ABSTRACT
Insensitive munitions formulations that include 3-nitro-1,2,4-triazol-5-one (NTO) are replacing traditional explosive compounds. While these new formulations have superior safety characteristics, the compounds have greater environmental mobility, raising concern over potential contamination and cleanup of training and manufacturing facilities. Here, we examine the mechanisms and products of NTO photolysis in simulated sunlight to further inform NTO degradation in sunlit surface waters. We demonstrate that NTO produces singlet oxygen and that dissolved oxygen increases the NTO photolysis rate in deionized water. The rate of NTO photolysis is independent of concentration and decreases slightly in the presence of Suwannee River Natural Organic Matter. The apparent quantum yield of NTO generally decreases as pH increases, ranging from 2.0 × 10-5 at pH 12 to 1.3 × 10-3 at pH 2. Bimolecular reaction rate constants for NTO with singlet oxygen and hydroxyl radical were measured to be (1.95 ± 0.15) × 106 and (3.28 ± 0.23) × 1010 M-1 s-1, respectively. Major photolysis reaction products were ammonium, nitrite, and nitrate, with nitrite produced in nearly stoichiometric yield upon the reaction of NTO with singlet oxygen. Environmental half-lives are predicted to span from 1.1 to 5.7 days. Taken together, these data enhance our understanding of NTO photolysis under environmentally relevant conditions.
ABSTRACT
Introducción y Objetivo: El presente artículo describe el diseño, construcción de un sistema electrónico de adquisición de datos portátil para un sensor de fuerza de mordida con una capacidad de 200 Kg. que previamente fue desarrollado (Gnatodinamómetro-GIB), con el fin de almacenar datos de fuerza oclusal en personas, las cuales, son identificadas por su nombre y un código de 4 dígitos. Materiales y Métodos: El sistema está configurado para almacenar registros de mordida de hasta 60 personas, donde cada uno de los registros puede contener hasta 6 medidas de fuerza oclusal. La información es almacenada en memoria y posteriormente puede ser descargada a un computador mediante el puerto RS232, a partir de una aplicación de software desarrollada en Borland-Delphi. Los archivos descargados están en formato de texto plano (*.txt), lo cual facilitó su análisis mediante una herramienta convencional de hoja de cálculo. Resultados: Se obtuvo un artefacto electrónico portátil, con unas medidas de 1 9x14x5 cm y con un peso de 528 gramos. La calibración del Gnatodinamómetro arrojó un coeficiente de determinación R2 de 0.9997 y una resolución de 150 gr. En la prueba de reproducibilidad en pacientes, se encontró que las medidas de fuerza oclusal para cada una de las zonas evaluadas: molar izquierda, molar derecha e incisivos, se obtuvo un coeficiente de correlación intraclase que osciló entre 0.9 y 0.97. Conclusión: Se desarrolló un sistema versátil y liviano, el cual pudo ser transportado fácilmente hacia el lugar donde se encontraban las personas que fueron sometidas a pruebas de fuerza de mordida, que a su vez, garantizó la seguridad en el momento de adquirir y almacenar la información.
Introduction and Objetive: This study describes the design and construction of an electronic system for a bite force sensor data acquisition, (Gnathodynamometer, GIB), that had been previously developed with the aim of storing human oclusal force data. The subjects are identified by their name and a 4 digit codeo. Materials and Methods: The system was developed to store bite force records of up to 60 people with 6 measurements per individual. The information can be stored in a memory system and can be downloaded to any computer by means of an RS232 port by means of a software application that was developed on a Borland-Delphi platform. The files are then formatted by the software application to a plain text (*.txt) which facilitates the data analysis by conventional tools. Results: A portable electronic device was obtained with the following measures: 1 9x14x5 cm and 528 gr of weight. The Gnathodynamometer calibration showed a determination coefficient R2 of 0.9997 and a resolution of 150gr. The reproducibility test in patients, showed an intraclass correlation coefficient for bite force between 0.9 and 0.97. Conclusion: A light and easy to operate system was developed that could be taken to the schools were bite force data gathering is required to be done in a secure an efficient way.
