Search

A compact pulsed eddy current testing probe is being developed for the online dilation measurement of test specimens, examined in the high-temperature environment of material testing reactors. The probe has to be canned with metallic clad to protect it from the corrosive sodium-potassium coolant medium present in the material testing reactor. Electromagnetic modelling of the probe was carried out to compute the distribution of time-dependent eddy current density in the vicinity of the probe. It is understood that the slope of the pulsed eddy current signals in the specific time zone where the lift-off point of intersection occurs show a good correlation to the distance between the face of the probe and the test specimen. This paper discusses the experimental study of employing different measurement methodologies at room temperature with the canned pulsed eddy current probe to evaluate its feasibility for dilation measurement. It is observed that a phenomenon of a divergence of signals, akin to the lift-off point of intersection, occurs just after the transient part of the pulsed eddy current signals. Slope analysis of these diverging pulsed eddy current signals was carried out for characterisation of the probe in the air medium as well as the metallic medium present in the gap between the probe face and the test specimen. [ABSTRACT FROM AUTHOR]

Summary: The fire behavior of various large samples polymers assemblies is an under‐researched topic. In fire risk assessment, the resultant heat release rate of burning different combustibles has to be known. To highlight interactions between components, 2 types of configurations were tested: juxtaposed and layered materials, using a specific radiant panel setup. For juxtaposed assemblies, results indicated that the more flammable component acted as an accelerator for the global combustion kinetics. For layered assemblies, 2 main phenomena were evidenced: the front material acted as a shield delaying the combustion of the backside material and the presence of a backside material induced a thermal thickening that slowed down the combustion of the front material. The experimental burning behaviors of the assembly were compared with a simulated one calculated from the superposition principle. This method was described by introducing a time offset and/or a slowdown factor in the model, confirmed with the use of different assemblies. [ABSTRACT FROM AUTHOR]

The light-water one-rod equipment for loss-of-coolant accident (LOCA) experimental investigation (LORELEI) device, one of the experiments of the future experimental nuclear reactor Jules Horowitz of Commissariat à l’Energie Atomique et aux Energies Alternatives, will be dedicated to the study of the LOCA. For a better understanding of the temperature conditions during a LOCA, the surface temperature of the fuel cladding has to be monitored. For this purpose, we are designing a noncontact temperature measurement device based on multispectral pyrometry, adapted to the extreme conditions of LORELEI. In this paper, we present a radiative transfer model, taking into account the direct flux from the measured surface and contributions from the surroundings, to simulate the impact of high-temperature surroundings on the temperature estimated using the multispectral radiation thermometry (MRT) method. The hypothesis of a constant emissivity profile in the spectral ranges of calculation is used to estimate the surface temperature. Experimental pyrometry measurements are performed on Zircaloy-4 and Inconel surfaces in high-temperature surroundings to validate the model. As in LORELEI, an optical fiber is used to carry the infrared thermal flux from the cladding to the spectrometer. Thermocouples are used to give a reference temperature and to provide a complete temperature monitoring of the device. A temperature difference is observed between the “true” cladding temperature and the MRT temperature estimation, when the temperature of the surroundings is between 50 °C and 150 °C below the cladding temperature, and this difference increases with the cladding temperature. This provides a correction value to apply on the temperature estimation to approach the real cladding temperature. [ABSTRACT FROM AUTHOR]

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The flammability of various flame-retarded formulations containing different hydrated mineral fillers and/or phosphorous compounds and/or carbon nanotubes has been investigated using both a cone calorimeter and a pyrolysis combustion flow calorimeter (PCFC). A method was proposed to evaluate the barrier effect of the flame-retardant additives. This method is based on the fact that the PCFC is non-sensitive to physical flame-retardant effects whereas both chemical and physical phenomena have a great effect on cone calorimeter results. Therefore, normalized peak of heat release rate (pHRR) values obtained with both techniques do not always show a good correlation. It was highlighted that the mismatch between both pHRR results was related to the formation of a protective layer during combustion. Protective layers have been evidenced independently by visual observations. Thus, it is proposed that the magnitude of the deviation from a perfect correlation between cone calorimeter and PCFC pHRRs could be used to quantify the magnitude of barrier effect. Although the results obtained from different fire tests are generally not correlated, such an approach based on the complementarity of different techniques appears more relevant despite of its empirical nature. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Design: The aim of the programme was to ultimately affect public health practice and policy in the Kingdom of Cambodia and Lao People's Democratic Republic (Lao PR) by training key health professionals to conduct tobacco control research. Setting: Encouraged by the World Health Organization's Framework Convention on Tobacco Control, a global partnership formed to build effective leadership to develop and guide national tobacco control agendas. The partners were the Ministries of Health (Cambodia and Lao PDR), non-government organisations (Adventist Development and Relief Agency in Cambodia and Laos) and an academic institution (Lama Linda University, Lama Linda, California, USA). Subjects: 16 health professionals, 10 from Cambodia and 6 from Lao PDR, were selected by local advisory committees to enter a two-year, intensive tobacco research graduate certificate and research training programme. Intervention: We developed a "Global Tobacco Control Methods" (GTCM) 28 unit certificate programme that was offered in five sessions from September 2003 to September 2005 at the National Institute of Public Health, Phnom Penh, Cambodia. As part of their coursework, the 16 trainees actively participated in the development and implementation of two research projects. In the first project, "Healthy Doc Healthy Patient" (HDHP), trainees adapted an existing, self-administered questionnaire designed to assess health practices and beliefs of medical students in Cambodia and Lao PDR. The second project involved the design of a national prevalence of tobacco use and health beliefs study in Cambodia using a multi-stage, cluster sample method. Trainees were sponsored to attend and present at international tobacco control conferences to enhance their awareness of the tobacco epidemic. Results: As of September 2005, 14 trainees (8 from Cambodia and 6 from Lao PDR) completed the courses in the GTCM certificate programme. The HDHP study sampled four medical school classes (years 3, 4, 5 and 6) in bath Cambodia (n = 330, 71.1% response rate) and Lao PDR (n = 386, 87.3% response rate). As port of the Cambodian adult tobacco prevalence study in Cambodia, 13 988 adults (ages ≥ 18 years) were interviewed from all 22 provinces during the summer of 2005. Over the two years, more than half of the trainees participated substantially in local and regional tobacco control and research activities. Programme challenges included the trainees' limited English language and computer proficiency skills, bath of which improved during the two years. Conclusions: With the successful completion of the certificate programme, the remaining two years of the grant will be used to prepare the trainees for positions of leadership within their Ministries of Health and agencies to implement effective tobacco control policies based on locally-derived research findings. [ABSTRACT FROM AUTHOR]

