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2008

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The Development Of A Replicable Model For Implementation Of A High School Minimum Competency Program, Nils Golden Bayles Jan 2008

The Development Of A Replicable Model For Implementation Of A High School Minimum Competency Program, Nils Golden Bayles

UNLV Retrospective Theses & Dissertations

Problem. A twenty year decline on college entrance examination test scores achieved by high school students and two massive national studies of education in the United States, the Coleman Report and the National Assessment of Educational Progress, highlighted a nationwide concern about student.

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The Development Of A Consensus Management By Objectives Model And A Comparison To The Clark County School District Management And Accountability System For Secondary Schools, Agustin A Orci Jan 2008

The Development Of A Consensus Management By Objectives Model And A Comparison To The Clark County School District Management And Accountability System For Secondary Schools, Agustin A Orci

UNLV Retrospective Theses & Dissertations

The purpose of the study was to examine selected business and education management by objectives (MBO) models and identify the common elements. These elements resulted in a consensus MBO model which was compared to determine agreement with the Clark County School District's Management and Accountability System for Secondary Schools. Educational accountability, the theoretical bases for MBO and MBO models in business and education were treated in the review of the literature. Graphic models developed in the study included the Clark County District's Management and Accountability System for Secondary Schools and a consensus MBO model; A management process based on the …

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Solution Of Heat Transfer And Fluid Flow Problems Using Meshless Radial Basis Function Method, Nagamani Devi Kalla Jan 2008

Solution Of Heat Transfer And Fluid Flow Problems Using Meshless Radial Basis Function Method, Nagamani Devi Kalla

UNLV Retrospective Theses & Dissertations

In the past, the world of numerical solutions for Heat Transfer and Fluid Flow problems has been dominated by Finite Element Method, Finite Difference Method, Finite Volume Method, and more recently the Boundary Element Method. These methods revolve around using a mesh or grid to solve problems. However, problems with irregular boundaries and domains can be difficult to properly discretize; In this thesis, heat transfer and fluid flow problems are solved using Radial Basis Functions. This method is meshless, easy to understand, and even easier to implement. Radial Basis Functions are used to solve lid-driven cavity flow, natural convection in …

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Titanium Hydride Up To 90 Gpa: Synchrotron X-Ray Diffraction Studies, Patricia E Kalita Jan 2008

Titanium Hydride Up To 90 Gpa: Synchrotron X-Ray Diffraction Studies, Patricia E Kalita

UNLV Retrospective Theses & Dissertations

The structure and behavior of titanium hydride was studied on compression to about a megabar. Angle-dispersive as well as energy-dispersive synchrotron X-ray diffraction studies were carried out in situ, in diamond anvil cells, in several compression and decompression sequences. A phase transition from a cubic to a tetragonal structure was observed. The pressure evolution of the diffraction patterns revealed that the cubic (Fm-3m) to tetragonal ((4/mmm) phase transition occurs at about 0.6 GPa. The transition was found to be reversible on decompression from 34 GPa but irreversible on decompression from 90 GPa. The influence of the pressure transmitting medium on …

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Numerical Modeling Of High Temperature Shell And Tube Heat Exchanger And Chemical Decomposer For Hydrogen Production, Gayatri Kuchi Jan 2008

Numerical Modeling Of High Temperature Shell And Tube Heat Exchanger And Chemical Decomposer For Hydrogen Production, Gayatri Kuchi

UNLV Retrospective Theses & Dissertations

This thesis deals with the development of a three-dimensional numerical model of high temperature shell and tube heat exchanger and chemical decomposer to examine the percentage decomposition of a sulfur trioxide gaseous mixture for the production of hydrogen by the sulfur-iodine thermochemical water splitting cycle, a candidate cycle in the U.S. Department of Energy Nuclear Hydrogen Initiative. A counter flow type straight tube shell and heat exchanger concept is chosen for the analysis. The reacting fluid is a mixture of sulfur trioxide gas and water vapor inside the tubes of the heat exchanger and high temperature helium is the gas …

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Neutron Cross-Section Sensitivity Studies In Higher Actinides For Criticality Safety In Reprocessing, Lawrence J Lakeotes Jan 2008

Neutron Cross-Section Sensitivity Studies In Higher Actinides For Criticality Safety In Reprocessing, Lawrence J Lakeotes

