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Preliminary Survey of Air Quality and Related Health Studies Conducted in the Vicinity of Ground Zero

Preliminary Survey of Air Quality and Related Health Studies Conducted in the Vicinity of Ground Zero

Date: December 2002
Creator: National Science and Technology Council (U.S.). Air Quality Research Subcommittee.
Description: This document represents the first survey by the research community of the impact of the collapse of the World Trade Center in New York on air quality and public health in lower Manhattan.
Contributing Partner: UNT Libraries
PREMIS Event Service

PREMIS Event Service

Date: June 9, 2011
Creator: Phillips, Mark Edward; Schultz, Matt & Nordstrom, Kurt
Description: This presentation discusses the PREMIS Event Service. The University of North Texas (UNT) Libraries has created a digital library infrastructure that is designed using the Curation Micro Services methodology for building repositories. Based on modular components designed for reuse and re-configuration the authors propose a general-purpose preservation event logging system using the PREMIS Event and Agent data model.
Contributing Partner: UNT Libraries
PREMIS Event Service

PREMIS Event Service

Date: June 9, 2011
Creator: Phillips, Mark Edward; Schultz, Matt & Nordstrom, Kurt
Description: This paper discusses the PREMIS Event Service. The University of North Texas (UNT) Libraries have created a digital library infrastructure that is designed using the Curation Micro Services methodology for building repositories. Based on modular components designed for reuse and re-configuration the authors propose a general-purpose preservation event logging system using the PREMIS Event and Agent data model. An example implementation developed with the Django Web framework and employing RESTful design patterns with the Atom Publishing Protocol is described.
Contributing Partner: UNT Libraries
Preparation and Characterization of a Treated Montmorillonite Clay and Epoxy Nanocomposite

Preparation and Characterization of a Treated Montmorillonite Clay and Epoxy Nanocomposite

Date: December 2000
Creator: Butzloff, Peter Robert
Description: Montmorillonite reinforced polymers are a new development in the area of nanocomposite materials. Since reinforcement of epoxy is important to the development of high strength adhesives and composite matrices, the introduction of montmorillonite to epoxy is of interest. Compositional effects on epoxy reactivity, on molecular relaxation, and on mechanical properties were investigated. Change in reactivity was determined by Differential Scanning Calorimetry. Tensile properties at room temperature indicated improved modulus and retention of strength of the epoxy matrix but a decreased elongation to failure. Depression of dry nanocomposite glass transition was observed for nanocomposites beyond 5% by weight montmorillonite. Samples that were saturated with water showed lower moduli due to the epoxy matrix. The greatest moisture absorption rate was found at 7%, the least at 3%.
Contributing Partner: UNT Libraries
Preparation and characterization of praseodymium oxide films and powders.

Preparation and characterization of praseodymium oxide films and powders.

Access: Use of this item is restricted to the UNT Community.
Date: May 2004
Creator: Shang, Yajuan
Description: Nanocrystalline praseodymium oxide films have been successfully generated on stainless steel substrates. The electrochemical deposition was performed in the cathode compartment of a divided electrochemical cell with a regular three-electrode configuration. The green films obtained by electrodeposition were then annealed at high temperatures for 1-3 hours. X-ray diffraction revealed the fluorite structure of Pr6O11 and the crystallite size was calculated. X-ray photoelectron spectroscopy was employed to study the composition of the oxide films and also the oxidation state of Pr. Scanning electron microscopy was utilized to study the surface texture and microstructure of deposits. Fourier transform infrared spectrometery was used to investigate the composition of the films. The effects of different conditions on the green films were also studied such as different pH values of the electrolyte solution, different deposition modes, different supporting electrolytes and different applied current densities. Sintering experiments were conducted to investigate the properties of the green films. Praseodymium oxide powders were also successfully prepared by combining electrochemical methods with sintering processes. The praseodymium oxide powders were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The crystallite sizes of the powders were evaluated.
Contributing Partner: UNT Libraries
The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network.

The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network.

