Digital Commons Network^™

Modelling Of Gob Inertization With Nitrogen, Michael Michaylov, Elena Vlasseva

U.S. Mine Ventilation Symposium

The paper deals with a modelling of nitrogen distribution throughout gob so that the effect of inertization could be measured. The model takes into account flow transient character, methane liberation and different locations for nitrogen injection. Computer modelling, reflecting mathematical models is done by a specially created computer programme NITRO_ GOB, which allows dealing with different parameters of air leakage, of coal waste distribution as well as of gas picture in the gob before inertization. Effective evaluation of the most important parameters - injection place and nitrogen volume- on gob gas picture is illustrated under typical cross-section profiles of gas …

Mitigation Of Methane Emissions From Coal Mine Ventilation Air, Peter Carothers, Milind D. Deo

U.S. Mine Ventilation Symposium

U.S. EPA's coalbed methane outreach program, (CMOP) has prepared a technical assessment of techniques that combust trace amounts of coal mine methane contained in ventilation air. Control of methane emissions from mine ventilation systems has been an elusive goal because of the magnitude of a typical airflow and the very low methane concentrations. One established and cost-effective use feeds the air into a prime mover in lieu of ambient combustion air. This method usually consumes just a fraction of the flow available from each ventilation shaft. The authors evaluated the technical and economic feasibility of two emerging systems that may …

Niosh/Nci Study Of Exposure To Diesel Exhaust In Underground Mines — An Industry Perspective, Christopher J. Pritchard

U.S. Mine Ventilation Symposium

In 1992, the National Institute For Occupational Safety and Health (NIOSH) initiated a study, funded by the National Cancer Institute (NCI), to evaluate the health effects, if any, involving underground miners exposure to diesel exhaust. An industry organization, the Methane Awareness Research Group (MARG) already in place to respond to gassy mine related issues, was redirected to work with diesel concerns. In 1995, NIOSH released a draft protocol and feasibility assessment, indicating its intent to initiate s study at 14 underground mines, some of which were operated by MARG members. After considerable debate on the study protocol, in-mine industrial hygiene …

Acuta Enews June 1999, Vol.28, No. 6

ACUTA Newsletters

In This Issue

Winners Announced in Student Papers Contest

Conference Offers Many Choices

Dues Notices Mailed

Does It Make Sense?

Board Report

Share Your Expertise

DC at a Glance

Positions Available

Welcome New Members

Introduction: The Challenge Of Risk Communication In A Democratic Society, Richard C. Rich, Robert J. Griffin, Sharon M. Friedman

RISK: Health, Safety & Environment (1990-2002)

The symposium editors review key issues concerning the relationship between risk communication and public participation.

Program Plan For Photovoltaic Buildings In Florida, Florida Solar Energy Center, Gerard Ventre

FSEC Energy Research Center®

This document outlines plans developed by the Florida Solar Energy Center (FSEC) to support photovoltaic (PV) building applications in the State through the next decade. Implementation of the plan will be a collaborative effort among the Florida Energy Office (FEO) of the Department of Community Affairs, Sandia National Laboratories (SNL), the photovoltaic industry, nine end-user groups, and FSEC.

Bistatic Radar Cross Section (Rcs) Characterization Of Complex Objects, Robert L. Eigel Jr.

Theses and Dissertations

This research addresses some phenomenological aspects of bistatic scattering from a complex object with an emphasis on specular, shadowing, dihedral, and cavity effects. Five targets are investigated for their simplicity and ability to highlight certain scattering phenomena. Direct measurements of scattered electromagnetic energy and simulation data is gathered for a frequency bandwidth of 6-18 GHz. Both ray tracing and scattering center approaches are used to describe the bistatic mechanisms. An appraisal of the effectiveness and utility of the monostatic-to-bistatic equivalence theorems (Kell's and Crispin's) and several commercial scattering prediction codes is also accomplished. Simulation data is generated from two different …

Media Coverage Of Epa's Draft Dioxin Reassessment Report, Sharon M. Friedman, Megan A. Fitzpatrick, Brenda P. Egolf

RISK: Health, Safety & Environment (1990-2002)

Using content analysis, the authors examine the utility of news media in democratic decision making.

Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar

Dissertations

The sites at which the development is hindered by real or perceived contamination are called as Brownfield sites. It is a common trend in industry to develop these types of sites with surface and peripheral containments. It might prove unwise to develop the sites in this manner from a long term perspective without considering the associated risk. Because of this, a model has been proposed for long term risk assessments of brownfield containments.