UNLV Retrospective Theses & Dissertations

During reprocessing, the spent fuel rod can be divided up into its component parts for separation into different waste streams. These radioactive streams are then directed appropriately toward low-level waste (LLW) storage, high-level waste (HLW) storage, or reuse into a recycled fuel pin. [1]; The issue that requires evaluation is the nuclear reaction of the higher actinides in reprocessing in an aqueous solution with regard to small temperature changes. This will need an analysis of neutron cross section, which is the measure of the probability that a nuclear reaction will occur; The isotopes' cross sections need to be temperature corrected. …

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An Implementation Of Active Objects In Java, George Oprean Jan 2008

An Implementation Of Active Objects In Java, George Oprean

UNLV Retrospective Theses & Dissertations

Active objects are a form of multitasking for computer systems. Active objects manipulate their own execution thread instead of using the execution thread of the object that created them. When a method is invoked on an active object, the call returns immediately and the caller continues execution. Thus, active objects can be utilized to develop parallel applications; Active object model can be implemented in a number of different ways: with patterns, external libraries or extending the language. The solution proposed by this thesis is to implement active objects by extending the Java language with new keywords. We have modified Sun's …

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Attrition Of Esl Foreign-Born Hispanic Students At Csn, Luis B Ortega Jan 2008

Attrition Of Esl Foreign-Born Hispanic Students At Csn, Luis B Ortega

UNLV Retrospective Theses & Dissertations

This qualitative naturalistic study examined the retention barriers for foreign-born Hispanic English as Second Language (ESL) students that dropped out of the College of Southern Nevada (CSN) ESL for-credit program and the need for services they perceived would have helped them succeed. The participants for this study were foreign-born Hispanics who were taking ESL 110B, ESL 111B and ESL 120B (levels 1, 2, and 3) during the 2005-2006 academic year and have since dropped out. The main focus of the study was on institutional and social factors that affected the retention rate of this population at CSN. Four in-depth interviews …

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The Reading Span Test And Its Predictive Power For Reading Comprehension Among Young And Old Adults, Paul James Schroeder Jan 2008

The Reading Span Test And Its Predictive Power For Reading Comprehension Among Young And Old Adults, Paul James Schroeder

UNLV Retrospective Theses & Dissertations

Although many researchers appear to agree on the usefulness of both simple and complex span tasks, many disagree on the specifics of how or why they measure working memory. The following paper considers competing theories of the relationship between working memory tasks and higher order cognitive function. Consideration is given to simple and complex measures of working memory, various theories about them, and theories based on research within the cognitive aging domain. Subsequent discussion reports the findings from a new study aimed at resolving disagreements about the relationship between lower and higher level cognitive abilities in college-age and older adults.

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A Mathematical Model For Computerized Car Crash Detection Using Computer Vision Techniques, Dawn Marie Strianese Jan 2008

A Mathematical Model For Computerized Car Crash Detection Using Computer Vision Techniques, Dawn Marie Strianese

UNLV Retrospective Theses & Dissertations

My proposed approach to the automatic detection of traffic accidents in a signalized intersection is presented here. In this method, a digital camera is strategically placed to view the entire intersection. The images are captured, processed and analyzed for the presence of vehicles and pedestrians in the proposed detection zones. Those images are further processed to detect if an accident has occurred; The mathematical model presented is a Poisson distribution that predicts the number of accidents in an intersection per week, which can be used as approximations for modeling the crash process. We believe that the crash process can be …

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Implementation Of Jpeg Compression And Motion Estimation On Fpga Hardware, Ramakrishna Gopalakrishnan Jan 2008

Implementation Of Jpeg Compression And Motion Estimation On Fpga Hardware, Ramakrishna Gopalakrishnan

UNLV Retrospective Theses & Dissertations

A hardware implementation of JPEG allows for real-time compression in data intensivve applications, such as high speed scanning, medical imaging and satellite image transmission. Implementation options include dedicated DSP or media processors, FPGA boards, and ASICs. Factors that affect the choice of platform selection involve cost, speed, memory, size, power consumption, and case of reconfiguration. The proposed hardware solution is based on a Very high speed integrated circuit Hardware Description Language (VHDL) implememtation of the codec with prefered realization using an FPGA board due to speed, cost and flexibility factors; The VHDL language is commonly used to model hardware impletations …

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Learning In The Context Of Math Anxiety, Michelle Melissa Guillaume Jan 2008

Learning In The Context Of Math Anxiety, Michelle Melissa Guillaume

UNLV Retrospective Theses & Dissertations

Previous studies have examined the effects of math anxiety on working memory and performance. It has been shown that having a high level of math anxiety not only decreases performance, but also interferes with working memory such that the anxiety competes for working memory resources, decreasing the amount of working memory resources available to work on a math task. Previous research has focused on the semantic memory approach, i.e., testing people on what they already know. The current study took this research one step further and looked at learning, specifically stimulus learning, in the context of math anxiety. A well …

