Thermal transitions in surfactant-based lyotropic liquid crystals

Abstract

The thermoluminescence (TL) of undoped and Dy 3+ doped ZrO 2 nanocrystals under ?-ray irradiation is reported. The TL glow curves are the result of the overlapping of four TL peaks produced partly by the intrinsic defect of highly asymmetrical monoclinic structure and partly due to defects produced during the synthesis process. The introduction of dopant ions induces changes in the glow curve due to the enhancement of high temperature peaks intensity. The results show that both undoped and doped ZrO 2 nanocrystalline phosphor present good TL efficiency as well as good dose response which qualify them as a potential ?-ray dosimeter. Copyright " 2008 American Scientific Publishers ALL rights reserved.",,,,,,"10.1166/jnn.2008.021",,,"http://hdl.handle.net/20.500.12104/45347","http://www.scopus.com/inward/record.url?eid=2-s2.0-58149296364&partnerID=40&md5=b19a8207b974732759c0c364fda76174

http://ovidsp.ovid.com/ovidweb.cgi?T=JS&CSC=Y&NEWS=N&PAGE=fulltext&D=prem&AN=19205215",,,,,,"12",,"Journal of Nanoscience and Nanotechnology",,"6419

6424",,"8",,"Scopus

WOS

MEDLINE",,,,,,"?-irradiation; Dosimetry; Dy 3+; Nanocrystals; Phosphor; Thermoluminescence; ZrO 2",,,,,,"Thermoluminescence properties of undoped and Dy 3+ doped ZrO 2 nanophosphor under -ray irradiation",,"Article" "47121","123456789/35008",,"Schulz, P.C., Facultad de Ciencias Químicas, Universidad de Guadalajara, Boul M. García Barragan #1451, Guadalajara, JAL 44430, Mexico; Puig, J.E., Facultad de Ciencias Químicas, Universidad de Guadalajara, Boul M. García Barragan #1451, Guadalajara, JAL 44430, Mexico; Barreiro, G., Departamento de Quimica, Centro de Investigación y Estudios Avanzados, Apdo. Postal 14-740, Mexico D.F. 07000, Mexico; Torres, L.A., Departamento de Quimica, Centro de Investigación y Estudios Avanzados, Apdo. Postal 14-740, Mexico D.F. 07000, Mexico",,"Schulz, P.C.

Puig, J.E.

Barreiro, G.

Torres, L.A.",,"1994",,"The state of water and several thermal transitions were examined in several surfactant/water lyotropic liquid crystalline systems. The surfactants studied were Aerosol OT (AOT), didodecyldimethylammonium bromide (DDAB), dioctadecyldimethylammonium bromide (DODAB) and M-decylphosphonic acid (DPA). In the AOT/water system, three types of water were detected: "bulk-like" water, interfacial water and hydration water (about six molecules of water per molecule of AOT). This system does not exhibit the gel-liquid-crystal transition, probably because the branched, short tails of AOT do not allow for crystallization upon cooling because of steric hindrance. In the DDAB/water and DODAB/water systems, only bulk-like water and two molecules of hydration water per molecule of surfactant were observed. The gel-liquid-crystal transition was detected at 15°C for DDAB and at 50°C for DODAB. In the DPA/water system, only bulk-like water was seen. The gel-liquid-crystal transition for this surfactant was detected at about 12°C. " 1994.