Study of L-Glutamic Acid in Solid State for its Possible Use as a Gamma Dosimeter at Different Temperatures (77, 195 and 295 K)

A L MELÉNDEZ-LÓPEZ1,2, J CRUZ-CASTAÑEDA1,2, A PAREDESARRIAGA1,3, A NEGRÓN-MENDOZA1*AND S RAMOS-BERNAL1

1Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, UNAM

2 Programa de Maestría y Doctorado en Ciencias Químicas, Universidad Nacional Autónoma de México, UNAM

3 Facultad de Ciencias, Universidad Nacional Autónoma de México, UNAM

 *Email: negrón@nucleares.unam.mx

Abstract The experimental response of the dosimeter as a function of the irradiation temperature plays an important role, and this effect has consequences in the practical applications of dosimetry. In this work, L-glutamic acid (2-aminopentanedioic acid) is proposed to be a good response, easy to handle, and a cheap gamma dosimeter. For this purpose, polycrystalline samples were irradiated with gamma rays at 77, 195, and 295 K and doses in the kiloGray range (43–230 kGy). The potential use of the glutamic acid system as a chemical dosimeter is based on the formation of stable free radicals when the amino acid is exposed to ionizing radiation. The observed species in these experiments were attributed to deamination and decarboxylation reactions that were studied using electron spin resonance (ESR). The results indicate that the analysis generates a linear response as the irradiation dose increases in a reliable range for industrial and research purposes at three different temperatures.

DOI: https://doi.org/10.15415/jnp.2017.51017

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/877/1/51017_JNP_MELENDEZ%20-%20NEGRON.pdf

Sperm Hyperactivation and Capacitation Induced By Light Stimuli in Cryopreserved Semen

V. SOTO1 , M.A. FUENTES1 , G. NAVIDAD1 , R.N. MEZA1 , L.A. MANDUJANO2 , A.G. SALAZAR1 , C. FERNÁNDEZ3 , C. GARCÍA4 ,Y.E. FELIPE-PÉREZ4 AND D. OSORIO-GONZÁLEZ1*.

1 Laboratorio de Biofísica Molecular de la Facultad de Ciencias. Universidad Autónoma del Estado de México.

2 Laboratorio de Diseño y Modelado Biofísico Molecular de la Universidad Mexiquense, S. C.

3 Clinica Fertilidad “Biología de la Reproducción” del Hospital Materno Perinatal “Mónica Pretelini Sáenz” Adscripción

4 Laboratorio de Biología de la Reproducción de la Facultad de Medicina Veterinaria y Zootecnia. Universidad Autónoma del Estado de México

Email: dog@uaemex.mx

DOI: https://doi.org/10.15415/jnp.2017.51015

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/875/1/51015_JNP_D.%20Osorio.pdf

Implementation of a Low Cost For Internal Dosimetry Radiological Survey of Ionization Radiation Exposed Workers In Nuclear Medicine Services

J VALLE1,2*, A ANGELES2 AND T GARCÍA2

1 Facultad de Medicina, Universidad Autónoma del Estado de México, Paseo Tollocan esq. Jesús Carranza, Toluca, Estado de México, Mexico.

2 Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca, La Marquesa, Ocoyoacac 52750, Estado de Mexico, Mexico.

1,*Email: jvaller@outlook.com

Abstract Because the nature of the routine activities carried on in nuclear medicine services, where several not sealed radioactive sources are used, the occupational personal exposed to ionization radiation (POE) is exposed to both, internal and external radioactive contamination and direct radiation also. The most important radioisotope from the point of view of radiological risk in such Nuclear Medicine Services (NMS) is the 131I. The Mexican official regulatory organization in radiological and nuclear safety: Comisión de Seguridad Nuclear y Salvaguardias (CNSNS) specify, as a requirement in the operation license of Nuclear Medicine Services the mandatory of internal and external dosimetry survey of POE. The external dosimetry survey is normally carried out but the internal dosimetry survey is not easy to do, because internal dosimetry systems are too expensive and in Mexico there are only three organizations (CFE-CLV, ININ, CNSNS) where there are these systems but they aren´t easily available for the Nuclear Medicine Services. Because that before fact, we propose a single, and low cost system (SLCS) to survey the internal dosimetry of POE. This system is based in a scintillation NaI(Tl) 2x2 detector and a common radiation monitor tipically used in the routine radiation and contamination measures, with a minimal infrastructure investment. This system is numerical calibrated with Montecarlo method, and compared with an well established commercial System being a good function corresponding. This system is easy to implementing in any nuclear medicine to complain the requirement of operation license in the internal dosimetry POE survey.