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Optimal Foraging Theory And Early Archaic Plant Use At North Creek Shelter, Sara C Hill Jan 2008

Optimal Foraging Theory And Early Archaic Plant Use At North Creek Shelter, Sara C Hill

UNLV Retrospective Theses & Dissertations

Optimal Foraging Theory has received considerable intellectual criticism since its use as an archaeological tool for understanding human behavior. In this thesis, I will evaluate Optimal Foraging Theory with an empirical test from North Creek Shelter, an archaeological site located in the Escalante Basin on the northern portion of the Colorado Plateau. This test will focus on plant utilization by the early Archaic occupants of the site. An environmental reconstruction for the Escalante Basin will be used to determine the range and quantity of plant resources available to the early Archaic occupants of North Creek Shelter. Then a botanical assemblage …

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Xml-Based Implementation Of A Bibliographic Database And Recursive Queries, Kirankumar Jayakumar Jan 2008

Xml-Based Implementation Of A Bibliographic Database And Recursive Queries, Kirankumar Jayakumar

UNLV Retrospective Theses & Dissertations

Structured Query Language (SQL) of relational database model does not have the expressive power to implement recursive queries. Consequently, recursive queries are implemented as an application program in the host language. The newly developed XML schema provides a different setting for database design and query implementation; In this thesis, we design and implement an XML schema and a set of associated queries for a bibliographic database. We will investigate and demonstrate the shortcomings of both Xpath and Xquery as standard query languages for XML-based databases. We then show an efficient implementation of the recursive queries in XSLT programming language.

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Optimization Of Bipolar Plate Design For Flow And Temperature Distributions Using Numerical Techniques, Kiran Mohan Veepuri Jan 2008

Optimization Of Bipolar Plate Design For Flow And Temperature Distributions Using Numerical Techniques, Kiran Mohan Veepuri

UNLV Retrospective Theses & Dissertations

Although water is fed controllably into the flow channels in the bipolar plates surrounding the membrane electrode assembly (MEA), the complex flow geometry can lead to non-uniformity of the flow and temperature distribution inside the channels. In addition, non-uniform temperature distribution in the cell will affect the electrochemical process for hydrogen production or fuel cell applications. There are many studies on the theoretical analysis of fuel cells, but not many have been reported on the characteristics of the PEM electrolyzer; In this thesis work, numerical simulations were carried out on the basic bipolar plate given by the Proton Energy Systems …

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Investigating Shear Capacity Of Rc Beam-Column Joints Using Artificial Intelligence Techniques, Eslam Mohamed Alnaji Hassan Khalifa Jan 2008

Investigating Shear Capacity Of Rc Beam-Column Joints Using Artificial Intelligence Techniques, Eslam Mohamed Alnaji Hassan Khalifa

UNLV Retrospective Theses & Dissertations

Beam-column joints are critical zones in reinforced concrete structures. The behavior of joints is very complex and governed by different mechanisms such as flexure, shear, and bond stress between the reinforcement and the concrete. Shear transfer mechanisms through the joint are one of the most important factors affecting the joint performance. Shear failure occurring in the joint can lead to severe damage and may result in the collapse of the structure. This thesis presents an investigation into the shear capacity of reinforced concrete beam-column joints. The performance is influenced by several key parameters. An analysis is carried out to simulate …

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Implementation Of Bma Based Motion Estimation Hardware Accelerator In Hdl, Nachiket Jugade Jan 2008

Implementation Of Bma Based Motion Estimation Hardware Accelerator In Hdl, Nachiket Jugade

UNLV Retrospective Theses & Dissertations

Motion Estimation in MPEG (Motion Pictures Experts Group) video is a temporal prediction technique. The basic principle of motion estimation is that in most cases, consecutive video frames will be similar except for changes induced by objects moving within the frames. Motion Estimation performs a comprehensive 2-dimensional spatial search for each luminance macroblock (16x16 pixel block). MPEG does not define how this search should be performed. This is a detail that the system designer can choose to implement in one of many possible ways. It is well known that a full, exhaustive search over a wide 2-dimensional area yields the …

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Standardization Of References Using Hidden Markov Model, Swamynathan Sambamurthy Jan 2008

