one cationic, with a particle size range from 0.7 {micro}m to 1.5 {micro}m)] available in the market followed by a 12” pilot plant paper machine run. The detailed analysis on the main structural, optical and strength properties of the hand sheets found that the most suitable calcium carbonate for uncoated Eucalyptus digital printing paper production is scalenohedral PCC, with a particle size of 1.9 {micro}m for its positive effects on thickness, stiffness, brightness and opacity of paper.
Date: June 26, 2011
Creator: Doelle, Klaus
Partner: UNT Libraries Government Documents Department

Transverse Periodic Beam Loading Effects in a Storage Ring

Description: Uneven beam fill patterns in storage rings, such as gaps in the fill patterns, leads to periodic, or transient loading of the modes of the RF cavities. We show that an analogous effect can occur in the loading of a dipole cavity mode when the beam passes off the electrical center of the cavity mode. Although this effect is small, it results in a variation of the transverse offset of the beam along the bunch train. For ultralow emittance beams, such as optimized third generation light sources and damping rings, this effect results in a larger projected emittance of the beam compared with the single bunch emittance. The effect is particularly strong for the case when a strong dipole mode has been purposely added to the ring, such as a deflecting, or 'crab' cavity. We derive an approximate analytic solution for the variation of the beam-induced deflecting voltage along the bunch train.
Date: May 4, 2009
Creator: Thompson, J.R. & Byrd, J.M.
Partner: UNT Libraries Government Documents Department

Crusader Automated Docking System Phase 3 report

Description: The US Army is developing the next generation of battlefield artillery vehicles, including an advanced, self-propelled howitzer and a companion resupply vehicle. The resupply vehicle is intended to rendezvous with the howitzer near the battlefront and to upload ammunition to the howitzer. The Army has recommended that the vehicles incorporate robotics to increase safety, by allowing the crew to remain inside their vehicles during resupply operations. Oak Ridge National Laboratory has developed an autonomous docking system for a 6-D.F. robotic, ammunition transfer arm. The docking system augments the operator`s abilities by determining the position and orientation (pose) of a docking port. The pose is the location of the x, y, and z reference axes in 3-D space; and the orientation is the rotations--roll, pitch, and yaw--about those axes. Bye precisely determining the pose of the docking port, the robot can be instructed to move to the docking position without operator intervention. The system uses a video camera and frame grabber to digitize images of the special docking port. Custom algorithms were developed to recognize the port in the camera image, to determine the pose from its image features, and to distribute the results to the robot control computer. The system is loosely coupled to the robot and can be easily adapted to different mechanical configurations. The system has successfully demonstrated autonomous docking on a 24-in. tabletop robot and a 12-ft ammunition resupply robot. The update rate, measurement accuracy, continuous operation, and accuracy with obstructed view have been determined experimentally.
Date: March 1, 1996
Creator: Jatko, W.B.; Goddard, J.S.; Ferrell, R.K.; Gleason, S.S.; Hicks, J.S. & Varma, V.K.
Partner: UNT Libraries Government Documents Department

Assembly procedure for Shot Loading Platform

Description: This supporting document describes the assembly procedure for the Shot Loading Platform. The Shot Loading Platform is used by multiple equipment removal projects to load shielding shot in the annular spaces of the equipment storage containers. The platform height is adjustable to accommodate different sizes of storage containers and transport assemblies.
Date: April 1, 1995
Creator: Routh, R.D.
Partner: UNT Libraries Government Documents Department

NMT-7 plan for producing certifiable TRU debris waste for WIPP

Description: Analysis of waste characterization data for debris items generated during a recent six month period indicates that the certifiability of TRUPACT II payload containers packaged at the Los Alamos National Laboratory Plutonium Facility (TA-55) can be increased from approximately 52% of solid waste payload containers to 78% by applying the simple strategies of screening out high decay heat items and sorting remaining items to maintain nuclear material loading at levels below WIPP waste acceptance limits. Implementation of these strategies will have negative impacts on waste minimization and waste management operations that must also be considered.
Date: December 1, 1997
Creator: Montoya, A.J.
Partner: UNT Libraries Government Documents Department

Tritium Loading of Pinellas U-Bed No. 874

Description: The DOE-Richland Office has requested WSRC to supply PNNL with a Pinellas U-bed loaded with tritium for permeation experiments. It is desired to have less than 1000 Ci tritium in the bed to allow shipping without excessive packaging requirements. Pinellas U-Bed No. 874 was loaded with approximately 955 Ci of 98 percent purity tritium on the ETM manifold in the Materials Test Facility in Building 232-H.
Date: September 15, 1999
Creator: Shanahan, K.L.
Partner: UNT Libraries Government Documents Department

Thermal modeling of waste cylinders in a large container

Description: The Fuel Conditioning Facility at the Idaho National Engineering and Environmental Engineering Laboratory, INEEL, is to produce a spent fuel waste product which is essentially a heat-generating ceramic cylinder with a very tight-fitting stainless steel clad. The size of this waste product, which is under development, is such that many of them will fit into one of the large cylindrical containers being considered for use at the Yucca Mountain repository in Nevada. A key concern is how to size the waste cylinders and arrange them inside the container so that the space within the container is efficiently used and ceramic temperatures above about 600 C are not reached. The waste cylinders are all the same size and are uniformly arranged in layers on a triangular pitch. A layer is formed by placing a number of waste cylinders together and orienting them as if they were cans sitting on a shelf. Here the shelf is a flat circular surface whose diameter is that of the inside of the container, 1.481 m (58.3 in). Many parallel shelves, or layers, of cylinders are placed one above the next inside the container. Three packaging concepts were considered for a layer: (1) the cylinders are separated only by open spaces, (2) a metallic, high thermal conductivity matrix is used which has holes (on a triangular pitch) in which the cylinders are centered, and (3) each cylinder is centered in a hexagonal-shaped tube and the tubes are placed side by side to form a large hexagon which fits inside the large container. All three concepts are thermally acceptable. For Concept 1 the temperatures are somewhat insensitive to the choice of fill gas, loose packing is preferable, and 3, 19, and 91 cylinders provide similar good results.
Date: October 1, 1997
Creator: Feldman, E.E.
Partner: UNT Libraries Government Documents Department

Safety evaluation for packaging (onsite) depleted uranium waste boxes

Description: This safety evaluation for packaging (SEP) allows the one-time shipment of ten metal boxes and one wooden box containing depleted uranium material from the Fast Flux Test Facility to the burial grounds in the 200 West Area for disposal. This SEP provides the analyses and operational controls necessary to demonstrate that the shipment will be safe for the onsite worker and the public.
Date: August 27, 1997
Creator: McCormick, W.A.
Partner: UNT Libraries Government Documents Department