Objectives of this study were to develop a contaminant transport model for flow of contaminants towards the surface and peripheral containments inside the site, a model for …

Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen

Dissertations

Grinding process is introduced to provide fine particles of coal fly ash that enhances the strength gain of cement mortars. It is discovered that grinding can make all the studied fly ashes more suitable for concrete use at higher replacement value than previously anticipated even when the effect of high carbon content is considered.

In this study, new mechanisms for strength gain of fly ash mortars are proposed. They are dispersion and nucleation, which are results from the presence of fly ash in the cement mortar. These effects are shown to enhance the hydration of cement. The pozzolanic action of …

Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim

Dissertations

The study of Water Treatment Plant (WTP) residuals is of recent origin and very little information is available in literature regarding these residuals. These waste materials have high solids contents, even in the mechanically dewatered condition, making it difficult to handle. These, along with stringent environmental regulations have forced the water utilities to look for new disposal options for these residuals. For this purpose as well as for evaluating suitable options for the beneficial reuse of residuals, it is essential to characterize WTP residuals.

As the dewatered residuals are plastic, the researcher may be prompted to treat these materials as …

On Scheduling Input Queued Cell Switches, Shizhao Li

Dissertations

Output-queued switching, though is able to offer high throughput, guaranteed delay and fairness, lacks scalability owing to the speed up problem. Input-queued switching, on the other hand, is scalable, and is thus becoming an attractive alternative. This dissertation presents three approaches toward resolving the major problem encountered in input-queued switching that has prohibited the provision of quality of service guarantees.

First, we proposed a maximum size matching based algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure, and at the same time provides fair service among competing sessions. Like any maximum …

Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski

Dissertations

The objective of this study was the development of a new computer program called PF-Model to analyze pneumatic fracturing of geologic formations. Pneumatic fracturing is an in situ remediation process that involves injecting high pressure gas into soil or rock matrices to enhance permeability, as well as to introduce liquid and solid amendments. PF-Model has two principal components: (1) Site Screening, which heuristically evaluates sites with regard to process applicability; and (2) System Design, which uses the numerical solution of a coupled algorithm to generate preliminary design parameters.

Designed as an expert system, the Site Screening component is a high …

Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li

Dissertations

In high-frequency ranges, the present electronic design automation software has limited capabilities to model electromagnetic (EM) systems where there are strong field effects influencing their characteristics. In this situation, a full-wave simulation tool is desired for the analysis and design of high-speed and non-linear EM systems. It is necessary to explore the interaction between the field and electronic components during a transient process when field effects are more significant. The finite-difference time-domain (FDTD) technique receives growing attention in the area of EM system analysis and simulation due to its simplicity, flexibility and robustness. It is a full-wave simulation method that …

Production Of Submicron Aerosols By Powder Depressurization, Amit Haryani

Theses

Disaggregation of dry powders in shear flow has limitations in producing submicron particles. This study explores a new method for the production of submicron particles by the depressurization of powder aerosols. The depressurization mechanism is based on the rapid depressurization of the aggregated powder through a specially designed nozzle. As the pressure suddenly decreases from very high values inside the aggregates (800 psi) to ambient at the surface of such aggregates, disaggregation takes place due to the force exerted by the gas escaping through their pore structure.

he effect of various process parameters, namely: nozzle diameter, pressure and pretreatment with …

Development Of Icejet Machining Technology, Dimitri V. Shishkin

Theses

This work was concerned with the application of ice powder for material processing. Material cutting and surface cleaning were also studied. As a result, innovative cleaning and etching technology was pioneered. The corresponding technology was designed and demonstrated.

The study involved investigation of water freezing, crushing of generated ice, ice transportation, formation of ice water and ice air streams and, finally, use of this stream for material cutting and cleaning. The theoretical work included investigation of the phase change in water and ice formation, effect of ice temperature on particles behavior and entrainment of ice particles by the water stream. …

Study Of Reactive Media For Chromium Removal From Groundwater By Permeable Barriers, Hemant S. Desai

Theses

The purpose of the study was to select reduction media for application in permeable barriers for removing chromate ions from groundwater emanating from chromium refining sites in New Jersey. The high pH condition of groundwater in such sites is expected to pose limitations on the use of metallic iron (Fe⁰) as the sole reductive medium.