Standardization Of References Using Hidden Markov Model, Swamynathan Sambamurthy

UNLV Retrospective Theses & Dissertations

In general, technical papers are augmented with a list of bibliographic citations to support the arguments and the merits of the approach presented. Each and every citation is made up of parts like author, journal, volume, book etc. Extracting the parts of the citation from a written document and properly separating into its parts is the problem that is being addressed in this thesis; We use an Information Extraction (IE) technique based on Hidden Markov Model (HMM) to solve this problem. This solution consists of the design of an HMM, the training of the HMM with tagged data, and an …

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Pipelined Implementation Of Jpeg Image Compression Using Hdl, Arun Kumar Reddy Toomu Jan 2008

Pipelined Implementation Of Jpeg Image Compression Using Hdl, Arun Kumar Reddy Toomu

UNLV Retrospective Theses & Dissertations

This thesis presents the architecture and design of a JPEG compressor for color images using VHDL. The system consists of major parts like color space converter, down sampler, 2-D DCT module, quantization, zigzag scanning and entropy coDing The color space conversion transforms the RGB colors to YCbCr color coDing The down sampling operation reduces the sampling rate of the color information (Cb and Cr). The 2-D DCT transform the pixel data from the spatial domain to the frequency domain. The quantization operation eliminates the high frequency components and the small amplitude coefficients of the co-sine expansion. Finally, the entropy coding …

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Comparison Of Confidence Intervals For Binomial Proportions, Narain Armbya Jan 2008

Comparison Of Confidence Intervals For Binomial Proportions, Narain Armbya

UNLV Retrospective Theses & Dissertations

The main objective of this thesis is to compare the performance of confidence intervals for binomial proportions and also propose a Bayesian analysis for estimating the credible sets. In this thesis, a combination of analytical and numerical techniques is used to compare the Wald interval, exact interval and obtain the Bayesian credible sets for the binomial distribution when p is close to 0 or 1. Uniform and Beta priors were used and the credible sets were obtained. The statistical package R was used for this purpose.

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Mathematical Model To Simulate A Hybrid Lighting System, Ahmad Abu Heiba Jan 2008

Mathematical Model To Simulate A Hybrid Lighting System, Ahmad Abu Heiba

UNLV Retrospective Theses & Dissertations

Hybrid solar lighting (HSL) technology is a relatively new technology to utilize natural sunlight along with the traditional electric lighting to light the interior spaces. HSL systems concentrate the sunlight onto a bundle of optical fibers. The optical fibers are routed into the interior space and coupled with cylindrical rods to diffuse the light. A lighting sensor modulates the amount of electric energy depending on the amount of natural light available; This study presents a simplified mathematical model to predict the output of the HSL system based on the amount of the available solar radiation. The model is verified via …

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Exploratory Study Of Construction Safety Culture Through Systems Thinking, Charles J. Jr Benford Jan 2008

Exploratory Study Of Construction Safety Culture Through Systems Thinking, Charles J. Jr Benford

UNLV Retrospective Theses & Dissertations

Since its conception, in 1986 after the Chernobyl accident, the term "safety culture" has gained major popularity throughout many systems, especially the construction industry. Although this concept has gained much popularity over the course of two decades, it remains a heavily debated topic between advocates and skeptics for various reasons. Much of the skepticism is due to the failure of proponents of the concept to clearly define and provide an understanding of those factors that comprise what "safety culture" is, and how it can be achieved. A system (particularly a construction system) that possesses a safety culture is one in …

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The Three Saras, Peter Golub Jan 2008

The Three Saras, Peter Golub

UNLV Retrospective Theses & Dissertations

There are two important foundations upon which my poetry stands: (1) Epistemologically I am an empiricist, not a realist; (2) my poetry is not empirical. That is, it operates in the realm of the thought experiment --the laboratory of the mind. This demon is a good analogy to how I write poetry. I usually get the urge to write a poem after thinking about a question, or a fact. In Maxwell's gedankenexperiment the fact is the second law of thermodynamics, and the question is: What if a demon partitioned the fast and slow molecules in a box?;Hence, there is this …

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Self-Stabilizing Protocol For Anonymous Oriented Bi-Directional Rings Under Unfair Distributed Schedulers With A Leader, Chitwan Kumar Gupta Jan 2008

Self-Stabilizing Protocol For Anonymous Oriented Bi-Directional Rings Under Unfair Distributed Schedulers With A Leader, Chitwan Kumar Gupta

UNLV Retrospective Theses & Dissertations

We propose a self-stabilizing protocol for anonymous oriented bi-directional rings of any size under unfair distributed schedulers with a leader. The protocol is a randomized self-stabilizing, meaning that starting from an arbitrary configuration it converges (with probability 1) in finite time to a legitimate configuration (i.e. global system state) without the need for explicit exception handler of backward recovery. A fault may throw the system into an illegitimate configuration, but the system will autonomously resume a legitimate configuration, by regarding the current illegitimate configuration as an initial configuration, if the fault is transient. A self-stabilizing system thus tolerates any kind …