Date: December 2001
Creator: Zhou, Bo
Description: Polymer hydrogel films change their properties in response to environmental change. This remarkable phenomenon results in many potential applications of polymer hydrogel films. In this thesis colored thermo-sensitive poly(N-isopropylacrylamide) (PNIPAAm) hydrogel film was prepared by firstly synthesizing polymer latex and secondarily crosslinking the nanoparticles and casting the polymers onto glass. The shape-memory effect has been observed when changing the environmental temperature. The temperature-dependent of turbidity of polymer hydrogel film was measured by HP UVVisible spectrophotometer. This intelligent hydrogel might be used in chemomechanical systems and separation devices as well as sensors. Polymer adsorption plays an important role in many products and processes. In this thesis, surfactant-free three-dimensional polystyrene (PS) nanoparticle network has been prepared. The infrared spectroscopy and solubility experiment are performed to prove the crosslinking mechanism, also the BET method was used to measure the adsorption and desorption of polystyrene network. The BET constant (C) is calculated (C=6.32). The chemically bonded polymer nanoparticle network might have potential applications as catalyst or used for chromatographic columns.
Contributing Partner: UNT Libraries
Preparation and Stereochemistry of Reactive Intermediates Containing a Silicon-Carbon Double Bond

Preparation and Stereochemistry of Reactive Intermediates Containing a Silicon-Carbon Double Bond

Date: December 1991
Creator: Uang, Shinian
Description: 1,1-Dimethyl-2-neopentylsilene reacted with the N-methylimine of benzophenone to give 1,2,2-trimethyl-3- neopentyl-4,4-diphenyl-l-aza-2-silacyclobutane, I, and 2,3,4,4a-tetrahydro-2,3,3-trimethyl-1-phenyl-4-neopentyl-2- aza-3-silanephthalene, II, in 35% and 20% yields, respectively. Compounds I and II did not serve as thermal silene precursors. Heating I and II to over 280°C did not yield 1,3-disilacyclobutanes. In the presence of 2,3- dimethyl-1,3-butadiene typical silene products were not obtained. However, I and II reacted rapidly with methanol at room temperature to give the ring-opened products (E)-2- methoxy-2,5,5-trimethyl-2-silahex-3-ene, III, 1,1- diphenyldimethylamine, IV, and 2-methoxy-2,5,5-trimethyl-3- (N-methylaminodiphenyl) methyl-2-silahexane, V.
Contributing Partner: UNT Libraries
Preparation is Key: Lessons Learned from an ERMS Implementation

Preparation is Key: Lessons Learned from an ERMS Implementation

Date: June 2013
Creator: Enoch, Todd
Description: This presentation discusses lessons learned from an Electronic Resource Management System (ERMS).
Contributing Partner: UNT Libraries
Preparation of 4-Amino-3-Hydrazino-5-Methyl-s-Triazole Dihydrochloride and Condensation Products

Preparation of 4-Amino-3-Hydrazino-5-Methyl-s-Triazole Dihydrochloride and Condensation Products

Date: August 1965
Creator: Westmoreland, Thomas D.
Description: The procedure of Takimoto, Denault, and Hotta was followed in order to prepare 4-amino-3-hydrazino-5-methyl-s-triazole hydrochloride (II) and its precursor, triamino-guanidine hydrochloride (I).
Contributing Partner: UNT Libraries
The Preparation of Academic Library Administrators

The Preparation of Academic Library Administrators

Date: December 2012
Creator: Hoffman, Starr
Description: The purpose of this quantitative study was to determine the preparation methods experienced by academic library deans and which methods they perceived to be most valuable. Rosser, Johnsrud, and Heck (2000, 2003) defined the theoretical constructs of effective academic leadership upon which this study is based. The instrument—a modified version of Greicar's (2009) Professional Preparation of Academic Deans Questionnaire—was administered online. The population was the chief administrators of academic libraries in the United States; there were 749 usable responses for a 30.4% response rate. Respondents were primarily female (61.7%), White non-Hispanic (90.0%), and born in the United States (95.7%), with a mean age of 56.4 (5.9% < 40, 11.0% > 65). The largest minority group was Black, non-Hispanic (3.9%). Many respondents held multiple advanced degrees; 90.0% held an MLS, 45.8% held a subject master's, and 18.8% held a doctorate. The instrument measured academic library deans' perceived value of various preparatory methods (formal and informal mentoring, on the job training, conferences or seminars, advanced degrees beyond the MLS, and training programs). The methods were tested for perceived effectiveness with Rosser, Johnsrud, and Heck's (2000, 2003) theoretical constructs of academic leadership. Each preparation method was measured using eight item-level variables and summed ...
Contributing Partner: UNT Libraries