Reasonable reduction kinetics was achieved using iron at pH < 9.2. Several pH lowering media were investigated and were found to have either very slow or very fast dissolution kinetics, which rendered them impractical for use in passive permeable barriers. Two other media, namely: pyrite and siderite minerals have shown promising results, but fell short of achieving the required performance. Detailed investigation of interfacial processes in a batch reactor have shown that the addition of a small amount of a neutral salt can significantly improve chromate reduction kinetics, even at high pH conditions around 10.9.

The formation of passivating layers, which can slowdown the reaction significantly, was found to be important at high pH conditions. It is recommended that an injection system be used with the reactive barrier to …

Radiative Properties Of Ir Materials, Manish R. Babladi

Theses

The objective of this thesis is to study the radiative properties of materials of interest in the infrared range of wavelengths. In particular, three distinct materials have been considered here - Erbium oxide, alumina and quartz. Erbium oxide has unique selective line emission, which gives a high emittance at a particular wavelength and low emittance in the rest of the infrared spectrum. It has applications in the design and development of thermophotovoltaic (TPV) generators. Because of its selective emission properties, erbium oxide assists in concentrating the radiant energy into a narrow band near the bandgap energy of the TPV cell, …

In Situ Enhancement Of Well Recovery By Pneumatic Media Injection, Michael Thomas Galbraith

Theses

The objective of this thesis was to develop a new process for enhancing recovery wells at hazardous waste sites. The process, known as an extended radius well (ERW), involves injection of ceramic beads directly into groundwater plumes to create drainage paths for liquid contaminants. This is a variant of Pneumatic Fracturing, which is a patented in situ remediation process developed to increase permeability of soil and rock formations by injection of high pressure gas.

The research study comprised laboratory investigations, engineering scale tests, and a field pilot demonstration. The laboratory investigations examined the properties of several candidate media to determine …

Development Of A Context-Specific Search Engine, An Executive Information System, And A Novel Www Ready External Cost Model, Amit V. Revankar

Theses

NJPIES is associated with Information Ecology and Sustainability, a holistic approach to environmental data collection, compilation, integration and provision that puts people, not technology, at the center of the environmental information world.

The first main goal of this project was to develop an algorithm and associated computer-based tool that could perform a lifecycle cost analysis for a model system. The application developed solved the primary problem associated with the lifecycle cost analysis of a product: it accounted for all costs (e.g., environmental costs such as ecological costs and health costs associated with emissions) of the activity. A lifecycle cost analysis …

Ultrasound To Decontaminate Organics In Dredged Sediments, Kanya Veerawat

Theses

In this research, it was attempted to decontaminate and separate dredged sediments contaminated with organic compounds by the application of ultrasound energy coupled with sub-atmospheric pressures. The decontamination and separation of contaminated sediments was achieved by integrated two processes. For Process 1, ultrasound energy was used to decontaminate the sandy fraction in dredged sediments, and sub-atmospheric pressure was used to separate and remove fines. For Process 2, ultrasound was again used to decontaminate fines with bulk fluid, and sub-atmospheric pressure was used to remove the contaminants with water. Process 1 was evaluated and found to have four variables contributing to …

Effect Of Inhibitor On Electrochemical Behavior Of 1cr18 Stainless Steel In Acidic Solution Under Friction, Jin-Ping Xiong

Journal of Electrochemistry

The electrochemical behavior of 1Cr18 stainless steel had been studied using a reciprocating triboelectrochemical equipment under friction in 0.2 mol/L H₂SO₄ solution with and without addition of thiourea, the frictionized surface of 1Cr18 stainless steel had been examined by the SEM, XPS and IR. The results showed that the loss rate of 1Cr18 stainless steel in the solution could be reduced by addition of thiourea. The adsorption of thiourea on the surface of 1Cr18 stainless steel prohibited the oxidization of Cr³⁺ to form Cr(Ⅵ) and formation of passive film consisting of CrO₄^2- or/and Cr(Ⅵ), …

Z-Protected Glutamic Acid-Based Biodegradable Thermoplastic And Thermosetting Polyesters: Synthesis And Characterization, R. M. Tadros, Hossein Noureddini, Delmar C. Timm