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Simulation Of Optical Properties Of Quantum Dots, Anupam Kumar Jan 2008

Simulation Of Optical Properties Of Quantum Dots, Anupam Kumar

UNLV Retrospective Theses & Dissertations

Nanotechnology devices based on quantum dots have very interesting applications because of the unique characteristics that quantum dots exhibit. In addition to the very small size and operation almost at the speed of light, many important characteristics of quantum dots such as absorption and extinction can be exploited to design devices with a wide range of applications. The study of metallic quantum dots is also a very exciting and interesting field in engineering because of their immense application and relevance to Surface Enhanced Raman Spectroscopy (SERS); In this thesis, the variation in absorption spectra over a changing array of parameters …

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A Study Of Monge Matrices With Applications To Scheduling, Revanth Pamballa Jan 2008

A Study Of Monge Matrices With Applications To Scheduling, Revanth Pamballa

UNLV Retrospective Theses & Dissertations

In this study of Monge properties I summarize a few aspects of the rich material based on these properties. Monge properties are related to the theory of convexity and just as convexity is important in classical Mathematics so is the theory of Monge properties important in Computer Science. In this thesis I will summarize a few aspects of Monge properties. I compare some of the different properties and show how that they all go back to Gaspard Monge's original ideas. I will highlight a number of new results in scheduling and show how Monge properties and Monge-like properties play a …

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Formula For Success: How Las Vegas Became The Entertainment Capital Of The World, Scott M Pruett Jan 2008

Formula For Success: How Las Vegas Became The Entertainment Capital Of The World, Scott M Pruett

UNLV Retrospective Theses & Dissertations

This paper will espouse the theory that Las Vegas was able to evolve into the entertainment capital of the world by establishing itself as an island of controlled social deviance. That is to say that the city became an area of regulatory exception---one with distinct legal differences in a limited geographical area---and allowed a degree of social deviance by permitting behaviors that would be illegal in nearly any other American city. My research will show that when such an environment enables its visitors to experience extended periods of pleasurable sensory stimulation, whether the inducement be physical, psychological, or chemical, this …

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Framework For Simulation Of Fault Tolerant Heterogeneous Multiprocessor System-On-Chip, Bisrat Tafesse Jan 2008

Framework For Simulation Of Fault Tolerant Heterogeneous Multiprocessor System-On-Chip, Bisrat Tafesse

UNLV Retrospective Theses & Dissertations

Due to the ever growing requirement in high performance data computation, current Uniprocessor systems fall short of hand to meet critical real-time performance demands in (i) high throughput (ii) faster processing time (iii) low power consumption (iv) design cost and time-to-market factors and more importantly (v) fault tolerant processing. Shifting the design trend to MPSOCs is a work-around to meet these challenges. However, developing efficient fault tolerant task scheduling and mapping techniques requires optimized algorithms that consider the various scenarios in Multiprocessor environments. Several works have been done in the past few years which proposed simulation based frameworks for scheduling …

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Three-Dimensional Numerical Study Of Proton Exchange Membrane Fuel Cell Design, Jianfei Wu Jan 2008

Three-Dimensional Numerical Study Of Proton Exchange Membrane Fuel Cell Design, Jianfei Wu

UNLV Retrospective Theses & Dissertations

Performance of proton exchange membrane (PEM) fuel cells is dependent of a set of complex physical and chemical processes occurring simultaneously. Bipolar plates are important components of PEM fuel cells because they are the first stage of the flow distribution system. A non-uniform flow distribution across the active reaction area within PEM fuel cells will probably lead to an unbalanced use of the precious catalyst, and a lower overall efficiency of the device than expected. A three-dimensional numerical model has been developed to evaluate the PEM fuel cell including the current collectors, flow channels, gas diffusion layers, and membrane. This …

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Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright Jan 2008

Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright

UNLV Retrospective Theses & Dissertations

Understanding the role of nitrate in the speciation of actinides is important in order to determine the necessary data for extraction modeling of the UREX process. The focus of this project is on the fundamental chemistry of uranium (U) in the tributyl phosphate (TBP) extraction system, with emphasis on the effect of nitrate on actinyl speciation. Speciation calculations can be performed if stability and solubility constants for the chemical species formed under the examined conditions are known. The stability constant of the uranyl-TBP complex was evaluated under a variety of conditions. The variables were nitric acid, uranyl, total nitrate concentration, …

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