Context: Tobacco use is the leading preventable cause of death in the United States. And yet only 21% of practicing physicians claim they received adequate training to help their patients stop smoking.Objective: To assess the content and extent of tobacco education and intervention skills in US medical schools' curricula.Design: A survey with 13 multiple-response items on tobacco education. Survey questions were based on the recommendations of the Agency for Health Care Policy and Research and the National Cancer Institute Expert Panel. The Liaison Committee on Medical Education included 4 of these items in a modified form on the 1997 annual questionnaire.Setting: One hundred twenty-six US medical schools.Participants: Surveys were obtained from 122 associate deans for medical education (98.6%).Main Outcome Measures: Curriculum content in basic science and clinical science, elective or required clinical experience, hours of instruction, and resource materials.Results: Inclusion of all 6 tobacco curricula content areas recommended by the National Cancer Institute and the Agency for Health Care Policy and Research was higher in basic science (63/115 [54.8%]) than in clinical science (5/115 [4.4%]). Most medical schools (83/120 [69.2%]) did not require clinical training in smoking cessation techniques, while 23.5% (27/115) offered additional experience as an elective course. Thirty-one percent (32/102) of schools averaged less than 1 hour of instruction per year in smoking cessation techniques during the 4 years of medical school. A minority of schools reported 3 or more hours of clinical smoking cessation instruction in the third (14.7%) and fourth (4.9%) years.Conclusions: A majority of US medical school graduates are not adequately trained to treat nicotine dependence. The major deficit is the lack of smoking cessation instruction and evaluation in the clinical years. A model core tobacco curricula that meets national recommendations should be developed and implemented in all US medical schools. [ABSTRACT FROM AUTHOR]

Abnormalities in the dopaminergic reward pathways have frequently been implicated in substance abuse and addictive behaviors. Recent studies by Self and coworkers have suggested an important interaction between the dopamine D[sub 1] and D[sub 2] receptors in cocaine abuse. To test the hypothesis that the DRD1 gene might play a role in addictive behaviors we examined the alleles of the Dde I polymorphism in three independent groups of subjects with varying types of compulsive, addictive behaviors — Tourette syndrome probands, smokers and pathological gamblers. In all three groups there was a significant increase in the frequency of homozygosity for the DRD1 Dde I 1 or 2 alleles in subjects with addictive behaviors. The DRD1 11 or 22 genotype was present in 41.3% of 63 controls and 57.3% of 227 TS probands (P = 0.024). When 23 quantitative traits were examined by ANOVA those carrying the 11 genotype consistently had the highest scores. Based on these results, we examined the prevalence of the 11 genotype in controls, TS probands without a specific behavior, and TS probands with a specific behavior. There was a progressive, linear increase, significant at α ≤ 0.005 for scores for gambling, alcohol use and compulsive shopping. Problems with three additional behaviors, drug use, compulsive eating and smoking were significant at α ≤ 0.05. All six variables were related to addictive behaviors. In a totally separate group of controls and individuals attending a smoking cessation clinic, and smoking at least one pack per day, 39.3% of the controls versus 66.1% of the smokers carried the 11 or 22 genotype (P = 0.0002). In a third independent group of pathological gamblers, 55.8% carried the 11 or 22 genotype (P = 0.009 vs the combined controls). In the TS group and smokers there was a significant additive effect of the DRD1 and DRD2 genes. The results for both the DRD1 and DRD2 genes, which have opposing effects on cyclic AMP, were consistent with... [ABSTRACT FROM AUTHOR]