Papers in Biomaterials

Biodegradable polymers were formed from N-benzyloxycarbonyl-L-glutamic acid with the comonomers ethylene glycol, diglycidyl ether of 1,4-butanediol, and diglycidyl ether of bisphenol A. The three polymers were a linear and a cross-linked heterochain polyester and a cross-linked polyester that contained aromatic units within its network chains. The thermoplastic resin and the soluble fractions for the thermosetting resins were characterized by gel permeation chromatography. Conversions for carboxylic acid were determined by titrations. A quality, 22,000 molecular weight thermoplastic resin was formed. The two thermosets were cured past their gel points. Gelation analysis revealed that the relative rate constants for the sequential oxirane/acid …

Membrane Process For Biological Treatment Of Contaminated Gas Streams, Sarina J. Ergas, Leslee Shumway, Mark W. Fitch, Jeffrey J. Neemann

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A Hollow Fiber Membrane Bioreactor Was Investigated for Control of Air Emissions of Biodegradable Volatile Organic Compounds (VOCs). in the Membrane Bioreactor, Gases Containing VOCs Pass through the Lumen of Microporous Hydrophobic Hollow Fiber Membranes. Soluble Compounds Diffuse through the Membrane Pores and Partition into a VOC Degrading Biofilm. the Hollow Fiber Membranes Serve as a Support for the Microbial Population and Provide a Large Surface Area for VOC and Oxygen Mass Transfer. Experiments Were Performed to Investigate the Effects of Toluene Loading Rate, Gas Residence Time, and Liquid Phase Turbulence on Toluene Removal in a Laboratory-Scale Membrane Bioreactor. Initial …

Modeling The High-Speed Switching Of Far-Infrared Radiation By Photoionization In A Semiconductor, Thomas E. Wilson

Physics Faculty Research

Data from an earlier study [T. Vogel et al., Appl. Opt. 31, 329 (1992)] on the subnanosecond switching of 119-μm radiation in high-resistivity silicon by pulsed UV laser radiation, is compared with a refined one-dimensional numerical multilayer model accounting for the generation, recombination, and diffusion of the free carriers on the resulting far-infrared optical properties of the silicon. The inclusion of recent measurements for carrier-density and temperature-dependent transport parameters leads to improved agreement between experiment and theory.

Santa Clara Magazine, Volume 41 Number 1, May 1999, Santa Clara University

Santa Clara Magazine

8 - A BRIDGE BETWEEN WORLDS By President PaulL. Locatelli, S.J. 'Go. President Locatelli examines the value of service learning for students, the University, and America's social fabric.

12 - A GIANT ARTIST By Ann Granning Bennett. Auguste Rodin's sculptures are now on view at the de Saisset Museum. The question is: How do high-profile art shows like this one come about?

18 - ARIZONA'S DIPLOMATIC TOP COP By Tamara Straus. Janet Napolitano ' 79 , Arizona's newly elected attorney general , discusses the challenges of public office as well as politics, ethics, and fighting crime.

Bs News

Building Services Engineering

No abstract provided.

Culture And The Management Of Advanced Automation: An Analysis Of Two Airlines, Surendra Cudah Ratwatte

Master's Theses - Daytona Beach

The purpose of this study was to investigate the relationship between National, Organizational and Professional Cultures and the attitudes toward managing advanced automation among the flightcrew of two international airlines. The Flight Management Attitudes Questionnaire developed by the University of Texas was utilized to determine the attitudes and perceptions held by airline pilots of various nationalities who fly late model Airbus and Boeing airliners. A census survey was conducted at the crew bases of the two airlines, one in the Middle East and other in South Asia. A total of 230 completed surveys were received. Chi Square analysis was used …

Interval Matching And Control For Hexahedral Mesh Generation Of Swept Volumes, Jason F. Shepherd

Theses and Dissertations

Surface meshing algorithms require certain relationships among the number of intervals on the curves that bound the surface. Assigning the number of intervals to all of the curves in the model such that all relationships are satisfied is called interval assignment. Volume meshing algorithms also require certain relationships among the numbers of intervals on each of the curves on the volume. These relationships are not always captured by surface meshing requirements. This thesis presents a news technique for automatically identifying volume constraints. In this technique, volume constraints are grouped with surface constraints and are solved simultaneously. A sweepable volume has …

Genetic Engineering Of Wood Color In Plants, Vincent Lee C. Chiang, Chung-Jui Tsai, Gopi K. Podila

Michigan Tech Patents

The invention relates to genetically engineering the wood color of woody plants by incorporation of the lignin pathway gene O-methyltransferase into the genome of the plants.