Neutron Beam Techniques Research Articles

Influence of a Novel Double Tempering Process on the Microstructure and Mechanical Properties of Cu-Alloyed Austempered Ductile Iron with Possible Nano (Micro)-Characterization Using Neutron Beam Techniques

In this paper, a novel method for the double heat treatment of ductile iron was applied. Ten sets of specimens (three specimens in each set) of ductile cast iron (DCI) containing 0.51% wt. Cu were prepared and converted to austenitic ductile iron. All specimens were austenitized at 850 °C for 60 min and annealed at 420 °C, 331 °C and 250 °C for 120, 68 and 30 min, respectively. Five sets of samples were then annealed at 500 °C for 60 min, creating a novel double heat treatment process for annealing. Finally, all specimens were slowly cooled in air at ambient temperature. Tensile strength, hardness and elongation were measured in all specimens to compare the specimens with and without subsequent tempering. A microstructural analysis was also performed, which showed that the microstructure changed for the specimens that were subsequently tempered with. The results show that specimens with subsequent tempering have slightly higher hardness, a small decrease in tensile strength and significantly higher elongation. In addition, specimens with subsequent tempering exhibit more uniform mechanical properties compared to specimens without subsequent tempering. The use of neutron beam techniques was proposed to further characterize the newly formed microstructure after subsequent tempering.

Analiza biomedicinskih materijala i delova - napredna nano(mikro)-karakterizacija tehnikama neutronskog snopa

The progress of the study of biomedical materials and devices, as well as their advancement, especially depend on the application of efficient characterization techniques to evaluate key physical parameters connected to performances, damage and quality. A main aim is to establish correct relationships between macroscopic functional properties and nano(micro)-characteristics. Numerous invasive biomedical devices, e.g., as planned to remain in the human body for the entire life of the patient, once implanted, operate in the ionic environment of the blood and in contact with the released substances and cells. The consequent effects must be added to the other aging factors: the dynamic stress of the pulsation is one of these effects and concerns the operational of self-expandable stents installed in arteries such as the carotid to correct stenosis. Neutron beam techniques are an excellent tool to study materials and parts of biomedical interest, contributing to solve important questions linked with the methodological restrictions of the analysis methods generally adopted: their results, complementarily, can help improving quality and functionality. This paper concerns the advanced nano(micro)-characterization of biomedical materials and parts by these non-destructive and non-invasive nuclear methods. Some examples related to the biological field are also mentioned. For applications in the biomedical and in the industrial sectors, the Rogante Engineering Office has developed particular methodological approaches and dedicated processing and treatment procedures.

A preliminary investigation on visualization of oscillating heat pipe with non-destructive test

Oscillating Heat Pipe (OHP) is a passive heat exchanger operating on two phase flow principle. As one of the newest members of the heat pipe family, OHP has a complicated operating mechanism of working fluid flow. OHP is a potential device, which can be used for saving energy and cost. Although, OHP is a promising two-phase heat transfer device with excellent performance, simple structure and low cost but its operational characteristic is still not clear yet and debatable. As one of the non-destructive test, neutron radiography uses neutron beam techniques to penetrate heavy materials while beam are absorbed by lighter materials. This method is very suitable for use in visualization technique of the two-phase flow of heat transfer device with hydrogen-based fluids. In this paper, the visualization method is coupled with thermocouple temperature measurement. Aluminium OHP with 12 turns has been manufactured and tested. The dimension of aluminium OHP is made fit with the neutron beam size. DI Water with filing ratio 35 % has been chosen as the working fluid for the close loop OHP. Three level of heating power was applied to the evaporator section of OHP. The result showed that this preliminary study could reveal the temperature fluctuation of the thermocouple data. The condensation and evaporation also can be observed adequately with this method.

IAEA ACTIVITIES SUPPORTING THE APPLICATIONS OF RESEARCH REACTORS IN 2013

As the underutilization of research reactors around the world persists as a primary topic of concern among facility owners and operators, the IAEA responded in 2013 with a broad range of activities to address the planning, execution and improvement of many experimental techniques. The revision of two critical documents for planning and diversifying a facility's portfolio of applications, TECDOC 1234 “The Applications of Research Reactors” and TECDOC 1212 “Strategic Planning for Research Reactors”, is in progress in order to keep this information relevant, corresponding to the dynamism of experimental techniques and research capabilities. Related to the latter TECDOC, the IAEA convened a meeting in 2013 for the expert review of a number of strategic plans submitted by research reactor operators in developing countries. A number of activities focusing on specific applications are either continuing or beginning as well. In neutron activation analysis, a joint round of inter-comparison proficiency testing sponsored by the IAEA Technical Cooperation Department will be completed, and facility progress in measurement accuracy is described. Also, a training workshop in neutron imaging and Coordinated Research Projects in reactor benchmarks, automation of neutron activation analysis and neutron beam techniques for material testing intend to advance these activities as more beneficial services to researchers and other users.

Neutron beam measurement of industrial polymer materials for composition and bulk integrity

Neutron beam techniques, among other non-destructive diagnostics, are particularly irreplaceable in the complete analysis of industrial materials and components when supplying fundamental information. In this paper, nanoscale small-angle neutron scattering analysis and prompt gamma activation analysis for the characterization of industrial polymers are considered. The basic theoretical aspects are briefly introduced and some applications are presented. The investigations of the SU-8 polymer in axial airflow microturbines—i.e. microelectromechanical systems—are presented foremost. Also presented are full and feasibility studies on polyurethanes, composites based on cross-linked polymers reinforced by carbon fibres and polymer cement concrete. The obtained results have provided a substantial contribution to the improvement of the considered materials, and indeed confirmed the industrial applicability of the adopted techniques in the analysis of polymers.