DOI: https://doi.org/10.15415/jnp.2017.51014

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/874/1/51014_JNP_Valle.pdf

Radiolysis of the Glycolaldehyde-Na+ Montmorillonite and Glycolaldehyde-Fe3+Montmorillonite Systems in Aqueous Suspension under Gamma Radiation Fields: Implications in Chemical Evolution

J. CRUZ-CASTAÑEDA1, 2, A. L. MELÉNDEZ-LÓPEZ1, 2, S. RAMOS-BERNAL1 AND A. NEGRÓN-MENDOZA1*

1Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, UNAM. Cd. Universitaria, A. P. 70-543, 04510 México, D. F. México

2 Programa de Maestría y Doctorado en Ciencias Químicas, UNAM. Cd. Universitaria, A. P. 70-543, 04510 México, D. F. México

* Email: negron@nucleares.unam.mx

Abstract The stability and reactivity of organic molecules with biological and pre-biological significance in primitive conditions are of paramount importance in chemical evolution studies. Sugars are an essential component in biological systems for the different roles that they play in living beings. The objective of the present work is to study the gamma radiolysis of aqueous solutions of glycolaldehyde, the simplest sugar and aqueous suspensions of glycolaldehydeNa+ -montmorillonite and glycolaldehyde-Fe3+Montmorillonite. Our results indicate that the radiolysis of the aqueous solutions of glycolaldehyde (0.03M), oxygen free, mainly produce the linear dimer known as eritriol (122 g/mol) and a sugar-like compound with six carbon atoms (180 g/mol). The experiments with the clay suspensions show that clays can adsorb glycolaldehyde and protect it from gamma irradiation. Additionally, it was observed that depending on the cation present in the clay, the percentage and the product (monomer or cyclic dimer) adsorption was different. In the case of Fe3+ Montmorillonite, this clay catalyzed the decomposition of glycolaldehyde, forming small amounts nonidentified products. The analysis of these systems was performed by ATRFTIR, UV spectroscopy, liquid chromatography (UHPLC-UV), and HPLC coupled to a mass spectrometry.

DOI: https://doi.org/10.15415/jnp.2017.51013

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/873/1/51013_JNP_Negrón-Mendoza.pdf

Thermoluminescent Characteristics of Li2 B4 O7 Doped with Mn2+ and Eu3+ Ions

P. TREJO-GARCÍA 1, E. CRUZ-ZARAGOZA3 , R. ACEVES2 , J. E. ESPINOSA1 , R. PALOMINO MERINO1*

1 Facultad de Ciencias Físico-Matemáticas, B. Universidad Autónoma de Puebla., Pue., Ciudad Universitaria, Puebla, Pue., México. P.O. Box 1067, C.P. 72001 México.

2 Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-088, 83190 Hermosillo Sonora, México.

3 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70- 543, 04510 Ciudad de México, México

1*Email: palomino@fcfm.buap.mx

Abstract 
Analysis of thermoluminescent properties were made for two samples; Li2 B4 O7 , Li2 B4 O7 :Mn2+:Eu3+. These samples were prepared by melt quenching method. The glow curves of the samples show two broad peaks at 160º C and 245 ºC, and a high peak at 130ºC for Li2 B4 O7 doped. The response of the materials were analyzed according to the doses (0.2-80 Gy), fading (0- 72 hours) and reproducibility of the experiment (10 times). To determine how the glow curve is formed, thermal bleaching for a dose of 5 Gy were made from room temperature to 300º C. Besides, X-ray diffraction patterns were recorded to identify the structure and grain size of the samples.

DOI: https://doi.org/10.15415/jnp.2017.51012

LINK: http://dspace.chitkara.edu.in/jspui/bitstream/1/872/1/51012_JNP_Merino.pdf