Feasibility Study for a Neutron-Based Investigation of Polymer Cement Concretes

Study of dense cements, ceramics and related materials such as cement stones, is significant to create novel advanced components for various types of buildings and structures. These materials can possess high functional properties and they can be adopted for various purposes, for instance as corrosion resistive coatings for cement constructions. In this paper, the investigability of polymer cement concretes by neutron beam techniques (NBT) and, in particular, the nano-scale characterization by small angle neutron scattering (SANS) of polymer cement concrete (PCC) samples made of Portland or aluminous cement with added γAl2O3 and redispersible dry polymer, are discussed. The main aims are to assess key parameters (e.g., porosity, fractal dimensions, size distribution, presence of cracks or open and closed pores) responsible of the materials' performance at the scale from 1 A to 100 A, as well as to expand the possibility of applications. NBT, among the other non-destructive diagnostics, are particularly unique in the complete analysis of industrial materials when supplying essential information. The results obtained by means of a neutron-based investigation can translate into the optimization of consistency and the design of operating conditions and procedures that support and enhance quality and safety levels. Various examples concerning the examinations of different kinds of cements are reported. This state-of-the-art stage indeed confirms the industrial applicability of NBT in completing the characterization of the considered materials.

Analytical techniques in art, archaeology and conservation science

This special issue of Analytical and Bioanalytical Chemistry is dedicated to the use of analytical techniques in the field of cultural heritage. It contains a selection from the contributions presented in Berlin during the TECHNART 2011 conference on non-destructive and microanalytical techniques in art and cultural heritage. The contributions to the conference covered a wide range of advanced X-ray, ion and neutron beam techniques with special emphasis on microanalysis [X-ray fluorescence (XRF), particle-induced X-ray emission (PIXE), X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray analysis] and confocal microscopy (3D micro-XRF, 3D micro-PIXE). Other contributions focussed on Fourier transform IR and Raman microscopy, UV–Vis and near-IR absorption, reflectance and fluorescence methods and other laser-based analytical techniques. Finally, contributions on the use of magnetic resonance spectroscopy, highperformance liquid chromatography and gas chromatography coupled with mass spectrometry, and optical imaging in addition to coherence techniques were also presented. As usual, mobile spectrometry played a major role in the TECHNART conference. Studies of cultural objects often comprise questions on their origin and dating and attribution to artists or workshops. Sometimes stylistic and art-historical examination coupled with information from contemporary technological treatises and secondary literature may be sufficient to answer such questions. However, in many cases the missing information can be deduced from the physical and chemical properties of the artefacts. In its individual materiality, each cultural asset is the result of a wide variety of influences (e.g. production, storage, restoration, preservation). So investigations of physical properties and chemical composition generate important input for answering cultural-historical questions that cannot be solved by historical and philological methods alone. Because of recent technological developments, instrumental diagnostics in art and culture are winning recognition in such fields of transdisciplinary research. Intimately connected with archaeometric investigations are conservation and restoration studies: the development of reversible restoration or conservation concepts requires knowledge of the material compositions and ageing phenomena of the artefacts. The growing importance of physical and chemical diagnostics in the field of cultural heritage is reflected in a variety of conferences, workshops and journals. Hence, the dissemination of new developments in analytical technologies is an important prerequisite for further progresses in such a field of transdisciplinary research. All in all, this special issue represents the state of the art, illustrating how different techniques and different methods can be successfully applied to analytical investigations in the field of cultural heritage. I would like to thank all authors for submitting convincing and newsworthy contributions, all referees for constructive and conducive comments, and finally the central editorial office and the editors for their friendly cooperation.

Cover Picture: Phys. Status Solidi C 6/10

AbstractOn p. 2190 of this issue, Jesús A. Blanco et al. report having succeeded in the synthesis and characterization of γ‐titanium phosphate nanotubes incorporating trioctylamine. The cover picture contains transmission electron microscopy images showing several nanotubes. These nanostructured materials present two or more phases, the interlayer distance being controlled by the alkyl chain length and the amount of amine template as is schematized in the upper part of the picture.The first author, Jesús A. Blanco is an assistant professor at the University of Oviedo, Spain, where he teaches solid state physics and has worked for more than 20 years in materials cience using synchrotron radiation and neutron beam techniques. Current scientific interests are in nanostructured materials and their physical‐chemical properties. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

μSR and neutron scattering studies of spin dynamics

Aspects of the complementary roles of muon and neutron beam techniques in the investigation of magnetic systems are presented and discussed, particularly in the context of studies of spin fluctuations and spin glass-like behaviour in itinerant electron antiferromagnets (e.g. YMn 2, β-MnAl) and ferromagnets (e.g. Ni 3Al).

Salivary gland neoplasms.

Treatment and cure of salivary gland neoplasms requires surgical intervention in most cases. For parotid neoplasms, the most common surgical procedure performed is the superficial parotidectomy with facial nerve preservation. Postoperative radiation therapy is indicated in high-grade salivary gland malignancies and malignancies with increased risk of locoregional recurrence. Primary radiation, including neutron beam techniques, may play a role in certain histologic types or nonoperative candidates. Chemotherapy has yet to result in improvements in survival or quality of life in the treatment of salivary gland malignancy. Advances in radiation therapy techniques, including intensity-modulated radiation therapy, provide opportunities for reduced morbidity.

Recent magnetic structure studies by neutron diffraction

A review is presented of several magnetic structure studies performed recently by neutron diffraction methods. These include a study of the low temperature transition in Fe3O4 by Hamilton and experiments by Roth on the magnetic structure ambiguities of the transition element monoxides. Recent studies using polarized neutron beam techniques are described and data presented on the ferromagnetic scattering by iron and nickel.